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Sample records for sea effects obtained

  1. Assessment Of Sea Surface Salinity Obtain From SMOS And Aquarius Satellites Over Indian Ocean

    NASA Astrophysics Data System (ADS)

    Calla, O. P. N.; Dadhich, Harendra Kumar; Singhal, Shruti

    2013-12-01

    In this paper, assessment is done of Sea Surface Salinity (SSS) obtained from both SMOS and Aquarius satellites for couple of months over Indian Ocean (IO). The SSS values of the Southern Indian Ocean (SIO) are being investigated as the North Indian Ocean (NIO) is found much corrupted with the Radio Frequency Interference and even due to large variability of SSS in IO; the study area has been divided into different sub regions. The data of both the satellites at same location and of same processing level that is Level-2 have been procured and evaluated. The resolution factor is also being taken care for both onboard sensors. The resolution of SMOS L2 data products [1] is 15 X 15 Km and for Aquarius there are three different resolutions according to the BEAM's. BEAM 1 has a resolution of 76 X 94 Km, BEAM 2 has 84X120Km and BEAM3 has 96X156Km. The data have been averaged of SMOS [2] in the same way so as to match up with Aquarius resolution. By this paper we want to convince the readers that measuring SSS from space is a practical idea. SSS remote sensing now bears no more scientific perils than other remote sensing techniques did in their formative years. Advancing technology with proper resources has significantly reduced the errors.

  2. Analysis of geophysical well logs obtained in the State 2-14 borehole, Salton Sea geothermal area, California

    USGS Publications Warehouse

    Paillet, Frederick L.; Morin, R.H.

    1988-01-01

    A complete suite of conventional geophysical well logs was obtained in the upper part of a 3220-m-deep borehole drilled into geothermally altered alluvial sediments on the southeastern edge of the Salton Sea. Geophysical logs obtained in the State 2-14 borehole indicate that neutron porosity, gamma-gamma, and deep-induction logs provide useful information on lithologic trends with depth. The natural gamma log contains almost continuous, high-frequency fluctuations that obscure lithologic trends and that may be related to recent radioisotope redistribution and departure from radiometric equilibrium. Acoustic transit time logs give unrealistically low in situ compressional velocities ranging from 1.8 to 3.0 km/s, whereas acoustic waveform logs indicate that sediment compressional velocities range from less than 3.0 km/s shallower than 1000 m in depth to almost 5.0 km/s at depths greater than 2000 m. Analyses indicate that most log values lie between two lithologic end points: an electrically conductive claystone with moderate neutron porosity, but no effective porosity, and an electrically nonconductive, fully cemented siltstone that has small but finite porosity. -from Authors

  3. Analysis of sea-surface polarization imagery of Hawaii environs obtained by the space shuttle

    NASA Astrophysics Data System (ADS)

    Sidran, Miriam; Egan, Walter G.

    1992-12-01

    Polarimetric images of the earth have been obtained for the first time by means of the Space Shuttle. These depict the environs of Hawaii in three visible bands of polarized light. A transect drawn on each image, crossing only cloud-free ocean areas, has both positive and negative polarization values along its path. These results are compared with those of several models, and with aircraft measurements of a haze-free, hydrosol-free ocean area, regarded as `air truth.' Based on the models and the air truth, the negative percent polarization values are attributed to haze, even though haze is not visible in a photograph taken from space. This haze obscures the effects of wind-generated surface roughness, and suspended hydrosols, so that they cannot be separately distinguished. The Hansen-Travis radiative transfer model predicts that the haze must have a large optical depth. The air truth shows that in the absence of haze, the wind velocity can be characterized by polarimetric measurements. The effect of hydrosols on polarization is not yet clear.

  4. Representation of the Weddell Sea Anomaly obtained by the Swarm constellation

    NASA Astrophysics Data System (ADS)

    Slominska, E.; Blecki, J. S.; Slominski, J.

    2015-12-01

    Recently it has become apparent that the Weddell Sea Anomaly (WSA) and the mid-latitude nighttime summer anomaly (MSNA) are phenomena, which are governed by similar mechanisms. Key questions relate to the fact how do those anomalies set up or how does spatial and altitudinal structure evolve. In-situ registrations of electron density from the Langmuir probe onboard three Swarm satellites are used to study the spatial and temporal evolution of nighttime plasma density enhancements. The study introduces the normalized density difference index INDD to provide global estimates of the phenomenon. The advantage of the index is, that it provides relative values and can be used for further comparison with external missions and exhisting ionospheric models (like IRI). With proposed index, we find signatures the Weddell Sea Anomaly and mid-latitude nighttime summer anomaly in the ionosphere. The study provides evidence that occurrence of the WSA and MSNA is not limited to the local summer conditions but tends to occur in remaining seasons. Analyzed annual trends and spatial pattern of INDD suggest that observed anomalies evince similarity with the behaviour of the equatorial ionosphere. Multi-instrumental analysis based on the Swarm data provide better insight into the WSA phenomenon and should help to acquire full understanding of responsible processes.

  5. Acoustic Images of Submarine landslide in western Sagami Bay obtained by deep sea AUV “URASHIMA” in Sagami bay

    NASA Astrophysics Data System (ADS)

    Kasaya, Takafumi; Tsukioka, Satoshi; Yamamoto, Fujio; Hyakudome, Tadahiro; Sawa, Takao; Yoshida, Hiroshi; Ishibashi, Shojiro; Tahara, Junichiro; Kinoshita, Masataka; Aoki, Taro

    To collect bathymetric data and bottom material information, multi narrow beam echo sounder and/or side scan sonar are usually used over wide area. The autonomous underwater vehicle (AUV) has the advantage of getting closer to the sea surface as compared with a survey from the vessel. URASHIMA is a 3000 m class AUV, is loaded with multi narrow beam depth sounder, side scan sonar and sub-bottom profiler. Using URASHIMA, side scan sonar images and sub-bottom profiles were collected around off Hatsushima Island where mud flow was generated with some large earthquakes occurrence. We could obtain many enough quality side scan sonar images and sub-bottom profiles. Mosaic image was constructed by obtained side scan sonar images, and shows distinctive surface structure. Some irregular patches are detected around the mudflow area 7km off Hatsushima Island. This structure do not relate to the bathymetry obtained by SeaBat8160 on R/V Natsushima. Therefore, these are interpreted as debris generated with earthquakes. Sub-bottom profiles could detect very clear sedimentary structure.

  6. Orbital and suborbital variability in North Atlantic bottom water temperature obtained from deep-sea ostracod Mg/Ca ratios

    USGS Publications Warehouse

    Cronin, T. M.; Dwyer, G.S.; Baker, P.A.; Rodriguez-Lazaro, J.; DeMartino, D.M.

    2000-01-01

    Magnesium/calcium (Mg/Ca) ratios were measured in the deep-sea ostracod (Crustacea) genus Krithe from Chain core 82-24-4PC from the western mid-Atlantic Ridge (3427 m) in order to estimate ocean circulation and bottom water temperature (BWT) variability over the past 200,000 years. Mg/Ca ratios have been used as a paleothermometer because the ratios are controlled primarily by ambient water temperatures at the time the organism secretes its adult carapace. Over the past two glacial-interglacial cycles, Mg/Ca values oscillated between about 7 mmol/mol and 12 mmol/mol, equivalent to a BWT range of 0 to > 3.5??C. The lowest values were obtained on specimens from glacial marine isotope stages (MISs) 2, 4 and 6; the highest values were obtained from specimens from the early part of the Holocene interglacial (MIS 1), and also from MISs 5 and 7. These trends suggest that BWTs in the North Atlantic Ocean fluctuate over orbital time scales. Suborbital variability in Mg/Ca ratios and BWT was also observed for the past 100,000 years. Ratios rose from ~8 mmol/mol to ~10 mmol/mol (implying a BWT increase of ~1 to 3??C) during 14 Mg/Ca excursions. The highest ratios were found in Krithe dated at approximately 32, 36-38, 43, 48, 73, 85 and 93 ka. Although the age model for the Chain 82-24-4PC and temporal resolution do not allow precise correlation, some of these deep-sea bottom temperature excursions appear to correspond to Heinrich events recorded in other regions of the North Atlantic and perhaps Dansgaard-Oeschger interstadial events recorded in Greenland ice cores. If confirmed, this would support the hypothesis that millennial-scale oscillations of climate in the North Atlantic are capable of affecting global climate via thermohaline circulation changes. (C) 2000 Elsevier Science B.V.

  7. Antioedematogenic effect of marrubiin obtained from Marrubium vulgare.

    PubMed

    Stulzer, Hellen K; Tagliari, Monika P; Zampirolo, Julio A; Cechinel-Filho, Valdir; Schlemper, Valfredo

    2006-12-01

    This paper describes the antioedematogenic profile of marrubiin (1), the main constituent of Marrubium vulgare, a medicinal plant used in folk medicine of several countries to treat different pathologies. Compound (1) was analyzed in a model of microvascular leakage in mice ears. The results show that it exhibits significant and dose-related antioedematogenic effects. The results obtained for ID50 values (mg/kg, i.p.) and maximal inhibition (%) for the different phlogistic agents used were as follows: histamine (HIS, 13.84 mg/kg and 73.7%); (BK, 18.82 mg/kg and 70.0%); carrageenan (CAR, 13.61 mg/kg and 63.0%). The other phlogistic agonists, such as prostaglandin E2 (PGE2), caused inhibition of less than 50%. In addition, (1) (100 mg/kg) significantly inhibited the OVO-induced allergic edema in actively sensitized animals (maximal inhibition 67.6+/-4%). Our results demonstrate that the systemic administration of marrubiin exerts a non-specific inhibitory effect on pro-inflammatory agent-induced microvascular extravasation of Evans blue in mouse ear.

  8. Evaluating the substantive effectiveness of SEA: Towards a better understanding

    SciTech Connect

    Doren, D. van; Driessen, P.P.J.; Schijf, B.; Runhaar, H.A.C.

    2013-01-15

    Evaluating the substantive effectiveness of strategic environmental assessment (SEA) is vital in order to know to what extent the tool fulfills its purposes and produces expected results. However, the studies that have evaluated the substantive effectiveness of SEA produce varying outcomes as regards the tool's contribution to decision-making and have used a variety of approaches to appraise its effectiveness. The aim of this article is to discuss the theoretical concept of SEA substantive effectiveness and to present a new approach that can be applied for evaluation studies. The SEA effectiveness evaluation framework that will be presented is composed of concepts of, and approaches to, SEA effectiveness derived from SEA literature and planning theory. Lessons for evaluation can be learned from planning theory in particular, given its long history of analyzing and understanding how sources of information and decisions affect (subsequent) decision-making. Key concepts of this new approach are 'conformance' and 'performance'. In addition, this article presents a systematic overview of process and context factors that can explain SEA effectiveness, derived from SEA literature. To illustrate the practical value of our framework for the assessment and understanding of substantive effectiveness of SEA, three Dutch SEA case studies are examined. The case studies have confirmed the usefulness of the SEA effectiveness assessment framework. The framework proved helpful in order to describe the cumulative influence of the three SEAs on decision-making and the ultimate plan. - Highlights: Black-Right-Pointing-Pointer A new framework to evaluate the substantive effectiveness of SEA is presented. Black-Right-Pointing-Pointer The framework is based on two key concepts: 'conformance' and 'performance.' Black-Right-Pointing-Pointer The practical applicability of the framework is demonstrated by three Dutch cases. Black-Right-Pointing-Pointer The framework allows for a more

  9. Effect of sea sprays on air-sea momentum exchange at severe wind conditions

    NASA Astrophysics Data System (ADS)

    Troitskaya, Yu.; Ezhova, E.; Semenova, A.; Soustova, I.

    2012-04-01

    Wind-wave interaction at extreme wind speed is of special interest now in connection with the problem of explanation of the sea surface drag saturation at the wind speed exceeding 30 m/s. The idea on saturation (and even reduction) of the coefficient of aerodynamic resistance of the sea surface at hurricane wind speed was first suggested in [1] on the basis of theoretical analysis of sensitivity of maximum wind speed in a hurricane to the ratio of the enthalpy and momentum exchange coefficients. Both field [2-4] and laboratory [5] experiments confirmed that at hurricane wind speed the sea surface drag coefficient is significantly reduced in comparison with the parameterization obtained at moderate to strong wind conditions. Two groups of possible theoretical mechanisms for explanation of the effect of the sea surface drag reduction can be specified. In the first group of models developed in [6,7], the sea surface drag reduction is explained by peculiarities of the air flow over breaking waves. Another approach more appropriate for the conditions of developed sea exploits the effect of sea drops and sprays on the wind-wave momentum exchange. Papers[8,9] focused on the effect of the sea drops on stratification of the air-sea boundary layer similar to the model of turbulent boundary layer with the suspended particles [10], while papers [11-13] estimated the momentum exchange of sea drops and air-flow. A mandatory element of the spray induced momentum flux is a parameterization of the momentum exchange between droplets and air flow, which determines the "source function" in the momentum balance equation. In this paper a model describing the motion of a spume droplet, the wind tear away from the crest of a steep surface wave, and then falling into the water. We consider two models for the injection of droplets into the air flow. The first one assumes that the drop starts from the surface at the orbital velocity of the wave. In the second model we consider droplets from

  10. Effects of Mackenzie River Discharge and Bathymetry on Sea Ice in the Beaufort Sea

    NASA Technical Reports Server (NTRS)

    Nghiem, S. V.; Hall, D. K.; Rigor, I. G; Li, P.; Neumann, G.

    2014-01-01

    Mackenzie River discharge and bathymetry effects on sea ice in the Beaufort Sea are examined in 2012 when Arctic sea ice extent hit a record low. Satellite-derived sea surface temperature revealed warmer waters closer to river mouths. By 5 July 2012, Mackenzie warm waters occupied most of an open water area about 316,000 sq km. Surface temperature in a common open water area increased by 6.5 C between 14 June and 5 July 2012, before and after the river waters broke through a recurrent landfast ice barrier formed over the shallow seafloor offshore the Mackenzie Delta. In 2012, melting by warm river waters was especially effective when the strong Beaufort Gyre fragmented sea ice into unconsolidated floes. The Mackenzie and other large rivers can transport an enormous amount of heat across immense continental watersheds into the Arctic Ocean, constituting a stark contrast to the Antarctic that has no such rivers to affect sea ice.

  11. Accentuate the Negative: Obtaining Effective Reviews through Focused Questions.

    ERIC Educational Resources Information Center

    Hart, Geoff

    1997-01-01

    Proposes an approach that emphasizes negative, "what did we do wrong?" questions so that technical communicators can obtain useful feedback on documents. Notes that this approach focuses limited resources on areas that need improvement, rather than areas that already work well and that do not require immediate improvement. (RS)

  12. Antiallergic effect of flavonoid glycosides obtained from Mentha piperita L.

    PubMed

    Inoue, Toshio; Sugimoto, Yukio; Masuda, Hideki; Kamei, Chiaki

    2002-02-01

    Six flavonoid glycosides, eriocitrin (1), narirutin (2), hesperidin (3), luteolin-7-O-rutinoside (4), isorhoifolin (5), diosmin (6), rosmarinic acid (7) and 5,7-dihydroxycromone-7-O-rutinoside (8), were isolated from the aerial part of Mentha piperita L. Among these compounds, compound 4 showed a potent inhibitory effect on histamine release induced by compound 48/80 and antigen-antibody reaction. This compound was more effective than luteolin and luteolin-7-O-glucoside in inhibiting histamine release from rat peritoneal mast cells. Compound 4 also caused a dose-related inhibition of the antigen-induced nasal response and significant effects were observed at doses of 100 and 300 mg/kg. These results indicate that compound 4 may be clinically useful in alleviating the nasal symptoms of allergic rhinitis. PMID:11853178

  13. Validation of Mean Absolute Sea Level of the North Atlantic obtained from Drifter, Altimetry and Wind Data

    NASA Technical Reports Server (NTRS)

    Maximenko, Nikolai A.

    2003-01-01

    Mean absolute sea level reflects the deviation of the Ocean surface from geoid due to the ocean currents and is an important characteristic of the dynamical state of the ocean. Values of its spatial variations (order of 1 m) are generally much smaller than deviations of the geoid shape from ellipsoid (order of 100 m) that makes the derivation of the absolute mean sea level a difficult task for gravity and satellite altimetry observations. Technique used by Niiler et al. for computation of the absolute mean sea level in the Kuroshio Extension was then developed into more general method and applied by Niiler et al. (2003b) to the global Ocean. The method is based on the consideration of balance of horizontal momentum.

  14. A practical method for obtaining useful quantities of pheromones from sea lamprey and other fishes for identification and control

    USGS Publications Warehouse

    Fine, J.M.; Sisler, S.P.; Vrieze, L.A.; Swink, W.D.; Sorensen, P.W.

    2006-01-01

    Pheromonally-mediated trapping is currently being developed for use in sea lamprey control in the Laurentian Great Lakes. To identify and test lamprey pheromones a practical procedure was needed to isolate relatively large quantities of pheromone from lamprey holding water. The present study developed such a technique. It employs Amberlite XAD7HP, an adsorbent resin which we found can extract over 80% of the sea lamprey migratory pheromone from larval holding water at low cost and with relative ease. This technique allowed its to collect tens of milligrams of all three components of the sea lamprey migratory pheromone, eventually permitting both identification and successful field testing. This technique might also be used to collect pheromones released by other species of fish.

  15. Nail surgery: best way to obtain effective anesthesia.

    PubMed

    Jellinek, Nathaniel J; Vélez, Nicole F

    2015-04-01

    Nail procedures require an effective and reliable approach to anesthesia of the distal digit. Several techniques have been described in the literature. Herein, the relevant anatomy of the nail unit, pain pathways, anesthetic options, and several injection approaches to achieve complete anesthesia are reviewed. Also considered are the potential pitfalls and complications and their management. Ultimately, the physician's approach must be individualized to the patient, procedure, and setting. PMID:25828716

  16. Mixture toxicity effects of sea louse control agents in Daphnia magna.

    PubMed

    Rose, Stephanie; Altenburger, Rolf; Sturm, Armin

    2016-02-01

    Caligid sea lice are ectoparasites causing major disease problems in industrial salmon farming. Sea louse control currently relies widely on parasiticides. Among non-target species, crustaceans are particularly susceptible to salmon delousing agents. Drug combinations have recently been suggested for sea louse control; however, no information is available on the non-target effects of such mixtures. To obtain first insights into combination effects of salmon parasiticides, acute toxicity tests with the crustacean model species Daphnia magna were conducted. Four compounds, including two organophosphates and two pyrethroids, were tested individually and in all pair-wise combinations at one fixed concentration ratio. For most combinations, observed toxicities were close to predictions assuming concentration additivity. However, deltamethrin and cypermethrin showed greater than predicted combination effects, while the inverse was observed for deltamethrin and malathion. The results demonstrate combination effects of anti-sea louse agents and suggest that predictions based on concentration additivity are in most cases protective.

  17. Mixture toxicity effects of sea louse control agents in Daphnia magna.

    PubMed

    Rose, Stephanie; Altenburger, Rolf; Sturm, Armin

    2016-02-01

    Caligid sea lice are ectoparasites causing major disease problems in industrial salmon farming. Sea louse control currently relies widely on parasiticides. Among non-target species, crustaceans are particularly susceptible to salmon delousing agents. Drug combinations have recently been suggested for sea louse control; however, no information is available on the non-target effects of such mixtures. To obtain first insights into combination effects of salmon parasiticides, acute toxicity tests with the crustacean model species Daphnia magna were conducted. Four compounds, including two organophosphates and two pyrethroids, were tested individually and in all pair-wise combinations at one fixed concentration ratio. For most combinations, observed toxicities were close to predictions assuming concentration additivity. However, deltamethrin and cypermethrin showed greater than predicted combination effects, while the inverse was observed for deltamethrin and malathion. The results demonstrate combination effects of anti-sea louse agents and suggest that predictions based on concentration additivity are in most cases protective. PMID:26401637

  18. Sea ice effects on salinity in northern oceans

    NASA Astrophysics Data System (ADS)

    Gerdes, Rüdiger; Koeberle, Cornelia

    2016-04-01

    Arctic sea ice volume decreases despite decreasing ice export through Fram Strait. This implies considerable chages in the thermodynamic growth of Arctic sea ice. We use a hindcast simulation with AWI's NAOSIM to estimate the spatial and temporal distribution of freezing and melting. An additional tracer allows us to follow the melt water through the Arctic and into the Nordic seas. We compare the effect of thermodynamic sea ice processes on ocean salinity between the decade of the 1990s and the first decade of the 21st century.

  19. An evaluation of deep-sea benthic megafauna length measurements obtained with laser and stereo camera methods

    NASA Astrophysics Data System (ADS)

    Dunlop, Katherine M.; Kuhnz, Linda A.; Ruhl, Henry A.; Huffard, Christine L.; Caress, David W.; Henthorn, Richard G.; Hobson, Brett W.; McGill, Paul; Smith, Kenneth L.

    2015-02-01

    The 25 year time-series collected at Station M, ~4000 m on the Monterey Deep-sea Fan, has substantially improved understanding of the role of the deep-ocean benthic environment in the global carbon cycle. However, the role of deep-ocean benthic megafauna in carbon bioturbation, remineralization and sequestration is relatively unknown. It is important to gather both accurate and precise measurements of megafaunal community abundance, size distribution and biomass to further define their role in deep-sea carbon cycling and possible sequestration. This study describes initial results from a stereo camera system attached to a remotely operated vehicle and analyzed using the EventMeasure photogrammetric measurement software to estimate the density, length and biomass of 10 species of mobile epibenthic megafauna. Stereo length estimates were compared to those from a single video camera system equipped with sizing lasers and analyzed using the Monterey Bay Aquarium Research Institute's Video Annotation and Reference System. Both camera systems and software were capable of high measurement accuracy and precision (<±1 mm measurement error and precision). However, the oblique angle of the single video camera caused the spatial scale of the image perspective to change with distance from the camera, resulting in error when measurements were not parallel or vertical to two horizontal-oriented scaling lasers. Analysis showed that the stereo system recorded longer lengths and higher biomass estimates than the single video camera system for the majority of the 10 megafauna species studied. The stereo image analysis process took substantially longer than the video analysis and the value of the EventMeasure software tool would be improved with developments in analysis automation. The stereo system is less influenced by object orientation and height, and is potentially a useful tool to be mounted on an autonomous underwater vehicle and for measuring deep-sea pelagic animals where

  20. Effect of atmospheric radiance errors in radiometric sea-surface skin temperature measurements.

    PubMed

    Donlon, C J; Nightingale, T J

    2000-05-20

    Errors in measurements of sea-surface skin temperature (SSST) caused by inappropriate measurements of sky radiance are discussed; both model simulations and in situ data obtained in the Atlantic Ocean are used. These errors are typically caused by incorrect radiometer view geometry (pointing), temporal mismatches between the sea surface and atmospheric views, and the effect of wind on the sea surface. For clear-sky, overcast, or high-humidity atmospheric conditions, SSST is relatively insensitive (<0.1 K) to sky-pointing errors of ?10 degrees and to temporal mismatches between the sea and sky views. In mixed-cloud conditions, SSST errors greater than ?0.25 K are possible as a result either of poor radiometer pointing or of a temporal mismatch between the sea and sky views. Sea-surface emissivity also changes with sea view pointing angle. Sea view pointing errors should remain below 5 degrees for SSST errors of <0.1 K. We conclude that the clear-sky requirement of satellite infrared SSST observations means that sky-pointing errors are small when one is obtaining in situ SSST validation data at zenith angles of <40 degrees . At zenith angles greater than this, large errors are possible in high-wind-speed conditions. We recommend that high-resolution inclinometer measurements always be used, together with regular alternating sea and sky views, and that the temporal mismatch between sea and sky views be as small as possible. These results have important implications for the development of operational autonomous instruments for determining SSST for the long-term validation of satellite SSST.

  1. Effects of heavy sea quarks at low energies.

    PubMed

    Bruno, Mattia; Finkenrath, Jacob; Knechtli, Francesco; Leder, Björn; Sommer, Rainer

    2015-03-13

    We present a factorization formula for the dependence of light hadron masses and low energy hadronic scales on the mass M of a heavy quark: apart from an overall mass-independent factor Q, ratios such as r_{0}(M)/r_{0}(0) are computable in perturbation theory at large M. The perturbation theory part is stable concerning different loop orders. Our nonperturbative Monte Carlo results obtained in a model calculation, where a doublet of heavy quarks is decoupled, match quantitatively to the perturbative prediction. Upon taking ratios of different hadronic scales at the same mass, the perturbative function drops out and the ratios are given by the decoupled theory up to M^{-2} corrections. We verify-in the continuum limit-that the sea quark effects of quarks with masses around the charm mass are very small in such ratios.

  2. Tidal effects of disconnected hydrocarbon seas on Titan.

    PubMed

    Dermott, S F; Sagan, C

    1995-03-16

    Thermodynamic and photochemical arguments suggest that Titan, the largest satellite of Saturn, has a deep ocean of liquid hydrocarbons. At visible wavelengths, Titan's surface is obscured by a thick stratospheric haze, but radar observations have revealed large regions of high surface reflectivity that are inconsistent with a global hydrocarbon ocean. Titan's surface has also been imaged at infrared wavelengths, and the highest-resolution data (obtained by the Hubble Space Telescope) show clear variations in surface albedo and/or topography. The natural interpretation of these observations is that Titan, like the Earth, has continents and oceans. But Titan's high orbital eccentricity poses a problem for this interpretation, as the effects of oceanic tidal friction would have circularized Titan's orbit for most configurations of oceans and continents. Here we argue that a more realistic topography, in which liquid hydrocarbons are confined to a number of disconnected seas or crater lakes, may satisfy both the dynamical and observational constraints. PMID:7885443

  3. Diurnal Thermal Cycling Effects on Backscatter of Thin Sea Ice

    NASA Technical Reports Server (NTRS)

    Nghiem, S. V.; Kwok, R.; Yueh, S. H.; Gow, A. J.; Perovich, D. K.; Hsu, C. C.; Ding, K. H.; Kong, J. A.; Grenfell, T. C.

    1996-01-01

    To invesigate effects on polarimetric backscatter of sea ice grown under diurnal cycling conditions, we carried out an experiment inJanuary 1994 at the outdoor Geophysical Research Facility in the Cold Regions Research and Engineering Laboratory.

  4. Extracellular macromolecules in sea-ice: Effects on sea-ice structure and their implications

    NASA Astrophysics Data System (ADS)

    Ewert, M.; Bayer-Giraldi, M.

    2012-04-01

    Brine inclusions within sea-ice offer a favorable environment for certain marine microorganisms which live and thrive within the ice. These assemblages are a crucial element in the polar ecosystem. Partly entrained by ice platelets into the ice sheet, microorganisms closely interact with the liquid and solid phases of this porous environment (brine and ice), likely influencing their properties. Extracellular polysaccharide substances (EPS) and antifreeze proteins (AFP) have been identified as major elements with the potential to affect ice structure and processes, due to their capability to interact with ice crystals (selected planes in the case of AFPs) and with water molecules and salt ions present in the brine. EPS present in sea water can be selectively retained in the ice during ice formation, with implications for ice structure. Likewise, EPS and AFP released by sea-ice organisms would have a local effect, altering the microenvironment for the benefit of the organism. Macroscopic and microscopic observations showed effects on ice microstructure and a possible increase in brine fraction within the ice caused by AFPs and EPS, implicating changes in ice porosity and permeability. In the following we describe some of the interactions between sea-ice macromolecules, EPS and AFP, and the sea-ice system. We show their influence in ice structure, and discuss probable implications and consequences for microbial survival, distribution of dissolved material between sea-ice and the water column, and possible effects on the seasonal evolution of the ice. All of these could be relevant to the understanding of biogeochemical processes and the limits of habitability, as well as suggest possible applications of these substances.

  5. The effects of large beach debris on nesting sea turtles

    USGS Publications Warehouse

    Fujisaki, Ikuko; Lamont, Margaret M.

    2016-01-01

    A field experiment was conducted to understand the effects of large beach debris on sea turtle nesting behavior as well as the effectiveness of large debris removal for habitat restoration. Large natural and anthropogenic debris were removed from one of three sections of a sea turtle nesting beach and distributions of nests and false crawls (non-nesting crawls) in pre- (2011–2012) and post- (2013–2014) removal years in the three sections were compared. The number of nests increased 200% and the number of false crawls increased 55% in the experimental section, whereas a corresponding increase in number of nests and false crawls was not observed in the other two sections where debris removal was not conducted. The proportion of nest and false crawl abundance in all three beach sections was significantly different between pre- and post-removal years. The nesting success, the percent of successful nests in total nesting attempts (number of nests + false crawls), also increased from 24% to 38%; however the magnitude of the increase was comparably small because both the number of nests and false crawls increased, and thus the proportion of the nesting success in the experimental beach in pre- and post-removal years was not significantly different. The substantial increase in sea turtle nesting activities after the removal of large debris indicates that large debris may have an adverse impact on sea turtle nesting behavior. Removal of large debris could be an effective restoration strategy to improve sea turtle nesting.

  6. Spring-neap tidal effects on satellite ocean color observations in the Bohai Sea, Yellow Sea, and East China Sea

    NASA Astrophysics Data System (ADS)

    Shi, Wei; Wang, Menghua; Jiang, Lide

    2011-12-01

    Eight-year ocean color observations between 2002 and 2009 from the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard the Aqua satellite are used to quantitatively assess the spring-neap tidal effects on variability of ocean optical and biogeochemical properties in the Bohai Sea, Yellow Sea, and East China Sea. We demonstrate that spring-neap tidal variation is one of important ocean processes that drive both the synoptic-scale and mesoscale changes of the ocean optical, biological, and biogeochemical properties in the coastal region. Normalized water-leaving radiance spectra (nLw(λ)), water diffuse attenuation coefficient at the wavelength of 490 nm (Kd(490)), and total suspended matter (TSM) concentration show significant spring-neap variations in the coastal region within a lunar cycle of 29.53 days. In the open ocean, however, spring-neap tidal effects on ocean color data are negligible. The entire areal coverage of the turbid waters (Kd(490) > 0.3 m-1) showing significant spring-neap tidal variations is ˜4-5 × 105 km2. Similar coverage of moderately turbid waters (0.1 < Kd(490) ≤ 0.3 m-1) is also impacted by the spring-neap tides. The magnitude of the spring-neap tidal effects on the variations of the satellite ocean color properties, e.g., Kd(490) and TSM, is in the same order as the seasonal variations in the coastal region. Highest Kd(490) and largest turbid water coverage lag the new moon (or full moon) about 2-3 days, while the lowest Kd(490) and smallest turbid water coverage are also ˜2-3 days behind the one-quarter (or three-quarter) moon. This is attributed to the seawater inertia and the friction against the seabed as well as the sediment resuspension process.

  7. Late Pleistocene variations in Antarctica sea ice. I - Effect of orbital isolation changes. II - Effect of interhemispheric deep-ocean heat exchange

    NASA Technical Reports Server (NTRS)

    Crowley, Thomas J.; Parkinson, Claire L.

    1988-01-01

    A dynamic-thermodynamic sea-ice model is presently used to ascertain the effects of orbitally-induced insolation changes on Antarctic sea-ice cover; the results thus obtained are compared with modified CLIMAP reconstructions of sea-ice 18,000 years ago. The minor influence exerted by insolation on Pleistocene sea-ice distributions is attributable to a number of factors. In the second part of this investigation, variations in the production of warm North Atlantic Deep Water are proposed as a mechanism constituting the linkage between climate fluctuations in the Northern and Southern hemispheres during the Pleistocene; this hypothesis is tested by examining the sensitivity of the dynamic-thermodynamic model for Antarctic sea-ice changes in vertical ocean heat flux, and comparing the simulations with modified CLIMAP sea-ice maps for 18,000 years ago.

  8. The Effect of Ocean Currents on Sea Surface Temperature Anomalies

    NASA Technical Reports Server (NTRS)

    Stammer, Detlef; Leeuwenburgh, Olwijn

    2000-01-01

    We investigate regional and global-scale correlations between observed anomalies in sea surface temperature and height. A strong agreement between the two fields is found over a broad range of latitudes for different ocean basins. Both time-longitude plots and wavenumber-frequency spectra suggest an advective forcing of SST anomalies by a first-mode baroclinic wave field on spatial scales down to 400 km and time scales as short as 1 month. Even though the magnitude of the mean background temperature gradient is determining for the effectiveness of the forcing, there is no obvious seasonality that can be detected in the amplitudes of SST anomalies. Instead, individual wave signatures in the SST can in some cases be followed over periods of two years. The phase relationship between SST and SSH anomalies is dependent upon frequency and wavenumber and displays a clear decrease of the phase lag toward higher latitudes where the two fields come into phase at low frequencies. Estimates of the damping coefficient are larger than generally obtained for a purely atmospheric feedback. From a global frequency spectrum a damping time scale of 2-3 month was found. Regionally results are very variable and range from 1 month near strong currents to 10 month at low latitudes and in the sub-polar North Atlantic. Strong agreement is found between the first global EOF modes of 10 day averaged and spatially smoothed SST and SSH grids. The accompanying time series display low frequency oscillations in both fields.

  9. Leaching behavior of microtektite glass compositions in sea water and the effect of precipitation on glass leaching

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The present study attempts to account for the slow corrosion rates of microtektite glass in nature by comparing the leach rates of synthetic microtektite glass samples in deionized water and in sea-water, respectively. In order to obtain systematic data about leachant composition effects, leach tests were also carried out with synthetic leachant compositions enriched with respect to silica or depleted with respect to certain major components of sea-water (Mg, Ca).

  10. Mesoscale vortices in the Ligurian Sea and their effect on coastal upwelling processes

    NASA Astrophysics Data System (ADS)

    Casella, Elisa; Molcard, Anne; Provenzale, Antonello

    2011-10-01

    We study numerically the dynamics of intense anticyclonic eddies in the Ligurian Sea (NW Mediterranean Sea). To this end, we use the Regional Ocean Modeling System (ROMS) with a resolution of 3 km for a domain covering the whole Ligurian Sea, with an embedded child grid covering the northwestern part of Ligurian Sea at resolution 1 km. The model is forced with daily boundary conditions obtained from the MFS dataset for the year 2006 at the open lateral boundaries. Surface heat and evapotranspiration fluxes are provided by the monthly climatological dataset COADS at 1/2° spatial resolution. For wind forcing, we consider two configurations. In the first setting, the model is forced by the COADS climatological monthly mean wind stresses; in a second configuration, the model is forced by the daily mean wind stresses provided by a mesoscale meteorological model for the area of interest in the year 2006. The latter setting shows the formation of intense anticyclonic eddy structures in the coastal area, generated by the variable winds and by the interaction of transient currents with bottom and coastal topography (in the NW part of the Ligurian Sea). Comparison of model output with satellite SST data shows definite agreement between numerical results and observations. Analysis of the simulation results over the whole year 2006 and of SST satellite images in 2006 and 2007 indicates that coastal anticyclonic eddies are of common occurrence in the Ligurian Sea, with several events per year, mainly concentrated in autumn and winter. The eddies are characterized by a complex pattern of intense vertical velocities and induce strong, long-lasting coastal upwelling events. For this reason, anticyclonic vortices in the coastal area can generate bursts of nutrient input in the euphotic layer and contribute to the fertilization of the Ligurian Sea, with potentially important effects on the dynamics of phyto- and zooplankton.

  11. Microgravity effects of sea urchin fertilization and development

    NASA Technical Reports Server (NTRS)

    Steffen, S.; Simerly, C.; Schatten, H.; Schatten, G.; Fiser, R.

    1992-01-01

    Gravity has been a pervasive influence on all living systems and there is convincing evidence to suggest that it alters fertilization and embryogenesis in several developmental systems. Notwithstanding the global importance of gravity on development, it has only been recently possible to begin to design experiments which might directly investigate the specific effects of this vector. The goal of this research program is to explore and understand the effects of gravity on fertilization and early development using sea urchins as a model system. Sea urchin development has several advantages for this project including the feasibility of maintaining and manipulating these cells during spaceflight, the high percentage of normal fertilization and early development, and the abundant knowledge about molecular, biochemical, and cellular events during embryogenesis which permits detailed insights into the mechanism by which gravity might interfere with development. Furthermore, skeletal calcium is deposited into the embryonic spicules within a day of fertilization permitting studies of the effects of gravity on bone calcium deposition.

  12. High Element Interactivity Information during Problem Solving May Lead to Failure to Obtain the Testing Effect

    ERIC Educational Resources Information Center

    Leahy, Wayne; Hanham, José; Sweller, John

    2015-01-01

    The testing effect occurs when learners who are tested rather than relearning material perform better on a final test than those who relearn. Based on cognitive load theory, it was predicted that the testing effect may not be obtained when the material being learned is high in element interactivity. Three experiments investigated conditions of the…

  13. Effects of shear elasticity on sea bed scattering: numerical examples.

    PubMed

    Ivakin, A N; Jackson, D R

    1998-01-01

    It is known that marine sediments can support both compressional and shear waves. However, published work on scattering from irregular elastic media has not examined the influence of shear on sea bed scattering in detail. A perturbation model previously developed by the authors for joint roughness-volume scattering is used to study the effects of elasticity for three sea bed types: sedimentary rock, sand with high shear speed, and sand with "normal" shear wave speed. Both bistatic and monostatic cases are considered. For sedimentary rock it is found that shear elasticity tends to increase the importance of volume scattering and decrease the importance of roughness scattering relative to the fluid case. Shear effects are shown to be small for sands.

  14. Immunomodulatory effects upon in vitro exposure of California sea lion and southern sea otter peripheral blood leukocytes to domoic acid.

    PubMed

    Levin, Milton; Joshi, Dhanashree; Draghi, Andrew; Gulland, Frances M; Jessup, David; De Guise, Sylvain

    2010-04-01

    During red tide bloom events, the marine diatom Pseudo-nitzschia produces the toxin domoic acid (DA), which has been associated with stranding and mortality events involving California sea lions (Zalophus californianus) and southern sea otters (Enhydra lutris). In addition to these well-documented DA-induced neurotoxic events, there is increasing concern that DA may exert chronic effects, such as immunomodulation, which may potentially increase an individual's susceptibility to a number of opportunistic infections following nonlethal exposure. We investigated the effects of DA on innate (phagocytosis and respiratory burst) and adaptive (mitogen-induced lymphocyte proliferation) immune functions with the use of peripheral blood leukocytes collected from healthy California sea lions and southern sea otters upon in vitro exposure to 0 (unexposed control), 0.0001, 0.001, 0.01, 0.1, 1.0, 10, and 100 microM DA. Domoic acid did not significantly modulate phagocytosis or respiratory burst in either species. For California sea lions, DA significantly increased ConA-induced T-lymphocyte proliferation upon exposure to DA concentrations ranging from 0.0001 to 10 microM, resulting in a nonlinear dose-response curve. There was no effect on lymphocyte proliferation at the highest concentration of DA tested. No effects on lymphocyte proliferation were observed in southern sea otters. Importantly, the in vitro DA concentrations affecting T-cell proliferation were within or below the range of DA in serum measured in free-ranging California sea lions following natural exposure, suggesting a risk for immunomodulation in free-ranging animals. Understanding the risk for immunomodulation upon DA exposure will contribute in the health assessment and management of California sea lions and southern sea otters, as well as guide veterinarians and wildlife rehabilitators in caring for and treating afflicted animals. PMID:20688647

  15. Surfactant-Associated Bacteria in the Sea Surface Microlayer and their Effect on Remote Sensing Technology

    NASA Astrophysics Data System (ADS)

    Kurata, N.; Vella, K.; Tartar, A.; Matt, S.; Shivji, M.; Perrie, W. A.; Soloviev, A.

    2012-12-01

    Synthetic aperture radar remote sensing captures various fine-scale features on the ocean surface such as coastal discharges, oil pollution, vessel traffic, algal blooms and sea slicks. Although numerous factors potentially affect the synthetic aperture radar imaging process, the influence of biogenic and anthropogenic surfactants has been suggested as one of the primary parameters, especially under relatively low wind conditions. Surfactants have a tendency to dampen the short gravity-capillary ocean waves causing the sea surface to smoothen, thus allowing the radar to detect areas of surfactants. Surfactants are found in sea slicks, which are the accumulation of organic material shaped as elongated bands on the ocean's surface. Sea slicks are often observable with the naked eye due to their glassy appearance and can also be seen on synthetic aperture radar images as dark scars. While the sources of surfactants can vary, some are known to be of marine bacteria origin. Countless numbers of marine bacteria are present in the oceanic environment, and their biogeochemical contributions cannot be overlooked. Not only does marine-bacteria produce surfactants, but they also play an important role in the transformation of surfactants. In this study, we profiled the surfactant-associated bacteria composition within the biogenic thin layer of the ocean surface more commonly referred as the sea surface microlayer. Bacterial samples were collected from the sea surface microlayer for comparative analysis from both within and outside of sea slick areas as well as the underlying subsurface water. The bacterial microlayer sampling coincided with synthetic aperture radar satellite, RADARSAT-2, overpasses to demonstrate the simultaneous in-situ measurements during a satellite image capture. The sea surface microlayer sampling method was designed to enable aseptic bacterial sampling. A 47 mm polycarbonate membrane was utilized at each sampling site to obtain a snapshot of the

  16. Observational Evidence of a Hemispheric-wide Ice-ocean Albedo Feedback Effect on Antarctic Sea-ice Decay

    NASA Technical Reports Server (NTRS)

    Nihashi, Sohey; Cavalieri, Donald J.

    2007-01-01

    The effect of ice-ocean albedo feedback (a kind of ice-albedo feedback) on sea-ice decay is demonstrated over the Antarctic sea-ice zone from an analysis of satellite-derived hemispheric sea ice concentration and European Centre for Medium-Range Weather Forecasts (ERA-40) atmospheric data for the period 1979-2001. Sea ice concentration in December (time of most active melt) correlates better with the meridional component of the wind-forced ice drift (MID) in November (beginning of the melt season) than the MID in December. This 1 month lagged correlation is observed in most of the Antarctic sea-ice covered ocean. Daily time series of ice , concentration show that the ice concentration anomaly increases toward the time of maximum sea-ice melt. These findings can be explained by the following positive feedback effect: once ice concentration decreases (increases) at the beginning of the melt season, solar heating of the upper ocean through the increased (decreased) open water fraction is enhanced (reduced), leading to (suppressing) a further decrease in ice concentration by the oceanic heat. Results obtained fi-om a simple ice-ocean coupled model also support our interpretation of the observational results. This positive feedback mechanism explains in part the large interannual variability of the sea-ice cover in summer.

  17. Plankton effect on cod recruitment in the North Sea.

    PubMed

    Beaugrand, Grégory; Brander, Keith M; Alistair Lindley, J; Souissi, Sami; Reid, Philip C

    2003-12-11

    The Atlantic cod (Gadus morhua L.) has been overexploited in the North Sea since the late 1960s and great concern has been expressed about the decline in cod biomass and recruitment. Here we show that, in addition to the effects of overfishing, fluctuations in plankton have resulted in long-term changes in cod recruitment in the North Sea (bottom-up control). Survival of larval cod is shown to depend on three key biological parameters of their prey: the mean size of prey, seasonal timing and abundance. We suggest a mechanism, involving the match/mismatch hypothesis, by which variability in temperature affects larval cod survival and conclude that rising temperature since the mid-1980s has modified the plankton ecosystem in a way that reduces the survival of young cod.

  18. Distribution of Mg and Li in Deep-Sea Scleractinian Corals: Implications for "Vital Effects" and Deep-Sea Thermometry

    NASA Astrophysics Data System (ADS)

    Case, D. H.; Robinson, L. F.; Auro, M. E.; Gagnon, A. C.

    2009-12-01

    The deep ocean is an important component of the climate system, but high resolution records of its behavior are difficult to obtain. Deep-sea corals that form carbonate skeletons have the potential to provide decadal resolution records of the deep ocean. Unfortunately, paleoceanographic approaches to reconstructing temperature in other marine carbonates, including Mg/Ca and ∂18O, are inconsistent with inorganic predictions due to biological mediation, or so called “vital effects." Inspired by a strong Mg/Li to temperature correlation observed in aragonitic and calcitic foraminifera, this study investigated Mg/Li ratios in deep-sea corals as a possible paleothermometer. Two approaches were applied: laser ablation and solution inductively coupled plasma mass spectrometry. For solution analyses Mg/Li was measured to an uncertainty of ~1%, and for laser analyses this uncertainty increased to ~5%. In situ laser analyses across septae and thecae show that Li fractionates similarly to Mg in deep-sea corals relative to Ca, such that the Li/Ca vs. Mg/Ca ratio within a single coral lies on a line with a slope of 3.9 for Balanophyllia and 2.8 for D. dianthus. For D. dianthus, Mg/Ca varies by a factor of nearly three across coral density bands, with high Mg at centers of calcification. Mg/Li varies by only 1.6 times across the same regions. Biomineralization models including a Rayleigh model and a simple open system model are invoked in an attempt to explain these behaviors. As a test of Mg/Li temperature sensitivity twenty-one scleractinian corals, representing five species with a temperature range of 1.8 to 17°C were thoroughly cleaned before dissolution and analysis. Mg/Li correlates to temperature in these corals with R2 values of 0.47 and 0.99 obtained for D. dianthus and Caryophyllia respectively, a significant improvement compared to Mg/Ca. This finding is promising for use of Mg/Li in paleoclimate reconstructions, but further work is required to understand the

  19. Antarctic snow and sea ice processes: Effects on passive microwave emissions and AMSR-E sea ice products

    NASA Astrophysics Data System (ADS)

    Lewis, Michael John, Jr.

    In this research, passive microwave remote sensing products generated for the Antarctic sea ice zone from the Advance Microwave Scanning Radiometer-Earth Observing System (AMSR-E) sensor were compared with various in situ field measurements, both from previous Antarctic campaigns in the published literature and as obtained during the Sea Ice Mass Balance in the Antarctic (SIMBA) project during the International Polar Year (IPY) 2007--2008. Data gathered during the SIMBA project was used to understand the geophysical processes occurring in the sea ice and snow cover of the Bellingshausen Sea and to provide a physical basis for modeling of microwave emissions. In Chapter 2, the AMSR-E sea ice temperature product was compared with AMSR-E snow depth product and previous in situ field measurements. The comparisons were not intended to provide a strict validation of remote sensing products, but to evaluate the physical context of the remotely sensed data and examine potential trends. From examination of the data, it was found that the AMSR-E sea ice temperature product conflicted with several generally observed sea ice properties. The apparent contradictory behavior of the satellite data product is indicative of radiative temperature behavior related to changes in emissivity within the ice pack. Further comparisons of the AMSR-E sea ice temperature product with in situ temperature data from Ice Mass-balance Buoys (IMB) from two Antarctic field programs showed no correlation. However, apparent response of sea ice temperature product to snow/ice interface flooding events was noted. In Chapter 3, an important sea ice process related to the formation of "gap layers" within Antarctic sea ice was examined and modeled. Gap layers are horizontal voids that develop internally within the sea ice structure, often filled with decaying sea ice, saline slush, and a microbial biological community that thrives on the available nutrients. Gap layers are commonly observed in summer melt

  20. Effects of sea level rise on rugged coasts

    SciTech Connect

    Belknap, D.F. )

    1990-05-01

    Rugged coasts are usually rock framed, with more or less discontinuous unconsolidated sediment supply. Evolution of rugged coasts with respect to rising sea level is locally variable, involving rapid changes in facies over short distances and times. Glaciated and tectonic coasts are common examples. Three aspects of coastal evolution dominate rugged coasts during rising sea level: (1) drowning of resistant rocky shores, (2) bluff erosion in sediments or cliff erosion in less resistant rocks, involving marine abrasion as well as terrestrial processes and control by rock structures, and (3) larger scale structural control creating indentations and salients. The third aspect results in embayed coasts that may evolve as estuarine, fjord, or barrier-backbarrier systems. Of overriding concern for stratigraphic interpretation are paleogeography and sediment sources. The Maine coast and nearshore are classic examples of drowned shoreline, and record the effects of glaciation and rapid relative sea level changes over the past 14,000 yr. Offshore at {minus}60 m is a lowstand shoreline (approximately 10,000 yr B.P.), which ranges from cliff to barrier split( ). The inner shelf has evolved through drowning of shelf valleys and peninsulas, bluff erosion and formation of local transgressive barrier-backbarrier systems. Often short-term steady state equilibrium is established until a threshold is reached followed by rapid reorganization at a new location. This occurs in barrier systems, by overtopping of sills in estuaries, and in variable bluff and cliff erosion sites. Preservation potential is high only in valley axes and at sea level stillstand positions.

  1. [Multiple scattering of visible and infrared light by sea fog over wind driving rough sea surface].

    PubMed

    Sun, Xian-Ming; Wang, Hai-Hua; Lei, Cheng-Xin; Shen, Jin

    2013-08-01

    The present paper is concerned with computing the multiple scattering characteristics of a sea fog-sea surface couple system within this context. The single scattering characteristics of sea fog were studied by Mie theory, and the multiple scattering of sunlight by single sea fog layer was studied by radiative transfer theory. The reflection function of a statistically rough ocean surface was obtained using the standard Kirchhoff formulation, with shadowing effects taken into account. The reflection properties of the combined sea fog and ocean surface were obtained employing the adding method, and the results indicated that the reflected light intensity of sea fog increased with the sea background.

  2. Effective impedance spectra for predicting rough sea effects on atmospheric impulsive sounds.

    PubMed

    Boulanger, Patrice; Attenborough, Keith

    2005-02-01

    Two methods of calculating the effective impedance spectra of acoustically hard, randomly rough, two-dimensional surfaces valid for acoustic wavelengths large compared with the roughness scales have been explored. The first method uses the complex excess attenuation spectrum due to a point source above a rough boundary predicted by a boundary element method (BEM) and solves for effective impedance roots identified by a winding number integral method. The second method is based on an analytical theory in which the contributions from random distributions of surface scatterers are summed to obtain the total scattered field. Effective impedance spectra deduced from measurements of the complex excess attenuation above 2D randomly rough surfaces formed by semicylinders and wedges have been compared to predictions from the two approaches. Although the analytical theory gives relatively poor predictions, BEM-deduced effective impedance spectra agree tolerably well with measured data. Simple polynomials have been found to fit BEM-deduced spectra for surfaces formed by intersecting parabolas corresponding to average roughness heights between 0.25 and 7.5 m and for five incidence angles for each average height. Predicted effects of sea-surface roughness on sonic boom profiles and rise time are comparable to those due to turbulence and molecular relaxation effects. PMID:15759695

  3. Effects of oceanic salinity on body condition in sea snakes.

    PubMed

    Brischoux, François; Rolland, Virginie; Bonnet, Xavier; Caillaud, Matthieu; Shine, Richard

    2012-08-01

    Since the transition from terrestrial to marine environments poses strong osmoregulatory and energetic challenges, temporal and spatial fluctuations in oceanic salinity might influence salt and water balance (and hence, body condition) in marine tetrapods. We assessed the effects of salinity on three species of sea snakes studied by mark-recapture in coral-reef habitats in the Neo-Caledonian Lagoon. These three species include one fully aquatic hydrophiine (Emydocephalus annulatus), one primarily aquatic laticaudine (Laticauda laticaudata), and one frequently terrestrial laticaudine (Laticauda saintgironsi). We explored how oceanic salinity affected the snakes' body condition across various temporal and spatial scales relevant to each species' ecology, using linear mixed models and multimodel inference. Mean annual salinity exerted a consistent and negative effect on the body condition of all three snake species. The most terrestrial taxon (L. saintgironsi) was sensitive to salinity over a short temporal scale, corresponding to the duration of a typical marine foraging trip for this species. In contrast, links between oceanic salinity and body condition in the fully aquatic E. annulatus and the highly aquatic L. laticaudata were strongest at a long-term (annual) scale. The sophisticated salt-excreting systems of sea snakes allow them to exploit marine environments, but do not completely overcome the osmoregulatory challenges posed by oceanic conditions. Future studies could usefully explore such effects in other secondarily marine taxa such as seabirds, turtles, and marine mammals.

  4. The effects of aggressive mitigation on steric sea level rise and sea ice changes

    NASA Astrophysics Data System (ADS)

    Körper, J.; Höschel, I.; Lowe, J. A.; Hewitt, C. D.; Salas y Melia, D.; Roeckner, E.; Huebener, H.; Royer, J.-F.; Dufresne, J.-L.; Pardaens, A.; Giorgetta, M. A.; Sanderson, M. G.; Otterå, O. H.; Tjiputra, J.; Denvil, S.

    2013-02-01

    With an increasing political focus on limiting global warming to less than 2 °C above pre-industrial levels it is vital to understand the consequences of these targets on key parts of the climate system. Here, we focus on changes in sea level and sea ice, comparing twenty-first century projections with increased greenhouse gas concentrations (using the mid-range IPCC A1B emissions scenario) with those under a mitigation scenario with large reductions in emissions (the E1 scenario). At the end of the twenty-first century, the global mean steric sea level rise is reduced by about a third in the mitigation scenario compared with the A1B scenario. Changes in surface air temperature are found to be poorly correlated with steric sea level changes. While the projected decreases in sea ice extent during the first half of the twenty-first century are independent of the season or scenario, especially in the Arctic, the seasonal cycle of sea ice extent is amplified. By the end of the century the Arctic becomes sea ice free in September in the A1B scenario in most models. In the mitigation scenario the ice does not disappear in the majority of models, but is reduced by 42 % of the present September extent. Results for Antarctic sea ice changes reveal large initial biases in the models and a significant correlation between projected changes and the initial extent. This latter result highlights the necessity for further refinements in Antarctic sea ice modelling for more reliable projections of future sea ice.

  5. The effect of applying orthogonal projection technique in short window segments to obtain fetal magnetocardiogram

    PubMed Central

    Sriram, Bhargavi; Wilson, James D.; Govindan, Rathinaswamy B.; Lowery, Curtis L.; Preissl, Hubert

    2015-01-01

    Non-invasive recordings of fetal heart and brain have been possible for almost a decade with the advancement in biomagnetic sensors using the SQUID (Superconducting Quantum Interference Device) technology. Techniques such as orthogonal projection and ICA have been applied to attenuate interference from other biological sources such as maternal heart. Successful application of such techniques among other factors depend on the non-stationary characteristics of the signals. To minimize the effect of non-stationarity due to maternal and/or fetal movement in long duration datasets, we proposed to investigate the minimal time window that is needed to obtain averaging with good SNR to apply the orthogonal projection technique to attenuate maternal magnetocardiogram (MCG) and obtain fetal MCG. The quantifying measure is based on spectral estimation of signals from 151-channel SQUID array system. PMID:24109713

  6. Gravity effects obtained from global hydrology models in comparison with high precision gravimetric time series

    NASA Astrophysics Data System (ADS)

    Wziontek, Hartmut; Wilmes, Herbert; Güntner, Andreas; Creutzfeldt, Benjamin

    2010-05-01

    Water mass changes are a major source of variations in residual gravimetric time series obtained from the combination of observations with superconducting and absolute gravimeters. Changes in the local water storage are the main influence, but global variations contribute to the signal significantly. For three European gravity stations, Bad Homburg, Wettzell and Medicina, different global hydrology models are compared. The influence of topographic effects is discussed and due to the long-term stability of the combined gravity time series, inter-annual signals in model data and gravimetric observations are compared. Two sources of influence are discriminated, i.e., the effect of a local zone with an extent of a few kilometers around the gravimetric station and the global contribution beyond 50km. Considering their coarse resolution and uncertainties, local effects calculated from global hydrological models are compared with the in-situ gravity observations and, for the station Wettzell, with local hydrological monitoring data.

  7. Effect of photogrammetric reading error on slope-frequency distributions. [obtained from Apollo 17 mission

    NASA Technical Reports Server (NTRS)

    Moore, H. J.; Wu, S. C.

    1973-01-01

    The effect of reading error on two hypothetical slope frequency distributions and two slope frequency distributions from actual lunar data in order to ensure that these errors do not cause excessive overestimates of algebraic standard deviations for the slope frequency distributions. The errors introduced are insignificant when the reading error is small and the slope length is large. A method for correcting the errors in slope frequency distributions is presented and applied to 11 distributions obtained from Apollo 15, 16, and 17 panoramic camera photographs and Apollo 16 metric camera photographs.

  8. The effect of global climate change on sea level variations along the Bulgarian Black Sea shore

    SciTech Connect

    Mungov, G.; Vesselinov, V.

    1996-12-31

    Data of long-time sea level records along the Bulgarian Black Sea shore are analyzed from the point of view of the global climate change. The analysis of the extreme levels discovers an increase of their appearance during the last 15 years. Two different periods are studied and the recent increases imply the possibility of changes in the regime of the extreme marine events in the Western Black Sea. The cycles in the mean sea levels and the statistical characteristics of the interannual (seasonal) variations are determined. Trends in the sea level records are studied for three basic periods, according the periods in the annual temperature anomalies of the northern hemisphere: 1924--1943; 1944--1973; 1974--1991. The mean sea level rise has maximum value during the first period and minimum during the last third one. This is explained with the decrease of the water inflow into the sea and some initial disturbances in its water balance due to the global climate change. The influence of the global climate change is studied using multiple regression on global environmental data.

  9. Occupation and industry data obtained from death certificates: the effect and influence of case selection.

    PubMed

    Nelson, D E; Swanson, G M; Schwartz, A G; Brix, K; Fine, L J

    1987-01-01

    This study first examined the accuracy of death certificate diagnoses of 4,954 cases of cancer of the lung, liver, nasopharynx, and pleura/peritoneum, then compared usual occupation and industry based on case selection from the Metropolitan Detroit Cancer Surveillance System (MDCSS), a population-based cancer registry, with cases selected from death certificates for the above types of tumors to examine the effect of misclassification. Accuracy of death certificate cancer diagnoses ranged from 93.4% for lung cancer to 28.6% for malignancies of the pleura/peritoneum. The mix of usual occupation/industry titles obtained from death certificate cases and MDCSS cases was similar for lung cancer but not for malignancies of the pleura/peritoneum (35.7% of cases from the registry v 11.1% from death certificates for the automobile industry, P = .05). The effect of misclassification and utility of usual occupation/industry statements on death certificates is discussed.

  10. Influence on isotope effect calculations of the method of obtaining force constants from vibrational data

    SciTech Connect

    Goodson, D.Z.; Sarpal, S.K.; Bopp, P.; Wolfsberg, M.

    1982-01-01

    Reduced isotopic partition function ratios (s/sub 2//s/sub 1/)f are employed in the calculation of isotope effects on thermodynamic equilibrium constrants. The quadratic force constants of the molecular force field are needed to evaluate (s/sub 2//s/sub 1/)f. Often these force constants are directly deduced from observed fundamentals in vibrational spectra and the (s/sub 2//s/sub 1/)f values so obtained are labeled (ANHARM). In a theroretically more valid procedure that is more difficult, one corrects observed fundamentals for anharmonicity on the basis of observed overtone and combination bands and then deduces force constants from these observed harmonic frequencies. The (s/sub 2//s/sub 1/)f values obtained from these force constants are labeled (HARM). (HARM) values and (ANHARM) values are evaluated and the isotope effects calculated with these values are discussed. It is concluded that the consistent use of (ANHARM) values in such calculations is a valid procedure.

  11. Phytochemical analysis, antioxidant and antibacterial effects of sea buckthorn berries.

    PubMed

    Chaman, Saadia; Syed, Nawazish-I-Husain; Danish, Zeeshan; Khan, Farrakh Zia

    2011-07-01

    Sea buckthorn berries are therapeutically used as folk medicine for a variety of diseases, however, the scientific evidence is hardly available to support their role. This study explored their chemical constituents and their role as antioxidant and antibacterial agents. Three common solvents such as petroleum ether (40° - 60°C), chloroform and methanol were successively used for the extraction of active principles from sea buckthorn berries. Five major fractions (F1-F5) were isolated from the active methanol extract by column and thin layer chromatography. An attempt was made to identify the chemical nature of pooled fractions by available spectral means. Antioxidant potential of methanol extract and its fractions was measured by DPPH, formation of phosphomolybdenum complex and TBA methods. The hole-plate diffussion method was used to find out the antibacterial activity. A very brief structure-activity relationship of the potent antioxidant and antimicrobial compounds is discussed. Methanolic extract and its fractions contain numerous phenolic compounds such as flavonoids, which may be responsible for antioxidant and antibacterial effects. PMID:21715268

  12. Biofilm-like properties of the sea surface and predicted effects on air-sea CO2 exchange

    NASA Astrophysics Data System (ADS)

    Wurl, Oliver; Stolle, Christian; Van Thuoc, Chu; The Thu, Pham; Mari, Xavier

    2016-05-01

    Because the sea surface controls various interactions between the ocean and the atmosphere, it has a profound function for marine biogeochemistry and climate regulation. The sea surface is the gateway for the exchange of climate-relevant gases, heat and particles. Thus, in order to determine how the ocean and the atmosphere interact and respond to environmental changes on a global scale, the characterization and understanding of the sea surface are essential. The uppermost part of the water column is defined as the sea-surface microlayer and experiences strong spatial and temporal dynamics, mainly due to meteorological forcing. Wave-damped areas at the sea surface are caused by the accumulation of surface-active organic material and are defined as slicks. Natural slicks are observed frequently but their biogeochemical properties are poorly understood. In the present study, we found up to 40 times more transparent exopolymer particles (TEP), the foundation of any biofilm, in slicks compared to the underlying bulk water at multiple stations in the North Pacific, South China Sea, and Baltic Sea. We found a significant lower enrichment of TEP (up to 6) in non-slick sea surfaces compared to its underlying bulk water. Moreover, slicks were characterized by a large microbial biomass, another shared feature with conventional biofilms on solid surfaces. Compared to non-slick samples (avg. pairwise similarity of 70%), the community composition of bacteria in slicks was increasingly (avg. pairwise similarity of 45%) different from bulk water communities, indicating that the TEP-matrix creates specific environments for its inhabitants. We, therefore, conclude that slicks can feature biofilm-like properties with the excessive accumulation of particles and microbes. We also assessed the potential distribution and frequency of slick-formation in coastal and oceanic regions, and their effect on air-sea CO2 exchange based on literature data. We estimate that slicks can reduce CO2

  13. 03219A, a new Δ(8,9)-pregnene isolated from Streptomyces sp. SCSIO 03219 obtained from a South China Sea sediment.

    PubMed

    Zhang, Yun; Zhou, Xiao; Huang, Hongbo; Tian, Xinpeng; Song, Yongxiang; Zhang, Si; Ju, Jianhua

    2013-06-01

    03219A (1), a new pregnene steroid possessing a rare Δ(8,9)-double bond in the skeleton, together with the known naphthoquinone antibiotic (+)-cryptosporin (2) have been isolated from the fermentation broth of Streptomyces sp. SCSIO 03219, which was isolated from a marine sediment collected in the South China Sea. The structure of 03219A was elucidated using a combination of NMR, MS and X-ray crystallographic methods.

  14. The Effects of Snow Depth Forcing on Southern Ocean Sea Ice Simulations

    NASA Technical Reports Server (NTRS)

    Powel, Dylan C.; Markus, Thorsten; Stoessel, Achim

    2003-01-01

    The spatial and temporal distribution of snow on sea ice is an important factor for sea ice and climate models. First, it acts as an efficient insulator between the ocean and the atmosphere, and second, snow is a source of fresh water for altering the already weak Southern Ocean stratification. For the Antarctic, where the ice thickness is relatively thin, snow can impact the ice thickness in two ways: a) As mentioned above snow on sea ice reduces the ocean-atmosphere heat flux and thus reduces freezing at the base of the ice flows; b) a heavy snow load can suppress the ice below sea level which causes flooding and, with subsequent freezing, a thickening of the sea ice (snow-to-ice conversion). In this paper, we compare different snow fall paramterizations (incl. the incorporation of satellite-derived snow depth) and study the effect on the sea ice using a sea ice model.

  15. Flow-cytometric determination of genotoxic effects of exposure to petroleum in mink and sea otters

    USGS Publications Warehouse

    Bickham, J.W.; Mazet, J.A.; Blake, J.; Smolen, M.J.; Lou, Y.; Ballachey, B.E.

    1998-01-01

    Three experiments were conducted to investigate the genotoxic effects of crude oil on mink and sea otters, In the first experiment, the effects on mink of chronic exposure to weathered Prudhoe Bay crude oil were studied, Female mink were fed a diet that included weathered crude oil for a period of 3 weeks prior to mating, during pregnancy and until weaning. Kits were exposed through lactation and by diet after weaning until 4 months of age. Kidney and liver tissues of the kits were examined using flow cytometry (FCM) and it was found that the genome size was increased in kidney samples from the experimental group compared to the control group. This effect was probably due to some type of DNA amplification and it could have been inherited from the exposed mothers or have been a somatic response to oil exposure in the pups, No evidence of clastogenic effects, as measured by the coefficient of variation (CV) of the G(1) peak, was found in kidney or liver tissue. In the second experiment, yearling female mink were exposed either by diet or externally to crude oil or bunker C fuel oil. Evidence for clastogenic damage was found in spleen tissue for the exposure groups, but not in kidney tissue. No evidence of increased genome size was observed. In the third experiment, blood was obtained from wild-caught sea otters in Prince William Sound. The sea otters represented two populations: one from western Prince William Sound that was potentially exposed to oil from the Exxon Valdez oil spill and a reference population from eastern Prince William Sound that did not receive oil from the spill. The spill had occurred 1.5 years prior to obtaining the blood samples. Although the mean CVs did not differ between the populations, the exposed population had a significantly higher variance of CV measurements and five out of 15 animals from the exposed population had CVs higher than the 95% confidence limits of the reference population, It is concluded that FCM is a sensitive indicator

  16. Anthocyanin copigmentation and color of wine: The effect of naturally obtained hydroxycinnamic acids as cofactors.

    PubMed

    Bimpilas, Andreas; Panagopoulou, Marilena; Tsimogiannis, Dimitrios; Oreopoulou, Vassiliki

    2016-04-15

    Copigmentation of anthocyanins accounts for over 30% of fresh red wine color, while during storage, the color of polymeric pigments formed between anthocyanins and proanthocyanidins predominates. Rosmarinic acid and natural extracts rich in hydroxycinnamic acids, obtained from aromatic plants (Origanum vulgare and Satureja thymbra), were examined as cofactors to fresh Merlot wine and the effect on anthocyanin copigmentation and wine color was studied during storage for 6months. An increase of the copigmented anthocyanins that enhanced color intensity by 15-50% was observed, confirming the ability of complex hydroxycinnamates to form copigments. The samples with added cofactors retained higher percentages of copigmented anthocyanins and higher color intensity, compared to the control wine, up to 3 months. However, the change in the equilibrium between monomeric and copigmented anthocyanins that was induced by added cofactors, did not affect the rate of polymerization reactions during storage.

  17. Anthocyanin copigmentation and color of wine: The effect of naturally obtained hydroxycinnamic acids as cofactors.

    PubMed

    Bimpilas, Andreas; Panagopoulou, Marilena; Tsimogiannis, Dimitrios; Oreopoulou, Vassiliki

    2016-04-15

    Copigmentation of anthocyanins accounts for over 30% of fresh red wine color, while during storage, the color of polymeric pigments formed between anthocyanins and proanthocyanidins predominates. Rosmarinic acid and natural extracts rich in hydroxycinnamic acids, obtained from aromatic plants (Origanum vulgare and Satureja thymbra), were examined as cofactors to fresh Merlot wine and the effect on anthocyanin copigmentation and wine color was studied during storage for 6months. An increase of the copigmented anthocyanins that enhanced color intensity by 15-50% was observed, confirming the ability of complex hydroxycinnamates to form copigments. The samples with added cofactors retained higher percentages of copigmented anthocyanins and higher color intensity, compared to the control wine, up to 3 months. However, the change in the equilibrium between monomeric and copigmented anthocyanins that was induced by added cofactors, did not affect the rate of polymerization reactions during storage. PMID:26616922

  18. Plasticizing effect of ionic liquid on cellulose acetate obtained by melt processing.

    PubMed

    Bendaoud, Amine; Chalamet, Yvan

    2014-08-01

    Cellulose acetate (CA) plasticized by 1-butyl-3-methylimidazolium chloride (BMIMCl) and with diethylphtalate (DEP) was obtained by melt processing at 150°C. The effect and the interaction of ionic liquid with the cellulose acetate and their influence on structural, thermo-mechanical, rheological and tensile properties of CA materials were investigated. Ionic liquid (BMIMCl) has shown a good plasticization and more efficient destruction of the crystalline structure of cellulose acetate than the DEP plasticized CA. BMIMCl interacts intensively with CA molecules due to the pronounced van der Waals interactions, hydrogen bonding and electrostatic nature of ionic liquid. The tensile test and the low Young's modulus for plasticized CA suggest a strong reduction of the interaction between the CA chains due to the presence of the ionic liquid.

  19. Modeling the Effects of Mortality on Sea Otter Populations

    USGS Publications Warehouse

    Bodkin, James L.; Ballachey, Brenda E.

    2010-01-01

    mortality in all simulations eventually led to low proportions of males, leading to instability in projected populations over time. Our findings identify the critical need to understand underlying rates of change that can be acquired only through frequent monitoring of managed populations. Models could be improved through better understanding of the effects of density and demographic and environmental stochasticity on sea otter vital rates. Although our primary objective was to provide information useful in managing harvests of sea otters, our findings have implications for the conservation and management of sea otter populations subjected to other sources of mortality that can be quantified, such as incidental, accidental, or illegal.

  20. Investigation of rain effects on Aquarius Sea Surface Salinity measurements

    NASA Astrophysics Data System (ADS)

    Santos-Garcia, Andrea; Jacob, María. Marta; Jones, W. Linwood; Asher, William E.; Hejazin, Yazan; Ebrahimi, Hamideh; Rabolli, Monica

    2014-11-01

    The Aquarius/SAC-D mission has been providing Sea Surface Salinity (SSS), globally over the ocean, for almost 3 years. As a member of the AQ/SAC-D Cal/Val team, the Central Florida Remote Sensing Laboratory has analyzed these salinity retrievals in the presence of rain and has noted the strong correlation between the spatial patterns of reduced SSS and the spatial distribution of rainfall. It was determined that this is the result of a cause and effect relationship, as opposed to SSS measurement errors. Hence, it is important to understand these SSS changes due to seawater dilution by rain and the associated near-surface salinity stratification. This paper addresses the effects of rainfall on the Aquarius (AQ) SSS retrieval using a macro-scale Rain Impact Model (RIM) in the region of high convective rain over the Inter-tropical Convergence Zone. This model, based on the superposition of a one-dimension eddy diffusion (turbulent diffusion) model, relates sea surface salinity to depth, rain accumulation and time since rainfall. For aiding in the identification of instantaneous and prior rainfall accumulations, an AQ Rain Accumulation product was developed. This product, based on the NOAA CMORPH rain data set, provides the rainfall history for 24 h prior to the observation time, which is integrated over each AQ SSS measurement cell. In this paper results of the RIM validation are presented by comparing AQ measured and RIM simulated SSS for several months of 2012. Results show the high cross correlation for these comparisons and also with the corresponding SSS anomalies relative to HYCOM.

  1. Fertilization envelope assembly in sea urchin eggs inseminated in Cl- deficient sea water: I. Morphological effects.

    PubMed

    Lynn, J W; Goddard, R L; Glas, P; Green, J D

    1988-10-01

    Elevation and hardening of the fertilization envelope (FE) occur within 15 min following insemination of the sea urchin egg. When chloride ions were replaced in the media with various anion substitutes, including methyl sulfonate, nitrates, bromide, and isethionate, the fertilization envelope failed to harden and collapsed back to the surface of the egg of Lytechinus variegatus, L. pictus, and Strongylocentrotus purpuratus. At the light microscopy level, the collapse of the envelope was accompanied by a decrease in birefringence, compared with controls. When examined with electron microscopy, the FEs of eggs inseminated in reduced Cl- solutions failed to transform from an amorphous layer into the more robust laminar structure observed around eggs incubated in normal sea water. Furthermore, in the case of S. purpuratus, the I-T transformation of the FE did not occur. When transfer of the inseminated eggs from the Cl- -deficient sea water to normal sea water was carried out before 10 min elapsed, the envelope did not collapse, and the birefringence of the envelope was similar to that of controls. Partial envelope collapse was also observed in a dose-dependent manner, varying with the concentration of the Cl- in the sea water solution. The results suggest that lack of Cl- in the media may interfere with proper fertilization envelope assembly. Possible mechanisms, including proper incorporation of the cortical granule exudate into the nascent envelope structure, are discussed. PMID:3229726

  2. Effects of oil pollution on the development of sex cells in sea urchins

    NASA Astrophysics Data System (ADS)

    Vashchenko, M. A.

    1980-03-01

    The sea urchin Strongylocentrotus nudus is highly sensitive to oil pollution. Experiments were performed in winter, spring and summer over periods of 15 to 45 days. Experimental urchins were kept in water with hydrocarbon concentrations of 10 to 30 mg l-1, and control urchins in pure sea water. Thermal stimulation by Evdokimov's method was applied to obtain mature sexual products during winter and spring tests. Summer investigations were conducted at temperatures of 17 to 18 °C. The gonads were studied histologically and morphometrically, and the sexual cells obtained were analyzed at the embryological level. No histological and morphometrical differences were recorded between sexual cells of controls and experimentals. However, marked hydrocarbon effects were observed in the embryonic development of artificially fertilized cells from experimental urchins. Control embryos developed normally. Embryogenesis of artificially fertilized gametes from control females and experimental males, and vice versa, was found to be distinctly abnormal. Many abnormalities were identified at the first cleavage stage, as well as in blastula, gastrula and pluteus. Fertilization of experimental eggs with experimental sperm resulted in serious disturbances of embryos, followed by the development of non-viable larvae. On the whole, embryogenesis of sexual cells from experimental urchins was characterized by prominent delay, asynchronism and presence of abnormal non-viable larvae. Consequently, long-term effects of sublethal hydrocarbon concentrations resulted in the formation of defective sex cells and high larval mortality.

  3. An effective encoding scheme of obtaining radial topology structures in distribution networks.

    PubMed

    Wen, Juan; Tan, Yanghong; Zhang, Jianmin

    2016-01-01

    The structure of a distribution network has great effects on economy, power supply reliability and investment of a power system. To obtain an optimal topology from possible topologies, we need to solve an optimisation problem which aims to find a radial structure satisfying operating constraints. As a basis of solving this optimisation problem, the encoding scheme, is to represent the candidate configurations by a series of codes. Numerical candidate topologies and unfeasible codes would lead low efficiency or premature convergence. This paper presents an effective scheme which can rapidly produce all radial configurations of a distribution network. In order to reduce the computational requirement of solution space, initial network is simplified as a topological graph which reserves loop branches and T-nodes. And a loop-branch chain incidence matrix is derived from analyzing the relationship between any two loops. Then the principles of selecting switches of each variable are designed to determine the ranges of the variables. All radial candidate solutions are available rapidly through applying the theory of combination. The scheme presented minimizes the number of solutions and avoids tedious radial checking procedure in view of avoiding any infeasible solutions. The validity of the proposed scheme is verified by illustrative examples. PMID:27652038

  4. Climate change effects on the Baltic Sea borderland between land and sea.

    PubMed

    Strandmark, Alma; Bring, Arvid; Cousins, Sara A O; Destouni, Georgia; Kautsky, Hans; Kolb, Gundula; de la Torre-Castro, Maricela; Hambäck, Peter A

    2015-01-01

    Coastal habitats are situated on the border between land and sea, and ecosystem structure and functioning is influenced by both marine and terrestrial processes. Despite this, most scientific studies and monitoring are conducted either with a terrestrial or an aquatic focus. To address issues concerning climate change impacts in coastal areas, a cross-ecosystem approach is necessary. Since habitats along the Baltic coastlines vary in hydrology, natural geography, and ecology, climate change projections for Baltic shore ecosystems are bound to be highly speculative. Societal responses to climate change in the Baltic coastal ecosystems should have an ecosystem approach and match the biophysical realities of the Baltic Sea area. Knowledge about ecosystem processes and their responses to a changing climate should be integrated within the decision process, both locally and nationally, in order to increase the awareness of, and to prepare for climate change impacts in coastal areas of the Baltic Sea.

  5. Effects of indole-3-acetic acid on Botrytis cinerea isolates obtained from potted plants.

    PubMed

    Martínez, J A; Valdés, R; Gómez-Bellot, M J; Bañón, S

    2011-01-01

    We study the growth of different isolates of Botrytis cinerea collected from potted plants which were affected by Botrytis blight in southern Spain during recent years. These isolates, which show widely phenotypic differences when grown in vitro, are differentially affected by growth temperature, gibberellic acid applications and paclobutrazol, an efficient plant growth retardant and fungicide at the same time. In this work, we have evaluated the effect of the auxin indole-3-acetic acid (IAA) dose (0, 1, 10, and 100 mg/plate) on the growth of the collection of B. cinerea isolates obtained from the following potted plants: Cyclamen persicum, Hydrangea macrophylla, Lantona camara, and Lonicera japonica. B. cinerea produces indolacetic acid, but so far the precise biosynthetic pathway and some effects on this fungal species are still unclear, although recent studies have revealed an antifungal activity of IAA on several fungi, including B. cinerea isolated from harvested fruits. Mycelial growth curves and growth rates assessed from difference in colony areas during the both linear and deceleration phase, conidiation (measured as time of appearance), conidia length (microm), and sclerotia production (number/plate) were evaluated in the isolates, which were grown at 26 degrees C on Petri dishes containing potato dextrose agar for up to 35 days. Mycelial growth curves fitted a typical kinetic equation of fungi grown on solid media. B. cinerea isolates showed a high degree of variability in their growth kinetics, depending on the isolate and auxin dose. This plant growth substance delayed mycelial growth during the linear phase in an isolate-dependent manner, thus isolates from C. persicum, H. macrophylla and L. camara were more affected by IAA than L. japonica. On the other hand, 100 mg of IAA was the critical dose to significantly reduce the growth rate in all isolates and to promote brown-striped hyphae development, especially in isolate from C. persicum. 10 and 100 mg

  6. Resolution Effects on the Mean Square Displacement as Obtained by the Self-Distribution-Function Procedure

    NASA Astrophysics Data System (ADS)

    Benedetto, A.; Magazù, S.; Migliardo, F.; Mondelli, C.; Gonzalez, M. A.

