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Sample records for sea effects obtained

  1. Analysis of 30 Years Sea Surface Elevation (sse) Data Obtained From A Global Ocean Model

    NASA Astrophysics Data System (ADS)

    Wenzel, M.

    In this presentation the sea surface elevation (SSE) as obtained from a global OGCM will be analysed. The model used is the Hamburg LSG model with a 2 degree hori- zontal resolution, 23 layers in the vertical and a 10 day timestep. The model has a free surface and includes the thermo- and halosteric effects. It is integrated for 50 years forced by monthly NCEP reanalyzes data (1950-1999). The last 30 years of model output are analyzed on regional to global scale to judge the role of the different contributions to the interannual sea level variations as there are: horizontal redistribution of volume (mass), surface freshwater flux (precipitaion- evaporation) and steric effects. On the global scale the surface freshwater flux can clearly be identified as the main contributor, while on regional to local scale it is the steric effect.

  2. Effects of sea spray geoengineering

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2012-03-01

    Anthropogenic climate warming is leading to consideration of options for geoengineering to offset rising carbon dioxide levels. One potential technique involves injecting artificial sea spray into the atmosphere. The sea salt particles would affect Earth's radiation budget directly, by scattering incoming solar radiation, and indirectly, by acting as cloud condensation nuclei, which could lead to whiter clouds that reflect more radiation. However, the potential effects of this method, especially the direct effects, are not fully known. Partanen et al. studied the effects of artificial sea spray using climate model simulations. They found that outside of the most heavily clouded regions the direct effect of scattering of radiation was an important part of the total effect. They also examined the effect of particle size and found that decreasing the size of injected particles could improve the efficiency of the geoengineering technique.

  3. Obtaining the correct sea surface temperature: bias correction of regional climate model data for the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Macias, Diego; Garcia-Gorriz, Elisa; Dosio, Alessandro; Stips, Adolf; Keuler, Klaus

    2016-02-01

    Here, the COSMO Climate Limited-area Modelling (CCLM) regional climate model (RCM) is used as external forcing for a Mediterranean basin-scale ocean model based on the general estuarine transport model (GETM). CCLM is forced by different global climate models (GCMs) (MPI and EcEarth) and by the ERA-interim (ERAin) reanalysis. Sea surface temperatures (SST) simulated by the different runs of the ocean model are compared with satellite measurements. As a substantial cold bias in simulated SST is found, a simple bias-correction methodology is applied to the RCM atmospheric variables, namely (1) air temperature (which is usually underestimated for the region by RCMs runs), (2) cloud cover (typically overestimated) and (3) wind intensity (as zonal wind intensity is usually overestimated). The performed analysis identifies wind velocity as the most important variable to correct in order to satisfactorily obtain Mediterranean SST. For many of the RCM realizations significant improvement in the simulated SST are only achieved when wind intensity values were bias-corrected towards observed values. Air temperature and cloud cover had a more marginal importance in reducing the SST bias observed in RCM-forced runs of the ocean model. By comparing the ERAin-driven run and the GCMs driven runs, our analyses suggest that the main source of observed bias is related with the GCMs being used as lateral boundary condition for the RCM realizations. However, a relative simple bias-correction methodology is sufficient to reduce a large part of the induced bias in SST and to improve the vertical water stratification characteristics within the Mediterranean basin that will allow to analyze current and future biogeochemical conditions of the studied basin.

  4. 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.

  5. Multiscroll Chaotic Sea Obtained from a Simple 3D System Without Equilibrium

    NASA Astrophysics Data System (ADS)

    Jafari, Sajad; Pham, Viet-Thanh; Kapitaniak, Tomasz

    Recently, many rare chaotic systems have been found including chaotic systems with no equilibria. However, it is surprising that such a system can exhibit multiscroll chaotic sea. In this paper, a novel no-equilibrium system with multiscroll hidden chaotic sea is introduced. Besides having multiscroll chaotic sea, this system has two more interesting properties. Firstly, it is conservative (which is a rare feature in three-dimensional chaotic flows) but not Hamiltonian. Secondly, it has a coexisting set of nested tori. There is a hidden torus which coexists with the chaotic sea. This new system is investigated through numerical simulations such as phase portraits, Lyapunov exponents, Poincaré map, and frequency spectra. Furthermore, the feasibility of such a system is verified through circuital implementation.

  6. 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

  7. Sea level record obtained from submerged the Great Barrier Reef coral reefs

    NASA Astrophysics Data System (ADS)

    Yokoyama, Y.; Esat, T. M.; Thompson, W. G.; Thomas, A. L.; Webster, J.; Miyairi, Y.; Matsuzaki, H.; Okuno, J.; Fallon, S.; Braga, J.; Humblet, M.; Iryu, Y.; Potts, D. C.

    2013-12-01

    The last glacial is an interesting time in climate history. The growth and decay of large northern hemisphere ice sheets acting in harmony with major changes in ocean circulation amplified climate variations and resulted in severe and rapid climate swings throughout this time. The variability is not limited to climate but includes rapid, large scale changes in sea level recorded by tropical corals (eg., Yokoyama and Esat, 2011 Oceanography). Research done in the last decade using corals provides a better picture of the climate system, though only a few samples older than 15 ka are available. The Integrated Ocean Drilling Program (IODP) Expedition 325 drilled 34 holes across 17 sites in the Great Barrier Reef, Australia to recover fossil coral reef deposits. We recovered reef materials from water depth to 126 m that ranged in age from 9,000 years to older than 30,000 years ago covering several paleoclimatologically important events, including the Last Glacial Maximum. Two transects separated more than 600 km apart show an identical sea-level history thereby verifying the reliability of the records. Radiometrically dated corals and coralline algae indicate periods of rapid sea-level fluctuation at this time, likely due to complex interactions between ocean currents and ice sheets of the North Atlantic.

  8. 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.

  9. Analysis of vector magnetic anomalies over the Bayonnaise Knoll caldera obtained from a deep-sea magnetic exploration by AUV

    NASA Astrophysics Data System (ADS)

    Sayanagi, K.; Isezaki, N.; Matsuo, J.; Harada, M.; Kasaya, T.

    2011-12-01

    Geophysical surveys near the seafloor are very effective methods in order to investigate fine structures of the oceanic crust. Such surveys have increased in researches and developments of the seafloor, and will be more and more necessary in the future. For example, seabed resources like hydrothermal deposits have recently focused attention behind the international situation for natural resources like a competition of resources development. In order to estimate accurate abundance of those resources, the above detailed investigations should be needed because of low resolution of geophysical surveys on the sea and low efficiency of exploratory drilling. From such a viewpoint, we have been developing a measurement system for magnetic explorations using an AUV and a deep-tow system. The magnetic exploration system consists of two 3-axis flux-gate magnetometers, one/two Overhauser magnetometer(s), an optical fiber gyro, a main unit (control, communication, recording), and an onboard unit. These devices except for the onboard unit are installed in pressure cases (depth limit: 6000m). Thus this system can measure three components and total intensity of the geomagnetic field in the deep sea. In 2009, the first test of the magnetic exploration system was carried out in the Kumano Basin using AUV Urashima and towing vehicle Yokosuka Deep-Tow during the R/V Yokosuka YK09-09 cruise. In this test, we sank a small magnetic target to the seafloor, and examined how the system worked. As a result, we successfully detected magnetic anomaly of the target to confirm the expected performance of that in the sea. In 2010, the magnetic exploration system was further tested in the Bayonnaise Knoll area both using a titanium towing frame during the R/V Bosei-maru cruise and using AUV Urashima during the R/V Yokosuka YK10-17 cruise. The purpose of these tests was to evaluate the performance of the system in an actual hydrothermal deposit area for practical applications of that. The

  10. Real time prediction of sea level anomaly data with the Prognocean system - comparison of results obtained using different prediction techniques

    NASA Astrophysics Data System (ADS)

    Mizinski, Bartlomiej; Niedzielski, Tomasz; Kosek, Wieslaw

    2013-04-01

    Prognocean is a near-real time modeling and prediction system elaborated and based at University of Wroclaw, Poland. It operates on gridded Sea Level Anomaly (SLA) data obtained from the Archiving, Validation and Interpretation of Satellite Oceanographic data (AVISO), France. The data acquisition flow from AVISO to Prognocean is entirely automatic and is implemented in Python. The core of the system - including data pre-processing, modeling, prediction, validation and visualization procedures - is composed of a series of R scripts that are interrelated and work at three levels of generalization. The objective of the work presented here is to show the results of our numerical experiment that have been carried out since early 2012. Four prediction models have been implemented to date: (1) extrapolation of polynomial-harmonic model and the extrapolation of polynomial-harmonic model with (2) autoregressive model, (3) threshold autoregressive model and (4) autocovariance procedure. Although the presentation is limited to four models and their predictive skills, Prognocean consists of modules and hence new techniques may be plugged in at any time. In this paper, the comparison of the results into forecasting sea level anomaly maps is presented. Along with sample predictions, with various lead times up to two weeks, we present and discuss a set of root mean square prediction error maps computed in real time after the observations have been available. We identified areas where linear prediction models reveal considerable errors, which may indicate a non-linear mode of sea level change. In addition, we have identified an agreement between the spatial pattern of large prediction errors and the spatial occurrence of key mesoscale ocean eddies.

  11. 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

  12. 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.

  13. 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.

  14. Osteoblast-like cell response to macro- and micro-patterned carbon scaffolds obtained from the sea rush Juncus maritimus.