    2012-02-01

    In the present contribution, a procedure for molecular motion characterization based on the evaluation of the Mean Square Displacement (MSD), through the Self-Distribution Function (SDF), is presented. It is shown how MSD, which represents an important observable for the characterization of dynamical properties, can be decomposed into different partial contributions associated to system dynamical processes within a specific spatial scale. It is also shown how the SDF procedure allows us to evaluate both total MSD and partial MSDs through total and partial SDFs. As a result, total MSD is the weighed sum of partial MSDs in which the weights are obtained by the fitting procedure of measured Elastic Incoherent Neutron Scattering (EINS) intensity. We apply SDF procedure to data collected,by IN13, IN10 and IN4 spectrometers (Institute Laue Langevin), on aqueous mixtures of two homologous disaccharides (sucrose and trehalose) and on dry and hydrated (H2O and D2O) lysozyme with and without disaccharides. It emerges that the hydrogen bond imposed network of the water-trehalose mixture appears to be stronger with respect to that of the water-sucrose mixture. This result can justify the higher bioprotectant effectiveness of trehalose. Furthermore, it emerges that partial MSDs of sucrose and trehalose are equivalent in the low Q domain (0÷1.7) Å-1 whereas they are different in the high Q domain (1.7÷4) Å-1. This suggests that the higher structure sensitivity of sucrose should be related to the small spatial observation windows. Moreover, the role of the instrumental resolution in EINS is considered. The nature of the dynamical transition is highlighted and it is shown that it occurs when the system relaxation time becomes shorter than the instrumental energy time. Finally, the bioprotectants effect on protein dynamics and the amplitude of vibrations in lysozyme are presented.

  7. Bioactive compounds of sea cucumbers and their therapeutic effects

    NASA Astrophysics Data System (ADS)

    Shi, Shujuan; Feng, Wenjing; Hu, Song; Liang, Shixiu; An, Nina; Mao, Yongjun

    2016-05-01

    Sea cucumbers belong to the Class Holothuroidea of marine invertebrates. They are commercially valuable and prized as a food and folk medicine in Asia. Nutritionally, sea cucumbers have an impressive profile of valuable nutrients such as vitamins, minerals and amino acids. A number of unique biological and pharmacological activities/properties, including anticancer, anticoagulant/antithrombotic, antimicrobial, antioxidant, antihyperlipidemic, antihyperglycemic, anti-inflammatory, antihypertension and radioprotective, have been ascribed to various compounds isolated from sea cucumbers. The therapeutic properties and medicinal benefits of sea cucumbers can be linked to the presence of a wide array of bioactives, especially triterpene glycosides, acid mucopolysaccharide, sphingoid bases, glycolipids, fucosylated chondroitin sulfate, polysaccharides, phospholipids, cerebrosides, phosphatidylcholines, and other extracts and hydrolysates. This review highlights the valuable bioactive components as well as the multiple therapeutic properties of sea cucumbers with a view to exploring their potential uses as functional foods and a natural source of new multifunctional drugs.

  8. Electrical conductivity of oxidized-graphenic nanoplatelets obtained from bamboo: effect of the oxygen content.

    PubMed

    Gross, K; Barragán, J J Prías; Sangiao, S; De Teresa, J M; Lajaunie, L; Arenal, R; Calderón, H Ariza; Prieto, P

    2016-09-01

    The large-scale production of graphene and reduced-graphene oxide (rGO) requires low-cost and eco-friendly synthesis methods. We employed a new, simple, cost-effective pyrolytic method to synthetize oxidized-graphenic nanoplatelets (OGNP) using bamboo pyroligneous acid (BPA) as a source. Thorough analyses via high-resolution transmission electron microscopy and electron energy-loss spectroscopy provides a complete structural and chemical description at the local scale of these samples. In particular, we found that at the highest carbonization temperature the OGNP-BPA are mainly in a sp(2) bonding configuration (sp(2) fraction of 87%). To determine the electrical properties of single nanoplatelets, these were contacted by Pt nanowires deposited through focused-ion-beam-induced deposition techniques. Increased conductivity by two orders of magnitude is observed as oxygen content decreases from 17% to 5%, reaching a value of 2.3 × 10(3) S m(-1) at the lowest oxygen content. Temperature-dependent conductivity reveals a semiconductor transport behavior, described by the Mott three-dimensional variable range hopping mechanism. From the localization length, we estimate a band-gap value of 0.22(2) eV for an oxygen content of 5%. This investigation demonstrates the great potential of the OGNP-BPA for technological applications, given that their structural and electrical behavior is similar to the highly reduced rGO sheets obtained by more sophisticated conventional synthesis methods. PMID:27483115

  9. Electrical conductivity of oxidized-graphenic nanoplatelets obtained from bamboo: effect of the oxygen content

    NASA Astrophysics Data System (ADS)

    Gross, K.; Prías Barragán, J. J.; Sangiao, S.; De Teresa, J. M.; Lajaunie, L.; Arenal, R.; Ariza Calderón, H.; Prieto, P.

    2016-09-01

    The large-scale production of graphene and reduced-graphene oxide (rGO) requires low-cost and eco-friendly synthesis methods. We employed a new, simple, cost-effective pyrolytic method to synthetize oxidized-graphenic nanoplatelets (OGNP) using bamboo pyroligneous acid (BPA) as a source. Thorough analyses via high-resolution transmission electron microscopy and electron energy-loss spectroscopy provides a complete structural and chemical description at the local scale of these samples. In particular, we found that at the highest carbonization temperature the OGNP-BPA are mainly in a sp2 bonding configuration (sp2 fraction of 87%). To determine the electrical properties of single nanoplatelets, these were contacted by Pt nanowires deposited through focused-ion-beam-induced deposition techniques. Increased conductivity by two orders of magnitude is observed as oxygen content decreases from 17% to 5%, reaching a value of 2.3 × 103 S m-1 at the lowest oxygen content. Temperature-dependent conductivity reveals a semiconductor transport behavior, described by the Mott three-dimensional variable range hopping mechanism. From the localization length, we estimate a band-gap value of 0.22(2) eV for an oxygen content of 5%. This investigation demonstrates the great potential of the OGNP-BPA for technological applications, given that their structural and electrical behavior is similar to the highly reduced rGO sheets obtained by more sophisticated conventional synthesis methods.

  10. Antimycotic effect of the essential oil of Aloysia triphylla against Candida species obtained from human pathologies.

    PubMed

    Oliva, María de las Mercedes; Carezzano, María Evangelina; Gallucci, Mauro Nicolás; Demo, Mirta Susana

    2011-07-01

    The research of alternative substances to treat infections caused by Candida species is a need. Aromatic plants have the ability to produce secondary metabolites, such as essential oils (EO). The antimicrobial properties of Aloysia triphylla (L'Her.) Britton (cedrón) EO has been previously described. The aims of this work were to determine the antimicrobial activity and the effect on the cell structure of the EO of A. triphylla against Candida sp isolated from human illnesses. The EO was obtained by hydrodistillation of A. triphylla leaves. The minimum inhibitory concentration (MIC) was performed with microdilution method and the minimum fungicidal concentration (MFC) was determined. A. triphylla EO's showed antifungal activity against all yeast: C. albicans, C. dubliniensis, C. glabrata, C. krusei, C. guillermondii, C. parapsilosis and C. tropicalis which were resistant to fluconazol (150 mg/mL). The range of MIC values was from: 35 to 140 microg/mL and the MFC: 1842 to 2300 microg/mL. The time of killing at the MFC against C. albicans (3 x 10(5) UFC/mL) was 140 min. The dates of OD620 and OD260 suggest lysis and loss of absorbing material, respectively. The HROM shows distortion in morphology and shape of the cell, with large vacuoles in the cytoplasm. These studies clearly show that A. triphylla EO is a promising alternative for the treatment of candidiasis. PMID:21834253

  11. Electrical conductivity of oxidized-graphenic nanoplatelets obtained from bamboo: effect of the oxygen content

    NASA Astrophysics Data System (ADS)

    Gross, K.; Prías Barragán, J. J.; Sangiao, S.; De Teresa, J. M.; Lajaunie, L.; Arenal, R.; Ariza Calderón, H.; Prieto, P.

    2016-09-01

    The large-scale production of graphene and reduced-graphene oxide (rGO) requires low-cost and eco-friendly synthesis methods. We employed a new, simple, cost-effective pyrolytic method to synthetize oxidized-graphenic nanoplatelets (OGNP) using bamboo pyroligneous acid (BPA) as a source. Thorough analyses via high-resolution transmission electron microscopy and electron energy-loss spectroscopy provides a complete structural and chemical description at the local scale of these samples. In particular, we found that at the highest carbonization temperature the OGNP-BPA are mainly in a sp2 bonding configuration (sp2 fraction of 87%). To determine the electrical properties of single nanoplatelets, these were contacted by Pt nanowires deposited through focused-ion-beam-induced deposition techniques. Increased conductivity by two orders of magnitude is observed as oxygen content decreases from 17% to 5%, reaching a value of 2.3 × 103 S m‑1 at the lowest oxygen content. Temperature-dependent conductivity reveals a semiconductor transport behavior, described by the Mott three-dimensional variable range hopping mechanism. From the localization length, we estimate a band-gap value of 0.22(2) eV for an oxygen content of 5%. This investigation demonstrates the great potential of the OGNP-BPA for technological applications, given that their structural and electrical behavior is similar to the highly reduced rGO sheets obtained by more sophisticated conventional synthesis methods.

  12. Electrical conductivity of oxidized-graphenic nanoplatelets obtained from bamboo: effect of the oxygen content.

    PubMed

    Gross, K; Barragán, J J Prías; Sangiao, S; De Teresa, J M; Lajaunie, L; Arenal, R; Calderón, H Ariza; Prieto, P

    2016-09-01

    The large-scale production of graphene and reduced-graphene oxide (rGO) requires low-cost and eco-friendly synthesis methods. We employed a new, simple, cost-effective pyrolytic method to synthetize oxidized-graphenic nanoplatelets (OGNP) using bamboo pyroligneous acid (BPA) as a source. Thorough analyses via high-resolution transmission electron microscopy and electron energy-loss spectroscopy provides a complete structural and chemical description at the local scale of these samples. In particular, we found that at the highest carbonization temperature the OGNP-BPA are mainly in a sp(2) bonding configuration (sp(2) fraction of 87%). To determine the electrical properties of single nanoplatelets, these were contacted by Pt nanowires deposited through focused-ion-beam-induced deposition techniques. Increased conductivity by two orders of magnitude is observed as oxygen content decreases from 17% to 5%, reaching a value of 2.3 × 10(3) S m(-1) at the lowest oxygen content. Temperature-dependent conductivity reveals a semiconductor transport behavior, described by the Mott three-dimensional variable range hopping mechanism. From the localization length, we estimate a band-gap value of 0.22(2) eV for an oxygen content of 5%. This investigation demonstrates the great potential of the OGNP-BPA for technological applications, given that their structural and electrical behavior is similar to the highly reduced rGO sheets obtained by more sophisticated conventional synthesis methods.

  13. Antimycotic effect of the essential oil of Aloysia triphylla against Candida species obtained from human pathologies.

    PubMed

    Oliva, María de las Mercedes; Carezzano, María Evangelina; Gallucci, Mauro Nicolás; Demo, Mirta Susana

    2011-07-01

    The research of alternative substances to treat infections caused by Candida species is a need. Aromatic plants have the ability to produce secondary metabolites, such as essential oils (EO). The antimicrobial properties of Aloysia triphylla (L'Her.) Britton (cedrón) EO has been previously described. The aims of this work were to determine the antimicrobial activity and the effect on the cell structure of the EO of A. triphylla against Candida sp isolated from human illnesses. The EO was obtained by hydrodistillation of A. triphylla leaves. The minimum inhibitory concentration (MIC) was performed with microdilution method and the minimum fungicidal concentration (MFC) was determined. A. triphylla EO's showed antifungal activity against all yeast: C. albicans, C. dubliniensis, C. glabrata, C. krusei, C. guillermondii, C. parapsilosis and C. tropicalis which were resistant to fluconazol (150 mg/mL). The range of MIC values was from: 35 to 140 microg/mL and the MFC: 1842 to 2300 microg/mL. The time of killing at the MFC against C. albicans (3 x 10(5) UFC/mL) was 140 min. The dates of OD620 and OD260 suggest lysis and loss of absorbing material, respectively. The HROM shows distortion in morphology and shape of the cell, with large vacuoles in the cytoplasm. These studies clearly show that A. triphylla EO is a promising alternative for the treatment of candidiasis.

  14. High tides and rising seas: potential effects on estuarine waterbirds

    USGS Publications Warehouse

    Erwin, R.M.; Sanders, G.M.; Prosser, D.J.; Cahoon, D.R.; Greenberg, Russell; Maldonado, Jesus; Droege, Sam; McDonald, M.V.

    2006-01-01

    Coastal waterbirds are vulnerable to water-level changes especially under predictions of accelerating sea-level rise and increased storm frequency in the next century. Tidal and wind-driven fluctuations in water levels affecting marshes, their invertebrate communities, and their dependent waterbirds are manifested in daily, monthly, seasonal, annual, and supra-annual (e.g., decadal or 18.6-yr) periodicities. Superimposed on these cyclic patterns is a long-term (50?80 yr) increase in relative sea-level rise that varies from about 2?4 + mm/yr along the Atlantic coastline. At five study sites selected on marsh islands from Cape Cod, Massachusetts to coastal Virginia, we monitored marsh elevation changes and flooding, tide variations over time, and waterbird use. We found from longterm marsh core data that marsh elevations at three of five sites may not be sufficient to maintain pace with current sea-level rise. Results of the short-term (3?4 yr) measures using surface elevation tables suggest a more dramatic difference, with marsh elevation change at four of five sites falling below relative sea-level rise. In addition, we have found a significant increase (in three of four cases) in the rate of surface marsh flooding in New Jersey and Virginia over the past 70?80 yr during May?July when waterbirds are nesting on or near the marsh surface. Short-term, immediate effects of flooding will jeopardize annual fecundity of many species of concern to federal and state agencies, most notably American Black Duck (Anas rubripes), Nelson?s Sharp-tailed Sparrow (Ammodramus nelsoni), Saltmarsh Sharp-tailed Sparrow (A. caudacutus), Seaside Sparrow (A. maritima), Coastal Plain Swamp Sparrow (Melospiza georgiana nigrescens), Black Rail (Laterallus jamaicensis), Forster?s Tern (Sterna forsteri), Gull-billed Tern (S. nilotica), Black Skimmer (Rynchops niger), and American Oystercatcher (Haemotopus palliatus). Forster?s Terns are probably most at risk given the large proportion of their

  15. Effect of diets supplemented with different sources of astaxanthin on the gonad of the sea urchin Anthocidaris crassispina.

    PubMed

    Peng, Juan; Yuan, Jian-Ping; Wang, Jiang-Hai

    2012-08-01

    The effect of the microalgae Haematococcus pluvialis and Chorella zofingiensis, and synthetic astaxanthin on the gonad of the sea urchin Anthocidaris crassispina was studied. The basal diet was supplemented with H. pluvialis, C. zofingiensis, or synthetic astaxanthin, at two levels of astaxanthin (approximately 400 mg/kg and 100 mg/kg), to obtain the experimental diets HP1, HP2, CZ1, CZ2, AST1, and AST2, respectively, for two months of feeding experiment. The results showed that the concentrations of astaxanthin in the gonads of the sea urchins fed these experimental diets ranged from 0.15 to 3.01 mg/kg dry gonad weight. The higher astaxanthin levels (>2.90 mg/kg) were found in the gonads of the sea urchins fed the diets HP1 (containing 380 mg/kg of astaxanthins, mostly mono- and diesters) and AST1 (containing 385 mg/kg of synthetic astaxanthin). The lowest astaxanthin level (0.15 mg/kg) was detected in the gonads of the sea urchins fed the diet CZ2 (containing 98 mg/kg of astaxanthins, mostly diesters). Furthermore, the highest canthaxanthin level (7.48 mg/kg) was found in the gonads of the sea urchins fed the diet CZ1 (containing 387 mg/kg of astaxanthins and 142 mg/kg of canthaxanthin), suggesting that astaxanthins, especially astaxanthin esters, might not be assimilated as easily as canthaxanthin by the sea urchins. Our results show that sea urchins fed diets containing astaxanthin pigments show higher incorporation of these known antioxidant constituents, with the resultant seafood products therefore being of potential higher nutritive value.

  16. Dietary patterns obtained through principal components analysis: the effect of input variable quantification.

    PubMed

    Smith, Andrew D A C; Emmett, Pauline M; Newby, P K; Northstone, Kate

    2013-05-28

    Principal components analysis (PCA) is a popular method for deriving dietary patterns. A number of decisions must be made throughout the analytic process, including how to quantify the input variables of the PCA. The present study aims to compare the effect of using different input variables on the patterns extracted using PCA on 3-d diet diary data collected from 7473 children, aged 10 years, in the Avon Longitudinal Study of Parents and Children. Four options were examined: weight consumed of each food group (g/d), energy-adjusted weight, percentage contribution to energy of each food group and binary intake (consumed/not consumed). Four separate PCA were performed, one for each intake measurement. Three or four dietary patterns were obtained from each analysis, with at least one component that described 'more healthy' and 'less healthy' diets and one component that described a diet with high consumption of meat, potatoes and vegetables. There were no obvious differences between the patterns derived using percentage energy as a measurement and adjusting weight for total energy intake, compared to those derived using gram weights. Using binary input variables yielded a component that loaded positively on reduced fat and reduced sugar foods. The present results suggest that food intakes quantified by gram weights or as binary variables both resulted in meaningful dietary patterns and each method has distinct advantages: weight takes into account the amount of each food consumed and binary intake appears to describe general food preferences, which are potentially easier to modify and useful in public health settings. PMID:22950853

  17. Effect of modified atmosphere packaging (MAP) on quality of Sea Buckthorn during postharvest storage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Modified atmosphere packaging (MAP) has been used to retain the quality of postharvest produce. In the present study the effect of MAP on quality of berry fruit of Sea buckthorn (Hippophae rhamnoides L., a hardy, deciduous shrub, native to Asia) during refrigerated storage was investigated. Sea buck...

  18. Stratospheric Ozone-induced Indirect Radiative Effects on Antarctic Sea Ice

    NASA Astrophysics Data System (ADS)

    Hu, Y.; Xia, Y.; LIU, J.; Huang, Y.

    2015-12-01

    Recent studies demonstrated that the Antarctic Ozone Hole has important influences on Antarctic sea ice. While all these have focused on stratospheric ozone-induced dynamic effects on sea ice, here we show results that ozone-induced indirect radiative effects have important influences on Antarctic sea ice. Our simulations demonstrate that the recovery of the Antarctic Ozone Hole causes equatorward shift of clouds over the Southern Ocean. The cloud-band shift leads to reduction of downward infrared radiation, which causes surface cooling. On the other hand, it also causes increasing solar radiation on the surface. However, the increase in solar radiation is offset by surface reflection due to increasing sea ice. As a result solar radiation absorbed by the surface is reduced, which also causes surface cooling. Therefore, the overall ozone-induced cloud radiative effect is to cool the surface and causes expansion of sea ice around the Antarctic. As shown in previous studies, the cloud-band shift is associated with the equatorward shift of the westerly jet stream around the Antarctic. Our simulations also demonstrate increasing snow rate near the sea ice edge, which also contributes to Antarctic sea-ice expansion. The ozone-induced cloud radiative effect would mitigate Antarctic sea-ice melting due to greenhouse warming in the 21st century.

  19. Pathological effects of cyanobacteria on sea fans in southeast Florida.

    PubMed

    Kiryu, Y; Landsberg, J H; Peters, E C; Tichenor, E; Burleson, C; Perry, N

    2015-07-01

    In early August 2008, observations by divers indicated that sea fans, particularly Gorgonia ventalina, Gorgonia flabellum, and Iciligorgia schrammi, were being covered by benthic filamentous cyanobacteria. From August 2008 through January 2009 and again in April 2009, tissue samples from a targeted G. ventalina colony affected by cyanobacteria and from a nearby, apparently healthy (without cyanobacteria) control colony, were collected monthly for histopathological examination. The primary cellular response of the sea fan to overgrowth by cyanobacteria was an increase in the number of acidophilic amoebocytes (with their granular contents dispersed) that were scattered throughout the coenenchyme tissue. Necrosis of scleroblasts and zooxanthellae and infiltration of degranulated amoebocytes were observed in the sea fan surface tissues at sites overgrown with cyanobacteria. Fungal hyphae in the axial skeleton were qualitatively more prominent in cyanobacteria-affected sea fans than in controls. PMID:25958261

  20. (abstract) A Polarimetric Model for Effects of Brine Infiltrated Snow Cover and Frost Flowers on Sea Ice Backscatter

    NASA Technical Reports Server (NTRS)

    Nghiem, S. V.; Kwok, R.; Yueh, S. H.

    1995-01-01

    A polarimetric scattering model is developed to study effects of snow cover and frost flowers with brine infiltration on thin sea ice. Leads containing thin sea ice in the Artic icepack are important to heat exchange with the atmosphere and salt flux into the upper ocean. Surface characteristics of thin sea ice in leads are dominated by the formation of frost flowers with high salinity. In many cases, the thin sea ice layer is covered by snow, which wicks up brine from sea ice due to capillary force. Snow and frost flowers have a significant impact on polarimetric signatures of thin ice, which needs to be studied for accessing the retrieval of geophysical parameters such as ice thickness. Frost flowers or snow layer is modeled with a heterogeneous mixture consisting of randomly oriented ellipsoids and brine infiltration in an air background. Ice crystals are characterized with three different axial lengths to depict the nonspherical shape. Under the covering multispecies medium, the columinar sea-ice layer is an inhomogeneous anisotropic medium composed of ellipsoidal brine inclusions preferentially oriented in the vertical direction in an ice background. The underlying medium is homogeneous sea water. This configuration is described with layered inhomogeneous media containing multiple species of scatterers. The species are allowed to have different size, shape, and permittivity. The strong permittivity fluctuation theory is extended to account for the multispecies in the derivation of effective permittivities with distributions of scatterer orientations characterized by Eulerian rotation angles. Polarimetric backscattering coefficients are obtained consistently with the same physical description used in the effective permittivity calculation. The mulitspecies model allows the inclusion of high-permittivity species to study effects of brine infiltrated snow cover and frost flowers on thin ice. The results suggest that the frost cover with a rough interface

  1. Effects of Methylphenidate and Morphine on Delay-Discount Functions Obtained within Sessions

    ERIC Educational Resources Information Center

    Pitts, Raymond C.; McKinney, A. Patrick

    2005-01-01

    Four rats responded under a "self-control" procedure designed to obtain delay- discount functions within sessions. Each session consisted of seven blocks, with seven trials within each block. Each block consisted of two initial forced- choice trials followed by five free-choice trials. On choice trials, the rats could press either of two…

  2. Effects of sea state on offshore wind resourcing in Florida

    NASA Astrophysics Data System (ADS)

    Collier, Cristina

    Offshore resource assessment relies on estimating wind speeds at turbine hub height using observations typically made at substantially lower height. The methods used to adjust from observed wind speeds to hub height can impact resource estimation. The importance of directional sea state is examined, both as seasonal averages and as a function of the diurnal cycle. A General Electric 3.6 MW offshore turbine is used as a model for a power production. Including sea state increases or decreases seasonally averaged power production by roughly 1%, which is found to be an economically significant change. These changes occur because the sea state modifies the wind shear (vector wind difference between the buoy height and the moving surface) and therefore the extrapolation from the observation to hub height is affected. These seemingly small differences in capacity can alter profits by millions of dollars depending upon the size of the farm and fluctuations in price per kWh throughout the year. A 2% change in capacity factor can lead to a 10 million dollar difference from total kWh produced from a wind farm of 100 3.6MW turbines. These economic impacts can be a deciding factor in determining whether a resource is viable for development. Modification of power output due to sea states are shown for seasonal and diurnal time scales. Three regions are examined herein: West Florida, East Florida, and Nantucket Sound. The average capacity after sea state is included suggests areas around Florida could provide substantial amounts of wind power throughout three-fourths of the calendar year. At certain times of day winter average produced capacity factors in West Florida can be up to 45% more than in summer when sea state is included. Nantucket Sound capacity factors are calculated for comparison to a region near a planned United States offshore wind farm. This study provides evidence to suggest including sea state in offshore wind resource assessment causes economically significant

  3. The interaction of the sea breezes with the boundary layer along the Red Sea coast and its effect on the dust transport

    NASA Astrophysics Data System (ADS)

    Khan, Basit Ali; Stenchikov, Georgiy; Abualnaja, Yasser

    2013-04-01

    Sea and land breezes are common meteorological phenomena in most coastal regions of the world. The thermally induced mesoscale circulation of sea breezes modifies the planetary boundary layer (PBL) by forming a convective internal boundary layer (CIBL), which can trap dust and other pollutants in the thin convective layer while the return flow can transport dust and pollutants from the land towards the sea. We used the Advanced Research WRF (ARW) modeling system to study the structure and dynamics of sea breezes in the middle region of the Red Sea (around 25°N) on the western coast of Saudi Arabia. Results showed the existence of two thermal circulations on both the western and eastern coasts of the Red Sea. The modeling results are consistent with observations from buoys and meteorological towers along the Saudi Arabian coast and suggest that the onset of the sea breeze in this area typically occurs at about 0800 Local Standard Time (LST). The sea breeze decays after 1700 LST, although the timing of the onset and decay could be affected by the sea-land thermal gradient, topography, the sea-land orientation and the direction and strength of the wind. The depth of the predicted inflow layer reaches one kilometer while the height of sea breeze head may reach three kilometers. The rocky mountain range of Al-Sarawat, along the Saudi coast line, restricts the inland propagation of the sea breeze and significantly affects the structure of the flow. We conducted a detailed process analysis of our simulation results to understand the sea breeze and PBL interaction and its effect on local meteorology and dust transport.

  4. Carbon dioxide, hydrographic, and chemical data obtained during the R/V Meteor Cruise 11/5 in the South Atlantic and Northern Weddell Sea areas (WOCE sections A-12 and A-21)

    SciTech Connect

    Chipman, D.W.; Takahashi, T.; Breger, D.; Sutherland, S.C.; Kozyr, A. |; Gaslightwala, A.F. |

    1994-07-01

    This document presents the procedures and methods used to obtain carbon dioxide (CO{sub 2}), hydrographic, and chemical data during R/V Meteor Expedition 11/5 in the South Atlantic Ocean, including the Drake Passage; the Northern Weddell Sea; and the Eastern South Atlantic Ocean. This cruise was conducted as part of the World Ocean Circulation Experiment (WOCE). The cruise started from Ushuaia, Argentina, on January 23, 1990, and ended at Capetown, South Africa on March 8, 1990. Samples were collected at 78 stations that covered the Drake Passage; the Northern Weddell Sea; a section along the 58 W parallel; and two segmented S-N sections between the Northern Weddell Sea and Capetown, South Africa. Measurements taken at WOCE sections A-12 and A-21 included pressure, temperature, salinity measured by the Conductivity, Temperature and Depth sensor (CTD); bottle salinity; oxygen; phosphate; nitrate; nitrate; silicate; total carbon concentration (TCO{sub 2}); and partial pressure of CO{sub 2} (pCO{sub 2}) measured at 20 C. In addition, potential density at 0 decibar (dbar) and potential temperature were calculated from the measured variables. The TCO{sub 2} concentration in seawater samples was measured using a coulometer with an estimated precision of approximately {+-} {mu}mol/kg.

  5. A comparison of the three methods used to obtain acoustic measurements for the NASA Flight Effects Program

    NASA Technical Reports Server (NTRS)

    Mueller, A. W.

    1980-01-01

    The NASA Flight Effects Program has a requirement to compare acoustic data obtained from flyover, static test stand, and wind tunnel tests. Results a laboratory study of the acoustic characteristics of the three technqiues used to measure noise during these tests are presented. Recommendations are made to allow for a comparison of data obtained with each technique.

  6. Sea salt production over Bay of Bengal : Effect of salinity

    NASA Astrophysics Data System (ADS)

    K, K. N.; S K, S.; S S, B.; K, K.

    2015-12-01

    Marine aerosols constitute one of the most important natural aerosol systems globally and play an important role in global climate regulation and the marine biogenic system. One of the major constituents of the marine aerosol system is sea salt. Sea salt aerosols are produced via the bubble-bursting process resulting from whitecap generation (due to high wind speed). The resulting sea salt particles are of sub micrometre sizes and go up to a few micrometres. An increase in sea salt mass is primarily associated with increasing wind speeds. The increase in wind speed not only increases the mass concentration of the small-sized sea salt particles but also that of higher-sized particles. This behaviour is constrained by other factors like temperature and salinity. In the present work, this variability in the change in mass concentration of sea salt aerosol is studied with respect to the wind speed variation over Bay of Bengal (BoB). This work includes measurements from two field experiments held on 2006 ((ICARB) March-April) and 2012 ((CTCZ) July-August) over BoB. An analysis of the mass concentration with the wind history showed the mass concentration increasing with the increase in wind speed. Here wind history is used instead of instantaneous wind speed, because it is a good indicator of dependence of mass concentrations on wind speed. However, the cruise held in 2012 showed the size of particles constraining to 2.5 μm unlike the cruise in 2006. This difference in the size of the particles formed is majorly due to change in salinity. In 2012, the cruise was during summer monsoon season wherein the high runoff associated with high precipitation lead to reduced salinity. Whereas in 2006, the cruise was in summer season during which high evaporation lead to increase in salinity. This shows that with lower salinity the sea salt particles formed will be of smaller size. This also shows that apart from wind speed, salinity also affects the sea salt production.

  7. Effect of histologic processing on dimensions of skin samples obtained from cat cadavers.

    PubMed

    Jeyakumar, Sakthila; Smith, Annette N; Schleis, Stephanie E; Cattley, Russell C; Tillson, D Michael; Henderson, Ralph A

    2015-11-01

    OBJECTIVE To determine changes in dimensions of feline skin samples as a result of histologic processing and to identify factors that contributed to changes in dimensions of skin samples after sample collection. SAMPLE Cadavers of 12 clinically normal cats. PROCEDURES Skin samples were obtained bilaterally from 3 locations (neck, thorax, and tibia) of each cadaver; half of the thoracic samples included underlying muscle. Length, width, and depth were measured at 5 time points (before excision, after excision, after application of ink to mark tissue margins, after fixation in neutral-buffered 10% formalin for 36 hours, and after completion of histologic processing and staining with H&E stain). Measurements obtained after sample collection were compared with measurements obtained before excision. RESULTS At the final time point, tissue samples had decreased in length (mean decrease, 32.40%) and width (mean decrease, 34.21%) and increased in depth (mean increase, 54.95%). Tissue from the tibia had the most shrinkage in length and width and that from the neck had the least shrinkage. Inclusion of underlying muscle on thoracic skin samples did not affect the degree of change in dimensions. CONCLUSIONS AND CLINICAL RELEVANCE In this study, each step during processing from excision to formalin fixation and histologic processing induced changes in tissue dimensions, which were manifested principally as shrinkage in length and width and increase in depth. Most of the changes occured during histologic processing. Inclusion of muscle did not affect thoracic skin shrinkage. Shrinkage should be a consideration when interpreting surgical margins in clinical cases. 945). PMID:26512538

  8. Feather keratin hydrolysates obtained from microbial keratinases: effect on hair fiber

    PubMed Central

    2013-01-01

    Background Hair is composed mainly of keratin protein and a small amount of lipid. Protein hydrolysates, in particular those with low molecular weight distribution have been known to protect hair against chemical and environmental damage. Many types of protein hydrolysates from plants and animals have been used in hair and personal care such as keratin hydrolysates obtained from nails, horns and wool. Most of these hydrolysates are obtained by chemical hydrolysis and hydrothermal methods, but recently hydrolyzed hair keratin, feather keratin peptides, and feather meal peptides have been obtained by enzymatic hydrolysis using Bacillus spp in submerged fermentation. Results Keratin peptides were obtained by enzymatic hydrolysis of keratinases using Bacillus subtilis AMR. The microorganism was grown on a feather medium, pH 8.0 (1% feathers) and supplemented with 0.01% of yeast extract, for 5 days, at 28°C with agitation. The supernatant containing the hydrolysates was colleted by centrifugation and ultra filtered in an AMICON system using nano–membranes (Millipore – YC05). The Proteins and peptides were analyzed using HPTLC and MALDI-TOF-MS. Commercial preparations of keratin hydrolysates were used as a comparative standard. After five days the feather had been degraded (90-95%) by the peptidases and keratinases of the microorganism. MALDI-TOF mass spectrometry showed multiple peaks that correspond to peptides in the range of 800 to 1079 Daltons and the commercial hydrolysate was in the range of 900 to 1400 Da. HPTLC showed lower molecular mass peptides and amino acids in the enzymatic hydrolysate when compared with the commercial hydrolysate . A mild shampoo and a rinse off conditioner were formulated with the enzymatic hydrolysate and applied to hair fibers to evaluate the hydration, with and without heat, using a Corneometer® CM 825. The hydration was more efficient with heat, suggesting a more complete incorporation of hydrolysates into the fibers

  9. Assessment of the bifidogenic effect of substituted xylo-oligosaccharides obtained from corn straw.

    PubMed

    Moniz, Patrícia; Ho, Ai Ling; Duarte, Luís C; Kolida, Sofia; Rastall, Robert A; Pereira, Helena; Carvalheiro, Florbela

    2016-01-20

    This work evaluates the bifidogenic potential of substituted xylo-oligosaccharides (XOS) obtained from a lignocellulosic feedstock (corn straw). Autohydrolysis was used to selectively hydrolyse the xylan-rich hemicellulosic fraction and the soluble oligosaccharides were purified by gel filtration chromatography. Selected oligosaccharides fractions within the target ranges of polymerization degree (4-6 and 9-21, samples S1 and S2, respectively) were characterized and their bifidogenic potential was investigated by in vitro fermentations using human fecal inocula. Bacterial growth was assessed by fluorescent in situ hybridization (FISH). XOS consumption and short-chain fatty acids (SCFA) production were evaluated and compared with commercial oligosaccharides. Under the tested conditions, all the substrates were utilized by the microbiota, and fermentation resulted in increased bifidobacteria populations. Samples S1 and S2 increased bifidobacteria populations and the production profile of SCFA was similar for XOS samples and commercial oligosaccharides although XOS samples displayed the highest concentration of SCFA on longer fermentation times.

  10. Effect of lyophilization on the stability of gonyautoxins obtained from contaminated mussels.

    PubMed

    Louzao, M C; Alfonso, A; Botana, A M; Goenaga, X; Cabado, A G; Vieytes, M R; Botana, L M

    1994-07-01

    This study describes the stability of gonyautoxins (GTX) and C toxins obtained from contaminated mussels and stored at different temperatures in lyophilized samples. Analyses of extracts from mussels contaminated with paralytic shellfish poison (PSP) indicated the presence of gonyautoxins as the major component in red tides of the North-West coast of Spain. These GTX and C toxins were extracted from contaminated mussels (Mytilus galloprovincialis Lmk) and partially purified by chromatography on Bio-Gel P-2 and Bio-Rex 70. The stability of these toxins was analysed by high performance liquid chromatography. GTX 4 and GTX 6 are the most stable toxins among GTX. We conclude that the lyophilization procedure is not the safest way to process most of the gonyautoxins. However, the lyophilization procedure made the C toxins unstable, so clearly this procedure must be rejected. PMID:7940588

  11. Drying effects on the antioxidant properties of polysaccharides obtained from Agaricus blazei Murrill.

    PubMed

    Wu, Songhai; Li, Feng; Jia, Shaoyi; Ren, Haitao; Gong, Guili; Wang, Yanyan; Lv, Zesheng; Liu, Yong

    2014-03-15

    Three polysaccharides (ABMP-F, ABMP-V, ABMP-A) were obtained from Agaricus blazei Murrill via methods such as freeze drying, vacuum drying and air drying, respectively. Their chemical compositions were examined, and antioxidant activities were investigated on the basis of assay for hydroxyl radical, DPPH radical, ABTS free radical scavenging ability and assay for Fe(2+)-chelating ability. Results showed that the three ABMPs have different physicochemical and antioxidant properties. Compared with air drying and vacuum drying methods, freeze drying method resulted to ABMP with higher neutral sugar, polysaccharide yield, uronic acid content, and stronger antioxidant abilities of hydroxyl radical, DPPH radical, ABTS radical scavenging and Fe(2+)-chelating. As a result, Agaricus blazei Murrill polysaccharides are natural antioxidant and freeze drying method serves as a good choice for the preparation of such polysaccharides and should be used to produce antioxidants for food industry.

  12. Sterilizing effects of cobalt-60 and cesium-137 radiation on male sea lampreys

    USGS Publications Warehouse

    Hanson, L.H.

    1990-01-01

    Male spawning-run sea lampreys Petromyzon marinus were exposed to various doses of cobalt-60 or cesium-137 radiation in an attempt to sterilize them for use in a program for controlling sea lampreys through the release of sterile males. Males captured and irradiated during the early part of the upstream migration were not effectively sterilized at the doses tested. After irradiation, the sea lampreys were more susceptible to fungal infections by Saprolegnia sp., and many died without attempting to spawn. Males captured and irradiated during the middle and late parts of the spawning migration were effectively sterilized at a dose of 2,000 rads. However, some radiation-induced mortality was observed in males captured and irradiated during the middle part of the spawning migration. Radiation is not as effective as the chemosterilant bisazir for sterilizing male sea lampreys.

  13. Methods for evaluating the effects of conduits at the surface of the sea

    NASA Astrophysics Data System (ADS)

    Fournier, Michel

    1994-07-01

    The propagation of radio waves in the atmosphere is determined by the index of refraction which is sensitive to the pressure, temperature and moisture of the air. In the vicinity of the surface of the sea, there is a strong gradient of moisture related to the evaporation of water; it gives rise to a fast decrease of the index of the air creating a conduit of propagation in vicinity of surface. A source located in the interior of the conduit (i.e., at an altitude ranging between that of the minimum of the modified index and sea surface) sees most of its energy remaining captive inside this conduit. This has as an operational consequence - a considerable increase in the range of the radio hardware working in the vicinity of the surface of the sea. In addition, the propagation inside the conduit is characterized by the presence of multipaths related to the successive reflection of the electromagnetic wave on the surface of the sea and the boundary of the conduit. What results is a series of reinforcements and attenuations of the field being propagated in the conduit. Taking into account the practical importance of these effects it is advisable to have suitable methods of evaluation. In this talk three methods are examined: (1) parabolic equation method, (2) method of modes, and (3) method of geometrical optics. The parabolic equation method consists of making an approximation of the wave equation by supposing that the field is propagated around a primary direction. Under these conditions one reduces the equation of propagation to a partial derivative equation of parabolic type which leads to an easy algorithm to work with. The method of modes makes it possible to carry out calculations in an entirely analytical way by supposing that the profile of the index follows a simple law. This method constitutes an analytical reference with respect to the two other methods which are numerical. The method of geometric optics is an asymptotic method. It consists of considering

  14. Topology-optimized multiple-disk resonators obtained using level set expression incorporating surface effects.

    PubMed

    Fujii, Garuda; Ueta, Tsuyoshi; Mizuno, Mamoru; Nakamura, Masayuki

    2015-05-01

    Topology-optimized designs of multiple-disk resonators are presented using level-set expression that incorporates surface effects. Effects from total internal reflection at the surfaces of the dielectric disks are precisely simulated by modeling clearly defined dielectric boundaries during topology optimization. The electric field intensity in optimal resonators increases to more than four and a half times the initial intensity in a resonant state, whereas in some cases the Q factor increases by three and a half times that for the initial state. Wavelength-scale link structures between neighboring disks improve the performance of the multiple-disk resonators. PMID:25969226

  15. Effects of Arctic Sea Ice Decline on Weather and Climate: A Review

    NASA Astrophysics Data System (ADS)

    Vihma, Timo

    2014-09-01

    The areal extent, concentration and thickness of sea ice in the Arctic Ocean and adjacent seas have strongly decreased during the recent decades, but cold, snow-rich winters have been common over mid-latitude land areas since 2005. A review is presented on studies addressing the local and remote effects of the sea ice decline on weather and climate. It is evident that the reduction in sea ice cover has increased the heat flux from the ocean to atmosphere in autumn and early winter. This has locally increased air temperature, moisture, and cloud cover and reduced the static stability in the lower troposphere. Several studies based on observations, atmospheric reanalyses, and model experiments suggest that the sea ice decline, together with increased snow cover in Eurasia, favours circulation patterns resembling the negative phase of the North Atlantic Oscillation and Arctic Oscillation. The suggested large-scale pressure patterns include a high over Eurasia, which favours cold winters in Europe and northeastern Eurasia. A high over the western and a low over the eastern North America have also been suggested, favouring advection of Arctic air masses to North America. Mid-latitude winter weather is, however, affected by several other factors, which generate a large inter-annual variability and often mask the effects of sea ice decline. In addition, the small sample of years with a large sea ice loss makes it difficult to distinguish the effects directly attributable to sea ice conditions. Several studies suggest that, with advancing global warming, cold winters in mid-latitude continents will no longer be common during the second half of the twenty-first century. Recent studies have also suggested causal links between the sea ice decline and summer precipitation in Europe, the Mediterranean, and East Asia.

  16. The in vivo trypanocidal effect of the diterpene 5-epi-icetexone obtained from Salvia gilliesii.

    PubMed

    Lozano, E; Strauss, M; Spina, R; Cifuente, D; Tonn, C; Rivarola, H W; Sosa, M A

    2016-02-01

    The search for new compounds with trypanocidal activity is crucial for the treatment of Chagas' disease. Previous in vitro studies have shown that the diterpene 5-epi-icetexone (ICTX) is active against Trypanosoma cruzi. The aim of this work was to evaluate the effect of ICTX on the parasites in infected mice, in an experimental model that mimics the acute phase of the disease. Swiss albino mice were infected with T. cruzi and treated daily with 10mg/kg/day ICTX (i.p.). Infected mice and mice injected with either saline or the vehicle DMSO were used as controls. Animals' survival and parasitemia were monitored once a week and histological studies were made at necropsy by the 5th week after infection. It was observed that the administration of ICTX increased the survival of mice infected, and induced a significant decrease in the parasitemia, as compared to controls. A similar protective effect was observed when animals were treated orally with benznidazole (BZN, used as a control of antiparasitic effect). By the 5th week post-infection, the presence of amastigote nests was observed within the fibers of the cardiac and skeletal muscle in controls, but not in animals treated with either ICTX or BZN. In addition, inflammatory infiltrates were observed in the tissues of controls, but not in animals treated with the drugs. We conclude that ICTX has an antiparasitic effect against T. cruzi, thus constituting an interesting option for the treatment of Chagas' disease, alone or combined with other drugs.

  17. Protective effects of a novel sea buckthorn wine on oxidative stress and hypercholesterolemia.

    PubMed

    Negi, Bharti; Kaur, Rajdeep; Dey, Gargi

    2013-02-01

    We developed a novel sea buckthorn wine containing significant in vitro free radical-scavenging activity. High-performance liquid chromatographic analysis of the sea buckthorn wine revealed that it contains high rutin, myricetin and quercetin levels compared to Cabernet Shiraz wine. In this study, we evaluated the protective effects of sea buckthorn wine against phorone-induced oxidative stress and high-cholesterol diet induced hypercholesterolemia in male LACA mice. Oral administration of sea buckthorn wine increased the redox ratio accompanied by reduction of oxidized glutathione levels leading to attenuation of phorone-induced oxidative stress. Furthermore, the sea buckthorn wine supplementation reduced hepatic lipid peroxidation and increased the superoxide dismutase activity indicating improved resistance to oxidative stress. In addition, high-cholesterol-fed mice administered with sea buckthorn wine exhibited a 197% increase in the HDL-C/LDL-C ratio compared to high-cholesterol diet treated mice. These studies provide important evidence that sea buckthorn wine exerts protective effects against oxidative stress and hypercholesterolemia. PMID:23096237

  18. Predictability of the Barents Sea ice in early winter: Remote effects of oceanic and atmospheric thermal conditions from the North Atlantic

    NASA Astrophysics Data System (ADS)

    Nakanowatari, Takuya; Sato, Kazutoshi; Inoue, Jun

    2015-04-01

    Predictability of sea ice concentrations (SICs) in the Barents Sea in early winter (November-December) is studied using canonical correlation analysis with atmospheric and ocean anomalies from the NCEP Climate Forecast System Reanalysis (NCEP-CFSR) data. We find that the highest prediction skill for a single-predictor model is obtained from the 13-month lead subsurface temperature at 200-m depth (T200) and the in-phase meridional surface wind (Vsfc). T200 skillfully predicts SIC variability in 35% of the Barents Sea, mainly in the eastern side. The T200 for negative sea-ice anomalies exhibits warm anomalies in the subsurface ocean temperature downstream of the Norwegian Atlantic Slope Current (NwASC) on a decadal timescale. The diagnostic analysis of NCEP-CFSR data suggests that the subsurface temperature anomaly stored below the thermocline during summer re-emerges in late autumn by atmospheric cooling and affects the sea-ice. The subsurface temperature anomaly of the NwASC is advected from the North Atlantic subpolar gyre over about 3 years. Vsfc skillfully predicts SIC variability in 32% of the Barents Sea, mainly in the western side. The Vsfc for the negative sea-ice anomalies exhibits southerly wind anomalies. Vsfc is related to the large-scale atmospheric circulation patterns from the subtropical North Atlantic to the Eurasian continent. Our study suggests that both atmospheric and oceanic remote effects have a potential impact on the forecasting accuracy of SIC.

  19. Molecular properties and prebiotic effect of inulin obtained from artichoke (Cynara scolymus L.).

    PubMed

    López-Molina, Dorotea; Navarro-Martínez, María Dolores; Rojas Melgarejo, Francisco; Hiner, Alexander N P; Chazarra, Soledad; Rodríguez-López, José Neptuno

    2005-06-01

    A high molecular weight inulin has been prepared from artichoke (Cynara scolymus L.) agroindustrial wastes using environmentally benign aqueous extraction procedures. Physico-chemical analysis of the properties of artichoke inulin was carried out. Its average degree of polymerization was 46, which is higher than for Jerusalem artichoke, chicory, and dahlia inulins. GC-MS confirmed that the main constituent monosaccharide in artichoke inulin was fructose and its degradation by inulinase indicated that it contained the expected beta-2,1-fructan bonds. The FT-IR spectrum was identical to that of chicory inulin. These data indicate that artichoke inulin will be suitable for use in a wide range of food applications. The health-promoting prebiotic effects of artichoke inulin were demonstrated in an extensive microbiological study showing a long lasting bifidogenic effect on Bifidobacterium bifidum ATCC 29521 cultures and also in mixed cultures of colonic bacteria.

  20. Molecular properties and prebiotic effect of inulin obtained from artichoke (Cynara scolymus L.).

    PubMed

    López-Molina, Dorotea; Navarro-Martínez, María Dolores; Rojas Melgarejo, Francisco; Hiner, Alexander N P; Chazarra, Soledad; Rodríguez-López, José Neptuno

    2005-06-01

    A high molecular weight inulin has been prepared from artichoke (Cynara scolymus L.) agroindustrial wastes using environmentally benign aqueous extraction procedures. Physico-chemical analysis of the properties of artichoke inulin was carried out. Its average degree of polymerization was 46, which is higher than for Jerusalem artichoke, chicory, and dahlia inulins. GC-MS confirmed that the main constituent monosaccharide in artichoke inulin was fructose and its degradation by inulinase indicated that it contained the expected beta-2,1-fructan bonds. The FT-IR spectrum was identical to that of chicory inulin. These data indicate that artichoke inulin will be suitable for use in a wide range of food applications. The health-promoting prebiotic effects of artichoke inulin were demonstrated in an extensive microbiological study showing a long lasting bifidogenic effect on Bifidobacterium bifidum ATCC 29521 cultures and also in mixed cultures of colonic bacteria. PMID:15960982

  1. Communication: comparing ab initio methods of obtaining effective U parameters for closed-shell materials.

    PubMed

    Yu, Kuang; Carter, Emily A

    2014-03-28

    The density functional theory (DFT)+U method is an efficient and effective way to calculate the ground-state properties of strongly correlated transition metal compounds, with the effective U parameters typically determined empirically. Two ab initio methods have been developed to compute the U parameter based on either constrained DFT (CDFT) or unrestricted Hartree-Fock (UHF) theory. Previous studies have demonstrated the success of both methods in typical open-shell materials such as FeO and NiO. In this Communication we report numerical instability issues that arise for the CDFT method when applied to closed-shell transition metals, by using ZnO and Cu2O as examples. By contrast, the UHF method behaves much more robustly for both closed- and open-shell materials, making it more suitable for treating closed-shell transition metals, as well as main group elements. PMID:24697417

  2. Communication: Comparing ab initio methods of obtaining effective U parameters for closed-shell materials

    NASA Astrophysics Data System (ADS)

    Yu, Kuang; Carter, Emily A.

    2014-03-01

    The density functional theory (DFT)+U method is an efficient and effective way to calculate the ground-state properties of strongly correlated transition metal compounds, with the effective U parameters typically determined empirically. Two ab initio methods have been developed to compute the U parameter based on either constrained DFT (CDFT) or unrestricted Hartree-Fock (UHF) theory. Previous studies have demonstrated the success of both methods in typical open-shell materials such as FeO and NiO. In this Communication we report numerical instability issues that arise for the CDFT method when applied to closed-shell transition metals, by using ZnO and Cu2O as examples. By contrast, the UHF method behaves much more robustly for both closed- and open-shell materials, making it more suitable for treating closed-shell transition metals, as well as main group elements.

  3. The in vivo trypanocidal effect of the diterpene 5-epi-icetexone obtained from Salvia gilliesii.

    PubMed

    Lozano, E; Strauss, M; Spina, R; Cifuente, D; Tonn, C; Rivarola, H W; Sosa, M A

    2016-02-01

    The search for new compounds with trypanocidal activity is crucial for the treatment of Chagas' disease. Previous in vitro studies have shown that the diterpene 5-epi-icetexone (ICTX) is active against Trypanosoma cruzi. The aim of this work was to evaluate the effect of ICTX on the parasites in infected mice, in an experimental model that mimics the acute phase of the disease. Swiss albino mice were infected with T. cruzi and treated daily with 10mg/kg/day ICTX (i.p.). Infected mice and mice injected with either saline or the vehicle DMSO were used as controls. Animals' survival and parasitemia were monitored once a week and histological studies were made at necropsy by the 5th week after infection. It was observed that the administration of ICTX increased the survival of mice infected, and induced a significant decrease in the parasitemia, as compared to controls. A similar protective effect was observed when animals were treated orally with benznidazole (BZN, used as a control of antiparasitic effect). By the 5th week post-infection, the presence of amastigote nests was observed within the fibers of the cardiac and skeletal muscle in controls, but not in animals treated with either ICTX or BZN. In addition, inflammatory infiltrates were observed in the tissues of controls, but not in animals treated with the drugs. We conclude that ICTX has an antiparasitic effect against T. cruzi, thus constituting an interesting option for the treatment of Chagas' disease, alone or combined with other drugs. PMID:26341064

  4. Effects of systematic errors on the mixing ratios of trace gases obtained from occulation spectra

    NASA Technical Reports Server (NTRS)

    Shaffer, W. A.; Shaw, J. H.; Farmer, C. B.

    1983-01-01

    The influence of systematic errors in the parameters of the models describing the geometry and the atmosphere on the profiles of trace gases retrieved from simulated solar occultation spectra, collected at satellite altitudes, is investigated. Because of smearing effects and other uncertainties, it may be preferable to calibrate the spectra internally by measuring absorption lines of an atmospheric gas such as CO2 whose vertical distribution is assumed rather than to relay on externally supplied information.

  5. Packaging effective community service delivery: the utility of mandates and contracts in obtaining administrative cooperation.

    PubMed

    Woodard, K L

    1994-01-01

    Voluntary agreements, mandates, and contracts integrate networks of social service organizations, allowing them to function as coordinated wholes. The author reviews the history of contracting and mandating in the public sector. It is hypothesized that contracted relationships formalize agreements between local organizations dependent on others. Mandated relationships are perceived to be important by policy-makers at a state or federal level. The differential acceptance and rejection of these relationships in the community is explored. Data from social service agencies are used to compare administrators' assessments of the effectiveness of mandated and contracted relationships used to coordinate a group of agencies delivering services to children. When a mandated relationship has been formalized into a contract by a local administrator the perceived effectiveness of that relationship is higher than any other relationship in the community. If the mandated relationship has not been formalized by a contract this relationship is perceived to be the least effective. Important mandated inter-organizational ties without monetary incentives are less likely to work. Local administrators having developed the contracted ties see these ties as producing a higher level of performance. PMID:10138341

  6. 23 CFR 669.13 - Effect of failure to certify or to adequately obtain proof-of-payment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 23 Highways 1 2012-04-01 2012-04-01 false Effect of failure to certify or to adequately obtain proof-of-payment. 669.13 Section 669.13 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS ENFORCEMENT OF HEAVY VEHICLE USE TAX § 669.13 Effect of...

  7. Braking indices of pulsars obtained in the presence of an effective force

    NASA Astrophysics Data System (ADS)

    Magalhaes, N. S.; Okada, A. S.; Frajuca, C.

    2016-10-01

    Braking indices of pulsars present a scientific challenge as their theoretical calculation is still an open problem. In this paper, we report results of a study regarding such calculation which adapts the canonical model (which admits that pulsars are rotating magnetic dipoles) basically by introducing a compensating component in the energy conservation equation of the system. This component would correspond to an effective force that varies with the first power of the tangential velocity of the pulsar's crust. We test the proposed model using data available and predict braking indices values for different stars. We comment on the high braking index recently measured of the pulsar J1640-4631.

  8. Use of toroidal monochromators in a hybrid XRF system to obtain increased effectiveness ratios

    NASA Astrophysics Data System (ADS)

    Furnas, Thomas C.; Lambert, Maurice C.; Furnas, Richard E.

    A combination of energy and wavelength dispersive components in a new hybrid XRF system has yielded a tenfold improvement in the effectiveness ratio (number of counts in the region of interest divided by the total number of other counts collected by the detector and electronics) over the use of a detector directly viewing a specimen illuminated by primary X-rays with or without filters or by secondary targets. Monochromatic illumination of the specimen allows the use of a fundamental parameters technique for quantitative analysis without the need for a multitude of standards.

  9. Conceptual and methodological challenges to integrating SEA and cumulative effects assessment

    SciTech Connect

    Gunn, Jill; Noble, Bram F.

    2011-03-15

    The constraints to assessing and managing cumulative environmental effects in the context of project-based environmental assessment are well documented, and the potential benefits of a more strategic approach to cumulative effects assessment (CEA) are well argued; however, such benefits have yet to be clearly demonstrated in practice. While it is widely assumed that cumulative effects are best addressed in a strategic context, there has been little investigation as to whether CEA and strategic environmental assessment (SEA) are a 'good fit' - conceptually or methodologically. This paper identifies a number of conceptual and methodological challenges to the integration of CEA and SEA. Based on results of interviews with international experts and practitioners, this paper demonstrates that: definitions and conceptualizations of CEA are typically weak in practice; approaches to effects aggregation vary widely; a systems perspective lacks in both SEA and CEA; the multifarious nature of SEA complicates CEA; tiering arrangements between SEA and project-based assessment are limited to non-existing; and the relationship of SEA to regional planning remains unclear.

  10. Effects of Wind and Sea Ice Drift on the Seasonal Variation of Warm Circumpolar Deep Water in the Amundsen Sea

    NASA Astrophysics Data System (ADS)

    Kim, T. W.; Wahlin, A.; Ha, H. K.; Lee, S.; Lee, J. H.

    2014-12-01

    We examined the effect of wind and sea ice on seasonal variation in the thickness of circumpolar deep water, to better understand the processes causing mass loss in the West Antarctic ice sheet (WAIS). Spatial and temporal variation of the layer of warm and salty circumpolar deep water (CDW) at the center of the Amundsen Shelf was measured during two oceanographic surveys and a two-year mooring deployment. A hydrographic transect from the deep ocean, across the shelf break, and into the Dotson Trough shows a local elevation of the warm deep water layer at the shelf break. On the shelf, the water flows south-east along the trough. The thickness of the warm layer displays seasonal variation with maximum thickness in austral summer and minimum thickness in austral winter. The variation in warm layer thickness gives rise to a seasonal variation of the modified CDW heat content. In order to investigate the effects of wind and sea ice drift on the heat content, ocean surface stress was calculated using the ERA interim reanalysis wind data and observed sea ice velocity and concentration from satellites. The Ekman pumping velocity was calculated from the ocean surface stress field. The Ekman pumping at the shelf break, where the warm layer is elevated, shows a strong seasonal variation coinciding with the mooring data. The average wind field is eastward north of the shelf break and westward south of the shelf break during all seasons. The main effect of a layer of sea ice (between the wind and the water) is to reduce the surface stress which can intensify the horizontal gradient of surface stress at the marginal ice zone. This creates a divergence of the Ekman transport and a positive Ekman pumping at the marginal ice zone, if the wind direction is eastward. From February to April, a marginal ice zone close to the shelf break gives rise to a positive Ekman pumping that may explain the seasonal signal seen in the mooring data. At northern boundaries of coastal polynya

  11. Remanence anisotropy effect on the palaeointensity results obtained from various archaeological materials, excluding pottery

    NASA Astrophysics Data System (ADS)

    Kovacheva, M.; Chauvin, A.; Jordanova, N.; Lanos, P.; Karloukovski, V.

    2009-06-01

    The effect of magnetic anisotropy on the palaeointensity results has been evaluated in different materials, including samples from archaeological structures of various ages, such as baked clay from prehistoric domestic ovens or pottery kilns, burnt soil from ancient fires, and bricks and bricks or tiles used in the kiln's construction. The remanence anisotropy was estimated by the thermoremanent (TRM) anisotropy tensor and isothermal remanence (IRM) tensor methods. The small anisotropy effect (less than 5%) observed in the palaeointensity results of baked clay from the relatively thin prehistoric oven's floors estimated previously through IRM anisotropy was confirmed by TRM anisotropy of this material. The new results demonstrate the possibility of using IRM anisotropy evaluation to correct baked clay palaeointensity data instead of the more difficult to determine TRM anisotropy ellipsoid. This is not always the case for the palaeointensity results from bricks and tiles. The anisotropy correction to palaeointensity results seems negligible for materials other than pottery. It would therefore appear that the palaeointensity determination is more sensitive to the degree of remanence anisotropy P and the angle between the natural remanent magnetization (NRM) vector and the laboratory field direction, than to the angle between the NRM and the maximum axis of the remanence anisotropy ellipsoid (Kmax).

  12. Analysis of the Magnetocaloric Effect in Powder Samples Obtained by Ball Milling

    NASA Astrophysics Data System (ADS)

    Blázquez, J. S.; Ipus, J. J.; Moreno-Ramírez, L. M.; Borrego, J. M.; Lozano-Pérez, S.; Franco, V.; Conde, C. F.; Conde, A.

    2015-06-01

    Since the discovery of the giant magnetocaloric effect (MCE) close to room temperature in FeRh and particularly in Gd5Si2Ge2 compounds, the study of this phenomenon has experienced an exponential growth. Among the different techniques used to produce magnetocaloric materials, ball milling has been shown as a very versatile one and presents several advantages over other preparation techniques ( e.g., easy scale-up to industrial production). Although a general decrease of the peak value of the magnetic entropy change is observed for milled samples, it can be compensated by the large broadening of the MCE peak, leading to an increase of the refrigeration capacity. In this short review, several aspects inherent to powder samples affecting MCE will be discussed, such as the relevant effect of the demagnetizing field, the possible multiphase character, and the presence of Curie temperature distributions. In mechanically alloyed samples, the two latter factors are typically affected by the degree of integration of the different starting constituents.

  13. Antihelmintic effects of nutmeg (Myristica fragans) on Anisakis simplex L3 larvae obtained from Micromesistius potassou.

    PubMed

    López, Víctor; Gerique, Javier; Langa, Elisa; Berzosa, César; Valero, Marta Sofía; Gómez-Rincón, Carlota

    2015-06-01

    Anisakis simplex is a foodborne pathogen that can produce human infections and allergic reactions due to the high consumption of raw fish. The seeds of Myristica fragans (Myristicaceae), popularly known as nutmeg, are worldwide used as a culinary spice due to its flavour and properties in food preservation. A nutmeg extract was prepared, analyzed, screened for cytotoxicity and tested against Anisakis simplex L3 larvae. In order to detect the biologically active constituents of the extract, myristicin was tested on the larvae. An acetylcholinesterase inhibition bioassay was also carried out to investigate the antihelmintic mechanism of action. Our results demonstrate that nutmeg exerts antihelmintic effects on Anisakis simplex, being myristicin one of the active compounds. The extract induced a high rate of dead anisakis at concentrations between 0.5 and 0.7 mg/ml without being considered cytotoxic; however, an inhibition of acetylcholinesterase was discarded as the molecular mechanism involved in the activity.

  14. Lateral conduction effects on heat-transfer data obtained with the phase-change paint technique

    NASA Technical Reports Server (NTRS)

    Maise, G.; Rossi, M. J.

    1974-01-01

    A computerized tool, CAPE, (Conduction Analysis Program using Eigenvalues) has been developed to account for lateral heat conduction in wind tunnel models in the data reduction of the phase-change paint technique. The tool also accounts for the effects of finite thickness (thin wings) and surface curvature. A special reduction procedure using just one time of melt is also possible on leading edges. A novel iterative numerical scheme was used, with discretized spatial coordinates but analytic integration in time, to solve the inverse conduction problem involved in the data reduction. A yes-no chart is provided which tells the test engineer when various corrections are large enough so that CAPE should be used. The accuracy of the phase-change paint technique in the presence of finite thickness and lateral conduction is also investigated.

  15. Antihelmintic effects of nutmeg (Myristica fragans) on Anisakis simplex L3 larvae obtained from Micromesistius potassou.

    PubMed

    López, Víctor; Gerique, Javier; Langa, Elisa; Berzosa, César; Valero, Marta Sofía; Gómez-Rincón, Carlota

    2015-06-01

    Anisakis simplex is a foodborne pathogen that can produce human infections and allergic reactions due to the high consumption of raw fish. The seeds of Myristica fragans (Myristicaceae), popularly known as nutmeg, are worldwide used as a culinary spice due to its flavour and properties in food preservation. A nutmeg extract was prepared, analyzed, screened for cytotoxicity and tested against Anisakis simplex L3 larvae. In order to detect the biologically active constituents of the extract, myristicin was tested on the larvae. An acetylcholinesterase inhibition bioassay was also carried out to investigate the antihelmintic mechanism of action. Our results demonstrate that nutmeg exerts antihelmintic effects on Anisakis simplex, being myristicin one of the active compounds. The extract induced a high rate of dead anisakis at concentrations between 0.5 and 0.7 mg/ml without being considered cytotoxic; however, an inhibition of acetylcholinesterase was discarded as the molecular mechanism involved in the activity. PMID:25890576

  16. Effect of using different cover image quality to obtain robust selective embedding in steganography

    NASA Astrophysics Data System (ADS)

    Abdullah, Karwan Asaad; Al-Jawad, Naseer; Abdulla, Alan Anwer

    2014-05-01

    One of the common types of steganography is to conceal an image as a secret message in another image which normally called a cover image; the resulting image is called a stego image. The aim of this paper is to investigate the effect of using different cover image quality, and also analyse the use of different bit-plane in term of robustness against well-known active attacks such as gamma, statistical filters, and linear spatial filters. The secret messages are embedded in higher bit-plane, i.e. in other than Least Significant Bit (LSB), in order to resist active attacks. The embedding process is performed in three major steps: First, the embedding algorithm is selectively identifying useful areas (blocks) for embedding based on its lighting condition. Second, is to nominate the most useful blocks for embedding based on their entropy and average. Third, is to select the right bit-plane for embedding. This kind of block selection made the embedding process scatters the secret message(s) randomly around the cover image. Different tests have been performed for selecting a proper block size and this is related to the nature of the used cover image. Our proposed method suggests a suitable embedding bit-plane as well as the right blocks for the embedding. Experimental results demonstrate that different image quality used for the cover images will have an effect when the stego image is attacked by different active attacks. Although the secret messages are embedded in higher bit-plane, but they cannot be recognised visually within the stegos image.

  17. Sea Ice Friction: The Effect of Ice Rubble

    NASA Astrophysics Data System (ADS)

    Scourfield, S.; Sammonds, P. R.; Lishman, B.; Riska, K.; Marchenko, A. V.

    2015-12-01

    Ice deformation processes in the Arctic often generate ice rubble, and situations arise where ice fragments of varying size separate sea ice floes. While the shear forces between sea ice floes in direct contact with each other are controlled by ice-ice friction, what is not known is how the slip of the floes is affected by the presence of rubble between the sliding surfaces. We present the result of field experiments undertaken on fjord ice in Svea, Svalbard, which investigated the velocity and hold time dependence of sea ice friction involving ice gouge. Average air temperature for the duration of time in which experiments were run was -12.4°C, and the thickness of the level fjord ice was 70 cm. A double-direct-shear experiment was done on floating sea ice in the field, with the addition of rubble ice between the sliding surfaces. This was achieved by moving a floating ice block through a channel of open water whilst subjected to normal loading, which was transferred through regions of ice rubble on both sides of the mobile block. The ice rubble regions were 30 cm deep and 50 cm wide. The displacement of the block and the force needed to move the block were measured. The rate dependence of friction was investigated for speeds of 10-3 to 10-2 ms-1. To investigate the state dependence of friction, slide-hold-slide (SHS) tests were conducted for hold times ranging from 1 second to 18 hours. When comparing the results from these experiments with a model for ice friction presented by Schulson and Fortt (2013), similar behaviour is seen at low hold times, where the peak coefficient of friction has a linear relationship with the logarithm of hold time. This is not the case for long hold times, however, and we attribute this to thermal consolidation of the ice rubble region.

  18. SEA effectiveness for landscape and master planning: An investigation in Sardinia

    SciTech Connect

    De Montis, Andrea; Ledda, Antonio; Caschili, Simone; Ganciu, Amedeo; Barra, Mario

    2014-07-01

    The Italian administrative bodies and planning agencies have embraced with mixed feedbacks the introduction of Strategic Environmental Assessment (SEA) through the European Directive 2001/42/EC. Concurrently, regional and local spatial planning practice have been characterized by a new approach inspired by landscape planning. The Italian region of Sardinia has been one of the pioneering administrative bodies in the Italian and European arena that has adopted landscape principles for the construction of its regional master plan (PPR, Piano Paesaggistico Regionale). Municipalities are now carrying out the review of their master plans to the PPR's prescriptions and indications. Against this background, the aim of this paper is to assess the level of SEA implementation in the municipal master plans of Sardinia, six years after the approval of the PPR. Rooted in the SEA international literature we construct a modular and adaptable on-line survey for officers involved in the review of municipal master plans. The results show that many Sardinian municipalities have not reviewed their master plans to the PPR's regulations yet and only a few municipalities have started this review process according to the SEA procedure. - Highlights: • We study strategic environmental assessment (SEA) effectiveness on land use plans • Four SEA implementation key issues are drawn from international literature • Data collection has included an on-line survey with close and open questions • Results indicate that SEA has been poorly implemented in landscape and master plans • Weak aspects include planning alternatives, financial resources, and monitoring.

  19. Dehydration as an effective treatment for brevetoxicosis in loggerhead sea turtles (Caretta caretta).

    PubMed

    Manire, Charles A; Anderson, Eric T; Byrd, Lynne; Fauquier, Deborah A

    2013-06-01

    Harmful algal blooms are known to cause morbidity and mortality to a large number of marine and estuarine organisms worldwide, including fish and marine mammals, birds, and turtles. The effects of these algal blooms on marine organisms are due to the various toxins produced by the different algal species. In southwest Florida, frequent blooms of the dinoflagellate Karenia brevis, which produces neurotoxins known as brevetoxins, cause widespread fish kills and affect many marine animals. In 2005-2007, numerous sea turtles of several species underwent treatment for brevetoxicosis at the Sea Turtle Rehabilitation Hospital. In green sea turtles, Chelonia mydas, and Kemp's ridley sea turtles, Lepidochelys kempii, symptoms associated with brevetoxicosis were limited to neurologic signs, such as the inability to control the head (head bobbing) and nervous twitching. For these turtles, treatment involved removing the turtles from the environment containing the toxins and providing short-term supportive care. In loggerhead sea turtles, Caretta caretta, symptoms were more generalized; thus, a similar approach was unsuccessful, as was routine treatment for general toxicosis. Loggerhead sea turtles had more extreme neurologic symptoms including coma, and other symptoms that included generalized edema, conjunctival edema, and cloacal or penile prolapse. Treatment of brevetoxicosis in loggerhead sea turtles required a therapeutic regimen that initially included dehydration and systemic antihistamine treatment followed by supportive care.

  20. Investigating the Sensitivity of Arctic Sea Ice to Variability in Early Summer Cloud Radiative Effect

    NASA Astrophysics Data System (ADS)

    King, M. D.

    2015-12-01

    Arctic sea ice is a highly sensitive and integral component of the climate system. The observed decline of sea ice in recent decades has affected Arctic ecosystems, transportation, and atmospheric processes. For these reasons, the development of skillful seasonal model predictions is essential, particularly for the early autumn when Arctic ice retreats to its minimum extent. However, a high degree of temporal and spatial variability has made sea ice predictions challenging. Arctic clouds become a large source of this variability by altering the amount of insolation and longwave radiation that is received at the surface. The goal of this research is to identify the predictive value of early summer cloud radiative effect (CRE) on autumnal sea ice extent. Absorbed solar radiation at the surface is most sensitive to cloud cover and composition during months of peak solar insolation, and may precondition the melting momentum of the sea ice in the subsequent months. Satellite data products, such as CERES, are used to investigate trends in cloud cover and radiative properties over the entire Arctic, as well as in several specific Arctic regions. This data, along with satellite sea ice concentration products, will be used to investigate the sensitivity of autumnal sea ice extent to changes in CRE throughout the melt season. The influence of relevant, larger-scale climate oscillations on atmospheric regimes and resulting cloud distribution will also be given consideration.

  1. Dehydration as an effective treatment for brevetoxicosis in loggerhead sea turtles (Caretta caretta).

    PubMed

    Manire, Charles A; Anderson, Eric T; Byrd, Lynne; Fauquier, Deborah A

    2013-06-01

    Harmful algal blooms are known to cause morbidity and mortality to a large number of marine and estuarine organisms worldwide, including fish and marine mammals, birds, and turtles. The effects of these algal blooms on marine organisms are due to the various toxins produced by the different algal species. In southwest Florida, frequent blooms of the dinoflagellate Karenia brevis, which produces neurotoxins known as brevetoxins, cause widespread fish kills and affect many marine animals. In 2005-2007, numerous sea turtles of several species underwent treatment for brevetoxicosis at the Sea Turtle Rehabilitation Hospital. In green sea turtles, Chelonia mydas, and Kemp's ridley sea turtles, Lepidochelys kempii, symptoms associated with brevetoxicosis were limited to neurologic signs, such as the inability to control the head (head bobbing) and nervous twitching. For these turtles, treatment involved removing the turtles from the environment containing the toxins and providing short-term supportive care. In loggerhead sea turtles, Caretta caretta, symptoms were more generalized; thus, a similar approach was unsuccessful, as was routine treatment for general toxicosis. Loggerhead sea turtles had more extreme neurologic symptoms including coma, and other symptoms that included generalized edema, conjunctival edema, and cloacal or penile prolapse. Treatment of brevetoxicosis in loggerhead sea turtles required a therapeutic regimen that initially included dehydration and systemic antihistamine treatment followed by supportive care. PMID:23805564

  2. Electrical conductivity of graphite oxide nanoplatelets obtained from bamboo: Effect of the deoxidation degree

    NASA Astrophysics Data System (ADS)

    Gross, K.; Prias-Barragan, J. J.; Sangiao, S.; de Teresa, J. M.; Lajaunie, L.; Arenal, R.; Ariza-Calderón, H.; Prieto, P.

    Given the high interest in the fabrication and application of carbon-based materials, we present a new and cost-effective method for the synthesis of graphite oxide nanoplatelets (GONP) using bamboo pyroligneous acid (BPA) as source. GONP-BPA present lateral dimensions of 5-100 micro-meter and thickness less than 80 nm, as confirmed by TEM. EEL spectra show that locally the carbon is mainly in sp2 bonding configuration and confirm a short/medium range crystalline order. Elemental analysis by EDX confirms the presence of oxygen in an atomic percentage ranging from 17 to 5%. For electrical characterization, single platelets were contacted by focused-ion-beam-induced deposition of Pt nanowires. The four-point probe electrical conductivity shows a direct correlation with the oxygen percentage. Three orders of magnitude conductivity rise is observed by the oxygen reduction, reaching a value of 2.3x103 S/m at the final deoxidation degree. The results suggest that GONP-BPA could be used in the development of advanced devices and sensors.

  3. Single molecular resistive switch obtained via sliding multiple anchoring points and varying effective wire length.

    PubMed

    Kiguchi, Manabu; Ohto, Tatsuhiko; Fujii, Shintaro; Sugiyasu, Kazunori; Nakajima, Shigeto; Takeuchi, Masayuki; Nakamura, Hisao

    2014-05-21

    A single molecular resistive (conductance) switch via control of anchoring positions was examined by using a molecule consisting of more than two same anchors. For this purpose, we adopted the covered quaterthiophene (QT)-based molecular wire junction. The QT-based wire consisted of two thiophene ring anchors on each side; thus, shift of anchors was potentially possible without a change in the binding modes and distortion of the intramolecular structure. We observed three distinct conductance states by using scanning tunneling microscope-based break junction technique. A detailed analysis of the experimental data and first-principles calculations revealed that the mechanism of the resistive switch could be explained by standard length dependence (exponential decay) of conductance. Here, the length is the distance between the anchoring points, i.e., length of the bridged π-conjugated backbone. Most importantly, this effective tunneling length was variable via only controlling the anchoring positions in the same molecule. Furthermore, we experimentally showed the possibility of a dynamic switch of anchoring positions by mechanical control. The results suggested a distinct strategy to design functional devices via contact engineering.

  4. Deuterated protein folds obtained directly from unassigned nuclear overhauser effect data.

    PubMed

    Bermejo, Guillermo A; Llinás, Miguel

    2008-03-26

    We demonstrate the feasibility of determining the global fold of a highly deuterated protein from unassigned experimental NMR nuclear Overhauser effect (NOE) data only. The method relies on the calculation of a spatial configuration of covalently unconnected protons-a "cloud"-directly from unassigned distance restraints derived from 13C- and 15N-edited NOESY spectra. Each proton in the cloud, labeled by its chemical shift and that of the directly bound 13C or 15N, is subsequently mapped to specific atoms in the protein. This is achieved via graph-theoretical protocols that search for connectivities in graphs that encode the structural information within the cloud. The peptidyl HN chain is traced by seeking for all possible routes and selecting the one that yields the minimal sum of sequential distances. Complete proton identification in the cloud is achieved by linking the side-chain protons to proximal main-chain HNs via bipartite graph matching. The identified protons automatically yield the NOE assignments, which in turn are used for structure calculation with RosettaNMR, a protocol that incorporates structural bias derived from protein databases. The method, named Sparse-Constraint CLOUDS, was applied to experimental NOESY data on the 58-residue Z domain of staphylococcal protein A. The generated structures are of similar accuracy to those previously reported, which were derived via a conventional approach involving a larger NMR data set. Additional tests were performed on seven reported protein structures of various folds, using restraint lists simulated from the known atomic coordinates.

  5. Chemical contaminants in the Wadden Sea: Sources, transport, fate and effects

    NASA Astrophysics Data System (ADS)

    Laane, R. W. P. M.; Vethaak, A. D.; Gandrass, J.; Vorkamp, K.; Köhler, A.; Larsen, M. M.; Strand, J.

    2013-09-01

    The Wadden Sea receives contaminants from various sources and via various transport routes. The contaminants described in this overview are various metals (Cd, Cu, Hg, Pb and Zn) and various organic contaminants (polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and lindane (hexachlorocyclohexane, γ-HCH)). In addition, information is presented about other and emerging contaminants such as antifouling biocides (e.g. TBT and Irgarol), brominated flame retardants (BFRs), poly- and perfluorinated compounds (PFCs) and pharmaceutical and personal care products (PPCPs). Special attention is given to biogeochemical processes that contribute to the mobilization of contaminants in the surface sediments of the Wadden Sea. Finally, the effects on organisms of contaminants are reviewed and discussed. The main source of contaminants in the Wadden Sea are the rivers Rhine (via de Dutch coastal zone), Elbe and Weser. The Wadden Sea is not a sink for contaminants and adsorbed contaminants are transported from east to west. The surface sediments of the Wadden Sea are an important source for contaminants to the water above. The input and concentration of most contaminants have significantly decreased in water, sediments, organisms (e.g., mussel, flounder and bird eggs) in various parts of the Wadden Sea in the last three decades. Remarkably, the Cd concentration in mussels is increasing the last decades. In recent decades, the effects of contaminants on organisms (e.g., flounder, seal) have fallen markedly. Most of the affected populations have recovered, except for TBT induced effects in snails. Little is known about the concentration and effects of most emerging contaminants and the complex environmental mixtures of contaminants. It is recommended to install an international coordinated monitoring programme for contaminants and their effects in the whole Wadden Sea and to identify the chemical contaminants that really cause the effect.

  6. 'Direct PCR' optimization yields a rapid, cost-effective, nondestructive and efficient method for obtaining DNA barcodes without DNA extraction.

    PubMed

    Wong, Wing Hing; Tay, Ywee Chieh; Puniamoorthy, Jayanthi; Balke, Michael; Cranston, Peter S; Meier, Rudolf

    2014-11-01

    Macroinvertebrates that are collected in large numbers pose major problems in basic and applied biodiversity research: identification to species via morphology is often difficult, slow and/or expensive. DNA barcodes are an attractive alternative or complementary source of information. Unfortunately, obtaining DNA barcodes from specimens requires many steps and thus time and money. Here, we promote a short cut to DNA barcoding, that is, a nondestructive PCR method that skips DNA extraction ('direct PCR') and that can be used for a broad range of invertebrate taxa. We demonstrate how direct PCR can be optimized for the larvae and adults of nonbiting midges (Diptera: Chironomidae), a typical invertebrate group that is abundant, contains important bioindicator species, but is difficult to identify based on morphological features. After optimization, direct PCR yields high PCR success rates (>90%), preserves delicate morphological features (e.g. details of genitalia, and larval head capsules) while allowing for the recovery of genomic DNA. We also document that direct PCR can be successfully optimized for a wide range of other invertebrate taxa that need routine barcoding (flies: Culicidae, Drosophilidae, Dolichopodidae, Sepsidae; sea stars: Oreasteridae). Key for obtaining high PCR success rates is optimizing (i) tissue quantity, (ii) body part, (iii) primer pair and (iv) type of Taq polymerase. Unfortunately, not all invertebrates appear suitable because direct PCR has low success rates for other taxa that were tested (e.g. Coleoptera: Dytiscidae, Copepoda, Hymenoptera: Formicidae and Odonata). It appears that the technique is less successful for heavily sclerotized insects and/or those with many exocrine glands. PMID:24816169

  7. Assessment of the toxic effect exerted by fluorescent pseudomonads on embryos and larvae of the sea urchin Strongylocentrotus nudus.

    PubMed

    Beleneva, I A; Shamshurina, E V; Eliseikina, M G

    2015-05-01

    Strains of bacteria capable of growing on artificial culture media were isolated from the fouling of brass plates submerged in Nha Trang Bay, South China Sea, and from tissues of the seastar Distolasterias nipon, caught in Peter the Great Bay, Sea of Japan. According to the complex of data of genetic and physiological/biochemical analyzes, two strains of cultivated bacteria were identified by us as the species Pseudomonas aeruginosa, two strains as Pseudomonas fluorescens, and one strain as Ruegeria sp. It was shown that the cultivated strains of P. aeruginosa released exotoxins, particularly phenazine pigments, into the environment. Production of the toxins did not depend on presence of a target organism in the system and was aimed at regulation of interactions in the microbial community. The toxicity of the studied natural isolates of fluorescent pseudomonads was analyzed by using embryos and larvae of the sea urchin Strongylocentrotus nudus, which are the sensitive and dynamic toxicological sea-urchin embryo test (SET) system. As was established, exotoxins produced by the strains of P. aeruginosa inhibit activity of cilia in sea urchin larvae, as well as disturb processes of cell differentiation in embryos and larvae. Their toxic influence is accompanied by disturbances of protein synthesis and the disruptions of cytoskeleton in the course of zygote cleavage and larval development. Unlike P. aeruginosa, the strains of P. fluorescens and Ruegeria sp. did not exert the toxic effect on SET. The obtained data allow considering objects of the environment as the natural reservoir of opportunistic microorganisms posing a potential threat to human, whereas the use of SET for determination of toxicity of isolated bacteria provides an opportunity to study the mechanisms of their interactions with organisms in marine ecosystems.

  8. Modeling landscape dynamics and effects of sea-level rise on coastal wetlands of northwest Florida

    SciTech Connect

    Doyle, T.W.; Day, R.H.; Biagas, J.M.

    1997-06-01

    A research study to examine the ability to predict changes in coastal vegetation caused by sea level rise is very briefly summarized. A field survey was carried out on the northwest coast of Florida. A predictive elevation model was then generated from digitized US Geologic Survey 1:2400 hypsographic data using surface modeling techniques. Sea-level rise model simulations were generated to predict a likelihood index of habitat change and conversions under different scenarios. Maps were produced depicting location of the coastline and inland extent of salt marsh using a range of sea level rise rates through the year 2100. This modeling approach offers a technological tool to researchers and wetland managers for effective cumulative impact analysis of wetlands affected by sea-level rise.

  9. Global sea level rise and the greenhouse effect: might they be connected

    SciTech Connect

    Peltier, W.R.; Tushingham, A.M.

    1989-03-21

    Secular sea level trends extracted from tide gauge records of appropriately long duration demonstrate that global sea level may be rising at a rate in excess of 1 millimeter per year. However, because global coverage of the oceans by the tide gauge network is highly nonuniform and the tide gauge data reveal considerable spatial variability, there has been a well-founded reluctance to interpret the observed secular sea level rise as representing a signal of global scale that might be related to the greenhouse effect. When the tide gauge data are filtered so as to remove the contribution of ongoing glacial isostatic adjustment to the local sea level trend at each location, then the individual tide gauge records reveal sharply reduced geographic scatter and suggest that there is a globally coherent signal of strength 2.4 {+-} 0.90 millimeters per year that is active in the system. This signal could constitute an indication of global climate warming.

  10. Global sea level rise and the greenhouse effect: might they be connected?

    PubMed

    Peltier, W R; Tushingham, A M

    1989-05-19

    Secular sea level trends extracted from tide gauge records of appropriately long duration demonstrate that global sea level may be rising at a rate in excess of 1 millimeter per year. However, because global coverage of the oceans by the tide gauge network is highly nonuniform and the tide gauge data reveal considerable spatial variability, there has been a well-founded reluctance to interpret the observed secular sea level rise as representing a signal of global scale that might be related to the greenhouse effect. When the tide gauge data are filtered so as to remove the contribution of ongoing glacial isostatic adjustment to the local sea level trend at each location, then the individual tide gauge records reveal sharply reduced geographic scatter and suggest that there is a globally coherent signal of strength 2.4 +/- 0.90 millimeters per year that is active in the system. This signal could constitute an indication of global climate warming.

  11. On the effect of sea spray on the aerodynamic surface drag under severe winds

    NASA Astrophysics Data System (ADS)

    Troitskaya, Yuliya; Ezhova, Ekaterina; Soustova, Irina; Zilitinkevich, Sergej

    2016-05-01

    We investigate the effect of the sea spray on the air-sea momentum exchange during the entire "life cycle" of a droplet, torn off the crest of a steep surface wave, and its fall down to the water, in the framework of a model covering the following aspects of the phenomenon: (1) motion of heavy particle in the driving air flow (equations of motion); (2) structure of the wind field (wind velocity, wave-induced disturbances, turbulent fluctuations); (3) generation of the sea spray; and (4) statistics of droplets (size distribution, wind speed dependence). It is demonstrated that the sea spray in strong winds leads to an increase in the surface drag up to 40 % on the assumption that the velocity profile is neutral.

  12. Effects of co-fermentation by Saccharomyces cerevisiae and Issatchenkia orientalis on sea buckthorn juice.

    PubMed

    Negi, Bharti; Dey, Gargi

    2013-06-01

    This work relates to the development of a co-fermented product of sea buckthorn (Hippophae rhamnoides L.) with Saccharomyces cerevisiae and Issatchenkia orientalis. Besides malic acid degradation, the parameters of present production technology were also standardized with emphasis on the retainability of total phenolic content (TPC) of sea buckthorn juice. The effect of co-fermentation on physico-chemical characteristics, organic acids, flavonoids, TPC and antioxidant activities was studied. The high-performance liquid chromatography (HPLC) analysis showed 55% reduction in malic acid content after the co-fermentation of sea buckthorn juice. The TPC of sea buckthorn product was 2.18 g gallic acid equivalent (GAE)/l. The estimated scavenging effect on 2,2-diphenyl-1-picrylhydrazyl free radicals was 2.63 Trolox equivalent (TE) mmol/l. Ferric-reducing antioxidant power and 2,2'-azino-bis(3-ethylbenz-thiazoline-6-sulphonic acid) assays also showed that sea buckthorn product was on a par with commercial wines (Cabernet Shiraz and Beaujolais). We conclude that the process of co-fermentation resulted in a significant antioxidant potential of sea buckthorn product. PMID:23301774

  13. Effects of co-fermentation by Saccharomyces cerevisiae and Issatchenkia orientalis on sea buckthorn juice.

    PubMed

    Negi, Bharti; Dey, Gargi

    2013-06-01

    This work relates to the development of a co-fermented product of sea buckthorn (Hippophae rhamnoides L.) with Saccharomyces cerevisiae and Issatchenkia orientalis. Besides malic acid degradation, the parameters of present production technology were also standardized with emphasis on the retainability of total phenolic content (TPC) of sea buckthorn juice. The effect of co-fermentation on physico-chemical characteristics, organic acids, flavonoids, TPC and antioxidant activities was studied. The high-performance liquid chromatography (HPLC) analysis showed 55% reduction in malic acid content after the co-fermentation of sea buckthorn juice. The TPC of sea buckthorn product was 2.18 g gallic acid equivalent (GAE)/l. The estimated scavenging effect on 2,2-diphenyl-1-picrylhydrazyl free radicals was 2.63 Trolox equivalent (TE) mmol/l. Ferric-reducing antioxidant power and 2,2'-azino-bis(3-ethylbenz-thiazoline-6-sulphonic acid) assays also showed that sea buckthorn product was on a par with commercial wines (Cabernet Shiraz and Beaujolais). We conclude that the process of co-fermentation resulted in a significant antioxidant potential of sea buckthorn product.

  14. Bald eagles and sea otters in the Aleutian Archipelago: indirect effects of trophic cascades.

    PubMed

    Anthony, Robert G; Estes, James A; Ricca, Mark A; Miles, A Keith; Forsman, Eric D

    2008-10-01

    Because sea otters (Enhydra lutris) exert a wide array of direct and indirect effects on coastal marine ecosystems throughout their geographic range, we investigated the potential influence of sea otters on the ecology of Bald Eagles (Haliaeetus leucocephalus) in the Aleutian Islands, Alaska, USA. We studied the diets, productivity, and density of breeding Bald Eagles on four islands during 1993-1994 and 2000-2002, when sea otters were abundant and scarce, respectively. Bald Eagles depend on nearshore marine communities for most of their prey in this ecosystem, so we predicted that the recent decline in otter populations would have an indirect negative effect on diets and demography of Bald Eagles. Contrary to our predictions, we found no effects on density of breeding pairs on four islands from 1993-1994 to 2000-2002. In contrast, diets and diet diversity of Bald Eagles changed considerably between the two time periods, likely reflecting a change in prey availability resulting from the increase and subsequent decline in sea otter populations. The frequency of sea otter pups, rock greenling (Hexagammus lagocephalus), and smooth lumpsuckers (Aptocyclus ventricosus) in the eagle's diet declined with corresponding increases in Rock Ptarmigan (Lagopus mutus), Glaucous-winged Gulls (Larus glaucescens), Atka mackerel (Pleurogrammus monopterygius), and various species of seabirds during the period of the recent otter population decline. Breeding success and productivity of Bald Eagles also increased during this time period, which may be due to the higher nutritional quality of avian prey consumed in later years. Our results provide further evidence of the wide-ranging indirect effects of sea otter predation on nearshore marine communities and another apex predator, the Bald Eagle. Although the indirect effects of sea otters are widely known, this example is unique because the food-web pathway transcended five species and several trophic levels in linking one apex predator

  15. Bald eagles and sea otters in the Aleutian Archipelago: indirect effects of trophic cascades.

    PubMed

    Anthony, Robert G; Estes, James A; Ricca, Mark A; Miles, A Keith; Forsman, Eric D

    2008-10-01

    Because sea otters (Enhydra lutris) exert a wide array of direct and indirect effects on coastal marine ecosystems throughout their geographic range, we investigated the potential influence of sea otters on the ecology of Bald Eagles (Haliaeetus leucocephalus) in the Aleutian Islands, Alaska, USA. We studied the diets, productivity, and density of breeding Bald Eagles on four islands during 1993-1994 and 2000-2002, when sea otters were abundant and scarce, respectively. Bald Eagles depend on nearshore marine communities for most of their prey in this ecosystem, so we predicted that the recent decline in otter populations would have an indirect negative effect on diets and demography of Bald Eagles. Contrary to our predictions, we found no effects on density of breeding pairs on four islands from 1993-1994 to 2000-2002. In contrast, diets and diet diversity of Bald Eagles changed considerably between the two time periods, likely reflecting a change in prey availability resulting from the increase and subsequent decline in sea otter populations. The frequency of sea otter pups, rock greenling (Hexagammus lagocephalus), and smooth lumpsuckers (Aptocyclus ventricosus) in the eagle's diet declined with corresponding increases in Rock Ptarmigan (Lagopus mutus), Glaucous-winged Gulls (Larus glaucescens), Atka mackerel (Pleurogrammus monopterygius), and various species of seabirds during the period of the recent otter population decline. Breeding success and productivity of Bald Eagles also increased during this time period, which may be due to the higher nutritional quality of avian prey consumed in later years. Our results provide further evidence of the wide-ranging indirect effects of sea otter predation on nearshore marine communities and another apex predator, the Bald Eagle. Although the indirect effects of sea otters are widely known, this example is unique because the food-web pathway transcended five species and several trophic levels in linking one apex predator

  16. Bald eagles and sea otters in the Aleutian Archipelago: indirect effects of trophic cascades.

    USGS Publications Warehouse

    Anthony, R.G.; Estes, J.A.; Ricca, M.A.; Miles, A.K.; Forsman, E.D.

    2008-01-01

    Because sea otters (Enhydra lutris) exert a wide array of direct and indirect effects on coastal marine ecosystems throughout their geographic range, we investigated the potential influence of sea otters on the ecology of Bald Eagles (Haliaeetus leucocephalus) in the Aleutian Islands, Alaska, USA. We studied the diets, productivity, and density of breeding Bald Eagles on four islands during 1993-1994 and 2000-2002, when sea otters were abundant and scarce, respectively. Bald Eagles depend on nearshore marine communities for most of their prey in this ecosystem, so we predicted that the recent decline in otter populations would have an indirect negative effect on diets and demography of Bald Eagles. Contrary to our predictions, we found no effects on density of breeding pairs on four islands from 1993-1994 to 2000-2002. In contrast, diets and diet diversity of Bald Eagles changed considerably between the two time periods, likely reflecting a change in prey availability resulting from the increase and subsequent decline in sea otter populations. The frequency of sea otter pups, rock greenling (Hexagammus lagocephalus), and smooth lumpsuckers (Aptocyclus ventricosus) in the eagle's diet declined with corresponding increases in Rock Ptarmigan (Lagopus mutus), Glaucous-winged Gulls (Larus glaucescens), Atka mackerel (Pleurogrammus monopterygius), and various species of seabirds during the period of the recent otter population decline. Breeding success and productivity of Bald Eagles also increased during this time period, which may be due to the higher nutritional quality of avian prey consumed in later years. Our results provide further evidence of the wide-ranging indirect effects of sea otter predation on nearshore marine communities and another apex predator, the Bald Eagle. Although the indirect effects of sea otters are widely known, this example is unique because the food-web pathway transcended five species and several trophic levels in linking one apex predator

  17. Fishing effects on energy use by North Sea fishes

    NASA Astrophysics Data System (ADS)

    Jennings, Simon; van Hal, Ralf; Hiddink, Jan G.; Maxwell, Tracy A. D.

    Fishing affects patterns of energy use in fish populations, as demonstrated by changes in population energy consumption and the size and age when energy demands are greatest. We compare theoretical predictions and observed patterns of energy use (expressed as the primary production required to support fish production) by North Sea fish, based on simple and widely applicable theory that links life history parameters, fishing mortality ( F), trophic transfer efficiency and relationships between size and trophic level (as determined using nitrogen stable isotope analysis). For the demersal species that dominate total biomass, relationships between size and trophic level were quite consistent among years. There were large decreases in relative energy requirements of all exploited demersal populations except plaice Pleuronectes platessa during the last 3 to 4 decades. Relative energy requirements of plaice were more stable because smaller plaice, which now dominate the exploited population, feed at higher trophic levels than larger plaice. The sizes and ages when population energy demands were greatest fell with increasing fishing mortality and differences between the predicted ( F = 0) and observed ages at maximum energy demand were greater in larger species. Currently, the energy demands of most species peak early in life (1-3 years) and largely reflect patterns of recruitment, leading to a homogenisation of the trophodynamics of the fish community. The fate of energy that is no longer used by commercially exploited species is not clear, partly because of the infrequent and untargeted monitoring of species that are more resilient to fishing. However, we conducted a preliminary assessment of the energy demands of solenette Buglossidium luteum, a very abundant small flatfish in the central North Sea that has increased in abundance in recent years. The solenette's high abundance and resilience to fishing, suggests that it now requires 35% of primary production in part of

  18. Investigating Effects of Monsoon Winds on Hydrodynamics in the South China Sea

    NASA Astrophysics Data System (ADS)

    Chua, V. P.

    2013-12-01

    The South China Sea is a large marginal sea surrounded by land masses and island chains, and characterized by complex bathymetry and irregular coastlines. The circulation in South China Sea is subjected to seasonal and inter-annual variations of tidal and meteorological conditions. The effects of monsoon winds on hydrodynamics is investigated by applying spectral and harmonic analysis on surface elevation and wind data at stations located in the South China Sea. The analysis indicates varying responses to the seasonal monsoon depending on the location of the station. At Kaohsiung (located in northern South China Sea off Taiwan coast), tides from the Pacific Ocean and the southwest monsoon winds are found to be dominant mechanisms. The Kota Kinabalu and Bintulu stations, located to the east of South China Sea off Borneo coast, are influenced by low energy complex winds, and the shallow bottom bathymetry at these locations leads to tidal energy damping compared to other stations. The tidal dynamics at Tioman, located in southern South China Sea off Malaysia coast, are most responsive to the effects of the northeast monsoon. The complexity of our problem together with the limited amount of available data in the region presents a challenging research topic. An unstructured-grid SUNTANS model is employed to perform three-dimensional simulations of the circulation in South China Sea. Skill assessment of the model is performed by comparing model predictions of the surface elevations and currents with observations. The results suggest that the quality of the model prediction is highly dependent on horizontal grid resolution and coastline accuracy. The model may be used in future applications to investigate seasonal and inter-annual variations in hydrodynamics.

  19. Scale effect and optimum relations for sea surface planning

    NASA Technical Reports Server (NTRS)

    Sedov, L.

    1947-01-01

    From the general dimensional and mechanical similarity theory it follows that a condition of steady motion of a given shape\\bottom with constant speed on the surface of water is determined by four nondimensional parameters. By considering the various systems of independent parameters which are applied in theory and practice and special tests, there is determined their mutual relations and their suitability as planning characteristics. In studying the scale effect on the basis of the Prnndtl formula for the friction coefficient for a turbulent condition the order of magnitude is given of the error in applying the model data to full scale in the case of a single-step bottom For a bottom of complicated shape it is shown how from the test data of the hydrodynamic characteristics for one speed with various loads, or one load with various speeds, there may be obtained by simple computation with good approximation the hydrodynamic characteristics for a different speed or for a different load. (These considerations may be of use in solving certain problems on the stability of planning.) This permits extrapolating the curve of resistance against speed for large speeds inaccessible in the tank tests or for other loads which were not tested. The data obtained by computation are in good agreement with the test results. Problems regarding the optimum trim angle or the optimum width in the case of planning of a flat plate are considered from the point of view of the minimum resistance for a given load on the water and planning speeds. Formulas and graphs are given for the optimum value of the planning coefficient and the corresponding values of the trim angle and width of the flat plate.

  20. GIS analysis of effects of future Baltic sea level rise on the island of Gotland, Sweden

    NASA Astrophysics Data System (ADS)

    Ebert, Karin; Ekstedt, Karin; Jarsjö, Jerker

    2016-07-01

    Future sea level rise as a consequence of global warming will affect the world's coastal regions. Even though the pace of sea level rise is not clear, the consequences will be severe and global. Commonly the effects of future sea level rise are investigated for relatively vulnerable development countries; however, a whole range of varying regions needs to be considered in order to improve the understanding of global consequences. In this paper we investigate consequences of future sea level rise along the coast of the Baltic Sea island of Gotland, Sweden, with the aim to fill knowledge gaps regarding comparatively well-suited areas in developed countries. We study both the quantity of the loss of features of infrastructure, cultural, and natural value in the case of a 2 m sea level rise of the Baltic Sea and the effects of climate change on seawater intrusion in coastal aquifers, which indirectly cause saltwater intrusion in wells. We conduct a multi-criteria risk analysis by using lidar data on land elevation and GIS-vulnerability mapping, which gives the application of distance and elevation parameters formerly unimaginable precision. We find that in case of a 2 m sea level rise, 3 % of the land area of Gotland, corresponding to 99 km2, will be inundated. The features most strongly affected are items of touristic or nature value, including camping places, shore meadows, sea stack areas, and endangered plants and species habitats. In total, 231 out of 7354 wells will be directly inundated, and the number of wells in the high-risk zone for saltwater intrusion in wells will increase considerably. Some valuable features will be irreversibly lost due to, for example, inundation of sea stacks and the passing of tipping points for seawater intrusion into coastal aquifers; others might simply be moved further inland, but this requires considerable economic means and prioritization. With nature tourism being one of the main income sources of Gotland, monitoring and

  1. Antiproliferative effects of triterpenoidal derivatives, obtained from the marine sponge Siphonochalina sp., on human hepatic and colorectal cancer cells.

    PubMed

    Abdel-Lateff, Ahmed; Al-Abd, Ahmed M; Alahdal, Abdulrahman M; Alarif, Walied M; Ayyad, Seif-Eldin N; Al-Lihaibi, Sultan S; Hegazy, Mohamed E; Al Mohammadi, Ameen; Abdelghany, Tamer M; Abdel-Naim, Ashraf B; Moustafa, Mohamed A A; Banjer, Zainy M; Azhar, Ahmad S

    2016-01-01

    Three triterpenoidal derivatives [Sipholenol A (1), sipholenol L (2) and sipholenone A (3)] were isolated from the Red Sea sponge Siphonochalina sp. The structures were determined based on spectroscopic measurements (NMR, UV, IR and MS). The isolated compounds were evaluated for their cytotoxic activity against three cancer cell lines; HepG2, Caco-2 and HT-29. Moreover, the effects of these metabolites on cell cycle progression as well as cell cycle regulating proteins were assessed. Compounds 1, 2 and 3 showed moderate activity against HepG2 cells with IC(50) values of 17.18 ± 1.18, 24.01 ± 0.59 and 35.06 ± 1.10 μM, respectively. Compounds 1 and 2 exerted a considerable antiproliferative effect with IC(50) values of 4.80 ± 0.18 and 26.64 ± 0.30 μM, respectively, against Caco-2 cells. Finally, 1 and 2 exhibited antiproliferative activity against colorectal cancer cells (HT-29) with IC(50) values of 24.65 ± 0.80 and 4.48 ± 0.1 μM, respectively. Cell cycle analysis indicated that these compounds induced cell cycle arrest particularly in G0/G1 and S phases. Furthermore, the triterpenoids increased the expression of cyclin-B1, cyclin-D1 and cleaved caspase-3, as determined by immunofluorescence, indicating an important role of apoptosis in cell death induced by these compounds. PMID:26845717

  2. Mass Effects on the Nucleon Sea Structure Functions

    NASA Astrophysics Data System (ADS)

    Kim, Sun Myong

    Nucleon sea structure functions are studied using Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) equations with the massive gluon-quark splitting kernels for strange and charm quarks, the massless gluon-quark splitting kernels for up and down quarks, and the massless kernels for all other splitting parts. The SU(2)f flavor symmetry for two light quarks, ``up'' and ``down'', is assumed. Glück-Reya-Vogt (GRV) and Martin-Roberts-Stirling (MRS) sets are chosen to be the base structure functions at Q02=3 GeV2. We evolve the sea structure functions from Q02=3 GeV2 to Q2=50 GeV2 using the base structure function sets and DGLAP equations. Some (about 10%) enhancement is found in the strange quark distribution functions at low x (<0.1) in leading order of the DGLAP equations compared to results directly from those structure function sets at the value of Q2=50 GeV2. We provide the value of κ and also show the behavior of κ (x)=2s(x)/(¯ u(x)+¯ d(x)) after the evolution of structure functions.

  3. Quantifying the Effects of Predator and Prey Body Size on Sea Star Feeding Behaviors.

    PubMed

    Gooding, Rebecca A; Harley, Christopher D G

    2015-06-01

    Body size plays a crucial role in determining the strength of species interactions, population dynamics, and community structure. We measured how changes in body size affect the trophic relationship between the sea star Pisaster ochraceus and its prey, the mussel Mytilus trossulus. We tested the effects of a wide range of predator and prey sizes on sea stars' prey-size preference, feeding rate, and prey tissue consumption. We found that preferred prey size increased with sea star size. Pisaster consumption rate (mussels consumed per day) and tissue intake rate (grams of tissue consumed per day) also increased with sea star size. Pisaster consumption rate, but not tissue intake rate, decreased with increasing mussel size. Juvenile sea stars preferred the most profitable prey sizes-that is, those that maximized tissue consumed per unit handling time. When adult sea stars were offered larger, more profitable mussels, tissue intake rates (grams per day) tended to increase, although this relationship was not statistically significant. Our results indicate that the Pisaster-Mytilus interaction depends on the sizes of both predator and prey, that predation rates are sensitive to even small changes in body size, and that shifts in size distributions may affect predator energetics and prey numbers differently depending on the factors that limit tissue consumption rates.

  4. Can reduced predation offset negative effects of sea louse parasites on chum salmon?

    PubMed

    Peacock, Stephanie J; Connors, Brendan M; Krkosek, Martin; Irvine, James R; Lewis, Mark A

    2014-02-01

    The impact of parasites on hosts is invariably negative when considered in isolation, but may be complex and unexpected in nature. For example, if parasites make hosts less desirable to predators then gains from reduced predation may offset direct costs of being parasitized. We explore these ideas in the context of sea louse infestations on salmon. In Pacific Canada, sea lice can spread from farmed salmon to migrating juvenile wild salmon. Low numbers of sea lice can cause mortality of juvenile pink and chum salmon. For pink salmon, this has resulted in reduced productivity of river populations exposed to salmon farming. However, for chum salmon, we did not find an effect of sea louse infestations on productivity, despite high statistical power. Motivated by this unexpected result, we used a mathematical model to show how a parasite-induced shift in predation pressure from chum salmon to pink salmon could offset negative direct impacts of sea lice on chum salmon. This shift in predation is proposed to occur because predators show an innate preference for pink salmon prey. This preference may be more easily expressed when sea lice compromise juvenile salmon hosts, making them easier to catch. Our results indicate how the ecological context of host-parasite interactions may dampen, or even reverse, the expected impact of parasites on host populations.

  5. Can reduced predation offset negative effects of sea louse parasites on chum salmon?

    PubMed Central

    Peacock, Stephanie J.; Connors, Brendan M.; Krkošek, Martin; Irvine, James R.; Lewis, Mark A.

    2014-01-01

    The impact of parasites on hosts is invariably negative when considered in isolation, but may be complex and unexpected in nature. For example, if parasites make hosts less desirable to predators then gains from reduced predation may offset direct costs of being parasitized. We explore these ideas in the context of sea louse infestations on salmon. In Pacific Canada, sea lice can spread from farmed salmon to migrating juvenile wild salmon. Low numbers of sea lice can cause mortality of juvenile pink and chum salmon. For pink salmon, this has resulted in reduced productivity of river populations exposed to salmon farming. However, for chum salmon, we did not find an effect of sea louse infestations on productivity, despite high statistical power. Motivated by this unexpected result, we used a mathematical model to show how a parasite-induced shift in predation pressure from chum salmon to pink salmon could offset negative direct impacts of sea lice on chum salmon. This shift in predation is proposed to occur because predators show an innate preference for pink salmon prey. This preference may be more easily expressed when sea lice compromise juvenile salmon hosts, making them easier to catch. Our results indicate how the ecological context of host–parasite interactions may dampen, or even reverse, the expected impact of parasites on host populations. PMID:24352951

  6. Can reduced predation offset negative effects of sea louse parasites on chum salmon?

    PubMed

    Peacock, Stephanie J; Connors, Brendan M; Krkosek, Martin; Irvine, James R; Lewis, Mark A

    2014-02-01

    The impact of parasites on hosts is invariably negative when considered in isolation, but may be complex and unexpected in nature. For example, if parasites make hosts less desirable to predators then gains from reduced predation may offset direct costs of being parasitized. We explore these ideas in the context of sea louse infestations on salmon. In Pacific Canada, sea lice can spread from farmed salmon to migrating juvenile wild salmon. Low numbers of sea lice can cause mortality of juvenile pink and chum salmon. For pink salmon, this has resulted in reduced productivity of river populations exposed to salmon farming. However, for chum salmon, we did not find an effect of sea louse infestations on productivity, despite high statistical power. Motivated by this unexpected result, we used a mathematical model to show how a parasite-induced shift in predation pressure from chum salmon to pink salmon could offset negative direct impacts of sea lice on chum salmon. This shift in predation is proposed to occur because predators show an innate preference for pink salmon prey. This preference may be more easily expressed when sea lice compromise juvenile salmon hosts, making them easier to catch. Our results indicate how the ecological context of host-parasite interactions may dampen, or even reverse, the expected impact of parasites on host populations. PMID:24352951

  7. Long-Term Internal Variability Effects on Centennial Dynamic Sea Level Projections

    NASA Astrophysics Data System (ADS)

    Hadi Bordbar, Mohammad; Martin, Thomas; Park, Wonsun; Latif, Mojib

    2015-04-01

    The Earth's surface is warming in response to anthropogenic emissions of greenhouse gases, especially carbon dioxide (CO2). Sea level rise is one of the most pressing aspects of global warming with far-reaching consequences for coastal societies. However, sea level rise did and will strongly vary from coast to coast. Here we investigate the long-term internal variability effects on centennial projections of dynamic sea level (DSL), the local departure from the globally averaged sea level. A large ensemble of global warming integrations was conducted with a climate model, where each ensemble member was forced by identical CO2-increase but started from different atmospheric and oceanic initial conditions taken from an unforced millennial control run. In large parts of the mid- and high latitudes, the ensemble spread of the projected centennial DSL trends is of the same order of magnitude as the globally averaged steric sea level rise, suggesting internal variability cannot be ignored when assessing 21st century DSL changes. This conclusion is also supported by analyzing projections with other climate models. The ensemble spread is strongly reduced in the mid- to high latitudes if only the atmospheric initial conditions are perturbed; suggesting uncertainty in the projected centennial DSL trends there is largely due to the lack of ocean information. Thus climate model projections of regional sea level would benefit from ocean initialization.

  8. Bioaccumulation and effects of PCBs and heavy metals in sea stars (Asterias rubens, L.) from the North Sea: a small scale perspective.

    PubMed

    Danis, B; Wantier, P; Flammang, R; Pernet, Ph; Chambost-Manciet, Y; Coteur, G; Warnau, M; Dubois, Ph

    2006-03-01

    Sea stars (Asterias rubens L.) were collected in different stations distributed in the Southern Bight of the North Sea. Concentrations of four heavy metals and six PCB congeners were measured in two body compartments (body wall and pyloric caeca). In order to assess the potential harm of these contaminants, two biochemical parameters were measured in sea stars, viz. reactive oxygen species (ROS) production by amoebocytes and cytochrome P450 immunopositive protein (CYP1A IPP) induction in pyloric caeca. Sea stars from stations located in the plume of the Scheldt river showed the highest contamination levels. Other stations, similarly located, displayed lower levels. No simple relationship could be established between ROS production by sea star amoebocytes and contaminant levels measured in sea star tissues. CYP1A IPP induction displayed more contrasted responses, and highly significant regressions were found between PCB concentrations measured in pyloric caeca and CYP1A IPP. Both biological parameters were found to vary significantly over the study area. On the whole, data indicated that contamination levels and subsequent effects in sea stars were comparable to those described in previous large-scale studies, but that working at a smaller scale highlighted the existence of patterns of contamination which can blur general trends due to major contamination sources like contaminated rivers.

  9. Effects of brevetoxin exposure on the immune system of loggerhead sea turtles.

    PubMed

    Walsh, Catherine J; Leggett, Stephanie R; Carter, Barbara J; Colle, Clarence

    2010-05-10

    Blooms of the toxic dinoflagellate, Karenia brevis, occur almost annually off the Florida coast. These blooms, commonly called "red tides", produce a group of neurotoxins collectively termed brevetoxins. Many species of sealife, including sea turtles, are severely impacted by brevetoxin exposure. Effects of brevetoxins on immune cells were investigated in rescued loggerhead sea turtles, Caretta caretta, as well as through in vitro experiments using peripheral blood leukocytes (PBL) collected from captive sea turtles. In rescued animals, plasma brevetoxin concentrations were measured using a competitive ELISA. Plasma lysozyme activity was measured using a turbidity assay. Lysozyme activity correlated positively with plasma brevetoxin concentrations. Differential expression of genes affected by brevetoxin exposure was determined using two separate suppression subtractive hybridization experiments. In one experiment, genes from PBL collected from sea turtles rescued from red tide toxin exposure were compared to genes from PBL collected from healthy captive loggerhead sea turtles. In the second experiment, PBL from healthy captive loggerhead sea turtles were exposed to brevetoxin (500 ng PbTx-2/ml) in vitro for 18 h and compared to unexposed PBL. Results from the subtraction hybridization experiment conducted with red tide rescued sea turtle PBL indicated that genes involved in oxidative stress or xenobiotic metabolism were up-regulated. Using quantitative real-time PCR, a greater than 2-fold increase in superoxide dismutase and thioredoxin and greater than 10-fold increase in expression of thiopurine S-methyltransferase were observed. Results from the in vitro subtraction hybridization experiment indicated that genes coding for cytochrome c oxidases were the major up-regulated genes. Using quantitative real-time PCR, a greater than 8-fold increase in expression of beta-tubulin and greater than 3-fold increase in expression of ubiquinol were observed. Brevetoxin

  10. The Effect of Future Thermal Sea Level Changes on the Excitation of Earth Orientation Variations

    NASA Astrophysics Data System (ADS)

    Landerer, F. W.; Jungclaus, J.; Marotzke, J.

    2008-12-01

    We present a mechanism by which steric sea level rise leads to changes of the Earth's orientation parameters, e.g., polar motion (PM) and length-of-day (LOD) on decadal to centennial timescales. Steric sea level change is commonly considered unable to excite changes in Earth's orientation parameters. We show, however, that a causal link exists since thermal sea level rise leads to horizontal mass redistribution within ocean basins and hence to ocean bottom pressure changes. The projected changes of ocean angular momentum in the 21st and 22nd century are derived from simulations with the coupled climate models ECHAM5/MPI-OM and GFDL-CM2.1, forced with the IPCC-A1B emission scenario. The net effect is a mass transfer from the southern to the northern hemisphere, and also a net movement of mass closer towards Earth's axis of rotation. This, in turn, leads to a small negative LOD trend of about -0.002 ms per 10 millimeter of steric sea level rise. For polar motion, we project that ocean warming excits a movement of about 1.7 milli-arcseconds per 10 millimeter of steric sea level rise, nearly linearly polarized towards 150 degrees West. Because steric sea level rise was too small over the last 50 years, this mechanism cannot account for unexplained observed decadal fluctuations of PM and LOD during this period. However, as ocean warming and steric sea level rise are expected to accelerate in the decades to come, we conjecture that steric sea level rise could contribute increasingly more to Earth orientation variations in the near future.

  11. Loading effects in Metsähovi from the atmosphere and the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Virtanen, Heikki

    2004-10-01

    Loading by atmosphere and by the Baltic Sea cause gravity change at Metsähovi, located 15 km from the open sea. Gravity is changed by both the Newtonian attraction of the loading mass and by the crustal deformation. We have performed loading calculations using appropriate Green's function for both gravity and deformation, for both atmospheric and Baltic loading. The loading by atmosphere has been computed using a detailed surface pressure field from high resolution limited area model (HIRLAM) for north Europe up to 10° distances. Baltic Sea level is modelled using tide gauge records. Calculations show that 1 m of uniform layer of water corresponds to 31 nm s -2 in gravity and -11 mm in height. Modelled loading is compared with observations of the superconducting gravimeter T020 for years 1994-2002. The combination of HIRLAM and a tide gauge record decreases RMS of gravity residuals by 14% compared to single admittance in air pressure corrections without sea level data. Regression of gravity residuals on the tide gauge record at Helsinki (at 30 km distance) gives a gravity effect of 26 nm s -2 m -1 for Baltic loading. The gravity station is co-located with a permanent GPS station. We have also associated the loading effects of the atmosphere and of the Baltic Sea with temporal height variations. The range of modelled vertical motion due to air pressure was 46 mm and that due to sea level 18 mm. The total range was 38 mm. The effects of the Baltic Sea and of the atmosphere partly cancel each other, since at longer periods the inverse barometer assumption is valid. Regression of the modelled height on local air pressure gives -0.37 mm hPa -1, corresponding approximately to width 6° for pressure system. We have tested the models using one year of daily GPS data. Multilinear regression on local air pressure and sea level in Helsinki gives the coefficient -0.34 mm hPa -1 for pressure, and -11 mm m -1 for sea level. These match model values. Loading by air pressure and

  12. Assessment of aerosol optical property and radiative effect for the layer decoupling cases over the northern South China Sea during the 7-SEAS/Dongsha Experiment

    NASA Astrophysics Data System (ADS)

    Pani, Shantanu Kumar; Wang, Sheng-Hsiang; Lin, Neng-Huei; Tsay, Si-Chee; Lolli, Simone; Chuang, Ming-Tung; Lee, Chung-Te; Chantara, Somporn; Yu, Jin-Yi

    2016-05-01

    The aerosol radiative effect can be modulated by the vertical distribution and optical properties of aerosols, particularly when aerosol layers are decoupled. Direct aerosol radiative effects over the northern South China Sea (SCS) were assessed by incorporating an observed data set of aerosol optical properties obtained from the Seven South East Asian Studies (7-SEAS)/Dongsha Experiment into a radiative transfer model. Aerosol optical properties for a two-layer structure of aerosol transport were estimated. In the radiative transfer calculations, aerosol variability (i.e., diversity of source region, aerosol type, and vertical distribution) for the complex aerosol environment was also carefully quantified. The column-integrated aerosol optical depth (AOD) at 500 nm was 0.1-0.3 for near-surface aerosols and increased 1-5 times in presence of upper layer biomass-burning aerosols. A case study showed the strong aerosol absorption (single-scattering albedo (ω) ≈ 0.92 at 440 nm wavelength) exhibited by the upper layer when associated with predominantly biomass-burning aerosols, and the ω (≈0.95) of near-surface aerosols was greater than that of the upper layer aerosols because of the presence of mixed type aerosols. The presence of upper level aerosol transport could enhance the radiative efficiency at the surface (i.e., cooling) and lower atmosphere (i.e., heating) by up to -13.7 and +9.6 W m-2 per AOD, respectively. Such enhancement could potentially modify atmospheric stability, can influence atmospheric circulation, as well as the hydrological cycle over the tropical and low-latitude marginal northern SCS.

  13. Effects and risk evaluation of oil spillage in the sea areas of Changxing Island.

    PubMed

    Wang, Hanxi; Xu, Jianling; Zhao, Wenkui; Zhang, Jiquan

    2014-08-01

    This paper evaluated the oil spillage risk in the waters near the island of Changxing in Dalian (China) based on the established risk assessment index. Four wind regimes (windless, northerly wind, westerly wind and southerly wind) were selected as weather conditions for the dynamic prediction of oil drift. If an oil spill occurs near the Koumen (a place near the island of Changxing), the forecast and evaluation are conducted based on a three-dimensional mathematical model of oil spillage, and the results obtained show the scope of the affected area when winds from various directions are applied. The oil spillage would, under various conditions, flow into the northern and western sea area of Changxing Island Bay, namely the Dalian harbor seal National Nature Reserve, and create adverse effects on the marine ecological environment. The rationality of combining the established oil spillage risk comprehensive index system with model prediction is further confirmed. Finally, preventive measures and quick fixes are presented in the case of accidental oil spillages. The most effective method to reduce environment risk is to adopt reasonable preventive measures and quick fixes. PMID:25153473

  14. Effects and Risk Evaluation of Oil Spillage in the Sea Areas of Changxing Island

    PubMed Central

    Wang, Hanxi; Xu, Jianling; Zhao, Wenkui; Zhang, Jiquan

    2014-01-01

    This paper evaluated the oil spillage risk in the waters near the island of Changxing in Dalian (China) based on the established risk assessment index. Four wind regimes (windless, northerly wind, westerly wind and southerly wind) were selected as weather conditions for the dynamic prediction of oil drift. If an oil spill occurs near the Koumen (a place near the island of Changxing), the forecast and evaluation are conducted based on a three-dimensional mathematical model of oil spillage, and the results obtained show the scope of the affected area when winds from various directions are applied. The oil spillage would, under various conditions, flow into the northern and western sea area of Changxing Island Bay, namely the Dalian harbor seal National Nature Reserve, and create adverse effects on the marine ecological environment. The rationality of combining the established oil spillage risk comprehensive index system with model prediction is further confirmed. Finally, preventive measures and quick fixes are presented in the case of accidental oil spillages. The most effective method to reduce environment risk is to adopt reasonable preventive measures and quick fixes. PMID:25153473

  15. Modelling the increased frequency of extreme sea levels in the Ganges-Brahmaputra-Meghna delta due to sea level rise and other effects of climate change.

    PubMed

    Kay, S; Caesar, J; Wolf, J; Bricheno, L; Nicholls, R J; Saiful Islam, A K M; Haque, A; Pardaens, A; Lowe, J A

    2015-07-01

    Coastal flooding due to storm surge and high tides is a serious risk for inhabitants of the Ganges-Brahmaputra-Meghna (GBM) delta, as much of the land is close to sea level. Climate change could lead to large areas of land being subject to increased flooding, salinization and ultimate abandonment in West Bengal, India, and Bangladesh. IPCC 5th assessment modelling of sea level rise and estimates of subsidence rates from the EU IMPACT2C project suggest that sea level in the GBM delta region may rise by 0.63 to 0.88 m by 2090, with some studies suggesting this could be up to 0.5 m higher if potential substantial melting of the West Antarctic ice sheet is included. These sea level rise scenarios lead to increased frequency of high water coastal events. Any effect of climate change on the frequency and severity of storms can also have an effect on extreme sea levels. A shelf-sea model of the Bay of Bengal has been used to investigate how the combined effect of sea level rise and changes in other environmental conditions under climate change may alter the frequency of extreme sea level events for the period 1971 to 2099. The model was forced using atmospheric and oceanic boundary conditions derived from climate model projections and the future scenario increase in sea level was applied at its ocean boundary. The model results show an increased likelihood of extreme sea level events through the 21st century, with the frequency of events increasing greatly in the second half of the century: water levels that occurred at decadal time intervals under present-day model conditions occurred in most years by the middle of the 21st century and 3-15 times per year by 2100. The heights of the most extreme events tend to increase more in the first half of the century than the second. The modelled scenarios provide a case study of how sea level rise and other effects of climate change may combine to produce a greatly increased threat to life and property in the GBM delta by the end

  16. Modelling the increased frequency of extreme sea levels in the Ganges-Brahmaputra-Meghna delta due to sea level rise and other effects of climate change.

    PubMed

    Kay, S; Caesar, J; Wolf, J; Bricheno, L; Nicholls, R J; Saiful Islam, A K M; Haque, A; Pardaens, A; Lowe, J A

    2015-07-01

    Coastal flooding due to storm surge and high tides is a serious risk for inhabitants of the Ganges-Brahmaputra-Meghna (GBM) delta, as much of the land is close to sea level. Climate change could lead to large areas of land being subject to increased flooding, salinization and ultimate abandonment in West Bengal, India, and Bangladesh. IPCC 5th assessment modelling of sea level rise and estimates of subsidence rates from the EU IMPACT2C project suggest that sea level in the GBM delta region may rise by 0.63 to 0.88 m by 2090, with some studies suggesting this could be up to 0.5 m higher if potential substantial melting of the West Antarctic ice sheet is included. These sea level rise scenarios lead to increased frequency of high water coastal events. Any effect of climate change on the frequency and severity of storms can also have an effect on extreme sea levels. A shelf-sea model of the Bay of Bengal has been used to investigate how the combined effect of sea level rise and changes in other environmental conditions under climate change may alter the frequency of extreme sea level events for the period 1971 to 2099. The model was forced using atmospheric and oceanic boundary conditions derived from climate model projections and the future scenario increase in sea level was applied at its ocean boundary. The model results show an increased likelihood of extreme sea level events through the 21st century, with the frequency of events increasing greatly in the second half of the century: water levels that occurred at decadal time intervals under present-day model conditions occurred in most years by the middle of the 21st century and 3-15 times per year by 2100. The heights of the most extreme events tend to increase more in the first half of the century than the second. The modelled scenarios provide a case study of how sea level rise and other effects of climate change may combine to produce a greatly increased threat to life and property in the GBM delta by the end

  17. Cytoprotective Effects of Lysophospholipids from Sea Cucumber Holothuria atra

    PubMed Central

    Nishikawa, Yoshifumi; Furukawa, Ayumi; Shiga, Ikumi; Muroi, Yoshikage; Ishii, Toshiaki; Hongo, Yayoi; Takahashi, Shunya; Sugawara, Tatsuya; Koshino, Hiroyuki; Ohnishi, Masao

    2015-01-01

    Lysophospholipids are important signaling molecules in animals and metazoan cells. They are widely distributed among marine invertebrates, where their physiological roles are unknown. Sea cucumbers produce unique lysophospholipids. In this study, two lysophospholipids were detected in Holothuria atra for the first time, lyso-platelet activating factor and lysophosphatidylcholine, with nuclear magnetic resonance and liquid chromatography–time-of-flight mass spectrometric analyses. The lipid fraction of H. atra contained lyso-platelet activating factor and lysophosphatidylcholine, and inhibited H2O2-induced apoptosis in the macrophage cell line J774A.1. The antioxidant activity of the lysophospholipid-containing lipid fraction of H. atra was confirmed with the oxygen radical absorbance capacity method. Our results suggest that the lysophospholipids from H. atra are potential therapeutic agents for the inflammation induced by oxidative stress. PMID:26275144

  18. Effects of low-intensity pulsed electromagnetic fields on the early development of sea urchins

    SciTech Connect

    Falugi, C.; Grattarola, M.; Prestipino, G.

    1987-06-01

    The effects of weak electromagnetic signals on the early development of the sea urchin Paracentrotus lividus have been studied. The duration and repetition of the pulses were similar to those used for bone healing in clinical practice. A sequence of pulses, applied for a time ranging from 2 to 4 h, accelerates the cleavages of sea urchin embryo cells. This effect can be quantitatively assessed by determining the time shifts induced by the applied electromagnetic field on the completion of the first and second cleavages in a population of fertilized eggs. The exposed embryos were allowed to develop up to the pluteus stage, showing no abnormalities.

  19. The effect of different annealing temperatures on tin and cadmium telluride phases obtained by a modified chemical route

    SciTech Connect

    Mesquita, Anderson Fuzer; Porto, Arilza de Oliveira; Magela de Lima, Geraldo; Paniago, Roberto; Ardisson, José Domingos

    2012-11-15

    Graphical abstract: Display Omitted Highlights: ► Synthesis of cadmium and tin telluride. ► Chemical route to obtain pure crystalline cadmium and tin telluride. ► Effect of the annealing temperature on the crystalline phases. ► Removal of tin oxide as side product through thermal treatment. -- Abstract: In this work tin and cadmium telluride were prepared by a modification of a chemical route reported in the literature to obtain metallacycles formed by oxidative addition of tin-tellurium bonds to platinum (II). Through this procedure it was possible to obtain tin and cadmium telluride. X-ray diffraction and X-ray photoelectron spectroscopy were used to identify the crystalline phases obtained as well as the presence of side products. In the case of tin telluride it was identified potassium chloride, metallic tellurium and tin oxide as contaminants. The tin oxidation states were also monitored by {sup 119}Sn Mössbauer spectroscopy. The annealing in hydrogen atmosphere was chosen as a strategy to reduce the tin oxide and promote its reaction with the excess of tellurium present in the medium. The evolution of this tin oxide phase was studied through the annealing of the sample at different temperatures. Cadmium telluride was obtained with high degree of purity (98.5% relative weight fraction) according to the Rietveld refinement of X-ray diffraction data. The modified procedure showed to be very effective to obtain amorphous tin and cadmium telluride and the annealing at 450 °C has proven to be useful to reduce the amount of oxide produced as side product.

  20. Effect of primary organic sea spray emissions on cloud condensation nuclei concentrations

    NASA Astrophysics Data System (ADS)

    Westervelt, D. M.; Moore, R. H.; Nenes, A.; Adams, P. J.

    2012-01-01

    This work estimates the primary marine organic aerosol global emission source and its impact on cloud condensation nuclei (CCN) concentrations by implementing an organic sea spray source function into a series of global aerosol simulations. The source function assumes that a fraction of the sea spray emissions, depending on the local chlorophyll concentration, is organic matter in place of sea salt. Effect on CCN concentrations (at 0.2% supersaturation) is modeled using the Two-Moment Aerosol Sectional (TOMAS) microphysics algorithm coupled to the GISS II-prime general circulation model. The presence of organics affects CCN activity in competing ways: by reducing the amount of solute available in the particle and decreasing surface tension of CCN. To model surfactant effects, surface tension depression data from seawater samples taken near the Georgia coast were applied as a function of carbon concentrations. A global marine organic aerosol emission rate of 17.7 Tg C yr-1 is estimated from the simulations. Marine organics exert a localized influence on CCN(0.2%) concentrations, decreasing regional concentrations by no more than 5% and by less than 0.5% over most of the globe, assuming direct replacement of sea salt aerosol with organic aerosol. The decrease in CCN concentrations results from the fact that the decrease in particle solute concentration outweighs the organic surfactant effects. The low sensitivity of CCN(0.2%) to the marine organic emissions is likely due to the small compositional changes: the mass fraction of OA in accumulation mode aerosol increases by only ~15% in a biologically active region of the Southern Ocean. To test the sensitivity to uncertainty in the sea spray emissions process, we relax the assumption that sea spray aerosol number and mass remain fixed and instead can add to sea spray emissions rather than replace existing sea salt. In these simulations, we find that marine organic aerosol can increase CCN by up to 50% in the Southern

  1. The effects of continental growth on global sea level

    NASA Astrophysics Data System (ADS)

    Sim, S.; Stegman, D. R.; Coltice, N.

    2015-12-01

    The Earth's oceans have played an important role in the evolution of life and tectonics on Earth, and yet our understanding of basic connections between these remains limited. One of the central, and still unanswered questions, is whether Earth's oceans have been present over all of Earth's history, and how deep were any oceans that may have existed. Global tectonics provides a large influence on the long term fluctuations in sea level through varying the volume of ocean basins. The volume of ocean basins over time can be estimated from the seafloor age distribution as observed in plate reconstructions, which gives the proportion of younger, elevated seafloor to older, subsided seafloor. First we establish a relationship between sea level and the age-area distribution of oceanic crust using reconstructed oceanic plate age for recent 140 Myr from Müller et al. (2008), accounting for other major contributions such as the volume of ice sheets, the presence of large igneous provinces on the seafloor and thickness of sediments on the seafloor. We then extend this methodology back into earlier times during Earth's history by using synthetic plate reconstructions derived from numerical models of mantle convection in 3D spherical geometry. To approximate conditions for earlier in Earth's history, we consider that the Rayleigh number would have been higher in the past, resulting in faster surface velocities and, on-average, younger seafloor. Thus, we vary the surface velocity from the modern day value of 4 cm/yr to what is predicted for early Earth conditions of 80 cm/yr (corresponding to Rayleigh number of 10^8 to 10^10, respectively). Coltice et al. (2014) showed that the shape of seafloor age distribution is influenced by the growth of continental area over time, with an increasingly younger-aged, triangular shaped distribution favored for increasing continental surface. We vary the amount of continents on Earth from 0, 10%, to 30% of surface area of the Earth. These

  2. Effects of pyrolysis temperature and heating time on biochar obtained from the pyrolysis of straw and lignosulfonate.

    PubMed

    Zhang, Jie; Liu, Jia; Liu, Rongle

    2015-01-01

    In this study, the effects of pyrolysis temperature and heating time on the yield and physicochemical and morphological properties of biochar obtained from straw and lignosulfonate were investigated. As pyrolysis temperature increased, pH, ash content, carbon stability, and total content of carbon increased while biochar yield, volatile matter, total content of hydrogen, oxygen, nitrogen and sulfur decreased. The data from scanning electron microscope image and nuclear magnetic resonance spectra indicated an increase in porosity and aromaticity of biochar produced at a high temperature. The results showed that feedstock types could also influence characteristics of the biochar with absence of significant effect on properties of biochar for heating time.

  3. Effects of bioactive components of sea cucumber on the serum, liver lipid profile and lipid absorption.

    PubMed

    Hu, Xiao-Qian; Xu, Jie; Xue, Yong; Li, Zhao-Jie; Wang, Jing-Feng; Wang, Jia-Hui; Xue, Chang-Hu; Wang, Yu-Ming

    2012-01-01

    Several studies had indicated that the whole body of sea cucumber had beneficial effects on lipid metabolism. However, little information has been known on the individual functions of its bioactive components, and this study was undertaken to compare the different effects on improving lipid metabolism. The rats were assigned to seven groups: control, whole sea cucumber, saponins, polysaccharides, collagen peptides, dregs and non-saponin residues. After 28 d of feeding, the serum total cholesterol, triglyceride, high-density lipoprotein-cholesterol, and hepatic lipid concentrations were examined. The results indicated that a dietary saponin supplement significantly suppressed adipose accumulation, and reduced serum and hepatic lipids. Saponin proved to be more effective than the other isolated components, so is considered to be the main lipid-lowering component in sea cucumber. The possible mechanism by which saponins improved lipid metabolism was also investigated. The saponins of sea cucumber suppressed and delayed TG and TC absorption which could be related to the pancreatic lipase inhibiting effect of saponins. This may be an important mechanism to explain its lipid-lowering effect on rats.

  4. Effect of water temperature on sea lamprey growth and lake trout survival

    SciTech Connect

    Swink, W.D. )

    1993-11-01

    Percent mortality of lake trout Salvelinus namaycush subjected to single sea lamprey Petromyzon marinus attacks did not differ significantly between lower-temperature (mortality = 54%; temperature [le] 10[degrees]C; N = 33) and higher-temperature (mortality = 69%; temperature = 12.8-14.4[degrees]C; N = 45) laboratory studies conducted from 1 June to 28 November 1989. However, sea lampreys fed longer and killed fewer fish in colder water (mean attachment 467.0 h; 18 fish killed) than in warmer water (mean attachment 161.7 h; 31 fish killed), probably because food consumption was lower in colder water. These results indicate that the number of fish killed by sea lampreys could be much greater in warmer water and that temperature must be considered when fish losses from sea lamprey attacks are estimated. Previous studies (Swink and Hanson 1989; Swink 1990) of the effects of single sea lamprey Petromyzon marinus attacks on lake trout Salvelinus namaycush showed significantly less lake trout mortality at temperatures of 10[degrees]C and lower than at higher temperatures. The reduced host mortality, however, could not be attributed solely to lower temperature because warmwater and coldwater attacks occurred during different seasons. In those studies, the author was unable to hold water temperature at 10[degrees]C or less in late summer and early fall, when most fish are killed by sea lampreys in the Great Lakes (Christie and Kolenosky 1980; Bergstedt and Schneider 1988). Modifications to the fish holding facilities at the Hammond Bay Biological Station in 1988 allowed maintenance of a limited amount of water at 10[degrees]C or less throughout the year. Hence, the objective of this study was to compare sea lamprey-induced mortality of lake trout at 10[degrees]C or less with that at 12.8-14.4[degrees]C during the normal feeding season (June through November). 15 refs., 1 fig., 1 tab.

  5. Metallic nickel nanoparticles and their effect on the embryonic development of the sea urchin Paracentrotus lividus.

    PubMed

    Kanold, Julia Maxi; Wang, Jiabin; Brümmer, Franz; Šiller, Lidija

    2016-05-01

    The presence of nanoparticles in many industrial applications and daily products is making it nowadays crucial to assess their impact when exposed to the environment. Metallic nickel nanoparticles (Ni NPs) are of high industrial interest due to their ability to catalyze the reversible hydration of CO2 to carbonic acid at ambient conditions. We characterized metallic Ni NPs by XRD, HRTEM and EDS and determined the solubility of free nickel ions from 3 mg/L metallic Ni NPs in seawater by ICP-MS over 96 h, which was below 3%. Further, embryonic development of the sea urchin Paracentrotus lividus was investigated for 48 h in the presence of metallic Ni NPs (0.03 mg/L to 3 mg/L), but no lethal effects were observed. However, 3 mg/L metallic Ni NPs caused a size reduction similar to 1.2 mg/L NiCl2*6 H2O. The obtained results contribute to current studies on metallic Ni NPs and point to their consequences for the marine ecosystem. PMID:26849528

  6. Examining the potential for nutritional stress in young Steller sea lions: physiological effects of prey composition.

    PubMed

    Rosen, David A S; Trites, Andrew W

    2005-05-01

    The effects of high- and low-lipid prey on the body mass, body condition, and metabolic rates of young captive Steller sea lions (Eumetopias jubatus) were examined to better understand how changes in prey composition might impact the physiology and health of wild sea lions and contribute to their population decline. Results of three feeding experiments suggest that prey lipid content did not significantly affect body mass or relative body condition (lipid mass as a percent of total mass) when sea lions could consume sufficient prey to meet their energy needs. However, when energy intake was insufficient to meet daily requirements, sea lions lost more lipid mass (9.16+/-1.80 kg+/-SE) consuming low-lipid prey compared with eating high-lipid prey (6.52+/-1.65 kg). Similarly, the sea lions lost 2.7+/-0.9 kg of lipid mass while consuming oil-supplemented pollock at maintenance energy levels but gained 5.2+/-2.7 kg lipid mass while consuming identical energetic levels of herring. Contrary to expectations, there was a 9.7+/-1.8% increase in metabolism during mass loss on submaintenance diets. Relative body condition decreased only 3.7+/-3.8% during periods of imposed nutritional stress, despite a 10.4+/-4.8% decrease in body mass. These findings raise questions regarding the efficacy of measures of relative body condition to detect such changes in nutritional status among wild animals. The results of these three experiments suggest that prey composition can have additional effects on sea lion energy stores beyond the direct effects of insufficient energy intake. PMID:15900507

  7. Evidence of Season-Dependency in Vegetation Effects on Macrofauna in Temperate Seagrass Meadows (Baltic Sea)

    PubMed Central

    Włodarska-Kowalczuk, Maria; Jankowska, Emilia; Kotwicki, Lech; Balazy, Piotr

    2014-01-01

    Seagrasses and associated macrophytes are important components of coastal systems as ecosystem engineers, habitat formers, and providers of food and shelter for other organisms. The positive impacts of seagrass vegetation on zoobenthic abundance and diversity (as compared to bare sands) are well documented, but only in surveys performed in summer, which is the season of maximum canopy development. Here we present the results of the first study of the relationship between the seasonal variability of seagrass vegetation and persistence and magnitude of contrasts in faunal communities between vegetated and bare sediments. The composition, abundance, biomass, and diversity of macrozoobenthos in both habitats were compared five times throughout the year in temperate eelgrass meadows in the southern Baltic Sea. Significant positive effects of macrophyte cover on invertebrate density and biomass were recorded only in June, July, and October when the seagrass canopy was relatively well developed. The effects of vegetation cover on faunal species richness, diversity, and composition persisted throughout the year, but the magnitude of these effects varied seasonally and followed changes in macrophyte biomass. The strongest effects were observed in July and coincided with maximums in seagrass biomass and the diversity and biomass of other macrophytes. These observations indicate that in temperate, clearly seasonal systems the assessment of macrophyte impact cannot be based solely on observations performed in just one season, especially when that season is the one in which macrophyte growth is at its maximum. The widely held belief that macrophyte cover strongly influences benthic fauna in marine coastal habitats, which is based on summer surveys, should be revisited and complemented with information obtained in other seasons. PMID:25000560

  8. Evidence of season-dependency in vegetation effects on macrofauna in temperate seagrass meadows (Baltic Sea).

    PubMed

    Włodarska-Kowalczuk, Maria; Jankowska, Emilia; Kotwicki, Lech; Balazy, Piotr

    2014-01-01

    Seagrasses and associated macrophytes are important components of coastal systems as ecosystem engineers, habitat formers, and providers of food and shelter for other organisms. The positive impacts of seagrass vegetation on zoobenthic abundance and diversity (as compared to bare sands) are well documented, but only in surveys performed in summer, which is the season of maximum canopy development. Here we present the results of the first study of the relationship between the seasonal variability of seagrass vegetation and persistence and magnitude of contrasts in faunal communities between vegetated and bare sediments. The composition, abundance, biomass, and diversity of macrozoobenthos in both habitats were compared five times throughout the year in temperate eelgrass meadows in the southern Baltic Sea. Significant positive effects of macrophyte cover on invertebrate density and biomass were recorded only in June, July, and October when the seagrass canopy was relatively well developed. The effects of vegetation cover on faunal species richness, diversity, and composition persisted throughout the year, but the magnitude of these effects varied seasonally and followed changes in macrophyte biomass. The strongest effects were observed in July and coincided with maximums in seagrass biomass and the diversity and biomass of other macrophytes. These observations indicate that in temperate, clearly seasonal systems the assessment of macrophyte impact cannot be based solely on observations performed in just one season, especially when that season is the one in which macrophyte growth is at its maximum. The widely held belief that macrophyte cover strongly influences benthic fauna in marine coastal habitats, which is based on summer surveys, should be revisited and complemented with information obtained in other seasons.

  9. Response of yellowtail, Seriola quinqueradiata, a key large predatory fish in the Japan Sea, to sea water temperature over the last century and potential effects of global warming

    NASA Astrophysics Data System (ADS)

    Tian, Yongjun; Kidokoro, Hideaki; Watanabe, Tatsuro; Igeta, Yosuke; Sakaji, Hideo; Ino, Shingo

    2012-03-01

    We examined the long-term variability in the abundance of yellowtail Seriola quinqueradiata and its relationship with sea water temperature in the Japan Sea, which is one of the most rapidly warming large marine ecosystems in the world ocean. The total catch of yellowtail has ranged from 14,000 to 77,000 t with an increasing trend over the last century. Decadal-scale variability was found for yellowtail with significant shifts occurring around 1911, 1931, 1950, 1973, 1989 and 2000, which was in accordance with sea surface temperatures (SST). In particular, there was close correspondence between water temperature and catch in the Japan Sea; significant and positive correlations between SSTs and catch indicated increasing water temperature in the Tsushima Warm Current region has led to positive effects on migration and recruitment of yellowtail. SST mapping of optimum water temperature for yellowtail habitat indicated a northward extension in distribution and overwintering areas of yellowtail in the Japan Sea during the warm 1990s, suggested that the migration pattern, distribution and overwintering area are largely dictated by SST. Hence, potential impacts of global warming on migration, distribution and fisheries grounds of yellowtail in the Japan Sea were estimated based on the prediction of the IPCC A1B scenario which indicated northward extension in distribution and overwintering region with global warming and will have large impacts on the fisheries for yellowtail.

  10. Thermodynamic and functional characteristics of deep-sea enzymes revealed by pressure effects.

    PubMed

    Ohmae, Eiji; Miyashita, Yurina; Kato, Chiaki

    2013-09-01

    Hydrostatic pressure analysis is an ideal approach for studying protein dynamics and hydration. The development of full ocean depth submersibles and high pressure biological techniques allows us to investigate enzymes from deep-sea organisms at the molecular level. The aim of this review was to overview the thermodynamic and functional characteristics of deep-sea enzymes as revealed by pressure axis analysis after giving a brief introduction to the thermodynamic principles underlying the effects of pressure on the structural stability and function of enzymes.

  11. The Effect of Excess Snow on Sea Ice in a Global Ice-Ocean Prediction System

    NASA Astrophysics Data System (ADS)

    Winter, B.; Bélair, S.; Lemieux, J. F.

    2014-12-01

    Snow cover on sea ice acts as a thermal insulator, greatly reducing the upward heat flux from the ocean through the ice, specifically through thin ice. The treatment of snow in the CICE sea ice model does not include the effects of blowing snow, thereby leading to an unrealistically thick snow layer on the ice. We investigate the consequences of this excess snow for the upward heat fluxes throughout the year, and how this impacts forecast accuracy in a global ice-ocean prediction model (GIOPS). First results will be presented, and computationally efficient solutions will be discussed.

  12. Effects of protracted cadmium exposure on gametes of the purple sea urchin, Arbacia punctulata

    SciTech Connect

    Bowen, W.J. III; Engel, D.W.

    1996-03-01

    Gametes and larvae of sea urchins and more specifically Arbacia punctulata have been used extensively in embryological studies and toxicity bioassay testing. Most of the experiments and bioassays have used the fertilized eggs of different sea urchin species and measured abnormal growth, malformations, or changes in the rates of growth as a function of contaminant exposure. Guida demonstrated that cupric ion activities of <10{sup -10.5} M caused reductions in the rates of growth of Arbacia Punctulata larvae and caused incomplete or malformed pluteal skeletons. These effects occurred at cupric ion concentrations that were in the same ranges as some measured in the more contaminated estuaries in the northeastern U.S. Sunda and coworkers also used sea urchin embryonic development to test potential trace metal toxicity in water samples collected from those same estuaries, and demonstrated toxicity potentially attributable to dissolved trace metals in the water column. The purpose of these experiments was to determine if protracted sublethal exposure of sexually mature sea urchins to dissolved cadmium in sea water would affect the viability of eggs and sperm, and whether it would affect fertilization and embryonic development and ultimately the larvae. The results of the experiments support the hypothesis that spermatogenesis and oogenesis were affected by cadmium exposure.

  13. Geologic effects and coastal vulnerability to sea-level rise, erosion, and storms

    USGS Publications Warehouse

    Williams, S.J.; Gutierrez, B.T.; Thieler, E.R.; Pendleton, E.

    2008-01-01

    A combination of natural and human factors are driving coastal change and making coastal regions and populations increasingly vulnerable. Sea level, a major agent of coastal erosion, has varied greatly from -120 m below present during glacial period low-stands to + 4 to 6 m above present during interglacial warm periods. Geologic and tide gauge data show that global sea level has risen about 12 to 15 cm during the past century with satellite measurements indicating an acceleration since the early 1990s due to thermal expansion and ice-sheet melting. Land subsidence due to tectonic forces and sediment compaction in regions like the mid-Atlantic and Louisiana increase the rate of relative sea-level rise to 40 cm to 100 cm per century. Sea- level rise is predicted to accelerate significantly in the near future due to climate change, resulting in pervasive impacts to coastal regions and putting populations increasingly at risk. The full implications of climate change for coastal systems need to be understood better and long-term plans are needed to manage coasts in order to protect natural resources and mitigate the effects of sea-level rise and increased storms on human infrastructure. Copyright ASCE 2008.

  14. Effects of long-term variability on projections of twenty-first century dynamic sea level

    NASA Astrophysics Data System (ADS)

    Bordbar, Mohammad H.; Martin, Thomas; Latif, Mojib; Park, Wonsun

    2015-04-01

    Sea-level rise is one of the most pressing aspects of anthropogenic global warming with far-reaching consequences for coastal societies. However, sea-level rise did and will strongly vary from coast to coast. Here we investigate the long-term internal variability effects on centennial projections of dynamic sea level (DSL), the local departure from the globally averaged sea level. A large ensemble of global warming integrations has been conducted with a climate model, where each realization was forced by identical CO2 increase but started from different atmospheric and oceanic initial conditions. In large parts of the mid- and high latitudes, the ensemble spread of the projected centennial DSL trends is of the same order of magnitude as the globally averaged steric sea-level rise, suggesting that internal variability cannot be ignored when assessing twenty-first-century DSL trends. The ensemble spread is considerably reduced in the mid- to high latitudes when only the atmospheric initial conditions differ while keeping the oceanic initial state identical; indicating that centennial DSL projections are strongly dependent on ocean initial conditions.

  15. Effects of wildfire on sea otter (Enhydra lutris) gene transcript profiles

    USGS Publications Warehouse

    Bowen, Lizabeth; Miles, A. Keith; Kolden, Crystal A.; Saarinen, Justin A.; Bodkin, James L.; Murray, Michael J.; Tinker, M. Tim

    2015-01-01

    Wildfires have been shown to impact terrestrial species over a range of temporal scales. Little is known, however, about the more subtle toxicological effects of wildfires, particularly in downstream marine or downwind locations from the wildfire perimeter. These down-current effects may be just as substantial as those effects within the perimeter. We used gene transcription technology, a sensitive indicator of immunological perturbation, to study the effects of the 2008 Basin Complex Fire on the California coast on a sentinel marine species, the sea otter (Enhydra lutris). We captured sea otters in 2008 (3 mo after the Basin Complex Fire was controlled) and 2009 (15 mo after the Basin Complex Fire was controlled) in the adjacent nearshore environment near Big Sur, California. Gene responses were distinctly different between Big Sur temporal groups, signifying detoxification of PAHs, possible associated response to potential malignant transformation, and suppression of immune function as the primary responses of sea otters to fire in 2008 compared to those captured in 2009. In general, gene transcription patterns in the 2008 sea otters were indicative of molecular reactions to organic exposure, malignant transformation, and decreased ability to respond to pathogens that seemed to consistent with short-term hydrocarbon exposure.

  16. 34 CFR 200.84 - Responsibilities of SEAs for evaluating the effectiveness of the MEP.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 1 2012-07-01 2012-07-01 false Responsibilities of SEAs for evaluating the effectiveness of the MEP. 200.84 Section 200.84 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION TITLE I-IMPROVING...

  17. 34 CFR 200.84 - Responsibilities of SEAs for evaluating the effectiveness of the MEP.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 1 2011-07-01 2011-07-01 false Responsibilities of SEAs for evaluating the effectiveness of the MEP. 200.84 Section 200.84 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION TITLE I-IMPROVING...

  18. 34 CFR 200.84 - Responsibilities of SEAs for evaluating the effectiveness of the MEP.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 1 2014-07-01 2014-07-01 false Responsibilities of SEAs for evaluating the effectiveness of the MEP. 200.84 Section 200.84 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION TITLE I-IMPROVING...

  19. Effects of light and covering behavior on PAX6 expression in the sea urchin Strongylocentrotus intermedius.

    PubMed

    Zhao, Chong; Ji, Nanjing; Sun, Ping; Feng, Wenping; Wei, Jing; Chang, Yaqing

    2014-01-01

    We studied the diel expression pattern of PAX6 (a structural gene that is commonly involved in the eye development and photoreception of eye forming animals) and the effects of light and covering behavior on PAX6 expression in the sea urchin Strongylocentrotus intermedius. We confirmed that aphotic condition significantly reduced covering behavior in S. intermedius. The diel expression pattern of PAX6 was significantly different in S. intermedius under photic and aphotic conditions. The gene expression of PAX6 significantly deceased in covered S. intermedius both under natural light and in darkness. The present finding provides valuable insight into the probable link between covering and PAX6 expression of sea urchins. Further studies are required to investigate the detailed expression network of light detection involved genes in order to fully reveal the molecular mechanism of the light-induced covering behavior of sea urchins.

  20. Cooling rate effects on thermal, structural, and microstructural properties of bio-hydroxyapatite obtained from bovine bone.

    PubMed

    Ramirez-Gutierrez, Cristian F; Palechor-Ocampo, Anderzon F; Londoño-Restrepo, Sandra M; Millán-Malo, Beatriz M; Rodriguez-García, Mario E

    2016-02-01

    This article is focused on the study of cooling rate effects on the thermal, structural, and microstructural properties of hydroxyapatite (HAp) obtained from bovine bone. A three-step process was used to obtain BIO-HAp: hydrothermal, calcinations, and cooling. Calcined samples in a furnace and cooling in air (HAp-CAir), water (HAp-CW), and liquid nitrogen (HAp-CN2), as well as an air cooled sample inside the furnace (HAp-CFAir), were studied. According to this study, the low cooling rate that was achieved for air cooled samples inside the furnace produce single crystal BIO-HAp with better crystalline quality; other samples exhibited polycrystalline structures forming micron and submicron grains. PMID:25952013

  1. Effect of initial phase on error in electron energy obtained using paraxial approximation for a focused laser pulse in vacuum

    SciTech Connect

    Singh, Kunwar Pal; Arya, Rashmi; Malik, Anil K.

    2015-09-14

    We have investigated the effect of initial phase on error in electron energy obtained using paraxial approximation to study electron acceleration by a focused laser pulse in vacuum using a three dimensional test-particle simulation code. The error is obtained by comparing the energy of the electron for paraxial approximation and seventh-order correction description of the fields of Gaussian laser. The paraxial approximation predicts wrong laser divergence and wrong electron escape time from the pulse which leads to prediction of higher energy. The error shows strong phase dependence for the electrons lying along the axis of the laser for linearly polarized laser pulse. The relative error may be significant for some specific values of initial phase even at moderate values of laser spot sizes. The error does not show initial phase dependence for a circularly laser pulse.

  2. Cooling rate effects on thermal, structural, and microstructural properties of bio-hydroxyapatite obtained from bovine bone.

    PubMed

    Ramirez-Gutierrez, Cristian F; Palechor-Ocampo, Anderzon F; Londoño-Restrepo, Sandra M; Millán-Malo, Beatriz M; Rodriguez-García, Mario E

    2016-02-01

    This article is focused on the study of cooling rate effects on the thermal, structural, and microstructural properties of hydroxyapatite (HAp) obtained from bovine bone. A three-step process was used to obtain BIO-HAp: hydrothermal, calcinations, and cooling. Calcined samples in a furnace and cooling in air (HAp-CAir), water (HAp-CW), and liquid nitrogen (HAp-CN2), as well as an air cooled sample inside the furnace (HAp-CFAir), were studied. According to this study, the low cooling rate that was achieved for air cooled samples inside the furnace produce single crystal BIO-HAp with better crystalline quality; other samples exhibited polycrystalline structures forming micron and submicron grains.

  3. Mobile multimedia antenna systems for station wagons and the achievable diversity effectiveness obtained by analysis of virtual test drives

    NASA Astrophysics Data System (ADS)

    Hopf, J. F.; Lindenmeier, H. K.; Reiter, L. M.

    2003-04-01

    For modern cars, antennas are required for AM reception, FM and TV diversity reception, weatherband reception (USA), terrestrial digital radio, remote control functions, keyless entry, mobile phone for all worldwide used systems, GPS, and in the future, satellite broadcast radio services. Those services cover the frequency range from 150 kHz up to 2.4 GHz. Such kind of a multiantenna system developed for station wagons is presented in this paper. The obtainable FM and TV diversity effectiveness is discussed for several types of antenna arrangements in detail. This value is the number of fictitious completely decorrelated antenna signals and is obtained by virtual test drives. The characteristic of the respective antennas under test is introduced in the software as antenna pattern, measured or calculated with respect to amplitude and phase. During the computer analysis the car with the antennas is driven virtually through a Rayleigh field scenario with desired and undesired signals.

  4. Impacts of wind forcing on sea level variations in the East China Sea: Local and remote effects

    NASA Astrophysics Data System (ADS)

    Li, Yanfang; Zuo, Juncheng; Lu, Qing; Zhang, Hua; Chen, Meixiang

    2016-02-01

    The regional sea level variation in the East China Sea (ECS) was influenced not only by local factors but also by remote wind from adjoining ocean with the oceanic connectivity influenced by upper-ocean circulation. The satellite altimeter observations showed that from 1993 to 2008, the inter-annual sea level variation in the ECS was negatively related to the strength of Kuroshio. To investigate the relative role of local and remote wind, two sensitive experiments were carried out using the POP model. Model experiments revealed that wind-induced redistributions of water played a significant role in the sea level variation of the ECS. The seasonal variations were induced by both local winds and remote Pacific wind stress with approximately equal contribution. However, on the inter-annual sea level variations, the remote wind forcing over the North Pacific could contribute substantially more than that of local wind which modulated sea level immediately. Remote wind influenced the China Sea in forms of changing of wind stress curl and ocean currents, which influenced the intensity of the Kuroshio, especially during El Nino episodes.

  5. Effects of sea-level rise on ground water flow in a coastal aquifer system

    USGS Publications Warehouse

    Masterson, J.P.; Garabedian, S.P.

    2007-01-01

    The effects of sea-level rise on the depth to the fresh water/salt water interface were simulated by using a density-dependent, three-dimensional numerical ground water flow model for a simplified hypothetical fresh water lens that is similar to shallow, coastal aquifers found along the Atlantic coast of the United States. Simulations of sea-level rise of 2.65 mm/year from 1929 to 2050 resulted in an increase in water levels relative to a fixed datum, yet a net decrease in water levels relative to the increased sea-level position. The net decrease in water levels was much greater near a gaining stream than farther from the stream. The difference in the change in water levels is attributed to the dampening effect of the stream on water level changes in response to sea-level rise. In response to the decreased water level altitudes relative to local sea level, the depth to the fresh water/salt water interface decreased. This reduction in the thickness of the fresh water lens varied throughout the aquifer and was greatly affected by proximity to a ground water fed stream and whether the stream was tidally influenced. Away from the stream, the thickness of the fresh water lens decreased by about 2% from 1929 to 2050, whereas the fresh water lens thickness decreased by about 22% to 31% for the same period near the stream, depending on whether the stream was tidally influenced. The difference in the change in the fresh water/salt water interface position is controlled by the difference in the net decline in water levels relative to local sea level. ?? 2007 National Ground Water Association.

  6. Effects of North Sea oil and alkylphenols on biomarker responses in juvenile Atlantic cod (Gadus morhua).

    PubMed

    Sturve, Joachim; Hasselberg, Linda; Fälth, Herman; Celander, Malin; Förlin, Lars

    2006-06-01

    A consequence of oil drilling at sea is the release of produced water contaminated with e.g. polycyclic aromatic hydrocarbons (PAH) and alkylphenols. In the present study, juvenile Atlantic cod were exposed to North Sea oil, nonylphenol and a combination of the North Sea oil and an alkylphenol mixture in a flow-through system. A suite of hepatic biomarkers were analysed. Exposure to North Sea oil resulted in strong induction of CYP1A protein levels and EROD activities. Exposure to nonylphenol, on the other hand, resulted in decreased CYP1A levels and EROD activities. Thus, nonylphenol appears to down-regulate CYP1A expression in Atlantic cod. Combined exposure to North Sea oil with an alkylphenol mixture resulted in lower EROD induction, compared to that in fish exposed to North Sea oil alone. This difference was not statistically significant, but still we believe that the alkylphenols have inhibited CYP1A activities in the fish which may have compromised CYP1A mediated metabolism of other xenobiotics, including PAH. CYP3A protein levels were lower, compared to controls, in fish exposed to nonylphenol and the combination of North Sea oil and alkylphenol mixture. In contrast, the oil alone had no effect on CYP3A protein content. North Sea oil exposure, alone or in combination with alkylphenols, caused oxidative stress observed as elevated levels of GSSG content and GR and CAT activities. Interestingly, exposure to nonylphenol resulted in a marked depletion of total glutathione levels. This apparent depletion may be a consequence of increased conjugation of glutathione to nonylphenol followed by excretion. An increase in conjugation enzyme GST activity was observed in the nonylphenol exposed group, although the difference was not significant. No sign of oxidative damage, measured as lipid peroxidation, was observed in any of the exposures experiments. This study suggests that North Sea oil may lead to oxidative stress and altered CYP1A and CYP3A expression

  7. Effects of Manisa propolis on telomerase activity in leukemia cells obtained from the bone marrow of leukemia patients.

    PubMed

    Cogulu, O; Biray, C; Gunduz, C; Karaca, E; Aksoylar, S; Sorkun, K; Salih, B; Ozkinay, F

    2009-11-01

    Propolis is a resinous material collected by honeybees and obtained from beehives that has anticancer effects by inducing apoptosis. The aim of this study is to investigate the effect of propolis on human telomerase reverse transcriptase (hTERT) in the leukemia cells obtained from leukemia patients. Four different bone marrow cell cultures from each of four leukemia cases were prepared. The 60 ng/ml, 30 ng/ml and 15 ng/ml working concentrations of propolis were administered to three cultures of each patient, while one culture contained only culture medium. hTERT mRNA expression levels of cells were detected at 24 h, 48 h and 72 h using the LightCycler 2.0 instrument. A significant decrease in hTERT expression levels was observed in the 60 ng/ml concentration of propolis. In conclusion, Manisa propolis may also have a potential effect on the expression of hTERT in leukemia-particularly owing to its constituent chrysin.

  8. Incorporating Infrastructure and Vegetation Effects on Sea Level Rise Predictions in Low-Gradient Coastal Landscapes

    NASA Astrophysics Data System (ADS)

    Rodriguez, J. F.; Sandi Rojas, S.; Trivisonno, F.; Saco, P. M.; Riccardi, G.