    PubMed

    López-Álvarez, M; Pereiro, I; Serra, J; de Carlos, A; González, P

    2011-08-01

    Carbon scaffolds with a directional patterned surface were obtained by pyrolysis of the sea rush Juncus maritimus. The structure of the scaffolds was investigated using scanning electron microscopy, mercury porosimetry and interferometric profilometry. X-ray diffraction and x-ray fluorescence were the techniques used for their chemical characterization. The alignment and differentiation of pre-osteoblasts (MC3T3-E1 cell line) incubated on the patterned scaffolds were evaluated by scanning electron microscopy, confocal laser scanning microscopy and by the quantification of the phosphatase alkaline activity and the osteocalcin synthesis. It was found that pyrolysis at 500 °C preserved and even enhanced the natural macro- and micro-patterning of the plant. The results obtained for porosity and chemical composition validated these structures as viable scaffolds for tissue engineering applications. Finally, the patterned surface was confirmed to promote the oriented growth of the pre-osteoblasts MC3T3-E1, not only after short periods of incubation (hours) but also after longer ones (several weeks). The quantification of the cell differentiation markers together with the evaluation of the cell layer morphology up to 28 days of incubation confirmed the differentiation of MC3T3-E1 cells to osteoblasts. PMID:21772087

  15. 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. PMID:16846706

  16. Wave climate of the Hellenic Seas obtained from a wave hindcast for the period 1960-2001

    NASA Astrophysics Data System (ADS)

    Zacharioudaki, Anna; Korres, Gerasimos; Perivoliotis, Leonidas

    2015-06-01

    The wave climate of the Hellenic Seas and particularly the climate extremes are investigated by means of a 42-year (1960-2001) model hindcast. The wave model, implemented over the Mediterranean basin, is forced by high-resolution winds generated upon downscaling of the ERA40 reanalysis. It is shown that the quality of the hindcast is overall satisfactory; however, extreme wave heights in the Aegean Sea are consistently overestimated. Accordingly, corrections to the original data are applied. The results show that the highest mean wave conditions are located east and west of Crete Island where the northerly air flow exits the Aegean Sea. Extreme waves are the highest outside the Aegean Sea, mainly in the southern Ionian Sea and south of Crete. Nevertheless, high waves also develop around the exits of the Aegean Sea and N-NE of the Cyclades islands. Despite a milder extreme wave climate in the Aegean Sea due to short fetch distances, the mean wave height range is very similar to that of the Ionian Sea. Moreover, in summer, the two seas exhibit similar extreme wave height conditions with the highest extremes found around the exits of the Aegean Sea to the Levantine basin. Storms of a longer duration are also observed in the Aegean Sea. The analysis of long-term trends in the wave climate shows that mean and extreme wave climate as well as the average intensity of extreme events have decreased in the Hellenic Seas. Nevertheless, this decrease has not been monotonic. A turning point is located around year 1981 with the mean and extreme wave height mostly increasing before this year and decreasing afterwards.

  17. Obstacle Effects on the River sea Interaction

    NASA Astrophysics Data System (ADS)

    Hwang, J.; Park, Y.

    2008-12-01

    The river discharged flow behavior in the ROFI (Regions of Freshwater Influence; Simpson, 1997) is studied using FVCOM (Chen et al, 2006), an unstructured grid primitive equation model. In the present study we can resolve detailed motion near the river mouth and consider the effect of an obstacle (a sea mount or an island) placed in front of the river mouth. The unstructured grid zooms up the behavior of a bulge which was widely observed in earlier estuarine model studies and we could investigate the separation of the bulge by the anti-cyclonic motion due to the river discharge. An obstacle of a sea mount seems to play a similar role as the core of a bulge, but in the case with an island as an obstacle, totally different flow patterns were observed compared with other cases, since island can affect the surface motions. With the same geometrical conditions, we also consider tide, which enhances vertical mixing and changes flow patterns induced by the river discharge.

  18. 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

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. Sea ice effects on low salinity water transport in the northern East/Japan Sea

    NASA Astrophysics Data System (ADS)

    Lee, H.; Kim, S.; Kwon, M.; Park, J.; Park, Y.

    2012-12-01

    We here simulated the sea ice in the northern East/Japan Sea and investigated its effects on low salinity waters transported along the Primorye coast using an ice-coupled Ocean General Circulation Model, ROMS(Regional Ocean Modeling System). The model area covers the region 126.5°E - 142.5°E, 33°N - 52°N with grid resolution of 1/10° in latitude and longitude. Monthly mean ECMWF forecast data with 0.5° resolution during the period 1999-2008 and ERA interim reanalysis data are used to calculate sea surface fluxes as well as wind stress at the sea surface. Heat and fresh water fluxes are computed with a bulk formula without any relaxation of SST and SSS. Four major tidal forcing (M2, S2, K1, O1) are included along the open boundaries based on TPXO7. The modeled sea ice in the Tatar Strait shows a maximum extent in February and is disappeared in April. Although its duration time is similar to the observed one, the model appears to underestimate the sea ice concentration and area. The melting of sea ice in the Tatar Strait seems to be responsible for low salinity waters along the Primorye coast in spring.

  4. Effect of the Dead Sea-Red Sea canal modelling on the prediction of the Dead Sea conditions

    NASA Astrophysics Data System (ADS)

    Asmar, B. N.; Ergenzinger, Peter

    2003-06-01

    A project to link the Dead Sea to the Red Sea via a canal is undergoing extensive study. In previous works, a generalized mathematical model describing the state of the Dead Sea and a simulation model to implement it have been developed. The model is extended to include the proposed canal project and investigates two alternative modelling canal scenarios: (1) introducing the canal water inflow into the bottom layer or (2) the top layer of the sea. The predicted general effects of the canal are the restoration of the water level of the sea to pre-1970s level; an increase in the total evaporation rate and a decrease in the top layer salinity. Implementing scenario 1, the model predicts that: the water level of the Dead Sea will exceed the desired level design value and therefore shorter filling time can be used; seasonal stratification will persist; total evaporation rate will increase Modestly; there will a small decrease in the salinity of the top layer but a substantial decrease in the salinity of the bottom layer, which will hurt industries severely; there will be a continuation of seasonal crystallization of aragonite and gypsum. Implementing scenario 2 the model predicts that: the water level of the Dead Sea will be maintained at the desired level design value; stratification will be re-established, with the formation of a permanent two-layer system; there will be a substantial increase in the total evaporation rate; the salinity of the top layer will decrease significantly but there will be continuous slower salinity increase in the bottom layer; the crystallization of aragonite will cease, but seasonal gypsum crystallization can be expected to continue as soon as the filling period ends and the canal shifts into normal operation.

  5. 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. PMID:25815925

  6. 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.

  7. BIOLOGICAL EFFECTS: MARINE MAMMALS AND SEA TURTLES

    EPA Science Inventory

    In the description of the Arthur Kill biological features presented in Chapter 1, marine mammals and sea turtles are not discussed since they are not regular residents of this area. owever, marine turtles, seals, and cetaccans are occasionally sighted in the Arthur Kill, and they...

  8. 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.

  9. Analysis of Experimental Sea-level Transient Data and Analog Method of Obtaining Altitude Response for Turbine-propeller Engine with Relay-type Speed Control

    NASA Technical Reports Server (NTRS)

    Vasu, George; Pack, George J

    1951-01-01

    Correlation has been established between transient engine and control data obtained experimentally and data obtained by simulating the engine and control with an analog computer. This correlation was established at sea-level conditions for a turbine-propeller engine with a relay-type speed control. The behavior of the controlled engine at altitudes of 20,000 and 35,000 feet was determined with an analog computer using the altitude pressure and temperature generalization factors to calculate the new engine constants for these altitudes. Because the engine response varies considerably at altitude some type of compensation appears desirable and four methods of compensation are discussed.

  10. Marine organics effect on sea-spray light scattering

    NASA Astrophysics Data System (ADS)

    Vaishya, Aditya; Ovadnevaite, Jurgita; Bialek, Jakub; Jennings, S. G.; Ceburnis, Darius; O'Dowd, Colin

    2013-05-01

    Primary-produced sea-spray is typically composed of sea-salt, but in biologically-active regions, the spray can become enriched with organic matter which reduces hygroscopicity of sea-spray, thereby having a potential impact on aerosol scattering. This study shows that scattering enhancement of marine aerosol, as a function of increasing relative humidity, is reduced when enriched with organics whose results are used to develop a new hygroscopicity growth-factor parameterization for sea-spray enriched in organic matter. The parameterization reveals a dual state which flips from high-hygroscopicity and high-scattering enhancement to low-hygroscopicity and low-scattering enhancement as the organic volume fraction increases from below ˜ 0.55 to above ˜ 0.55. In terms of organic enrichment, the effect on Top of Atmosphere (TOA) direct radiative forcing (ΔF) is to reduce the cooling contribution of sea-spray by ˜ 5.5 times compared to pure sea-salt spray. The results presented here highlight a significant coupling between the marine biosphere and the direct radiative budget through alteration of sea-spray chemical composition, potentially leading to accelerated global warming should biological activity increase with future projected temperature increases.

  11. Tidal currents in the Indonesian Seas and their effect on transport and mixing

    NASA Astrophysics Data System (ADS)

    Hatayama, Takaki; Awaji, Toshiyuki; Akitomo, Kazunori

    1996-05-01

    We have investigated the characteristics of tides and tidal currents in the Indonesian Seas, with particular emphasis on the predominant constituents, the barotropic M2 and K1 components. The calculated harmonic constants of the M2 and K1 tides agree well with those obtained from extensive tide gauge observations: the mean root-mean-square errors between models and observations for M2 and K1 over the entire Indonesian Seas are 11.2 and 8.65 cm, respectively, smaller than previous studies. The features of the tidal current field are qualitatively similar to those reported by Wyrtki [1961]. Relatively strong tidal currents are found in the Java Sea and in the vicinities of the narrow straits, such as the Lombok and Malacca Straits. Tracking of numerous labeled particles in the calculated velocity field clearly shows that the tidal currents play essential roles in the transport and mixing processes in the Indonesian Seas. For example, in the eastern Indonesian Seas a significant clockwise residual circulation appears around Buru Island, due primarily to the tidal rectification over variable bottom topography, with a minor impact from the nonlinear effects around narrow straits. The tide-induced residual transport from the Seram Sea to the eastern Banda Sea attains about 3.8 Sv (1 Sv = 106 m3 s-1), comparable to that of the Indo-Pacific throughflow along the eastern route. In the western Indonesian Seas (the Java Sea and the Makassar Strait) the residual transport is much smaller than the throughflow transport along the western route. Our result suggests, however, that the properties of water flowing through this route could be modified by strong tidal mixing around the shelf of the southern Makassar Strait and the Lombok Strait.

  12. 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.

  13. 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.

  14. 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.

  15. Sea breezes and advective effects in southwest James Bay

    NASA Technical Reports Server (NTRS)

    Mckendry, Ian; Roulet, Nigel

    1994-01-01

    Observations from a transect extending 100 km inland during the Northern Wetlands Study (NOWES) in 1990 show that the sea breeze develops on approximately 25% of days during summer and may penetrate up to 100 km inland on occasions. The sea breeze exhibits a marked diurnal clockwise rotation as a result of the Coriolis effect along the unobstructed coastline. The marine advective effect is shown to depend on gradient wind direction. With northwesterly upper level flow the sea breeze tends to be northeasterly in direction and is associated with decreased temperatures and vapor pressure deficits (VPD). With southwesterly upper level flow the sea breeze tends to have a southeasterly direction and less effect on temperatures and VPD. This is attributed to shorter residence times of air parcels over water. For two cases, Colorado State University mesoscale model simulations show good agreement with surface wind observations and suggest that under northwesterly gradient flow, Bowen ratios are increased in the onshore flow along western James Bay, while during southwesterly gradient flow these effects are negligible. These results have implications for the interpretation of local climate, ecology, and hydrology as well as land-based and airborne turbulent flux measurements made during NOWES.