    2015-12-01

    At the regional and global scales, coastal management and planning for future sea level rise scenarios is typically supported by modelling tools that predict the expected inundation extent. These tools rely on a number of simplifying assumptions that, in some cases, may result in important overestimation or underestimation of the inundation extent. One of such cases is coastal wetlands, where vegetation strongly affects both the magnitude and the timing of inundation. Many coastal wetlands display other forms of flow restrictions due to, for example, infrastructure or drainage works, which also alters the inundation patterns. In this contribution we explore the effects of flow restrictions on inundation patterns under sea level rise conditions in coastal wetlands. We use a dynamic wetland evolution model that not only incorporates the effects of flow restrictions due to culverts, bridges and weirs as well as vegetation, but also considers that vegetation changes as a consequence of increasing inundation. We apply our model to a coastal wetland in Australia and compare predictions of our model to predictions using conventional approaches. We found that some restrictions accentuate detrimental effects of sea level rise while others moderate them. We also found that some management strategies based on flow redistribution that provide short term solution may result more damaging in the long term if sea level rise is considered.

  9. The Potential Effect of Sea Level Rise on Coastal Property Values

    NASA Astrophysics Data System (ADS)

    O'Donnell, J.

    2015-12-01

    It is well established that one consequence of increasing global sea level is that the frequency of flooding at low-lying coastal sites will increase. We review recent evidence that the effects coastal geometry will create substantial spatial variations in the changes in flooding frequency with scales of order 100km. Using a simple model of the evolution of coastal property values we demonstrate that a consequence of sea level rise is that the appreciation of coastal properties will peak, and then decline relative to higher properties. The time when the value reach a maximum is shown to depend upon the demand for the coastal property, and the local rate of change of flooding frequency due to sea level rise. The simple model is then extended to include, in an elementary manner, the effects on the value of adjacent but higher properties. We show that the effect of increased flooding frequency of the lower properties leads to an accelerated appreciation of the value of upland properties and an accelerated decline in the value of the coastal properties. We then provide some example calculations for selected sites. We conclude with a discussion of comparisons of the prediction of the analyses to recent data, and then comments on the impact of sea level rise on tax base of coastal communities.

  10. Parental Effect of Long Acclimatization on Thermal Tolerance of Juvenile Sea Cucumber Apostichopus japonicus.

    PubMed

    Wang, Qing-Lin; Yu, Shan-Shan; Dong, Yun-Wei

    2015-01-01

    To evaluate the thermal resistance of marine invertebrates to elevated temperatures under scenarios of future climate change, it is crucial to understand parental effect of long acclimatization on thermal tolerance of offspring. To test whether there is parental effect of long acclimatization, adult sea cucumbers (Apostichopus japonicus) from the same broodstock were transplanted southward and acclimatized at high temperature in field mesocosms. Four groups of juvenile sea cucumbers whose parents experienced different durations of high temperature acclimatization were established. Upper thermal limits, oxygen consumption and levels of heat shock protein mRNA of juveniles was determined to compare thermal tolerance of individuals from different groups. Juvenile sea cucumbers whose parents experienced high temperature could acquire high thermal resistance. With the increase of parental exposure duration to high temperature, offspring became less sensitive to high temperature, as indicated by higher upper thermal limits (LT50), less seasonal variations of oxygen consumption, and stable oxygen consumption rates between chronic and acute thermal stress. The relatively high levels of constitutive expression of heat-shock proteins should contribute to the high thermal tolerance. Together, these results indicated that the existence of a parental effect of long acclimatization would increase thermal tolerance of juveniles and change the thermal sensitivity of sea cucumber to future climate change.

  11. Parental Effect of Long Acclimatization on Thermal Tolerance of Juvenile Sea Cucumber Apostichopus japonicus.

    PubMed

    Wang, Qing-Lin; Yu, Shan-Shan; Dong, Yun-Wei

    2015-01-01

    To evaluate the thermal resistance of marine invertebrates to elevated temperatures under scenarios of future climate change, it is crucial to understand parental effect of long acclimatization on thermal tolerance of offspring. To test whether there is parental effect of long acclimatization, adult sea cucumbers (Apostichopus japonicus) from the same broodstock were transplanted southward and acclimatized at high temperature in field mesocosms. Four groups of juvenile sea cucumbers whose parents experienced different durations of high temperature acclimatization were established. Upper thermal limits, oxygen consumption and levels of heat shock protein mRNA of juveniles was determined to compare thermal tolerance of individuals from different groups. Juvenile sea cucumbers whose parents experienced high temperature could acquire high thermal resistance. With the increase of parental exposure duration to high temperature, offspring became less sensitive to high temperature, as indicated by higher upper thermal limits (LT50), less seasonal variations of oxygen consumption, and stable oxygen consumption rates between chronic and acute thermal stress. The relatively high levels of constitutive expression of heat-shock proteins should contribute to the high thermal tolerance. Together, these results indicated that the existence of a parental effect of long acclimatization would increase thermal tolerance of juveniles and change the thermal sensitivity of sea cucumber to future climate change. PMID:26580550

  12. Parental Effect of Long Acclimatization on Thermal Tolerance of Juvenile Sea Cucumber Apostichopus japonicus

    PubMed Central

    Dong, Yun-wei

    2015-01-01

    To evaluate the thermal resistance of marine invertebrates to elevated temperatures under scenarios of future climate change, it is crucial to understand parental effect of long acclimatization on thermal tolerance of offspring. To test whether there is parental effect of long acclimatization, adult sea cucumbers (Apostichopus japonicus) from the same broodstock were transplanted southward and acclimatized at high temperature in field mesocosms. Four groups of juvenile sea cucumbers whose parents experienced different durations of high temperature acclimatization were established. Upper thermal limits, oxygen consumption and levels of heat shock protein mRNA of juveniles was determined to compare thermal tolerance of individuals from different groups. Juvenile sea cucumbers whose parents experienced high temperature could acquire high thermal resistance. With the increase of parental exposure duration to high temperature, offspring became less sensitive to high temperature, as indicated by higher upper thermal limits (LT50), less seasonal variations of oxygen consumption, and stable oxygen consumption rates between chronic and acute thermal stress. The relatively high levels of constitutive expression of heat-shock proteins should contribute to the high thermal tolerance. Together, these results indicated that the existence of a parental effect of long acclimatization would increase thermal tolerance of juveniles and change the thermal sensitivity of sea cucumber to future climate change. PMID:26580550

  13. Effects of artificial sea film slick upon the atmospheric boundary layer structure

    NASA Astrophysics Data System (ADS)

    Repina, Irina; Artamonov, Arseniy; Malinovsky, Vladimir; Chechin, Dmitriy

    2010-05-01

    Organic surface-active compounds accumulate at the ocean-atmosphere boundary, influencing several air-sea interaction processes. In coastal areas with high biological activity this accumulation frequently becomes visible as mirrorlike patches ("slicks") on the sea surface. The artificial surface films of oleyl alcohol and vegetable oil were produced in the Black Sea coastal zone (one site was located near Gelendjik and another was near Crimea coast) to investigate its influence on energy and gas exchange between atmosphere and sea surface under different meteorological conditions. The atmospheric turbulence measurements during the passage of an artificial sea slick are compared with similar measurements without a sea slick. The effects of the slick are modifications of roughness length z0, and a possible increase in mean wind speed. In the mean, during the passage of the slick, the roughness length decreased while the mean wind speed appeared to increase. For the spectral comparison we compared the wind field over the sea during the time the film slick was in the vicinity of the measurement site with the wind field observed after the slick had passed. The cross-spectral density was computed between horizontal velocity and vertical velocity (Reynolds stress) and between atmospheric temperature and vertical velocity (heat flux). The introduction of the sea film slick, with its damping and suppression of capillary waves, appears to completely destroy the atmospheric turbulence generation. When a slick is present, the U-W phase angle and Reynolds stress spectrum for the atmosphere appear to be completely unaffected by undulating sea surface directly below the sensors. Spectral and wavelet analysis of the atmospheric surface layer characteristics showed a significant correlation between the processes on the sea surface and the atmospheric boundary layer. An intensification of change processes in the vicinity of the windward slick boundary are detected. It may be

  14. Genotoxic and developmental effects in sea urchins are sensitive indicators of effects of genotoxic chemicals

    SciTech Connect

    Anderson, S.L. . Energy and Environment Division); Hose, J.E. . Dept. of Biology); Knezovich, J.P. . Health and Ecological Assessment Division)

    1994-07-01

    Purple sea urchin (Strongylocentrotus purpuratus) gametes and embryos were exposed to three known mutagenic chemicals (phenol, benzidine,and pentachlorophenol) over concentration ranges bracketing the effect levels for fertilization success. Normal development and cytogenetic effects (anaphase aberrations) were assessed after the cultures were allowed to develop for 48 h. Using radiolabeled chemicals, the authors also characterized concentrations in the test water as well as doses in the embryos following 2- and 48-h exposures. The authors observed dose responses for all chemicals and all responses, except for phenol, which showed no significant effect on development. Fertilization success was never the most sensitive end point. anaphase aberrations were the most sensitive response for phenol, with an LOEC of 2.5 mg/L exposure concentration. Anaphase aberrations and development were equivalent in sensitivity for benzidine within the tested dose range, and an LOEC of <0.1 mg/L was observed. Development was the most sensitive reasons for pentachlorophenol (LOEC 1 mg/L). the LOEC values for this study were generally lower than comparable data for aquatic life or human health protection. The authors conclude that genotoxicity and development evaluations should be included in environmental management applications and that tests developed primarily for human health protection do not reliably predict the effects of toxic substances on aquatic life.

  15. Barometric effects on tabular iceberg drift in the Ross Sea, Antarctica

    NASA Astrophysics Data System (ADS)

    Turnbull, Ian D.

    The Inverse Barometer Effect (IBE) was observed in the nineteenth century by Sir James Clark Ross (Ross, 1854a), as deviations in sea-surface elevation in response to deviations in atmospheric pressure. This effect embodies the inverse relationship between sea-surface height (relative to long-term mean sea level) and atmospheric surface pressure. This thesis addresses the hypothesis that icebergs in the Ross Sea region of Antarctica are influenced by the same forces that create the IBE. This hypothesis is motivated by studies of icebergs in the Ross Sea, where drift data suggest that icebergs are drawn into temporary holding zones, or "Iceberg Parking Lots" situated where the surface pressure tends to display persistent, annual average low pressure. A physical explanation for the IBE's influence on icebergs is that they are often able to travel up the sea-surface slope induced by the IBE below atmospheric lows against the gravitational pull because of the pressure gradient force of the atmosphere acting on the iceberg's freeboard (the part of the iceberg that is above the waterline). Here, I evaluate the validity of the hypothesized IBE-iceberg relationship using a combined approach of data analysis and modeling. I have examined atmospheric surface pressure and wind records taken directly from the surfaces of four Ross Sea icebergs---B15A, B15K, C16, and B15J, and I have also built, and experimented with, models that predict iceberg drift response to atmospheric surface pressure and surface winds, using observed pressures and winds from B15A and B15J as model forcing. I additionally performed various experiments on a large, idealized tabular iceberg's physical sensitivity to the IBE using a model that treats atmospheric pressure and winds in an idealized, theoretical manner. I discovered that the IBE is indeed a significant influence on iceberg drift in and around Lewis Bay, just to the north of Ross Island, which will further our understanding of these icebergs

  16. Effects of neotectonic and sedimentary processes on the seafloor geomorphology of the Tekirdag Basin of the western Marmara Sea (Turkey)

    NASA Astrophysics Data System (ADS)

    Ergin, Mustafa; Yigit-Faridfathi, Füsun

    2010-05-01

    This study forms part of a project (TUBITAK YDABCAG 101Y071) with the main purpose of investigation of late Quaternary slope stability, sediment mass movements and turbidite formations in the tectonically active Tekirdag Basin and its margins from the western Marmara Sea. The results were also intended to relate to the major earthquakes and sea-level changes. During this project, in 2001 aboard the former R/V MTA Sismik-1, a total of 100 km seismic reflection profiles were obtained along three tracklines representing from shelf to slope to deep basin environments. A multichannel airgun seismic system and well-known methods and principles of seismic stratigraphy was used for interpretations. At 11 sites from 29 to 1111 m water depths gravity sediment cores were taken having 100 to 359 cm recoveries and textural and structural characteristics were determined using standard petrographic methods. The NEE-SWW directed seismic profile (TKD-01) which runs parallel to the North Anatolian Fault zone displayed syntectonic sedimentation with negative flower structure that increased in thickness toward the Ganos Fault and pinched out in the east. ENE section of this profile also bears structures of underwater landslides with slump facies. Seismic profile TKD-02 which crosses the Tekirdag Basin in WNW-ESE direction most likely displays major 3 fault segments of the NAF zone. Many faults and syntectonic sedimentation structure can be recognized on this profile. A morphological feature of a sediment wedge or former lowstand delta at the present shelf edge can be related to the effects of last sea-level change. Mounded and chaotic seismic reflection configurations which indicate channel and slope-front fill as well as slump facies are thought to reflect submarine slides and slumps. Other morphological features such as incised submarine valleys or channels running E-W direction are also present on this profile. The seismic profile (TKD-03) runs from NNW to SSE across the basin and

  17. Effects of sea level rise on deltaic coastal marshlands, Mississippi River deltaic plain

    SciTech Connect

    Ramsey, K.E.; Penland, S. ); Roberts, H.H.; Coleman, J.M. )

    1990-05-01

    Low-relief deltaic coastal plains commonly experience land loss because of the cumulative effects of natural and human-induced processes. Although it is difficult to separate the individual factors within the overall process, interplay between these factors can result in a rate of relative sea level rise greater than the natural rate of coastal-plain aggradation that causes land loss. Between 1956 and 1978, about 11,400 and 2,490 ha of marsh were lost in east Texas and Mississippi, respectively. Louisiana's loss was 18,755 ha. Relative sea level rise over the last 65 yr has averaged 0.23 cm/yr in the Gulf and as much as 1-1.5 cm/yr in the delta plain. The Environmental Protection Agency predicts the rate of sea level rise to increase over the next century. Rates of relative sea level rise for the Gulf of Mexico are expected to increase from 0.23-1.5 cm/yr to 0.6-3.7 cm/yr. The current rate of relative sea level rise and land loss in the subsiding Mississippi delta is a response that can be expected for many US coastal areas over the next century. With the predicted change, the Mississippi River delta complex will experience dramatically increased rates of land loss. Isles Dernieres will disappear by the year 2000, and Plaquemines and Terrebonne marshes will be gone between 2020 and 2080. Based on the lowest predicted sea level rise rate, by the year 2100, the delta plain could be reduced from 150.9 {times} 10{sup 3} ha to 29.8 x 10{sup 3} ha or to 4.9 {times} 10{sup 3} ha if calculations are based on the highest rate.

  18. The effects of changing winds and temperatures on the oceanography of the Ross Sea in the 21st century

    NASA Astrophysics Data System (ADS)

    Smith, Walker O.; Dinniman, Michael S.; Hofmann, Eileen E.; Klinck, John M.

    2014-03-01

    The Ross Sea is critically important in regulating Antarctic sea ice and is biologically productive, which makes changes in the region's physical environment of global concern. We examined the effects of projected changes in atmospheric temperatures and winds on aspects of the ocean circulation likely important to primary production using a high-resolution sea ice-ocean-ice shelf model of the Ross Sea. The modeled summer sea-ice concentrations decreased by 56% by 2050 and 78% by 2100. The duration of shallow mixed layers over the continental shelf increased by 8.5 and 19.2 days in 2050 and 2100, and the mean summer mixed layer depths decreased by 12 and 44%. These results suggest that the annual phytoplankton production in the future will increase and become more diatomaceous. Other components of the Ross Sea food web will likely be severely disrupted, creating significant but unpredictable impacts on the ocean's most pristine ecosystem.

  19. Effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies

    NASA Astrophysics Data System (ADS)

    Murase, Kenya; Nanjo, Takafumi; Satoshi, Ii; Miyazaki, Shohei; Hirata, Masaaki; Sugawara, Yoshifumi; Kudo, Masayuki; Sasaki, Kousuke; Mochizuki, Teruhito

    2005-11-01

    The purpose of this study was to investigate the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using multi-detector row CT (MDCT). Following the standard CT perfusion study protocol, continuous (cine) scans (1 s/rotation × 60 s) consisting of four 5 mm thick contiguous slices were performed using an MDCT scanner with a tube voltage of 80 kVp and a tube current of 200 mA. We generated the simulated images with tube currents of 50 mA, 100 mA and 150 mA by adding the corresponding noise to the raw scan data of the original image acquired above using a noise simulation tool. From the original and simulated images, we generated the functional images of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in seven patients with cerebrovascular disease, and compared the correlation coefficients (CCs) between the perfusion parameter values obtained from the original and simulated images. The coefficients of variation (CVs) in the white matter were also compared. The CC values deteriorated with decreasing tube current. There was a significant difference between 50 mA and 100 mA for all perfusion parameters. The CV values increased with decreasing tube current. There were significant differences between 50 mA and 100 mA and between 100 mA and 150 mA for CBF. For CBV and MTT, there was also a significant difference between 150 mA and 200 mA. This study will be useful for understanding the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using MDCT, and for selecting the tube current.

  20. Leaf area index retrieval using gap fractions obtained from high resolution satellite data: Comparisons of approaches, scales and atmospheric effects

    NASA Astrophysics Data System (ADS)

    Gonsamo, Alemu

    2010-08-01

    This study is aimed at demonstrating the feasibility of the large scale LAI inversion algorithms using red and near infrared reflectance obtained from high resolution satellite imagery. Radiances in digital counts were obtained in 10 m resolution acquired on cloud free day of August 23, 2007, by the SPOT 5 high resolution geometric (HRG) instrument on mostly temperate hardwood forest located in the Great Lakes - St. Lawrence forest in Southern Quebec. Normalized difference vegetation index (NDVI), scaled difference vegetation index (SDVI) and modified soil-adjusted vegetation index (MSAVI) were applied to calculate gap fractions. LAI was inverted from the gap fraction using the common Beer-Lambert's law of light extinction under forest canopy. The robustness of the algorithm was evaluated using the ground-based LAI measurements and by applying the methods for the independently simulated reflectance data using PROSPECT + SAIL coupled radiative transfer models. Furthermore, the high resolution LAI was compared with MODIS LAI product. The effects of atmospheric corrections and scales were investigated for all of the LAI retrieval methods. NDVI was found to be not suitable index for large scale LAI inversion due to the sensitivity to scale and atmospheric effects. SDVI was virtually scale and atmospheric correction invariant. MSAVI was also scale invariant. Considering all sensitivity analysis, MSAVI performed best followed by SDVI for robust LAI inversion from high resolution imagery.

  1. Testing the Assumption of a Static Sea Level Response to Self-Attraction and Loading Effects

    NASA Astrophysics Data System (ADS)

    Vinogradova, N. T.; Ponte, R. M.; Quinn, K. J.; Tamisiea, M. E.; Davis, J. L.; Hill, E. M.

    2012-12-01

    Understanding of the ocean response to surface loading is essential to interpret observations of sea level. Such loading can be related, for example, to barometric pressure, surface mass exchange due to precipitation and evaporation, gravitational tide potential or changes in gravity field caused by non-uniform distribution of mass within the land-atmosphere-ocean system --- an effect that is often referred to as self-attraction and loading (SAL). Recent studies highlighted the importance of SAL to the understanding of the variability of sea level and ocean mass on monthly and longer time scales. The SAL-induced adjustments, however, are typically derived under the assumption that the effects give rise to a static ocean response, for which the applied loading is balanced by adjustments in the sea-level gradients. To test the static assumption, we use a global ocean model and examine the sea level response caused by SAL-induced perturbations in surface loading on monthly and longer time scales, associated with mass redistribution due to land hydrology and atmospheric and oceanic circulations. Typical standard deviations of the dynamic response (i.e., departures of sea-level from equilibrium response) are below 1 mm, which is about 10% of loading signal, suggesting that overall static assumption is valid over most of the oceans, as long as one is focused on long time scales. A few exceptions are shallow Arctic and other coastal regions, and the Southern Ocean, where deviations can exceed 30% of the surface loading and reach 2 mm. To test the equilibrium assumption at shorter (sub-monthly) time scales, we estimate the response to high-frequency (hourly) SAL load due to ocean circulation effects. In this case, for simplicity the SAL perturbations are assumed to be simply proportional to the estimated oceanic mass anomalies. Preliminary analyses point to more important dynamic signals at these high frequencies and emphasize the need for explicit inclusion of the missing

  2. Effects of sea surface warming on marine plankton.

    PubMed

    Lewandowska, Aleksandra M; Boyce, Daniel G; Hofmann, Matthias; Matthiessen, Birte; Sommer, Ulrich; Worm, Boris

    2014-05-01

    Ocean warming has been implicated in the observed decline of oceanic phytoplankton biomass. Some studies suggest a physical pathway of warming via stratification and nutrient flux, and others a biological effect on plankton metabolic rates; yet the relative strength and possible interaction of these mechanisms remains unknown. Here, we implement projections from a global circulation model in a mesocosm experiment to examine both mechanisms in a multi-trophic plankton community. Warming treatments had positive direct effects on phytoplankton biomass, but these were overcompensated by the negative effects of decreased nutrient flux. Zooplankton switched from phytoplankton to grazing on ciliates. These results contrast with previous experiments under nutrient-replete conditions, where warming indirectly reduced phytoplankton biomass via increased zooplankton grazing. We conclude that the effect of ocean warming on marine plankton depends on the nutrient regime, and provide a mechanistic basis for understanding global change in marine ecosystems.

  3. Moderate protective effect of 6-MFA, a microbial metabolite obtained from Aspergillus ochraceus on immunological liver injury in mice.

    PubMed

    Dhuley, J N; Naik, S R

    1999-01-01

    Hepatoprotective effect of 6-MFA, obtained from fungus Aspergillus ochraceus ATCC 28706, was evaluated by employing three different immunological liver injury mice models. The first liver injury model was induced by injecting anti-basic liver protein (BLP) antibody into mice previously immunised with rabbit IgG (RGG). The other models were simulated by injecting antiliver specific protein (LSP) antibody or by injecting bacterial lipopolysaccharide (LPS) into mice pretreated with Corynebacterium parvum (C. parvum). 6-MFA treatment inhibited the increased transaminases (GOT and GPT) activities and showed a tendency to inhibit the histopathological changes of the liver in all the models studied. Furthermore, 6-MFA treatment inhibited deoxycholic acid induced transaminase release from cultured rat hepatocytes in vitro, but failed to affect the formation of hemolytic plaque forming cells in immunised mice spleens and hemolytic activity of guinea pig complement in immunohemolytic reaction. Our findings, therefore, suggested that the moderate hepatoprotective effect of 6-MFA could be related to it's protective effect on hepatocyte plasma membrane rather than the direct inhibitory effects on the antibody formation and/or complement activity. PMID:10099025

  4. Invertebrate bioassays with North Sea water samples. I. Structural effects on embryos and larvae of serpulids, oysters and sea urchins

    NASA Astrophysics Data System (ADS)

    Klöckner, K.; Rosenthal, H.; Willführ, J.

    1985-03-01

    Structural effects of bottom and surface water samples from two dumping grounds in the inner German Bight on the development of three meroplanktonic organisms (Pomatoceros triqueter: Polychaeta, Psammechinus miliaris: Echinodermata and Crassostrea gigas, Mollusca) were investigated. The titaniumdioxide dumping site was sampled immediately after dumping (within the visible waste trail 1 km behind the vessel), and 10 h after dumping. Samples were taken in the sewage sludge deposition area in the intervals between the usual dumping activities, regardless of the exact dumping schedule. The preserved bioassay test organisms were inspected microscopically to count percentages of “normal” larval hatch in test water samples, reference water samples and laboratory aged control water samples (5 to 10 replicates). The relative water quality at various dumping sites was expressed in terms of “net risk”-values (Woelke, 1972) compared to hatching rates observed in the controls. Larval development of P. triqueter was significantly suppressed (up to -22 % “net risk”) in trail water of the titanium dioxide dump site while the development of sea urchin larvae was still affected in the 10 h surface samples. Hatching of all test organisms in bottom-water samples from the centre of the sewage sludge dump site was affected to different degrees when compared to reference areas about 4 km north or 6 km northwest of the dumping area. The general usefulness of standardized bioassay procedures in pollution monitoring programmes is discussed. The results presented here call for further verification to minimize experimental background variability and to enlarge the catalogue of suitable effects criteria.

  5. Keeping your seed head above water - EPA's research on the effects of sea level rise on sea grasses and emergent marshes in the Pacific Northwest

    EPA Science Inventory

    Global climate change, including sea-level rise (SLR), will have profound effects on estuarine fish, shellfish, and wildlife populations and their habitats. To develop an understanding of these potential impacts, the U.S. EPA at Newport, Oregon is participating in a joint researc...

  6. First assessment of effects of air-gun seismic shooting on marine resources in the central Adriatic sea

    SciTech Connect

    La Bella, G.; Cannata, S.; Froglia, C.

    1996-11-01

    A series of investigations were carried out to test the effects of air-gun seismic shooting on main fishery resources of the Adriatic Sea during summer 1995. The energy source used for the trial was formed by one air-gun array made up by two sub-arrays consisting in 8 air-guns each developing a total volume of c.a. 2500 i{sup 3} at 2000 psi with an amplitude of 60 bar/m. The interval between two was of 25 s. The intensity was of 210 dB re 1 mPa-m/Hz. Acoustical and spectral analysis were performed simultaneously in the surveyed areas to correlate fishery and behavior observations with sound pattern of the energization. Main results were: (1) Analysis of trawl catch data evidenced no significant changes before and after the air-gun seismic profiling. (2) Echosurvey relative estimate of pelagic biomass, performed simultaneously to trawling operations, failed to evidence any significant change in the pelagic biomass subsequent to the seismic shooting. (3) Small differences were observed in the trammel net catch composition, but one single set of pre-post fishing operations could be done in the study period. (4) Similar density estimate were obtained from dredge surveys performed by an hydraulic dredger before and after air-gun seismic profiling over a clam bed in 14 in depth. (5) Video recording of captive fish, kept into cages moored on the sea bottom at 12 in depth, evidenced a Behavioral response to the approach of the sound source; but no lethal event was recorded on captive sea-bass immediately after the seismic shooting. (6) Biochemical and histological analysis were performed to verify if it is to be related to the captive condition or is somewhat consequent to the air-gun energization. These results confirm that no relevant effects are induced on fishery resources by seismic air-gun shooting.

  7. Effects of sinking of salt rejected during formation of sea ice on results of an ocean-atmosphere-sea ice climate model

    NASA Astrophysics Data System (ADS)

    Duffy, P. B.; Eby, M.; Weaver, A. J.

    We show that results of an ocean-atmosphere-sea-ice model are sensitive to the treatment of salt rejected during formation of sea ice. In our Control simulation, we place all rejected salt in the top ocean-model level. In the Plume simulation, we instantaneously mix rejected salt into the subsurface ocean, to a maximum depth which depends on local density gradients. This mimics the effects of subgrid-scale convection of rejected salt. The results of the Plume simulation are more realistic than those of the Control simulation: the spatial pattern of simulated salinities (especially in the Southern Ocean), deep-ocean temperatures, simulated sea-ice extents and surface air temperatures all agree better with observations. A similar pair of simulations using horizontal tracer diffusion instead of the Gent-McWilliams eddy parameterization show similar changes due to instantaneous mixing of rejected salt.

  8. [Effect of stock abundance and environmental factors on the recruitment success of small yellow croaker in the East China Sea].

    PubMed

    Liu, Zun-lei; Yuan, Xing-wei; Yang, Lin-lin; Yan, Li-ping; Zhang, Hui; Cheng, Jia-hua

    2015-02-01

    Multiple hypotheses are available to explain recruitment rate. Model selection methods can be used to identify the best model that supports a particular hypothesis. However, using a single model for estimating recruitment success is often inadequate for overexploited population because of high model uncertainty. In this study, stock-recruitment data of small yellow croaker in the East China Sea collected from fishery dependent and independent surveys between 1992 and 2012 were used to examine density-dependent effects on recruitment success. Model selection methods based on frequentist (AIC, maximum adjusted R2 and P-values) and Bayesian (Bayesian model averaging, BMA) methods were applied to identify the relationship between recruitment and environment conditions. Interannual variability of the East China Sea environment was indicated by sea surface temperature ( SST) , meridional wind stress (MWS), zonal wind stress (ZWS), sea surface pressure (SPP) and runoff of Changjiang River ( RCR). Mean absolute error, mean squared predictive error and continuous ranked probability score were calculated to evaluate the predictive performance of recruitment success. The results showed that models structures were not consistent based on three kinds of model selection methods, predictive variables of models were spawning abundance and MWS by AIC, spawning abundance by P-values, spawning abundance, MWS and RCR by maximum adjusted R2. The recruitment success decreased linearly with stock abundance (P < 0.01), suggesting overcompensation effect in the recruitment success might be due to cannibalism or food competition. Meridional wind intensity showed marginally significant and positive effects on the recruitment success (P = 0.06), while runoff of Changjiang River showed a marginally negative effect (P = 0.07). Based on mean absolute error and continuous ranked probability score, predictive error associated with models obtained from BMA was the smallest amongst different

  9. [Effect of stock abundance and environmental factors on the recruitment success of small yellow croaker in the East China Sea].

    PubMed

    Liu, Zun-lei; Yuan, Xing-wei; Yang, Lin-lin; Yan, Li-ping; Zhang, Hui; Cheng, Jia-hua

    2015-02-01

    Multiple hypotheses are available to explain recruitment rate. Model selection methods can be used to identify the best model that supports a particular hypothesis. However, using a single model for estimating recruitment success is often inadequate for overexploited population because of high model uncertainty. In this study, stock-recruitment data of small yellow croaker in the East China Sea collected from fishery dependent and independent surveys between 1992 and 2012 were used to examine density-dependent effects on recruitment success. Model selection methods based on frequentist (AIC, maximum adjusted R2 and P-values) and Bayesian (Bayesian model averaging, BMA) methods were applied to identify the relationship between recruitment and environment conditions. Interannual variability of the East China Sea environment was indicated by sea surface temperature ( SST) , meridional wind stress (MWS), zonal wind stress (ZWS), sea surface pressure (SPP) and runoff of Changjiang River ( RCR). Mean absolute error, mean squared predictive error and continuous ranked probability score were calculated to evaluate the predictive performance of recruitment success. The results showed that models structures were not consistent based on three kinds of model selection methods, predictive variables of models were spawning abundance and MWS by AIC, spawning abundance by P-values, spawning abundance, MWS and RCR by maximum adjusted R2. The recruitment success decreased linearly with stock abundance (P < 0.01), suggesting overcompensation effect in the recruitment success might be due to cannibalism or food competition. Meridional wind intensity showed marginally significant and positive effects on the recruitment success (P = 0.06), while runoff of Changjiang River showed a marginally negative effect (P = 0.07). Based on mean absolute error and continuous ranked probability score, predictive error associated with models obtained from BMA was the smallest amongst different

  10. Effects of dietary vitamin C supplementation on lead-treated sea cucumbers, Apostichopus japonicus.

    PubMed

    Wang, Jing; Ren, Tongjun; Han, Yuzhe; Zhao, Yang; Liao, Mingling; Wang, Fuqiang; Jiang, Zhiqiang

    2015-08-01

    This study aimed to determine the effects of dietary supplementation with vitamin C (l-ascorbic acid, AsA) on lead (Pb) accumulation and toxicity in sea cucumber, Apostichopus japonicus. Three hundred sea cucumbers (10.02±0.02g) fed a basal diet containing 100mg Pb/kg were subjected to 5 levels of l-ascorbate-2-polyphosphate (LAPP) supplementation to achieve 5 AsA treatment levels of 0, 2727, 4630, 9171, 13,893mg AsA/kg. After 30 days, specific growth rate (SGR) and body weight gain (BWG) of supplementation groups were significantly (P<0.05) higher than the control group. Pb contents of the intestine significantly (P<0.05) decreased from 20 days to 30 days in all supplementation groups. Pb contents of the respiratory tree in sea cucumbers in the 2727 and 4630mg AsA/kg treatment groups significantly (P<0.05) decreased from 10 days to 30 days. Superoxide dismutase (SOD) activity, glutathione peroxidase (GSH-Px) activity and total antioxidant capacity (T-AOC) of the sea cucumber body wall in supplementation groups increased after 30 days. Malondialdehyde (MDA) content of the body wall significantly (P<0.05) declined with increasing AsA level. Therefore, it can be demonstrated that vitamin C could mitigate the effects of Pb on sea cucumber and the optimum levels ranged from 2727mg AsA/kg to 4630mg AsA/kg when Pb levels were 100mg/kg.

  11. The Effect of the South Asia Monsoon on the Wind Sea and Swell Patterns in the Arabian Sea

    NASA Astrophysics Data System (ADS)

    Semedo, Alvaro

    2015-04-01

    Ocean surface gravity waves have a considerable impact on coastal and offshore infrastructures, and are determinant on ship design and routing. But waves also play an important role on the coastal dynamics and beach erosion, and modulate the exchanges of momentum, and mass and other scalars between the atmosphere and the ocean. A constant quantitative and qualitative knowledge of the wave patterns is therefore needed. There are two types of waves at the ocean surface: wind-sea and swell. Wind-sea waves are growing waves under the direct influence of local winds; as these waves propagate away from their generation area, or when their phase speed overcomes the local wind speed, they are called swell. Swell waves can propagate thousands of kilometers across entire ocean basins. The qualitative analysis of ocean surface waves has been the focus of several recent studies, from the wave climate to the air-sea interaction community. The reason for this interest lies mostly in the fact that waves have an impact on the lower atmosphere, and that the air-sea coupling is different depending on the wave regime. Waves modulate the exchange of momentum, heat, and mass across the air-sea interface, and this modulation is different and dependent on the prevalence of one type of waves: wind sea or swell. For fully developed seas the coupling between the ocean-surface and the overlaying atmosphere can be seen as quasi-perfect, in a sense that the momentum transfer and energy dissipation at the ocean surface are in equilibrium. This can only occur in special areas of the Ocean, either in marginal seas, with limited fetch, or in Open Ocean, in areas with strong and persistent wind speed with little or no variation in direction. One of these areas is the Arabian Sea, along the coasts of Somalia, Yemen and Oman. The wind climate in the Arabian sea is under the direct influence of the South Asia monsoon, where the wind blows steady from the northeast during the boreal winter, and

  12. Global sea level rise and the greenhouse effect: Might they be connected

    SciTech Connect

    Peltier, W.R.; Tushingham, A.M. )

    1989-05-19

    Secular sea level trends extracted from tide gauge records of appropriately long duration demonstrate that global sea level may be rising at a rate in excess of 1 millimeter per year. However, because global coverage of the oceans by the tide gauge network is highly nonuniform and the tide gauge data reveal considerable spatial variability, there has been a well-founded reluctance to interpret the observed secular sea level rise as representing a signal of global scale that might be related to the greenhouse effect. When the tide gauge data are filtered so as to remove the contribution of ongoing glacial isostatic adjustement to the local sea level trend at each location, then the individual tide gauge records reveal sharply reduced geographic scatter and suggest that there is a globally coherent signal of strength 2.4 {plus minus} 0.90 millimeters per year that is active in the system. This signal could constitute an indication of global climate warming. 15 refs., 8 figs.

  13. The effect of rising sea level on the hydrology of coastal watersheds

    NASA Astrophysics Data System (ADS)

    Nuttle, William K.

    1992-06-01

    Rising sea level will increase surface runoff and decrease groundwater discharge from low-lying coastal areas by raising the water table and thus saturating the soil. As a result, there will be increased upland flooding by freshwater and changes in the productive intertidal and near-shore ecosystems that depend on the lowered salinities and nutrients provided by groundwater discharge. This paper compares these effects of future increases in sea level with the present variation in runoff and groundwater discharge caused by interannual variations in precipitation and evaporation. The analysis relies on a water balance model calibrated using data from a small watershed on Cape Cod (USA). Interannual variation of runoff and groundwater discharge is estimated by driving the model with 40 years of historical weather data. The results indicate that a 20 cm rise in sea level will double the mean surface runoff and reduce groundwater discharge by half. These conditions are significantly different than the present mean hydrologic conditions. The variability of surface runoff also increases with rising sea level.

  14. The Effects of Highly Detailed Urban Roughness Parameters on a Sea-Breeze Numerical Simulation

    NASA Astrophysics Data System (ADS)

    Varquez, Alvin Christopher G.; Nakayoshi, Makoto; Kanda, Manabu

    2015-03-01

    We consider the effects of detailed urban roughness parameters on a sea-breeze simulation. An urban roughness database, constructed using a new aerodynamic parametrization derived from large-eddy simulations, was incorporated as a surface boundary condition in the advanced Weather Research and Forecasting model. The zero-plane displacement and aerodynamic roughness length at several densely built-up urban grids were three times larger than conventional values due to the consideration of building-height variability. A comparison between simulations from the modified model and its default version, which uses uniform roughness parameters within a conventional method, was conducted for a 2-month period during summer. Results showed a significant improvement in the simulation of surface wind speed but not with temperature. From the 2-month study period, a day with an evident sea-breeze penetration was selected and simulated at higher temporal resolution. Sea-breeze penetration weakened and was more delayed over urbanized areas. The slow sea-breeze penetration also lessened heat advection downwind allowing stronger turbulent mixing and a deeper boundary layer above urban areas. Horizontal wind-speed reduction due to the increased urban surface drag reached heights of several hundreds of metres due to the strong convection.

  15. Discrimination of sediment provenance in the Yellow Sea: Secondary grain-size effect and REE proxy

    NASA Astrophysics Data System (ADS)

    Jung, Hoi-Soo; Lim, Dhongil; Jeong, Do-Hyun; Xu, Zhaokai; Li, Tiegang

    2016-06-01

    This study analyzed grain size and elemental concentrations (Al, Mg, Fe, and rare earth elements (REEs)) in 91 surface sediments to elucidate sediment provenance in the Yellow Sea. Elemental concentrations were normalized by Al concentration (Celement/CAl) to minimize the sediment grain-size effect (GSE). However, noticeable linear relationships between Al concentration (or mean grain size) and the ratio (e.g., Mg/Al or Fe/Al) appeared unexpectedly in pair diagrams. The spatial distribution patterns of Fe/Al and Mg/Al ratios were also similar to the pattern of mean grain size. This implies that the GSE was not removed completely, even after the normalization process. Thus, great care must be taken when applying the ratios of Celement/CAl as a proxy of sediment provenance. To improve provenance discrimination of the sediments in the Yellow Sea, the difference between the REE distribution patterns of Chinese and Korean river sediments, expressed as δ (δ = REE∗(La) - REE∗(Lu)), was calculated, and the spatial distribution patterns of the δ values were mapped. The δ values gradually increased from the western to the eastern part of the Yellow Sea, except for low δ values in the southeastern part of the Yellow Sea. This result indicates that the majority of Chinese and Korean river sediments are accumulating near to their respective coasts, except for a deposit along the southwestern coast of Korea in which a considerable amount of sediment from Chinese rivers has been accumulating.

  16. Determination of chemical composition and genotoxic effects of essential oil obtained from Nepeta nuda on Zea mays seedlings.

    PubMed

    Bozari, Sedat; Agar, Guleray; Aksakal, Ozkan; Erturk, Filiz A; Yanmis, Derya

    2013-05-01

    We aimed to determine the genotoxic potential of essential oil (EO) obtained from Nepeta nuda. The chemical content of EO was measured via gas chromatography/mass spectrometry. The most abundant contents were 4aα,7β,7aα-nepetalactone (18.10%), germacrene (15.68%) and elemol (14.38%). For genotoxic effects of EO, Zea mays' seeds were exposed to four different concentrations of this oil. Inhibition of root and stem growth were observed with an increase in EO concentrations. Randomly amplified polymorphic DNA (RAPD) method was used to determine the genotoxic effects of EO. Some changes occurred in RAPD profiles of germinated EO-treated seeds. Even though total soluble protein quantity vary, the data observed from the protein profiles of sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that there was a little differentiation between band profiles of treated samples and control group. We concluded that the basis of interactions between plants, like allelopathy, may be related with genotoxic effects of EO.

  17. Determination of chemical composition and genotoxic effects of essential oil obtained from Nepeta nuda on Zea mays seedlings.

    PubMed

    Bozari, Sedat; Agar, Guleray; Aksakal, Ozkan; Erturk, Filiz A; Yanmis, Derya

    2013-05-01

    We aimed to determine the genotoxic potential of essential oil (EO) obtained from Nepeta nuda. The chemical content of EO was measured via gas chromatography/mass spectrometry. The most abundant contents were 4aα,7β,7aα-nepetalactone (18.10%), germacrene (15.68%) and elemol (14.38%). For genotoxic effects of EO, Zea mays' seeds were exposed to four different concentrations of this oil. Inhibition of root and stem growth were observed with an increase in EO concentrations. Randomly amplified polymorphic DNA (RAPD) method was used to determine the genotoxic effects of EO. Some changes occurred in RAPD profiles of germinated EO-treated seeds. Even though total soluble protein quantity vary, the data observed from the protein profiles of sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that there was a little differentiation between band profiles of treated samples and control group. We concluded that the basis of interactions between plants, like allelopathy, may be related with genotoxic effects of EO. PMID:22312034

  18. [The Xanthine Oxidase Inhibitory Activity and Hypouricemic Effects of Crude Drugs Obtained from the Silkworm in Mice].

    PubMed

    Tanaka, Ryuichirou; Miyata, Yuuma; Minakuchi, Naoki; Murakami, Ayako; Sakazaki, Fumitoshi

    2015-01-01

    This study evaluated the effects of crude drugs obtained from the silkworm in mice with oxonic acid-induced hyperuricemia using xanthine oxidase inhibitory activity and plasma uric acid levels. The plasma uric acid level was analyzed using an improved HPLC with UV detection (HPLC-UV) method, which enabled high-sensitivity analysis of a microliter of plasma. Using this method, we evaluated natural products administered orally to the hypouricemic mice. The plasma uric acid level of mice administered a water-soluble extract from silkworm larvae with botrytis (used in traditional Chinese medicine to reduce wind, lower blood pressure, and change platelet coagulation) was significantly lower than in the control group 1, 2, and 3 h after treatment. In addition, water soluble extracts from a fungus (NBRC 31161) metabolite and silkworm pupae and larvae reduced the plasma uric acid levels in mice compared with the control group.

  19. Substrate-independent sequential deposition process to obtain the lotus effect based on mussel-inspired polydopamine

    NASA Astrophysics Data System (ADS)

    Ou, Junfei; Pan, Bing; Chen, Yiwei; Xie, Chan; Xue, Mingshan; Wang, Fajun; Li, Wen

    2015-02-01

    A substrate-independent route to achieve the lotus effect on a variety of substrates is proposed based on mussel-inspired polydopamine (PDA), and was tested on titanium alloy, polypropylene and silicon substrates. The substrates were firstly coated with PDA and then sequentially transferred to aqueous CuCl2 and AgNO3 solutions for copper and silver deposition. Finally, the samples were passivated by the low-surface-energy molecules of 1-dodecanethiol, and surface superhydrophobicity (contact angle > 160°; sliding angle between 1° and 2°) could be obtained. Due to the strong adhesion of PDA to a wide range of materials, it is expected that this deposition process can be applied to a variety of other substrates including metal, polymer, and inorganic-nonmetallic materials.

  20. [The Xanthine Oxidase Inhibitory Activity and Hypouricemic Effects of Crude Drugs Obtained from the Silkworm in Mice].

    PubMed

    Tanaka, Ryuichirou; Miyata, Yuuma; Minakuchi, Naoki; Murakami, Ayako; Sakazaki, Fumitoshi

    2015-01-01

    This study evaluated the effects of crude drugs obtained from the silkworm in mice with oxonic acid-induced hyperuricemia using xanthine oxidase inhibitory activity and plasma uric acid levels. The plasma uric acid level was analyzed using an improved HPLC with UV detection (HPLC-UV) method, which enabled high-sensitivity analysis of a microliter of plasma. Using this method, we evaluated natural products administered orally to the hypouricemic mice. The plasma uric acid level of mice administered a water-soluble extract from silkworm larvae with botrytis (used in traditional Chinese medicine to reduce wind, lower blood pressure, and change platelet coagulation) was significantly lower than in the control group 1, 2, and 3 h after treatment. In addition, water soluble extracts from a fungus (NBRC 31161) metabolite and silkworm pupae and larvae reduced the plasma uric acid levels in mice compared with the control group. PMID:26423873

  1. Axial Anomaly, Dirac Sea, and the Chiral Magnetic Effect

    SciTech Connect

    Kharzeev, D.E.

    2010-05-26

    Gribov viewed the axial anomaly as a manifestation of the collective motion of Dirac fermions with arbitrarily high momenta in the vacuum. In the presence of an external magnetic field and a chirality imbalance, this collective motion becomes directly observable in the form of the electric current - this is the chiral magnetic effect (CME). I give an elementary introduction into the physics of CME, and discuss the experimental status and recent developments.

  2. Chemical composition and phytotoxic effects of essential oils obtained from Ailanthus altissima (Mill.) swingle cultivated in Tunisia.

    PubMed

    El Ayeb-Zakhama, Asma; Ben Salem, Saoussen; Sakka-Rouis, Lamia; Flamini, Guido; Ben Jannet, Hichem; Harzallah-Skhiri, Fethia

    2014-08-01

    Ailanthus altissima Mill. Swingle (Simaroubaceae), also known as tree of heaven, is used in the Chinese traditional medicine as a bitter aromatic drug for the treatment of colds and gastric diseases. In Tunisia, Ailanthus altissima is an exotic tree, which was introduced many years ago and used particularly as a street ornamental tree. Here, the essential oils of different plant parts of this tree, viz., roots, stems, leaves, flowers, and samaras (ripe fruits), were obtained by hydrodistillation. In total, 69 compounds, representing 91.0-97.2% of the whole oil composition, were identified in these oils by GC-FID and GC/MS analyses. The root essential oil was clearly distinguishable for its high content in aldehydes (hexadecanal (1); 22.6%), while those obtained from flowers and leaves were dominated by oxygenated sesquiterpenes (74.8 and 42.1%, resp.), with caryophyllene oxide (4) as the major component (42.5 and 22.7%, resp.). The samara oil was rich in the apocarotenoid derivative hexahydrofarnesyl acetone (6; 58.0%), and the oil obtained from stems was characterized by sesquiterpene hydrocarbons (54.1%), mainly β-caryophyllene (18.9%). Principal component and hierarchical cluster analyses separated the five essential oils into four groups, each characterized by the major oil constituents. Contact tests showed that the germination of lettuce seeds was totally inhibited by all the essential oils except of the samara oil at a dose of 1 mg/ml. The flower oil also showed a significant phytotoxic effect against lettuce germination at 0.04 and 0.4 mg/ml (-55.0 ± 3.5 and -85.0 ± 0.7%, resp.). Moreover, the root and shoot elongation was even more affected by the oils than germination. The inhibitory effect of the shoot and root elongation varied from -9.8 to -100% and from -38.6 to -100%, respectively. Total inhibition of the elongation (-100%) at 1 mg/ml was detected for all the oils, with the exception of the samara oil (-74.7 and -75.1% for roots and shoots, resp.).

  3. Chemical composition and phytotoxic effects of essential oils obtained from Ailanthus altissima (Mill.) swingle cultivated in Tunisia.

    PubMed

    El Ayeb-Zakhama, Asma; Ben Salem, Saoussen; Sakka-Rouis, Lamia; Flamini, Guido; Ben Jannet, Hichem; Harzallah-Skhiri, Fethia

    2014-08-01

    Ailanthus altissima Mill. Swingle (Simaroubaceae), also known as tree of heaven, is used in the Chinese traditional medicine as a bitter aromatic drug for the treatment of colds and gastric diseases. In Tunisia, Ailanthus altissima is an exotic tree, which was introduced many years ago and used particularly as a street ornamental tree. Here, the essential oils of different plant parts of this tree, viz., roots, stems, leaves, flowers, and samaras (ripe fruits), were obtained by hydrodistillation. In total, 69 compounds, representing 91.0-97.2% of the whole oil composition, were identified in these oils by GC-FID and GC/MS analyses. The root essential oil was clearly distinguishable for its high content in aldehydes (hexadecanal (1); 22.6%), while those obtained from flowers and leaves were dominated by oxygenated sesquiterpenes (74.8 and 42.1%, resp.), with caryophyllene oxide (4) as the major component (42.5 and 22.7%, resp.). The samara oil was rich in the apocarotenoid derivative hexahydrofarnesyl acetone (6; 58.0%), and the oil obtained from stems was characterized by sesquiterpene hydrocarbons (54.1%), mainly β-caryophyllene (18.9%). Principal component and hierarchical cluster analyses separated the five essential oils into four groups, each characterized by the major oil constituents. Contact tests showed that the germination of lettuce seeds was totally inhibited by all the essential oils except of the samara oil at a dose of 1 mg/ml. The flower oil also showed a significant phytotoxic effect against lettuce germination at 0.04 and 0.4 mg/ml (-55.0 ± 3.5 and -85.0 ± 0.7%, resp.). Moreover, the root and shoot elongation was even more affected by the oils than germination. The inhibitory effect of the shoot and root elongation varied from -9.8 to -100% and from -38.6 to -100%, respectively. Total inhibition of the elongation (-100%) at 1 mg/ml was detected for all the oils, with the exception of the samara oil (-74.7 and -75.1% for roots and shoots, resp

  4. The study of the hydrological regime extreme effects of the Caspian Sea during the XX-XXI centuries

    NASA Astrophysics Data System (ADS)

    Yaitskaya, Natalia

    2016-04-01

    The Caspian Sea - the unique largest enclosed inland body of water on Earth. Significant periodic sea level fluctuations are a typical feature of the sea. In the XIX-XX centuries a number of comprehensive studies of the Caspian Sea was carried out. The results are published in the papers, monographs and climatic atlases. But a number of fundamental questions about the features of the hydrological regime of the Caspian Sea is still open: 1. How does the water circulation change during the level variations? 2. What is the effect of heterogeneity of evaporation from the water surface on the formation of the flow field in the conditions of long-term level changes? 3. How does the water salinity regime change depending on the sea level position, water circulation, river flow and different climatic influences? 4. What is the effect of extreme events (multi-hazards) (ice, storms, destruction of the coasts) on coastal infrastructure? In 2016, the project aims to study hydrological regime extreme effects of the Caspian Sea was supported by the Russian Foundation for Basic Research. Within this project all of the above problems will be solved. Geographic information system "Caspian Sea" for the storage and data processing, including a database of primary oceanographic information for the period of instrumental observations (1897-2013), cartographic database (1921-2011) and tools for multidimensional analysis of spatio-temporal information is the basis of the study. The scheme of interconnected hydrodynamic models (Caspian Sea MODel - Ocean Model - Wind wave model) was developed. The important factors are taken into account in the structure of the models: long-term and seasonal dynamics of the sea waves parameters, new long-term values of evaporation from the shallow waters areas of the Caspian Sea, water circulation. Schemes of general seasonal circulation of the Caspian Sea and the Northern Caspian at different positions of the sea level in XX-XXI centuries using

  5. Oxygen depletion in coastal seas and the effective spawning stock biomass of an exploited fish species

    PubMed Central

    Hinrichsen, H.-H.; von Dewitz, B.; Dierking, J.; Haslob, H.; Makarchouk, A.; Petereit, C.; Voss, R.

    2016-01-01

    Environmental conditions may have previously underappreciated effects on the reproductive processes of commercially exploited fish populations, for example eastern Baltic cod, that are living at the physiological limits of their distribution. In the Baltic Sea, salinity affects neutral egg buoyancy, which is positively correlated with egg survival, as only water layers away from the oxygen consumption-dominated sea bottom contain sufficient oxygen. Egg buoyancy is positively correlated to female spawner age/size. From observations in the Baltic Sea, a field-based relationship between egg diameter and buoyancy (floating depth) could be established. Hence, based on the age structure of the spawning stock, we quantify the number of effective spawners, which are able to reproduce under ambient hydrographic conditions. For the time period 1993–2010, our results revealed large variations in the horizontal extent of spawning habitat (1000–20 000 km2) and oxygen-dependent egg survival (10–80%). The novel concept of an effective spawning stock biomass takes into account offspring that survive depending on the spawning stock age/size structure, if reproductive success is related to egg buoyancy and the extent of hypoxic areas. Effective spawning stock biomass reflected the role of environmental conditions for Baltic cod recruitment better than the spawning stock biomass alone, highlighting the importance of including environmental information in ecosystem-based management approaches. PMID:26909164

  6. Oxygen depletion in coastal seas and the effective spawning stock biomass of an exploited fish species.

    PubMed

    Hinrichsen, H-H; von Dewitz, B; Dierking, J; Haslob, H; Makarchouk, A; Petereit, C; Voss, R

    2016-01-01

    Environmental conditions may have previously underappreciated effects on the reproductive processes of commercially exploited fish populations, for example eastern Baltic cod, that are living at the physiological limits of their distribution. In the Baltic Sea, salinity affects neutral egg buoyancy, which is positively correlated with egg survival, as only water layers away from the oxygen consumption-dominated sea bottom contain sufficient oxygen. Egg buoyancy is positively correlated to female spawner age/size. From observations in the Baltic Sea, a field-based relationship between egg diameter and buoyancy (floating depth) could be established. Hence, based on the age structure of the spawning stock, we quantify the number of effective spawners, which are able to reproduce under ambient hydrographic conditions. For the time period 1993-2010, our results revealed large variations in the horizontal extent of spawning habitat (1000-20 000 km(2)) and oxygen-dependent egg survival (10-80%). The novel concept of an effective spawning stock biomass takes into account offspring that survive depending on the spawning stock age/size structure, if reproductive success is related to egg buoyancy and the extent of hypoxic areas. Effective spawning stock biomass reflected the role of environmental conditions for Baltic cod recruitment better than the spawning stock biomass alone, highlighting the importance of including environmental information in ecosystem-based management approaches.

  7. Oxygen depletion in coastal seas and the effective spawning stock biomass of an exploited fish species.

    PubMed

    Hinrichsen, H-H; von Dewitz, B; Dierking, J; Haslob, H; Makarchouk, A; Petereit, C; Voss, R

    2016-01-01

    Environmental conditions may have previously underappreciated effects on the reproductive processes of commercially exploited fish populations, for example eastern Baltic cod, that are living at the physiological limits of their distribution. In the Baltic Sea, salinity affects neutral egg buoyancy, which is positively correlated with egg survival, as only water layers away from the oxygen consumption-dominated sea bottom contain sufficient oxygen. Egg buoyancy is positively correlated to female spawner age/size. From observations in the Baltic Sea, a field-based relationship between egg diameter and buoyancy (floating depth) could be established. Hence, based on the age structure of the spawning stock, we quantify the number of effective spawners, which are able to reproduce under ambient hydrographic conditions. For the time period 1993-2010, our results revealed large variations in the horizontal extent of spawning habitat (1000-20 000 km(2)) and oxygen-dependent egg survival (10-80%). The novel concept of an effective spawning stock biomass takes into account offspring that survive depending on the spawning stock age/size structure, if reproductive success is related to egg buoyancy and the extent of hypoxic areas. Effective spawning stock biomass reflected the role of environmental conditions for Baltic cod recruitment better than the spawning stock biomass alone, highlighting the importance of including environmental information in ecosystem-based management approaches. PMID:26909164

  8. Gastroprotective effect of alpha-pinene and its correlation with antiulcerogenic activity of essential oils obtained from Hyptis species

    PubMed Central

    Pinheiro, Marcelo de Almeida; Magalhães, Rafael Matos; Torres, Danielle Mesquita; Cavalcante, Rodrigo Cardoso; Mota, Francisca Sheila Xavier; Oliveira Coelho, Emanuela Maria Araújo; Moreira, Henrique Pires; Lima, Glauber Cruz; Araújo, Pamella Cristina da Costa; Cardoso, José Henrique Leal; de Souza, Andrelina Noronha Coelho; Diniz, Lúcio Ricardo Leite

    2015-01-01

    Background: Alpha-pinene (α-pinene) is a monoterpene commonly found in essential oils with gastroprotective activity obtained from diverse medicinal plants, including Hyptis species. The genus Hyptis (lamiaceae) consists of almost 400 species widespread in tropical and temperate regions of America. In the north and northeastern Brazil, some Hyptis species are used in traditional medicine to treat gastrointestinal disturbances. Objective: The present study has investigated the gastoprotective effect of purified α-pinene in experimental gastric ulcer induced by ethanol and indomethacin in mice. Materials and Methods: Gastric ulcers were induced in male Swiss mice (20-30 g) by oral administration of absolute ethanol or indomethacin 45 min after oral pretreatment with vehicle, standard control drugs or α-pinene (10, 30, and 100 mg/kg). One hour after the ulcerative challenges, the stomach were removed, and gastric lesions areas measured. The effects of α-pinene on the gastric juice acidity were determined by pylorus ligation model. The gastrointestinal motility and mucus depletion were determined by measuring the gastric levels of phenol red and alcian blue, respectively. Hematoxylin and eosin stained sections of gastric mucosa of the experimental groups were used for histology analysis. Results: α-pinene pretreatment inhibited ethanol-induced gastric lesions, reduced volume and acidity of the gastric juice and increased gastric wall mucus (P < 0.05). Furthermore, we showed an interesting correlation between concentration of α-pinene and gastroprotective effect of Hyptis species (P Pearson = 0.98). Conclusion: Our data showed that the α-pinene exhibited significant antiulcerogenic activity and a great correlation between concentration of α-pinene and gastroprotective effect of Hyptis species was also observed. PMID:25709221

  9. The effect of wind-generated bubbles on sea-surface backscattering at 940 Hz.

    PubMed

    van Vossen, Robbert; Ainslie, Michael A

    2011-11-01

    Reliable predictions of sea-surface backscattering strength are required for sonar performance modeling. These are, however, difficult to obtain as measurements of sea-surface backscattering are not available at small grazing angles relevant to low-frequency active sonar (1-3 kHz). Accurate theoretical predictions of scattering strength require a good understanding of physical mechanisms giving rise to the scattering and the relative importance of these. In this paper, scattering from individual resonant bubbles is introduced as a potential mechanism and a scattering model is derived that incorporates the contribution from these together with that of rough surface scattering. The model results are fitted to Critical Sea Test (CST) measurements at a frequency of 940 Hz, treating the number of large bubbles, parameterized through the spectral slope of the size spectrum for bubbles whose radii exceed 1 mm, as a free parameter. This procedure illustrates that the CST data can be explained by scattering from a small number of large resonant bubbles, indicating that these provide an alternative mechanism to that of scattering from bubble clouds.

  10. The Effects of Changing Sea Ice on Marine Mammals and Their Hunters in Northern Alaska

    NASA Astrophysics Data System (ADS)

    Huntington, H.; Quakenbush, L.; Nelson, M.

    2015-12-01

    Marine mammals are important sources of food for indigenous residents of northern Alaska. Changing sea ice patterns affect the animals themselves as well as access by hunters. Documenting the traditional knowledge of Iñupiaq and Yupik hunters concerning marine mammals and sea ice makes accessible a wide range of information and insight relevant to ecological understanding, conservation action, and the regulation of human activity. We interviewed hunters in villages from northern Bering Sea to the Beaufort Sea, focusing on bowhead whales, walrus, and ice seals. Hunters reported extensive changes in sea ice, with resulting effects on the timing of marine mammal migrations, the distribution and behavior of the animals, and the efficacy of certain hunting methods, for example the difficulty of finding ice thick enough to support a bowhead whale for butchering. At the same time, hunters acknowledged impacts and potential impacts from changing technology such as more powerful outboard engines and from industrial activity such as shipping and oil and gas development. Hunters have been able to adapt to some changes, for example by hunting bowhead whales in fall as well as spring on St. Lawrence Island, or by focusing their hunt in a shorter period in Nuiqsut to accommodate work schedules and worse weather. Other changes, such as reduced availability of ice seals due to rapid retreat of pack ice after spring break-up, continue to defy easy responses. Continued environmental changes, increased disturbance from human activity, and the introduction of new regulations for hunting may further challenge the ability of hunters to provide food as they have done to date, though innovation and flexibility may also provide new sources of adaptation.

  11. Effects of the winter of 1976-1977 on the northwestern sargasso sea.

    PubMed

    Leetmaa, A

    1977-10-14

    A survey was conducted in the northwestern Sargasso Sea during the spring to assess the effect and extent of the winter cooling of 1976 to 1977 on the ocean. Newly formed, well-mixed layers of 18 degrees C water as deep as 550 meters were observed. The main thermocline south of the Gulf Stream was 100 to 150 meters deeper than it is on the average, which implies significant changes in the baroclinic transports.

  12. Neural electrophysiological effect of crude venom of conus textile from the south China Sea.

    PubMed

    Yang, D M; Hu, K P; Li, C Y; Wu, C H; Zhou, P A

    2000-11-01

    In the present study, we characterized effects of the crude venom from Conus textile, a marine molluscivorous snail collected from the South China Sea, on neural electrophysiological activity in insect, molluscan and mammalian species. Our results demonstrate that the venom reversibly blocks the cholinergic synaptic transmission of cockroach Periplaneta americana central nervous system, partially blocks Na(+) currents in rat hippocampal CA(1) pyramidal neurons, and enhances the excitability and spontaneous activity of the giant neurons of garden snail Achatina fulica.

  13. The effect of carotenoids obtained from saffron on histone H1 structure and H1-DNA interaction.

    PubMed

    Ashrafi, M; Bathaie, S Z; Taghikhani, M; Moosavi-Movahedi, A A

    2005-09-15

    It is already known that transcriptional activation of genes occurs due to the H1 dissociation from linker DNA; hence, histone H1-DNA complex is considered as a model of chromatin. Anticancer property of saffron and its carotenoids has already been reported. The present study aimed at investigating the effect of saffron carotenoids on H1 structure and H1-DNA interaction as a possible mechanism of their anticarcinogenic action. After purification of the saffron carotenoids (crocin, crocetin and dimethylcrocetin), their interaction with histone H1 was studied using spectrophotometry and spectrofluorometry. Some changes on the absorption spectra of H1 indicated the complex formation between this protein and saffron carotenoids. Also, the fluorescence emission of H1 was quenched by the mentioned ligands. The binding parameters of all the three ligands were obtained through Schatchard analysis of the quenching data. Then, the effect of each ligand on the H1-DNA interaction was studied. The results showed a shift in the precipitation curve to the left in the presence of the mentioned carotenoids, which is due to the reduction in the interaction of H1 with DNA. These observations led to the suggesting a mechanism in which the H1 depletion may promote transcription.

  14. Effects of Temperature and Pore Structure on High Surface Area-Activated Carbon Obtained from Peanut Shells.

    PubMed

    Kalpana, D; Lee, Y S

    2016-03-01

    Activated carbon was synthesized from peanut shells by treating with H3PO4 with an intention to enhance the surface area and to find its electrochemical performance in EDLC as electrode material. The powdered peanut shells were pyrolyzed at three different temperatures namely 300 degrees C, 600 degrees C and 800 degrees C respectively. The structural and surface properties of the pyrolyzed carbon materials were studied using N2 adsorption/desorption, Raman, TEM and SEM analysis. There has been remarkable increase in the surface area of the carbon pyrolyzed at 600 degrees C due to the effect of pore generations. The surface area of the 600 degrees C pyrolyzed sample was found to be 1629 m2/g. The electrochemical properties of all the samples were evaluated by cyclic voltammetry, impedance spectroscopy, and galvanostatic charge-discharge tests. The system showed excellent cycleability and a maximum specific capacitance of 291 Fg(-1) was obtained in a 0.1 M H2SO4 electrolyte solution. The effects of the various properties of the activated carbon on the EDLC performance are discussed. PMID:27455740

  15. Effects of Temperature and Pore Structure on High Surface Area-Activated Carbon Obtained from Peanut Shells.

    PubMed

    Kalpana, D; Lee, Y S

    2016-03-01

    Activated carbon was synthesized from peanut shells by treating with H3PO4 with an intention to enhance the surface area and to find its electrochemical performance in EDLC as electrode material. The powdered peanut shells were pyrolyzed at three different temperatures namely 300 degrees C, 600 degrees C and 800 degrees C respectively. The structural and surface properties of the pyrolyzed carbon materials were studied using N2 adsorption/desorption, Raman, TEM and SEM analysis. There has been remarkable increase in the surface area of the carbon pyrolyzed at 600 degrees C due to the effect of pore generations. The surface area of the 600 degrees C pyrolyzed sample was found to be 1629 m2/g. The electrochemical properties of all the samples were evaluated by cyclic voltammetry, impedance spectroscopy, and galvanostatic charge-discharge tests. The system showed excellent cycleability and a maximum specific capacitance of 291 Fg(-1) was obtained in a 0.1 M H2SO4 electrolyte solution. The effects of the various properties of the activated carbon on the EDLC performance are discussed.

  16. Effect of Sampling Depth on Air-Sea CO2 Flux Estimates in River-Stratified Arctic Coastal Waters

    NASA Astrophysics Data System (ADS)

    Miller, L. A.; Papakyriakou, T. N.

    2015-12-01

    In summer-time Arctic coastal waters that are strongly influenced by river run-off, extreme stratification severely limits wind mixing, making it difficult to effectively sample the surface 'mixed layer', which can be as shallow as 1 m, from a ship. During two expeditions in southwestern Hudson Bay, off the Nelson, Hayes, and Churchill River estuaries, we confirmed that sampling depth has a strong impact on estimates of 'surface' pCO2 and calculated air-sea CO2 fluxes. We determined pCO2 in samples collected from 5 m, using a typical underway system on the ship's seawater supply; from the 'surface' rosette bottle, which was generally between 1 and 3 m; and using a niskin bottle deployed at 1 m and just below the surface from a small boat away from the ship. Our samples confirmed that the error in pCO2 derived from typical ship-board versus small-boat sampling at a single station could be nearly 90 μatm, leading to errors in the calculated air-sea CO2 flux of more than 0.1 mmol/(m2s). Attempting to extrapolate such fluxes over the 6,000,000 km2 area of the Arctic shelves would generate an error approaching a gigamol CO2/s. Averaging the station data over a cruise still resulted in an error of nearly 50% in the total flux estimate. Our results have implications not only for the design and execution of expedition-based sampling, but also for placement of in-situ sensors. Particularly in polar waters, sensors are usually deployed on moorings, well below the surface, to avoid damage and destruction from drifting ice. However, to obtain accurate information on air-sea fluxes in these areas, it is necessary to deploy sensors on ice-capable buoys that can position the sensors in true 'surface' waters.

  17. The dynamic effects of sea level rise on low-gradient coastal landscapes: A review

    USGS Publications Warehouse

    Passeri, Davina; Hagen, Scott C.; Medeiros, Stephen C.; Bilskie, Matthew V.; Alizad, Karim; Wang, Dingbao

    2015-01-01

    Coastal responses to sea level rise (SLR) include inundation of wetlands, increased shoreline erosion, and increased flooding during storm events. Hydrodynamic parameters such as tidal ranges, tidal prisms, tidal asymmetries, increased flooding depths and inundation extents during storm events respond nonadditively to SLR. Coastal morphology continually adapts toward equilibrium as sea levels rise, inducing changes in the landscape. Marshes may struggle to keep pace with SLR and rely on sediment accumulation and the availability of suitable uplands for migration. Whether hydrodynamic, morphologic, or ecologic, the impacts of SLR are interrelated. To plan for changes under future sea levels, coastal managers need information and data regarding the potential effects of SLR to make informed decisions for managing human and natural communities. This review examines previous studies that have accounted for the dynamic, nonlinear responses of hydrodynamics, coastal morphology, and marsh ecology to SLR by implementing more complex approaches rather than the simplistic “bathtub” approach. These studies provide an improved understanding of the dynamic effects of SLR on coastal environments and contribute to an overall paradigm shift in how coastal scientists and engineers approach modeling the effects of SLR, transitioning away from implementing the “bathtub” approach. However, it is recommended that future studies implement a synergetic approach that integrates the dynamic interactions between physical and ecological environments to better predict the impacts of SLR on coastal systems.

  18. Observations of the 18.6-year cycle effects on the sea-level oscillations in the North Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Capuano, P.; De Lauro, E.; De Martino, S.; Falanga, M.

    2012-11-01

    We investigate the physical processes that generate the ocean tides, whose understanding has important influence on the marine activities. We analyze historical sea-level oscillations, continuously recorded from six stations in the North Atlantic Ocean spanning a time period of eighty years from 1926. In this paper, an Independent-Component-Analysis-based approach is adopted to obtain a clear identification of the main tidal constituents in term of waveform in time domain from the simultaneously recorded signals. This technique separates at most six nonlinear tidal components which are weakly superimposed. The fundamental objective is to extract information on the degree of complexity of the involved dynamics and on the very long-term tidal constituents. This is particularly significant to understand the response of the ocean to the tidal forcing. We put the emphasis on the near-bidecadal time scale and its influence on the short-periods tides. In details the Moon 18.6 y nodal cycle modulation acts in the ocean in quite an analogous manner to the fortnightly modulation in many shallow seas. Our results give new insights into the evidence for an 18.6 y effect in the climate/ocean variation whose physical mechanism details remain murky.

  19. Biological effects: Marine mammals and sea turtles (chapter 14). Book chapter

    SciTech Connect

    Haebler, R.

    1994-01-01

    All spills are different, varying in type and amount of oil spilled, species exposed, and geographic and atmospheric conditions. It is important to understand as much as possible about both the natural history and characteristics of various species and the specific effects oil has on wildlife. Doing so improves the ability to extrapolate from one spill to another and improves prediction of types and severity of effects to wildlife. This chapter presents an overview of the biological effects of oil on marine mammals and sea turtles.

  20. Beaufort Sea: information update

    SciTech Connect

    Becker, P.R.

    1988-04-01

    The report is based on a multi-disciplinary meeting held March 6-7, 1985, as part of preparations for the Beaufort Sea Sale 97. The chapters are based on presentations given: The causeway effect: Modification of nearshore thermal regime resulting from causeways; Summertime sea ice intrusions in the Chukchi Sea; The deepwater limit of ice gouging on the Beaufort Sea shelf; Distribution, abundance, migration, harvest, and stock identity of Belukha Whales in the Beaufort Sea; Ringed seals in the Beaufort Sea; Beaufort Sea socioeconomics; The Baffin Island Oil Spill, (BIOS) Project.

  1. Effects of light polarization and waves slope statistics on the reflectance factor of the sea surface.

    PubMed

    D'Alimonte, Davide; Kajiyama, Tamito

    2016-04-18

    Above-water radiometry depends on estimates of the reflectance factor ρ of the sea surface to compute the in situ water-leaving radiance. The Monte Carlo code for ocean color simulations MOX is used in this study to analyze the effect of different environmental components on ρ values. A first aspect is examining the reflectance factor without and by accounting for the sky-radiance polarization. The influence of the sea-surface statistics at discrete grid points is then considered by presenting a new scheme to define the variance of the waves slope. Results at different sun elevations and sensor orientations indicate that the light polarization effect on ρ simulations reduces from ∼17 to ∼10% when the wind speed increases from 0 to 14m s-1. An opposite tendency characterizes the modeling of the sea-surface slope variance, with ρ differences up to ∼12% at a wind speed of 10m s-1. The joint effect of polarization and the the sea-surface statistics displays a less systematic dependence on the wind speed, with differences in the range ∼13 to ∼18%. The ρ changes due to the light polarization and the variance of the waves slope become more relevant at sky-viewing geometries respectively lower and higher than 40° with respect to the zenith. An overall compensation of positive and negative offsets due to light polarization is finally documented when considering different sun elevations. These results address additional investigations which, by combining the modeling and experimental components of marine optics, better evaluate specific measurement protocols for collecting above-water radiometric data in the field.

  2. Effects of light polarization and waves slope statistics on the reflectance factor of the sea surface.

    PubMed

    D'Alimonte, Davide; Kajiyama, Tamito

    2016-04-18

    Above-water radiometry depends on estimates of the reflectance factor ρ of the sea surface to compute the in situ water-leaving radiance. The Monte Carlo code for ocean color simulations MOX is used in this study to analyze the effect of different environmental components on ρ values. A first aspect is examining the reflectance factor without and by accounting for the sky-radiance polarization. The influence of the sea-surface statistics at discrete grid points is then considered by presenting a new scheme to define the variance of the waves slope. Results at different sun elevations and sensor orientations indicate that the light polarization effect on ρ simulations reduces from ∼17 to ∼10% when the wind speed increases from 0 to 14m s-1. An opposite tendency characterizes the modeling of the sea-surface slope variance, with ρ differences up to ∼12% at a wind speed of 10m s-1. The joint effect of polarization and the the sea-surface statistics displays a less systematic dependence on the wind speed, with differences in the range ∼13 to ∼18%. The ρ changes due to the light polarization and the variance of the waves slope become more relevant at sky-viewing geometries respectively lower and higher than 40° with respect to the zenith. An overall compensation of positive and negative offsets due to light polarization is finally documented when considering different sun elevations. These results address additional investigations which, by combining the modeling and experimental components of marine optics, better evaluate specific measurement protocols for collecting above-water radiometric data in the field. PMID:27137234

  3. Climate change scenarios and the effect of sea-level rise for Estonia

    NASA Astrophysics Data System (ADS)

    Kont, Are; Jaagus, Jaak; Aunap, Raivo

    2003-03-01

    Climate warming due to the enhanced greenhouse effect is expected to have a significant impact on natural environment and human activity in high latitudes. Mostly, it should have a positive effect on human activity. The main threats in Estonia that could be connected with sea-level rise are the flooding of coastal areas, erosion of sandy beaches and the destruction of harbour constructions. Possible climate change and its negative impacts in the coastal regions of Estonia are estimated in this paper. Climate change scenarios for Estonia were generated using a Model for the Assessment of Greenhouse-gas Induced Climate Change (MAGICC) and a regional climate change database—SCENanario GENerator (SCENGEN). Three alternative emission scenarios were combined with data from 14 general circulation model experiments. Climate change scenarios for the year 2100 indicate a significant increase in air temperature (by 2.3-4.5 °C) and precipitation (by 5-30%) in Estonia. The highest increase is expected to take place during winter and the lowest increase in summer. Due to a long coastline (3794 km) and extensive low-lying coastal areas, global climate change through sea-level rise will strongly affect the territory of Estonia. A number of valuable natural ecosystems will be in danger. These include both marine and terrestrial systems containing rare plant communities and suitable breeding places for birds. Most sandy beaches high in recreational value will disappear. However, isostatic land uplift and the location of coastal settlements at a distance from the present coastline reduce the rate of risk. Seven case study areas characterising all the shore types of Estonia have been selected for sea-level rise vulnerability and adaptation assessment. Results and estimates of vulnerability to 1.0-m sea-level rise by 2100 are presented in this paper. This is the maximum scenario according to which the actually estimated relative sea-level rise would vary from 0.9 m (SW Estonia) to 0

  4. Understanding the Effects of Sea-Level Rise on Coastal Wetlands: The Human Dimension

    NASA Astrophysics Data System (ADS)

    Reed, Denise

    2010-05-01

    In the 21st century coastal systems are subject to the pressures of centuries of population growth and resource exploitation. In 2003, in the US approximately 153 million people (53 percent of the population) lived in coastal counties, an increase of 33 million people since 1980 and this is expected to increase by approximately 7 million by the year 2008. Eight of the world's top ten largest cities are located at the coast, 44 % of the world's population (more people than inhabited the entire globe in 1950) live within 150 km of the coast and in 2001 over half the world's population lived within 200 km of a coastline. . Increased population density at the coasts often brings pollution and habitat degradation - decreasing the value of many of the resources that initially attract the coastal development - and it also means the effect of sea-level rise on coastal geomorphic systems must be seen in the context of additional human pressures. For global sea-level debate centers on the magnitude and rate of the rise around most of the world; the exception being those areas still experiencing falling sea-levels due to isostatic rebound. Many coastal island states are clearly vulnerable. While the ‘lurid and misleading maps' of the 1980's used by many to indicate areas to be flooded by rising seas in the future, have been replaced by more considered discussion of the response of coastal dynamics to rising seas there is still considerable debate about the amount of sea-level rise shorelines will experience in the 21st century. For coastal wetlands four main sets of physical factors - fine sediment regime; tidal conditions; coastal configuration; and relative sea-level change - define the geomorphic context for coastal marsh development and survival during the 21st century. Each of these factors is influenced by changes in climate and human alterations to coastal and inshore environments. In turn changes in sediment dynamics are mediated by both physical forcing and biotic

  5. Effect of air-sea coupling on the frequency distribution of intense tropical cyclones over the northwestern Pacific

    NASA Astrophysics Data System (ADS)

    Ogata, Tomomichi; Mizuta, Ryo; Adachi, Yukimasa; Murakami, Hiroyuki; Ose, Tomoaki

    2015-12-01

    Effect of air-sea coupling on the frequency distribution of intense tropical cyclones (TCs) over the northwestern Pacific (NWP) region is investigated using an atmosphere and ocean coupled general circulation model (AOGCM). Monthly varying flux adjustment enables AOGCM to simulate both subseasonal air-sea interaction and realistic seasonal to interannual sea surface temperature (SST) variability. The maximum of intense TC distribution around 20-30°N in the AGCM shifts equatorward in the AOGCM due to the air-sea coupling. Hence, AOGCM reduces northward intense TC distribution bias seen in AGCM. Over the NWP, AOGCM-simulated SST variability is large around 20-30°N where the warm mixed layer becomes shallower rapidly. Active entrainment from subsurface water over this region causes stronger SST cooling, and hence, TC intensity decreases. These results suggest that air-sea coupling characterized by subsurface oceanic condition causes more realistic distribution of intense TCs over the NWP.

  6. Effects of carbon dioxide sequestration on California margin deep-sea foraminiferal assemblages

    SciTech Connect

    Ricketts, Erin R.; Kennett, James P.; Hill, Tessa M.; Barry, James P.

    2009-09-01

    Abstract Deep-sea sequestration of CO2 is being considered as a possible mitigation tool to decrease atmospheric CO2 concentrations and its associated negative effects. This study investigated potential effects of liquid carbon dioxide (CO2) injection on deep-sea foraminiferal assemblages. Foraminifera are ideal for this ecological impact investigation because of differing test composition (calcareous and non-calcareous) and thickness, and diverse epifaunal and infaunal depth preferences. The experiment was conducted on August-September 2003, at 3600 m off the coast of Monterey Bay, California, aboard the R/V Western Flyer using the ROV Tiburon. The pH of the site was monitored throughout the experiment. Sediment push-cores were collected (both from the experimental and control sites) and stained to distinguish live (stained) from dead (unstained) individuals. Effects of CO2 injection on assemblages have been tracked both vertically (to 10 cm depth below sea floor) and horizontally (up to 10 m from CO2 injection sites), as well as between live and dead individuals. Within corrals (containing the injected CO2) and their underlying sediments, severe pH changes (near 4.0 units) were recorded. This compares with a record of small average reductions in ocean pH (-0.05 units) combined with large episodic excursions (-1.7 units) over the experimental area due to the injection of CO2. Exposure to this gradient of low pH caused increased mortality and dissolution of calcareous forms within corrals, as far as 5 m from the injection site, and to at least 10 cm depth in the sediments. This experiment revealed several major effects of CO2 injection on foraminiferal assemblages in surficial sediments: 1) total number of foraminifera in a sample decreases; 2) foraminiferal species richness decreases in both stained and unstained specimens; and 3) relative percentage of stained (live) forms in the remaining tests increases. Down-core trends (to 10 cm below sea floor) have revealed

  7. Wind effect on the Atlantic meridional overturning circulation via sea ice and vertical diffusion

    NASA Astrophysics Data System (ADS)

    Yang, Haijun; Wang, Kun; Dai, Haijin; Wang, Yuxing; Li, Qing

    2016-06-01

    Effects of wind and fresh water on the Atlantic meridional overturning circulation (AMOC) are investigated using a fully coupled climate model. The AMOC can change significantly when perturbed by either wind stress or freshwater flux in the North Atlantic. This study focuses on wind stress effect. Our model results show that the wind forcing is crucial in maintaining the AMOC. Reducing wind forcing over the ocean can cause immediately weakening of the vertical salinity diffusion and convection in the mid-high latitudes Atlantic, resulting in an enhancement of vertical salinity stratification that restrains the deep water formation there, triggering a slowdown of the thermohaline circulation. As the thermohaline circulation weakens, the sea ice expands southward and melts, providing the upper ocean with fresh water that weakens the thermohaline circulation further. The wind perturbation experiments suggest a positive feedback between sea-ice and thermohaline circulation strength, which can eventually result in a complete shutdown of the AMOC. This study also suggests that sea-ice variability may be also important to the natural AMOC variability on decadal and longer timescales.

  8. The effects of two analgesic regimes on behavior after abdominal surgery in Steller sea lions.

    PubMed

    Walker, Kristen A; Horning, Markus; Mellish, Jo-Ann E; Weary, Daniel M

    2011-10-01

    This study examined the effects of two non-steroidal anti-inflammatory drug (NSAID) treatment protocols on the behavioral responses of juvenile Steller sea lions after abdominal surgery. Sea lions were randomly assigned to one of two treatments designed to control post-operative pain. The flunixin group (n=6) received flunixin meglumine (1mg/kg) administered as a single intramuscular (IM) injection before extubation from surgery. The carprofen group (n=5) received carprofen (4.4 mg/kg) as an IM injection before extubation, then orally at 24, 48 and 72 h after surgery. Seven behaviors related to post-operative pain were monitored by observers, blinded to treatment, for a total of 10 days (3 days pre-, day of surgery, and 6 days post-surgery). All seven behaviors changed after surgery regardless of NSAID treatment, two of which returned to baseline within 6 days of surgery. Only one behavior was mildly affected by analgesic treatment: sea lions in the carprofen group tended to spend less time lying down in Days 1-3 following surgery (i.e., the days which they received oral carprofen). These results suggested that neither treatment, at the dose administered, was effective in controlling pain in the days following this surgery.

  9. Effects of different microbes on fermenting feed for sea cucumber ( Apostichopus japonicus)

    NASA Astrophysics Data System (ADS)

    Jiang, Yan; Wang, Yingeng; Mai, Kangsen; Zhang, Zheng; Liao, Meijie; Rong, Xiaojun

    2015-10-01

    The effects of different microbes on fermenting feed for sea cucumber ( Apostichopus japonicus) were compared to select the optimal fermentation strain in this study. Saccharomgces cerevisae, Candida utilis, Bacillus subtilis and Geotrichum candidum were independently added into the experimental compound feed, while only saline was mixed with the control feed. The fermentation treatments were inoculated with 10% seed solution under the condition of 25°C and 70% water content, which lasted for 5 days to elucidate the optimal microbe strain for fermenting effect. Physicochemical indexes and sensorial characteristics were measured per day during the fermentation. The indexes included dry matter recovery (DMR), crude protein (CP), the percentage of amino acid nitrogen to total nitrogen (AA-N/tN), the percentage of ammonia nitrogen to total nitrogen (NH3-N/tN), and the ratio of fermentation strains and vibrios to the total microbes, color, smell and viscosity. The results showed that DMR, CP and AA-N/tN of the S. cerevisae group reached the highest level on day 3, but the ratio of fermentation strain was second to C. utilis group. In addition, its NH3-N/tN and the ratio of vibrios were maintained at low levels, and the sensory evaluation score including smell, color and viscosity was the highest in S. cerevisae group on day 3. Therefore, S. cerevisae could be the optimal strain for the feed fermentation for sea cucumber. This research developed a new production method of fermentation feed for sea cucumber.

  10. Effect of thermal treatment on magnetic and dielectric response of SrM hexaferrites obtained by hydrothermal synthesis

    NASA Astrophysics Data System (ADS)

    Hilczer, Andrzej; Andrzejewski, Bartłomiej; Markiewicz, Ewa; Kowalska, Katarzyna; Pietraszko, Adam

    2014-11-01

    Electric, dielectric and magnetic properties of SrFe12O19 hexaferrite ceramics obtained from hydrothermally synthesized single-phase nanopowders were studied in wide temperature range. The effect of space charge polarization, related to highly conducting grains with poor conducting grain boundaries, was found to be apparent at high temperatures and at low frequencies. The activation energy of relaxation of the (Fe3+-Fe2+) dipoles in low conducting grain boundary regions was found to amount to 0.20 eV for non-annealed ceramics and to increase to 0.32 eV after thermal treatment. The temperature and frequency dependences of the dielectric permittivity for non-annealed and annealed SrFe12O19 ceramics were found to be correlated with respective dependences of the electric conductivity. We relate the observed increase in the saturation magnetization after annealing to an increase in coherent spin rotation in greater grains, which are however still below the critical single-domain size.

  11. Some physical effects of reaction rate on PbS thin films obtained by chemical bath deposition

    NASA Astrophysics Data System (ADS)

    Altıokka, Barış; Baykul, Mevlana Celalettin; Altıokka, Mehmet Rıza

    2013-12-01

    Thin films of polycrystalline lead sulfide (PbS) have been deposited on glass substrates at 303±1 K using chemical bath deposition (CBD). The precipitation of PbS on solid surfaces under four different reaction conditions was performed using a sodium sulfite (Na2SO3) compound as an inhibitor. The kinetics model for the reaction between Pb2+ and S2- was developed according to the amounts of Pb2+ concentrations measured by atomic absorption spectroscopy (AAS) during the precipitation of PbS. The surface morphologies of PbS thin films were studied with a Scanning Electron Microscope (SEM). It was found that the precipitation rate effects the formation of pinhole. To obtain a good quality of thin films the optimum concentration of lead nitrate (Pb(NO3)2), sodium hydroxide (NaOH), thiourea (CS(NH2)2) and Na2SO3 in the final solution was determined to be 0.0089, 0.1460, 0.510 and 0.00023 M, respectively. The film structures were characterized by X-ray diffractometer (XRD). The XRD results showed that the films formed galena cubic structures which represent the natural mineral of PbS. The crystallite sizes of the films were found to be between 23 and 37 nm.

  12. Effect of rising sea level on runoff and groundwater discharge to coastal ecosystems

    USGS Publications Warehouse

    Nuttle, W.K.; Portnoy, J.W.

    1992-01-01

    Rising sea level can cause an increase in surface runoff from coastal areas by raising the watertable and thus increasing the incidence of saturated soil conditions in low-lying areas. As surface runoff increases, less rainfall will infiltrate into the ground and groundwater discharge to the coast will decrease. The link between sea level rise and runoff is critically dependent on the sensitivity of surface runoff to changes in the elevation of the watertable. A significant relation between the two is demonstrated for a coastal watershed on Cape Cod, where it is estimated that a 10 cm rise in the watertable will increase surface runoff by 70% and decrease groundwater discharge by 20%. Effects on near-shore ecosystems include changes in nutrient fluxes and in the salinity of the sediments.

  13. Effects of sea-level rise on barrier island groundwater system dynamics: ecohydrological implications

    USGS Publications Warehouse

    Masterson, John P.; Fienen, Michael N.; Thieler, E. Robert; Gesch, Dean B.; Gutierrez, Benjamin T.; Plant, Nathaniel G.

    2014-01-01

    We used a numerical model to investigate how a barrier island groundwater system responds to increases of up to 60 cm in sea level. We found that a sea-level rise of 20 cm leads to substantial changes in the depth of the water table and the extent and depth of saltwater intrusion, which are key determinants in the establishment, distribution and succession of vegetation assemblages and habitat suitability in barrier islands ecosystems. In our simulations, increases in water-table height in areas with a shallow depth to water (or thin vadose zone) resulted in extensive groundwater inundation of land surface and a thinning of the underlying freshwater lens. We demonstrated the interdependence of the groundwater response to island morphology by evaluating changes at three sites. This interdependence can have a profound effect on ecosystem composition in these fragile coastal landscapes under long-term changing climatic conditions.

  14. Mercury speciation analysis in sea water by solid phase microextraction?gas chromatography?inductively coupled plasma mass spectrometry using ethyl and propyl derivatization. Matrix effects evaluation

    NASA Astrophysics Data System (ADS)

    Bravo-Sánchez, Luis R.; Ruiz Encinar, Jorge; Fidalgo Martínez, José I.; Sanz-Medel, Alfredo

    2004-01-01

    An approach to the speciation analysis of mercury in sea-water samples at sub-ppt levels by means of the hyphenation of solid phase microextraction to gas chromatography-inductively coupled plasma mass spectrometry was developed. Blank values turned out to be the limiting factor for lower detection limits of inorganic mercury. Thus, all the reagents were thoroughly cleaned using laboratory made microcolumns packed with 8-hydroxyquinoline on TSK gel. Sodium tetrapropylborate (NaBPr 4) synthesized for the purpose of derivatization of the mercury species resulted in better analytical performances of the method, probably due to lower mercury contamination, than commercial sodium tetraethylborate (NaBEt 4). Detection limits down to a few picogram per liter for both mercury and methylmercury were obtained using NaBPr 4. The high salt content of sea-water samples was responsible for strong matrix effects, which were overcome by using standards additions to the samples. The validation of the methodology was carried out by direct comparison of the results for inorganic mercury with those obtained using a flow injection system followed by preconcentration/trapping of the species and its detection by atomic absorption spectrometry. The proposed method was applied to the determination of mercury and methylmercury in coastal sea-water samples from Gijón (Asturias, Spain) and results obtained are discussed in the light of the butyltin levels previously determined in the same area.

  15. The distribution of deep-sea sponge aggregations in the North Atlantic and implications for their effective spatial management

    NASA Astrophysics Data System (ADS)

    Howell, Kerry-Louise; Piechaud, Nils; Downie, Anna-Leena; Kenny, Andrew

    2016-09-01

    Sponge aggregations have been recognised as key component of shallow benthic ecosystems providing several important functional roles including habitat building and nutrient recycling. Within the deep-sea ecosystem, sponge aggregations may be extensive and available evidence suggests they may also play important functional roles, however data on their ecology, extent and distribution in the North Atlantic is lacking, hampering conservation efforts. In this study, we used Maximum Entropy Modelling and presence data for two deep-sea sponge aggregation types, Pheronema carpenteri aggregations and ostur aggregations dominated by geodid sponges, to address the following questions: 1) What environmental factors drive the broad-scale distribution of these selected sponge grounds? 2) What is the predicted distribution of these grounds in the northern North Atlantic, Norwegian and Barents Sea? 3) How are these sponge grounds distributed between Exclusive Economic Zones (EEZs) and High Seas areas? 4) What percentage of these grounds in High Seas areas are protected by the current High Seas MPA network? Our results suggest that silicate concentration, temperature, depth and amount of particulate organic carbon are the most important drivers of sponge distribution. Most of the sponge grounds are located within national EEZs rather than in the High Seas. Coordinated conservation planning between nations with significant areas of sponge grounds such as Iceland, Greenland and Faroes (Denmark), Norway (coastal Norway and Svalbard), Portugal and the UK, should be implemented in order to effectively manage these communities in view of the increasing level of human activity within the deep-sea environment.

  16. No observed effect of ocean acidification on nitrogen biogeochemistry in a summer Baltic Sea plankton community

    NASA Astrophysics Data System (ADS)

    Paul, Allanah J.; Achterberg, Eric P.; Bach, Lennart T.; Boxhammer, Tim; Czerny, Jan; Haunost, Mathias; Schulz, Kai-Georg; Stuhr, Annegret; Riebesell, Ulf

    2016-07-01

    Nitrogen fixation by filamentous cyanobacteria supplies significant amounts of new nitrogen (N) to the Baltic Sea. This balances N loss processes such as denitrification and anammox, and forms an important N source supporting primary and secondary production in N-limited post-spring bloom plankton communities. Laboratory studies suggest that filamentous diazotrophic cyanobacteria growth and N2-fixation rates are sensitive to ocean acidification, with potential implications for new N supply to the Baltic Sea. In this study, our aim was to assess the effect of ocean acidification on diazotroph growth and activity as well as the contribution of diazotrophically fixed N to N supply in a natural plankton assemblage. We enclosed a natural plankton community in a summer season in the Baltic Sea near the entrance to the Gulf of Finland in six large-scale mesocosms (volume ˜ 55 m3) and manipulated fCO2 over a range relevant for projected ocean acidification by the end of this century (average treatment fCO2: 365-1231 µatm). The direct response of diazotroph growth and activity was followed in the mesocosms over a 47 day study period during N-limited growth in the summer plankton community. Diazotrophic filamentous cyanobacteria abundance throughout the study period and N2-fixation rates (determined only until day 21 due to subsequent use of contaminated commercial 15N-N2 gas stocks) remained low. Thus estimated new N inputs from diazotrophy were too low to relieve N limitation and stimulate a summer phytoplankton bloom. Instead, regeneration of organic N sources likely sustained growth in the plankton community. We could not detect significant CO2-related differences in neither inorganic nor organic N pool sizes, or particulate matter N : P stoichiometry. Additionally, no significant effect of elevated CO2 on diazotroph activity was observed. Therefore, ocean acidification had no observable impact on N cycling or biogeochemistry in this N-limited, post-spring bloom

  17. Accounting for the effect of TDS and NCG on Salton Sea reservoir response

    SciTech Connect

    Butler, Steven J.

    1992-01-01

    The Salton Sea reservoir, located in Imperial County, Ca., is unique in several ways from most liquid-dominated geothermal reservoirs that have been developed to date. One of these differences is the presence of hyper-saline brines containing up to 28% TDS (Total Dissolved Solids) and up to 0.2% NCG (Non-Condensible Gas). A simple material and energy balance model has been developed to study the effect of TDS and NCG on Salton Sea reservoir response. This study demonstrated that during the development of a two-phase system the partitioning of the NCG into the vapor phase and the consequential concentration of the TDS in the brine drastically alters the reservoir fluid properties. In modeling pressure depletion of hyper-saline reservoirs, such as the Salton Sea, these changes in reservoir fluid composition were shown to seriously affect the simulation results. As a result of these findings, a compositional fluid property package was developed using published data on H{sub 2}O-CO{sub 2}-NaCl mixtures. This fluid property package was then incorporated into the simulation program used by Unocal. Validation of the fluid property package in this simulation program was made using measured reservoir temperature, surface enthalpy, and surface flash data. The development of a compositional simulation program for geothermal applications has advanced our ability to study depletion mechanisms that are sensitive to compositional changes. This program is currently being used to study the effect of injection and steam cap development on long term operations and to develop a field model of the Salton Sea reservoir.

  18. No observed effect of ocean acidification on nitrogen biogeochemistry in a summer Baltic Sea plankton community

    NASA Astrophysics Data System (ADS)

    Paul, A. J.; Achterberg, E. P.; Bach, L. T.; Boxhammer, T.; Czerny, J.; Haunost, M.; Schulz, K.-G.; Stuhr, A.; Riebesell, U.

    2015-10-01

    Nitrogen fixation by filamentous cyanobacteria supplies significant amounts of new nitrogen (N) to the Baltic Sea. This balances N loss processes such as denitrification and anammox and forms an important N source supporting primary and secondary production in N-limited post-spring bloom plankton communities. Laboratory studies suggest that filamentous diazotrophic cyanobacteria growth and N2-fixation rates are sensitive to ocean acidification with potential implications for new N supply to the Baltic Sea. In this study, our aim was to assess the effect of ocean acidification on diazotroph growth and activity as well as the contribution of diazotrophically-fixed N to N supply in a natural plankton assemblage. We enclosed a natural plankton community in a summer season in the Baltic Sea near the entrance to the Gulf of Finland in six large-scale mesocosms (volume ~ 55 m3) and manipulated fCO2 over a range relevant for projected ocean acidification by the end of this century (average treatment fCO2: 365-1231 μatm). The direct response of diazotroph growth and activity was followed in the mesocosms over a 47 day study period during N-limited growth in the summer plankton community. Diazotrophic filamentous cyanobacteria abundance throughout the study period and N2-fixation rates (determined only until day 21 due to subsequent use of contaminated commercial 15N-N2 gas stocks) remained low. Thus estimated new N inputs from diazotrophy were too low to relieve N limitation and stimulate a summer phytoplankton bloom. Instead regeneration of organic N sources likely sustained growth in the plankton community. We could not detect significant CO2-related differences in inorganic or organic N pools sizes, or particulate matter N : P stoichiometry. Additionally, no significant effect of elevated CO2 on diazotroph activity was observed. Therefore, ocean acidification had no observable impact on N cycling or biogeochemistry in this N-limited, post-spring bloom plankton

  19. Assessing bio-physical effects of Offshore Wind Farms on the North Sea pelagic ecosystem using a TRIAXUS ROTV

    NASA Astrophysics Data System (ADS)

    Floeter, Jens; Callies, Ulrich; Dudeck, Tim; Eckhardt, André; Gloe, Dominik; Hufnagl, Marc; Ludewig, Elke; Möller, Klas O.; North, Ryan P.; Pohlmann, Thomas; Riethmüller, Rolf; Temming, Axel; van Beusekom, Justus; Walter, Bettina; Möllmann, Christian

    2015-04-01

    The effects of Offshore Wind Farms (OWFs) on marine ecosystem functioning are largely unknown. OWF foundations may lead to locally increased turbulence levels in the pelagic zone, and as turbines deflect the wind field, the extraction of energy may induce up- and downwelling dipoles in the water column. As a consequence, upwelling cells and locally increased vertical mixing will likely transport nutrients and phytoplankton into the nutrient-depleted surface layer of the stratified water column in summer. Subsequently, locally enhanced primary production could potentially be channelled to higher trophic levels and may lead to an increased habitat quality for demersal & pelagic fish. Here, we present field measurements that allow us to assess the bio-physical effects of OWFs on the North Sea pelagic ecosystem. Data were obtained using a TRIAXUS (a remotely operated towed vehicle, ROTV) during a survey in summer 2014, which included three OWFs located in water depths between 20m and 40m. TRIAXUS is designed to record high-frequency synoptic measurements of biological and physical oceanographic properties. The instrument is equipped with CTD, oxygen, light and fluorescence sensors as well as a Laser Optical Plankton Counter (LOPC) and a Video Plankton Recorder (VPR). Fisheries hydroacoustic and ADCP data were recorded in parallel. Hydrodynamic modelling supported the analysis by backtracking the drift routes of water bodies from which nutrient contents were analysed. To isolate the OWF effects from natural variability in the bio-physical properties of the German Bight, we also analysed spatially and seasonally similar SCANFISH transect data from pre-OWF years (2010, 2011). The survey provided first insights into the potential bio-physical effects of OWFs on the North Sea pelagic ecosystem, e.g., small scale areas of increased mixing, local upwelling and changes in the magnitude of the surface layer with distinct phytoplankton discontinuities.

  20. Effects of recent decreases in arctic sea ice on an ice-associated marine bird

    NASA Astrophysics Data System (ADS)

    Divoky, George J.; Lukacs, Paul M.; Druckenmiller, Matthew L.

    2015-08-01

    Recent major reductions in summer arctic sea ice extent could be expected to be affecting the distributions and life histories of arctic marine biota adapted to living adjacent to sea ice. Of major concern are the effects of ice reductions, and associated increasing SST, on the most abundant forage fish in the Arctic, Arctic cod (Boreogadus saida), the primary prey for the region's upper trophic level marine predators. The black guillemot (Cepphus grylle mandtii) is an ice-obligate diving seabird specializing in feeding on Arctic cod and has been studied annually since 1975 at a breeding colony in the western Beaufort Sea. The data set is one of the few allowing assessment of the response of an upper trophic marine predator to recent decadal changes in the region's cryosphere. Analysis of oceanographic conditions north of the colony from 1975 to 2012 for the annual period when parents provision young (mid-July to early September), found no major regime shifts in ice extent or SST until the late 1990s with major decreases in ice and increases in SST in the first decade of the 21st Century. We examined decadal variation in late summer oceanographic conditions, nestling diet and success, and overwinter adult survival, comparing a historical period (1975-1984) with a recent (2003-2012) one. In the historical period sea ice retreated an average of 1.8 km per day from 15 July to 1 September to an average distance of 95.8 km from the colony, while in the recent period ice retreat averaged 9.8 km per day to an average distance of 506.9 km for the same time period. SST adjacent to the island increased an average of 2.9 °C between the two periods. While Arctic cod comprised over 95% of the prey provided to nestlings in the historical period, in the recent period 80% of the years had seasonal decreases, with Arctic cod decreasing to <5% of the nestling diet, and nearshore demersals, primarily sculpin (Cottidae), comprising the majority of the diet. A five-fold increase in

  1. Effects of surface current-wind interaction in an eddy-rich general ocean circulation simulation of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Dietze, Heiner; Löptien, Ulrike

    2016-08-01

    Deoxygenation in the Baltic Sea endangers fish yields and favours noxious algal blooms. Yet, vertical transport processes ventilating the oxygen-deprived waters at depth and replenishing nutrient-deprived surface waters (thereby fuelling export of organic matter to depth) are not comprehensively understood. Here, we investigate the effects of the interaction between surface currents and winds on upwelling in an eddy-rich general ocean circulation model of the Baltic Sea. Contrary to expectations we find that accounting for current-wind effects inhibits the overall vertical exchange between oxygenated surface waters and oxygen-deprived water at depth. At major upwelling sites, however (e.g. off the southern coast of Sweden and Finland) the reverse holds: the interaction between topographically steered surface currents with winds blowing over the sea results in a climatological sea surface temperature cooling of 0.5 K. This implies that current-wind effects drive substantial local upwelling of cold and nutrient-replete waters.

  2. Proceedings of a workshop on cetaceans and sea turtles in the Gulf of Mexico: study planning for effects of Outer Continental Shelf development

    SciTech Connect

    Keller, C.E.; Adams, J.K.

    1983-02-01

    The purpose of the workshop was to assemble scientists knowledgeable about cetaceans, sea turtles, and the Gulf of Mexico to discuss the potential impacts of offshore oil and gas development on these animals and make recommendations for future research. The workshop began with brief presentations about the environment of the Gulf of Mexico and the cetaceans and sea turtles found there, and a review of petroleum effects on these animals. The following points were then discussed: (1) ways in which cetaceans and sea turtles have been or could be affected, either directly or indirectly by activities and events associated with offshore oil and gas development were identified; (2) the types and specificity of data needed to predict, detect, and mitigate possible adverse effects were identified; (3) the advantages and disadvatages of various methods that might be used to obtain needed data were discussed; and (4) specific research and monitoring programs that would be required to obtain needed data, including the necessary expertise, level of effort, equipment, and facilities were identified.

  3. The effects of time compositing on obtaining clear-sky coverage for infrared temperature and moisture profiling from geosynchronous orbit

    NASA Technical Reports Server (NTRS)

    Shenk, William E.; Hope, William A.

    1994-01-01

    The impact of time compositing on infrared profiling from geosynchronous orbit was evaluated for two convective outbreak cases. Time compositing is the accumulation of the data from several successive images taken at short intervals to provide a single field of measurements with the temporal resolution equal to the time to take all of the images. This is especially effective when the variability of the measurements is slow compared to the image interval. Time compositing should be able to reduce the interference of clouds for infrared measurments since clouds move and change. The convective outbreak cases were on 4 and 21 May 1990 over the eastern Midwest and southeastern United States, respectively. Geostationary Operational Environmental (GOES) Satellite imagery was used to outline clear areas at hourly intervals by two independent analysts. Time compositing was done every 3 h (1330-1530 UTC; 1630-1830 UTC) and over the full 5-h period. For both cases, a significant increase in coverage was measured with each 3-h compositing (about a factor of 2) and a further increase over the full period (approximately a factor of 3). The increase was especially useful in areas of broken cloud cover where large gaps between potential profiling areas on each image were reduced. To provide information on measurement variability over local areas, the regions where the clear-area analyses were done were subdivided into 0.5 deg latitude-longitude boxes, and if some portion of each box was clear, it was assumed that at least one profile could be obtained within the box. In the largest clear areas, at least some portion was clear every hour. Even in the cloudier regions, multiple clear looks possible during the entire period.

  4. Comparing the effects of two neurotoxins in cortical astrocytes obtained from rats of different ages: involvement of oxidative damage.

    PubMed

    Alarcón-Aguilar, Adriana; González-Puertos, Viridiana Yazmín; Luna-López, Armando; López-Macay, Ambar; Morán, Julio; Santamaría, Abel; Königsberg, Mina

    2014-02-01

    Oxidative stress has been recognized as a potential mediator of cell death. Astrocytes play an active role in brain physiology responding to harmful stimuli by activating astrogliosis, which in turn has been associated either with survival or degenerative events. The characterization of the mechanistic actions exerted by different toxins in astrocytes is essential to understand the brain function and pathology. As age plays a critical role in degenerative processes, the aim of this study was to determine whether the administration of equimolar concentrations of two neurotoxins evoking different toxic patterns can induce differential effects on primary astrocytes obtained either from newborn or adult rats, with particular emphasis on those events linked to oxidative stress as a potential source of damage. Primary cortical astrocyte cultures derived from rat brains were exposed to 1-methyl-4-phenylpyridinium (MPP+) or beta-amyloid peptide (β-amyloid). Mitochondrial functionality and cell viability were determined as physiological parameters, whereas lipid and protein oxidation were used as markers of oxidative damage. The results of these experiments pointed towards a higher vulnerability to MPP + over β-amyloid, on most of the tested markers. Hence, in order to allow a comprehensive evaluation of astrocytic responses against MPP + intoxication, a third astrocyte group was included for dose-response experiments: astrocytes derived from aged rats. The present data indicate that the differences associated with age were mainly found in astrocytes exposed to MPP + (25 and 50 μM) at 1-h treatment. Results are discussed in terms of the differential mechanisms involved in each model.

  5. Indirect effects of sea otters on rockfish (Sebastes spp.) in giant kelp forests.

    PubMed

    Markel, Russell W; Shurin, Jonathan B

    2015-11-01

    Sea otters are a classic example of a predator controlling ecosystem productivity through cascading effects on basal, habitat-forming kelp species. However, their indirect effects on other kelp-associated taxa like fishes are poorly understood. We examined the effects of sea otter (Enhydra lutris) reintroduction along the west coast of Vancouver Island, Canada on giant kelp (Macrocystis pyrifera) distributions and the trophic niches and growth of two common kelp forest fishes, black (Sebastes melanops) and copper (S. caurinus) rockfishes. We sampled 47 kelp forests, and found that red sea urchins (Strongylocentrotus franciscanus) were eliminated in the presence of otters, and that kelp forests were 3.7 times deeper and 18.8 times larger. Despite order-of-magnitude differences in kelp forest size, adult black and copper rockfishes contained less kelp-derived carbon in their tissues (as measured by stable isotopes of C and N) in regions with otters. Adults of both species had higher mean trophic positions in the presence of otters, indicating more frequent consumption of higher trophic level prey such as fishes. Smaller trophic niche space of rockfishes in the presence of otters indicated a higher degree of trophic specialization. Juvenile black rockfishes rapidly shifted to higher kelp-carbon contents, trophic positions, and body condition factors after settling in kelp forests. The relationships of growth to length, percentage of kelp carbon, and trophic position varied between the two regions, indicating that potential effects of kelp forest size on trophic ontogeny may also affect individual performance. Our results provide evidence that the indirect effects of otters on rockfishes arise largely through the creation of habitat for fishes and other prey rather than a direct trophic connection through invertebrates or other consumers of kelp productivity.

  6. Indirect effects of sea otters on rockfish (Sebastes spp.) in giant kelp forests.

    PubMed

    Markel, Russell W; Shurin, Jonathan B

    2015-11-01

    Sea otters are a classic example of a predator controlling ecosystem productivity through cascading effects on basal, habitat-forming kelp species. However, their indirect effects on other kelp-associated taxa like fishes are poorly understood. We examined the effects of sea otter (Enhydra lutris) reintroduction along the west coast of Vancouver Island, Canada on giant kelp (Macrocystis pyrifera) distributions and the trophic niches and growth of two common kelp forest fishes, black (Sebastes melanops) and copper (S. caurinus) rockfishes. We sampled 47 kelp forests, and found that red sea urchins (Strongylocentrotus franciscanus) were eliminated in the presence of otters, and that kelp forests were 3.7 times deeper and 18.8 times larger. Despite order-of-magnitude differences in kelp forest size, adult black and copper rockfishes contained less kelp-derived carbon in their tissues (as measured by stable isotopes of C and N) in regions with otters. Adults of both species had higher mean trophic positions in the presence of otters, indicating more frequent consumption of higher trophic level prey such as fishes. Smaller trophic niche space of rockfishes in the presence of otters indicated a higher degree of trophic specialization. Juvenile black rockfishes rapidly shifted to higher kelp-carbon contents, trophic positions, and body condition factors after settling in kelp forests. The relationships of growth to length, percentage of kelp carbon, and trophic position varied between the two regions, indicating that potential effects of kelp forest size on trophic ontogeny may also affect individual performance. Our results provide evidence that the indirect effects of otters on rockfishes arise largely through the creation of habitat for fishes and other prey rather than a direct trophic connection through invertebrates or other consumers of kelp productivity. PMID:27070008

  7. Effects of dendritic core-shell glycoarchitectures on primary mesenchymal stem cells and osteoblasts obtained from different human donors.

    PubMed

    Lautenschläger, Stefan; Striegler, Christin; Dakischew, Olga; Schütz, Iris; Szalay, Gabor; Schnettler, Reinhard; Heiß, Christian; Appelhans, Dietmar; Lips, Katrin S

    2015-01-01

    The biological impact of novel nano-scaled drug delivery vehicles in highly topical therapies of bone diseases have to be investigated in vitro before starting in vivo trials. Highly desired features for these materials are a good cellular uptake, large transport capacity for drugs and a good bio-compatibility. Essentially the latter has to be addressed as first point on the agenda. We present a study on the biological interaction of maltose-modified poly(ethyleneimine) (PEI-Mal) on primary human mesenchymal stem cell, harvested from reaming debris (rdMSC) and osteoblasts obtained from four different male donors. PEI-Mal-nanoparticles with two different molecular weights of the PEI core (5000 g/mol for PEI-5k-Mal-B and 25,000 g/mol for PEI-25k-Mal-B) have been administered to both cell lines. As well dose as incubation-time dependent effects and interactions have been researched for concentrations between 1 μg/ml to 1 mg/ml and periods of 24 h up to 28 days. Studies conducted by different methods of microscopy as light microscopy, fluorescence microscopy, transmission-electron-microscopy and quantitative assays (LDH and DC-protein) indicate as well a good cellular uptake of the nanoparticles as a particle- and concentration-dependent impact on the cellular macro- and micro-structure of the rdMSC samples. In all experiments PEI-5k-Mal-B exhibits a superior biocompatibility compared to PEI-25k-Mal-B. At higher concentrations PEI-25k-Mal-B is toxic and induces a directly observable mitochondrial damage. The alkaline phosphatase assay (ALP), has been conducted to check on the possible influence of nanoparticles on the differentiation capabilities of rdMSC to osteoblasts. In addition the production of mineralized matrix has been shown by von-Kossa stained samples. No influence of the nanoparticles on the ALP per cell has been detected. Additionally, for all experiments, results are strongly influenced by a large donor-to-donor variability of the four different rd

  8. The effects of dietary lead on growth, bioaccumulation and antioxidant capacity in sea cucumber, Apostichopus japonicus.

    PubMed

    Wang, Jing; Ren, Tongjun; Han, Yuzhe; Zhao, Yang; Liao, Mingling; Wang, Fuqiang; Jiang, Zhiqiang

    2015-09-01

    Three different diets amended with lead nitrate [Pb(NO3)2] (100, 500 and 1000mg Pb/kg dry weight) and a Pb-free control diet (1.03mg Pb/kg dry weight) were fed to sea cucumber (Apostichopus japonicus) for 30 days. The patterns of Pb accumulation over time were determined in various tissues (body wall, intestine and respiratory tree), as well as growth performance and antioxidant enzymes activities. Pb accumulation in body wall and intestine increased with time in all dietary Pb treatments. When fed the highest Pb diet, the body wall exhibited the greatest Pb burden (16.37mg Pb/kg tissue wet weight), while Pb content in the intestine (2.68mg Pb/kg tissue wet weight) and the respiratory tree (1.78mg Pb/kg tissue wet weight) were lower than Pb content in the body wall by day 30. The body weight gain (BWG), specific growth rate (SGR) and survival rate (SR) had not been affected by 30 days oral administration of Pb supplemented diet. However, the antioxidant enzymes activities [superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px)] of test groups were lower than control group in body wall and malondialdehyde (MDA) concentration in the body wall was opposite after 30 days in sea cucumbers. In summary, this work reports toxic effects in sea cucumber, A. japonicus, after dietary exposure to Pb.

  9. Effect of regulation of the Nile River on the bioproductivity of Southeastern Mediterranean Sea

    SciTech Connect

    Wadia, W.

    1982-01-01

    The Nile River previously brought a large quantity of dissolved nutrients and organic matter into the Southeastern Mediterranean Sea. Since completion of the Aswan hydrocomplex, reduction in the river flow has caused significant change in the distribution of the physico-chemical indices of the sea water as well as in the formation and distribution of the water masses in the region located north of the Nile delta. In recent years changes have been recorded in the dynamics and distribution of water temperature. From 1966 the sediment runoff of the Nile began dropping sharply due not only to reduction in the volume of river water reaching the sea, but also due to a significant reduction in the suspended particles in the flow. This has had a harmful effect on the formation and dynamics of grounds and banks near the delta and north of it. The reproduction of the shrimp in the area has changed significantly in timing and the food supplies for the young shrimp have deteriorated. Shrimp catches in 1966 were half what they had been in 1963. Commercial fishes have also decreased in numbers. Thus all links of the trophic chain have been affected from the phytoplankton to the pelagic and benthic fishes. 11 references, 3 tables.

  10. Cold air outbreaks along a non-frozen sea channel: effects of wind on snow bands

    NASA Astrophysics Data System (ADS)

    Savijärvi, Hannu

    2015-08-01

    Wintertime cold air outbreaks along a non-frozen sea channel or a long lake can become destructive if the related bands of heavy snowfall hit onto land. The forcing for such bands is studied with a 2D numerical model set across an east-west sea channel at 60oN (`Gulf of Finland'), varying the basic geostrophic wind V g. Without any V g opposite coastal land breezes emerge with convergence. This results in a quasi-steady rising motion w max ~ 7.5 cm/s at 600 m in the middle of the gulf, which can force a snow band. During weak V g, the rising motion is reduced but least so for winds from 60o to 80o (~ENE), when modest alongshore bands could exist near the downstream (Estonian) coast. During V g of 4-6 m/s from any direction, the land breezes and rising motions are reduced more effectively, so snow bands are not expected during moderate basic flow. In contrast, during a strong V g of 20-25 m/s from 110o to 120o (~ESE) the land breeze perturbations are intense with w max up to 15-18 cm/s. The induced alongshore bands of heavy snowfall are located in these cases at the sea but quite close to the downstream (Finnish) coast. They can suddenly make a landfall if the basic wind turns clockwise.

  11. Combined effects of the North Atlantic Oscillation and the Arctic Oscillation on sea surface temperature in the Alborán Sea.

    PubMed

    Báez, José C; Gimeno, Luis; Gómez-Gesteira, Moncho; Ferri-Yáñez, Francisco; Real, Raimundo

    2013-01-01

    We explored the possible effects of the North Atlantic Oscillation (NAO) and Arctic Oscillation (AO) on interannual sea surface temperature (SST) variations in the Alborán Sea, both separately and combined. The probability of observing mean annual SST values higher than average was related to NAO and AO values of the previous year. The effect of NAO on SST was negative, while that of AO was positive. The pure effects of NAO and AO on SST are obscuring each other, due to the positive correlation between them. When decomposing SST, NAO and AO in seasonal values, we found that variation in mean annual SST and mean winter SST was significantly related to the mean autumn NAO of the previous year, while mean summer SST was related to mean autumn AO of the previous year. The one year delay in the effect of the NAO and AO on the SST could be partially related to the amount of accumulated snow, as we found a significant correlation between the total snow in the North Alborán watershed for a year with the annual average SST of the subsequent year. A positive AO implies a colder atmosphere in the Polar Regions, which could favour occasional cold waves over the Iberian Peninsula which, when coupled with precipitations favoured by a negative NAO, may result in snow precipitation. This snow may be accumulated in the high peaks and melt down in spring-summer of the following year, which consequently increases the runoff of freshwater to the sea, which in turn causes a diminution of sea surface salinity and density, and blocks the local upwelling of colder water, resulting in a higher SST.

  12. Modelling climate change effects on benthos: Distributional shifts in the North Sea from 2001 to 2099

    NASA Astrophysics Data System (ADS)

    Weinert, Michael; Mathis, Moritz; Kröncke, Ingrid; Neumann, Hermann; Pohlmann, Thomas; Reiss, Henning

    2016-06-01

    In the marine realm, climate change can affect a variety of physico-chemical properties with wide-ranging biological effects, but the knowledge of how climate change affects benthic distributions is limited and mainly restricted to coastal environments. To project the response of benthic species of a shelf sea (North Sea) to the expected climate change, the distributions of 75 marine benthic species were modelled and the spatial changes in distribution were projected for 2099 based on modelled bottom temperature and salinity changes using the IPCC scenario A1B. Mean bottom temperature was projected to increase between 0.15 and 5.4 °C, while mean bottom salinity was projected to moderately increase by 1.7. The spatial changes in species distribution were modelled with Maxent and the direction and extent of these changes were assessed. The results showed a latitudinal northward shift for 64% of the species (maximum 109 km; brittle star Ophiothrix fragilis) and a southward shift for 36% (maximum 101 km; hermit crab Pagurus prideaux and the associated cloak anemone Adamsia carciniopados; 105 km). The relatively low rates of distributional shifts compared to fish or plankton species were probably influenced by the regional topography. The environmental gradients in the central North Sea along the 50 m depth contour might act as a 'barrier', possibly resulting in a compression of distribution range and hampering further shifts to the north. For 49 species this resulted in a habitat loss up to 100%, while only 11 species could benefit from the warming in terms of habitat gain. Particularly the benthic communities of the southern North Sea, where the strongest temperature increase was projected, would be strongly affected by the distributional changes, since key species showed northward shifts and high rates of habitat loss, with potential ramifications for the functioning of the ecosystem.

  13. The Effect of Changes in Polar Sea Ice on Emissions of Marine Aerosols

    NASA Astrophysics Data System (ADS)

    Matrai, P.; Gabric, A. J.

    2015-12-01

    Cloud radiative effects remain a major weakness in our understanding of the climate system and consequently in developing accurate climate projections. This is mainly true for Arctic low-level clouds in their key role of regulating surface energy fluxes which affect the freezing and melting of sea ice. The radiative properties of clouds are strongly dependent on the number concentration of airborne water-soluble particles, known as cloud condensation nuclei (CCN). In the Arctic, the aerosol-cloud-radiation relationship is more complex than elsewhere and the clouds constitute a warming factor for climate, rather than cooling, most of the year. This is due to the semi-permanent ice cover, which raises the albedo of the surface, and the clean Arctic air, which decreases the albedo of the clouds. There has been much discussion on the relative magnitude of the biogenic source of polar CCN: Primary organic marine aerosols and/or sulfate-containing aerosols, derived from marine emissions. Regional field measurements and pan- (Ant)Arctic model simulations don't necessarily agree. Arctic CCN are formed primarily by aggregates of marine organic material and may grow in mass by condensation. Southern Ocean aerosols may be dominated by sulfate particles and organic particles at lower and higher Antarctic latitudes, respectively. The interaction of polar marine microorganisms, seasonality, sea ice cover, presence or absence of sea spray, and atmospheric heterogeneous processes combine to control natural aerosol concentrations and mass, thus modulating the sensitivity of cloud properties, including their reflectivity and the resulting regional radiation budget. We discuss Arctic and Antarctic field and satellite observations and establish a strong and fundamental link between the biology at the ocean/sea ice interface, clouds and climate over polar regions.

  14. Promising dissolution enhancement effect of soluplus on crystallized celecoxib obtained through antisolvent precipitation and high pressure homogenization techniques.

    PubMed

    Homayouni, Alireza; Sadeghi, Fatemeh; Varshosaz, Jaleh; Afrasiabi Garekani, Hadi; Nokhodchi, Ali

    2014-10-01

    Poor solubility and dissolution of hydrophobic drugs have become a major challenge in pharmaceutical development. Drug nanoparticles have been widely accepted to overcome this problem. The aim of this study was to manufacture celecoxib nanoparticles using antisolvent precipitation and high pressure homogenization techniques in the presence of varying concentrations of soluplus(®) as a hydrophilic stabilizer. Antisolvent crystallization followed by freeze drying (CRS-FD) and antisolvent crystallization followed by high pressure homogenization and freeze drying (HPH-FD) were used to obtain celecoxib nanoparticles. The obtained nanoparticles were analyzed in terms of particle size, saturation solubility, morphology (optical and scanning electron microscopy), solid state (DSC, XRPD and FT-IR) and dissolution behavior. The results showed that celecoxib nanoparticle can be obtained when soluplus was added to the crystallization medium. In addition, the results showed that the concentration of soluplus and the method used to prepare nanoparticles can control the size and dissolution of celecoxib. Samples obtained in the presence of 5% soluplus through HPH technique showed an excellent dissolution (90%) within 4min. It is interesting to note that celecoxib samples with high crystallinity showed better dissolution than those celecoxib samples with high amorphous content, although they had the same concentration of soluplus. DSC and XRPD proved that samples obtained via HPH technique are more crystalline than the samples obtained through only antisolvent crystallization technique. PMID:25124835

  15. Steep Gravel Bedload Rating Curves Obtained From Bedload Traps Shift Effective Discharge to Flows Much Higher Than "Bankfull"

    NASA Astrophysics Data System (ADS)

    Bunte, K.; Swingle, K. W.; Abt, S. R.; Cenderelli, D.

    2012-12-01

    Effective discharge (Qeff) is defined as the flow at which the product of flow frequency and bedload transport rates obtains its maximum. Qeff is often reported to correspond with bankfull flow (Qbf), where Qeff approximates the 1.5 year recurrence interval flow (Q1.5). Because it transports the majority of all bedload, Qeff is considered a design flow for stream restoration and flow management. This study investigates the relationship between Qeff and Q1.5 for gravel bedload in high elevation Rocky Mountain streams. Both the flow frequency distribution (FQ = a × Qbin-b) where Qbin is the flow class, and the bedload transport rating curve (QB = c × Qd) can be described by power functions. The product FQ × QB = (a × c × Q(-b + d)) is positive if d + -b >0, and negative if d + -b <0. FQ × QB can only attain a maximum (=Qeff) if either FQ or QB exhibit an inflection point. In snowmelt regimes, low flows prevail for much of the year, while high flows are limited to a few days, and extreme floods are rare. In log-log plotting scale, this distribution causes the longterm flow frequency function FQ to steepen in the vicinity of Q1.5. If the bedload rating curve exponent is small, e.g., = 3 as is typical of Helley-Smith bedload samples, d + -b shifts from >0 to <0, causing FQ × QB to peak, and Qeff to be around Q1.5. For measurements thought to be more representative of actual gravel transport obtained using bedload traps and similar devices, large rating curve exponents d of 6 - 16 are typical. In this case, d + -b remains >0, and FQ × QB reaches its maximum near the largest flow on record (Qeff,BT = Qmax). Expression of FQ by negative exponential functions FQ = k × e(Qbin×-m) smooths the product function FQ × QB that displays its maximum as a gentle hump rather than a sharp peak, but without drastically altering Qeff. However, a smooth function FQ × QB allows Qeff to react to small changes in rating curve exponents d. As d increases from <1 to >10, Qeff

  16. Potential adverse health effects of persistent organic pollutants on sea turtles: evidences from a cross-sectional study on Cape Verde loggerhead sea turtles.

    PubMed

    Camacho, María; Luzardo, Octavio P; Boada, Luis D; López Jurado, Luis F; Medina, María; Zumbado, Manuel; Orós, Jorge

    2013-08-01

    The Cape Verde nesting population of loggerhead sea turtles (Caretta caretta) is the third largest population of this species in the world. For conservation purposes, it is essential to determine how these reptiles respond to different types of anthropogenic contaminants. We evaluated the presence of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) in the plasma of adult nesting loggerheads from Boa Vista Island, Cape Verde, and studied the effects of the contaminants on the health status of the turtles using hematological and biochemical parameters. All turtles had detectable levels of non-dioxin like PCBs, whereas dioxin-like congeners (DL-PCBs) were detected in only 30% of the turtles. Packed cell volume decreased with higher concentrations of PCBs, which suggests that PCB exposure could result in anemia in sea turtles. In addition, a negative association between some OCPs and white blood cells (WBC) and thrombocyte estimate was noted. The DDT-metabolite, p,p'-DDE was negatively correlated with the Na/K ratio and, additionally, a number of correlations between certain PAHs and electrolyte balances were found, which suggest that exposure to these environmental contaminants could affect the kidneys and salt glands in sea turtles. Additionally, several correlations were observed between these environmental pollutants (OCPs and PAHs) and enzyme activity (GGT, ALT, ALP and amylase) and serum protein levels, pointing to the possibility that these contaminants could induce adverse metabolic effects in sea turtles. Our results indicate that anthropogenic pollutants are present in the Cape Verde loggerhead turtle nesting population and could exert negative effects on several health parameters. Because of the importance of this loggerhead nesting population, protective regulations at national and international levels as well as international action are necessary for assuring the conservation of this population.

  17. The effects of metal ion PCR inhibitors on results obtained with the Quantifiler(®) Human DNA Quantification Kit.

    PubMed

    Combs, Laura Gaydosh; Warren, Joseph E; Huynh, Vivian; Castaneda, Joanna; Golden, Teresa D; Roby, Rhonda K

    2015-11-01

    Forensic DNA samples may include the presence of PCR inhibitors, even after extraction and purification. Studies have demonstrated that metal ions, co-purified at specific concentrations, inhibit DNA amplifications. Metal ions are endogenous to sample types, such as bone, and can be introduced from environmental sources. In order to examine the effect of metal ions as PCR inhibitors during quantitative real-time PCR, 2800 M DNA was treated with 0.0025-18.750 mM concentrations of aluminum, calcium, copper, iron, nickel, and lead. DNA samples, both untreated and metal-treated, were quantified using the Quantifiler(®) Human DNA Quantification Kit. Quantification cycle (Cq) values for the Quantifiler(®) Human DNA and internal PCR control (IPC) assays were measured and the estimated concentrations of human DNA were obtained. Comparisons were conducted between metal-treated and control DNA samples to determine the accuracy of the quantification estimates and to test the efficacy of the IPC inhibition detection. This kit is most resistant to the presence of calcium as compared to all metals tested; the maximum concentration tested does not affect the amplification of the IPC or quantification of the sample. This kit is most sensitive to the presence of aluminum; concentrations greater than 0.0750 mM negatively affected the quantification, although the IPC assay accurately assessed the presence of PCR inhibition. The Quantifiler(®) Human DNA Quantification Kit accurately quantifies human DNA in the presence of 0.5000 mM copper, iron, nickel, and lead; however, the IPC does not indicate the presence of PCR inhibition at this concentration of these metals. Unexpectedly, estimates of DNA quantity in samples treated with 18.750 mM copper yielded values in excess of the actual concentration of DNA in the samples; fluorescence spectroscopy experiments indicated this increase was not a direct interaction between the copper metal and 6-FAM dye used to label the probe that

  18. The clear-sky greenhouse effect sensitivity to a sea surface temperature change

    NASA Technical Reports Server (NTRS)

    Duvel, J. PH.; Breon, F. M.

    1991-01-01

    The clear-sky greenhouse effect response to a sea surface temperature (SST or Ts) change is studied using outgoing clear-sky longwave radiation measurements from the Earth Radiation Budget Experiment. Considering geographical distributions for July 1987, the relation between the SST, the greenhouse effect (defined as the outgoing infrared flux trapped by atmospheric gases), and the precipitable water vapor content (W), estimated by the Special Sensor Microwave Imager, is analyzed first. A fairly linear relation between W and the normalized greenhouse effect g, is found. On the contrary, the SST dependence of both W and g exhibits nonlinearities with, especially, a large increase for SST above 25 C. This enhanced sensitivity of g and W can be interpreted in part by a corresponding large increase of atmospheric water vapor content related to the transition from subtropical dry regions to equatorial moist regions. Using two years of data (1985 and 1986), the normalized greenhouse effect sensitivity to the sea surface temperature is computed from the interannual variation of monthly mean values.

  19. Incubation Temperature Effects on Hatchling Performance in the Loggerhead Sea Turtle (Caretta caretta)

    PubMed Central

    Fisher, Leah R.; Godfrey, Matthew H.; Owens, David W.

    2014-01-01

    Incubation temperature has significant developmental effects on oviparous animals, including affecting sexual differentiation for several species. Incubation temperature also affects traits that can influence survival, a theory that is verified in this study for the Northwest Atlantic loggerhead sea turtle (Caretta caretta). We conducted controlled laboratory incubations and experiments to test for an effect of incubation temperature on performance of loggerhead hatchlings. Sixty-eight hatchlings were tested in 2011, and 31 in 2012, produced from eggs incubated at 11 different constant temperatures ranging from 27°C to 33°C. Following their emergence from the eggs, we tested righting response, crawling speed, and conducted a 24-hour long swim test. The results support previous studies on sea turtle hatchlings, with an effect of incubation temperature seen on survivorship, righting response time, crawling speed, change in crawl speed, and overall swim activity, and with hatchlings incubated at 27°C showing decreased locomotor abilities. No hatchlings survived to be tested in both years when incubated at 32°C and above. Differences in survivorship of hatchlings incubated at high temperatures are important in light of projected higher sand temperatures due to climate change, and could indicate increased mortality from incubation temperature effects. PMID:25517114

  20. Limited effectiveness of solar radiation management geoengineering in preventing sea-level rise from the Greenland Ice Sheet

    NASA Astrophysics Data System (ADS)

    Applegate, Patrick; Keller, Klaus

    2015-04-01

    The Greenland Ice Sheet (GIS) is an important contributor to present-day sea level rise, and the ice sheet's importance for sea level rise will likely increase with Arctic temperatures. Some scientists have recently suggested that geoengineering, the deliberate management of Earth's climate, could prevent sea level rise from the ice sheets. Previous efforts to assess geoengineering's effects on the GIS and sea level rise have broken important new ground, but neglect key feedbacks and/or are silent on the short-term effects of geoengineering that are perhaps most important for decision-making. Here, we use a simplified, three-dimensional model of the GIS (SICOPOLIS by Ralf Greve) to examine the response of the Greenland Ice Sheet under plausible geoengineering scenarios. We find that i) the GIS generally continues to melt over the first 100 yr after geoengineering initiation; ii) reductions in GIS sea level contributions over these first 100 yr are small; and iii) there is a delay of decades to centuries between the initiation of aggressive geoengineering and any regrowth of the ice sheet, and the rate of this regrowth is slow. However, geoengineering produces appreciable reductions in the rate of sea level rise contributions from the GIS within the first few decades. Our results suggest that past studies have overestimated the effectiveness of geoengineering in preventing mass loss from the Greenland Ice Sheet and in reversing sea level rise once it has occurred. We comment on the importance of feedbacks in the ice sheet system in assessing geoengineering's effectiveness in reducing sea level rise from the GIS.

  1. Fluid and electromagnetic transport in sea ice

    NASA Astrophysics Data System (ADS)

    Gully, Adam Spence

    vertical conductivity of first year sea ice. Together, these results lay the foundation for electromagnetic monitoring of transport phenomena in sea ice and help provide a rigorous basis for electromagnetic methods to obtain sea ice thickness data. We also modify traditional percolation models for columnar sea ice, hypothesizing that granular sea ice has a percolation threshold near a 10% brine volume fraction. This modified percolation model is then in excellent agreement with our fluid permeability field data taken in Antarctica, where granular ice is a significant component of the ice cover. Here we also develop theoretical bounds on two extensive sets of effective complex permittivity sea ice data taken in the Arctic and Antarctic. The first set of bounds assumes only knowledge of the brine volume fraction or porosity, and the second set further assumes statistical isotropy of the microstructure. We obtain excellent agreement between theory and experiment, and are able to observe the apparent violation of the isotropic bounds as the vertically oriented microstructure becomes increasingly connected for higher porosities. Moreover, these bounds are inverted to obtain estimates of the porosity from the measurements of the effective complex permittivity. We find that the temporal variations of the reconstructed porosity, which is directly related to temperature, closely follow the actual behavior. Additionally, an analytic method for obtaining bounds on the effective complex permittivity of polycrystalline composite materials is developed and applied to the effective complex permittivity of sea ice. Here we use mean single crystal orientation data and single crystal complex permittivity tensor data to obtain polycrystalline forward bounds for sea ice. The single crystal complex permittivity tensor is obtained by evaluating X-ray CT data of sea ice with known ice and brine permittivites and brine volume fraction using Comsol 3.5a. Further, inverse bounds are developed and

  2. Effect of eustatic sea-level changes on saltwater-freshwater relations in the Northern Atlantic Coastal Plain

    USGS Publications Warehouse

    Meisler, Harold; Leahy, P. Patrick; Knobel, LeRoy L.

    1984-01-01

    A finite-difference computer model was used to analyze the effect of eustatic sea-level changes on the development of the transition zone between fresh ground water and underlying saltwater in the northern Atlantic Coastal Plain. The model simulates, in cross section, the sedimentary wedge from the Delaware River estuary in New Jersey to the Continental Slope. Simulated steady-state freshwater flow is separated from static saltwater by a sharp interface. The model was used to test the sensitivity of the simulated interface position to anisotropy as well as to sea-level elevation. Increasing anisotropy causes the interface to be shallower and extend farther offshore. Lowering sea level causes the interface to be deeper and to extend farther offshore. Simulations using hydraulic conductivities based on available data suggest that the transition zone is not in equilibrium with present sea level. The position of the transition zone probably reflects a long-term average sea level of between 50 and 100 ft below present sea level. The cyclic movement of salty ground water in response to sea-level fluctuations during the Quaternary and Late Tertiary caused the saltwater to mix with freshwater, thus producing a broad transition zone. The freshwater is predominantly sodium bicarbonate in character. The saltwater, from New Jersey to Virginia, probably is a sodium calcium chloride brine. In North Carolina, it is primarily seawater.

  3. Simulated effect of deep-sea sedimentation and terrestrial weathering on projections of ocean acidification

    NASA Astrophysics Data System (ADS)

    Cao, Long; Zheng, Meidi; Caldeira, Ken

    2016-04-01

    Projections of ocean acidification have often been based on ocean carbon cycle models that do not represent deep-sea sedimentation and terrestrial weathering. Here we use an Earth system model of intermediate complexity to quantify the effect of sedimentation and weathering on projections of ocean acidification under an intensive CO2 emission scenario that releases 5000 Pg C after year 2000. In our simulations, atmospheric CO2 reaches a peak concentration of 2123 ppm near year 2300 with a maximum reduction in surface pH of 0.8. Consideration of deep-sea sedimentation and terrestrial weathering has negligible effect on these peak changes. Only after several millenniums, sedimentation and weathering feedbacks substantially affect projected ocean acidification. Ten thousand years from today, in the constant-alkalinity simulation, surface pH is reduced by ˜0.7 with 95% of the polar oceans undersaturated with respect to calcite, and no ocean has a calcite saturation horizon (CSH) that is deeper than 1000 m. With the consideration of sediment feedback alone, surface pH is reduced by ˜0.5 with 35% of the polar oceans experiencing calcite undersaturation, and 8% global ocean has a CSH deeper than 1000 m. With the addition of weathering feedback, depending on the weathering parameterizations, surface pH is reduced by 0.2-0.4 with no polar oceans experiencing calcite undersaturation, and 30-80% ocean has a CSH that is deeper than 1000 m. Our results indicate that deep-sea sedimentation and terrestrial weathering play an important role in long-term ocean acidification, but have little effect on mitigating ocean acidification in the coming centuries.

  4. Effects of food origin and availability on sea urchin condition and feeding behaviour

    NASA Astrophysics Data System (ADS)

    Livore, Juan P.; Connell, Sean D.

    2012-02-01

    The origin of food is recognised to be an important trait for sedentary consumers that have little control over the source of their food. Elevated herbivory in sea urchins is often linked to poor gonad condition as provoked by reduced food availability, but there is little recognition of the possibility that the origin of food may contribute to their poor condition and elevated feeding. This study assesses the possibility that variation in food availability and origin may together affect urchin condition and feeding rates such that they account for more intensive grazing (by Heliocidaris erythrogramma) on sheltered than exposed coasts (South Australia). We experimentally tested the hypothesis that reduced food availability from sheltered coasts would result in poor gonad condition and greater feeding rate; whilst enhanced food availability from exposed coasts would result in better condition and reduced feeding rates. We found that reduced food had negative effects on condition and positive effects on feeding rates independently of coastal source. Greater food availability did not equate to better condition, rather it was the delivery of more food from exposed than sheltered coasts that translated into the better gonad condition and lower feeding rates. These results suggest that plant origin and availability could help explain the greater impacts of these urchins on sheltered coasts. Whilst other factors such as water energy and sea urchin density may contribute to variation in herbivory our results suggest that origin of food may also play a role in sea urchin condition and behaviour. Understanding how such traits link to large scale features of the environment may improve models that account for variation in strength of consumer effects across landscapes.

  5. The subtle effects of sea water acidification on the amphipod Gammarus locusta

    NASA Astrophysics Data System (ADS)

    Hauton, C.; Tyrrell, T.; Williams, J.

    2009-08-01

    We report an investigation of the effects of increases in pCO2 on the survival, growth and molecular physiology of the neritic amphipod Gammarus locusta which has a cosmopolitan distribution in estuaries. Amphipods were reared from juvenile to mature adult in laboratory microcosms at three different levels of pH in nominal range 8.1-7.6. Growth rate was estimated from weekly measures of body length. At sexual maturity the amphipods were sacrificed and assayed for changes in the expression of genes coding for a heat shock protein (hsp70 gene) and the metabolic enzyme glyceraldehyde-3-phosphate dehydrogenase (gapdh gene). The data show that the growth and survival of this species is not significantly impacted by a decrease in sea water pH of up to 0.5 units. Quantitative real-time PCR analysis indicated that there was no significant effect of growth in acidified sea water on the sustained expression of the hsp70 gene. There was a consistent and significant increase in the expression of the gapdh gene at a pH of ~7.5 which, when combined with observations from other workers, suggests that metabolic changes may occur in response to acidification. It is concluded that sensitive assays of tissue physiology and molecular biology should be routinely employed in future studies of the impacts of sea water acidification as subtle effects on the physiology and metabolism of coastal marine species may be overlooked in conventional gross "end-point" studies of organism growth or mortality.

  6. Short Lived Climate Pollutants cause a Long Lived Effect on Sea-level Rise: Analyzing climate metrics for sea-level rise

    NASA Astrophysics Data System (ADS)

    Sterner, E.; Johansson, D. J.

    2013-12-01

    Climate change depends on the increase of several different atmospheric pollutants. While long term global warming will be determined mainly by carbon dioxide, warming in the next few decades will depend to a large extent on short lived climate pollutants (SLCP). Reducing emissions of SLCPs could contribute to lower the global mean surface temperature by 0.5 °C already by 2050 (Shindell et al. 2012). Furthermore, the warming effect of one of the most potent SLCPs, black carbon (BC), may have been underestimated in the past. Bond et al. (2013) presents a new best estimate of the total BC radiative forcing (RF) of 1.1 W/m2 (90 % uncertainty bounds of 0.17 to 2.1 W/m2) since the beginning of the industrial era. BC is however never emitted alone and cooling aerosols from the same sources offset a majority of this RF. In the wake of calls for mitigation of SLCPs it is important to study other aspects of the climate effect of SLCPs. One key impact of climate change is sea-level rise (SLR). In a recent study, the effect of SLCP mitigation scenarios on SLR is examined. Hu et al (2013) find a substantial effect on SLR from mitigating SLCPs sharply, reducing SLR by 22-42% by 2100. We choose a different approach focusing on emission pulses and analyse a metric based on sea level rise so as to further enlighten the SLR consequences of SLCPs. We want in particular to understand the time dynamics of SLR impacts caused by SLCPs compared to other greenhouse gases. The most commonly used physical based metrics are GWP and GTP. We propose and evaluate an additional metric: The global sea-level rise potential (GSP). The GSP is defined as the sea level rise after a time horizon caused by an emissions pulse of a forcer to the sea level rise after a time horizon caused by an emissions pulse of a CO2. GSP is evaluated and compared to GWP and GTP using a set of climate forcers chosen to cover the whole scale of atmospheric perturbation life times (BC, CH4, N2O, CO2 and SF6). The study

  7. Effect of food plants on the volume of repellent secretion obtained in adult Zonocerus variegatus (Orthoptera: Pyrgomorphidae).

    PubMed

    Idowu, A B; Idowu, O A

    2001-06-01

    The volume of secretion obtained from adult Zonocerus variegatus (Orthoptera: Pyrgomorphidae) was influenced by the type of food plants. Insects fed on leaves of cassava Manihot esculenta, bitter leaves Vernonia amygdalina, and a mixture of M. esculenta and Acalypha wilkesiana gave a good volume of secretion while Chromolaena odorata, Elaeis guinensis, Aspilia africana and Citrus sinensis did not favour secretion production. No significant difference was recorded in the volume of secretion obtained from Z. variegatus from the two seasons irrespective of the food plant. Similarly, food plants gave no significant difference on the volume of secretion between the two seasons.

  8. Effect of Late Holocene sea level change and deltaic lobe-shifting, Apalachicola Delta, northwest Florida

    SciTech Connect

    Donoghue, J.F. . Geology Dept.); White, N.M. . Dept. of Anthropology)

    1993-03-01

    Late Holocene environmental changes in the lower Apalachicola River region of the northwest Florida appear to be related to deltaic lobe-shifting and sea level change. Sedimentologic, archaeologic and seismic evidence all indicate a major shift in deltaic deposition approximately 2,000 years ago. The effect is observed in the mid-region of the modern Apalachicola Delta as a pronounced change from estuarine to freshwater conditions. On the barrier island chain flanking the delta the result was a change in depositional patterns with a shift in the sediment supply.

  9. The Effects of Carbon Dioxide Sequestration on Deep-sea Foraminifera in two California Margin Experiments

    SciTech Connect

    Ricketts, Erin R

    2006-01-01

    ABSTRACT Deep-sea sequestration of CO2 is being considered as a possible mitigation tool to decrease atmospheric CO2 concentrations and its associated negative effects. This study is the first to investigate potential effects of liquid carbon dioxide (CO2) injection on deep-sea foraminiferal assemblages. Foraminifera are ideal for this ecological impact investigation because of differing test composition (calcareous and non-calcareous) and thickness, and diverse epifaunal and infaunal depth preferences. The experiment was conducted August-September 2003, at 3600m off the coast of Monterey Bay, California, aboard the R/V Western Flyer using the ROV Tiburon. The pH of the site was monitored throughout the experiment by Seabird CTDs. Sediment push-cores were collected (both from the experimental and control sites) and stained to distinguish live (stained) from dead (unstained) individuals. Effects of CO2 injection on assemblages have been tracked both vertically (to 10cm depth below sea floor) and horizontally (up to 10m from CO2 injection sites), as well as between live and dead individuals. Within the corrals and underlying sediments severe pH changes (to near 4.0) were seen while over the experimental area small average reductions in ocean pH (-0.05 units) and large episodic excursions (-1.7 units) were measured resulting from CO2 injection. Exposure to this gradient of low pH caused increased mortality and dissolution of calcareous forms within corrals, as far as 5m from the injection site, and to at least 10cm depth in the sediments. This experiment revealed several major effects of CO2 injection on foraminiferal assemblages in surficial sediments: 1) total number of foraminifera in a sample decreases; 2) foraminiferal species richness decreases in both stained and unstained specimens; and 3) percentage of stained (live) forms increases. Down-core trends (to 10cm below sea floor) have revealed: 1) percent agglutinated forms decline and calcareous forms increase

  10. Early life developmental effects of marine persistent organic pollutants on the sea urchin Psammechinus miliaris.

    PubMed

    Anselmo, Henrique M R; Koerting, Lina; Devito, Sarah; van den Berg, Johannes H J; Dubbeldam, Marco; Kwadijk, Christiaan; Murk, Albertinka J

    2011-11-01

    A new 16-day echinoid early life stage (ELS) bioassay was developed to allow for prolonged observation of possible adverse effects during embryogenesis and larval development of the sea urchin Psammechinus miliaris. Subsequently, the newly developed bioassay was applied to study the effects of key marine persistent organic pollutants (POPs). Mortality, morphological abnormalities and larval development stages were quantified at specific time points during the 16-day experimental period. In contrast to amphibians and fish, P. miliaris early life development was not sensitive to dioxin-like toxicity in the prolonged early life stage test. Triclosan (TCS) levels higher than 500 nM were acutely toxic during embryo development. Morphological abnormalities were induced at concentrations higher than 50 nM hexabromocyclododecane (HBCD) and 1000 nM tetrabromobisphenol A (TBBPA). Larval development was delayed above 25 nM HBCD and 500 nM TBBPA. Heptadecafluorooctane sulfonic acid (PFOS) exposure slightly accelerated larval development at 9 days post-fertilization (dpf). However, the accelerated development was no longer observed at the end of the test period (16 dpf). The newly developed 16-day echinoid ELS bioassay proved to be sensitive to toxic effects of POPs that can be monitored for individual echinoid larvae. The most sensitive and dose related endpoint was the number of developmental penalty points. By manipulation of the housing conditions, the reproductive season could be extended from 3 to 9 months per year and the ELS experiments could be performed in artificial sea water as well.

  11. Monitoring Arctic Sea ice using ERTS imagery. [Bering Sea, Beaufort Sea, Canadian Archipelago, and Greenland Sea

    NASA Technical Reports Server (NTRS)

    Barnes, J. C.; Bowley, C. J.

    1974-01-01

    Because of the effect of sea ice on the heat balance of the Arctic and because of the expanding economic interest in arctic oil and other minerals, extensive monitoring and further study of sea ice is required. The application of ERTS data for mapping ice is evaluated for several arctic areas, including the Bering Sea, the eastern Beaufort Sea, parts of the Canadian Archipelago, and the Greenland Sea. Interpretive techniques are discussed, and the scales and types of ice features that can be detected are described. For the Bering Sea, a sample of ERTS imagery is compared with visual ice reports and aerial photography from the NASA CV-990 aircraft.

  12. The Seagrass Effect Turned Upside Down Changes the Prospective of Sea Urchin Survival and Landscape Implications

    PubMed Central

    Farina, Simone; Guala, Ivan; Oliva, Silvia; Piazzi, Luigi; Pires da Silva, Rodrigo; Ceccherelli, Giulia

    2016-01-01

    Habitat structure plays an important mediating role in predator-prey interactions. However the effects are strongly dependent on regional predator pools, which can drive predation risk in habitats with very similar structure in opposite directions. In the Mediterranean Sea predation on juvenile sea urchins is commonly known to be regulated by seagrass structure. In this study we test whether the possibility for juvenile Paracentrotus lividus to be predated changes in relation to the fragmentation of the seagrass Posidonia oceanica (four habitat classes: continuous, low-fragmentation, high-fragmentation and rocks), and to the spatial arrangement of such habitat classes at a landscape scale. Sea urchin predation risk was measured in a 20-day field experiment on tethered individuals placed in three square areas 35×35 m2 in size. Variability of both landscape and habitat structural attributes was assessed at the sampling grain 5×5 m2. Predation risk changed among landscapes, as it was lower where more ‘rocks’, and thus less seagrass, were present. The higher risk was found in the ‘continuous’ P. oceanica rather than in the low-fragmentation, high-fragmentation and rock habitats (p-values = 0.0149, 0.00008, and 0.0001, respectively). Therefore, the expectation that juvenile P. lividus survival would have been higher in the ‘continuous’ seagrass habitat, which would have served as shelter from high fish predation pressure, was not met. Predation risk changed across habitats due to different success between attack types: benthic attacks (mostly from whelks) were overall much more effective than those due to fish activity, the former type being associated with the ‘continuous’ seagrass habitat. Fish predation on juvenile sea urchins on rocks and ‘high-fragmentation’ habitat was less likely than benthic predation in the ‘continuous’ seagrass, with the low seagrass patch complexity increasing benthic activity. Future research should be aimed at

  13. Protective effects of chicken egg yolk antibody (IgY) against experimental Vibrio splendidus infection in the sea cucumber (Apostichopus japonicus).

    PubMed

    Li, Xiaoyu; Jing, Kailin; Wang, Xitao; Li, Yuan; Zhang, Meixia; Li, Zhen; Xu, Le; Wang, Lili; Xu, Yongping

    2016-01-01

    Vibrio splendidus is one of the most harmful pathogens associated with skin ulceration syndrome in the sea cucumber (Apostichopus japonicus) due to its high virulence and frequency of appearance. The objective of this study was to determine the effectiveness of chicken egg yolk antibody (IgY) against V. splendidus infection in the sea cucumber. Whole V. splendidus cells were used as an immunogen to immunize 20 White Leghorn hens (25 weeks old). IgY was produced from egg yolks obtained from these immunized hens using water dilution, two-step salt precipitation and ultrafiltration. The purity of the IgY produced was approximately 83%. Enzyme-linked Immunosorbent Assay indicated a high specificity for IgY with a maximum antibody titer of 320,000. The growth of V. splendidus in liquid medium was significantly inhibited by IgY in a dose-dependent manner at concentrations ranging from 1 to 10 mg/mL. The protective effects of IgY were evaluated in sea cucumber by intraperitoneally injecting anti-V. splendidus IgY antibodies (10 mg/mL) or immersing the sea cucumber in aqueous IgY (1 g/L) after an intraperitoneal injection of V. splendidus. Intraperitoneal injection resulted in an 80% survival while immersion resulted in a 75% survival during the 11-day experimental period. The survival rates were significantly higher than the positive control and the non-specific IgY group (P < 0.05). As well, the bacterial burden in the respiratory tree, intestine and coelomic liquid was significantly (P < 0.05) lower in sea cucumber treated with specific IgY than those treated with non-specific IgY. The phagocytosis of coelomocytes for V. splendidus in the presence of specific IgY was significantly (P < 0.05) higher than that obtained with non-specific IgY or without IgY, suggesting that specific IgY enhanced phagocytic activity. The current work suggests that specific IgY has potential for protecting sea cucumbers against V. splendidus infection. PMID:26592708

  14. Protective effects of chicken egg yolk antibody (IgY) against experimental Vibrio splendidus infection in the sea cucumber (Apostichopus japonicus).

    PubMed

    Li, Xiaoyu; Jing, Kailin; Wang, Xitao; Li, Yuan; Zhang, Meixia; Li, Zhen; Xu, Le; Wang, Lili; Xu, Yongping

    2016-01-01

    Vibrio splendidus is one of the most harmful pathogens associated with skin ulceration syndrome in the sea cucumber (Apostichopus japonicus) due to its high virulence and frequency of appearance. The objective of this study was to determine the effectiveness of chicken egg yolk antibody (IgY) against V. splendidus infection in the sea cucumber. Whole V. splendidus cells were used as an immunogen to immunize 20 White Leghorn hens (25 weeks old). IgY was produced from egg yolks obtained from these immunized hens using water dilution, two-step salt precipitation and ultrafiltration. The purity of the IgY produced was approximately 83%. Enzyme-linked Immunosorbent Assay indicated a high specificity for IgY with a maximum antibody titer of 320,000. The growth of V. splendidus in liquid medium was significantly inhibited by IgY in a dose-dependent manner at concentrations ranging from 1 to 10 mg/mL. The protective effects of IgY were evaluated in sea cucumber by intraperitoneally injecting anti-V. splendidus IgY antibodies (10 mg/mL) or immersing the sea cucumber in aqueous IgY (1 g/L) after an intraperitoneal injection of V. splendidus. Intraperitoneal injection resulted in an 80% survival while immersion resulted in a 75% survival during the 11-day experimental period. The survival rates were significantly higher than the positive control and the non-specific IgY group (P < 0.05). As well, the bacterial burden in the respiratory tree, intestine and coelomic liquid was significantly (P < 0.05) lower in sea cucumber treated with specific IgY than those treated with non-specific IgY. The phagocytosis of coelomocytes for V. splendidus in the presence of specific IgY was significantly (P < 0.05) higher than that obtained with non-specific IgY or without IgY, suggesting that specific IgY enhanced phagocytic activity. The current work suggests that specific IgY has potential for protecting sea cucumbers against V. splendidus infection.

  15. The effects of sea-level rise on water quality in coastal floodplain sediments

    NASA Astrophysics Data System (ADS)

    Wong, Vanessa; Johnston, Scott; Burton, Edward; Bush, Richard; Sullivan, Leigh; Slavich, Peter

    2013-04-01

    Sea level has risen approximately 1.2 mm/year over the last 100 years (Hennessy et al. 2004) and is predicted to rise up to 80 cm by 2100 relative to 1990 sea levels (IPCC 2007). The number of extreme events related to sea level such as higher sea levels and increased inter-annual variability have also increased in frequency in the same time period (Hennessy et al. 2004). Globally, large areas of coastal and estuarine floodplains are underlain by sulfidic sediments and acid sulfate soils (ASS). These sediments frequently contain high concentrations of acidity and trace metals. A significant portion of the stored acidity occurs in the form of exchangeable and hydrolysable acidic metal cations such as Al and Fe. Watertables in these environments are often close to the surface and intercepted by relatively shallow drains. Due to their low elevation and locations, these floodplains are highly susceptible to pulses of saline water caused by saltwater intrusion, storm surge and rising sea levels. Construction of extensive drainage systems has further increased the susceptibility of the floodplain to seawater inundation by increasing connectivity to the estuarine channel. This risk is likely to increase in the future with predicted increases in sea level and extreme events due to climate change. This study uses both batch experiments to determine the effects of increasing ionic strength on exchange processes and trace metal desorption in oxidised floodplain sediments and sulfidic drain sediments, and intact soil cores to determine the surface water-porewater interactions over the short term following seawater inundation in coastal floodplain sediments. We found that that saline inundation of oxidised ASS floodplain sediments, even by relatively brackish water may cause rapid, shorter-term water quality changes and a pulse release of acidity due to desorption of acidic metal cations (Wong et al. 2010). We also found that trace metals can be mobilised from sulfidic

  16. Effect of the temperature variation between Mediterranean Sea and Syrian deserts on the dust storm occurrence in the western half of Iran

    NASA Astrophysics Data System (ADS)

    Amanollahi, Jamil; Kaboodvandpour, Shahram; Qhavami, Samira; Mohammadi, Bakhtiyar

    2015-03-01

    Recent dust storms have caused crises in western Iran, which necessitate the prediction of these storms a few days before their occurrence. This is the first study of its type that analyzes the effect of temperature differences between the Mediterranean Sea surface and Syrian deserts (creation zone of the dusts storms) on the formation of dust storms in the west of Iran. The study also seeks to identify any changes in the atmospheric temperature created by the extreme dust storm of July 5, 2009 in west of Iran (Sanandaj City). In this study, the MODIS images from 2000 to 2008, and particulate matter data of the Sanandaj station from 2008 to 2012 were utilized to identify the dust storm days. The Mediterranean Sea surface temperature data were extracted from NOAA satellites for dust storm days up to four days preceding them. The web site of world weather was used to obtain the temperature of Damascus, Syria station as the selected land station. According to the results, significant differences were acquired between surface temperatures of Damascus station and the Mediterranean Sea in the dust storm days and up to three days before them. As the dust storm days approached, a rising trend was observed in changes of the temperature difference between land and sea. Thermal map analysis of the atmosphere of the Syrian deserts on July 5, 2009 showed significant decrease in the levels of 1000 hPa and 500 hPa but for the days preceding it no significant changes were observed. It can be concluded that the temperature difference between the Mediterranean Sea surface and the Syrian deserts four days before the dust storm occurrences is the important factor in predicting this event.

  17. Effect of constant vorticity on the statistical properties of extreme sea waves.

    NASA Astrophysics Data System (ADS)

    Fernández, Leandro; Francius, Marc; Touboul, Julien; Kharif, Christian

    2016-04-01

    Here a comparative analysis of the statistical properties of surface gravity waves in water of deep and finite depths is discussed by analysing numerical simulations with and without vorticity. It is restricted to one-dimensional direction of propagation of water waves with constant vorticity and without dissipation. Numerical simulations of nonlinear surface waves on a linear shear current are performed using an extension of the well-known high-order spectral method (HOSM) (Francius et al. 2013). An adjustment procedure for initializing the nonlinear free surface simulations with linear solutions is validated and used to study the nonlinear evolution of a sea wave obtained from dressing a JONSWAP spectrum (Soriano et al, 2006).

  18. Simulation Study of Effects of Solar Irradiance and Sea Surface Temperature on Monsoons and Global Circulation

    NASA Technical Reports Server (NTRS)

    Sud, Y. C.; Walker, G. K.; Mehta, V.; Lau, W. K.-M.; Einaudi, Franco (Technical Monitor)

    2001-01-01

    A recent version of the GEOS 2 GCM was used to isolate the roles of the annual cycles of solar irradiation and/or sea-surface temperatures (SSTs) on the simulated circulation and rainfall. Four 4-year long integrations were generated with the GCM. The first integration, called Control Case, used daily-interpolated SSTs from a 30 year monthly SST climatology that was obtained from the analyzed SST-data, while the solar irradiation at the top of the atmosphere was calculated normally at hourly intervals. The next two cases prescribed the SSTs or the incoming solar irradiance at the top of the atmosphere at their annual mean values, respectively while everything else was kept the same as in the Control Case. In this way the influence of the annual cycles of both external forcings was isolated.