  16. 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).

  17. DISPERSANT EFFECTIVENESS AT VARIOUS SEA STATES

    EPA Science Inventory

    In 2002, a dispersant effectiveness protocol, which tested the effectiveness of dispersants to disperse crude oil into the water column, was developed. A new and highly reproducible protocol that uses a baffled flask as the primary vehicle for getting the oil dispersed has emerge...

  18. Low-sensitivity acceleration seismic records obtained on sea floor in the source region of the 2004 Sumatra-Andaman Earthquake

    NASA Astrophysics Data System (ADS)

    Shinohara, M.; Yamada, T.; Kanazawa, T.

    2005-12-01

    To understand characteristics of large earthquakes occurred in a subduction zone, it is necessary to study an asperity where large earthquakes occur repeatedly. Because observation near an asperity is needed for studies of asperities, ocean bottom seismometer (OBS) is essential to observe seismic waves from earthquakes in subduction area. Since a conventional OBS is designed for high-sensitivity observation, OBS records of large earthquake occurred near OBS are often saturated. To record large amplitude seismic waves, a servo-type accelerometer is suitable. However it was difficult for OBS to use an accelerometer due to large electric power consumption. Recently a servo-type accelerometer with a large dynamic range and low-power consumption is being developed. In addition, a pressure vessel of OBS can contain much more batteries by using a large size titanium sphere. For the long-term sea floor observation of aftershock of the 2004 Sumatra-Andaman earthquake, we installed a small three-component accelerometer in a conventional long-term OBS and obtained both high-sensitivity seismogram and low-sensitivity (strong motion) accelerograms on the sea floor. We used a compact three-component servo-type accelerometer whose weight is 85 grams as a seismic sensor. Measurement range and resolution of the sensor are 3 G and 10-5 G. The sensor was directly attached to the inside of the pressure vessel. Signals from the accelerometer were digitally recorded to Compact Flash memory with 16 bit resolution and a sampling frequency of 100 Hz. The OBS with the accelerometer was deployed on February 24, 2005 in a southern part of the source region of the 2004 Sumatra-Andaman earthquake by R/V Natsushima belonging to JAMSTEC, and recovered on August 3 by R/V Baruna Jaya I belonging to BPPT, Indonesia. The accelerograms were obtained from the deployment to April 13 when the CF memory became full. Although there are some small troubles for the recording, we could obtain low

  19. 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.

  20. 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.

  1. Effect of Tides On Sea Ice Deformation and Growth Rate

    NASA Astrophysics Data System (ADS)

    Hutchings, J.; Heil, P.; Hibler, W. D.

    Due to high ice strength in present formulations of non-linear plastic sea ice dynamic models, the relatively small tides in the Arctic Basin produces little relative motion. However, recent work with a stand alone sea ice model including a more realistic for- mulation of ice-ocean coupling [Heil & Hibler, accepted] has produced more realistic inertial motion in agreement with observations. With such improved model physics, we expect tidal motion of the ice pack to have a more pronounced effect on simulated periodic lead opening and closing, enhancing winter ice growth rate. To investigate this process, tidal forcing [Kowalik 1998] is included in the momentum balance of a stand alone sea ice model [Heil & Hibler, accepted]. The model includes a modi- fied coulombic rheology, hourly interpolated NCEP reanalysis atmospheric forcing, climatological cloud fraction [Gorshkov,1980] , oceanic currents and heat flux from Polyakov et al. [1998] and inertial embedding as Hibler et al. [1998]. Arctic sea ice is simulated for the period 1948-2000 and compared to a control without tidal forcing. It is investigated how tidal motion and inertial motion interact. As the inertial period is close to the major semi-diurnal tidal period we expect ice deformation in tidally active regions (such as the Barents Sea) to be amplified through inertial resonance. The tidal influence on ice mass balance is estimated. The interannual variability of ice mass is examined to show how tidal influence differs between years of high Arctic Oscillation (AO) index, when ice divergence is increased and trans-polar transport widened, and low AO index, when the Arctic high dominates and convergent motion prevails.

  2. 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

  3. 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

  4. 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.

  5. Geometric effects in SeaWiFS lunar observations

    NASA Astrophysics Data System (ADS)

    Eplee, Robert E.; Patt, Frederick S.; Meister, Gerhard

    2015-09-01

    The radiometric stability requirements for ocean color climate data records place tight constraints on the onorbit calibration of ocean color instruments. A major component of the on-orbit calibration methodology for NASA ocean color sensors is the normalization of lunar observations for variations in observing geometry by the USGS ROLO photometric model of the Moon. SeaWiFS made 204 lunar observations over its 13-year mission. 145 radiometric trending observations were made at low phase angles (-8° to -6° and +5° to +10°). 59 additional observations were made at high phase angles (-49° to -27° and +27° to +66° degrees). The NASA Ocean Biology Processing Group has undertaken a reanalysis of residual geometric effects in the SeaWiFS lunar observations. Ratios of SeaWiFS observations to ROLO model predictions were fit with quadratic functions of phase angle and linear functions of sub-spacecraft point and sub-solar point libration longitude and latitude angles. The resulting phase and libration fit coefficients have been used as additional geometric corrections for the SeaWiFS lunar observations. For the low phase angle observations, the phase corrections are 0.16% and the libration corrections are 0.18%. For the low and high phase angle observations, the phase corrections are 1.8% and the libration corrections are 0.22%. These geometric corrections have reduced the overall scatter in the lunar observations, bringing the high phase angle data into family with the low phase angle measurements without impacting the radiometric response in the low phase angle observations.

  6. 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…

  7. 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

  8. 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. PMID:22710931

  9. Recent and projected changes in Dead Sea level and effects on mineral production from the sea

    USGS Publications Warehouse

    Sauer, Stanley P.

    1978-01-01

    Hydrologic data for the Dead Sea area were reviewed to assess the probable magnitude and rate of change of the water level of the Sea. Historical average annual Dead Sea levels range from a minimum of 399.4 meters below sea level in about 1818 to a maximum of 388.6 meters below in 1896. Present levels are rapidly approaching the historical low. There is a close correlation between Dead Sea level and accumulated departure from the mean of long-term rainfall except for the most recent period since 1964. During that period rainfall has been near the long-term average but water levels have continued to decline, in part due to abstractions for irrigation in the Jordan River basin. The dissolved-solids concentration of Dead Sea water presently is approximately 322,000 milligrams per liter and is generally well mixed. The increase in dissolved solids to the present high concentration has resulted in an evaporation rate less than that estimated in previous reports. An average annual inflow to the Sea of 900 cubic hectometers from all sources is required to stabilize the Sea at the present level. (Woodard-USGS)

  10. 20 CFR 702.421 - Effect of failure to obtain initial authorization.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... with sections 7 (b) and (c) of the Act, 33 U.S.C. 907 (b) and (c) and these regulations; or (b) The... LABOR LONGSHOREMEN'S AND HARBOR WORKERS' COMPENSATION ACT AND RELATED STATUTES ADMINISTRATION AND PROCEDURE Medical Care and Supervision Medical Procedures § 702.421 Effect of failure to obtain...

  11. 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.

  12. Effect of cinitapride in isolated ileum obtained from guinea-pigs treated with morphine.

    PubMed

    Colado, M I; Alfaro, M J; del Val, V L; Martín, M I

    1991-01-01

    1. Cinitapride enhanced the contractile response induced by electrical stimulation in the guinea-pig myenteric plexus-longitudinal muscle strip preparations. 2. The contractile force was significantly increased in strips pretreated with morphine "in vitro" and in tolerant strips. 3. However when tissues were obtained from tolerant guinea-pigs and morphine was not added to the organ bath (morphine-abstinence), the cinitapride effect was significantly decreased. 4. Although further work is required to explain the changes in the effect of cinitapride after acute morphine treatment and in morphine tolerant tissues, the changes observed suggest that some of the cinitapride effects could be linked with the peripheral opioid system. PMID:1662171

  13. 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

  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. Modelled radiative effects of sea spray aerosol using a source function encapsulating wave state

    NASA Astrophysics Data System (ADS)

    Partanen, Antti-Ilari; Dunne, Eimear M.; Bergman, Tommi; Laakso, Anton; Kokkola, Harri; Ovadnevaite, Jurgita; Sogacheva, Larisa; Baisnée, Dominique; Sciare, Jean; Manders, Astrid; O'Dowd, Colin; de Leeuw, Gerrit; Korhonen, Hannele

    2014-05-01

    Sea spray aerosol particles have significant effects on global climate by scattering solar radiation (direct effect) and modifying cloud properties (indirect effect). Sea spray consists mainly of sea salt, but in biologically active regions, major fraction of sea spray may come in the form of primary marine organic matter (PMOM). Traditionally, sea spray flux has been parameterized in global models in terms of wind speed, and organic fraction of sea spray in terms of chlorophyll-a concentration. In this study, we have incorporated recently developed parameterizations for the sea spray aerosol source flux into the global aerosol-climate model ECHAM-HAMMOZ. The parameterizations encapsulate the wave state via Reynolds number, and predict the organic fraction of the sea spray aerosol source flux. The model was then used to investigate the direct and indirect effects of sea spray aerosol particles. We compared simulated sea spray concentrations with in-situ measurements from Mace Head (North Atlantic), Point Reyes (North Pacific), and Amsterdam Island (Southern Indian Ocean). Aerosol optical depth (AOD) was compared with satellite measurements from PARASOL. Modelled annual mean global emissions of sea salt and PMOM were 805 Tg yr-1 (uncertainty range of 378-1233 Tg yr-1) and 1.1 Tg yr-1 (0.5-1.8 Tg yr-1), respectively. Sea salt emissions were considerably lower than the majority of previous estimates, but PMOM was in the range of previous studies. The model captured sea salt concentrations fairly well in the smaller size ranges at Mace Head (annual normalized mean bias of -13% for particles with vacuum aerodynamic diameter Dva

  17. 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.

  18. [Obtaining and characteristics of domestic preparation interferon alpha-2b with prolonged effect].

    PubMed

    Pokholenko, Ia A; Porubleva, L V; Dubeĭ, I Ia; Rebriev, A V; Sutugina, L P; Gromovoĭ, T Iu; Pokrovskiĭ, V A; Obolenskaia, M Iu; Chernykh, S I

    2008-01-01

    Pegylated interferon alpha-2b (PEG-IFN alpha-2b) is a domestic preparation of a modified recombinant interferon alpha-2b with prolonged effect. The preparation was obtained by N-terminal pegylation of IFN alpha-2b with polyethylene glycol (PEG). This paper presents the method of PEG-IFN alpha-2b synthesis and characteristics of the obtained product. PAAG electrophoresis, Western blot analysis and MALDI-TOF mass-spectrometry confirm that the preparation is an N-terminal pegylated IFN alpha-2b that contains no more than 10% of dipegylated IFN alpha-2b. The comparison of PEG-IFN alpha-2b with its foreign analogue has revealed the similarity of their biological activity and pharmacokinetic parameters. PMID:19351063

  19. 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.

  20. Effects of sea spray evaporation and dissipative heating on intensity and structure of tropical cyclone

    NASA Astrophysics Data System (ADS)

    Cheng, Xiaoping; Fei, Jianfang; Huang, Xiaogang; Zheng, Jing

    2012-07-01

    To examine effects of sea spray evaporation and dissipative heating on structure and intensity of a real tropical cyclone, the sea spray flux parameterization scheme was incorporated into the fifth-generation Pennsylvania State University-National Center for Atmospheric Research Mesoscale Model (MM5). Sensitivity tests were performed with varying the spray source function intensities and with and without dissipation heating. The numerical results indicate that sea spray evaporation increases the interfacial sensible heat flux, which is increased by 16% for the moderate spray and 47% for the heavy spray, but has little effect on the interfacial latent heat flux. The net effect of sea spray evaporation is to decrease the total sensible heat flux and to increase the total latent heat flux. The total enthalpy flux is increased by 1% and 12% with moderate and strong spray amounts, respectively. Consistent with these results, the intensity of the tropical cyclone is increased by 5% and 16% in maximum 10-m wind speed, respectively, due to sea spray evaporation. Sea spray evaporation and dissipative heating modify the tropical cyclone structure in important but complex ways. The effect of sea spray on the near-surface temperature and moisture depends on the spray amounts and its location within the tropical cyclone. Within the high-wind region of a tropical cyclone, the lower atmosphere becomes cooler and moister due to the evaporation of sea spray. However, the dissipative heating offsets the cooling due to sea spray evaporation, which makes the lower atmosphere warmer.

  1. Antiallergic effects of pigments isolated from green sea urchin (Strongylocentrotus droebachiensis) shells.

    PubMed

    Pozharitskaya, Olga N; Shikov, Alexander N; Makarova, Marina N; Ivanova, Svetlana A; Kosman, Vera M; Makarov, Valery G; Bazgier, Václav; Berka, Karel; Otyepka, Michal; Ulrichová, Jitka

    2013-12-01

    This study was undertaken to evaluate possible antiallergic effects of an extract of pigments from green sea urchin (Strongylocentrotus droebachiensis) shells. Effects were studied on animal models - guinea pig ileum contraction, rabbit eyes allergic conjunctivitis, and rabbit local skin irritation. The extract significantly reduced, in a dose-dependent manner, the histamine-induced contractions of the isolated guinea pig ileum with ID50 =1.2 µg/mL (in equivalents of spinochrome B), had an inhibitory effect on the model of ocular allergic inflammation surpassing the reference drug olopatadine, and did not show any irritating effect in rabbits. The extract predominantly contained polyhydroxy-1,4-naphthoquinone which would be responsible for the pharmacological activity. The active compounds of the extract were evaluated in silico with molecular docking. Molecular docking into H1R receptor structures obtained from molecular dynamic simulations showed that all spinochrome derivatives bind to the receptor active site, but spinochrome monomers fit better to it. The results of the present study suggest possibilities for the development of new agents for treating allergic diseases on the base of pigments from sea urchins shells. PMID:24288292

  2. 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.

  3. 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.

    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

  4. 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.

    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 long-term 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

  5. 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

    2015-11-01

    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.

  6. 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.

  7. Mechanical cycling effects at Fe-Mn-Si-Cr-Ni SMAs obtained by powder metallurgy

    NASA Astrophysics Data System (ADS)

    Pricop, B.; Söyler, U.; Comčneci, R. I.; Özkal, B.; Bujoreanu, L. G.

    Specimens from Fe-Mn-Si-Cr-Ni SMA, obtained by powder metallurgy and compacted through hot rolling, were subjected to tensile loading-unloading cycles. The pseudoelastic parameters were determined based on recorded stress-strain curves, and their variation tendency with increasing the number of mechanical cycles was discussed. The gauges of tensile specimens were cut after mechanical cycling and were subjected to structural and dilatometric analysis. The structure was analyzed by XRD and SEM, aiming to reveal mechanical cycling effects. The thermomechanical response on heating, of mechanically cycled specimens, was recorded by dilatometry and revealed a tendency to enhance thermal expansion as an effect of increasing the number of cycles. The microstructural changes, induced by mechanical cycling, consisted in the stress induced formation of α' martensite.

  8. Two bootstrapping routines for obtaining imprecision estimates for nonparametric parameter distributions in nonlinear mixed effects models.

    PubMed

    Baverel, Paul G; Savic, Radojka M; Karlsson, Mats O

    2011-02-01

    When parameter estimates are used in predictions or decisions, it is important to consider the magnitude of imprecision associated with the estimation. Such imprecision estimates are, however, presently lacking for nonparametric algorithms intended for nonlinear mixed effects models. The objective of this study was to develop resampling-based methods for estimating imprecision in nonparametric distribution (NPD) estimates obtained in NONMEM. A one-compartment PK model was used to simulate datasets for which the random effect of clearance conformed to a (i) normal (ii) bimodal and (iii) heavy-tailed underlying distributional shapes. Re-estimation was conducted assuming normality under FOCE, and NPDs were estimated sequential to this step. Imprecision in the NPD was then estimated by means of two different resampling procedures. The first (full) method relies on bootstrap sampling from the raw data and a re-estimation of both the preceding parametric (FOCE) and the nonparametric step. The second (simplified) method relies on bootstrap sampling of individual nonparametric probability distributions. Nonparametric 95% confidence intervals (95% CIs) were obtained and mean errors (MEs) of the 95% CI width were computed. Standard errors (SEs) of nonparametric population estimates were obtained using the simplified method and evaluated through 100 stochastic simulations followed by estimations (SSEs). Both methods were successfully implemented to provide imprecision estimates for NPDs. The imprecision estimates adequately reflected the reference imprecision in all distributional cases and regardless of the numbers of individuals in the original data. Relative MEs of the 95% CI width of CL marginal density when original data contained 200 individuals were equal to: (i) -22 and -12%, (ii) -22 and -9%, (iii) -13 and -5% for the full and simplified (n = 100), respectively. SEs derived from the simplified method were consistent with the ones obtained from 100 SSEs. In conclusion

  9. Effect of Diets Supplemented with Different Sources of Astaxanthin on the Gonad of the Sea Urchin Anthocidaris crassispina

    PubMed Central

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

    2012-01-01

    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. PMID:23016124

  10. Idealized WRF model sensitivity simulations of sea breeze types and their effects on offshore windfields

    NASA Astrophysics Data System (ADS)

    Steele, C. J.; Dorling, S. R.; von Glasow, R.; Bacon, J.

    2013-01-01

    The behaviour and characteristics of the marine component of sea breeze cells have received little attention relative to their onshore counterparts. Yet there is a growing interest and dependence on the offshore wind climate from, for example, a wind energy perspective. Using idealized model experiments, we investigate the sea breeze circulation at scales which approximate to those of the southern North Sea, a region of major ongoing offshore wind farm development. We also contrast the scales and characteristics of the pure and the little known corkscrew and backdoor sea breeze types, where the type is pre-defined by the orientation of the synoptic scale flow relative to the shoreline. We find, crucially, that pure sea breezes, in contrast to corkscrew and backdoor types, can lead to substantial wind speed reductions offshore and that the addition of a second eastern coastline emphasises this effect through generation of offshore "calm zones". The offshore extent of all sea breeze types is found to be sensitive to both the influence of Coriolis acceleration and to the boundary layer scheme selected. These extents range, for example for a pure sea breeze produced in a 2 m s-1 offshore gradient wind, from 0 km to 21 km between the Mellor-Yamada-Nakanishi-Niino and the Yonsei State University schemes respectively. The corkscrew type restricts the development of a backdoor sea breeze on the opposite coast and is also capable of traversing a 100 km offshore domain even under high along-shore gradient wind speed (>15 m s-1) conditions. Realistic variations in sea surface skin temperature and initializing vertical thermodynamic profile do not significantly alter the resulting circulation, though the strengths of the simulated sea breezes are modulated if the effective land-sea thermal contrast is altered. We highlight how sea breeze impacts on circulation need to be considered in order to improve the accuracy of both assessments of the offshore wind energy climate and

  11. 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...

  12. 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

  13. Effect of sea water interaction on strontium isotope composition of deep-sea basalts

    USGS Publications Warehouse

    Julius, Dasch E.; Hedge, C.E.; Dymond, J.

    1973-01-01

    Analyses of rim-to-interior samples of fresh tholeiitic pillow basalts, deuterically altered holocrystalline basalts, and older, weathered tholeiitic basalts from the deep sea indicate that 87Sr 86Sr ratios of the older basalts are raised by low temperature interaction with strontium dissolved in sea water. 87Sr 86Sr correlates positively with H2O in these basalts; however, there is little detectable modification of the strontium isotope composition in rocks with H2O contents less than 1%. The isotope changes appear to be a function of relatively long-term, low-temperature weathering, rather than high-temperature or deuteric alteration. Strontium abundance and isotopic data for these rocks suggest that strontium content is only slightly modified by interaction with sea water, and it is a relatively insensitive indicator of marine alteration. Average Rb-Sr parameters for samples of apparently unaltered basalt are: Rb = 1.11 ppm; Sr = 132 ppm; 87Sr 86Sr = 0.70247. ?? 1973.

  14. Effectiveness of spray congealing to obtain physically stabilized amorphous dispersions of a poorly soluble thermosensitive API.