  19. Effect of Air-Sea coupling on the Frequency Distribution of Intense Tropical Cyclones over the Northwestern Pacific

    NASA Astrophysics Data System (ADS)

    Ogata, Tomomichi; Mizuta, Ryo; Adachi, Yukimasa; Murakami, Hiroyuki; Ose, Tomomaki

    2016-04-01

    Effect of air-sea coupling on the frequency distribution of intense tropical cyclones (TCs) over the northwestern Pacific (NWP) region is investigated using an atmosphere and ocean coupled general circulation model (AOGCM). Monthly varying flux adjustment enables AOGCM to simulate both subseasonal air-sea interaction and realistic seasonal to interannual SST variability. The maximum of intense TC distribution around 20-30°N in the AGCM shifts equatorward in the AOGCM due to the air-sea coupling. Hence AOGCM reduces northward intense TC distribution bias seen in AGCM. Over the NWP, AOGCM-simulated SST variability is large around 20-30°N where the warm mixed layer becomes shallower rapidly. Active entrainment from subsurface water over this region causes stronger SST cooling and hence TC intensity decreases. These results suggest that air-sea coupling characterized by subsurface oceanic condition causes more realistic distribution of intense TCs over the NWP.

  20. Limited effects of a keystone species: Trends of sea otters and kelp forests at the Semichi Islands, Alaska

    USGS Publications Warehouse

    Konar, B.

    2000-01-01

    Sea otters are well known as a keystone species because of their ability to transform sea urchin-dominated communities into kelp-dominated communities by preying on sea urchins and thus reducing the intensity of herbivory. After being locally extinct for more than a century, sea otters re-colonized the Semichi Islands in the Aleutian Archipelago, Alaska in the early 1990s. Here, otter populations increased to about 400 individuals by 1994, but rapidly declined to about 100 by 1997. Roughly 7 yr after initial otter re-colonization, there were only marginal changes in sea urchin biomass, mean maximum test size, and kelp density. These small changes may be the first steps in the cascading effects on community structure typically found with the invasion of a keystone species. However, no wholesale change in community structure occurred following re-colonization and growth of the sea otter population. Instead, this study describes a transition state and identifies factors such as keystone species density and residence time that can be important in dictating the degree to which otter effects are manifested.

  1. Effect of inositol and tri-iodothyronine on the hormonal responsiveness of hepatocytes obtained from partially hepatectomized rats.

    PubMed Central

    Huerta-Bahena, J; García-Sáinz, J A

    1984-01-01

    Hepatocytes obtained from animals partially hepatectomized (72 h before the experiment) have a diminished responsiveness to alpha 1-adrenergic amines, vasopressin, angiotensin and glucagon and an increased responsiveness to beta-adrenergic amines. Administration of inositol or tri-iodothyronine to the hepatectomized animals induced a recovery in the hepatocyte responsiveness to the Ca2+-dependent hormones and abolished that to beta-adrenergic amines; the response to glucagon was not improved. PMID:6508748

  2. Links between Sea Level in the northern Adriatic sea and large scale patterns

    NASA Astrophysics Data System (ADS)

    Scarascia, L.; Lionello, P.

    2012-04-01

    The study analyzes the link between Northern Adriatic sea level (SL) and three variables: sea level pressure over European and North-Atlantic area (SLP), Mediterranean sea surface temperature (SST) and Mediterranean sea surface salinity (SSS). Sea level data are provided by monthly values recorded at 7 tide gauges stations distributed along the north-Italian and Croatian coasts (available at the PSMSL Permanent Service of Mean Sea Level). SLP data are provided by the EMULATE data set. Mediterranean SST and SSS data are extracted from the MEDATLAS/2002 database. The study shows that annual sea level variations at Northern Adriatic stations are very coherent so that the northern Adriatic sea level can be reconstructed since 1905 on the basis of only two stations: Venice and Trieste, whose data cover almost the entire 20th century (whereas Croatian data cover only the second half of the century). The inverse barometric, thermosteric and halosteric effects provide the physical basis for a local relation of SL with SLP, SST, SSS implying, if other effects are absent, a sea level increase for increasing temperature and decreasing atmospheric pressure and salinity. However, the statistical model used to quantify the link between SL and these three forcings shows that they have produced no important trend and they cannot explain the observed trend of Northern Adriatic Sea level during the second half of the 20th century. The observed trend can therefore be interpreted as the superposition of land movement and a remote cause. Using SLP, SST and SSS from climate model simulations, no trend is obtained during the 20th century, as well. The same model simulations, considering their continuations for the 21st century show that local effects (mainly warming of water masses) are likely to produce an increase of about 10cm (with a large uncertainty) at the end of the century. The global signal and the regional land movements have to be added to this result to obtain the actual

  3. IP effects on electromagnetic data of deep-sea hydrothermal deposits in time domain

    NASA Astrophysics Data System (ADS)

    KIM, H. J.; Jang, H.; Ha, W.

    2015-12-01

    A transient electromagnetic (TEM) system using a small loop source is advantageous to the development of compact, autonomous instruments which are well suited to submersible-based surveys. Since electrical conductivity of subseafloor materials can be frequency dependent, these induced polarization (IP) effects may affect the reliability of TEM data interpretation. In this study, we investigate IP effects on TEM responses of deep-sea hydrothermal mineral deposits with a thin sediment cover. Time-domain target signals are larger and appear earlier in horizontal magnetic fields than in vertical ones. IP effects cause transient magnetic fields to enhance initially, to decay rapidly and then to reverse the polarity. The DC conductivity and IP chargeability in Cole-Cole parameters influence the time of sign reversal and the enhancement of the target response, simultaneously. The reversal time is almost invariant with the time constant while the target signal is almost invariant with the frequency exponent.

  4. Effect of environmental uncertainty on low frequency sonar propagation in a shallow sea

    NASA Astrophysics Data System (ADS)

    Chen, Feng; Shapiro, Georgy; Thain, Richard

    2013-04-01

    . The effect on acoustic propagation using predicted and observed environmental data respectively are evaluated in the presence of dynamical features (e.g. fronts and stratifications). The study compares the sensitivity of the propagation loss to variations between the observed and simulated temperature and salinity fields. This study also analyses the effects of various seabed characteristics on the acoustic propagation loss in the Celtic Sea. A comprehensive statistical and probabilistic analysis based on Taylor diagrams is presented. The main conclusion is that the ability of the ocean model to resolve the temperature and salinity fronts is crucial to the accuracy of acoustic simulation.

  5. Modeled Effects of Encapsulated Crude Oil on Light Transmission Through Sea Ice

    NASA Astrophysics Data System (ADS)

    Carns, R.; Light, B.

    2015-12-01

    As part of ongoing research to further advance a range of oil spill response technologies in the Arctic, nine oil and gas companies established the Arctic Oil Spill Response Technology Joint Industry Programme (JIP) in 2012. One research theme is designed to expand the industry's remote-sensing and monitoring capabilities. A suite of sensors was tested on a saltwater ice sheet grown in the U.S. Army Corps of Engineers Cold Regions Research and Engineering Laboratory (CRREL) Ice Engineering Research Facility test basin while oil was injected under the ice at different points in the ice growth. The ice continued to grow after the oil injection, allowing the oil to become encapsulated so testing could occur with various thicknesses of ice below the oil. Measurements of apparent optical properties were taken before and after the injection of oil and during various stages of ice growth. We have used a Monte Carlo model of radiative transfer for sea ice [Light et al., 2003] to explore light transmission through sea ice containing encapsulated oil. This model uses a cylindrical domain, making it well-suited for determining how large a pool of oil encapsulated in a given thickness of ice must be before it is detectable from beneath the ice cover. We use this model in combination with the optical observations to predict the amount of light transmitted and reflected from sea ice of various thicknesses containing oil. We also examine the effects of a scattering layer on the ice surface, as would commonly be present in the Arctic, either in the form of snow or the surface scattering layer that develops on melting ice. We evaluate the feasibility of distinguishing between different types of oil based on the spectral signature of light transmitted through the ice. Further model sensitivity studies yield insight about the effects of the distribution of the oil within the ice cover. Light, B., G. A. Maykut, and T. C. Grenfell (2003), A two-dimensional Monte Carlo model of

  6. Effects of environment factors on initiation of sperm motility in sea cucumber Apostichopus japonicus (Selenka)

    NASA Astrophysics Data System (ADS)

    Yu, Li; Shao, Mingyu; Bao, Zhenmin; Hu, Jingjie; Zhang, Zhifeng

    2011-06-01

    Sperm of sea cucumber Apostichopus japonicus (Selenka) were quiescent in electrolyte NaCl solution and artificial seawater (ASW) and nonelectrolyte glucose and mannitol solutions when the osmolality was less than 200 mOsm kg-1. The sperm started to be motile as a result of increased osmolality, indicating an osmolality-dependent initiation of sperm motility in sea cucumber. After a brief incubation in hypotonic NaCl and glucose solutions with osmolalities of 200 and 400 mOsm kg-1, sperm lost partial motile ability. Sperm became immobilized when pH was 6.0 in NaCl, glucose and mannitol solutions, suggesting that an H+ release is involved in sperm activation. The decreased pH had no effect on the percentage of motile sperm in ASW, whereas it delayed the time period to reach the maximum motility (motilitymax). Extracellular Ca2+ in electrolyte solutions was not essential for motility stimulation but shortened the time of reaching motilitymax. When Ca2+ was mixed in nonelectrolyte solutions the sperm motility was completely suppressed. The K+ channel blocker, quinine, suppressed the sperm motility in electrolyte solution, showing a possible involvement of K+ transport in the process. High K+ concentration did not affect the sperm motility in NaCl solution, but decreased it in ASW and almost entirely suppressed it in nonelectrolyte solutions. The different effects of pH and K+ in ASW and NaCl solution indicate that external ions may also regulate sperm motility.

  7. Antioxidant, cytoprotective and antibacterial effects of Sea buckthorn (Hippophae rhamnoides L.) leaves.

    PubMed

    Upadhyay, Nitin K; Kumar, M S Yogendra; Gupta, Asheesh

    2010-12-01

    The present study was carried out to investigate the antioxidant, cytoprotective and antibacterial effects of aqueous and hydroalcoholic extracts of Hippophae rhamnoides L. (Sea buckthorn) (SBT) leaves by using various in vitro systems and analysis of marker compounds by reverse phase-high performance liquid chromatography (RP-HPLC). The chemical composition of the leaf extracts was quantified by colorimetric reaction in terms of total phenol and flavonoids contents. Further, some of its bioactive phenolic constituents, such as quercetin-3-O-galactoside, quercetin-3-O-glucoside, kaempferol and isorhamnetin were also quantified in both SBT leaf extracts by RP-HPLC. The SBT leaf extracts exhibited potent antioxidant activity determined by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Further, both extracts were observed to have cytoprotective activity against hydrogen peroxide and hypoxanthine-xanthine oxidase induced damage to BHK-21 cell line. The SBT leaf extracts showed growth inhibiting effect against Bacillus cereus, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis. These observations suggest that aqueous and hydroalcoholic extracts of Sea buckthorn leaves have marked antioxidant, cytoprotective and antibacterial activities. PMID:20854873

  8. Effects of bisphenol A on the embryonic development of sea urchin (Paracentrotus lividus).

    PubMed

    Ozlem, Cakal Arslan; Hatice, Parlak

    2008-06-01

    Bisphenol A (BPA), is one of the most important industrial chemicals synthesized for diverse applications. In this study, tests for embryotoxic and spermiotoxic effects of BPA were utilized in the sperms and embryos of the sea urchin Paracentrotus lividus. The sperm and eggs of sea urchins were exposed to increasing concentrations of BPA (300-3500 microg/L) under static conditions. The endpoints were successful sperm fertilization, larval malformations, developmental arrest, and embryonic/larval mortality. BPA concentration (300 microg/L) had spermiotoxic and embryotoxic effects on this species. A dose-response related reduction was observed in fertilization success and significant increases in the number of larvae with skeleton malformations at the pluteus stage when the sperms were exposed BPA. The embryotoxicity of BPA is concentration-dependent and significant growth reduction at the early life stages and an increase in larval malformations as skeleton deformities at the pluteus stage were observed. It can be concluded that BPA adversely affects the reproduction and embryonic developmental stages of the P. lividus and this is of great ecological importance due to the hazard at the population level. PMID:18214894

  9. Effects of coded-wire-tagging on stream-dwelling Sea Lamprey larvae

    USGS Publications Warehouse

    Johnson, Nicholas; Swink, William D.; Dawson, Heather A.; Jones, Michael L.

    2016-01-01

    The effects of coded wire tagging Sea Lamprey Petromyzon marinus larvae from a known-aged stream-dwelling population were assessed. Tagged larvae were significantly shorter on average than untagged larvae from 3 to 18 months after tagging. However, 30 months after tagging, the length distribution of tagged and untagged larvae did not differ and tagged Sea Lampreys were in better condition (i.e., higher condition factor) and more likely to have undergone metamorphosis than the untagged population. The reason why tagged larvae were more likely to metamorphose is not clear, but the increased likelihood of metamorphosis could have been a compensatory response to the period of slower growth after tagging. Slower growth after tagging was consistent across larval size-classes, so handling and displacement from quality habitat during the early part of the growing season was likely the cause rather than the tag burden. The tag effects observed in this study, if caused by displacement and handling, may be minimized in future studies if tagging is conducted during autumn after growth has concluded for the year.

  10. Growth-promoting effects of sustained swimming in fingerlings of gilthead sea bream (Sparus aurata L.).

    PubMed

    Blasco, Josefina; Moya, A; Millán-Cubillo, A; Vélez, E J; Capilla, E; Pérez-Sánchez, J; Gutiérrez, J; Fernández-Borrás, J

    2015-12-01

    Fish growth is strongly influenced by environmental and nutritional factors and changing culture conditions can help optimize it. The importance of early-life experience on the muscle phenotype later in life is well known. Here, we study the effects of 5 weeks of moderate and sustained swimming activity (5 BL s(-1)) in gilthead sea bream during early development. We analysed growth and body indexes, plasma IGF-I and GH levels, feed conversion, composition [proximate and isotopic ((15)N/(13)C)] and metabolic key enzymes (COX, CS, LDH, HOAD, HK, ALAT, ASAT) of white muscle. Moderate and continuous exercise in fingerlings of gilthead sea bream increased plasma IGF-I, whereas it reduced plasma GH. Under these conditions, growth rate improved without any modification to feed intake through an increase in muscle mass and a reduction in mesenteric fat deposits. There were no changes in the content and turnover of muscle proteins and lipid reserves. Glycogen stores were maintained, but glycogen turnover was higher in white muscle of exercised fish. A lower LDH/CS ratio demonstrated an improvement in the aerobic capacity of white muscle, while a reduction in the COX/CS ratio possibly indicated a functional adaptation of mitochondria to adjust to the tissue-specific energy demand and metabolic fuel availability in exercised fish. We discuss the synergistic effects of dietary nutrients and sustained exercise on the different mitochondrial responses.

  11. The positive effects of typhoons on the fish CPUE in the South China Sea

    NASA Astrophysics Data System (ADS)

    Yu, Jie; Tang, Danling; Chen, Guobao; Li, Yongzhen; Huang, Zirong; Wang, Sufen

    2014-08-01

    Due to the logistical difficulties associated with fish data sampling after typhoons, short-term effects of typhoons on fishery in the South China Sea (SCS) have not been well-understood. The present study is to evaluate the impacts on the fish catch per unit effort (CPUE) owing to the three typhoons Chanthu, Vicente, and Kai-tak in the northwestern SCS, using long-term fish catch data and satellite data. The results show that the CPUE of total catch and some sorted catches have been changing because of the typhoons. On total catch, firstly, the CPUE has increased approximately 0.32 kg h-1 kw-1, 0.20 kg h-1 kw-1, and 0.25 kg h-1 kw-1 during the three typhoon periods. Then, the CPUEs decreased to the pre-typhoon level in about three weeks. Thirdly, among the three typhoons, the slow-moving Chanthu has caused a larger increase in CPUE. The typhoons impact was two-pronged, depending on fish species. One is the positive effects on meso-demersal fishes, cephalopoda and pelagic fishes. The other is the increase in CPUE of low trophic level carnivorous fishes after the three typhoons. This research provided the first evidence of CPUE increase after typhoons in the open sea.

  12. Identification of anthropogenic effects and seasonality on water quality in Daya Bay, South China Sea.

    PubMed

    Wu, Mei-Lin; Wang, You-Shao; Sun, Cui-Ci; Wang, Haili; Dong, Jun-De; Han, Shu-Hua

    2009-07-01

    Thirteen water quality parameters from 12 monitoring stations were collected to study the effects caused by climate and anthropogenic activities on water quality in 2003 in Daya Bay, South China Sea. The data matrix has been built according to the results, which were analyzed by fuzzy c-mean cluster (FCM) and cluster analysis (CA). This analysis has identified anthropogenic effects and seasonal characters of water quality. The dry and wet seasonality have been demonstrated with FCM and CA. The precipitation and the Southeast Asian monsoons, northeasterly from October to the next April and southwesterly from May to September have also an important influence on water quality in Daya Bay. In the spatial pattern, two groups have been classified with FCM and CA. Cluster I consisted of the sites S3, S8, S10 and S11 in the west and north coastal parts of Daya Bay. Cluster I is mainly related to anthropogenic activities such as fish-farming. Cluster II consisted of the rest of the stations in the center, east and south parts of Daya Bay. Cluster II is mainly related to seawater input from South China Sea. Thus, fuzzy c-mean cluster and cluster analysis can be an important tool for the successful characterization of regional-scale water quality.

  13. Development of tools for integrated monitoring and assessment of hazardous substances and their biological effects in the Baltic Sea.

    PubMed

    Lehtonen, Kari K; Sundelin, Brita; Lang, Thomas; Strand, Jakob

    2014-02-01

    The need to develop biological effects monitoring to facilitate a reliable assessment of hazardous substances has been emphasized in the Baltic Sea Action Plan of the Helsinki Commission. An integrated chemical-biological approach is vitally important for the understanding and proper assessment of anthropogenic pressures and their effects on the Baltic Sea. Such an approach is also necessary for prudent management aiming at safeguarding the sustainable use of ecosystem goods and Services. The BEAST project (Biological Effects of Anthropogenic Chemical Stress: Tools for the Assessment of Ecosystem Health) set out to address this topic within the BONUS Programme. BEAST generated a large amount of quality-assured data on several biological effects parameters (biomarkers) in various marine species in different sub-regions of the Baltic Sea. New indicators (biological response measurement methods) and management tools (integrated indices) with regard to the integrated monitoring approach were suggested.

  14. Effect of sea-level variation on upper-slope depositional processes offshore of Tiber delta, Tyrrhenian Sea, Italy

    USGS Publications Warehouse

    Chiocci, F.L.; Normark, W.R.

    1992-01-01

    The upper slope and outer shelf in front of the Tiber River mouth (east-central Tyrrhenian Sea) exhibits a series of about 15 gullies that are not clearly related to present-day erosional or depositional processes. An extensive, high-resolution, seismic-reflection profiling survey of a 450 km2 area in front of the Tiber delta shows several generations of similar features within the older depositional sequences underlying the outer continental shelf. The gully relief appears dominantly depositional, probably developed during lowstand periods when the Tiber River mouth was relatively near the shelf break. The position of the gullied intervals, including those on the modern slope relict from the last lowstand, shows a successive northward shift with time. This northward shift indicates continued tilting of this part of the eastern Tyrrhenian continental margin, probably resulting from a continued subsidence to the north. ?? 1992.

  15. Intermittent sea-level acceleration

    NASA Astrophysics Data System (ADS)

    Olivieri, M.; Spada, G.

    2013-10-01

    Using instrumental observations from the Permanent Service for Mean Sea Level (PSMSL), we provide a new assessment of the global sea-level acceleration for the last ~ 2 centuries (1820-2010). Our results, obtained by a stack of tide gauge time series, confirm the existence of a global sea-level acceleration (GSLA) and, coherently with independent assessments so far, they point to a value close to 0.01 mm/yr2. However, differently from previous studies, we discuss how change points or abrupt inflections in individual sea-level time series have contributed to the GSLA. Our analysis, based on methods borrowed from econometrics, suggests the existence of two distinct driving mechanisms for the GSLA, both involving a minority of tide gauges globally. The first effectively implies a gradual increase in the rate of sea-level rise at individual tide gauges, while the second is manifest through a sequence of catastrophic variations of the sea-level trend. These occurred intermittently since the end of the 19th century and became more frequent during the last four decades.

  16. Effects of age, colony, and sex on mercury concentrations in California sea lions

    USGS Publications Warehouse

    McHuron, Elizibeth A; Peterson, Sarah H.; Ackerman, Josh; Melin, Sharon R.; Harris, Jeffrey D.; Costa, Daniel P.

    2016-01-01

    We measured total mercury (THg) concentrations in California sea lions (Zalophus californianus) and examined how concentrations varied with age class, colony, and sex. Because Hg exposure is primarily via diet, we used nitrogen (δ 15N) and carbon (δ 13C) stable isotopes to determine if intraspecific differences in THg concentrations could be explained by feeding ecology. Blood and hair were collected from 21 adult females and 57 juveniles from three colonies in central and southern California (San Nicolas, San Miguel, and Año Nuevo Islands). Total Hg concentrations ranged from 0.01 to 0.31 μg g−1 wet weight (ww) in blood and 0.74 to 21.00 μg g−1 dry weight (dw) in hair. Adult females had greater mean THg concentrations than juveniles in blood (0.15 vs. 0.03 μg−1 ww) and hair (10.10 vs. 3.25 μg−1 dw). Age class differences in THg concentrations did not appear to be driven by trophic level or habitat type because there were no differences in δ 15N or δ 13C values between adults and juveniles. Total Hg concentrations in adult females were 54 % (blood) and 24 % (hair) greater in females from San Miguel than females from San Nicolas Island, which may have been because sea lions from the two islands foraged in different areas. For juveniles, we detected some differences in THg concentrations with colony and sex, although these were likely due to sampling effects and not ecological differences. Overall, THg concentrations in California sea lions were within the range documented for other marine mammals and were generally below toxicity benchmarks for fish-eating wildlife.

  17. Effects of Age, Colony, and Sex on Mercury Concentrations in California Sea Lions.

    PubMed

    McHuron, Elizabeth A; Peterson, Sarah H; Ackerman, Joshua T; Melin, Sharon R; Harris, Jeffrey D; Costa, Daniel P

    2016-01-01

    We measured total mercury (THg) concentrations in California sea lions (Zalophus californianus) and examined how concentrations varied with age class, colony, and sex. Because Hg exposure is primarily via diet, we used nitrogen (δ (15)N) and carbon (δ (13)C) stable isotopes to determine if intraspecific differences in THg concentrations could be explained by feeding ecology. Blood and hair were collected from 21 adult females and 57 juveniles from three colonies in central and southern California (San Nicolas, San Miguel, and Año Nuevo Islands). Total Hg concentrations ranged from 0.01 to 0.31 μg g(-1) wet weight (ww) in blood and 0.74 to 21.00 μg g(-1) dry weight (dw) in hair. Adult females had greater mean THg concentrations than juveniles in blood (0.15 vs. 0.03 μg(-1) ww) and hair (10.10 vs. 3.25 μg(-1) dw). Age class differences in THg concentrations did not appear to be driven by trophic level or habitat type because there were no differences in δ (15)N or δ (13)C values between adults and juveniles. Total Hg concentrations in adult females were 54 % (blood) and 24 % (hair) greater in females from San Miguel than females from San Nicolas Island, which may have been because sea lions from the two islands foraged in different areas. For juveniles, we detected some differences in THg concentrations with colony and sex, although these were likely due to sampling effects and not ecological differences. Overall, THg concentrations in California sea lions were within the range documented for other marine mammals and were generally below toxicity benchmarks for fish-eating wildlife. PMID:26259982

  18. Effects of Age, Colony, and Sex on Mercury Concentrations in California Sea Lions.

    PubMed

    McHuron, Elizabeth A; Peterson, Sarah H; Ackerman, Joshua T; Melin, Sharon R; Harris, Jeffrey D; Costa, Daniel P

    2016-01-01

    We measured total mercury (THg) concentrations in California sea lions (Zalophus californianus) and examined how concentrations varied with age class, colony, and sex. Because Hg exposure is primarily via diet, we used nitrogen (δ (15)N) and carbon (δ (13)C) stable isotopes to determine if intraspecific differences in THg concentrations could be explained by feeding ecology. Blood and hair were collected from 21 adult females and 57 juveniles from three colonies in central and southern California (San Nicolas, San Miguel, and Año Nuevo Islands). Total Hg concentrations ranged from 0.01 to 0.31 μg g(-1) wet weight (ww) in blood and 0.74 to 21.00 μg g(-1) dry weight (dw) in hair. Adult females had greater mean THg concentrations than juveniles in blood (0.15 vs. 0.03 μg(-1) ww) and hair (10.10 vs. 3.25 μg(-1) dw). Age class differences in THg concentrations did not appear to be driven by trophic level or habitat type because there were no differences in δ (15)N or δ (13)C values between adults and juveniles. Total Hg concentrations in adult females were 54 % (blood) and 24 % (hair) greater in females from San Miguel than females from San Nicolas Island, which may have been because sea lions from the two islands foraged in different areas. For juveniles, we detected some differences in THg concentrations with colony and sex, although these were likely due to sampling effects and not ecological differences. Overall, THg concentrations in California sea lions were within the range documented for other marine mammals and were generally below toxicity benchmarks for fish-eating wildlife.

  19. Effect of a novel mucoadhesive polysaccharide obtained from tamarind seeds on the intraocular penetration of gentamicin and ofloxacin in rabbits.

    PubMed

    Ghelardi, E; Tavanti, A; Celandroni, F; Lupetti, A; Blandizzi, C; Boldrini, E; Campa, M; Senesi, S

    2000-11-01

    This report describes the efficacy of a novel mucoadhesive polymer, the tamarind seed polysaccharide, as a delivery system for the ocular administration of hydrophilic and hydrophobic antibiotics. Healthy rabbits were subjected to repeated ocular instillations with either conventional gentamicin or ofloxacin or these agents viscosified with the tamarind seed polysaccharide. Administration of viscosified preparations produced antibiotic concentrations both in the aqueous humour and cornea that were significantly higher than those achieved with the drugs alone. The increased drug absorption and the prolonged drug elimination phase obtained with the viscosified formulations indicate the usefulness of the tamarind seed polysaccharide as an ophthalmic delivery system for topical administration of antibiotics.

  20. Surface wave effects on water temperature in the Baltic Sea: simulations with the coupled NEMO-WAM model

    NASA Astrophysics Data System (ADS)

    Alari, Victor; Staneva, Joanna; Breivik, Øyvind; Bidlot, Jean-Raymond; Mogensen, Kristian; Janssen, Peter

    2016-08-01

    Coupled circulation (NEMO) and wave model (WAM) system was used to study the effects of surface ocean waves on water temperature distribution and heat exchange at regional scale (the Baltic Sea). Four scenarios—including Stokes-Coriolis force, sea-state dependent energy flux (additional turbulent kinetic energy due to breaking waves), sea-state dependent momentum flux and the combination these forcings—were simulated to test the impact of different terms on simulated temperature distribution. The scenario simulations were compared to a control simulation, which included a constant wave-breaking coefficient, but otherwise was without any wave effects. The results indicate a pronounced effect of waves on surface temperature, on the distribution of vertical temperature and on upwelling's. Overall, when all three wave effects were accounted for, did the estimates of temperature improve compared to control simulation. During the summer, the wave-induced water temperature changes were up to 1 °C. In northern parts of the Baltic Sea, a warming of the surface layer occurs in the wave included simulations in summer months. This in turn reduces the cold bias between simulated and measured data, e.g. the control simulation was too cold compared to measurements. The warming is related to sea-state dependent energy flux. This implies that a spatio-temporally varying wave-breaking coefficient is necessary, because it depends on actual sea state. Wave-induced cooling is mostly observed in near-coastal areas and is the result of intensified upwelling in the scenario, when Stokes-Coriolis forcing is accounted for. Accounting for sea-state dependent momentum flux results in modified heat exchange at the water-air boundary which consequently leads to warming of surface water compared to control simulation.

  1. Effect of acid hydrolysis and fungal biotreatment on agro-industrial wastes for obtainment of free sugars for bioethanol production

    PubMed Central

    El-Tayeb, T.S.; Abdelhafez, A.A.; Ali, S.H.; Ramadan, E.M.

    2012-01-01

    This study was designed to evaluate selected chemical and microbiological treatments for the conversion of certain local agro-industrial wastes (rice straw, corn stalks, sawdust, sugar beet waste and sugarcane bagasse) to ethanol. The chemical composition of these feedstocks was determined. Conversion of wastes to free sugars by acid hydrolysis varied from one treatment to another. In single-stage dilute acid hydrolysis, increasing acid concentration from 1 % (v/v) to 5 % (v/v) decreased the conversion percentage of almost all treated agro-industrial wastes. Lower conversion percentages for some treatments were obtained when increasing the residence time from 90 to 120 min. The two-stage dilute acid hydrolysis by phosphoric acid (1.0 % v/v) followed by sulphuric acid (1.0 % v/v) resulted in the highest conversion percentage (41.3 % w/w) on treated sugar beet waste. This treatment when neutralized, amended with some nutrients and inoculated with baker’s yeast, achieved the highest ethanol concentration (1.0 % v/v). Formation of furfural and hydroxymethylfurfural (HMF) were functions of type of acid hydrolysis, acid concentration, residence time and feedstock type. The highest bioconversion of 5 % wastes (37.8 % w/w) was recorded on sugar beet waste by Trichoderma viride EMCC 107. This treatment when followed by baker’s yeast fermentation, 0.41 % (v/v) ethanol and 8.2 % (v/w) conversion coefficient were obtained. PMID:24031984

  2. Effect of acid hydrolysis and fungal biotreatment on agro-industrial wastes for obtainment of free sugars for bioethanol production.

    PubMed

    El-Tayeb, T S; Abdelhafez, A A; Ali, S H; Ramadan, E M

    2012-10-01

    This study was designed to evaluate selected chemical and microbiological treatments for the conversion of certain local agro-industrial wastes (rice straw, corn stalks, sawdust, sugar beet waste and sugarcane bagasse) to ethanol. The chemical composition of these feedstocks was determined. Conversion of wastes to free sugars by acid hydrolysis varied from one treatment to another. In single-stage dilute acid hydrolysis, increasing acid concentration from 1 % (v/v) to 5 % (v/v) decreased the conversion percentage of almost all treated agro-industrial wastes. Lower conversion percentages for some treatments were obtained when increasing the residence time from 90 to 120 min. The two-stage dilute acid hydrolysis by phosphoric acid (1.0 % v/v) followed by sulphuric acid (1.0 % v/v) resulted in the highest conversion percentage (41.3 % w/w) on treated sugar beet waste. This treatment when neutralized, amended with some nutrients and inoculated with baker's yeast, achieved the highest ethanol concentration (1.0 % v/v). Formation of furfural and hydroxymethylfurfural (HMF) were functions of type of acid hydrolysis, acid concentration, residence time and feedstock type. The highest bioconversion of 5 % wastes (37.8 % w/w) was recorded on sugar beet waste by Trichoderma viride EMCC 107. This treatment when followed by baker's yeast fermentation, 0.41 % (v/v) ethanol and 8.2 % (v/w) conversion coefficient were obtained. PMID:24031984

  3. Effect of aggregation of horn fly populations within cattle herds and consequences for sampling to obtain unbiased estimates of abundance.

    PubMed

    Lysyk, T J; Steelman, C D

    2004-07-01

    Reanalysis of counts of horn fly, Hematobia irritans (L.), obtained from a variety of cattle herds indicated that aggregation of the flies within herds decreased as mean fly density increased. Aggregation was also related to the proportion of fly-resistant and fly-susceptible cattle in a herd. Herds were grouped according to their degree of horn fly aggregation. Low aggregation herds included larger framed Angus, Horned Hereford, Polled Hereford, and Red Poll breeds. Moderate aggregation occurred with Brahman, Charolais, small-framed Angus, mixed cows, and Hereford x Charolais cross. High aggregation occurred with Chianina and mixed herds. Relationships between the sample means and variances varied among aggregation groups. A resampling approach was used to determine the influence of random sampling of a herd on the proportion of horn fly population estimates within fixed percentages of the true mean. The proportion of sample means within +/- 5, 10, 15, and 20% of the true means varied with the proportion of the herd sampled, the mean and variance of fly density, and herd size. Recommendations for obtaining sample size to estimate fly density within a fixed percentage of the true mean are given.

  4. Effect of aggregation of horn fly populations within cattle herds and consequences for sampling to obtain unbiased estimates of abundance.

    PubMed

    Lysyk, T J; Steelman, C D

    2004-07-01

    Reanalysis of counts of horn fly, Hematobia irritans (L.), obtained from a variety of cattle herds indicated that aggregation of the flies within herds decreased as mean fly density increased. Aggregation was also related to the proportion of fly-resistant and fly-susceptible cattle in a herd. Herds were grouped according to their degree of horn fly aggregation. Low aggregation herds included larger framed Angus, Horned Hereford, Polled Hereford, and Red Poll breeds. Moderate aggregation occurred with Brahman, Charolais, small-framed Angus, mixed cows, and Hereford x Charolais cross. High aggregation occurred with Chianina and mixed herds. Relationships between the sample means and variances varied among aggregation groups. A resampling approach was used to determine the influence of random sampling of a herd on the proportion of horn fly population estimates within fixed percentages of the true mean. The proportion of sample means within +/- 5, 10, 15, and 20% of the true means varied with the proportion of the herd sampled, the mean and variance of fly density, and herd size. Recommendations for obtaining sample size to estimate fly density within a fixed percentage of the true mean are given. PMID:15311450

  5. Assessing assessment: Can the expected effects of the St. Marys River sea lamprey control strategy be detected?

    USGS Publications Warehouse

    Adams, Jean V.; Bergstedt, Roger A.; Christie, Gavin C.; Cuddy, Douglas W.; Fodale, Michael F.; Heinrich, John W.; Jones, Michael L.; McDonald, Rodney B.; Mullett, Katherine M.; Young, Robert J.

    2003-01-01

    In 1997 the Great Lakes Fishery Commission approved a 5-year (1998 to 2002) control strategy to reduce sea lamprey (Petromyzon marinus) production in the St. Marys River, the primary source of parasitic sea lampreys in northern Lake Huron. An assessment plan was developed to measure the success of the control strategy and decide on subsequent control efforts. The expected effects of the St. Marys River control strategy are described, the assessments in place to measure these effects are outlined, and the ability of these assessments to detect the expected effects are quantified. Several expected changes were predicted to be detectable: abundance of parasitic-phase sea lampreys and annual mortality of lake trout (Salvelinus namaycush) by 2001, abundance of spawning-phase sea lampreys by 2002, and relative return rates of lake trout and sea lamprey wounding rates on lake trout by 2005. Designing an effective assessment program to quantify the consequences of fishery management actions is a critical, but often overlooked ingredient of sound fisheries management.

  6. An inquiry into the concept of SEA effectiveness: Towards criteria for Chinese practice

    SciTech Connect

    Bina, Olivia; Jing Wu; Brown, Lex; Partidario, Maria Rosario

    2011-11-15

    The importance of improving the effectiveness of Plan EIA and SEA-type evaluations in China cannot be overstated: at a time when the country's economy is being boosted by a stimulus package worth over RMB 400 trillion - largely for infrastructure - the pressure on China's already strained environment and resource base is bound to increase. The aim is to propose the criteria for plan EIA's effectiveness to raise the awareness of the need to strengthen the performance of the assessment and maximize its potential benefits. The authors first review critically the discourse on the effectiveness of the impact assessment, identifying three dimensions: substantive, procedural and incremental. The resulting conceptual framework allows them to interpret the weaknesses of the Chinese discourse on the effectiveness and of the practice of the Plan EIA to date. The result is the identification of a clear gap, both in terms of the breadth of the concept, and in terms of the quality of the existing criteria, which tend to be very generic to the point of inapplicability. The analysis also reveals a need for transitioning from formal models of the Plan EIA to more strategic approaches, in a gradual manner that is consistent with context-specificities. The proposal of a set of preliminary criteria for effectiveness is therefore structured on three levels. This framework is meant to input into the ongoing debate on how to improve the practice of PEIA and the SEA-type evaluations in China, and provide ideas for a government strategy aimed at maximizing the positive impact of PEIAs on planning, as well as on the context of application.

  7. The dynamic nature of relative sea level in Southeast Asia: tectonic effects and human impacts (Invited)

    NASA Astrophysics Data System (ADS)

    Hill, E.; Qiu, Q.; Feng, L.; Lubis, A.; Meltzner, A. J.; Tsang, L. L.; Daly, P.; McCaughey, J.; Banerjee, P.; Rubin, C. M.; Sieh, K.

    2013-12-01

    Tectonic changes can have significant effects on crustal deformation, the geoid, and relative sea level (RSL). Indeed, the tectonic impacts on RSL in some regions can be greater than those predicted as a result of climate change. In the case of earthquakes, these changes can occur suddenly, as coastlines uplift or subside by up to many meters. The changes can also occur over many decades as a result of interseismic or postseismic processes, or periodically in the form of transient slow-slip events. Although these effects are (mostly) recovered elastically over the course of the earthquake cycle, they are occurring in the context of ever-increasing populations living along affected coastlines, particularly the case in areas such as SE Asia. The societal effects of these tectonic-induced sea-level changes are therefore becoming increasingly significant, and important to consider in future projections for sea-level change. Additionally, tide-gauge and gravity measurements made in tectonically active areas cannot be interpreted without consideration and modeling of the tectonic setting. These facts highlight the need for accurate geodetic measurements of land-height change. Along the Sumatra subduction zone, a series of great earthquakes have occurred over the last decade, along with numerous moderate and smaller earthquakes. These, and their ensuing postseismic deformation, have reshaped regional coastlines. We will show visualization of land height changes using a decade of Sumatra GPS Array (SuGAr) data, and related tectonic models, that demonstrate dramatically the ups and downs of land elevation close to the earthquake sources. Vertical coseismic displacements as large as ~2.9 m have been recorded by the SuGAr (an uplift at Nias, during the 2005 Mw 8.6 earthquake), and vertical postseismic rates on the order of tens of mm/yr or greater (e.g., in northern Aceh, one station has been uplifting at a rate of ~34 mm/yr since the 2004 Mw 9.2 earthquake, while in southern

  8. Effect of sea-level rise on salt water intrusion near a coastal well field in southeastern Florida.

    PubMed

    Langevin, Christian D; Zygnerski, Michael

    2013-01-01

    A variable-density groundwater flow and dispersive solute transport model was developed for the shallow coastal aquifer system near a municipal supply well field in southeastern Florida. The model was calibrated for a 105-year period (1900 to 2005). An analysis with the model suggests that well-field withdrawals were the dominant cause of salt water intrusion near the well field, and that historical sea-level rise, which is similar to lower-bound projections of future sea-level rise, exacerbated the extent of salt water intrusion. Average 2005 hydrologic conditions were used for 100-year sensitivity simulations aimed at quantifying the effect of projected rises in sea level on fresh coastal groundwater resources near the well field. Use of average 2005 hydrologic conditions and a constant sea level result in total dissolved solids (TDS) concentration of the well field exceeding drinking water standards after 70 years. When sea-level rise is included in the simulations, drinking water standards are exceeded 10 to 21 years earlier, depending on the specified rate of sea-level rise.

  9. Effect of Bacillus baekryungensis YD13 supplemented in diets on growth performance and immune response of sea cucumber ( Apostichopus japonicus)

    NASA Astrophysics Data System (ADS)

    Yan, Fajun; Tian, Xiangli; Dong, Shuanglin

    2014-10-01

    The effect of a potential probiotic on the growth performance and immune response of sea cucumber ( Apostichopus japonicus) was investigated. Bacillus baekryungensis YD13 isolated from sea cucumber culturing ponds was added to sea cucumber basal feed as a probiotic in different doses (0, the control; 1×104 (YD134), 1×106 (YD136) and 1×108 (YD138) CFU g-1 of diet), and administered orally to A. japonicus (initial mean wet weight 5.44 g ± 0.17 g). The sea cucumbers were fed in 20 aquaria, 5 each treatment, for 60 d. At the end of growth trial, 20 sea cucumbers from each treatment were challenged with Vibrio splendidus. A. japonicus in YD134 and YD136 exhibited significantly better growth performance than control ( P < 0.05). Five non-specific immune parameters including lysozyme, acid phosphatase, alkaline phosphatase, superoxide dismutase and catalase in coelomic fluid were measured to evaluate the immune response of A. japonicus to the probiotics. Results showed that all parameters were significantly improved when YD11 was supplemented in the dose of 1×106 CFU g-1 ( P < 0.05). The cumulative incidence and mortality after the Vibrio splendidus challenge decreased significantly in sea cucumbers of YD136. Accordingly, 1×106 CFU g-1 of YD13 in diet was recommended for the growth promotion and immune enhancement of A. japonicus.

  10. Effects of sea-level rise on salt water intrusion near a coastal well field in southeastern Florida

    USGS Publications Warehouse

    Langevin, Christian D.; Zygnerski, Michael

    2013-01-01

    A variable-density groundwater flow and dispersive solute transport model was developed for the shallow coastal aquifer system near a municipal supply well field in southeastern Florida. The model was calibrated for a 105-year period (1900 to 2005). An analysis with the model suggests that well-field withdrawals were the dominant cause of salt water intrusion near the well field, and that historical sea-level rise, which is similar to lower-bound projections of future sea-level rise, exacerbated the extent of salt water intrusion. Average 2005 hydrologic conditions were used for 100-year sensitivity simulations aimed at quantifying the effect of projected rises in sea level on fresh coastal groundwater resources near the well field. Use of average 2005 hydrologic conditions and a constant sea level result in total dissolved solids (TDS) concentration of the well field exceeding drinking water standards after 70 years. When sea-level rise is included in the simulations, drinking water standards are exceeded 10 to 21 years earlier, depending on the specified rate of sea-level rise.

  11. The seasonal appearance of ice shelf water in coastal Antarctica and its effect on sea ice growth

    NASA Astrophysics Data System (ADS)

    Mahoney, Andrew R.; Gough, Alexander J.; Langhorne, Patricia J.; Robinson, Natalie J.; Stevens, Craig L.; Williams, Michael M. J.; Haskell, Timothy G.

    2011-11-01

    In this paper we report measurements from the first year-round mooring underneath sea ice in McMurdo Sound, Antarctica, which we combine with full-depth ocean profiles to identify the incremental appearance of potentially supercooled ice shelf water (ISW). We investigate the effects of ISW on sea ice using observations of sea ice growth and crystal structure together with under-ice photography. We show that the appearance of ISW at the surface leads to a disruption in the columnar texture of the sea ice, but that persistent growth enhancement occurs only once the entire water column has cooled to the surface freezing point. In doing so, we demonstrate the possibility of inferring the presence of ISW beneath sea ice through crystallographic analysis of cores. These findings will be useful for both modeling and observing the extent of ISW-enhanced ice growth. In addition, we found that the local growth of first-year landfast sea ice only accounted for half of the observed increase in salinity over the water column, which indicates that polynyas are responsible for approximately half of the salt flux into McMurdo Sound.

  12. Biological effect of low-head sea lamprey barriers: Designs for extensive surveys and the value of incorporating intensive process-oriented research

    USGS Publications Warehouse

    Hayes, D.B.; Baylis, J.R.; Carl, L.M.; Dodd, H.R.; Goldstein, J.D.; McLaughlin, R.L.; Noakes, D.L.G.; Porto, L.M.

    2003-01-01

    Four sampling designs for quantifying the effect of low-head sea lamprey (Petromyzon marinus) barriers on fish communities were evaluated, and the contribution of process-oriented research to the overall confidence of results obtained was discussed. The designs include: (1) sample barrier streams post-construction; (2) sample barrier and reference streams post-construction; (3) sample barrier streams pre- and post-construction; and (4) sample barrier and reference streams pre- and post-construction. In the statistical literature, the principal basis for comparison of sampling designs is generally the precision achieved by each design. In addition to precision, designs should be compared based on the interpretability of results and on the scale to which the results apply. Using data collected in a broad survey of streams with and without sea lamprey barriers, some of the tradeoffs that occur among precision, scale, and interpretability are illustrated. Although circumstances such as funding and availability of pre-construction data may limit which design can be implemented, a pre/post-construction design including barrier and reference streams provides the most meaningful information for use in barrier management decisions. Where it is not feasible to obtain pre-construction data, a design including reference streams is important to maintain the interpretability of results. Regardless of the design used, process-oriented research provides a framework for interpreting results obtained in broad surveys. As such, information from both extensive surveys and intensive process-oriented research provides the best basis for fishery management actions, and gives researchers and managers the most confidence in the conclusions reached regarding the effects of sea lamprey barriers.

  13. Evaluation of the swell effect on the air-sea gas transfer in the coastal zone

    NASA Astrophysics Data System (ADS)

    Gutiérrez-Loza, Lucía; Ocampo-Torres, Francisco J.

    2016-04-01

    Air-sea gas transfer processes are one of the most important factors regarding global climate and long-term global climate changes. Despite its importance, there is still a huge uncertainty on how to better parametrize these processes in order to include them on the global climate models. This uncertainty exposes the need to increase our knowledge on gas transfer controlling mechanisms. In the coastal regions, breaking waves become a key factor to take into account when estimating gas fluxes, however, there is still a lack of information and the influence of the ocean surface waves on the air-sea interaction and gas flux behavior must be validated. In this study, as part of the "Sea Surface Roughness as Air-Sea Interaction Control" project, we evaluate the effect of the ocean surface waves on the gas exchange in the coastal zone. Direct estimates of the flux of CO2 (FCO2) and water vapor (FH2O) through eddy covariance, were carried out from May 2014 to April 2015 in a coastal station located at the Northwest of Todos Santos Bay, Baja California, México. For the same period, ocean surface waves are recorded using an Acoustic Doppler Current Profiler (Workhorse Sentinel, Teledyne RD Instruments) with a sampling rate of 2 Hz and located at 10 m depth about 350 m away from the tower. We found the study area to be a weak sink of CO2 under moderate wind and wave conditions with a mean flux of -1.32 μmol/m2s. The correlation between the wind speed and FCO2 was found to be weak, suggesting that other physical processes besides wind may be important factors for the gas exchange modulation at coastal waters. The results of the quantile regression analysis computed between FCO2 and (1) wind speed, (2) significant wave height, (3) wave steepness and (4) water temperature, show that the significant wave height is the most correlated parameter with FCO2; Nevertheless, the behavior of their relation varies along the probability distribution of FCO2, with the linear regression

  14. Global modelling of direct and indirect effects of sea spray aerosol using a source function encapsulating wave state

    NASA Astrophysics Data System (ADS)

    Partanen, A.-I.; Dunne, E. M.; Bergman, T.; Laakso, A.; Kokkola, H.; Ovadnevaite, J.; Sogacheva, L.; Baisnée, D.; Sciare, J.; Manders, A.; O'Dowd, C.; de Leeuw, G.; Korhonen, H.

    2014-11-01

    Recently developed parameterizations for the sea spray aerosol source flux, encapsulating wave state, and its organic fraction were incorporated into the aerosol-climate model ECHAM-HAMMOZ to investigate the direct and indirect radiative effects of sea spray aerosol particles. Our simulated global sea salt emission of 805 Tg yr-1 (uncertainty range 378-1233 Tg yr-1) was much lower than typically found in previous studies. Modelled sea salt and sodium ion concentrations agreed relatively well with measurements in the smaller size ranges at Mace Head (annual normalized mean model bias -13% for particles with vacuum aerodynamic diameter Dva < 1 μm), Point Reyes (-29% for particles with aerodynamic diameter Da < 2.5 μm) and Amsterdam Island (-52% for particles with Da < 1 μm) but the larger sizes were overestimated (899% for particles with 2.5 μm < Da < 10 μm) at Amsterdam Island. This suggests that at least the high end of the previous estimates of sea spray mass emissions is unrealistic. On the other hand, the model clearly underestimated the observed concentrations of organic or total carbonaceous aerosol at Mace Head (-82%) and Amsterdam Island (-68%). The large overestimation (212%) of organic matter at Point Reyes was due to the contribution of continental sources. At the remote Amsterdam Island site, the organic concentration was underestimated especially in the biologically active months, suggesting a need to improve the parameterization of the organic sea spray fraction. Globally, the satellite-retrieved AOD over the oceans, using PARASOL data, was underestimated by the model (means over ocean 0.16 and 0.10, respectively); however, in the pristine region around Amsterdam Island the measured AOD fell well within the simulated uncertainty range. The simulated sea spray aerosol contribution to the indirect radiative effect was positive (0.3 W m-2), in contrast to previous studies. This positive effect was ascribed to the tendency of sea salt aerosol to

  15. Global modelling of direct and indirect effects of sea spray aerosol using a source function encapsulating wave state

    NASA Astrophysics Data System (ADS)

    Partanen, A.-I.; Dunne, E. M.; Bergman, T.; Laakso, A.; Kokkola, H.; Ovadnevaite, J.; Sogacheva, L.; Baisnée, D.; Sciare, J.; Manders, A.; O'Dowd, C.; de Leeuw, G.; Korhonen, H.

    2014-02-01

    Recently developed parameterizations for the sea spray aerosol source flux, encapsulating wave state, and its organic fraction were incorporated into the aerosol-climate model ECHAM-HAMMOZ to investigate the direct and indirect radiative effects of sea spray aerosol particles. Our simulated global sea salt emission of 805 Tg yr-1 (uncertainty range 378-1233 Tg yr-1) was much lower than typically found in previous studies. Modelled sea salt and sodium ion concentrations agreed relatively well with measurements in the smaller size ranges at Mace Head (annual normalized mean model bias -13% for particles with vacuum aerodynamic diameter Dva < 1 μm), Point Reyes (-29% for particles with aerodynamic diameter Da < 2.5 μm) and Amsterdam Island (-52% for particles with Da < 1 μm) but the larger sizes were overestimated (899% for particles with 2.5 μm sea spray mass emissions is unrealistic. On the other hand, the model clearly underestimated the observed concentrations of organic or total carbonaceous aerosol at Mace Head (-82%) and Amsterdam Island (-68%). The large overestimation (212%) of organic matter at Point Reyes was due to the contribution of continental sources. At the remote Amsterdam Island site, the organic concentration was underestimated especially in the biologically active months, suggesting a need to improve the parameterization of the organic sea spray fraction. Globally, the satellite-retrieved AOD over the oceans, using PARASOL data, was underestimated by the model (means over ocean 0.16 and 0.10, respectively); however, in the pristine region around Amsterdam Island the measured AOD fell well within the simulated uncertainty range. The simulated sea spray aerosol contribution to the indirect radiative effect was positive (0.3 W m-2), in contrast to previous studies. This positive effect was ascribed to the tendency of sea salt aerosol to

  16. Effect of cervical relining of acrylic resin copings on the accuracy of stone dies obtained using a polyether impression material.

    PubMed

    de Sá, André Tomazini Gomes; de Freitas, César Antunes; de Sá, Fátima Cristina; Ursi, Wagner José Silva; Simões, Tânia Christina; de Freitas, Márcia Furtado Antunes

    2008-01-01

    The purpose of this study was to evaluate the accuracy of the respective dies after polyether elastomeric procedure in the presence or absence of cervical contact of the acrylic resin shell with the cervical region, establishing a comparison to dies obtained with stock trays. This study consisted of three groups with 10 specimens each: 1) acrylic copings without cervical contact, (cn); 2) acrylic copings with cervical contact (cc); 3) perforated stock tray, (st). The accuracy of the resulting dies was verified with the aid of a master crown, precisely fit to the master steel die. ANOVA test found statistically significant differences among groups (p<0.001). Tukey's test found that the smallest discrepancy occurred in group cn, followed by cc, while the st group presented the highest difference (cc x cn: p=0.007; st x cn: p<0.001; st x cc: p<0.001).

  17. How effective is albedo modification (solar radiation management geoengineering) in preventing sea-level rise from the Greenland Ice Sheet?

    NASA Astrophysics Data System (ADS)

    Applegate, Patrick J.; Keller, Klaus

    2015-08-01

    Albedo modification (AM) is sometimes characterized as a potential means of avoiding climate threshold responses, including large-scale ice sheet mass loss. Previous work has investigated the effects of AM on total sea-level rise over the present century, as well as AM’s ability to reduce long-term (≫103 yr) contributions to sea-level rise from the Greenland Ice Sheet (GIS). These studies have broken new ground, but neglect important feedbacks in the GIS system, or are silent on AM’s effectiveness over the short time scales that may be most relevant for decision-making (<103 yr). Here, we assess AM’s ability to reduce GIS sea-level contributions over decades to centuries, using a simplified ice sheet model. We drive this model using a business-as-usual base temperature forcing scenario, as well as scenarios that reflect AM-induced temperature stabilization or temperature drawdown. Our model results suggest that (i) AM produces substantial near-term reductions in the rate of GIS-driven sea-level rise. However, (ii) sea-level rise contributions from the GIS continue after AM begins. These continued sea level rise contributions persist for decades to centuries after temperature stabilization and temperature drawdown begin, unless AM begins in the next few decades. Moreover, (iii) any regrowth of the GIS is delayed by decades or centuries after temperature drawdown begins, and is slow compared to pre-AM rates of mass loss. Combined with recent work that suggests AM would not prevent mass loss from the West Antarctic Ice Sheet, our results provide a nuanced picture of AM’s possible effects on future sea-level rise.

  18. The effect of hexose ratios on metabolite production in Saccharomyces cerevisiae strains obtained from the spontaneous fermentation of mezcal.

    PubMed

    Oliva Hernández, Amanda A; Taillandier, Patricia; Reséndez Pérez, Diana; Narváez Zapata, José A; Larralde Corona, Claudia Patricia

    2013-04-01

    Mezcal from Tamaulipas (México) is produced by spontaneous alcoholic fermentation using Agave spp. musts, which are rich in fructose. In this study eight Saccharomyces cerevisiae isolates obtained at the final stage of fermentation from a traditional mezcal winery were analysed in three semi-synthetic media. Medium M1 had a sugar content of 100 g l(-1) and a glucose/fructose (G/F) of 9:1. Medium M2 had a sugar content of 100 g l(-1) and a G/F of 1:9. Medium M3 had a sugar content of 200 g l(-1) and a G/F of 1:1. In the three types of media tested, the highest ethanol yield was obtained from the glucophilic strain LCBG-3Y5, while strain LCBG-3Y8 was highly resistant to ethanol and the most fructophilic of the mezcal strains. Strain LCBG-3Y5 produced more glycerol (4.4 g l(-1)) and acetic acid (1 g l(-1)) in M2 than in M1 (1.7 and 0.5 g l(-1), respectively), and the ethanol yields were higher for all strains in M1 except for LCBG-3Y5, -3Y8 and the Fermichamp strain. In medium M3, only the Fermichamp strain was able to fully consume the 100 g of fructose l(-1) but left a residual 32 g of glucose l(-1). Regarding the hexose transporters, a high number of amino acid polymorphisms were found in the Hxt1p sequences. Strain LCBG-3Y8 exhibited eight unique amino acid changes, followed by the Fermichamp strain with three changes. In Hxt3p, we observed nine amino acid polymorphisms unique for the Fermichamp strain and five unique changes for the mezcal strains. PMID:23271642

  19. The effect of hexose ratios on metabolite production in Saccharomyces cerevisiae strains obtained from the spontaneous fermentation of mezcal.

    PubMed

    Oliva Hernández, Amanda A; Taillandier, Patricia; Reséndez Pérez, Diana; Narváez Zapata, José A; Larralde Corona, Claudia Patricia

    2013-04-01

    Mezcal from Tamaulipas (México) is produced by spontaneous alcoholic fermentation using Agave spp. musts, which are rich in fructose. In this study eight Saccharomyces cerevisiae isolates obtained at the final stage of fermentation from a traditional mezcal winery were analysed in three semi-synthetic media. Medium M1 had a sugar content of 100 g l(-1) and a glucose/fructose (G/F) of 9:1. Medium M2 had a sugar content of 100 g l(-1) and a G/F of 1:9. Medium M3 had a sugar content of 200 g l(-1) and a G/F of 1:1. In the three types of media tested, the highest ethanol yield was obtained from the glucophilic strain LCBG-3Y5, while strain LCBG-3Y8 was highly resistant to ethanol and the most fructophilic of the mezcal strains. Strain LCBG-3Y5 produced more glycerol (4.4 g l(-1)) and acetic acid (1 g l(-1)) in M2 than in M1 (1.7 and 0.5 g l(-1), respectively), and the ethanol yields were higher for all strains in M1 except for LCBG-3Y5, -3Y8 and the Fermichamp strain. In medium M3, only the Fermichamp strain was able to fully consume the 100 g of fructose l(-1) but left a residual 32 g of glucose l(-1). Regarding the hexose transporters, a high number of amino acid polymorphisms were found in the Hxt1p sequences. Strain LCBG-3Y8 exhibited eight unique amino acid changes, followed by the Fermichamp strain with three changes. In Hxt3p, we observed nine amino acid polymorphisms unique for the Fermichamp strain and five unique changes for the mezcal strains.

  20. Potentiation of antifungal effect of a mixture of two antifungal fractions obtained from Baccharis glutinosa and Jacquinia macrocarpa plants.

    PubMed

    Medina-López, Carlos F; Plascencia-Jatomea, Maribel; Cinco-Moroyoqui, Francisco J; Yépiz-Gómez, María S; Cortez-Rocha, Mario O; Rosas-Burgos, Ema C

    2016-11-01

    The aim of the present work was to evaluate the effect of mixtures of antifungal fractions extracted from Baccharis glutinosa and Jacquinia macrocarpa plants on the development of the filamentous fungi Aspergillus flavus and Fusarium verticillioides. The minimal inhibitory concentration that inhibited 50% of growth (MIC50) of each plant antifungal fraction was determined from the percentage radial growth inhibition of both fungi. Binomial mixtures made with both plant fractions were used at their MIC50 to determine the Fractional Inhibitory Concentration index (FIC index) for each fungus in order to evaluate their synergistic effect. Each synergistic mixture was analyzed in their effect on spore germination, spore size, spore viability, mitotic divisions, hyphal diameter and length, and number of septa per hypha. Some antifungal mixtures, even at low concentrations, showed higher antifungal effect than those of the individual antifungal fraction. The FIC indices of mixtures that showed the highest antifungal activity against A. flavus and F. verticillioides were 0.5272 and 0.4577, respectively, indicating a synergistic effect against both fungi. Only 12% and 8% of the spores of A. flavus and F. verticillioides, respectively, treated with the synergistic mixtures, were able to germinate, although their viability was not affected. An increase in the number of septa per hypha of both fungi was observed. The results indicated that the synergistic mixtures strongly affected the fungal growth even at lower concentrations than those of the individual plant fractions. PMID:27382921

  1. Sea Level Rise and Climate Change Effects on Marsh Plants Spartina Alterniflora and Typha Angustifolia Using Mesocosms

    EPA Science Inventory

    A four month experiment using greenhouse mesocosms was conducted to analyze the effect of sea level rise and climate change on salt marsh plants Spartina alterniflora (cordgrass) and Typha angustifolia (narrow-leaved cattail). Our goal was to examine the effects of three differen...

  2. Effects of pressure on the dynamics of an oligomeric protein from deep-sea hyperthermophile.

    PubMed

    Shrestha, Utsab R; Bhowmik, Debsindhu; Copley, John R D; Tyagi, Madhusudan; Leão, Juscelino B; Chu, Xiang-qiang

    2015-11-10

    Inorganic pyrophosphatase (IPPase) from Thermococcus thioreducens is a large oligomeric protein derived from a hyperthermophilic microorganism that is found near hydrothermal vents deep under the sea, where the pressure is up to 100 MPa (1 kbar). It has attracted great interest in biophysical research because of its high activity under extreme conditions in the seabed. In this study, we use the quasielastic neutron scattering (QENS) technique to investigate the effects of pressure on the conformational flexibility and relaxation dynamics of IPPase over a wide temperature range. The β-relaxation dynamics of proteins was studied in the time ranges from 2 to 25 ps, and from 100 ps to 2 ns, using two spectrometers. Our results indicate that, under a pressure of 100 MPa, close to that of the native environment deep under the sea, IPPase displays much faster relaxation dynamics than a mesophilic model protein, hen egg white lysozyme (HEWL), at all measured temperatures, opposite to what we observed previously under ambient pressure. This contradictory observation provides evidence that the protein energy landscape is distorted by high pressure, which is significantly different for hyperthermophilic (IPPase) and mesophilic (HEWL) proteins. We further derive from our observations a schematic denaturation phase diagram together with energy landscapes for the two very different proteins, which can be used as a general picture to understand the dynamical properties of thermophilic proteins under pressure.

  3. Effect of Machine Learning Techniques on SeaQuest Physics Analyses

    NASA Astrophysics Data System (ADS)

    Morton, Daniel; University of Michigan Ann ArborSeaQuest Collaboration

    2016-03-01

    Fermilab E906, SeaQuest, implements a 120 GeV proton beam from the Main Injector incident on liquid Deuterium and Hydrogen targets and solid Tungsten, Carbon and Iron targets to produce leptons through the Drell-Yan process. Produced particles impinge on an iron beam dump, which absorbs all but muons and neutrinos. Muon pairs are divided and refocused with two dipole magnets. The primary objective is the extraction of the d / u ratio from the muon production cross section ratio σ (d + p) / σ (p + p) . The SeaQuest spectrometer is optimized to search for coincident dimuons, utilizing four detector stations containing scintillators, drift chambers and proportional tubes. The experiment relies on hodoscope coincidence to determine whether to accept the event. The goal of implementing machine learning algorithms (MLAs) is to improve trigger purity and event classification accuracy on both trigger and reconstruction levels, and thus improve statistical precision in all physics analyses and provide insight into spectrometer acceptance bias as well as potentially providing essential trigger optimization for the search of a dark Higgs candidate. We will report on the present status and plans to implement MLAs into the various triggers and its effect on physics analyses.

  4. Effect of dietary herbal supplements on some physiological conditions of Sea Bass Dicentrarchus labrax.

    PubMed

    Yilmaz, Sevdan; Ergun, Sebahattin; Celik, Ekrem Sanver

    2013-06-01

    This study was conducted in order to investigate the effects of dietary thyme Thymus vulgaris, rosemary Rosmarinus officinalis,and fenugreek Trigonella foenum graecum as feed additives on total liver fat levels and biometric indices of Sea Bass Dicentrarchus labrax. Four isonitrogenous (48% crude protein) and isocaloric(21 kJ/g) diets were formulated to contain 0% (control), or 1% of thyme, rosemary, or fenugreek. In a 45-d feeding trial, 12 fiberglass tanks (140 L) were each stocked with 17 fish (20.43 ± 0.03 g).Herbal supplemented diets significantly decreased the total liver fat, visceral fat index, viscerosomatic index, hepatosomatic index,and increased the spleen–somatic index and bile–somatic index(P<0.05). In conclusion, the results indicated that a dietary level of1.0% for thyme, rosemary, or fenugreek could improve some of the physiological parameters of Sea Bass. Thus, this work provides anew perspective for the use of medicinal herbs that can be added to fish feed to improve the status of fish organs. Thyme, rosemary, and fenugreek contain a number of different active components, which possibly play an important role in improving these conditions, but the mechanism by which this is achieved needs further and more detailed study.

  5. Environmental hazard of yperite released at sea: sublethal toxic effects on fish.

    PubMed

    Della Torre, Camilla; Petochi, Tommaso; Farchi, Cristina; Corsi, Ilaria; Dinardo, Maria Maddalena; Sammarini, Valerio; Alcaro, Luigi; Mechelli, Luca; Focardi, Silvano; Tursi, Angelo; Marino, Giovanna; Amato, Ezio

    2013-03-15

    The aim of this study was to evaluate the potential toxicological effects on fish related to the leakage of yperite from rusted bomb shells dumped at sea. Both in vivo and field studies have been performed. As for the in vivo experiment, specimen of European eel were subcutaneously injected with 0.015, 0.15 and 1.5mg/kg of yperite and sacrificed after 24 and 48 h. In the field study, specimen of Conger eel were collected from a dumping site in the Southern Adriatic Sea. The presence/absence of yperite in tissues, genotoxicity, detoxification enzymes, histological alterations and gross abnormalities were investigated. Results of the in vivo experiment showed a significant increase of EROD activity at both 24h and 48 h. UGT activity increased significantly at 48 h post injection. An acute inflammatory response after 24h in skin layers and muscle was observed, associated to cell degeneration and necrosis after 48 h at the highest dose. On field, comet assay revealed genotoxicity in gills of fish from the dumping site. Specimen from the dumping site showed significantly higher EROD activities compared to controls, deep ulcers and papules on skin together with liver and spleen histopathological lesions. PMID:23380450

  6. Effects of the Changjiang (Yangtze) River discharge on planktonic community respiration in the East China Sea

    NASA Astrophysics Data System (ADS)

    Chen, Chung-Chi; Shiah, Fuh-Kwo; Chiang, Kuo-Ping; Gong, Gwo-Ching; Kemp, W. Michael

    2009-03-01

    Planktonic communities tend to flourish on the western margins of the East China Sea (ECS) fueled by substrates delivered largely from the Changjiang River, the fifth largest river in the world. To study the effects of the Changjiang River discharge on planktonic community respiration (CR), physical-chemical variables and key processes were measured in three consecutive summers in the ECS. Results showed that concentrations of nitrate and Chl a, protozoan biomass, bacterial production, as well as CR in the surface water were all negatively correlated with sea surface salinity, reflecting the strong influence of river discharge on the ECS shelf ecosystem. Moreover, mean values of nitrate, Chl a concentrations, and CR rates were proportionally related to the area of Changjiang diluted water (CDW; salinity ≤31.0 practical salinity units (psu)), an index of river discharge rate. Presumably, higher river flow delivers higher nutrient concentrations which stimulate phytoplankton growth, which in turn fuels CR. CR exhibited significant monthly and interannual variability, and rates appear to be dominated by bacteria and phytoplankton. Although the plankton community was relatively productive (mean = 0.8 mg C m-2 d-1) in the CDW, the mean ratio of production to respiration was low (0.42). This suggests that the heterotrophic processes regulating CR were supported by riverine organic carbon input in addition to in situ autotrophic production.

  7. The effect of Holocene changes in relative sea level on the morphology of rocky coasts

    NASA Astrophysics Data System (ADS)

    Trenhaile, Alan S.

    2010-01-01

    A mathematical wave and weathering model was used to study the effect of Holocene changes in relative sea level (RSL) on rock coast development. Model runs were made for fast- and slow-eroding coasts in macro- and mesotidal environments using Holocene RSL records from Sweden, northeastern USA, southwestern Britain, central Japan, western Africa, and southern Australia. A further series of otherwise identical runs were made with constant sea level. Changes in RSL determined the amount of time that marine processes have operated within the modern intertidal zone, and rates of wave attenuation and erosion continue to be influenced by subtidal morphology that developed in most areas when RSL was rising to its present level. The model suggested that although tidal range is also important, Holocene RSL changes promoted subhorizontal platform development in Australasia and over much of the Southern Hemisphere, and sloping platforms over much of the Northern Hemisphere. Shore platforms may have been partly inherited from earlier periods in the Holocene, when RSL was similar to today's. Nevertheless, most platforms continue to be eroded at all tidal levels. Where geological and wave conditions are less favourable, erosion in the lower intertidal zone has essentially terminated in areas where RSL rose to its present position, whereas erosion only occurs today in the lower intertidal zone in places where RSL rose to above its present level in the middle Holocene.

  8. The effects of nonylphenol and octylphenol on embryonic development of sea urchin (Paracentrotus lividus).

    PubMed

    Arslan, O Cakal; Parlak, H; Oral, R; Katalay, S

    2007-08-01

    In this study, embryotoxic and genotoxic effects of nonylphenol (NP) and octylphenol (OP), which are the derivates of alkylphenol (APs), were evaluated using the gametes and embryos of the sea urchin Paracentrotus lividus. The sperm and eggs of sea urchins were exposed to increasing concentrations of NP (0.937-18.74 microg/L) and OP (5-160 microg/L) under static conditions. The endpoints were sperm fertilization success, quantitative and morphologic changes in mitotic activity, larval malformations, developmental arrest, and embryonic/larval mortality. A dose-response-related reduction (approximately 20%) was observed in fertilization success and significant increases in the number of larvae with skeleton malformations at the pluteus stage of the contaminated sperms. The spermiotoxic and embryotoxic concentrations were determined as 0.937 microg/L for NP and 4.685 microg/L for OP for this species. The embryotoxicity of NP and OP is concentration dependent, and significant growth reduction at the early life stages and an increase in larval malformations as skeleton deformities at the pluteus stage were observed. Cytogenetic analysis of embryos showed a decreasing curve in mitotic indexes (number of mitosis per embryo) with increasing concentrations of NP and OP. It can be concluded that NP and OP adversely affect the reproduction and embryonic developmental stages of the P. lividus and this is of great ecological importance because of the hazard at the population level. PMID:17587143

  9. Developmental effects of two different copper oxide nanomaterials in sea urchin (Lytechinus pictus) embryos.

    PubMed

    Torres-Duarte, Cristina; Adeleye, Adeyemi S; Pokhrel, Suman; Mädler, Lutz; Keller, Arturo A; Cherr, Gary N

    2016-08-01

    Copper oxide nanomaterials (nano-CuOs) are widely used and can be inadvertently introduced into estuarine and marine environments. We analyzed the effects of different nano-CuOs (a synthesized and a less-pure commercial form), as well as ionic copper (CuSO4) on embryo development in the white sea urchin, a well-known marine model. After 96 h of development with both nano-CuO exposures, we did not detect significant oxidative damage to proteins but did detect decreases in total antioxidant capacity. We show that the physicochemical characteristics of the two nano-CuOs play an essential role in their toxicities. Both nano-CuOs were internalized by embryos and their differential dissolution was the most important toxicological parameter. The synthesized nano-CuO showed greater toxicity (EC50 = 450 ppb of copper) and had increased dissolution (2.5% by weight over 96 h) as compared with the less-pure commercial nano-CuO (EC50 = 5395 ppb of copper, 0.73% dissolution by weight over 96 h). Copper caused specific developmental abnormalities in sea urchin embryos including disruption of the aboral-oral axis as a result in changes to the redox environment caused by dissolution of internalized nano-CuO. Abnormal skeleton formation also occurred.

  10. Effects of future sea-level rise on tidal processes on the Patagonian Shelf

    NASA Astrophysics Data System (ADS)

    Carless, Stacey J.; Green, J. A. Mattias; Pelling, Holly E.; Wilmes, Sophie-Berenice

    2016-11-01

    The response of tidally driven processes on the Patagonian Shelf to sea-level rise (SLR) is revisited using large but realistic levels of change in a numerical tidal model. The results relate to previous studies through significant differences in the impact, depending on how SLR is implemented. This is true for how the boundary at the coastline is treated, i.e., if we allow for inundation of land or assume flood defences along the coast, but also for how the sea-level change itself is implemented. Simulations with uniform SLR provide a different, and slightly larger, response than do runs where SLR is based on observed trends. In all cases, the effect on the tidal amplitudes is patchy, with alternating increases and decreases in amplitude along the shelf. Furthermore, simulations with a realistic future change in vertical stratification, thus affecting tidal conversion rates, imply that there may be a small but significant decrease in the amplitudes along the coast. Associated processes, e.g., the location of mixing fronts and potential impacts on biogeochemical cycles on the shelf are also discussed.

  11. Effects of pressure on the dynamics of an oligomeric protein from deep-sea hyperthermophile.

    PubMed

    Shrestha, Utsab R; Bhowmik, Debsindhu; Copley, John R D; Tyagi, Madhusudan; Leão, Juscelino B; Chu, Xiang-qiang

    2015-11-10

    Inorganic pyrophosphatase (IPPase) from Thermococcus thioreducens is a large oligomeric protein derived from a hyperthermophilic microorganism that is found near hydrothermal vents deep under the sea, where the pressure is up to 100 MPa (1 kbar). It has attracted great interest in biophysical research because of its high activity under extreme conditions in the seabed. In this study, we use the quasielastic neutron scattering (QENS) technique to investigate the effects of pressure on the conformational flexibility and relaxation dynamics of IPPase over a wide temperature range. The β-relaxation dynamics of proteins was studied in the time ranges from 2 to 25 ps, and from 100 ps to 2 ns, using two spectrometers. Our results indicate that, under a pressure of 100 MPa, close to that of the native environment deep under the sea, IPPase displays much faster relaxation dynamics than a mesophilic model protein, hen egg white lysozyme (HEWL), at all measured temperatures, opposite to what we observed previously under ambient pressure. This contradictory observation provides evidence that the protein energy landscape is distorted by high pressure, which is significantly different for hyperthermophilic (IPPase) and mesophilic (HEWL) proteins. We further derive from our observations a schematic denaturation phase diagram together with energy landscapes for the two very different proteins, which can be used as a general picture to understand the dynamical properties of thermophilic proteins under pressure. PMID:26504206

  12. Effects of tectonism, eustatic sea level fluctuations, and climatic changes on Paleogene sedimentation in California

    SciTech Connect

    Nilsen, T.H.

    1988-03-01

    Paleogene sedimentation in California was strongly influenced by syndepositional tectonism, eustatic sea level changes, and variations in climate. Tectonic activity was most important in controlling sedimentation in basins that developed in mobile areas such as the Salinian block, Coast Ranges, Transverse Ranges, southern California borderland, and along the continental slope adjacent to the trench that formed the California plate margin. Although plutonism had largely terminated in California by Paleogene time, continued uplift of the Mesozoic batholithic complexes of the Klamath Mountains, Sierra Nevada, Mojave Desert, and Salinian block yielded abundant plutoniclastic detritus to paleogene basins. Accretion of exotic terranes during the Paleocene and early eocene, major uplift of the Franciscan assemblage in various parts of California during the Eocene, syndepositional faulting in numerous areas, angular unconformities, and coarse clastic sequences that include alluvial-fan and fault-scarp breccias are features that indicate major tectonic control of sedimentation in Paleogene basins. Renewed volcanism, starting during the late Eocene in northern California in the ancestral Cascade volcanic arc, and in the late Oligocene in many other parts of California, began to supply abundant volcaniclastic sediments locally. In some relatively stable areas, such as the flanks of the Peninsular Ranges and parts of the San Joaquin and Sacramento basins, the effects of global sea level changes on the sedimentary record are easily discerned. Climatic cycles had significant control over Paleogene sedimentation in some of these stable areas.

  13. Investigation on tsunami effects in the central Adriatic Sea during the last century - a contribution

    NASA Astrophysics Data System (ADS)

    Maramai, A.; Graziani, L.; Tinti, S.

    2007-01-01

    In this work we present the result of a study aimed at examining the Italian earthquake sequences that occurred in the area of the central Adriatic sea with the purpose of understanding whether some of them were accompanied by tsunami effects. The motivation for this research was the update and enrichment of the Italian Tsunami Catalogue. The result was that evidence was found for two new cases of earthquake-induced tsunamis: these are the August 1916 Rimini and the October 1930 Ancona events. The bulk of the present research consisted in collecting all the available data on the earthquakes that affected the selected area in the past century and in identifying those potentially capable of generating tsunamis. During the study all the available material was gathered, which includes specific monographs and scientific papers, articles available in contemporary chronicles and in local and national newspapers. The final result of this research will improve our knowledge of the tsunamigenic activity of the central Adriatic sea and contribute to the assessment of the tsunami hazard and risk along these coasts, that especially in the peak season form one of the most densely populated areas of the Italian peninsula with flat and large beaches and water front resorts crowded of tourists.

  14. Effect of dietary herbal supplements on some physiological conditions of Sea Bass Dicentrarchus labrax.

    PubMed

    Yilmaz, Sevdan; Ergun, Sebahattin; Celik, Ekrem Sanver

    2013-06-01

    This study was conducted in order to investigate the effects of dietary thyme Thymus vulgaris, rosemary Rosmarinus officinalis,and fenugreek Trigonella foenum graecum as feed additives on total liver fat levels and biometric indices of Sea Bass Dicentrarchus labrax. Four isonitrogenous (48% crude protein) and isocaloric(21 kJ/g) diets were formulated to contain 0% (control), or 1% of thyme, rosemary, or fenugreek. In a 45-d feeding trial, 12 fiberglass tanks (140 L) were each stocked with 17 fish (20.43 ± 0.03 g).Herbal supplemented diets significantly decreased the total liver fat, visceral fat index, viscerosomatic index, hepatosomatic index,and increased the spleen–somatic index and bile–somatic index(P<0.05). In conclusion, the results indicated that a dietary level of1.0% for thyme, rosemary, or fenugreek could improve some of the physiological parameters of Sea Bass. Thus, this work provides anew perspective for the use of medicinal herbs that can be added to fish feed to improve the status of fish organs. Thyme, rosemary, and fenugreek contain a number of different active components, which possibly play an important role in improving these conditions, but the mechanism by which this is achieved needs further and more detailed study. PMID:23914399

  15. Effect of beam hardening on a visibility-contrast image obtained by X-ray grating interferometry.

    PubMed

    Yashiro, Wataru; Vagovič, Patrik; Momose, Atsushi

    2015-09-01

    X-ray grating interferometry has been highlighted in the last decade as a multi-modal X-ray phase-imaging technique for providing absorption, differential phase, and visibility-contrast images. It has been mainly reported that the visibility contrast in the visibility-contrast image originates from unresolvable random microstructures. In this paper, we show that the visibility contrast is even reduced by a uniform sample with flat surfaces due to the so-called "beam-hardening effect", which has to be taken into account when X-rays with a continuous spectrum is used. We drive a criterion for determining whether the beam-hardening effect occurs or not, and propose a method for correcting the effect of beam hardening on a visibility-contrast image.

  16. Effect of hydrogenation on the memory properties of Si nanocrystals obtained by inductively coupled plasma chemical vapor deposition

    NASA Astrophysics Data System (ADS)

    Cha, Young-Kwan; Park, Sangjin; Park, Youngsoo; Yoo, In-Kyeong; Cha, Daigil; Shin, Jung H.; Choi, Suk-Ho

    2006-11-01

    Effect of hydrogenation on memory properties has been studied for metal-oxide-semiconductor (MOS) structures with Si nanocrystals fabricated using inductively coupled plasma chemical vapor deposition and subsequent annealing. Hydrogenation induces a drastic increase of a dip in the quasistatic capacitance-voltage (C-V) curve of the MOS capacitor, caused by the reduction of the interface states due to hydrogen passivation. This is consistent with high-frequency C-V measurements showing more well-defined curves with less distortion in hydrogenated samples. After hydrogenation, the MOS device shows a significantly larger decrease of flatband voltage shift in electron charging than in hole charging, indicating more effective passivation of the defect states related to the electron charging. A longer retention time is found for electron charging after hydrogenation, but almost no change of charge loss rate for hole charging. These results suggest that an asymmetry exists in the effect of hydrogenation between electron and hole storage.