    PubMed

    Kulthe, Viraj Vitthal; Chaudhari, Pravin Digambar

    2014-12-01

    An amorphous phase produced by micronization up to the molecular or colloidal level of a poorly soluble drug having low lipophilicity can distinctly enhance its solubility characteristics. However, though dispersing the molten mass of a poorly water-soluble drug within polymeric matrix has been found to be most effective in formation of molecular dispersions, the drug molecules which melt at high temperature also accompanied by decomposition, such as acetazolamide, are difficult to formulate as molecular dispersions. Hence, a method is proposed to obtain molecular dispersions of acetazolamide with poloxamer-237 by spray congealing under optimal heat treatment. Uniform molecular and/or colloidal dispersions of the drug were achieved with instantaneous solvent evaporation by mixing a drug solution with molten mass of the plasticizer matrix. Immobilization of dispersed drug molecules was effected subsequently through rapid solidification by spray congealing. Initial characterization of 1:1, 1:1.5, and 1:2 ratios of solid dispersions and devitrification study of an optimized (1:2) ratio ensured efficacy of the proposed method in formation of physically stabilized amorphous systems without thermal degradation and hence resulted in more than ninefold rise in solubility and more than 90% dissolution within initial 10 min. With 1:2 ratio, molecular dispersions could be achieved by initial solvent evaporation stage, which when subjected to spray congealing produced physically stable amorphous systems, without signs of thermal degradation. This study also proposes an opportunity for selection of those polymers with which the drug is immiscible in their fluid state, yet obtaining molecular dispersions. PMID:24934386

  15. Effect of sea wave age on scatterometer measurements and wind speed retrieval accuracy

    NASA Astrophysics Data System (ADS)

    Panfilova, Maria; Karaev, Vladimir; Jie, Guo

    2015-04-01

    Radiolocation data is widely used for the wind field retrieval over the sea surface. Wind speed is obtained from the radar cross-section. The backscattered signal contains information about the sea surface but not about the wind vector. This means that at the fixed wind speed the radar backscattering cross-section (RCS) depends on the sea maturity. In the present work the influence of the sea state at RCS and wind speed retrieval accuracy was investigated. The collocated array of ERS scatterometer and sea buoys data was processed. Buoy data were used to determine the wave age and all the dataset was separated into three parts: developing wind waves, fully developed waves and mixed sea. It was shown that error of wind retrieval algorithms for scatterometers (CMOD in this case) depends on the sea state. Wind speed is overestimated for swell-dominant sea and underestimated for developing waves. The direct problem of RCS dependence on the wind vector and sea state was also concidered. The large-scale waves slope variance is a very important parameter that implicitly influences the RCS in case of Bragg scattering and depends on the sea state. The buoy data were used to estimate the slope variance. The algorithm based on artificial neural networks taking into account the slope variance for RCS retrieval was proposed and performed better agreement with the measured RCS than CMOD5. It was shown that RCS increases with the slope variance growth other conditions being equal. Thus wind speed retrieval accuracy can be increased by taking into account sea waves parameters and regional peculiarities. Acknowledgments. This work was supported by Russian Foundation for Basic Research grants 130500852a, 14-05-31517mol-a.

  16. Geometric effects of an inhomogeneous sea ice cover on the under ice light field

    NASA Astrophysics Data System (ADS)

    Katlein, Christian; Perovich, Donald; Nicolaus, Marcel

    2016-02-01

    Light measurements in the ocean provide crucial information about the energy fluxes in the climate and ecosystem. Currently radiative transfer problems are usually considered in horizontally homogeneous layers although it is known to be a crude assumption in many cases. In this paper, we examine the effects of a horizontally inhomogeneous sea ice layer on the light field in the water underneath. We implemented a three dimensional model, capable to simulate the light field underneath arbitrary surface geometries using ray optics. The results show clear effects of the measurement geometry on measured fluxes obtained with different sensor types, which need to be taken into account for the correct interpretation of the data. Radiance sensors are able to better sense the spatial variability of ice optical properties as compared to irradiance sensors. Furthermore we show that the determination of the light extinction coefficient of water from vertical profiles is complicated under a horizontally inhomogeneous ice cover. This uncertainty in optical properties of the water, as well as the measurement geometry also limits the possibility to correct light measurements taken at depth for the influence of water in between the sea ice and the sensor.

  17. Idealized WRF model sensitivity simulations of sea breeze types and their effects on offshore windfields

    NASA Astrophysics Data System (ADS)

    Steele, C. J.; Dorling, S. R.; von Glasow, R.; Bacon, J.

    2012-06-01

    The behaviour and characteristics of the marine component of sea breeze cells have received little attention relative to their onshore counterparts. Yet there is a growing interest and dependence on the offshore wind climate from, for example, a wind energy perspective. Using idealized model experiments, we investigate the sea breeze circulation at scales which approximate to those of the Southern North Sea, a region of major ongoing offshore wind farm development. We also contrast the scales and characteristics of the pure and the little known corkscrew and backdoor sea breeze types, where the type is pre-defined by the orientation of the synoptic scale flow relative to the shoreline. We find, crucially, that pure sea breezes, in contrast to corkscrew and backdoor types, can lead to substantial wind speed reductions offshore and that the addition of a second eastern coastline emphasises this effect through generation of offshore "calm zones". The offshore extent of all sea breeze types is found to be sensitive to both the influence of Coriolis acceleration and to the boundary layer scheme selected. These extents range, for example for a pure sea breeze produced in a 2 m s-1 offshore gradient wind, from 10 km to 40 km between the Mellor-Yamada-Nakanishi-Niino and the Yonsei State University schemes, respectively. The corkscrew type restricts the development of a backdoor sea breeze on the eastern coast and is also capable of traversing a 100 km offshore domain even under high gradient wind speed (>15 m s-1) conditions. Realistic variations in sea surface skin temperature during the sea breeze season do not significantly affect the circulation, suggesting that a thermal contrast is only needed as a precondition to the development of the sea breeze. We highlight how sea breeze impacts on circulation need to be considered in order to improve the accuracy of assessments of the offshore wind energy climate.

  18. Effects of ultrasonic disintegration of excess sludge obtained in disintegrators of different constructions.

    PubMed

    Zielewicz, Ewa; Tytła, Malwina

    2015-01-01

    The ultrasonic disintegration of excess sludge is placed after the mechanical thickening but before the digestion tanks in order to intensify the process of sludge stabilization. The effects obtained directly after ultrasonic disintegration depend on many factors and can be grouped in two main categories: factors affecting the quality of sludge and those associated with the construction of disintegrators and its parameters. The ultrasonic disintegration research was carried out using three types of structural solutions of disintegrators. Two of them, that is, WK-2000 ultrasonic generator (P = 400 W) working with a thin sonotrode and WK-2010 ultrasonic generator (P = 100-1000 W) working with a new type construction emitter lens sonotrode, were compared with the influence of a washer with a flat emitter. The investigations have shown that in the same sludge, using the same value of volumetric energy, the resulting effect depends on the construction of the ultrasonic disintegrator, that is, design of the head and the ratio between the field of the emitter and the field of the chamber in sonicated medium. PMID:25732595

  19. 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

  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. 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.

  2. Exposure of sea bream (Sparus aurata) to toxic concentrations of benzo[a]pyrene: possible human health effect.

    PubMed

    Zena, R; Speciale, A; Calabrò, C; Calò, M; Palombieri, D; Saija, A; Cimino, F; Trombetta, D; Lo Cascio, P

    2015-12-01

    Polycyclic aromatic hydrocarbons (PAHs) can accumulate in the food chain, due to their lipophilic properties. Fish can accumulate contaminants including PAHs and frequent consumption of such contaminated fish can pose risk to human health. The aim of this study was to clarify if acute exposure of sea bream (Sparus aurata, a fish species of great economic importance in the Atlantic and Mediterranean areas) to a PAH, benzo[a]pyrene (B[a]P), at a dose that can induce CYP1A and pathological changes in fish gills, liver and muscle, can induce accumulation in muscle. We investigated the cytotoxic effects (as changes in cell viability, DNA laddering and glutathione content) of in vitro exposure of human peripheral blood mononuclear cells (PBMCs) to organic extracts obtained from muscle of sea breams previously exposed via water to B[a]P (2mg/l, for 12, 24 and 72 h). At this level of exposure, B[a]P caused morphological changes, inflammatory response and CYP1A induction not only in sea bream gills and liver but also in muscle; furthermore, in fish muscle we observed a substantial B[a]P accumulation, which may be associated with the increased CYP1A activity in liver and especially in muscle. However, when PBMCs were exposed to organic extracts obtained from sea bream muscle contaminated with B[a]P, a toxic, although modest effect was revealed, consisting in a significant decrease in cell glutathione levels without alterations in cell viability and DNA laddering. This suggests that consumption of sea breams from B[a]P contaminated waters might represent a risk for human health. PMID:26232038

  3. 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.

  4. 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

  5. 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.

  6. Effect of changes in sympathovagal balance on the accuracy of heart rate variability obtained from photoplethysmography

    PubMed Central

    CHEN, XIANG; HUANG, YUAN-YUAN; YUN, FENG; CHEN, TIAN-JUN; LI, JIN

    2015-01-01

    Heart rate variability (HRV) obtained using photoplethysmography (PPG), which is also known as pulse rate variability (PRV), has already been used in clinical practice. However, it is uncertain whether PRV reflects changes in autonomic nervous function accurately. The aim of the present study was to evaluate quantitatively the effect of alterations in the sympathovagal balance on the agreement between PRV and HRV from electrocardiographs (ECG). Healthy subjects (male, 26; female, 7; age, 22–25 years old) participated in the present study. Paced respiration with 15 breathes/min and breath holding (apnea) were performed to alter the autonomic nervous states of patients. The changes in the low-to-high frequency power ratio (LF/HF) of HRV indicated that there was a sympathovagal balance shift toward vagal predominance during paced respiration, but toward sympathetic predominance during apnea. The results demonstrated that, during paced respiration, all indices had an acceptable agreement [Bland-Altman ratio (BAr)<0.2] between PRV and HRV, with the exception of LF/HF that had an insufficient agreement (BAr=0.25). All indices had very strong correlations [Pearson's correlation coefficients (CC)>0.99] and PRV had a minor but highly significant (P<0.001) increase for the majority of the variability indices, when compared with HRV. During apnea, the discrepancy of the short-term variability indices between PRV and HRV became sizeable with a BAr>0.3 and a minimum CC of 0.96. In conclusion, a decrease of LF/HF caused a marginal inaccuracy of PRV in the indication of sympathovagal balance, while sympathetic activation increased differences in short-term variability between PRV and HRV. PMID:26668634

  7. 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.

  8. 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.

  9. Effects of gravity on spicule formation in cultured micromeres of sea urchin embryo

    NASA Astrophysics Data System (ADS)

    Izumi-Kurotani, A.; Kiyomoto, M.; Imai, M.; Eguchi, H.

    2006-01-01

    To investigate the effects of gravity on morphogenesis at the cellular level, we have proposed a new experimental system with micromeres from sea urchin embryos [Izumi-Kurotani, A., Kiyomoto, M. Morphogenesis and gravity in a whole Amphibian Embryo and in isolated blastomeres of sea urchins, in: Marthy, H. -J. (Ed.), Developmental Biology Research in Space. Adv. Space Biol. Med. vol. 9, Elsevier, Amsterdam, pp. 83 99, 2003]. We studied spicule formation in cultured micromeres of sea urchin embryo under various conditions of gravity: hypergravity by a centrifuge and simulated microgravity in a vertical clinostat. Spicule elongation was suppressed under both experimental conditions.

  10. A numerical study of the effects of a large sandbar upon sea breeze development

    NASA Technical Reports Server (NTRS)

    Kessler, R. C.; Pielke, R. A.; Mcqueen, J.; Eppel, D.

    1985-01-01

    Two-dimensional numerical simulations of sea breeze development over a large sandbar on the North Sea coast of Germany are reported. The numerical model used in these experiments contains a detailed treatment of soil moisture, which allows evaluation of the effects of differential surface characteristics on the airflow pattern. Results of the simulations indicate that the contrast between the moist sandbar and adjacent dry land, the tidal inundation of the sandbar, and the westward penetration of the Baltic sea breeze play important roles in the development of mesoscale airflow patterns in the sandbar region.

  11. 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.

  12. 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.

  13. Seasonal variations in sea ice motion and effects on sea ice concentration in the Canada Basin

    NASA Astrophysics Data System (ADS)

    Serreze, Mark C.; Barry, Roger G.; McLaren, Alfred S.

    1989-08-01

    Drifting buoy data, surface pressure, and geostrophic wind analyses from the Arctic Ocean Buoy Program are used to examine seasonal features of the sea ice motion in the Canada Basin for 1979-1985. Although the 7-year annual mean motion in this region is clockwise, the month-to-month motion is highly variable. In late summer to early autumn, the circulation can become net anticlockwise for periods lasting at least 30 days. Results from a linear model demonstrate that these "reversals" of ice motion in the Beaufort Gyre are a wind-driven response to persistent cyclonic activity that contrasts sharply with the predominantly anticyclonic regimes of spring, late autumn, and winter. Model-predicted ice divergences of 0.5% or more per day which can occur during periods of anticlockwise ice motion are in good agreement with values calculated from optimally interpolated velocity gradient fields. Visible band imagery and passive microwave data confirm associated large areal reductions in ice concentration of approximately 20%. Data from under-ice submarine sonar transects and surface pressure records prior to the study period point to frequent recurrences of these late summer to early autumn ice conditions.

  14. Sea-breeze front effects on boundary-layer aerosols at a tropical coastal station

    SciTech Connect

    Moorthy, K.K.; Murthy, B.V.K.; Nair, P.R. )

    1993-07-01

    The effects of sea breeze on optical depth, size distribution, and columnar loading of aerosols at the tropical coastal station of Trivandrum are studied. It has been observed that sea-breeze front activity results in a significant and short-lived enhancement in aerosol optical depth and columnar loading in contrast to the effects seen on normal sea-breeze days. Examination of the changes in columnar aerosol size distribution associated with sea-breeze activity revealed an enhancement of small-particle (size less than 0.28 [mu]m) concentration. The aerosol size distribution deduced from optical depth measurements generally show a pronounced bimodal structure associated with the frontal activity. 22 refs., 12 figs., 1 tab.

  15. Modeling of topographic effects on Antarctic sea ice using multivariate adaptive regression splines

    NASA Technical Reports Server (NTRS)

    De Veaux, Richard D.; Gordon, Arnold L.; Comiso, Joey C.; Bacherer, Nadine E.

    1993-01-01

    The role of seafloor topography in the spatial variations of the southern ocean sea ice cover as observed (every other day) by the Nimbus 7 scanning multichannel microwave radiometer satellite in the years 1980, 1983, and 1984 is studied. Bottom bathymetry can affect sea ice surface characteristics because of the basically barotropic circulation of the ocean south of the Antarctic Circumpolar current. The main statistical tool used to quantify this effect is a local nonparametric regression model of sea ice concentration as a function of the depth and its first two derivatives in both meridional and zonal directions. First, we model the relationship of bathymetry to sea ice concentration in two sudy areas, one over the Maud Rise and the other over the Ross Sea shelf region. The multiple correlation coefficient is found to average 44% in the Maud Rise study area and 62% in the Ross Sea study area over the years 1980, 1983, and 1984. Second, a strategy of dividing the entire Antarctic region into an overlapping mosaic of small areas, or windows is considered. Keeping the windows small reduces the correlation of bathymetry with other factors such as wind, sea temperature, and distance to the continent. We find that although the form of the model varies from window to window due to the changing role of other relevant environmental variables, we are left with a spatially consistent ordering of the relative importance of the topographic predictors. For a set of three representative days in the Austral winter of 1980, the analysis shows that an average of 54% of the spatial variation in sea ice concentration over the entire ice cover can be attributed to topographic variables. The results thus support the hypothesis that there is a sea ice to bottom bathymetry link. However this should not undermine the considerable influence of wind, current, and temperature which affect the ice distribution directly and are partly responsible for the observed bathymetric effects.

  16. 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.

  17. Sustainable Phosphorus Loadings from Effective and Cost-Effective Phosphorus Management Around the Baltic Sea

    PubMed Central

    Bryhn, Andreas C.

    2009-01-01

    Nutrient over-enrichment of the Baltic Sea, accompanied by intensified algal blooms and decreasing water clarity, has aroused widespread concern in the surrounding countries during the last four decades. This work has used a well-tested dynamic mass-balance model to investigate which decrease in total phosphorus loading would be required to meet the environmental goal to restore the trophic state in the Baltic Sea to pre-1960s levels. Furthermore, the extent to which various abatement options may decrease the phosphorus loading in a cost-effective manner has been studied. Upgrading urban sewage treatment in the catchment could, alone or in combination with banning phosphates in detergents, be sufficient to meet the set environmental goal, at an estimated annual basin-wide cost of 0.21–0.43 billion euro. Such a plan would potentially decrease the total phosphorus loading to the Baltic Sea with 6,650–10,200 tonnes per year. PMID:19412551

  18. 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.

  19. 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…

  20. 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.

  1. 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.

  2. 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.

  3. SST Variability over the Southern South China Sea: Local effects and Remote forcing

    NASA Astrophysics Data System (ADS)

    Thompson, B.; Tkalich, P.

    2012-04-01

    The South China Sea (SCS) is one of the largest semi-enclosed marginal seas in the world ocean. The SCS is connected to the East China Sea through the Taiwan Strait to the northeast and the Pacific Ocean in the east through the Luzon Strait, laying between the Luzon and Taiwan Islands. To the south, SCS is connected to the Indonesian Sea (IS) through the Karimata and Gaspar Straits, and to the Indian Ocean though the Malacca Strait. The large-scale circulation and SST over the SCS is dominantly influenced by the seasonal reversal of the monsoon winds. Beyond the seasonal time scale, the circulation and temperature variability over the SCS demonstrate strong relationship with the El Niño/Southern Oscillation (ENSO) events in the Pacific Ocean. The present study addresses the inter-annual variability of Sea Surface Temperature (SST) over the southern South China Sea with special emphasis on the ENSO and Indian Ocean Dipole (IOD) events during the period 1993 to 2009. Due to its geographical location, the dynamics and thermodynamics of the southern SCS is largely influenced by the anomalous events occurring in the Pacific and Indian Oceans. A high resolution, three-dimensional sigma co-ordinate, regional ocean general circulation model (ROMS) configured for the South China Sea and Bay of Bengal region is used for the analysis. The model has been forced by 12-hourly varying surface wind, air temperature, relative humidity, surface downward solar and longwave radiation and precipitation fields obtained from the ERA-interim re-analysis data set as well as space- and time-dependent lateral fluxes of temperature, salinity, currents and sea level. Detailed analysis has been done to identify the roles of the surface heat fluxes, and the water mass advection from the Java Sea and northern South China Sea in driving the SST variability over the region. The surface heat flux data set (NOC v2.0) developed by the National Oceanography Centre, Southampton, is also used to

  4. 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.

  5. 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.

  6. 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.

  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. PMID:25728358

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. 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

  18. Effect of blood handling conditions on progesterone assay results obtained by chemiluminescence in the bitch.

    PubMed

    Tahir, M Z; Thoumire, S; Raffaelli, M; Grimard, B; Reynaud, K; Chastant-Maillard, S

    2013-10-01

    Assay of blood progesterone (P4) is commonly practiced to determine the time of ovulation, diagnose luteal insufficiency, and predict time of parturition in bitches. Because of practical constraints, most blood samples cannot be assayed on site immediately after collection. The aim of this work was to evaluate the effects of various sampling and storage conditions on concentrations of P4 as determined by chemiluminescence immunoassay. The blood of 5 Beagle bitches was collected from the jugular vein to study the effect of the type of collection tube (silicone, lithium heparin, EDTA), the storage time of unseparated or separated plasma (2 h to 14 d), and the number of freeze-thaw cycles (1-10) on P4. The effect of each factor was tested within one assay session. None of the factors significantly affected P4. Thus, P4 appears to remain relatively stable in canine blood samples exposed to various processing and storage conditions. PMID:23988180

  19. 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

  20. 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

  1. Effect of seasonal changes on the gelling properties of farmed sea bass (Dicentrarchus labrax).

    PubMed

    Cardoso, Carlos L; Mendes, Rogério O; Vaz-Pires, Paulo; Nunes, Maria L

    2014-01-01

    The effect of seasonal changes (summer versus winter) upon the quality of heat-induced gel products from farmed sea bass (Dicentrarchus labrax) was studied. Moreover, the effect of microbial transglutaminase addition (0.5%, w/w) on the quality was assessed. Fat content of gel products attained from sea bass grown during summer was higher (12.0% versus 7.6%). Textural properties of the gels from the summer fish were higher. Protein of gels from winter fish was less soluble in SDS + DTT (sodium dodecyl sulphate, SDS; dithiothreitol, DTT). Contrary to some literature, higher fat level may have played a protective role during processing. Accordingly, season via fat content variation had a strong effect on the gelling ability of heat-induced gels prepared from sea bass. PMID:23733821

  2. 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. PMID:26572377

  3. 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.

  4. 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

  5. Effect of the tidal mixing on the average climatic characteristics of the Barents Sea

    NASA Astrophysics Data System (ADS)

    Kagan, B. A.; Sofina, E. V.