  17. Effects of carbofuran on the sea bass (Dicentrarchus labrax L.): study of biomarkers and behaviour alterations.

    PubMed

    Hernández-Moreno, David; Pérez-López, Marcos; Soler, Francisco; Gravato, Carlos; Guilhermino, Lúcia

    2011-10-01

    The objective of this study was to investigate the acute effects of the pesticide carbofuran on the sea bass (Dicentrarchus labrax) using parameters at different levels of biological organisation (swimming behaviour and several biomarkers) and possible relationships between alterations found in different effect criteria. In a bioassay, sea bass juveniles were individually exposed to different doses of carbofuran (31, 63, 125 and 250 μg/L) for 96 h. At the end of the bioassay, the swimming performance and 11 biomarkers were determined. Biomarkers were: hepatosomatic index (HSI), lipid peroxidation (LPO), reduced glutathione and the activities of the enzymes ethoxyresorufin O-deethylase (EROD), glutathione S-transferases, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, brain acetylcholinesterase (AChE) and muscle cholinesterases (ChE). After 96 h of exposure, carbofuran induced a decrease of the swimming velocity and inhibition of EROD activity at all concentrations tested, and inhibition of muscle ChE and brain AChE activities at 250 μg/L. No relevant alterations in any of the other tested parameters were found. These results show that carbofuran induced adverse effects on fish by interfering with neurofunction, capability of detoxication and swimming velocity. In addition, positive and significant correlations between the swimming velocity and (i) brain AChE activity, (ii) muscle ChE activity and (iii) EROD activity suggest that the inhibition of these enzymes may somehow be related to the behavioural changes observed. Since these functions are determinant for the survival and performance of the fish in the wild, the findings of the present study suggest that adverse effects may occur in populations exposed to carbofuran if a sufficient number of animals is affected.

  18. Dive, food, and exercise effects on blood microparticles in Steller sea lions (Eumetopias jubatus): exploring a biomarker for decompression sickness.

    PubMed

    Fahlman, Andreas; Moore, Michael J; Trites, Andrew W; Rosen, David A S; Haulena, Martin; Waller, Nigel; Neale, Troy; Yang, Ming; Thom, Stephen R

    2016-04-01

    Recent studies of stranded marine mammals indicate that exposure to underwater military sonar may induce pathophysiological responses consistent with decompression sickness (DCS). However, DCS has been difficult to diagnose in marine mammals. We investigated whether blood microparticles (MPs, measured as number/μl plasma), which increase in response to decompression stress in terrestrial mammals, are a suitable biomarker for DCS in marine mammals. We obtained blood samples from trained Steller sea lions (Eumetopias jubatus, 4 adult females) wearing time-depth recorders that dove to predetermined depths (either 5 or 50 meters). We hypothesized that MPs would be positively related to decompression stress (depth and duration underwater). We also tested the effect of feeding and exercise in isolation on MPs using the same blood sampling protocol. We found that feeding and exercise had no effect on blood MP levels, but that diving caused MPs to increase. However, blood MP levels did not correlate with diving depth, relative time underwater, and presumed decompression stress, possibly indicating acclimation following repeated exposure to depth. PMID:26843583

  19. Dive, food, and exercise effects on blood microparticles in Steller sea lions (Eumetopias jubatus): exploring a biomarker for decompression sickness.

    PubMed

    Fahlman, Andreas; Moore, Michael J; Trites, Andrew W; Rosen, David A S; Haulena, Martin; Waller, Nigel; Neale, Troy; Yang, Ming; Thom, Stephen R

    2016-04-01

    Recent studies of stranded marine mammals indicate that exposure to underwater military sonar may induce pathophysiological responses consistent with decompression sickness (DCS). However, DCS has been difficult to diagnose in marine mammals. We investigated whether blood microparticles (MPs, measured as number/μl plasma), which increase in response to decompression stress in terrestrial mammals, are a suitable biomarker for DCS in marine mammals. We obtained blood samples from trained Steller sea lions (Eumetopias jubatus, 4 adult females) wearing time-depth recorders that dove to predetermined depths (either 5 or 50 meters). We hypothesized that MPs would be positively related to decompression stress (depth and duration underwater). We also tested the effect of feeding and exercise in isolation on MPs using the same blood sampling protocol. We found that feeding and exercise had no effect on blood MP levels, but that diving caused MPs to increase. However, blood MP levels did not correlate with diving depth, relative time underwater, and presumed decompression stress, possibly indicating acclimation following repeated exposure to depth.

  20. Direct radiative effects of sea salt for the Mediterranean region under conditions of low to moderate wind speeds

    NASA Astrophysics Data System (ADS)

    Lundgren, K.; Vogel, B.; Vogel, H.; Kottmeier, Ch.

    2013-02-01

    ABSTRACT This study deals with the direct radiative effect of sea salt on the regional scale, within both the shortwave and longwave ranges. The COSMO-ART model system has been extended and applied for a large part of Europe and adjacent waters within this investigation. For the radiation calculations, we determined the sea salt optical properties based on Mie calculations, giving the optical properties for the three sea salt modes and eight spectral intervals. The simulated sea salt aerosol optical depth is found to show strong dependence on the 10 m wind speed under cloud-free conditions. This relation is best represented by a power law fit and compares well with satellite observations. For clear-sky conditions, the simulated sea salt direct radiative effects on the shortwave and longwave radiative budgets are approximately of the same order of magnitude, but with opposite signs. This causes the net radiative effect to approach zero, which leads to a low impact on the temperature for this area.

  1. Antinociceptive Effect of the Essential Oil Obtained from the Leaves of Croton cordiifolius Baill. (Euphorbiaceae) in Mice.

    PubMed

    Nogueira, Lenise de Morais; da Silva, Monalisa Ribeiro; Dos Santos, Simone Maria; de Albuquerque, Julianna Ferreira Cavalcanti; Ferraz, Igor Cavalcanti; de Albuquerque, Thaíse Torres; Mota, Carlos Renato França de Carvalho; Araújo, Renata Mendonça; Viana, Glauce Socorro de Barros; Martins, René Duarte; Havt, Alexandre; Ximenes, Rafael Matos

    2015-01-01

    Croton cordiifolius Baill. is a shrub known as "quebra-faca" and is used to treat inflammation, pain, wounds, and gastrointestinal disturbances in the semiarid region in the northeast of Brazil. In an ethnobotanical survey in the state of Pernambuco, "quebra-faca" use was cited in 33% of the interviews. Thus, we decided to evaluate the antinociceptive effects of the essential oil from C. cordiifolius (CcEO). Chemical analysis by gas chromatography-mass spectrometry revealed 1,8-cineole (25.09%) and α-phellandrene (15.43%) as major constituents. Antinociceptive activity was evaluated using murine models of chemically induced pain (writhing induced by acetic acid, formalin, capsaicin, and glutamate tests). Opioid and central nervous systems (CNS) involvement were also investigated. Regarding antinociceptive activity, CcEO (50 and 100 mg/kg) reduced the number of writhing responses induced by acetic acid and decreased the licking times in both phases of the formalin test. CcEO also was evaluated in capsaicin- and glutamate-induced nociception. While no effect was observed in the capsaicin test, CcEO (100 mg/kg) was effective in the glutamate test. Naloxone, an opioid antagonist, did not affect the antinociceptive activity of CcEO in writhing test. In conclusion, the antinociceptive effect of CcEO could be explained, at least in part, by inhibition of the glutamatergic system. PMID:25821494

  2. Role of Visual Familiarity in the Word-Superiority Effects Obtained with the Simultaneous-Matching Task

    ERIC Educational Resources Information Center

    Bruder, Gail A.

    1978-01-01

    Three experiments assessed the effect of visual familiarity of words on "same-different" reaction times (RTs) in a simultaneous-matching task. All three studies showed visual familiarity to be responsible for differences in slope over sequence length between words and nonwords. (Editor/RK)

  3. Antinociceptive Effect of the Essential Oil Obtained from the Leaves of Croton cordiifolius Baill. (Euphorbiaceae) in Mice

    PubMed Central

    Nogueira, Lenise de Morais; da Silva, Monalisa Ribeiro; dos Santos, Simone Maria; de Albuquerque, Julianna Ferreira Cavalcanti; Ferraz, Igor Cavalcanti; de Albuquerque, Thaíse Torres; Mota, Carlos Renato França de Carvalho; Araújo, Renata Mendonça; Viana, Glauce Socorro de Barros; Martins, René Duarte; Ximenes, Rafael Matos

    2015-01-01

    Croton cordiifolius Baill. is a shrub known as “quebra-faca” and is used to treat inflammation, pain, wounds, and gastrointestinal disturbances in the semiarid region in the northeast of Brazil. In an ethnobotanical survey in the state of Pernambuco, “quebra-faca” use was cited in 33% of the interviews. Thus, we decided to evaluate the antinociceptive effects of the essential oil from C. cordiifolius (CcEO). Chemical analysis by gas chromatography-mass spectrometry revealed 1,8-cineole (25.09%) and α-phellandrene (15.43%) as major constituents. Antinociceptive activity was evaluated using murine models of chemically induced pain (writhing induced by acetic acid, formalin, capsaicin, and glutamate tests). Opioid and central nervous systems (CNS) involvement were also investigated. Regarding antinociceptive activity, CcEO (50 and 100 mg/kg) reduced the number of writhing responses induced by acetic acid and decreased the licking times in both phases of the formalin test. CcEO also was evaluated in capsaicin- and glutamate-induced nociception. While no effect was observed in the capsaicin test, CcEO (100 mg/kg) was effective in the glutamate test. Naloxone, an opioid antagonist, did not affect the antinociceptive activity of CcEO in writhing test. In conclusion, the antinociceptive effect of CcEO could be explained, at least in part, by inhibition of the glutamatergic system. PMID:25821494

  4. Melatonin ameliorates dexamethasone-induced inhibitory effects on the proliferation of cultured progenitor cells obtained from adult rat hippocampus.

    PubMed

    Ekthuwapranee, Kasima; Sotthibundhu, Areechun; Tocharus, Chainarong; Govitrapong, Piyarat

    2015-01-01

    Glucocorticoids, hormones that are released in response to stress, induce neuronal cell damage. The hippocampus is a primary target of glucocorticoids in the brain, the effects of which include the suppression of cell proliferation and diminished neurogenesis in the dentate gyrus. Our previous study found that melatonin, synthesized primarily in the pineal, pretreatment prevented the negative effects of dexamethasone, the glucocorticoid receptor agonist, on behavior and neurogenesis in rat hippocampus. In the present study, we attempted to investigate the interrelationship between melatonin and dexamethasone on the underlying mechanism of neural stem cell proliferation. Addition of dexamethasone to hippocampal progenitor cells from eight-week old rats resulted in a decrease in the number of neurospheres; pretreatment with melatonin precluded these effects. The immunocytochemical analyses indicated a reduction of Ki67 and nestin-positive cells in the dexamethasone-treated group, which was minimized by melatonin pretreatment. A reduction of the extracellular signal-regulated kinase 1 and 2 (ERK1/2) phosphorylation and G1-S phase cell cycle regulators cyclin E and CDK2 in dexamethasone-treated progenitor cells were prevented by pretreatment of melatonin. Moreover, luzindole, a melatonin receptor antagonist blocked the positive effect of melatonin whereas RU48, the glucocorticoid receptor antagonist blocked the negative effect of dexamethasone on the number of neurospheres. Moreover, we also found that dexamethasone increased the glucocorticoid receptor protein but decreased the level of MT1 melatonin receptor, whereas melatonin increased the level of MT1 melatonin receptor but decreased the glucocorticoid receptor protein. These suggest the crosstalk and cross regulation between the melatonin receptor and the glucocorticoid receptor on hippocampal progenitor cell proliferation.

  5. Assignment of Calibration Information to Deeper Phylogenetic Nodes is More Effective in Obtaining Precise and Accurate Divergence Time Estimates.

    PubMed

    Mello, Beatriz; Schrago, Carlos G

    2014-01-01

    Divergence time estimation has become an essential tool for understanding macroevolutionary events. Molecular dating aims to obtain reliable inferences, which, within a statistical framework, means jointly increasing the accuracy and precision of estimates. Bayesian dating methods exhibit the propriety of a linear relationship between uncertainty and estimated divergence dates. This relationship occurs even if the number of sites approaches infinity and places a limit on the maximum precision of node ages. However, how the placement of calibration information may affect the precision of divergence time estimates remains an open question. In this study, relying on simulated and empirical data, we investigated how the location of calibration within a phylogeny affects the accuracy and precision of time estimates. We found that calibration priors set at median and deep phylogenetic nodes were associated with higher precision values compared to analyses involving calibration at the shallowest node. The results were independent of the tree symmetry. An empirical mammalian dataset produced results that were consistent with those generated by the simulated sequences. Assigning time information to the deeper nodes of a tree is crucial to guarantee the accuracy and precision of divergence times. This finding highlights the importance of the appropriate choice of outgroups in molecular dating. PMID:24855333

  6. Native and structurally modified gum arabic: exploring the effect of the gum's microstructure in obtaining electroactive nanoparticles.

    PubMed

    Cornelsen, Patricia A; Quintanilha, Ronaldo C; Vidotti, Marcio; Gorin, Philip A J; Simas-Tosin, Fernanda F; Riegel-Vidotti, Izabel C

    2015-03-30

    Electroactive nanoparticles combining gum arabic (GA) and polyaniline (PANI) were prepared by chemical synthesis. The gum consists of highly branched anionic polysaccharides with some protein content. GA was structurally modified by Smith controlled degradation, in order to reduce its degree of branching (GAD), aiming the elucidation of the relationship between the structure and the properties of complex polysaccharides. The modification was studied by SEC, GC-MS, (13)C NMR and colorimetric methods. GAD has lower molecular mass, lower degree of branching and lower uronic acid content. Besides it is enriched in galactose and protein when compared with GA. The obtained composites (GA-PANI and GAD-PANI) were thoroughly characterized. Although the use of both polysaccharides (GA and GAD) produced highly stable electroactive nanoparticles, the best combination of properties was achieved for GA-PANI. The sample GAD was not able to prevent the occurrence of crosslinking between PANI chains, possibly due to its lower microstructural complexity which diminishes the occurrence of hydrogen bonds between the polymers. PMID:25563942

  7. A study on annealing effects of AgInS2/GaAs epilayer obtained from photoluminescence measurements

    NASA Astrophysics Data System (ADS)

    Hong, K. J.; Jeong, J. W.; Baek, H. W.; Kim, K. S.; Moon, J. D.; Kim, H. S.; Im, K. H.

    2002-05-01

    The AgInS2 epilayers with a chalcopyrite structure grown using a hot-wall epitaxy (HWE) method have been confirmed to be a high quality crystal. From the optical absorption measurement, the temperature dependence of the energy band gap on AgInS2/GaAs was found to be Eg(T)=2.1365 eV-(9.89×10-3 eV)T2/(2930+T). After the as-grown AgInS2/GaAs was annealed in Ag-, S-, and In-atmospheres, the origin of point defects of AgInS2/GaAs has been investigated by using the photoluminescence (PL) at 10 K. The native defects of VAg, VS, Agint, and Sint obtained from PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the S-atmosphere converted AgInS2/GaAs to an optical p-type. Also, we confirmed that In in AgInS2/GaAs did not form the native defects because In in AgInS2 did exist in the form of stable bonds.

  8. Effect of organic acid pretreatment on some physical, functional and antioxidant properties of flour obtained from three unripe banana cultivars.

    PubMed

    Anyasi, Tonna A; Jideani, Afam I O; Mchau, Godwin R A

    2015-04-01

    Unripe banana flour (UBF) obtained from organic acid pretreatment of pulp from three non-commercial cultivars were profiled for physical, functional and antioxidant properties. UBF showed marked significant differences (p<0.05) in colour (CIEL(∗)a(∗)b(∗) and CIELCH) and water holding capacity with no significant difference in oil holding capacity. The total polyphenol content (TPC) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) differed significantly with M-red UBF recording high TPC (1130.39 ± 27.26 mg GAE/100g d.w.) at 10 g/L citric acid pretreatment. Correlation analysis between TPC and DPPH showed very strong positive correlation for Mabonde UBF in citric and lactic acid pretreatment (r = 0.999, p < 0.01; r = 0.985, p < 0.01), while inverse correlation was recorded in M-red UBF for ascorbic and lactic acid pretreatment (r = -0.031; r = -0.137). Organic acid pretreatment enhances the physical and antioxidant properties of UBF hitherto absent in composite food formulations.

  9. Sea-level line extraction based on piecewise line detection

    NASA Astrophysics Data System (ADS)

    Lei, Bo; Ren, Tingting; Liu, Yingbin; Yu, Jianwei

    2014-11-01

    In infrared image, sea-level line could be hard to distinguish because of noises caused by wave clutters and sunlight conditions.This paper proposed a fast sea-level line extraction method which could localize the sea-level line in complex infrared sea-sky scenes. First, a down sample operation was performed to obtain a low resolution image which could reduce the time consumption without blurring the sea-level line, and then the Canny edge detection was carried out to extract edges in the scene. Second, the intersecting edges were separated by removing the joints of edges according to a certain rule, and the bounding rectangle of every short edge was obtained which helped to select straight lines, and then a long edge segmentation operation was used to count in possible sea-level line. Third, a line concatenation method was performed by their slopes and intercepts comparison. Finally, for sea-level line verification, the second-order vertical grads are calculated in the two sides of possible sea-level line. Experiments show that the proposed method is fast and effective for various kinds of infrared sea-sky scenes, and it is feasible even for the scenes where the sea-level line is blurring and hard to distinguish.

  10. Utility of deep sea CO2 release experiments in understanding the biology of a high-CO2 ocean: Effects of hypercapnia on deep sea meiofauna

    NASA Astrophysics Data System (ADS)

    Barry, James P.; Buck, Kurt R.; Lovera, Chris; Kuhnz, Linda; Whaling, Patrick J.

    2005-09-01

    Oceanic CO2 levels are expected to rise during the next 2 centuries to levels not seen for 10-150 million years by the uptake of atmospheric CO2 in surface waters or potentially through the disposal of waste CO2 in the deep sea. Changes in ocean chemistry caused by CO2 influx may have broad impacts on ocean ecosystems. Physiological processes animals use to cope with CO2-related stress are known, but the range of sensitivities and effects of changes in ocean chemistry on most ocean life remain unclear. We evaluate the effectiveness of various designs for in situ CO2 release experiments in producing stable perturbations in seawater chemistry over experimental seafloor plots, as is desirable for evaluating the CO2 sensitivities of deep sea animals. We also discuss results from a subset of these experiments on the impacts of hypercapnia on deep sea meiofauna, in the context of experimental designs. Five experiments off central California show that pH perturbations were greatest for experiments using "point source" CO2 pools surrounded by experimental plots. CO2 enclosure experiments with experimental plots positioned within a circular arrangement of CO2 pools had more moderate pH variation. The concentration of dissolution plumes from CO2 pools were related to the speed and turbulence of near-bottom currents, which influence CO2 dissolution and advection. Survival of meiofauna (nematodes, amoebae, euglenoid flagellates) was low after episodic severe hypercapnia but lower and variable where pH changes ranged from 0 to 0.2 pH units below normal.

  11. Limacina retroversa's response to combined effects of ocean acidification and sea water freshening

    NASA Astrophysics Data System (ADS)

    Manno, C.; Morata, N.; Primicerio, R.

    2012-11-01

    Anthropogenic carbon dioxide emissions induce ocean acidification, thereby reducing carbonate ion concentration, which may affect the ability of calcifying organisms to build shells. Pteropods, the main planktonic producers of aragonite in the worlds' oceans, may be particularly vulnerable to changes in sea water chemistry. The negative effects are expected to be most severe at high-latitudes, where natural carbonate ion concentrations are low. In this study we investigated the combined effects of ocean acidification and freshening on Limacina retroversa, the dominant pteropod in sub polar areas. Living L. retroversa, collected in Northern Norwegian Sea, were exposed to four different pH values ranging from the pre-industrial level to the forecasted end of century ocean acidification scenario. Since over the past half-century the Norwegian Sea has experienced a progressive freshening with time, each pH level was combined with a salinity gradient in two factorial, randomized experiments investigating shell degradation, swimming behavior and survival. In addition, to investigate shell degradation without any physiologic influence, one perturbation experiments using only shells of dead pteropods was performed. Lower pH reduced shell mass whereas shell dissolution increased with pCO2. Interestingly, shells of dead organisms had a higher degree of dissolution than shells of living individuals. Mortality of Limacina retroversa was strongly affected only when both pH and salinity reduced simultaneously. The combined effects of lower salinity and lower pH also affected negatively the ability of pteropods to swim upwards. Results suggest that the energy cost of maintaining ion balance and avoiding sinking (in low salinity scenario) combined with the extra energy cost necessary to counteract shell dissolution (in high pCO2 scenario), exceed the available energy budget of this organism causing the pteropods to change swimming behavior and begin to collapse. Since L

  12. Comparative essential oil composition and antifungal effect of bitter fennel (Foeniculum vulgare ssp. piperitum) fruit oils obtained during different vegetation.

    PubMed

    Ozcan, Mehmet Musa; Chalchat, Jean-Claude; Arslan, Derya; Ateş, Ayşe; Unver, Ahmet

    2006-01-01

    The chemical composition of the flower and unripe and ripe fruits from fennel (bitter) (Foeniculum vulgare ssp. piperitum) has been examined by gas chromatography and gas chromatography-mass spectrometry. The main identified components of the flower and unripe and ripe fruit oils were estragole (53.08%, 56.11%, and 61.08%), fenchone (13.53%, 19.18%, and 23.46%), and alpha-phellandrene (5.77%, 3.30%, and 0.72%), respectively. Minor qualitative and major quantitative variations for some compounds of essential oils were determined with respect to the different parts of F. vulgare. The oils exerted varying levels of antifungal effects on the experimental mycelial growth of Alternaria alternata, Fusarium oxysporum, and Rhizoctonia solani. The 40 ppm concentrations of fennel oils showed inhibitory effect against mycelial growth of A. alternaria, whereas 10 ppm levels were ineffective. The analyses show that fennel oils exhibited different degrees of fungistatic activity depending on the doses.

  13. Assessing pollution-related effects of oil spills from ships in the Chinese Bohai Sea.

    PubMed

    Liu, Xin; Guo, Mingxian; Wang, Yebao; Yu, Xiang; Guo, Jie; Tang, Cheng; Hu, Xiaoke; Wang, Chuanyuan; Li, Baoquan

    2016-09-15

    An analysis of the effects of potential oil spills will provide data in support of decisions related to improving the response to oil spills and its emergency management. We selected the Chinese Bohai Sea, especially the Bohai Strait, as our investigation region to provide an assessment of the effects of pollution from ship-related oil spills on adjacent coastal zones. Ship-related accidents are one of the major factors causing potential oil spills in this area. A three dimensional oil transport and transformation model was developed using the Estuary, Coastal, and Ocean Model. This proposed model was run 90 times and each run lasted for 15days to simulate the spread and weathering processes of oil for each of four potential spill sites, which represented potential sites of ship collisions along heavy traffic lanes in the Bohai Sea. Ten neighboring coastal areas were also considered as target zones that potentially could receive pollutants once oil spilled in the study areas. The statistical simulations showed that spills in winter were much worse than those in summer; they resulted in very negative effects on several specific target zones coded Z7, Z8, Z9, and Z10 in this paper. In addition, sites S3 (near the Penglai city) and S4 (near the Yantai city) were the two most at-risk sites with a significantly high probability of pollution if spills occurred nearby during winter. The results thus provided practical guidelines for local oil spill prevention, as well as an emergency preparedness and response program.

  14. Effect of primary organic sea spray emissions on cloud condensation nuclei concentrations

    NASA Astrophysics Data System (ADS)

    Westervelt, D. M.; Moore, R. H.; Nenes, A.; Adams, P. J.

    2011-02-01

    This work quantifies the primary marine organic aerosol global emission source and its impact on cloud condensation nuclei (CCN) concentrations by implementing an organic sea spray source function into a series of global aerosol simulations. The source function assumes that a fraction of the sea spray emissions, depending on the local chlorophyll concentration, is organic matter in place of NaCl. Effect on CCN concentrations (at 0.2% supersaturation) is modeled using the Two-Moment Aerosol Sectional (TOMAS) microphysics algorithm coupled to the GISS II-prime general circulation model. The presence of organics affects CCN activity in competing ways: by reducing the amount of solute available in the particle and decreasing surface tension of CCN. To model surfactant effects, surface tension depression data from seawater samples taken near the Georgia coast were applied as a function of carbon concentrations. A global marine organic aerosol emission rate of 17.7 Tg C yr-1 is estimated from the simulations. Marine organics exert a localized influence on CCN(0.2%) concentrations, decreasing regional concentrations by no more than 5% and by less than 0.5% over most of the globe. The decrease in CCN concentrations results from the fact that the decrease in particle solute concentration outweighs the organic surfactant effects. The low sensitivity of CCN(0.2%) to the marine organic emissions is likely due to the small compositional changes: the mass fraction of OA in accumulation mode aerosol increases by only 15% in a biologically active region of the Southern Ocean.

  15. Physiological effects of environmental acidification in the deep-sea urchin Strongylocentrotus fragilis

    NASA Astrophysics Data System (ADS)

    Taylor, J. R.; Lovera, C.; Whaling, P. J.; Buck, K. R.; Pane, E. F.; Barry, J. P.

    2014-03-01

    Anthropogenic CO2 is now reaching depths over 1000 m in the Eastern Pacific, overlapping the Oxygen Minimum Zone (OMZ). Deep-sea animals are suspected to be especially sensitive to environmental acidification associated with global climate change. We have investigated the effects of elevated pCO2 and variable O2 on the deep-sea urchin Strongylocentrotus fragilis, a species whose range of 200-1200 m depth includes the OMZ and spans a pCO2 range of approx. 600-1200 μatm (approx. pH 7.6 to 7.8). Individuals were evaluated during two exposure experiments (1-month and 4 month) at control and three levels of elevated pCO2 at in situ O2 levels of approx. 10% air saturation. A treatment of control pCO2 at 100% air saturation was also included in experiment two. During the first experiment, perivisceral coelomic fluid (PCF) acid-base balance was investigated during a one-month exposure; results show S. fragilis has limited ability to compensate for the respiratory acidosis brought on by elevated pCO2, due in part to low non-bicarbonate PCF buffering capacity. During the second experiment, individuals were separated into fed and fasted experimental groups, and longer-term effects of elevated pCO2 and variable O2 on righting time, feeding, growth, and gonadosomatic index (GSI) were investigated for both groups. Results suggest that the acidosis found during experiment one does not directly correlate with adverse effects during exposure to realistic future pCO2 levels.

  16. Assessing pollution-related effects of oil spills from ships in the Chinese Bohai Sea.

    PubMed

    Liu, Xin; Guo, Mingxian; Wang, Yebao; Yu, Xiang; Guo, Jie; Tang, Cheng; Hu, Xiaoke; Wang, Chuanyuan; Li, Baoquan

    2016-09-15

    An analysis of the effects of potential oil spills will provide data in support of decisions related to improving the response to oil spills and its emergency management. We selected the Chinese Bohai Sea, especially the Bohai Strait, as our investigation region to provide an assessment of the effects of pollution from ship-related oil spills on adjacent coastal zones. Ship-related accidents are one of the major factors causing potential oil spills in this area. A three dimensional oil transport and transformation model was developed using the Estuary, Coastal, and Ocean Model. This proposed model was run 90 times and each run lasted for 15days to simulate the spread and weathering processes of oil for each of four potential spill sites, which represented potential sites of ship collisions along heavy traffic lanes in the Bohai Sea. Ten neighboring coastal areas were also considered as target zones that potentially could receive pollutants once oil spilled in the study areas. The statistical simulations showed that spills in winter were much worse than those in summer; they resulted in very negative effects on several specific target zones coded Z7, Z8, Z9, and Z10 in this paper. In addition, sites S3 (near the Penglai city) and S4 (near the Yantai city) were the two most at-risk sites with a significantly high probability of pollution if spills occurred nearby during winter. The results thus provided practical guidelines for local oil spill prevention, as well as an emergency preparedness and response program. PMID:27357917

  17. Effects of agri-environmental schemes on farmland birds: do food availability measurements improve patterns obtained from simple habitat models?

    PubMed

    Ponce, Carlos; Bravo, Carolina; Alonso, Juan Carlos

    2014-07-01

    Studies evaluating agri-environmental schemes (AES) usually focus on responses of single species or functional groups. Analyses are generally based on simple habitat measurements but ignore food availability and other important factors. This can limit our understanding of the ultimate causes determining the reactions of birds to AES. We investigated these issues in detail and throughout the main seasons of a bird's annual cycle (mating, postfledging and wintering) in a dry cereal farmland in a Special Protection Area for farmland birds in central Spain. First, we modeled four bird response parameters (abundance, species richness, diversity and "Species of European Conservation Concern" [SPEC]-score), using detailed food availability and vegetation structure measurements (food models). Second, we fitted new models, built using only substrate composition variables (habitat models). Whereas habitat models revealed that both, fields included and not included in the AES benefited birds, food models went a step further and included seed and arthropod biomass as important predictors, respectively, in winter and during the postfledging season. The validation process showed that food models were on average 13% better (up to 20% in some variables) in predicting bird responses. However, the cost of obtaining data for food models was five times higher than for habitat models. This novel approach highlighted the importance of food availability-related causal processes involved in bird responses to AES, which remained undetected when using conventional substrate composition assessment models. Despite their higher costs, measurements of food availability add important details to interpret the reactions of the bird community to AES interventions and thus facilitate evaluating the real efficiency of AES programs.

  18. Effects of agri-environmental schemes on farmland birds: do food availability measurements improve patterns obtained from simple habitat models?

    PubMed Central

    Ponce, Carlos; Bravo, Carolina; Alonso, Juan Carlos

    2014-01-01

    Studies evaluating agri-environmental schemes (AES) usually focus on responses of single species or functional groups. Analyses are generally based on simple habitat measurements but ignore food availability and other important factors. This can limit our understanding of the ultimate causes determining the reactions of birds to AES. We investigated these issues in detail and throughout the main seasons of a bird's annual cycle (mating, postfledging and wintering) in a dry cereal farmland in a Special Protection Area for farmland birds in central Spain. First, we modeled four bird response parameters (abundance, species richness, diversity and “Species of European Conservation Concern” [SPEC]-score), using detailed food availability and vegetation structure measurements (food models). Second, we fitted new models, built using only substrate composition variables (habitat models). Whereas habitat models revealed that both, fields included and not included in the AES benefited birds, food models went a step further and included seed and arthropod biomass as important predictors, respectively, in winter and during the postfledging season. The validation process showed that food models were on average 13% better (up to 20% in some variables) in predicting bird responses. However, the cost of obtaining data for food models was five times higher than for habitat models. This novel approach highlighted the importance of food availability-related causal processes involved in bird responses to AES, which remained undetected when using conventional substrate composition assessment models. Despite their higher costs, measurements of food availability add important details to interpret the reactions of the bird community to AES interventions and thus facilitate evaluating the real efficiency of AES programs. PMID:25165523

  19. Effect of photoperiod on characteristics of semen obtained by electroejaculation in stump-tailed macaques (Macaca arctoides).

    PubMed

    García Granados, Mónica Dafne; Hernández López, Leonor Estela; Córdoba Aguilar, Alejandro; Cerda Molina, Ana Lilia; Pérez-Ramírez, Olivia; Mondragón-Ceballos, Ricardo

    2014-07-01

    Some environmental variables determining seasonal reproduction in mammals are temperature, humidity, food availability, and photoperiod. Among these, photoperiod is considered the main regulator of primates' seasonal reproduction, thus the latitudinal distribution of primate populations is a key factor determining the appearance of seasonal reproduction. The present work presents supporting discrete seasonality in male stump-tailed macaques (Macaca arctoides). We investigated whether semen quality and testosterone covaried with Mexico City's photoperiod and relative humidity by analyzing variations in the portions that form the ejaculate: the seminal liquid, the seminal coagulum, and the copulatory plug. Five male adult stump-tailed macaques were electroejaculated once a month, obtaining three semen samples per male, from August 2011 to July 2012 (except for December 2011) (n = 165). Our results showed that stump-tailed macaque sperm counts were significantly different between the portions of the ejaculate. The seminal coagulum contained the significantly largest number of spermatozoids, followed by the copulatory plug and the seminal fluid. Photoperiod and relative humidity had major influence on the sperm count in the seminal coagulum and the testosterone concentrations. Testosterone reached its highest values around the time when days and nights lasted the same hours, decreasing when days either grew longer or became shorter. Concerning relative humidity, sperm counts in the seminal coagulum were highly variable on dry days, but decreased as the relative humidity increased. We conclude that stump-tailed macaques have a discrete seasonality, occurring in spring and fall when macaques' reproductive condition and readiness for postcopulatory intrasexual competition increase. PMID:24585247

  20. Effects of agri-environmental schemes on farmland birds: do food availability measurements improve patterns obtained from simple habitat models?

    PubMed

    Ponce, Carlos; Bravo, Carolina; Alonso, Juan Carlos

    2014-07-01

    Studies evaluating agri-environmental schemes (AES) usually focus on responses of single species or functional groups. Analyses are generally based on simple habitat measurements but ignore food availability and other important factors. This can limit our understanding of the ultimate causes determining the reactions of birds to AES. We investigated these issues in detail and throughout the main seasons of a bird's annual cycle (mating, postfledging and wintering) in a dry cereal farmland in a Special Protection Area for farmland birds in central Spain. First, we modeled four bird response parameters (abundance, species richness, diversity and "Species of European Conservation Concern" [SPEC]-score), using detailed food availability and vegetation structure measurements (food models). Second, we fitted new models, built using only substrate composition variables (habitat models). Whereas habitat models revealed that both, fields included and not included in the AES benefited birds, food models went a step further and included seed and arthropod biomass as important predictors, respectively, in winter and during the postfledging season. The validation process showed that food models were on average 13% better (up to 20% in some variables) in predicting bird responses. However, the cost of obtaining data for food models was five times higher than for habitat models. This novel approach highlighted the importance of food availability-related causal processes involved in bird responses to AES, which remained undetected when using conventional substrate composition assessment models. Despite their higher costs, measurements of food availability add important details to interpret the reactions of the bird community to AES interventions and thus facilitate evaluating the real efficiency of AES programs. PMID:25165523

  1. Effect of Dipolar Cross Correlation on Model-Free Motional Parameters Obtained from 13C Relaxation in AX 2 Systems

    NASA Astrophysics Data System (ADS)

    Zhu, L. Y.; Kemple, M. D.; Landy, S. B.; Buckley, P.

    The importance of dipolar cross correlation in 13C relaxation studies of molecular motion in AX 2 spin systems (A = 13C, X = 1H) was examined. Several different models for the internal motion, including two restricted-diffusion, and two-site jump models, the Kinosita model [K. Kinosita, Jr., S. Kawato, and A. Ikegami, Biophys. J.20, 289 (1977)], and an axially symmetric model, were applied through the Lipari and Szabo [ J. Am. Chem. Soc.104, 4546 (1982)] formalism to calculate errors in 13C T1, obtained from inversion-recovery measurements under proton saturation, and NOE when dipolar cross correlation is neglected. Motional parameters in the Lipari and Szabo formalism, τ m, S2, and τ e, were then determined from T1 and NOE (including the errors) and compared with parameters initially used to simulate the relaxation data. The resulting differences in the motional parameters, while model dependent, were generally small for plausible motions. At larger S2 values (≥ 0.6), the errors in both τ m and S2 were <5%. Errors in τ e increased with S2 but were usually less than 10%. Larger errors in the parameters were found for an axially symmetric model, but with τ m fixed even those were >5% only for the τ m = 1 ns, τ e = 10 ps case. Furthermore, it was observed that deviations in a given motional parameter were mostly of the same sign, which allows bounds to be set on experimentally derived parameters. Relaxation data for the peptide melittin synthesized with gly enriched with 13C at the backbone cu position and with lys enriched with 13C in the side chain were examined in light of the results of the simulations. All in all, it appears that neglect of dipolar cross correlation in 13C T1 (With proton saturation) and NOE measurements in AX 2 systems does not lead to major problems in interpretation of the results in terms of molecular motion.

  2. Effects of multiple freezing (-18 ± 2 °C) and microwave thawing cycles on the quality changes of sea bass (Dicentrarchus labrax).

    PubMed

    Baygar, Taçnur; Alparslan, Yunus

    2015-06-01

    Sensory, chemical [pH, total volatile basic nitrogen (TVB-N), trimethylamine (TMA-N), thiobarbituric acid (TBA)] and composition (crude protein and crude lipid) analyses were carried out on whole, gutted and fillets of seabass that were frozen (-18 ± 2 °C) and thawed more than once in microwave. It was detected that the sensorial acceptability values decreased certainly for all fish samples (whole, gutted and fillets of sea bass) when compared with control group. While chemical (pH, TVB-N, TMA-N, TBA) values increased, crude protein and crude lipid values decreased after the multiple freezing and thawing cycles under microwave. The obtained results offered that thawing by microwave is not appropriate sea bass because of the undesirable cooking effect of microwave to the some parts of fish such as tail, eye and fins. Also skin dryness, moisture losses in eye fluids and textural deteriorations were observed. Significant differences (P < 0.05) were found in general acceptability values and pH, TVB-N, TBA and crude protein results among the sea bass groups thawed in microwave conditions.

  3. Effects of a Range-Expanding Sea Urchin on Behaviour of Commercially Fished Abalone

    PubMed Central

    Strain, Elisabeth M. A.; Johnson, Craig R.; Thomson, Russell J.

    2013-01-01

    Background Global climate change has resulted in a southerly range expansion of the habitat modifying sea urchin Centrostephanus rodgersii to the east coast of Tasmania, Australia. Various studies have suggested that this urchin outcompetes black-lipped abalone (Haliotis rubra) for resources, but experiments elucidating the mechanisms are lacking. Methodology/Principal Findings We outline a new framework involving experimental manipulations and Markov chain and Pareto modelling to examine the effects of interspecific competition between urchins and abalone and the effect of intraspecific competition in abalone, assessed as effects on behaviour. Manipulations of abalone densities had no detectable effect on urchin behavioural transitions, movement patterns or resightability through time. In contrast, additions of urchins resulted in abalone shifting microhabitats from exposed to sheltered positions, an increase in the proportion of mobile abalone, and declines in abalone resightability through time relative to controls without the urchins. Our results support the hypothesis of asymmetrical competitive interactions between urchins and abalone. Conclusions/Significance The introduction of urchins to intact algal beds causes abalone to flee and seek shelter in cryptic microhabitat which will negatively impact both their accessibility to such microhabitats, and productivity of the abalone fishery, and will potentially affect their growth and survival, while the presence of the abalone has no detectable effect on the urchin. Our approach involving field-based experiments and modelling could be used to test the effects of other invasive species on native species behaviour. PMID:24073195

  4. Antihypertensive and antioxidant effects of a hydroalcoholic extract obtained from aerial parts of Otostegia persica (Burm.) Boiss.

    PubMed

    Safaeian, L; Ghasemi-Dehkordi, N; Javanmard, Sh Haghjoo; Namvar, H

    2015-01-01

    Otostegia persica (Burm.) Boiss. is used for the treatment of various diseases in traditional medicine. The aim of this study was to assess the effects of hydroalcoholic extract of the aerial parts of O. persica in dexamethasone (Dex) induced hypertension in male Wistar rats. For induction of hypertension, Dex at 30 μg/kg/day was administered subcutaneously for 14 days. In a prevention study, animals received O. persica extract orally at various doses of 100, 200 and 400 mg/kg 4 days before Dex administration and during the test period lasted for 18 days. In a reversal study, rats received O. persica extract from day 8 to 14. Systolic blood pressure (SBP) was measured using tail-cuff method. The weight of thymus gland was measured as a marker of glucocorticoid activity. The hydrogen peroxide (H2O2) concentration and ferric reducing antioxidant power (FRAP) were determined in plasma samples. Dex injection significantly increased SBP and plasma H2O2 levels while decreased the body and thymus weights and FRAP values. Oral administration of O. persica extract prevented and dose-dependently reversed a rise in SBP. Pre-treatment with O. persica extract also reduced the plasma H2O2 concentration, increased the plasma FRAP levels and prevented the body weight loss upon Dex administration. These results suggest antihypertensive and antioxidant effects of O. persica extract in Dex-induced hypertension. However, further investigations are needed to elucidate the detailed mechanism(s) of antihypertensive effect of this traditional herbal medicine. PMID:26600845

  5. The effect of deformation after backarc spreading between the rear arc and current volcanic front in Shikoku Basin obtained by seismic reflection survey

    NASA Astrophysics Data System (ADS)

    Yamashita, M.; Takahashi, N.; Nakanishi, A.; Kodaira, S.; Tamura, Y.

    2012-12-01

    Detailed crustal structure information of a back-arc basin must be obtained to elucidate the mechanism of its opening. Especially, the Shikoku Basin, which occupies the northern part of the Philippine Sea Plate between the Kyushu-Palau Ridge and the Izu-Bonin (Ogasawara) Arc, is an important area to understand the evolution of the back-arc basins as a part of the growth process of the Philippine Sea. Especially, the crustal structure oft the east side of Shikoku Basin is complicated by colliding to the Izu Peninsula Japan Agency for Marine-Earth Science and Technology has been carried out many multi-channel seismic reflection surveys since 2004 in Izu-Bonin region. Kodaira et al. (2008) reported the results of a refraction seismic survey along a north-south profile within paleoarc in the rear arc (i.e., the Nishi-shichito ridge) about 150 km west of current volcanic front. According to their results, the variation relationship of crustal thickness between the rear arc and volcanic front is suggested the evidence of rifting from current volcanic arc. There is the en-echelon arrangement is located in the eastern side of Shikoku Basin from current arc to rear arc, and it is known to activate after ceased spreading at 15 Ma (Okino et al., 1994) of Shikoku Basin by geologic sampling of Ishizuka et al. (2003). Our MCS results are also recognized the recent lateral fault zone is located in east side of Shikoku Basin. We carried out high density grid multi-channel seismic reflection (MCS) survey using tuned airgun in order to obtain the relationship between the lateral faults and en-echelon arrangement in KR08-04 cruise. We identified the deformation of sediments in Shikoku Basin after activity of Kanbun seamount at 8 Ma in MCS profile. It is estimated to activate a part of the eastern side of Shikoku Basin after construction of en-echelon arrangement and termination of Shikoku Basin spreading. Based on analyses of magnetic and gravity anomalies, Yamazaki and Yuasa (1998

  6. Protective Effect of Proanthocyanidins from Sea Buckthorn (Hippophae Rhamnoides L.) Seed against Visible Light-Induced Retinal Degeneration in Vivo.

    PubMed

    Wang, Yong; Zhao, Liang; Huo, Yazhen; Zhou, Feng; Wu, Wei; Lu, Feng; Yang, Xue; Guo, Xiaoxuan; Chen, Peng; Deng, Qianchun; Ji, Baoping

    2016-01-01

    Dietary proanthocyanidins (PACs) as health-protective agents have become an important area of human nutrition research because of their potent bioactivities. We investigated the retinoprotective effects of PACs from sea buckthorn (Hippophae rhamnoides L.) seed against visible light-induced retinal degeneration in vivo. Pigmented rabbits were orally administered sea buckthorn seed PACs (50 and 100 mg/kg/day) for 14 consecutive days of pre-illumination and seven consecutive days of post-illumination. Retinal function was quantified via electroretinography 7 days after light exposure. Retinal damage was evaluated by measuring the thickness of the full-thickness retina and outer nuclear layer 7 days after light exposure. Sea buckthorn seed PACs significantly attenuated the destruction of electroretinograms and maintained the retinal structure. Increased retinal photooxidative damage was expressed by the depletion of glutathione peroxidase and catalase activities, the decrease of total antioxidant capacity level and the increase of malondialdehyde level. Light exposure induced a significant increase of inflammatory cytokines (IL-1β, TNF-α and IL-6) and angiogenesis (VEGF) levels in retina. Light exposure upregulated the expression of pro-apoptotic proteins Bax and caspase-3 and downregulated the expression of anti-apoptotic protein Bcl-2. However, sea buckthorn seed PACs ameliorated these changes induced by light exposure. Sea buckthorn seed PACs mediated the protective effect against light-induced retinal degeneration via antioxidant, anti-inflammatory and antiapoptotic mechanisms. PMID:27144578

  7. Protective Effect of Proanthocyanidins from Sea Buckthorn (Hippophae Rhamnoides L.) Seed against Visible Light-Induced Retinal Degeneration in Vivo.

    PubMed

    Wang, Yong; Zhao, Liang; Huo, Yazhen; Zhou, Feng; Wu, Wei; Lu, Feng; Yang, Xue; Guo, Xiaoxuan; Chen, Peng; Deng, Qianchun; Ji, Baoping

    2016-05-02

    Dietary proanthocyanidins (PACs) as health-protective agents have become an important area of human nutrition research because of their potent bioactivities. We investigated the retinoprotective effects of PACs from sea buckthorn (Hippophae rhamnoides L.) seed against visible light-induced retinal degeneration in vivo. Pigmented rabbits were orally administered sea buckthorn seed PACs (50 and 100 mg/kg/day) for 14 consecutive days of pre-illumination and seven consecutive days of post-illumination. Retinal function was quantified via electroretinography 7 days after light exposure. Retinal damage was evaluated by measuring the thickness of the full-thickness retina and outer nuclear layer 7 days after light exposure. Sea buckthorn seed PACs significantly attenuated the destruction of electroretinograms and maintained the retinal structure. Increased retinal photooxidative damage was expressed by the depletion of glutathione peroxidase and catalase activities, the decrease of total antioxidant capacity level and the increase of malondialdehyde level. Light exposure induced a significant increase of inflammatory cytokines (IL-1β, TNF-α and IL-6) and angiogenesis (VEGF) levels in retina. Light exposure upregulated the expression of pro-apoptotic proteins Bax and caspase-3 and downregulated the expression of anti-apoptotic protein Bcl-2. However, sea buckthorn seed PACs ameliorated these changes induced by light exposure. Sea buckthorn seed PACs mediated the protective effect against light-induced retinal degeneration via antioxidant, anti-inflammatory and antiapoptotic mechanisms.

  8. Protective Effect of Proanthocyanidins from Sea Buckthorn (Hippophae Rhamnoides L.) Seed against Visible Light-Induced Retinal Degeneration in Vivo

    PubMed Central

    Wang, Yong; Zhao, Liang; Huo, Yazhen; Zhou, Feng; Wu, Wei; Lu, Feng; Yang, Xue; Guo, Xiaoxuan; Chen, Peng; Deng, Qianchun; Ji, Baoping

    2016-01-01

    Dietary proanthocyanidins (PACs) as health-protective agents have become an important area of human nutrition research because of their potent bioactivities. We investigated the retinoprotective effects of PACs from sea buckthorn (Hippophae rhamnoides L.) seed against visible light-induced retinal degeneration in vivo. Pigmented rabbits were orally administered sea buckthorn seed PACs (50 and 100 mg/kg/day) for 14 consecutive days of pre-illumination and seven consecutive days of post-illumination. Retinal function was quantified via electroretinography 7 days after light exposure. Retinal damage was evaluated by measuring the thickness of the full-thickness retina and outer nuclear layer 7 days after light exposure. Sea buckthorn seed PACs significantly attenuated the destruction of electroretinograms and maintained the retinal structure. Increased retinal photooxidative damage was expressed by the depletion of glutathione peroxidase and catalase activities, the decrease of total antioxidant capacity level and the increase of malondialdehyde level. Light exposure induced a significant increase of inflammatory cytokines (IL-1β, TNF-α and IL-6) and angiogenesis (VEGF) levels in retina. Light exposure upregulated the expression of pro-apoptotic proteins Bax and caspase-3 and downregulated the expression of anti-apoptotic protein Bcl-2. However, sea buckthorn seed PACs ameliorated these changes induced by light exposure. Sea buckthorn seed PACs mediated the protective effect against light-induced retinal degeneration via antioxidant, anti-inflammatory and antiapoptotic mechanisms. PMID:27144578

  9. Antioxidant activities and xanthine oxidase inhibitory effects of extracts and main polyphenolic compounds obtained from Geranium sibiricum L.

    PubMed

    Wu, Nan; Zu, Yuangang; Fu, Yujie; Kong, Yu; Zhao, Jintong; Li, Xiaojuan; Li, Ji; Wink, Michael; Efferth, Thomas

    2010-04-28

    The antioxidant capacity and xanthine oxidase inhibitory effects of extracts and main polyphenolic compounds of Geranium sibiricum were studied in the present work. The antioxidant capacity was evaluated by ferric reducing antioxidant power, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, superoxide radical scavenging, nitric oxide scavenging, beta-carotene-linoleic acid bleaching, and reducing power assays. Among the extracts and four fractions, the ethyl acetate fraction showed the highest phenolic content (425.36 +/- 9.70 mg of gallic acid equivalent/g extracts) and the best antioxidant activity. The IC(50) values of the ethyl acetate fraction were 0.93, 3.32, 2.06, 2.66, and 1.64 microg/mL in the DPPH radical scavenging, superoxide radical scavenging, nitric oxide scavenging, beta-carotene-linoleic acid bleaching, and reducing power assays, respectively. Of the polyphenolic compounds separated from the ethyl acetate fraction, geraniin showed a higher activity than corilagin and gallic acid. The IC(50) values ranged from 0.87 to 2.53 microM, which were even lower than the positive control (except for allopurinol). All test samples except for the petroleum ether fraction showed xanthine oxidase inhibitory effects. We conclude that G. sibiricum represents a valuable natural antioxidant source and is potentially applicable in the healthy food industry.

  10. Arctic sea-ice melting: Effects on hydroclimatic variability and on UV-induced carbon cycling

    NASA Astrophysics Data System (ADS)

    Sulzberger, Barbara

    2016-04-01

    Since 1980 both the perennial and the multiyear central Arctic sea ice areas have declined by approximately 13 and 15% per decade, respectively (IPCC, 2013). Arctic sea-ice melting has led to an increase in the amplitude of the Northern Hemisphere jet stream and, as a consequence, in more slowly moving Rossby waves which results in blocking of weather patterns such as heat waves, droughts, cold spells, and heavy precipitation events (Francis and Vavrus, 2012). Changing Rossby waves account for more than 30% of the precipitation variability over several regions of the northern middle and high latitudes, including the US northern Great Plains and parts of Canada, Europe, and Russia (Schubert et al., 2011). From 2007 to 2013, northern Europe experienced heavy summer precipitation events that were unprecedented in over a century, concomitant with Arctic sea ice loss (Screen, 2013). Heavy precipitation events tend to increase the runoff intensity of terrigenous dissolved organic matter (tDOM) (Haaland et al., 2010). In surface waters tDOM is subject to UV-induced oxidation to produce atmospheric CO2. Mineralization of DOM also occurs via microbial respiration. However, not all chemical forms of DOM are available to bacterioplankton. UV-induced transformations generally increase the bioavailability of tDOM (Sulzberger and Durisch-Kaiser, 2009). Mineralization of tDOM is an important source of atmospheric CO2 and this process is likely to contribute to positive feedbacks on global warming (Erickson et al., 2015). However, the magnitudes of these potential feedbacks remain unexplored. This paper will discuss the following items: 1.) Links between Arctic sea-ice melting, heavy precipitation events, and enhanced tDOM runoff. 2.) UV-induced increase in the bioavailability of tDOM. 3.) UV-mediated feedbacks on global warming. References Erickson, D. J. III, B. Sulzberger, R. G. Zepp, A. T. Austin (2015), Effects of stratospheric ozone depletion, solar UV radiation, and climate

  11. Effect and potential mechanism of action of sea cucumber saponins on postprandial blood glucose in mice.

    PubMed

    Fu, Xueyuan; Wen, Min; Han, Xiuqing; Yanagita, Teruyoshi; Xue, Yong; Wang, Jingfeng; Xue, Changhu; Wang, Yuming

    2016-06-01

    Postprandial blood glucose control is the major goal in the treatment of diabetes. Here, we investigated the effect of sea cucumber saponins (SCSs) on postprandial blood glucose levels. SCS inhibited yeast as well as rat intestinal α-glucosidase activity in a dose-dependent manner and showed better inhibition of yeast α-glucosidases compared to the positive control. Further studies were performed using ICR mice treated with SCS and starch or SCS alone by oral gavage. Unexpectedly, SCS increased postprandial blood glucose levels a short time (1 h) after oral gavage. The serum corticosterone (CORT) level showed a consistent correlation with glucose levels. In vitro experiments confirmed that SCS treatment increased the secretion of CORT in the Y1 adrenal cell line. Overall, these studies demonstrated that SCS gavage could inhibit α-glucosidase activity but cannot attenuate postprandial blood glucose level within short time periods. The underlying mechanisms are probably related to increased serum CORT levels. PMID:26932154

  12. TBT pollution and effects in molluscs at US Virgin Islands, Caribbean Sea.

    PubMed

    Strand, Jakob; Jørgensen, Anne; Tairova, Zhanna

    2009-05-01

    An almost ubiquitous occurrence of imposex and butyltins in the molluscs from US Virgin Islands gives evidence to a widespread contamination with the antifouling agent tributyltin (TBT), which most likely is related to a relatively intense ship traffic. Three different muricid neogastropod species Thais deltoidea, Thais rustica and Purpura patula all seem to have potential as suitable and sensitive bioindicators for assessing levels and effects of TBT pollution in coastal areas including coral reefs in the Caribbean Sea. However, considerable interspecies differences in especially accumulation potential of butyltins were seen in this study. Furthermore, a high accumulation potential of TBT in the edible gastropod West Indian topshell (Cittarium pica) was found, despite that no signs of imposex were observed in this archaeogastropod species.

  13. Effect and potential mechanism of action of sea cucumber saponins on postprandial blood glucose in mice.

    PubMed

    Fu, Xueyuan; Wen, Min; Han, Xiuqing; Yanagita, Teruyoshi; Xue, Yong; Wang, Jingfeng; Xue, Changhu; Wang, Yuming

    2016-06-01

    Postprandial blood glucose control is the major goal in the treatment of diabetes. Here, we investigated the effect of sea cucumber saponins (SCSs) on postprandial blood glucose levels. SCS inhibited yeast as well as rat intestinal α-glucosidase activity in a dose-dependent manner and showed better inhibition of yeast α-glucosidases compared to the positive control. Further studies were performed using ICR mice treated with SCS and starch or SCS alone by oral gavage. Unexpectedly, SCS increased postprandial blood glucose levels a short time (1 h) after oral gavage. The serum corticosterone (CORT) level showed a consistent correlation with glucose levels. In vitro experiments confirmed that SCS treatment increased the secretion of CORT in the Y1 adrenal cell line. Overall, these studies demonstrated that SCS gavage could inhibit α-glucosidase activity but cannot attenuate postprandial blood glucose level within short time periods. The underlying mechanisms are probably related to increased serum CORT levels.

  14. Intermodel variations in projected precipitation change over the North Atlantic: Sea surface temperature effect

    NASA Astrophysics Data System (ADS)

    Long, Shang-Min; Xie, Shang-Ping

    2015-05-01

    Intermodel variations in future precipitation projection in the North Atlantic are studied using 23 state-of-art models from Phase 5 of the Coupled Model Intercomparison Project. Model uncertainty in annual mean rainfall change is locally enhanced along the Gulf Stream. The moisture budget analysis reveals that much of the model uncertainty in rainfall change can be traced back to the discrepancies in surface evaporation change and transient eddy effect among models. Results of the intermodel Singular Value Decomposition (SVD) analysis show that intermodel variations in local sea surface temperature (SST) pattern exert a strong control over the spread of rainfall projection among models through the modulation of evaporation change. The first three SVD modes explain more than 60% of the intermodel variance of rainfall projection and show distinct SST patterns with mode water-induced banded structures, reduced subpolar warming due to ocean dynamical cooling, and the Gulf Stream shift, respectively.

  15. Negative inotropic and chronotropic effects on the guinea pig atrium of extracts obtained from Averrhoa carambola L. leaves.

    PubMed

    Vasconcelos, C M L; Araújo, M S; Silva, B A; Conde-Garcia, E A

    2005-07-01

    It has been reported that star fruit can lead to a fatal outcome in uremic patients. The intoxication syndrome consists of hiccups, mental confusion, dizziness, and vomiting. On the other hand, folk medicine uses teas and infusions of carambola leaves to treat headache, vomiting, cough, insomnia, and diabetes. This motivated us to determine if Averrhoa carambola can act on the contractility and automaticity of the guinea pig heart. We measured the atrial isometric force in stimulated left atria and determined the chronotropic changes in spontaneously beating right atria. The carambola leaf extracts (1.5 mg/ml) abolished the contractile force in a concentration-dependent manner. Among the crude, methanolic, ethanolic, aqueous, and acetic extracts, the aqueous one was the most potent (EC50 = 520 +/- 94 microg/ml; flavonoids and tannins are the main constituents; Na+ and K+ contents in 1.0 mg/ml of aqueous extract were 0.12 +/- 0.016 and 1.19 +/- 0.15 mM, respectively). The aqueous extract abolished the positive Bowditch staircase phenomenon and reduced the inotropic response to CaCl2 (0.17-8.22 mM), events that are dependent on the cellular Ca2+ inward current. The adrenergic, muscarinic or opioid membrane receptors do not seem to participate in the mechanism of action of the cardioactive substance(s). In spontaneously beating atria, the aqueous extract promoted a negative chronotropic effect that was antagonized by 0.1 microM isoproterenol bitartrate. With this agonist, the EC50 of the aqueous extract increased from 133 +/- 58 to 650 +/- 100 microg/ml. These data regarding the effect of A. carambola on guinea pig atrial contractility and automaticity indicate an L-type Ca2+ channel blockade.

  16. Left ventricular diastolic filling improvement obtained by intravenous verapamil in mild to moderate essential hypertension: a complex effect.

    PubMed

    Franchi, F; Fabbri, G; Monopoli, A; Rossi, D; Matassi, L; Strazzulla, G; Bisi, G

    1989-01-01

    In order to try and evaluate through what prevailing mechanism verapamil (V) can induce an improvement in left ventricular (LV) diastolic early filling in mild to moderate essential hypertension, 43 properly classified essential hypertensives, aged 41-74 years (mean age 58.1 +/- 10.3), and 20 age-matched normotensives were studied. All subjects underwent both echocardiographic evaluation and 99mTc radionuclide angiocardiography in basal conditions between 8.00 a.m. and noon, after an overnight rest. In essential hypertensives gated equilibrium angiocardiography was repeated 3 and 30 min after i.v. V (0.1-mg/kg bolus, followed by 0.005 mg/kg/min for the period of radionuclide data acquisition). Simultaneously, supine arterial pressure was measured with a cuff manometer. In 36 essential hypertensives a phono-echo evaluation was obtained, both at 3 and 30 min after V, deriving a LV isovolumetric relaxation index (IRTI). Among diastolic early filling indices, we particularly considered the ratio of peak filling rate (PFR) to peak ejection rate (PER) in order to take into account the interaction of systolic performance with LV relaxation and diastolic early filling. Three minutes after V the increase in PFR (from 2.47 +/- 0.5 to 3.04 +/- 0.8 EDV/s, p less than 0.001) and the upwards tendency of PFR/PER were coupled with the enhancement in ejection fraction (from 61.1 +/- 13.3 to 63.9 +/- 13.8%, p less than 0.001) and heart rate (from 70.3 +/- 12.6 to 77.7 +/- 12.2 b/min, p less than 0.001) and with the reduction in mean arterial pressure (from 122 +/- 16 to 107 +/- 14 mm Hg, p less than 0.001), systemic arterial resistance index (from 3,234 +/- 968 to 2,432 +/- 678 dyn s cm-5 m2, p less than 0.001) and end-systolic volume index (from 32.9 +/- 17.1 to 31.5 +/- 18.3 ml/m2, p less than 0.02). On the contrary, 30 min after V, when systolic indices, heart rate, mean arterial pressure and systemic arterial resistance index had returned towards baseline values, PFR/PER showed

  17. Effects of sea surface temperature anomaly on flooding events in Hunan province

    NASA Astrophysics Data System (ADS)

    Hu, Xinjia; Wang, Ming

    2016-04-01

    This study investigated the effect of sea surface temperature anomaly (SSTA) on flood-season precipitation in Hunan Province (the main grain-producing area in China) and change trend of the related flooding events. Based on the observation data of flood seasons in 44 stations of Hunan province from 1970-2013 and the sea surface temperature (SST) dataset from the Met Office Hadley Center, the empirical orthogonal function (EOF) analysis, power spectrum analysis and correlation analytical method have been conducted to identify the key time and marine regions which influence flood-season rainfall distribution. According to these analyses, two main spatial patterns of precipitation have been observed. The first and remarkable pattern is generally distributed uniformly throughout the region and is characterized by a 2-3-year and 20-23-year periods. The decadal variability has a negative correlation with the summer SSTA in the Indian Ocean near the equator, while the interannual variability is associated with the previous autumn and winter SSTA in the eastern Pacific. The second pattern illustrates dry-wet difference, indicating a north-to-south opposite, in a 3-year periods. The key area for influencing this mode is distributed in the Equator Pacific especially in the previous autumn and winter (known as ENSO). Furthermore, based on the EOF results of precipitation, we introduced the historical flooding event records of Hunan province and developed the spatial distribution maps and probability density curves for the direct economic losses in the years of anomaly and normal rainfall. The results reveal that the anomaly years suffer more serious losses and there is a corresponding relationship between north-to-south opposite precipitation mode and regional economic loss differences. With the function of illustrating the variation trend of hazards and the critical influence factor, these results are the data foundation for flood risk assessment. It can be used as a

  18. Are Coastal Protected Areas Always Effective in Achieving Population Recovery for Nesting Sea Turtles?

    PubMed Central

    Nel, Ronel; Punt, André E.; Hughes, George R.

    2013-01-01

    Sea turtles are highly migratory and usually dispersed, but aggregate off beaches during the nesting season, rendering them vulnerable to coastal threats. Consequently, coastal Marine Protection Areas (MPAs) have been used to facilitate the recovery of turtle populations, but the effectiveness of these programs is uncertain as most have been operating for less than a single turtle generation (or<20 yr). South Africa, however, hosts one of the longest running conservation programs, protecting nesting loggerhead (Caretta caretta) and leatherback (Dermochelys coriacea) turtles since 1963 in a series of coastal MPAs. This provides a unique opportunity to evaluate the long-term effect of spatial protection on the abundance of two highly migratory turtle species with different life history characteristics. Population responses were assessed by modeling the number of nests over time in an index area (13 km) and an expanded monitoring area (53 km) with varying survey effort. Loggerhead abundance increased dramatically from∼250 to>1700 nests pa (index area) especially over the last decade, while leatherback abundance increased initially∼10 to 70 nests pa (index area), but then stabilized. Although leatherbacks have higher reproductive output per female and comparable remigration periods and hatching success to loggerheads, the leatherback population failed to expand. Our results suggest that coastal MPAs can work but do not guarantee the recovery of sea turtle populations as pressures change over time. Causes considered for the lack of population growth include factors in the MPA (expansion into unmonitored areas or incubation environment) of outside of the MPA (including carrying capacity and fishing mortality). Conservation areas for migratory species thus require careful design to account for species-specific needs, and need to be monitored to keep track of changing pressures. PMID:23671683

  19. Are coastal protected areas always effective in achieving population recovery for nesting sea turtles?

    PubMed

    Nel, Ronel; Punt, André E; Hughes, George R

    2013-01-01

    Sea turtles are highly migratory and usually dispersed, but aggregate off beaches during the nesting season, rendering them vulnerable to coastal threats. Consequently, coastal Marine Protection Areas (MPAs) have been used to facilitate the recovery of turtle populations, but the effectiveness of these programs is uncertain as most have been operating for less than a single turtle generation (or<20 yr). South Africa, however, hosts one of the longest running conservation programs, protecting nesting loggerhead (Caretta caretta) and leatherback (Dermochelys coriacea) turtles since 1963 in a series of coastal MPAs. This provides a unique opportunity to evaluate the long-term effect of spatial protection on the abundance of two highly migratory turtle species with different life history characteristics. Population responses were assessed by modeling the number of nests over time in an index area (13 km) and an expanded monitoring area (53 km) with varying survey effort. Loggerhead abundance increased dramatically from∼250 to>1700 nests pa (index area) especially over the last decade, while leatherback abundance increased initially∼10 to 70 nests pa (index area), but then stabilized. Although leatherbacks have higher reproductive output per female and comparable remigration periods and hatching success to loggerheads, the leatherback population failed to expand. Our results suggest that coastal MPAs can work but do not guarantee the recovery of sea turtle populations as pressures change over time. Causes considered for the lack of population growth include factors in the MPA (expansion into unmonitored areas or incubation environment) of outside of the MPA (including carrying capacity and fishing mortality). Conservation areas for migratory species thus require careful design to account for species-specific needs, and need to be monitored to keep track of changing pressures.

  20. Are coastal protected areas always effective in achieving population recovery for nesting sea turtles?

    PubMed

    Nel, Ronel; Punt, André E; Hughes, George R

    2013-01-01

    Sea turtles are highly migratory and usually dispersed, but aggregate off beaches during the nesting season, rendering them vulnerable to coastal threats. Consequently, coastal Marine Protection Areas (MPAs) have been used to facilitate the recovery of turtle populations, but the effectiveness of these programs is uncertain as most have been operating for less than a single turtle generation (or<20 yr). South Africa, however, hosts one of the longest running conservation programs, protecting nesting loggerhead (Caretta caretta) and leatherback (Dermochelys coriacea) turtles since 1963 in a series of coastal MPAs. This provides a unique opportunity to evaluate the long-term effect of spatial protection on the abundance of two highly migratory turtle species with different life history characteristics. Population responses were assessed by modeling the number of nests over time in an index area (13 km) and an expanded monitoring area (53 km) with varying survey effort. Loggerhead abundance increased dramatically from∼250 to>1700 nests pa (index area) especially over the last decade, while leatherback abundance increased initially∼10 to 70 nests pa (index area), but then stabilized. Although leatherbacks have higher reproductive output per female and comparable remigration periods and hatching success to loggerheads, the leatherback population failed to expand. Our results suggest that coastal MPAs can work but do not guarantee the recovery of sea turtle populations as pressures change over time. Causes considered for the lack of population growth include factors in the MPA (expansion into unmonitored areas or incubation environment) of outside of the MPA (including carrying capacity and fishing mortality). Conservation areas for migratory species thus require careful design to account for species-specific needs, and need to be monitored to keep track of changing pressures. PMID:23671683

  1. Photoprotective effect of coumarin and 3-hydroxycoumarin in sea urchin gametes and embryonic cells.

    PubMed

    de Araujo Leite, Jocelmo Cássio; de Castro, Tainá Myra Xavier; Barbosa-Filho, José Maria; de Siqueira-Junior, José Pinto; Marques-Santos, Luis Fernando

    2015-05-01

    Ultraviolet radiation B (UVB) represents 5% of all solar UV radiation and chronic exposure can induce harmful biological responses, including skin cancer. Prospection of new drugs with photoprotective properties and less toxic effects is constant and natural products have been the main options in this field. Coumarins are a group of natural phenolic compounds that shows several pharmacological activities. The aim of present work was to investigate the effect of coumarin and six derivatives in sea urchin gametes and zygotes exposed to UVB. Embryonic development assay was used to monitor UVB embryotoxicity. Firstly, we demonstrated that coumarin inhibited first embryonic cell division from 5 μM (EC50 = 52.9 μM) and its derivatives showed an embryotoxic effect ten times higher. Then, gametes or zygotes were treated with coumarin compounds before or after UVB exposure (UVB doses ranged from 0.056 to 0.9 kJm(-2)). Pretreatment of gametes or zygotes with coumarin or 3-hydroxycoumarin (1 μM, both) decreased UVB embryotoxic effect. Protective effect of the compounds was observed only when cells were treated previous to UVB exposure. Coumarin derivatives 4-hydroxycoumarin, 6-hydroxycoumarin, 7-hydroxycoumarin, 6,7-dihydroxycoumarin and 6-methoxy-7-hydroxycoumarin did not exhibit photoprotective activity. Our data provides evidences that coumarin and 3-hydroxycoumarin can be a promising class of photoprotective drugs.

  2. Assessing, planning, and management of North Sea oil development effects in the Shetland Islands

    SciTech Connect

    Nelson, J.G.; Butler, R.W. Univ. of Western Ontario, London, Ontario )

    1993-07-01

    The Shetland Islands have long had the reputation of having planned and managed the onshore effects of offshore petroleum development very well. The islands are seen as something of a model for others to follow and have frequently been visited since the beginning of northern North Sea oil development in the early 1970s by those wishing to learn how to best approach offshore petroleum development in their home areas. In this assessment the authors wish to focus on views expressed on the effectiveness of the planning and managing of onshore effects of petroleum development and present an overview of interviewee statements on future issues. Emphasis will be placed on the environmental aspects, where that term is taken for present purposes, to include fauna, flora, water quality, and other resources and their relationships to industries such as fishing and tourism--although observations will also be made about planning and management of land use and socio-economic effects. The paper concludes with an attempt to set their findings in a broader pluralist context by relating them to the views expressed in recent books by Shetland residents that contain observations on oil effects although written for more general purposes.

  3. Analysis and interpretation of transcriptomic data obtained from extended Warburg effect genes in patients with clear cell renal cell carcinoma

    PubMed Central

    Sanders, Edward; Diehl, Svenja

    2015-01-01

    Background Many cancers adopt a metabolism that is characterized by the well-known Warburg effect (aerobic glycolysis). Recently, numerous attempts have been made to treat cancer by targeting one or more gene products involved in this pathway without notable success. This work outlines a transcriptomic approach to identify genes that are highly perturbed in clear cell renal cell carcinoma (CCRCC). Methods We developed a model of the extended Warburg effect and outlined the model using Cytoscape. Following this, gene expression fold changes (FCs) for tumor and adjacent normal tissue from patients with CCRCC (GSE6344) were mapped on to the network. Gene expression values with FCs of greater than two were considered as potential targets for treatment of CCRCC. Results The Cytoscape network includes glycolysis, gluconeogenesis, the pentose phosphate pathway (PPP), the TCA cycle, the serine/glycine pathway, and partial glutaminolysis and fatty acid synthesis pathways. Gene expression FCs for nine of the 10 CCRCC patients in the GSE6344 data set were consistent with a shift to aerobic glycolysis. Genes involved in glycolysis and the synthesis and transport of lactate were over-expressed, as was the gene that codes for the kinase that inhibits the conversion of pyruvate to acetyl-CoA. Interestingly, genes that code for unique proteins involved in gluconeogenesis were strongly under-expressed as was also the case for the serine/glycine pathway. These latter two results suggest that the role attributed to the M2 isoform of pyruvate kinase (PKM2), frequently the principal isoform of PK present in cancer: i.e. causing a buildup of glucose metabolites that are shunted into branch pathways for synthesis of key biomolecules, may not be operative in CCRCC. The fact that there was no increase in the expression FC of any gene in the PPP is consistent with this hypothesis. Literature protein data generally support the transcriptomic findings. Conclusions A number of key genes have

  4. Quantifying the effect of sea level rise and flood defence - apoint process perspective on coastal flood damage

    NASA Astrophysics Data System (ADS)

    Boettle, M.; Rybski, D.; Kropp, J. P.

    2015-10-01

    In contrast to recent advances in projecting sea levels, estimations about the economic impact of sea level rise are vague. Nonetheless, they are of great importance for policy making with regard to adaptation and greenhouse-gas mitigation. Since the damage is mainly caused by extreme events, we propose a stochastic framework to estimate the monetary losses from coastal floods in a confined region. For this purpose, we follow a Peak-over-Threshold approach employing a Poisson point process and the Generalised Pareto Distribution. By considering the effect of sea level rise as well as potential adaptation scenarios on the involved parameters, we are able to study the development of the annual damage. An application to the city of Copenhagen shows that a doubling of losses can be expected from a mean sea level increase of only 11 cm. In general, we find that for varying parameters the expected losses can be well approximated by one of three analytical expressions depending on the extreme value parameters. These findings reveal the complex interplay of the involved parameters and allow conclusions of fundamental relevance. For instance, we show that the damage always increases faster than the sea level rise itself. This in turn can be of great importance for the assessment of sea level rise impacts on the global scale. Our results are accompanied by an assessment of uncertainty, which reflects the stochastic nature of extreme events. While the uncertainty of flood damage increases with rising sea levels, we find that the error of our estimations in relation to the expected damage decreases.

  5. Quantifying the effect of sea level rise and flood defence - a point process perspective on coastal flood damage

    NASA Astrophysics Data System (ADS)

    Boettle, M.; Rybski, D.; Kropp, J. P.

    2016-02-01

    In contrast to recent advances in projecting sea levels, estimations about the economic impact of sea level rise are vague. Nonetheless, they are of great importance for policy making with regard to adaptation and greenhouse-gas mitigation. Since the damage is mainly caused by extreme events, we propose a stochastic framework to estimate the monetary losses from coastal floods in a confined region. For this purpose, we follow a Peak-over-Threshold approach employing a Poisson point process and the Generalised Pareto Distribution. By considering the effect of sea level rise as well as potential adaptation scenarios on the involved parameters, we are able to study the development of the annual damage. An application to the city of Copenhagen shows that a doubling of losses can be expected from a mean sea level increase of only 11 cm. In general, we find that for varying parameters the expected losses can be well approximated by one of three analytical expressions depending on the extreme value parameters. These findings reveal the complex interplay of the involved parameters and allow conclusions of fundamental relevance. For instance, we show that the damage typically increases faster than the sea level rise itself. This in turn can be of great importance for the assessment of sea level rise impacts on the global scale. Our results are accompanied by an assessment of uncertainty, which reflects the stochastic nature of extreme events. While the absolute value of uncertainty about the flood damage increases with rising mean sea levels, we find that it decreases in relation to the expected damage.

  6. The effect of temperature and heating rate on char properties obtained from solar pyrolysis of beech wood.

    PubMed

    Zeng, Kuo; Minh, Doan Pham; Gauthier, Daniel; Weiss-Hortala, Elsa; Nzihou, Ange; Flamant, Gilles

    2015-04-01

    Char samples were produced from pyrolysis in a lab-scale solar reactor. The pyrolysis of beech wood was carried out at temperatures ranging from 600 to 2000°C, with heating rates from 5 to 450°C/s. CHNS, scanning electron microscopy analysis, X-ray diffractometry, Brunauer-Emmett-Teller adsorption were employed to investigate the effect of temperature and heating rate on char composition and structure. The results indicated that char structure was more and more ordered with temperature increase and heating rate decrease (higher than 50°C/s). The surface area and pore volume firstly increased with temperature and reached maximum at 1200°C then reduced significantly at 2000°C. Besides, they firstly increased with heating rate and then decreased slightly at heating rate of 450°C/s when final temperature was no lower than 1200°C. Char reactivity measured by TGA analysis was found to correlate with the evolution of char surface area and pore volume with temperature and heating rate.

  7. Effects of dihydroquercetin obtained from deodar (Cedrus deodara) on immune status of gilthead seabream (Sparus aurata L.).

    PubMed

    Awad, Elham; Awaad, Amani S; Esteban, M Angeles

    2015-03-01

    The use of medicinal plants as prophylactic method in fish is considered safe and a very promising alternative to the use of chemicals in aquaculture practices. The prospective mode of action of dihydroquercetin, fraction of the medical plant deodar (Cedrus deodara), was evaluated on immune status of gilthead seabream (Sparus aurata L.). Fish were divided into 4 groups before being fed for 14 days with commercial diets supplemented with 0% (control), 0.1%, 0.5% and 1% of dihydroquercetin. Cellular (phagocytosis and respiratory burst activities) and humoral (seric complement activity, antiprotease, total protein, peroxidase, bactericidal activity and IgM level) immune parameters were investigated. The results recorded enhancement in all the tested parameters and in all the dihydroquercetin supplemented groups compared to the control. Interestingly, the fish received the lowest dose of dihydroquercetin (0.1%) showed a highly significant difference (p < 0.05) in phagocytosis, respiratory burst, IgM level, total protein, complement, antiprotease and bactericidal activities compared to the control. Direct effect of different doses of dihydroquercetin on head-kidney leucocytes was also studied in a previous in vitro assay. Again, the lowest doses tested provoked the highest immune cellular activities, where, the highest phagocytic and respiratory bust activities were recorded in leucocytes incubated with 0.025% and 0.0125% doses, respectively. Therefore, the results suggest that low concentrations of dihydroquercetin as food supplements are able to increase the immune status of gilthead seabream.

  8. Characterization of biochar obtained from weeds and its effect on soil properties of North Eastern Region of India.

    PubMed

    Mandal, S; Verma, B C; Ramkrushna, G I; Singh, R K; Rajkhowa, D J

    2015-03-01

    In the global climate change scenario, application of biochar in soil has become one of the important management practices for carbon sequestration, soil health improvement and climate change mitigation. In this study, an attempt was made to see the effect of biochar prepared from weed biomass on soil properties in subtropical northeast India. Biochar were prepared from seven locally available weed biomass viz. Ageratum conyzoides, Lantana camera, Gynura sp., Setaria sp., Avena fatua, Maize stalk, Pine needles and were characterised. Apot experiment was conducted with maize, where biochar was applied alone and in combination with fertilizers. Results revealed that biochar had significant impact on soil pH, SOC, and available nutrients like N, P and K. It also had significant impact on maize biomass yield. All biochar contained more than 50% stable carbon. Increase in soil pH was in the range of 0.26 to 0.3 and that of SOC from 1.62% in control to 1.74% in biochar added treatments. Biochars alone improved the available nitrogen ranging from 4.5 to 21.3 mg kg(-1), available P from 3.32 to 3.68 mg kg(-1) and increased K content by 20% above control. Weed biomass can be potential alternative to enhance soil and crop productivity through conversion into biochar.

  9. Effects of storage time on total protein and globulin concentrations in bovine fresh frozen plasma obtained for transfusion.

    PubMed

    Proverbio, D; Spada, E; Baggiani, L; Bagnagatti De Giorgi, G; Roggero, N; Belloli, A; Pravettoni, D; Perego, R

    2015-01-01

    To evaluate the effects of storage conditions on total protein (TP) and globulin fractions in fresh frozen bovine plasma units prepared and stored for transfusion, TP and globulin fractions were evaluated in fresh plasma and at 1 month and 6 and 12 months after blood collection in plasma stored at -20°C. Significant differences in concentrations were found in the median concentration of total protein (P=0.0336), between 0 months and 1 month (P=0.0108), 0 and 6 months (P=0.0023), and 0 and 12 months (P=0.0027), in mean concentration (g/dL) of albumin (P=0.0394), between 0 months and 1 month (P=0.0131), 0 and 6 months (P=0.0035), and 0 and 12 months (P=0.0038), and beta-2 fraction (P=0.0401), between 0 and 6 months (P=0.0401) and 0 and 12 months (P=0.0230). This study suggests that total gamma globulin concentration in bovine frozen plasma is stable for 12 months at -20°C. Total protein, ALB, and beta-2 fraction have significantly different concentrations (g/dL) when compared to prestorage. This study has shown IgG protein fraction stability in bovine fresh frozen plasma collected for transfusion; therefore, bovine fresh frozen plasma seems to be suitable for the treatment of hypogammaglobulinemia (failure of passive transfer) in calves when stored for 12 months at -20°C.

  10. Effects of Storage Time on Total Protein and Globulin Concentrations in Bovine Fresh Frozen Plasma Obtained for Transfusion

    PubMed Central

    Proverbio, D.; Spada, E.; Baggiani, L.; Bagnagatti De Giorgi, G.; Roggero, N.; Belloli, A.; Pravettoni, D.; Perego, R.