    2015-11-01

    The results of two numerical experiments on the determination of the climate of the Barents Sea obtained using the 3D finite element model hydrostatic model QUODDY-4 are presented. One of the experiments is carried out with the wind + thermohaline + tidal forcing, while the second is conducted without taking into account the tidal component. It is shown that the climate in the Barents Sea is experiencing significant changes associated with the tidal forcing. Thus, maximum differences between two solutions are approximately ±1.0°C for the temperature and ±0.4‰ for seawater salinity at the pycnocline depth. The same conclusion follows from the comparison of the diapycnal diffusion coefficient that characterizes the influence of internal tidal waves and the "background" diffusion coefficient determined by total forcing (including tidal forcing). Predicted values of the background diffusion coefficient are of the same order of magnitude as the ones observed by microstructural measurements of shear in velocity, temperature, and electrical conductivity of sea water in the centers of intense mixing in the marginal zone of the sea ice in the Barents Sea.

  6. Effect of wavelength selection on the accuracy of blood oxygen saturation estimates obtained from photoacoustic images

    NASA Astrophysics Data System (ADS)

    Hochuli, Roman; Beard, Paul C.; Cox, Ben

    2015-03-01

    In photoacoustic tomography (PAT) the image contrast is due to optical absorption, and because of this PAT images are sensitive to changes in blood oxygen saturation (sO2). However, this is not a linear relationship due to the presence of a non-uniform light fluence distribution. In this paper we systematically evaluate the conditions in which an approximate linear inversion scheme-which assumes the internal fluence distribution is unchanged when the absorption coefficient changes-can give accurate estimates of sO2. A numerical phantom of highly vascularised tissue is used to test this assumption. It is shown that using multiple wavelengths over a broad range of the near-infrared spectrum yields inaccurate estimates of oxygenation, while a careful selection of wavelengths in the 620-920nm range is likely to yield more accurate oxygenation values. We demonstrate that a 1D fluence correction obtained by fitting a linear function to the average decay rate in the image can further improve the estimates. However, opting to use these longer wavelengths involves sacrificing signal-to-noise ratio in the image, as the absorption of blood is low in this range. This results in an inherent trade-off between error in the sO2 estimates due to fluence variation and error due to noise. This study shows that the depth to which sO2 can be estimated accurately using a linear approximation is limited in vivo, even with idealised measurements, to at most 3mm. In practice, there will be even greater uncertainties affecting the estimates, e.g., due to bandlimited or partial-view acoustic detection.

  7. Sea surface: fate and biological effects of mixed contaminants

    SciTech Connect

    Hardy, J.T.; Crecelius, E.A.; Long, E.; Kiesser, S.L.; Stubin, A.I.; Gurtisen, J.M.; Apts, C.W.

    1985-09-01

    This research on the microlayer (upper 50 micrometers of the sea surface) confirms that many contaminants partition at this interface. High concentrations of polynuclear aromatic and chlorinated hydrocarbons were found in the microlayer of urban bays in Puget Sound. In some cases, concentrations exceeded water quality criteria by several orders of magnitude. At the same sites, subsurface bulk water showed no detectable contamination. Fertilized neustonic eggs of sand sole (Psettichthys melanostictus), were exposed to collected microlayer samples during their first week of embryonic and larval development. Compared to the rural site and/or central Puget Sound, exposure of embryos to microlayer from several urban bay sites resulted in delayed hatching, increased embryo mortality, and kyphosis (bent spine abnormalities) in hatched larvae. 28 refs., 2 figs., 4 tabs.

  8. 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

  9. 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.

  10. 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

  11. 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

  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. Acute toxicity, cytotoxicity, genotoxicity and antigenotoxic effects of a cellulosic exopolysaccharide obtained from sugarcane molasses.

    PubMed

    Pinto, Flávia Cristina Morone; De-Oliveira, Ana Cecília A X; De-Carvalho, Rosangela R; Gomes-Carneiro, Maria Regina; Coelho, Deise R; Lima, Salvador Vilar C; Paumgartten, Francisco José R; Aguiar, José Lamartine A

    2016-02-10

    The acute toxicity, cytotoxicity, genotoxicity and antigenotoxic effects of BC were studied. Cytotoxicity of BC was evaluated in cultured C3A hepatoma cells (HepG2/C3A) using a lactate dehydrogenase (LDH) activity assay. Acute toxicity was tested in adults Wistar rats treated with a single dose of BC. The genotoxicity of BC was evaluated in vivo by the micronucleus assay. BC (0.33-170 μg/mL) added to C3A cell culture medium caused no elevation in LDH release over the background level recorded in untreated cell wells. The treatment with the BC in a single oral dose (2000 mg/kg body weight) caused no deaths or signs of toxicity. BC attenuated CP-induced and inhibition the incidence of MNPCE (female: 46.94%; male: 22.7%) and increased the ratio of PCE/NCE (female: 46.10%; male: 35.25%). There was no alteration in the LDH release in the wells where C3A cells were treated with increasing concentrations of BC compared to the wells where the cells received the cell culture medium only (background of approximately 20% cell death), indicated that in the dose range tested BC was not cytotoxic. BC was not cytotoxic, genotoxic or acutely toxic. BC attenuated CP-induced genotoxic and myelotoxic effects. PMID:26686163

  14. Application of the SEA Directive to EU structural funds: Perspectives on effectiveness

    SciTech Connect

    Theophilou, Vassilia; Bond, Alan; Cashmore, Mat

    2010-02-15

    The European Union (EU) has two potentially conflicting policy goals: the Lisbon Agenda and the Cardiff process which, respectively, aim to make the EU most competitive and dynamic knowledge-based economy in the world, and integrate the environment into all EU policies. This research uses two case studies of Operational Programmes drawing on EU structural funds. Such programmes have recently been made subject to Strategic Environmental Assessment (SEA) under the EU SEA Directive, and allowed an assessment of the substantive (does it achieve its goals) and transactive (is it cost efficient) effectiveness of the SEA process, (i.e. does it support the Cardiff process or the Lisbon agenda?). Documentary review and interviews were the primary method drawing on actors involved both in the two case studies, and within the EU. The results indicate that transactive and substantive effectiveness are intrinsically linked and that both cases demonstrated some substantive effectiveness, but only one was transactively effective. Effectiveness was judged to be a function of design, procedure, substance as well as transaction, influenced by political issues. As with other research, we find that perspectives of effectiveness are very much driven by individual expectations, suggesting that a true measure of effectiveness might be the extent to which SEA can change expectations.

  15. 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.

  16. Effects of ultrasonic irradiation on the properties of coatings obtained by electroless plating and electro plating.

    PubMed

    Touyeras, F; Hihn, J Y; Bourgoin, X; Jacques, B; Hallez, L; Branger, V

    2005-01-01

    This paper deals with the effects of ultrasonic irradiation on electroless copper coating i.e. metallic deposition on non-conductive substrates and on electroplating on metallic substrates. Ultrasonic irradiation was both applied during activation (surface preparation for the electroless coating) and during plating steps in both cases. Several parameters were monitored, such as plating rates, practical adhesion, hardness, internal stress versus varying acoustic powers and frequencies. Optimum conditions for irradiation time, frequency and power were determined for each step. It appears clearly that ultrasound use affects deposit properties. Then, changes in the coating mechanisms can be discussed, and several parameters will be explored in this paper, to explain enhancement of deposit properties: increase in catalyst specific area, stirring dependence, surface energy evolution, dihydrogen desorption, structure of coating. PMID:15474947

  17. 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.

  18. 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

  19. 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.

  20. Effects of Gravity on Spicule Formation in Cultured Micromeres of Sea Urchin Embryo

    NASA Astrophysics Data System (ADS)

    Izumi-Kurotani, A.; Kiyomoto, M.; Eguchi, H.

    To investigate effect of gravity on morphogenesis at a cellular level, we propose a new experimental system with sea urchin embryos and micromeres. We studied the spicule formation in cultured micromeres of sea urchin embryo under various conditions of gravity; hypergravity by a centrifuge, simulated microgravity in a vertical clinostat, and alterations of the gravity force by a parabolic flight. Spicule elongation was suppressed under these experimental conditions. A spicule of sea urchin embryo consists of CaCO3 crystals in the form of calcite with magnesium and organic substances, called spicule matrix proteins. We also measured the level of expression of spicule matrix proteins by RT-PCR. The expression of a spicule matrix protein, SM30 was suppressed under hypergravity by a centrifuge and after a parabolic flight. These results suggest that each gravity condition can have an effect on the gene expression of spicule matrix protein.

  1. 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.

  2. 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.

  3. Effect of Erabu sea snake (Laticauda semifasciata) lipids on the swimming endurance of aged mice.

    PubMed

    Zhang, Guihua; Shirai, Nobuya; Higuchi, Tomoyuki; Suzuki, Hiramitsu; Shimizu, Eiji

    2007-12-01

    The effect of Erabu sea snake (Laticauda semifasciata) lipids on the swimming endurance was investigated in aged mice. Fifty three-week-old male Crlj:CD-1 (ICR) mice were fed one of three experimental diets containing either 6% lard, 6% fish oil, or 6% sea snake lipids for 16 wk. The swimming exercise was carried out in an acrylic plastic tank filled with 25 cm of water maintained at 23(o)C. Swimming times to exhaustion were measured with a load of 2% of their body weights attached to the tails of the mice. The swimming times to exhaustion of the group that were fed the sea snake lipid diet tended to be longer than those of the lard diet group, and were significantly improved compared with the fish oil diet group (p<0.05). The plasma and muscle lactate levels were significantly lower in the sea snake lipid diet group than in the lard and fish oil diet groups (p<0.05). The liver glycogen and plasma glucose levels of the sea snake lipid diet group did not differ markedly from those of the lard diet group (p>0.05), and were significantly higher than those of the fish oil diet group (p<0.05). These results suggest that an intake of sea snake lipids but not the fish oil, which is also rich in n-3 polyunsaturated fatty acids (n-3 PUFAs), is useful for improving the swimming endurance of aged mice by attenuating lactate production and/or enhancing lactate clearance during swimming exercise, and the n-3 PUFAs contained in the sea snake lipids did little or nothing for this improved endurance. PMID:18202534

  4. 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

  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. 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

  7. 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.

  8. 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.