    2015-01-01

    To evaluate the effects of storage conditions on total protein (TP) and globulin fractions in fresh frozen bovine plasma units prepared and stored for transfusion, TP and globulin fractions were evaluated in fresh plasma and at 1 month and 6 and 12 months after blood collection in plasma stored at −20°C. Significant differences in concentrations were found in the median concentration of total protein (P = 0.0336), between 0 months and 1 month (P = 0.0108), 0 and 6 months (P = 0.0023), and 0 and 12 months (P = 0.0027), in mean concentration (g/dL) of albumin (P = 0.0394), between 0 months and 1 month (P = 0.0131), 0 and 6 months (P = 0.0035), and 0 and 12 months (P = 0.0038), and beta-2 fraction (P = 0.0401), between 0 and 6 months (P = 0.0401) and 0 and 12 months (P = 0.0230). This study suggests that total gamma globulin concentration in bovine frozen plasma is stable for 12 months at −20°C. Total protein, ALB, and beta-2 fraction have significantly different concentrations (g/dL) when compared to prestorage. This study has shown IgG protein fraction stability in bovine fresh frozen plasma collected for transfusion; therefore, bovine fresh frozen plasma seems to be suitable for the treatment of hypogammaglobulinemia (failure of passive transfer) in calves when stored for 12 months at −20°C. PMID:25767825

  11. Effects of Perivitelline Fluid Obtained from Horseshoe Crab on The Proliferation and Genotoxicity of Dental Pulp Stem Cells

    PubMed Central

    Musa, Marahaini; Mohd Ali, Khadijah; Kannan, Thirumulu Ponnuraj; Azlina, Ahmad; Omar, Nor Shamsuria; Chatterji, Anil; Mokhtar, Khairani Idah

    2015-01-01

    Objective Perivitelline fluid (PVF) of the horseshoe crab embryo has been reported to possess an important role during embryogenesis by promoting cell proliferation. This study aims to evaluate the effect of PVF on the proliferation, chromosome aberration (CA) and mutagenicity of the dental pulp stem cells (DPSCs). Materials and Methods This is an in vitro experimental study. PVF samples were collected from horseshoe crabs from beaches in Malaysia and the crude extract was prepared. DPSCs were treated with different concentrations of PVF crude extract in an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay (cytotoxicity test). We choose two inhibitory concentrations (IC50 and IC25) and two PVF concentrations which produced more cell viability compared to a negative control (100%) for further tests. Quantitative analysis of the proliferation activity of PVF was studied using the AlamarBlue®assay for 10 days. Population doubling times (PDTs) of the treatment groups were calculated from this assay. Genotoxicity was evaluated based on the CA and Ames tests. Statistical analysis was carried out using independent t test to calculate significant differences in the PDT and mitotic indices in the CA test between the treatment and negative control groups. Significant differences in the data were P<0.05. Results A total of four PVF concentrations retrieved from the MTT assay were 26.887 mg/ml (IC50), 14.093 mg/ml (IC25), 0.278 mg/ml (102% cell viability) and 0.019 mg/ml (102.5% cell viability). According to the AlamarBlue®assay, these PVF groups produced comparable proliferation activities compared to the negative (untreated) control. PDTs between PVF groups and the negative control were insignificantly different (P>0.05). No significant aberrations in chromosomes were observed in the PVF groups and the Ames test on the PVF showed the absence of significant positive results. Conclusion PVF from horseshoe crabs produced insignificant proliferative

  12. Tidal cooling effect on SST and its influence on typhoon simulation over the East China Sea

    NASA Astrophysics Data System (ADS)

    Zong, H.; WU, H.

    2013-12-01

    Each summer, tropical cyclones (including typhoon) frequently travel across the East China Sea (ECS), beating the surrounding regions with massive damages. Therefore, it is very important to predict their intensities and tracks by using numerical models, so as to advise people to evacuate from the possible affected area. Unfortunately, forecasting the typhoon is still a big challenge since a couple of reasons. To numerically predict the typhoons, an atmosphere-ocean coupling model is often required. Researchers have done many efforts on the atmosphere part to improve the accuracy, while the ocean part was often treated simply. For example, many operational forecasting models simply set the SST as climatological values. As the ocean motion is energetic and the sea conditions vary significantly with time, this brief setting could result in some error. Some other models include an ocean model that considering the air-sea exchange of heat and momentum, as well as large-scale ocean motions like circulation. However, in the shallow coastal oceans like the ECS, tidal forcing also plays an important role that modulate the vertical exchange to adjust the SST. So far no atmosphere-ocean coupling model in this region consider the tide. In this study, we have found that 1) Accuracy of SST is essential to correctly predict the intensity and track of typhoons; 2) It is important to include the tide to correctly simulate the SST in the shallow oceans like the ECS. We setup an Advanced Research Hurricane WRF (WRF-AHW) model in the ECS and simulated typhoon Muifa (No. 201109). The 6-hourly data of the NCEP FNL Global Analyses was used as the initial and lateral boundary conditions in the model. Firstly, We run the model only with NCEP FNL Global Analyses data. The simulated track was very similar to China forecasted one, which was more than 200 kilometers far from the Joint Typhoon Warning Center (JTWC) provided typhoon location at 0:00 am, 6 August, 2011. Then, We run the model

  13. Ecological Effects of Sea Level Rise: Advancing coastal management through integrated research and engagement

    NASA Astrophysics Data System (ADS)

    Kidwell, D. M.

    2012-12-01

    Rising sea level represents a significant threat to coastal communities and ecosystems through land loss, altered habitats, and increased vulnerability to coastal storms and inundation. This threat is exemplified in the northern Gulf of Mexico where low topography, expansive marshes, and a prevalence of tropical storms have already resulted in extensive coastal impacts. The development of robust predictive capabilities that incorporate complex biological processes with physical dynamics are critical for informed planning and restoration efforts for coastal ecosystems. Looking to build upon existing predictive modeling capabilities and allow for use of multiple model (i.e., ensemble) approaches, NOAA initiated the Ecological Effects of Sea Level Rise program in 2010 to advance physical/biological integrative modeling capabilities in the region with a goal to provide user friendly predictive tools for coastal ecosystem management. Focused on the northern Gulf of Mexico, this multi-disciplinary project led by the University of Central Florida will use in situ field studies to parameterize physical and biological models. These field studies will also result in a predictive capability for overland sediment delivery and transport that will further enhance marsh, oyster, and submerged aquatic vegetation models. Results from this integrated modeling effort are envisioned to inform management strategies for reducing risk, restoration and breakwater guidelines, and resource sustainability for project planning, among other uses. In addition to the science components, this project incorporates significant engagement of the management community through a management applications principle investigator and an advisory management committee. Routine engagement between the science team and the management committee, including annual workshops, are focused on ensuring the development of applicable, relevant, and useable products and tools at the conclusion of this project. Particular

  14. Effect of phenol on embryo development and expression of metallothionein in the sea urchin Hemicentrotus pulcherrimus

    NASA Astrophysics Data System (ADS)

    Hwang, Un-Ki; Lee, Ju-Wook; Ryu, Hyang-Mi; Kang, Ju-Chan; Kang, Han Seung

    2015-12-01

    In this study, we identified and cloned the sea urchin Hemicentrotus pulcherrimus MT (Hp-MT) mRNA. We examined the gameto- and embryo-toxic effects and the expression of Hp-MT mRNA at various concentrations of phenol in H. pulcherrimus. We found that the normal embryogenesis rate was significantly inhibited when H. pulcherrimus was exposed to phenol (EC50 = 1565.86 ppb, 95% Cl = 1183.47-2037.84 ppb). The no observed effective concentration (NOEC) and the lowest observed effective concentration (LOEC) of the normal embryogenesis rate were < 10 ppb and 100 ppb, respectively. Hp-MT cDNA is 651 bp in length and encodes a protein of 64 amino acids. We found that the expression of Hp-MT mRNA was significantly increased with phenol treatment in a concentrationdependent manner. These results suggest that phenol at greater than 100 ppb has a toxic effect during the early embryonic stages of H. pulcherrimus, and MT mRNA may be used as a biomarker for risk assessment of phenol contamination.

  15. Mississippi River and Sea Surface Height Effects on Oil Slick Migration

    PubMed Central

    Falcini, Frederico; Jerolmack, Douglas J.; Buongiorno Nardelli, Bruno

    2012-01-01

    Millions of barrels of oil escaped into the Gulf of Mexico (GoM) after the 20 April, 2010 explosion of Deepwater Horizon (DH). Ocean circulation models were used to forecast oil slick migration in the GoM, however such models do not explicitly treat the effects of secondary eddy-slopes or Mississippi River (MR) hydrodynamics. Here we report oil front migration that appears to be driven by sea surface level (SSL) slopes, and identify a previously unreported effect of the MR plume: under conditions of relatively high river discharge and weak winds, a freshwater mound can form around the MR Delta. We performed temporal oil slick position and altimeter analysis, employing both interpolated altimetry data and along-track measurements for coastal applications. The observed freshwater mound appears to have pushed the DH oil slick seaward from the Delta coastline. We provide a physical mechanism for this novel effect of the MR, using a two-layer pressure-driven flow model. Results show how SSL variations can drive a cross-slope migration of surface oil slicks that may reach velocities of order km/day, and confirm a lag time of order 5–10 days between mound formation and slick migration, as observed form the satellite analysis. Incorporating these effects into more complex ocean models will improve forecasts of slick migration for future spills. More generally, large SSL variations at the MR mouth may also affect the dispersal of freshwater, nutrients and sediment associated with the MR plume. PMID:22558317

  16. Dual effect of procaine in sea urchin eggs. Inducer and inhibitor of microtubule assembly.

    PubMed

    Coffe, G; Foucault, G; Raymond, M N; Pudles, J

    1985-01-01

    An increase in the amount of cytoplasmic filamentous structures (cytoplasmic matrix and aster) which were recovered after hexylene glycol/Triton X-100 treatment of sea urchin eggs (Paracentrotus lividus) activated by 0.2-2.5 mM procaine was observed. At higher activator concentrations, an opposite effect was observed and formation of these cytoplasmic structures was inhibited in the presence of 10 mM procaine. This inhibitory effect was reversed by diluting the drug in the incubation medium. DNase I inhibition assays on egg homogenates which were performed at different time points of the activation process, show that the same amount of actin was induced to polymerize in eggs activated either by 2.5 or 10 mM procaine. However, colchicine-binding assays on the 100 000 g particulate fractions of these homogenates show that in eggs activated by 10 mM procaine, in contrast to those activated by 2.5 mM, tubulin polymerization was inhibited and microtubules were disassembled. These results show that the dual effect of procaine in the organization of the egg cytoskeleton appears to be related to its effect on the state of tubulin. PMID:4038386

  17. Mississippi River and sea surface height effects on oil slick migration.

    PubMed

    Falcini, Frederico; Jerolmack, Douglas J; Nardelli, Bruno Buongiorno

    2012-01-01

    Millions of barrels of oil escaped into the Gulf of Mexico (GoM) after the 20 April, 2010 explosion of Deepwater Horizon (DH). Ocean circulation models were used to forecast oil slick migration in the GoM, however such models do not explicitly treat the effects of secondary eddy-slopes or Mississippi River (MR) hydrodynamics. Here we report oil front migration that appears to be driven by sea surface level (SSL) slopes, and identify a previously unreported effect of the MR plume: under conditions of relatively high river discharge and weak winds, a freshwater mound can form around the MR Delta. We performed temporal oil slick position and altimeter analysis, employing both interpolated altimetry data and along-track measurements for coastal applications. The observed freshwater mound appears to have pushed the DH oil slick seaward from the Delta coastline. We provide a physical mechanism for this novel effect of the MR, using a two-layer pressure-driven flow model. Results show how SSL variations can drive a cross-slope migration of surface oil slicks that may reach velocities of order km/day, and confirm a lag time of order 5-10 days between mound formation and slick migration, as observed form the satellite analysis. Incorporating these effects into more complex ocean models will improve forecasts of slick migration for future spills. More generally, large SSL variations at the MR mouth may also affect the dispersal of freshwater, nutrients and sediment associated with the MR plume. PMID:22558317

  18. Effects of sea hare ink secretion and its escapin-generated components on a variety of predatory fishes.

    PubMed

    Nusnbaum, Matthew; Derby, Charles D

    2010-06-01

    Sea hares, Aplysia californica, have a diversity of anti-predatory defenses. One is an actively released chemical defense: an ink secretion that is a mixture of two glandular products--ink from the ink gland and opaline from the opaline gland. The mechanisms of action of ink secretion and its components have recently been examined in detail against several predatory invertebrates. Our goal is to extend this mechanistic analysis to predatory vertebrates. Toward this end, the current study details the effects of ink, opaline, and one set of its components--the products of the reaction of escapin, an l-amino acid oxidase, with its natural substrates, L-lysine and L-arginine--on the palatability of food for five species of fishes: bluehead wrasses Thalassoma bifasciatum, señorita wrasses Oxyjulis californica, pinfish Lagodon rhomboides, mummichogs Fundulus heteroclitus, and bonnethead sharks Sphyrna tiburo. These fishes have different feeding styles, ranging from large fishes able to engulf sea hares to smaller fishes able to attack sea hares by pecking at them; and they live in a variety of habitats, including those that sea hares typically inhabit. We show that ink but not opaline significantly decreases the palatability of food for all five species, and that escapin products are mildly unpalatable to the two species of wrasses but not to the other species. These results, together with others, show that sea hare ink affects a diversity of predatory fishes, setting the stage for mechanistic studies using electrophysiological analysis of their chemosensory systems.

  19. Marine downscaling of a future climate scenario in the North Sea and possible effects on dinoflagellate harmful algal blooms.

    PubMed

    Friocourt, Y F; Skogen, M; Stolte, W; Albretsen, J

    2012-01-01

    Two hydrodynamic and ecological models were used to investigate the effects of climate change-according to the IPCC A1b emission scenario - on the primary productivity of the North Sea and on harmful algal blooms. Both models were forced with atmospheric fields from a regional downscaling of General Circulation Models to compare two sets of 20-year simulations representative of present climate (1984-2004) conditions and of the 2040s. Both models indicated a general warming of the North Sea by up to 0.8°C and a slight freshening by the 2040s. The models suggested that the eastern North Sea would be subjected to more temperature and salinity changes than the western part. In addition, the ecological modules of the models indicated that the warming up of the sea would result in a slightly earlier spring bloom. The one model that also computes the distribution of four different phytoplankton groups suggests an increase in the abundance of dinoflagellates, whereas the abundance of diatoms, flagellates and Phaeocystis sp. remains comparable to current levels, or decrease. Assuming that Dinophysis spp. would experience a similar increase in abundance as the modelled group of dinoflagellates, it is hypothesised that blooms of Dinophysis spp. may occur more frequently in the North Sea by 2040. However, implications for shellfish toxicity remain unclear.

  20. Effect of modified atmosphere packaging (map) on the quality of sea buckthorn berry fruits during postharvest storage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of modified atmosphere packaging (MAP) on the quality of the berry fruits of sea buckthorn (SBT) during refrigerated storage was investigated. SBT berries were packaged in 160 and 525 oxygen transmission rate (OTR) films or in vented clamshell containers (air control) and stored at 10C fo...

  1. Differential Effects of Sex Pheromone Compounds on Adult Female Sea Lamprey (Petromyzon marinus) Locomotor Patterns.

    PubMed

    Walaszczyk, Erin J; Goheen, Benjamin B; Steibel, Juan Pedro; Li, Weiming

    2016-06-01

    Synchronization of male and female locomotor activity plays a critical role in ensuring reproductive success, especially in semelparous species. The goal of this study was to elucidate the effects of individual chemical signals, or pheromones, on the locomotor activity in the sea lamprey (Petromyzon marinus). In their native habitat, adult preovulated females (POF) and ovulated females (OF) are exposed to sex pheromone compounds that are released from spermiated males and attract females to nests during their migration and spawning periods. In this study, locomotor activity of individual POF and OF was measured hourly in controlled laboratory conditions using an automated video-tracking system. Differences in the activity between a baseline day (no treatment exposure) and a treatment day (sex pheromone compound or control exposure) were examined for daytime and nighttime periods. Results showed that different pheromone compound treatments affected both POF and OF sea lamprey (p < 0.05) but in different ways. Spermiated male washings (SMW) and one of its main components, 7α,12α,24-trihydroxy-5α-cholan-3-one 24 sulfate (3kPZS), decreased activity of POF during the nighttime. SMW also reduced activity in POF during the daytime. In contrast, SMW increased activity of OF during the daytime, and an additional compound found in SMW, petromyzonol sulfate (PZS), decreased the activity during the nighttime. In addition, we examined factors that allowed us to infer the overall locomotor patterns. SMW increased the maximum hourly activity during the daytime, decreased the maximum hourly activity during the nighttime, and reduced the percentage of nocturnal activity in OF. Our findings suggest that adult females have evolved to respond to different male compounds in regards to their locomotor activity before and after final maturation. This is a rare example of how species-wide chemosensory stimuli can affect not only the amounts of activity but also the overall locomotor

  2. Teratogenic Effects of Diatom Metabolites on Sea Urchin Paracentrotus lividus Embryos

    PubMed Central

    Romano, Giovanna; Miralto, Antonio; Ianora, Adrianna

    2010-01-01

    The diatom-derived polyunsaturated aldehydes (PUAs), 2-trans,4-trans-decadienal, 2-trans,4-trans-octadienal, 2-trans,4-trans,7-octatrienal, 2-trans,4-trans-heptadienal, as well as tridecanal were tested on early and later larval development in the sea urchin Paracentrotus lividus. We also tested the effect of some of the more abundant diatom polyunsaturated fatty acids (PUFAs) on development, in particular 5,8,11,14,17-eicosapentaenoic acid (EPA), one of the main precursors of diatom PUAs, as well as 4,7,10,13,16,19-docosahexaenoic acid (DHA), 6,9,12,15-octadecatetraenoic acid (stearidonic acid), 6,9,12-octadecatrienoic acid (γ-linolenic acid) and 9,12-octadecadienoic acid (linoleic acid). PUAs blocked sea urchin cell cleavage in a dose dependent manner and with increasing chain length from C7 to C10 PUAs, with arrest occurring at 27.27 μM with heptadienal, 16.13 μM with octadienal, 11.47 μM with octatrienal and 5.26 μM with decadienal. Of the PUFAs tested, only EPA and stearidonic acid blocked cleavage, but at much higher concentrations compared to PUAs (331 μM for EPA and 181 μM for stearidonic acid). Sub-lethal concentrations of decadienal (1.32–5.26 μM) delayed development of embryos and larvae which showed various degrees of malformations depending on the concentrations tested. Sub-lethal concentrations also increased the proportion of TUNEL-positive cells indicating imminent death in embryos and larvae. Using decadienal as a model PUA, we show that this aldehyde can be detected spectrophotometrically for up to 14 days in f/2 medium. PMID:20479962

  3. Effects of sustained exercise on GH-IGFs axis in gilthead sea bream (Sparus aurata).

    PubMed

    Vélez, Emilio J; Azizi, Sheida; Millán-Cubillo, Antonio; Fernández-Borràs, Jaume; Blasco, Josefina; Chan, Shu Jin; Calduch-Giner, Josep A; Pérez-Sánchez, Jaume; Navarro, Isabel; Capilla, Encarnación; Gutiérrez, Joaquim

    2016-02-15

    The endocrine system regulates growth mainly through the growth hormone (GH)/insulin-like growth factors (IGFs) axis and, although exercise promotes growth, little is known about its modulation of these factors. The aim of this work was to characterize the effects of 5 wk of moderate sustained swimming on the GH-IGFs axis in gilthead sea bream fingerlings. Plasma IGF-I/GH ratio and tissue gene expression of total IGF-I and three splice variants, IGF-II, three IGF binding proteins, two GH receptors, two IGF-I receptors, and the downstream molecules were analyzed. Fish under exercise (EX) grew more than control fish (CT), had a higher plasma IGF-I/GH ratio, and showed increased hepatic IGF-I expression (mainly IGF-Ia). Total IGF-I expression levels were similar in the anterior and caudal muscles; however, IGF-Ic expression increased with exercise, suggesting that this splice variant may be the most sensitive to mechanical action. Moreover, IGFBP-5b and IGF-II increased in the anterior and caudal muscles, respectively, supporting enhanced muscle growth. Furthermore, in EX fish, hepatic IGF-IRb was reduced together with both GHRs; GHR-II was also reduced in anterior muscle, while GHR-I showed higher expression in the two muscle regions, indicating tissue-dependent differences and responses to exercise. Exercise also increased gene and protein expression of target of rapamycin (TOR), suggesting enhanced muscle protein synthesis. Altogether, these data demonstrate that moderate sustained activity may be used to increase the plasma IGF-I/GH ratio and to potentiate growth in farmed gilthead sea bream, modulating the gene expression of different members of the GH-IGFs axis (i.e., IGF-Ic, IGF-II, IGFBP-5b, GHR-I, and TOR).

  4. Effects of small-scale heterogeneities on the bulk mechanical properties of sea ice

    NASA Astrophysics Data System (ADS)

    Song, A.

    2015-12-01

    The Arctic ice cover is riddled with cracks, ridges, and melt ponds leading to spatial heterogeneities that manifest as sharp transitions in thickness, porosity, salinity, etc., that in turn affect the bulk mechanical behavior of the ice pack. In regions within and near the marginal ice zone, where ice survives the summer melt and break-up as discrete floes with length scales on the order of hundreds of meters to a kilometer, the freeze up subsequent to the melt season forms a patchwork of thick perennial ice bound together by thinner and smoother first-year ice with a coherence of varying length scales. Remote sensing has shown that the fracture patterns in these patchy ice regions, which may be more representative of marginal ice zone and coastal areas, tend to form in preferential pathways in the thinner ice, therefore modifying the rhomboidal pattern that is characteristic of more homogeneous ice. Using a sea ice model based on the discrete element method (DEM) and remotely sensed images, we examine the effect that heterogeneities in the ice cover have on the derivation of constitutive behavior at scales relevant to climate models by representing the observed heterogeneities explicitly. This model allows us to not only measure the mechanical response of a sample domain, but to also look at the break-up behavior for regions of varying melt pond coverage, thickness, etc. Our hope is that our results can be used to extend existing sea ice rheologies that already incorporate the spatial discontinuities of the ice cover due to lead formation [Moritz & Ukita, 2000; Schreyer et al., 2006; Wilchinsky & Feltham, 2004; Sedlacek et al., 2007].

  5. Effect of hypoxic "dose" on physiological responses and sea-level performance.

    PubMed

    Wilber, Randall L; Stray-Gundersen, James; Levine, Benjamin D

    2007-09-01

    Live high-train low (LH+TL) altitude training was developed in the early 1990s in response to potential training limitations imposed on endurance athletes by traditional live high-train high (LH+TH) altitude training. The essence of LH+TL is that it allows athletes to "live high" for the purpose of facilitating altitude acclimatization, as manifest by a profound and sustained increase in endogenous erythropoietin (EPO) and ultimately an augmented erythrocyte volume, while simultaneously allowing athletes to "train low" for the purpose of replicating sea-level training intensity and oxygen flux, thereby inducing beneficial metabolic and neuromuscular adaptations. In addition to "natural/terrestrial" LH+TL, several simulated LH+TL devices have been developed to conveniently bring the mountain to the athlete, including nitrogen apartments, hypoxic tents, and hypoxicator devices. One of the key questions regarding the practical application of LH+TL is, what is the optimal hypoxic dose needed to facilitate altitude acclimatization and produce the expected beneficial physiological responses and sea-level performance effects? The purpose of this paper is to objectively answer that question, on the basis of an extensive body of research by our group in LH+TL altitude training. We will address three key questions: 1) What is the optimal altitude at which to live? 2) How many days are required at altitude? and 3) How many hours per day are required? On the basis of consistent findings from our research group, we recommend that for athletes to derive the physiological benefits of LH+TL, they need to live at a natural elevation of 2000-2500 m for >or=4 wk for >or=22 h.d(-1).

  6. Effect of hypoxic "dose" on physiological responses and sea-level performance.

    PubMed

    Wilber, Randall L; Stray-Gundersen, James; Levine, Benjamin D

    2007-09-01

    Live high-train low (LH+TL) altitude training was developed in the early 1990s in response to potential training limitations imposed on endurance athletes by traditional live high-train high (LH+TH) altitude training. The essence of LH+TL is that it allows athletes to "live high" for the purpose of facilitating altitude acclimatization, as manifest by a profound and sustained increase in endogenous erythropoietin (EPO) and ultimately an augmented erythrocyte volume, while simultaneously allowing athletes to "train low" for the purpose of replicating sea-level training intensity and oxygen flux, thereby inducing beneficial metabolic and neuromuscular adaptations. In addition to "natural/terrestrial" LH+TL, several simulated LH+TL devices have been developed to conveniently bring the mountain to the athlete, including nitrogen apartments, hypoxic tents, and hypoxicator devices. One of the key questions regarding the practical application of LH+TL is, what is the optimal hypoxic dose needed to facilitate altitude acclimatization and produce the expected beneficial physiological responses and sea-level performance effects? The purpose of this paper is to objectively answer that question, on the basis of an extensive body of research by our group in LH+TL altitude training. We will address three key questions: 1) What is the optimal altitude at which to live? 2) How many days are required at altitude? and 3) How many hours per day are required? On the basis of consistent findings from our research group, we recommend that for athletes to derive the physiological benefits of LH+TL, they need to live at a natural elevation of 2000-2500 m for >or=4 wk for >or=22 h.d(-1). PMID:17805093

  7. Effects of Acute and Chronic Heavy Metal (Cu, Cd, and Zn) Exposure on Sea Cucumbers (Apostichopus japonicus).

    PubMed

    Li, Li; Tian, Xiangli; Yu, Xiao; Dong, Shuanglin

    2016-01-01

    Acute and chronic toxicity tests were conducted with sea cucumber (Apostichopus japonicus) exposed to heavy metals. Acute toxicity values (96 h LC50) were 2.697, 0.133, and 1.574 mg L(-1) for Zn, Cu, and Cd, respectively, and were ranked in order of toxicity: Cu > Cd > Zn. Under chronic metal exposure the specific growth rates of sea cucumbers decreased with the increase of metal concentration for all the three metals. After acute metal exposure, the oxygen consumption rate (OCR) decreased. The OCRs in all groups were significantly different than control (P < 0.05) except in the group treated with 1.00 mg L(-1) Zn (P < 0.05), where the increase of OCR was observed. The OCRs in groups chronically exposed to metals were significantly lower than that in the control group (P < 0.05). The activity of both pyruvate kinase (PK) and hexokinase (HK) in sea cucumbers followed: respiratory tree > muscle > intestine in natural sea water. After chronic Zn, Cu, and Cd exposure, the change pattern of HK and PK in respiratory tree, muscle, and intestine varied slightly. However, the activity of the enzyme showed a general trend of increase and then decrease and the higher the exposure concentration was, the earlier the highest point of enzyme activity was obtained. PMID:27382568

  8. Effects of Acute and Chronic Heavy Metal (Cu, Cd, and Zn) Exposure on Sea Cucumbers (Apostichopus japonicus)

    PubMed Central

    Li, Li; Tian, Xiangli; Yu, Xiao; Dong, Shuanglin

    2016-01-01

    Acute and chronic toxicity tests were conducted with sea cucumber (Apostichopus japonicus) exposed to heavy metals. Acute toxicity values (96 h LC50) were 2.697, 0.133, and 1.574 mg L−1 for Zn, Cu, and Cd, respectively, and were ranked in order of toxicity: Cu > Cd > Zn. Under chronic metal exposure the specific growth rates of sea cucumbers decreased with the increase of metal concentration for all the three metals. After acute metal exposure, the oxygen consumption rate (OCR) decreased. The OCRs in all groups were significantly different than control (P < 0.05) except in the group treated with 1.00 mg L−1 Zn (P < 0.05), where the increase of OCR was observed. The OCRs in groups chronically exposed to metals were significantly lower than that in the control group (P < 0.05). The activity of both pyruvate kinase (PK) and hexokinase (HK) in sea cucumbers followed: respiratory tree > muscle > intestine in natural sea water. After chronic Zn, Cu, and Cd exposure, the change pattern of HK and PK in respiratory tree, muscle, and intestine varied slightly. However, the activity of the enzyme showed a general trend of increase and then decrease and the higher the exposure concentration was, the earlier the highest point of enzyme activity was obtained. PMID:27382568

  9. Effects of water depth and substrate color on the growth and body color of the red sea cucumber, Apostichopus japonicus

    NASA Astrophysics Data System (ADS)

    Jiang, Senhao; Dong, Shuanglin; Gao, Qinfeng; Ren, Yichao; Wang, Fang

    2015-05-01

    Three color variants of the sea cucumber, Apostichopus japonicus are recognized, the red one is highly valued in the market. When the red variant is cultured in ponds in China, its body color changes from red to celadon in 3-6 months. The effects of water depth and substrate color on the growth and body color of this animal were investigated. Juveniles of red A. japonicus were cultured in cages suspended at a range of water depths (20, 50, 100, 150 and 200 cm). The specific growth rate of red sea cucumbers was significantly higher in animals cultured at deeper water layers compared with those grown at shallowers. Body weights were greatest for sea cucumbers cultured at a depth of 150 cm and their survival rates were highest at a depth of 200 cm. A scale to evaluate the color of red sea cucumbers ( R value) was developed using a Pantone standard color card. All stocked animals in the 9-month trial retained a red color, however the red body color was much more intense in sea cucumbers cultured at shallower depths, while animals suspended in deeper layers became pale. In a separate trial, A. japonicus were cultured in suspended cages with seven different colored substrates. Substrate color had a significant effect on the growth and body-color of red A. japonicus. The yield were greatest for A. japonicus cultured on a yellow substrate, followed by green > white > orange > red > black and blue. All sea cucumbers in the 7-month trial retained a red color, although the red was most intense (highest R value) in animals cultured on a blue substrate and pale (lowest R value) for animals cultured on a green substrate.

  10. Effects of dietary nucleotides on growth, non-specific immune response and disease resistance of sea cucumber Apostichopus japonicas.

    PubMed

    Wei, Zehong; Yi, Lina; Xu, Wei; Zhou, Huihui; Zhang, Yanjiao; Zhang, Wenbing; Mai, Kangsen

    2015-11-01

    A 9-week feeding trial was conducted to investigate the effects of dietary nucleotides (NT) on growth, immune response and disease resistance of sea cucumber Apostichopus japonicas (initial weight: 5.87 ± 0.03 g). Four graded levels of dietary NT were designed as 0, 150, 375 and 700 mg/kg, respectively. After the feeding trial, sea cucumbers were challenged with Vibrio splendidus for the determination of disease resistance. The results showed that the specific growth rates were significantly higher in sea cucumber fed the diet with 375 mg/kg NT than those fed the basal diet without NT supplementation (P < 0.05). The highest total coelomocytes counts in coelomic fluid were found in the treatment with 150 mg/kg of dietary NT (P < 0.05). Compared to those fed with the basal diet, sea cucumber fed diets with nucleotides (≥ 375 mg/kg) had significantly higher phagocytic activities in coelomic fluid (P < 0.05). Respiratory burst activities in coelomic fluid significantly increased with increasing dietary NT supplementations up to 700 mg/kg (P < 0.05). No significant differences in the activities of superoxide dismutase, total nitric oxide synthase and acid phosphatase in coelomic fluid were found among all the treatments (P > 0.05). After being challenged with V. splendidus, the cumulative mortalities of sea cucumber fed diets with 150 and 375 mg/kg NT were significantly lower than that in the treatment without dietary nucleotide supplementation (P < 0.05). Under the experimental conditions, the present results confirmed that a diet supplemented with 375 mg/kg NT is able to enhance both non-specific immune response and growth of sea cucumber in vivo. In conclusion, it was showed that dietary NT does increase the growth performance, non-specific immunity and disease resistance of sea cucumber. The optimum dietary NT supplementation level for sea cucumber was found to be 375 mg/kg. The application of dietary NT may present a novel strategy for health management in

  11. Effects of Salinity and Sea Level Change on Permafrost-Hosted Methane Hydrate Reservoirs

    NASA Astrophysics Data System (ADS)

    Elwood-Madden, M.

    2010-12-01

    Recent observations of methane release from sediments on the circum-arctic continental shelf indicate that arctic warming is likely leading to increased fluxes of methane . Thermodynamics predicts that 2-4 degree increases in global temperature will lead to massive marine hydrate decomposition; however, the rate of warming deep ocean waters and sediments is fairly slow, resulting in modest fluxes of methane over hundreds to thousands of years. In contrast, increasing arctic temperatures and rising sea level may have immediate effects on permafrost-hosted hydrate deposits. Rising sea level affects both the geothermal gradient of the region and the salinity of pore waters, leading to hydrate destabilization (Figure 1). Seawater infiltration of permafrost may be currently dissociating permafrost-hosted methane hydrate through a combination of mechanisms: shifting geothermal gradients to higher temperatures, addition of salts due to seawater encroachment, and the transition from solid state diffusion of methane through overlying ice cemented permafrost to mass transfer through seawater-saturated sediments via aqueous diffusion, advection, or ebullition. Effects of seawater erosion of permafrost have been observed in arctic coastal areas, and degradation of arctic permafrost is predicted to continue, especially in coastal areas. However, the rate at which these processes proceed and their effects on permafrost-hosted methane hydrates have been largely uninvestigated. Changes in geothermal gradient alone take hundreds to thousands of years to affect relatively deep hydrate reservoirs. However, warmer temperatures combined with freezing point depression effects of seawater may lead to rapid melting of permafrost ice, thus accelerating the transfer of heat to the hydrate reservoirs and changing the mass transfer mechanism of methane release from slow solid state diffusion through ice to more rapid aqueous diffusion, advection, or ebullition. Therefore, we hypothesize that

  12. New insights into negative effects of lithium on sea urchin Paracentrotus lividus embryos

    NASA Astrophysics Data System (ADS)

    Ruocco, Nadia; Costantini, Maria; Santella, Luigia

    2016-08-01

    The diffuse use of lithium in a number of industrial processes has produced a significant contamination of groundwater and surface water with it. The increased use of lithium has generated only scarce studies on its concentrations in ambient waters and on its effects on aquatic organisms. Only few contributions have focused on the toxicity of lithium in marine organisms (such as marine animals, algae and vegetables), showing that the toxic effect depends on the animal species. In the present study we describe the morphological and the molecular effects of lithium chloride (LiCl), using the sea urchin Paracentrotus lividus as a model organism. We show that LiCl, if added to the eggs before fertilization, induces malformations in the embryos in a dose-dependent manner. We have also followed by RT qPCR the expression levels of thirty seven genes (belonging to different classes of functional processes, such as stress, development, differentiation, skeletogenesis and detoxifications) to identify the molecular targets of LiCl. This study opens new perspectives for the understanding of the mechanism of action of lithium on marine organisms. The findings may also have relevance outside the world of marine organisms since lithium is widely prescribed for the treatment of human bipolar disorders.

  13. Consequences of detergent pollution of the sea: effects on regenerating sponge cubes of Geodia cydonium.

    PubMed

    Zahn, R K; Zahn, G; Müller, W E; Müller, I; Beyer, R; Müller-Berger, U; Kupelec, B; Rijavec, M; Britvić, S

    1977-09-01

    Regenerating cubes of the sponge Geodia cydonium cyconium were used as a model in the investigation of detergent pollution in the sea. The anionic detergent sodium dodecylsulphate (SDS) and a 1:1 mixture of Faks and Radion, two commercial laundry detergents, were used in the concentration range from 1 X 10(-9) g/ml (1 ppb) to 1 X 10(-5) g/ml. It is shown that SDS is taken up, weakly accumulated but not incorporated into the macromolecular fractions of the sponge. At concentrations of 0.1 ppm and above, SDS decreases the uptake of thymidine, uridine and phenylalanine into the acid-soluble sponge fraction. Their incorporation into the acid insoluble fractions, which have been isolated, was different from the controls at 10 ppb and higher levels. Faks and Radion were less active by a factor of 10. However, they showed similar effects. The chemical composition of the regenerating sponge cubes with respect to DNA, RNA and protein content has been evaluated. The alterations are less pronounced on detergent incubation than precursor uptake. The use of the cetyltrimethyl-ammoniumbromide-turbidity-dilution technique reveals drastic qualitative changes in the nucleic acid fractions. The relevant literature on biological effects of detergent is listed. It is shown that this investigation extends the scale of known effects far into the low and pollution-relevant concentration levels.

  14. New insights into negative effects of lithium on sea urchin Paracentrotus lividus embryos.

    PubMed

    Ruocco, Nadia; Costantini, Maria; Santella, Luigia

    2016-01-01

    The diffuse use of lithium in a number of industrial processes has produced a significant contamination of groundwater and surface water with it. The increased use of lithium has generated only scarce studies on its concentrations in ambient waters and on its effects on aquatic organisms. Only few contributions have focused on the toxicity of lithium in marine organisms (such as marine animals, algae and vegetables), showing that the toxic effect depends on the animal species. In the present study we describe the morphological and the molecular effects of lithium chloride (LiCl), using the sea urchin Paracentrotus lividus as a model organism. We show that LiCl, if added to the eggs before fertilization, induces malformations in the embryos in a dose-dependent manner. We have also followed by RT qPCR the expression levels of thirty seven genes (belonging to different classes of functional processes, such as stress, development, differentiation, skeletogenesis and detoxifications) to identify the molecular targets of LiCl. This study opens new perspectives for the understanding of the mechanism of action of lithium on marine organisms. The findings may also have relevance outside the world of marine organisms since lithium is widely prescribed for the treatment of human bipolar disorders.

  15. New insights into negative effects of lithium on sea urchin Paracentrotus lividus embryos.

    PubMed

    Ruocco, Nadia; Costantini, Maria; Santella, Luigia

    2016-01-01

    The diffuse use of lithium in a number of industrial processes has produced a significant contamination of groundwater and surface water with it. The increased use of lithium has generated only scarce studies on its concentrations in ambient waters and on its effects on aquatic organisms. Only few contributions have focused on the toxicity of lithium in marine organisms (such as marine animals, algae and vegetables), showing that the toxic effect depends on the animal species. In the present study we describe the morphological and the molecular effects of lithium chloride (LiCl), using the sea urchin Paracentrotus lividus as a model organism. We show that LiCl, if added to the eggs before fertilization, induces malformations in the embryos in a dose-dependent manner. We have also followed by RT qPCR the expression levels of thirty seven genes (belonging to different classes of functional processes, such as stress, development, differentiation, skeletogenesis and detoxifications) to identify the molecular targets of LiCl. This study opens new perspectives for the understanding of the mechanism of action of lithium on marine organisms. The findings may also have relevance outside the world of marine organisms since lithium is widely prescribed for the treatment of human bipolar disorders. PMID:27562248

  16. New insights into negative effects of lithium on sea urchin Paracentrotus lividus embryos

    PubMed Central

    Ruocco, Nadia; Costantini, Maria; Santella, Luigia

    2016-01-01

    The diffuse use of lithium in a number of industrial processes has produced a significant contamination of groundwater and surface water with it. The increased use of lithium has generated only scarce studies on its concentrations in ambient waters and on its effects on aquatic organisms. Only few contributions have focused on the toxicity of lithium in marine organisms (such as marine animals, algae and vegetables), showing that the toxic effect depends on the animal species. In the present study we describe the morphological and the molecular effects of lithium chloride (LiCl), using the sea urchin Paracentrotus lividus as a model organism. We show that LiCl, if added to the eggs before fertilization, induces malformations in the embryos in a dose-dependent manner. We have also followed by RT qPCR the expression levels of thirty seven genes (belonging to different classes of functional processes, such as stress, development, differentiation, skeletogenesis and detoxifications) to identify the molecular targets of LiCl. This study opens new perspectives for the understanding of the mechanism of action of lithium on marine organisms. The findings may also have relevance outside the world of marine organisms since lithium is widely prescribed for the treatment of human bipolar disorders. PMID:27562248

  17. Effects of sample storage and shell orientation on LA-ICPMS trace element measurements on deep-sea mussels.

    PubMed

    Génio, Luciana; Simon, Klaus; Kiel, Steffen; Cunha, Marina R

    2015-12-08

    Geochemical markers are being increasingly applied to fundamental questions in population and community ecology in marine habitats because they allow inferences on individuals dispersal, but vital effects, small sample size and instrumental limitation are still challenging particularly in deep-sea studies. Here we use shells of the deep-sea bivalve Idas modiolaeformis to assess potential effects of sample storage, mineralogy, and valve orientation on LA-ICPMS measurements. Trace element concentrations of (24)Mg, (43)Ca, (88)Sr, (137)Ba, (208)Pb, and (238)U are not affected by the two most commonly used storage methods of biologic deep-sea samples (frozen at -20°C and fixed in 95% ethanol); thus combined analysis of differently preserved specimens is possible when the number of individuals is insufficient and distinct sample fixation is needed for multiple purposes. Valve orientation had a strong impact on quantification of trace elements in the calcitic but not in the aragonitic layer of adult shells. Hence, to enable comparisons between adult shells and entirely aragonitic embryonic shells, a reference map of site-specific signatures can potentially be generated using the aragonitic layer of the adult shells. Understanding ontogenetic changes and environmental effects in trace element incorporation is critical before geochemical fingerprinting can be used as a tool for larval dispersal studies in the deep-sea.

  18. Combined effect of glycine and sea salt on aerosol cloud droplet activation predicted by molecular dynamics simulations.

    PubMed

    Sun, Lu; Hede, Thomas; Tu, Yaoquan; Leck, Caroline; Agren, Hans

    2013-10-17

    The present study illustrates the combined effect of organic and inorganic compounds on cloud droplet nucleation and activation processes representative for the marine environment. Amino acids and sea salt are common marine cloud condensation nuclei (CCN) which act as a prerequisite for growth of cloud droplets. The chemical and physical properties of these CCN play a key role for interfacial properties such as surface tension, which is important for the optical properties of clouds and for heterogeneous reactions. However, there is a lack of detailed information and in situ measurements of surface tension of such nanosized droplets. Here we present a study of the combined effect of zwitterionic glycine (ZGLY) and sea salt in nanosized water droplets using molecular dynamics simulations, where particular emphasis is placed on the surface tension for the nanosized droplets. The critical supersaturation is estimated by the Köhler equation. It is found that dissolved sea salt interacts with ZGLY through a water bridge and weakens the hydrogen bonds among ZGLYs, which has a significant effect on both surface tension and water vapor supersaturation. Clusters of glycine mixed with sea salt deliquesce more efficiently and have higher growth factors. PMID:24063576

  19. Combined effect of glycine and sea salt on aerosol cloud droplet activation predicted by molecular dynamics simulations.

    PubMed

    Sun, Lu; Hede, Thomas; Tu, Yaoquan; Leck, Caroline; Agren, Hans

    2013-10-17

    The present study illustrates the combined effect of organic and inorganic compounds on cloud droplet nucleation and activation processes representative for the marine environment. Amino acids and sea salt are common marine cloud condensation nuclei (CCN) which act as a prerequisite for growth of cloud droplets. The chemical and physical properties of these CCN play a key role for interfacial properties such as surface tension, which is important for the optical properties of clouds and for heterogeneous reactions. However, there is a lack of detailed information and in situ measurements of surface tension of such nanosized droplets. Here we present a study of the combined effect of zwitterionic glycine (ZGLY) and sea salt in nanosized water droplets using molecular dynamics simulations, where particular emphasis is placed on the surface tension for the nanosized droplets. The critical supersaturation is estimated by the Köhler equation. It is found that dissolved sea salt interacts with ZGLY through a water bridge and weakens the hydrogen bonds among ZGLYs, which has a significant effect on both surface tension and water vapor supersaturation. Clusters of glycine mixed with sea salt deliquesce more efficiently and have higher growth factors.

  20. Effects of sample storage and shell orientation on LA-ICPMS trace element measurements on deep-sea mussels

    PubMed Central

    Génio, Luciana; Simon, Klaus; Kiel, Steffen; Cunha, Marina R.

    2015-01-01

    Geochemical markers are being increasingly applied to fundamental questions in population and community ecology in marine habitats because they allow inferences on individuals dispersal, but vital effects, small sample size and instrumental limitation are still challenging particularly in deep-sea studies. Here we use shells of the deep-sea bivalve Idas modiolaeformis to assess potential effects of sample storage, mineralogy, and valve orientation on LA-ICPMS measurements. Trace element concentrations of 24Mg, 43Ca, 88Sr, 137Ba, 208Pb, and 238U are not affected by the two most commonly used storage methods of biologic deep-sea samples (frozen at –20°C and fixed in 95% ethanol); thus combined analysis of differently preserved specimens is possible when the number of individuals is insufficient and distinct sample fixation is needed for multiple purposes. Valve orientation had a strong impact on quantification of trace elements in the calcitic but not in the aragonitic layer of adult shells. Hence, to enable comparisons between adult shells and entirely aragonitic embryonic shells, a reference map of site-specific signatures can potentially be generated using the aragonitic layer of the adult shells. Understanding ontogenetic changes and environmental effects in trace element incorporation is critical before geochemical fingerprinting can be used as a tool for larval dispersal studies in the deep-sea. PMID:26643064

  1. Effect of hypoxia on benthic nutrient fluxes in the northwestern Black Sea

    NASA Astrophysics Data System (ADS)

    Friedrich, J.

    2012-04-01

    The western Black Sea shelf has been affected by eutrophication from the 1960s to the mid 1990s. A combination of increased nutrient loads from the major inflowing rivers Danube, Dniester and Dnepr and favourable climate conditions led to high productivity regimes. As a consequence, increased oxygen consumption due to decomposition of organic matter caused recurrent seasonal bottom water hypoxia for more than 20 years. In addition, recycling of nutrients from organic matter settling to the seafloor along with tight benthic-pelagic coupling represents an important internal source for productivity, hence internally supporting eutrophication. From the 1970s to 1990s, the benthic and pelagic systems deteriorated and ecosystem structure and functioning changed. Following the collapse of the centrally planned economies in the eastern European countries during the 1990s, the riverine nutrient input decreased, and the ecosystem, now slowly responding, shows signs of recovery; e.g. by a decrease in hypoxic events. In this study, benthic nutrient flux data from in-situ and ex-situ experiments during the 1990s on the Danube-influenced north-western Black Sea shelf and data from the 2000s, including the EU-FP7 HYPOX experiments, are analysed to reveal the effect of hypoxia on benthic nutrient fluxes. Mann-Whitney statistical tests have been applied to demonstrate the significance of differences in fluxes due to varying oxygen conditions in the water. During the 1990s experiments, bottom water hypoxia was encountered in all locations, while during the 2000s hypoxia has been met only during summer in the Danube Prodelta area and near the Dniester mouth. Indeed, bottom water oxygen in the 1990s has been statistically significantly lower than in the 2000s while benthic oxygen consumption was higher during eutrophication-induced hypoxia. The benthic nutrient fluxes in the 1990s and the 2000s however do not differ significantly. During hypoxia, despite ceasing eutrophication

  2. The effects of resolving the Canadian Arctic Archipelago in a finite element sea ice model

    NASA Astrophysics Data System (ADS)

    Lietaer, Olivier; Fichefet, Thierry; Legat, Vincent

    Though narrow straits may have a strong influence on the large-scale sea ice mass balance, they are often crudely represented in coarse resolution sea ice models. Unstructured meshes, with their natural ability to fit boundaries and locally increase the mesh resolution, propose an alternative framework to capture the complex oceanic areas formed by coasts and islands. In this paper, we develop a finite element sea ice model to investigate the sensitivity of the Arctic sea ice cover features to the resolution of the narrow straits constituting the Canadian Arctic Archipelago. The model is a two-level dynamic-thermodynamic sea ice model, including a viscous-plastic rheology. It is run over 1979-2005, forced by daily NCEP/NCAR reanalysis data. Confronting qualitatively numerical experiments with observations shows a good agreement with satellite and buoys measurements. Due to its simple representation of the oceanic interactions, the model overestimates the sea ice extent during winter in the southernmost parts of the Arctic, while the Baffin Bay and Kara Sea remain ice-covered during summer. In order to isolate the benefits from resolving the Canadian Arctic Archipelago, a numerical experiment is performed where we artificially close the archipelago. Focusing on the large-scale sea ice thickness pattern, no significant change is found in our model, except in the close surroundings of the archipelago. However, the local and short-term influences of the ice exchanges are nonnegligible. In particular, we show that the ice volume associated to the Canadian Arctic Archipelago represents 10% of the Northern Hemisphere sea ice volume and that the annual mean ice export towards Baffin Bay amounts to 125 km 3 yr -1, which may play an important role on the convective overturning in the Labrador Sea.

  3. 2 CFR 25.205 - Effect of noncompliance with a requirement to obtain a DUNS number or register in the CCR.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 2 Grants and Agreements 1 2014-01-01 2014-01-01 false Effect of noncompliance with a requirement to obtain a DUNS number or register in the CCR. 25.205 Section 25.205 Grants and Agreements Office of Management and Budget Guidance for Grants and Agreements OFFICE OF MANAGEMENT AND BUDGET GOVERNMENTWIDE GUIDANCE FOR GRANTS AND AGREEMENTS...

  4. The Effect of Novel Research Activities on Long-term Survival of Temporarily Captive Steller Sea Lions (Eumetopias jubatus).

    PubMed

    Shuert, Courtney; Horning, Markus; Mellish, Jo-Ann

    2015-01-01

    Two novel research approaches were developed to facilitate controlled access to, and long-term monitoring of, juvenile Steller sea lions for periods longer than typically afforded by traditional fieldwork. The Transient Juvenile Steller sea lion Project at the Alaska SeaLife Center facilitated nutritional, physiological, and behavioral studies on the platform of temporary captivity. Temporarily captive sea lions (TJs, n = 35) were studied, and were intraperitoneally implanted with Life History Transmitters (LHX tags) to determine causes of mortality post-release. Our goal was to evaluate the potential for long-term impacts of temporary captivity and telemetry implants on the survival of study individuals. A simple open-population Cormack-Jolly-Seber mark-recapture model was built in program MARK, incorporating resightings of uniquely branded study individuals gathered by several contributing institutions. A priori models were developed to weigh the evidence of effects of experimental treatment on survival with covariates of sex, age, capture age, cohort, and age class. We compared survival of experimental treatment to a control group of n = 27 free-ranging animals (FRs) that were sampled during capture events and immediately released. Sex has previously been show to differentially affect juvenile survival in Steller sea lions. Therefore, sex was included in all models to account for unbalanced sex ratios within the experimental group. Considerable support was identified for the effects of sex, accounting for over 71% of total weight for all a priori models with delta AICc <5, and over 91% of model weight after removal of pretending variables. Overall, most support was found for the most parsimonious model based on sex and excluding experimental treatment. Models including experimental treatment were not supported after post-hoc considerations of model selection criteria. However, given the limited sample size, alternate models including effects of experimental

  5. The Effect of Novel Research Activities on Long-term Survival of Temporarily Captive Steller Sea Lions (Eumetopias jubatus)

    PubMed Central

    Shuert, Courtney; Horning, Markus; Mellish, Jo-Ann

    2015-01-01

    Two novel research approaches were developed to facilitate controlled access to, and long-term monitoring of, juvenile Steller sea lions for periods longer than typically afforded by traditional fieldwork. The Transient Juvenile Steller sea lion Project at the Alaska SeaLife Center facilitated nutritional, physiological, and behavioral studies on the platform of temporary captivity. Temporarily captive sea lions (TJs, n = 35) were studied, and were intraperitoneally implanted with Life History Transmitters (LHX tags) to determine causes of mortality post-release. Our goal was to evaluate the potential for long-term impacts of temporary captivity and telemetry implants on the survival of study individuals. A simple open-population Cormack-Jolly-Seber mark-recapture model was built in program MARK, incorporating resightings of uniquely branded study individuals gathered by several contributing institutions. A priori models were developed to weigh the evidence of effects of experimental treatment on survival with covariates of sex, age, capture age, cohort, and age class. We compared survival of experimental treatment to a control group of n = 27 free-ranging animals (FRs) that were sampled during capture events and immediately released. Sex has previously been show to differentially affect juvenile survival in Steller sea lions. Therefore, sex was included in all models to account for unbalanced sex ratios within the experimental group. Considerable support was identified for the effects of sex, accounting for over 71% of total weight for all a priori models with delta AICc <5, and over 91% of model weight after removal of pretending variables. Overall, most support was found for the most parsimonious model based on sex and excluding experimental treatment. Models including experimental treatment were not supported after post-hoc considerations of model selection criteria. However, given the limited sample size, alternate models including effects of experimental

  6. The Effect of Novel Research Activities on Long-term Survival of Temporarily Captive Steller Sea Lions (Eumetopias jubatus).

    PubMed

    Shuert, Courtney; Horning, Markus; Mellish, Jo-Ann

    2015-01-01

    Two novel research approaches were developed to facilitate controlled access to, and long-term monitoring of, juvenile Steller sea lions for periods longer than typically afforded by traditional fieldwork. The Transient Juvenile Steller sea lion Project at the Alaska SeaLife Center facilitated nutritional, physiological, and behavioral studies on the platform of temporary captivity. Temporarily captive sea lions (TJs, n = 35) were studied, and were intraperitoneally implanted with Life History Transmitters (LHX tags) to determine causes of mortality post-release. Our goal was to evaluate the potential for long-term impacts of temporary captivity and telemetry implants on the survival of study individuals. A simple open-population Cormack-Jolly-Seber mark-recapture model was built in program MARK, incorporating resightings of uniquely branded study individuals gathered by several contributing institutions. A priori models were developed to weigh the evidence of effects of experimental treatment on survival with covariates of sex, age, capture age, cohort, and age class. We compared survival of experimental treatment to a control group of n = 27 free-ranging animals (FRs) that were sampled during capture events and immediately released. Sex has previously been show to differentially affect juvenile survival in Steller sea lions. Therefore, sex was included in all models to account for unbalanced sex ratios within the experimental group. Considerable support was identified for the effects of sex, accounting for over 71% of total weight for all a priori models with delta AICc <5, and over 91% of model weight after removal of pretending variables. Overall, most support was found for the most parsimonious model based on sex and excluding experimental treatment. Models including experimental treatment were not supported after post-hoc considerations of model selection criteria. However, given the limited sample size, alternate models including effects of experimental

  7. Air pollutant transport in a coastal environment. Part 1: Two-dimensional simulations of sea-breeze and mountain effects

    NASA Technical Reports Server (NTRS)

    Lu, Rong; Turco, Richard P.

    1994-01-01

    Over the southern California coastal region, observations of the vertical distributions of pollutants show that maximum concentrations can occur within temperature inversion layers well above the surface. A mesoscale model is used to study the dynamical phenomena that cause such layers, including sea breezes and mountain flows, and to study the characteristics of air pollutant transport in a coastal environment capped by a temperature inversion. The mathematical and physical structure of the model is described. Two-dimensional simulations corresponding to four configurations of coastal plains and mountains are discussed. The simulations reveal that pollutant transport over a coastal plain is strongly influenced by the topographic configuration, including the height of coastal mountains and their distance from the coastline. Sea breezes induced by land-sea thermal contrasts, as well as upslope winds induced along mountain flanks, both create vertical transport that can lead to the formation of elevated pollution layers. The sea-breeze circulation generates pollution layers by undercutting the mixed layer and lofting pollutants into the stable layer. Heating of mountain slopes acts to vent pollutants above the mountain ridge during the day; during the evening, pollutants can be injected directly into the inversion layer from the decaying upslope flows. In a land-sea configuration with mountains close to the coastline, the sea breeze and heated-mountain flow are strongly coupled. In the afternoon, this interaction can produce upslope flow from which polluted air is detrained into the inversion layer as a return circulation. When the mountains lie farther inland, however, pollutants may be trapped aloft when the mixed layer stabilizes in the late afternoon. As the nocturnal boundary layer forms over the coast in the evening, polluted mixed-layer air is effectively left behind in the inversion layer. In the Los Angeles Basin, the formation mechanism for elevated

  8. Attenuated Effects of Deep-Sea Water on Hepatic Apoptosis in STZ-Induced Diabetic Rats.

    PubMed

    Hsu, Tsai-Ching; Chiu, Chun-Ching; Lin, Hsou-Lin; Kao, Tseng-Wei; Chen, Li-Jeng; Wu, Li-Yi; Huang, Chih-Yang; Tzang, Bor-Show

    2015-06-30

    Diabetes mellitus (DM) is a metabolic disorder and increasing evidences have indicated a connection between DM and hepatic abnormality. Deep-sea water (DSW) has been applied in many fields, especially in medicine; herein, we investigated the influence of DSW on hepatic apoptosis in streptozocin (STZ)-induced diabetes rats. Our experimental results firstly demonstrated the beneficial effects of 1×DSW, 2×DSW and 3×DSW in alleviating hepatic apoptosis in STZ-induced diabetic rats. We demonstrated that 1×DSW, 2×DSW and 3×DSW significantly suppressed the caspase-3 activity and TUNEL-positive cells in livers of STZ-induced diabetic rats. Significant reductions of both Fas-dependent and mitochondrial-dependent apoptotic molecules were also detected in livers of STZ-induced diabetic rats receiving DSW. Additionally, apoptotic signaling molecules such as phosphorylated IκB-α and NF-κB were significantly reduced in livers of DSW-treated STZ-induced diabetic rats. These findings indicate hepatic protective effects of DSW on DM and suggest DSW as a possible ingredient for health food. PMID:26014125

  9. Screen and effect analysis of immunostimulants for sea cucumber, Apostichopus japonicus

    NASA Astrophysics Data System (ADS)

    Li, Jiye; Sun, Xiuqin; Zheng, Fengrong; Hao, Linhua

    2009-02-01

    Immunostimulants may improve disease resistance of aquaculture animals by promoting the nonspecific immunity response of the organisms. Five types of saccharides, including chitosan, yeast polysaccharide, burdock oligosaccharide, seaweed polysaccharide and lentinus edodes polysaccharide, were screened for potential use as immunostimulants by using spectrophotometry. The saccharides were injected into Apostichopus japonicus, a sea cucumber, and the lysozyme and superoxide dismutase (SOD) activities of the coelomic fluid and epidermal slime were monitored in six consecutive days. The results show that the lysozyme activity of the animal’s coelomic fluid was significantly stimulated on day 2, day 4 and day 6 after the injection of the saccharides ( P<0.05). The effects of chitosan and yeast polysaccharide were the most notable. The lysozyme activity of the epidermal slime was significantly increased by chitosana, yeast polysaccharide, seaweed polysaccharide, and burdock oligosaccharide on day 1 and day 2 after the injection ( P<0.05). The SOD activity of the coelomic fluid was significantly promoted by the saccharides on day 2 and day 4 post-injection ( P<0.05), while the SOD activity of the epidermal slime increased on day 2. These findings indicate that chitosan and yeast polysaccharide are the most effective immunostimulants and potential healthy anti-disease feedstuff for A. japonicus.

  10. Sea surface height evidence for long-term warming effects of tropical cyclones on the ocean.

    PubMed

    Mei, Wei; Primeau, François; McWilliams, James C; Pasquero, Claudia

    2013-09-17

    Tropical cyclones have been hypothesized to influence climate by pumping heat into the ocean, but a direct measure of this warming effect is still lacking. We quantified cyclone-induced ocean warming by directly monitoring the thermal expansion of water in the wake of cyclones, using satellite-based sea surface height data that provide a unique way of tracking the changes in ocean heat content on seasonal and longer timescales. We find that the long-term effect of cyclones is to warm the ocean at a rate of 0.32 ± 0.15 PW between 1993 and 2009, i.e., ∼23 times more efficiently per unit area than the background equatorial warming, making cyclones potentially important modulators of the climate by affecting heat transport in the ocean-atmosphere system. Furthermore, our analysis reveals that the rate of warming increases with cyclone intensity. This, together with a predicted shift in the distribution of cyclones toward higher intensities as climate warms, suggests the ocean will get even warmer, possibly leading to a positive feedback.

  11. In-situ burning - one method of effective oil spill response in the South China Sea

    SciTech Connect

    Boben, M.E.; Yanting, Yue

    1996-12-31

    Phillips Petroleum International Corporation Asia (PPICA) is the operator of the twin Xijiang Oilfields in the South China Sea. The very special characteristics of the Xijiang crude demanded that innovative means of cleanup be employed in the event of a major oil spill. The Xijiang crude has a very high wax content and high pour point. The crude must be heated to flow. In the event of a major oil spill, clean up would require non-traditional means of response. During the laboratory analysis it was discovered that if a specific thickness of crude could be contained on the surface of the water that it could be ignited and burned. The potential effectiveness of the burn was ascertained to be 95-98%. A decision was made in 1992 during the design engineering phase to utilize in-situ burning as the primary means of response in the event of a major oil spill. During April 1995 the first ever demonstration of in-situ burning was conducted in Shekou, Sheizhen, People`s Republic of China by Phillips Petroleum International Corporation Asia. This exercise clearly demonstrated the effectiveness of in-situ burning on the Xijiang crude.

  12. Effects of warm acclimation on physiology and gonad development in the sea urchin Evechinus chloroticus.

    PubMed

    Delorme, Natalí J; Sewell, Mary A

    2016-08-01

    The physiology of the New Zealand sea urchin Evechinus chloroticus was evaluated through feeding, respiration, growth and gonad growth in adult animals acclimated for 90days at 18°C (annual mean temperature) and 24°C (ambient summer temperature (21°C) +3°C). Measured parameters with representative rates of assimilation efficiency were used to calculate scope for growth (SfG) for each treatment. All physiological parameters were negatively affected at 24°C, showing a decrease in feeding rate which coincided with negative growth and gonad development at the end of the acclimation period, and a decrease in respiration rate suggesting metabolic depression. Histology of gonad samples after the acclimation period also showed no gametic material in animals acclimated at 24°C. All animals acclimated at 24°C had negative growth, differing from the calculated SfG which indicated that the animals had sufficient energy for production. The results suggest that calculated SfG in echinoderms should be used together with actual measurements of growth in individuals as, by itself, SfG may underestimate the actual effect of ocean warming when animals are exposed to stressful conditions. Overall, considering the total loss of reproductive output observed in E. chloroticus at higher temperatures, an increase in seawater temperature could dramatically influence the persistence of northern populations of this species, leading to flow-on effects in the subtidal ecosystem. PMID:27043875

  13. Attenuated Effects of Deep-Sea Water on Hepatic Apoptosis in STZ-Induced Diabetic Rats.

    PubMed

    Hsu, Tsai-Ching; Chiu, Chun-Ching; Lin, Hsou-Lin; Kao, Tseng-Wei; Chen, Li-Jeng; Wu, Li-Yi; Huang, Chih-Yang; Tzang, Bor-Show

    2015-06-30

    Diabetes mellitus (DM) is a metabolic disorder and increasing evidences have indicated a connection between DM and hepatic abnormality. Deep-sea water (DSW) has been applied in many fields, especially in medicine; herein, we investigated the influence of DSW on hepatic apoptosis in streptozocin (STZ)-induced diabetes rats. Our experimental results firstly demonstrated the beneficial effects of 1×DSW, 2×DSW and 3×DSW in alleviating hepatic apoptosis in STZ-induced diabetic rats. We demonstrated that 1×DSW, 2×DSW and 3×DSW significantly suppressed the caspase-3 activity and TUNEL-positive cells in livers of STZ-induced diabetic rats. Significant reductions of both Fas-dependent and mitochondrial-dependent apoptotic molecules were also detected in livers of STZ-induced diabetic rats receiving DSW. Additionally, apoptotic signaling molecules such as phosphorylated IκB-α and NF-κB were significantly reduced in livers of DSW-treated STZ-induced diabetic rats. These findings indicate hepatic protective effects of DSW on DM and suggest DSW as a possible ingredient for health food.

  14. Effects of the dynein inhibitor ciliobrevin on the flagellar motility of sea urchin spermatozoa.

    PubMed

    Wada, Yuuko; Baba, Shoji A; Kamimura, Shinji

    2015-04-01

    Ciliobrevin has recently been found to be a membrane-permeable inhibitor that is specific to AAA+ molecular motors such as cytoplasmic dyneins. In this study, we investigated how ciliobrevin inhibited the motility of sperm from sea urchins: Hemicentrotus pulcherrimus, Pseudocentrotus depressus, and Anthocidaris crassispina. After application of 100 μM of ciliobrevin A to live spermatozoa, swimming speed decreased gradually and flagellar motion stopped almost completely within 5 to 10 min. This inhibition was reversible and the frequency of flagellar beating was reduced in a concentration-dependent manner. Ciliobrevin had similar inhibitory effects on the flagellar beating of demembranated and reactivated sperm and the sliding disintegration of trypsin-treated axonemes. We also analyzed the curvature and shear angle of the beating flagella and found that the proximal region of the sperm flagellum was less sensitive to ciliobrevin compared with more distal regions, where bending motions were blocked completely. Interestingly, the shear angle analysis of flagellar motility showed that ciliobrevin induced highly asymmetric bends in the proximal region of the flagellum. These results suggest that there is heterogeneity in the inhibitory thresholds of dynein motors, which depend on the regions along the flagellar shaft (proximal or distal) and on the sites of doublets in the flagellar cross-section (doublet numbers). We expect that it will be possible to map the functional differences in dynein subtypes along and/or around the cross-sections of flagellar axonemes by analyzing the inhibitory effects of ciliobrevin.

  15. Effects of temperature, season and locality on wasting disease in the keystone predatory sea star Pisaster ochraceus.

    PubMed

    Bates, Amanda E; Hilton, Brett J; Harley, Christopher D G

    2009-11-01

    This study investigates wasting disease in the northeast Pacific keystone predatory sea star Pisaster ochraceus on the outer west coast of Vancouver Island (British Columbia, Canada). To quantify the effects of temperature, season and locality on the vulnerability of P. ochraceus to wasting disease, we conducted surveys and experiments in early and late summer. To test the prediction that a small increase in temperature would result in heightened infection intensities, we housed sea stars at different temperatures in the laboratory and caged sea stars subtidally at 2 depths. Prevalence and infection intensity were always higher in warm temperature treatments and did not differ between the sexes or with increasing size. Disease effects also varied with season and locality. Specimens held in aquaria displayed significantly higher disease prevalence and infection intensity in June versus August. Furthermore, sea stars from a sheltered inlet showed markedly higher prevalence of the disease in late summer, while wave-exposed sites had consistently low disease prevalence. Seasonal changes in reproductive potential, host condition and/or physiological acclimation, as well as differences in environmental regime among localities, may impact the dynamics of wasting disease. These results demonstrate that small increases in temperature could drive mass mortalities of Pisaster due to wasting disease, with vulnerability possibly reaching a peak in spring and in populations from sheltered localities. This is the most northern report of wasting disease in the class Asteroidea on the west coast of North America.

  16. Effect of co-culture of Chinese shrimp ( Fenneropenaeus chinensis) and sea cucumber ( Apostichopus japonicus Selenka) on pond environment

    NASA Astrophysics Data System (ADS)

    Yu, Haibo; Gao, Qinfeng; Dong, Shuanglin; Sun, Yongjun; Wang, Fang

    2016-10-01

    Monoculture of sea cucumber (pond S) and polyculture of shrimp with sea cucumber (pond SS) were established to evaluate the effect of shrimp on the environmental conditions of sea cucumber farming pond. Contributions of sediment organic matter (SOM2) resuspended from benthic sediment and the suspended particulate organic matter (SPOM) deposited from the water column to the precipitated organic matter (SOM1) collected with sediment traps were estimated with carbon stable isotope analysis. The results showed that the levels of SPOM and SOM2 in pond SS significantly decreased in comparison with those in pond S at the end of experiment ( P < 0.05), indicating that co-culturing shrimp in sea cucumber farming pond could purify the farming water. Carbon stable isotope analysis showed that the proportion of SOM2 in SOM1 in pond SS (84.97% ± 0.38%) was significantly lower than that in pond S (95.20% ± 0.30%) ( P < 0.05), suggesting that the resuspension of organic matter from benthic sediment into overlying water was reduced in polyculture pond. In contrast, the proportion of SPOM in SOM1 in pond SS (15.03% ± 0.38%) was significantly higher than that in pond S (4.80% ± 0.30%) ( P < 0.05), indicating that the sedimentation of SPOM from water column was enhanced in pond SS owing to the biodeposition effect of shrimp.

  17. Effects of environmental stress on intertidal mussels and their sea star predators.

    PubMed

    Petes, Laura E; Mouchka, Morgan E; Milston-Clements, Ruth H; Momoda, Tracey S; Menge, Bruce A

    2008-06-01

    Consumer stress models of ecological theory predict that predators are more susceptible to stress than their prey. Intertidal mussels, Mytilus californianus, span a vertical stress gradient from the low zone (lower stress) to the high zone (higher thermal and desiccation stress), while their sea star predators, Pisaster ochraceus, range from the low zone only into the lower edge of the mussel zone. In summer 2003, we tested the responses of sea stars and mussels to environmental stress in an experiment conducted on the Oregon coast. Mussels were transplanted from the middle of the mussel bed to cages in the low and high edges of the mussel bed. Sea star predators were added to half of the mussel cages. Mussels and sea stars were sampled between June and August for indicators of sublethal stress. Mussel growth was measured, and tissues were collected for heat shock protein (Hsp70) analyses and histological analyses of reproduction. Sea stars were weighed, and tissues were sampled for Hsp70 analyses. Mussels in high-edge cages had higher levels of total Hsp70 and exhibited spawning activity earlier in the summer than mussels in the low-edge cages. Sea stars suffered high mortality in the high edge, and low-edge sea stars lost weight but showed no differences in Hsp70 production. These results suggest that stress in the intertidal zone affected the mobile predator more than its sessile prey, which is consistent with predictions of consumer stress models.

  18. Effects of Sea Level-Rise on Carbon Accretion in Coastal Wetlands (Invited)

    NASA Astrophysics Data System (ADS)

    Morris, J. T.

    2010-12-01

    Long-term storage of organic carbon in sediment is one of the key functions of coastal wetlands. Owing to the rise of sea level, a fraction of their primary production is buried annually. However, the productivity of tidelands and, hence, carbon accretion depend on their relative elevation within the tidal frame. It has been shown empirically that there is an optimum relative elevation for maximum primary production. The equilibrium elevation is a function of the rate of sea-level rise. Hence, productivity and carbon accretion are also affected by the rate of sea-level rise. Mathematically it can be shown that tidelands maintain their elevation relative to the ocean through feedbacks among primary production, flooding, and sedimentation. At the low end of the sea-level-rise spectrum, a rising sea increases the flooding of marshes, decreasing sediment salinity, stimulating primary production and increasing sedimentation. At the high end, marshes cannot keep pace with sea level and convert to tidal mud flats or open water. Consequently, the long-term storage of carbon by tidelands will depend on the future trajectory of sea-level. In general, cumulative carbon accretion of existing marshes decreases as the forecasted rise in sea level increases. Other important variables include tide range and concentration of suspended sediments. Carbon accretion will be lower in microtidal than macrotidal estuaries, particularly at high rates of sea-level rise. Sensitivity of carbon accretion to tide range decreases as the concentration of suspended sediments increases. These results indicate that future carbon accretion by coastal wetlands will not be uniform in space or time.

  19. The effect of changing sea ice on the physical vulnerability of Arctic coasts

    NASA Astrophysics Data System (ADS)

    Barnhart, K. R.; Overeem, I.; Anderson, R. S.

    2014-09-01

    Sea ice limits the interaction of the land and ocean water in the Arctic winter and influences this interaction in the summer by governing the fetch. In many parts of the Arctic, the open-water season is increasing in duration and summertime sea-ice extents are decreasing. Sea ice provides a first-order control on the physical vulnerability of Arctic coasts to erosion, inundation, and damage to settlements and infrastructures by ocean water. We ask how the changing sea-ice cover has influenced coastal erosion over the satellite record. First, we present a pan-Arctic analysis of satellite-based sea-ice concentration specifically along the Arctic coasts. The median length of the 2012 open-water season, in comparison to 1979, expanded by between 1.5 and 3-fold by Arctic Sea sector, which allows for open water during the stormy Arctic fall. Second, we present a case study of Drew Point, Alaska, a site on the Beaufort Sea, characterized by ice-rich permafrost and rapid coastal-erosion rates, where both the duration of the open-water season and distance to the sea-ice edge, particularly towards the northwest, have increased. At Drew Point, winds from the northwest result in increased water levels at the coast and control the process of submarine notch incision, the rate-limiting step of coastal retreat. When open-water conditions exist, the distance to the sea ice edge exerts control on the water level and wave field through its control on fetch. We find that the extreme values of water-level setup have increased consistently with increasing fetch.

  20. Sea spray effects on soluble gases in the marine boundary layer

    SciTech Connect

    Soerensen, L.L.; Geernaert, G.L.

    1994-12-31

    The air-sea exchange of trace gases plays an integral role in coastal biogeochemistry, ecosystem dynamics, aerosol generation, cloud microphysics, air quality, and climate. To account for the gases which interact with the coastal sea, measurement techniques must be employed to sample highly variable environmental conditions, often with strong horizontal, vertical, and temporal gradients. The subsequent parameterizations serve as the basis for developing operational models, and assessing the impact of man`s activities on the environment. In this paper, the authors examine the role of sea spray on gas transfer by considering nitrogen compounds.

  1. Dynamics of sand ridges in coastal seas: the effect of storms, tides and grain sorting

    NASA Astrophysics Data System (ADS)

    Walgreen, M.

    2003-10-01

    The work presented in this thesis concerns the dynamics of shoreface-connected ridges and tidal sand ridges. These large-scale bedforms are observed on the inner and outer shelf of coastal seas in water depths of 10-20m. The motivation of this work is to improve the understanding of the mechanisms related to their formation and the processes that determine their main characteristics. This is done with the use of idealised morphodynamic models. The basic assumption underlying these models is that large-scale sand ridges can solely form as free instabilities on a flat sea bottom. Mathematical methods based on a stability analysis are applied, whereas analytical and numerical methods are used to solve the equations. Existing models are extended with new physical processes, in particular including the role of grain sorting. An important part of this thesis concerns the unresolved question about the origin of the observed mean grain size pattern over the ridges. It explores the hydrodynamic processes that can lead to sediment sorting and the formation of large-scale sand ridges. The model results indicate that the dynamics for different forcing conditions strongly differ. Shoreface-connected sand ridges mainly form during storm conditions, whereas if fair weather conditions prevail the more offshore located tidal sand ridges develop. A probabilistic formulation of these two realisation of the model is used to find conditions for which both types of large-scale bedforms occur simultaneously, as is the case in the southern North Sea. These conditions turn out to be a low storm fraction and the presence of both tidal and storm-driven currents. The transport of non-uniform sediment is described by formulations for both bed load and suspended load, both of which account for dynamic hiding effects. A one-layer model for the bed evolution is used and two grain size classes (fine and coarse sand) are considered. The results of the model for storm conditions indicate that the

  2. Effects of CO2 Hydrate on Deep-Sea Foraminiferal Assemblages

    SciTech Connect

    Ricketts, E R; Kennett, J P; Hill, T M; Barry, J P

    2005-06-01

    THE EFFECTS OF CO2 HYDRATE ON DEEP-SEA FORAMINIFERAL ASSEMBLAGES E. R. Ricketts*, J. P. Kennett and T. M. Hill Department of Geological Sciences University of California, Santa Barbara, CA USA Jim Barry Monterey Bay Aquarium Research Institute Moss Landing, CA USA ABSTRACT This study, conducted with the Monterey Bay Aquarium Research Institute (MBARI), is the first to investigate potential effects of CO2 hydrates on benthic microfossils, specifically foraminifera. The experiment was conducted in September 2003 aboard the R/V Western Flier using the ROV Tiburon. Experimental (CO2 exposed) and control cores were collected at 3600m and stained to distinguish live (stained) from dead (unstained) individuals. Foraminifera are ideal because of differing test composition (calcareous and agglutinated) and thickness, and diverse epifaunal and infaunal depth preferences. The effects of the CO2 on assemblages have been tracked both vertically (10cm depth) and horizontally, and between live and dead individuals. Increased mortality and dissolution of calcareous forms resulted from exposure to CO2 hydrate. Preliminary results suggest several major effects on surface sediment assemblages: 1) total number of foraminifera in a sample decreases; 2) foraminiferal diversity decreases in both stained and unstained specimens. The number of planktonic and hyaline calcareous tests declines greatly, with milliolids being more resistant to dissolution when stained; and 3) percentage of stained (live) forms is higher. Down-core trends (up to 10cm) indicate: 1) percent agglutinated forms decline and calcareous forms increasingly dominate; 2) agglutinated diversity decreases with depth; and 3) assemblages become increasingly similar with depth to those in control cores not subjected to CO2 hydrate. These results imply almost complete initial mortality and dissolution upon CO2 hydrate emplacement.

  3. Effects of winter convection on the deep layer of the Southern Adriatic Sea in 2012

    NASA Astrophysics Data System (ADS)

    Bensi, M.; Cardin, V.; Rubino, A.; Notarstefano, G.; Poulain, P. M.

    2013-11-01

    We analyze aspects concerning the thermohaline changes observed in the near-bottom layer of the Southern Adriatic Pit (SAP), in the Eastern Mediterranean, after the arrival of abundant and exceptionally dense water (σθ > 30 kg m-3) produced in the shallow Northern Adriatic Sea during winter 2012. For this purpose, we use temperature (T), salinity (S), and current time series collected at the E2M3A deep-ocean observatory of the Southern Adriatic, and Conductivity-Temperature-Depth data obtained both in the Southern and Middle Adriatic from freely drifting profiling floats. The dense water produced in the Northern Adriatic arrived in the central and deepest part of the SAP as a series of individual pulses starting on 10 March 2012; while, a stronger and prolonged signal that significantly modified the local deep water stratification arrived after 10 April 2012. As a consequence, T and S suddenly decreased (≈0.15°C and ≈0.015), thus interrupting positive T and S bottom trends observed during the previous 5 years and producing a density increase of ≈0.02 kg m-3. Such variability has been rarely observed in the area. We ascribe its occurrence to the concomitance of exceptionally harsh and long-lasting Bora wind, scarce precipitation, and low river discharge over the Northern Adriatic during winter 2011/2012. Eventually, this newly formed AdDW reached the Strait of Otranto during July 2012. Its characteristics profoundly differed from those observed in the previous decade. Hence, a noticeable variability in structure and circulation of the abyssal layers of the Ionian basin is likely to occur in the near future.

  4. Analysis of the Effects of Sea Disposal on a One-Ton Container

    NASA Technical Reports Server (NTRS)

    Jackson, Wde C.; Jackson, Karen E.; Fasanella, Edwin L.; Kelley, John

    2007-01-01

    Excess and obsolete stocks of chemical warfare material (CWM) were sea disposed by the United States between 1919 and 1970. One-ton containers were used for bulk storage of CWM and were the largest containers sea disposed. Disposal depths ranged from 300 to 17,000 feet. Based on a Type D container assembly drawing, three independent analyses (one corrosion and two structural) were performed on the containers to address the corrosion res