  9. Salinization processes in an alluvial coastal lowland plain and effect of sea water level rise

    NASA Astrophysics Data System (ADS)

    Don, Nguyen Cao; Hang, Nguyen Thi Minh; Araki, Hiroyuki; Yamanishi, Hiroyuki; Koga, Kenichi

    2006-03-01

    In coastal areas, groundwater and aquifer systems are easily prone to pollution and contamination. Moreover, sea level rises also threaten the viability of many coastal zones and small islands. In the Shiroishi lowland plain, southwestern Kyushu Island of Japan, some environmental problems such as land subsidence and salinity intrusion due to over pumping of groundwater have long been recognized as water problems and become causes for public concern. In this study, an integrated surface and groundwater model was established and applied to the Shiroishi site to simulate groundwater flow hydraulics and predict the salinity intrusion process in the alluvial lowland plain. The simulated results show that groundwater levels in the aquifer greatly vary in response to varying climatic and pumping conditions. It is also found that sea water intrusion would be expected along the coast if the current rates of groundwater exploitation continue. Furthermore, sea water intrusion with a relative rise in sea water level due to aquifer compression and global climatic change was also considered. As a result, sea water intrusion appears to extend much farther in land from the coast compared to a reference case. The study also suggests a possible alternative to mitigate the inverse effects by pumping groundwater.

  10. 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.

  11. Effect on Intestinal Growth of the Population of Cellobiose-Oligosaccharides Obtained by Enzymatic Reaction with Dextransucrase

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although the synthesis of oligosaccharides obtained by reactions catalyzed by dextransucrase using sucrose as donor and different carbohydrates as acceptors has been widely studied, the effect of many of these carbohydrates in the growth of intestinal flora has not yet been evaluated. Such is the c...

  12. 29 CFR 500.4 - Effect of prior judgments and final orders obtained under the Farm Labor Contractor Registration...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Effect of prior judgments and final orders obtained under the Farm Labor Contractor Registration Act. 500.4 Section 500.4 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS MIGRANT AND SEASONAL AGRICULTURAL...

  13. 29 CFR 500.4 - Effect of prior judgments and final orders obtained under the Farm Labor Contractor Registration...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Effect of prior judgments and final orders obtained under the Farm Labor Contractor Registration Act. 500.4 Section 500.4 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS MIGRANT AND SEASONAL AGRICULTURAL...

  14. Short-term effects of polynuclear aromatic hydrocarbons on sea-surface microlayer phytoneuston

    SciTech Connect

    Riznyk, R.Z.; Hardy, J.T.; Pearson, W.; Jabs, L.

    1987-06-01

    The Puget Sound area, in the state of Washington, is characterized by an increasing population reflected by the growth of Seattle and Tacoma and their respective industrial-based economies. Previous work on the sea-surface microlayer of Puget Sound has shown that contaminant metals and organics are present at some sites at concentrations from 10 to more than 1000 times greater than in underlying sea water. Since the sea-surface microlayer may contain an inordinately high concentration of PAHs relative to the water column, the authors decided to investigated the short-term effect of these hydrophobic contaminants on phytoneuston community dynamics under controlled in situ conditions during this summer season when bloom conditions can prevail in areas of Puget Sound.

  15. 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.

  16. 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.

  17. 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

  18. Changes in nitrogen and phosphorus and their effects on phytoplankton in the Bohai Sea

    NASA Astrophysics Data System (ADS)

    Xu, Sisi; Song, Jinming; Li, Xuegang; Yuan, Huamao; Li, Ning; Duan, Liqin; Sun, Peiyan

    2010-07-01

    Systematic studies of the changes in dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP) and their effects on phytoplankton over the last 30 years in the Bohai Sea are presented. The amount of sewage disposal, use of fertilizer and the Huanghe River runoff were found to have a significant influence on the DIN or DIP concentrations in the Bohai Sea over the last 30 years. Moreover, the changes in DIN and DIP resulted in changes in the limiting nutrients of phytoplankton in the Bohai Sea from nitrogen in the early 1980s to nitrogen-phosphorus in the late 1980s, and then to phosphorus after the 1990s. In addition, changes in nitrogen and phosphorus had a significant effect on the phytoplankton community structure. The half saturation constant ( K s) was used to evaluate the effect of nutrients on the phytoplankton community structure in the Bohai Sea over the last 30 years. Cell abundance percentages of dominant phytoplankton species with high K s values for phosphorus and low K s values for nitrogen have decreased since the 1980s, while those of dominant phytoplankton species with low K s values for phosphorus and high K s values for nitrogen increased during this period.

  19. 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.

  20. 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

  1. 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

  2. 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.

  3. Effect of Organic Sea Spray Aerosol on Global and Regional Cloud Condensation Nuclei Concentrations

    NASA Astrophysics Data System (ADS)

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

    2009-12-01

    Physical processes on the ocean surface (bubble bursting) result in formation of sea spray aerosol. It is now recognized that this aerosol source includes a significant amount of organic matter (O’Dowd et al. 2004). Higher amounts of aerosol lead to higher cloud condensation nuclei (CCN) concentrations, which perturb climate by brightening clouds in what is known as the aerosol indirect effect (Twomey 1977). This work quantifies the marine organic aerosol global emission source as well the effect of the aerosol on CCN by implementing an organic sea spray source function into a series of global aerosol simulations. The new organic sea spray source function correlates satellite retrieved chlorophyll concentrations to fraction of organic matter in sea spray aerosol (O’Dowd et al. 2008). Using this source function, a global marine organic aerosol emission rate of 17.2 Tg C yr-1 is estimated. Effect on CCN concentrations (0.2% supersaturation) is modeled using the Two-Moment Aerosol Sectional (TOMAS) microphysics algorithm coupled to a general circulation model (Adams and Seinfeld 2002). Upon including organic sea spray aerosol in global simulations, changes in CCN concentrations are induced by the changed aerosol composition as well as the ability of the organic matter to serve as surfactants. To explore surfactant effects, surface tension depression data from seawater samples taken near the Georgia coast were applied as a function of carbon concentrations (Moore et al. 2008). Preliminary findings suggest that organic sea spray aerosol exerts a localized influence on CCN(0.2%) concentrations. Surfactant effects appear to be the most important impact of marine organic aerosol on CCN(0.2%), as changes in aerosol composition alone have a weak influence, even in regions of high organic sea spray emissions. 1. O’Dowd, C.D., Facchini, M.C. et al., Nature, 431, (2004) 2. Twomey, S., J. Atmos. Sci., 34, (1977) 3. O’Dowd C.D et al. Geophys. Res. Let., 35, (2008) 4

  4. 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

  5. Accumulations of total metal in dominant shrimp species (Palaemon adspersus, Palaemon serratus, Parapenaeus longirostris) and bottom surface sediments obtained from the Northern Inner Shelf of the Sea of Marmara.

    PubMed

    Kurun, A; Balkis, H; Balkis, N

    2007-12-01

    The aim of this study is to determine the total metal (aluminum, copper, manganese, nickel, lead, zinc, cadmium, iron, mercury) contents of dominant shrimp species and sediments present at 1-50 m depths of the Northern Inner Shelf of the Sea of Marmara. Shrimp and sediment samples were collected from four regions (Büyükçekmece, Silivri, Tekirdağ, Sarköy) and from different depths (1, 5, 10, 20, 30, 50 m) at each region in September and November of 2003. Three shrimp species [Palaemon adspersus (Rathke, 1937), Palaemon serratus (Pennant, 1777), Parapenaeus longirostris (H. Lucas, 1846)] were identified to be dominant as a result of the examination on the obtained samples. Heavy metal contents of these three species were determined and the results were compared with the acceptable treshold values of the Seafood Standards and also with available literatures. The Cu contents were found to be higher than the treshold limits in all samples except P. longirostris from Silivri, also the Cd contents in all samples except P. adspersus from Büyükçekmece, the Zn contents only in P. adspersus and P. longirostris from Tekirdağ, and the Pb contents in all species from all regions. These high values are the indicator of industrial pollution. There is not any data in the Seafood Standards about Mn, Ni, Fe and Al contents in shrimp species. The values of these metal contents were given in the present study. The examination of total metal distributions in bottom surface sediment samples in the Northern Inner Shelf of the Sea of Marmara showed that the determined values were higher than the shale average at some depths of examined stations. PMID:17406997

  6. 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

  7. 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.

  8. Assessing the effects of changing demographic and consumption patterns on sea tenure regimes in the Roviana Lagoon, Solomon Islands.

    PubMed

    Aswani, Shankar

    2002-06-01

    This paper investigates how sea tenure institutions in the Roviana Lagoon, Solomon Islands, mediate among population, consumption, and the environment. The focus is on explaining how growth in population and consumption alter sea tenure regimes, and the factors that shape either their institutional robustness or vulnerability. The paper also addresses the regional differences among sea tenure institutional arrangements, the processes that are producing them, and the social and environmental outcomes of these institutions as they engage external forces and internal changes. A major question is how existing forms of sea tenure respond comparatively when faced with parallel demographic and economic transformations? Two villages representing different sea tenure arrangements within the Roviana Lagoon are compared. Results show that inhabitants in these villages perceive their systems of sea tenure governance similarly; yet their managerial responses to changes brought about by growth in population and consumption differ, and the responses produce contrasting environmental effects. PMID:12174597

  9. 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.

  10. Winter meso-scale shear front in the Yellow Sea and its sedimentary effects

    NASA Astrophysics Data System (ADS)

    Gao, Fei; Qiao, Lulu; Li, Guangxue

    2016-02-01

    In this paper, the authors explored the presence of shear fronts between the Yellow Sea Coastal Current (YSCC) and the monsoon-strengthened Yellow Sea Warm Current (YSWC) in winter and their sedimentary effects within the shear zone based on a fully validated numerical model. This work added the wind force to a tidal model during simulating the winter baroclinic circulation in the Yellow Sea. The results indicate that the YSWC is significantly strengthened by wind-driven compensation due to a northeast monsoon during winter time. When this warm current encounters the North Shandong-South Yellow Sea coastal current, there is a strong reverse shear action between the two current systems, forming a reverse-S-shaped shear front that begins near 34°N in the south and extends to approximately 38°N, with an overall length of over 600 km. The main driving force for the formation of this shear front derives from the circulation system with the reverse flow. In the shear zone, temperature and salinity gradients increase, flow velocities are relatively small and the flow direction on one side of the shear zone is opposite to that on the other side. The vertical circulation structure is complicated, consisting of a series of meso- and small-scale anti-clockwise eddies. Particularly, this shear effect significantly hinders the horizontal exchange of coastal sediments carried by warm currents, resulting in fine sediments deposition due to the weak hydrodynamic regime.

  11. Thermodynamical effects accompanied freezing of two water layers separated by sea ice sheet

    NASA Astrophysics Data System (ADS)

    Bogorodsky, Petr; Marchenko, Aleksey

    2014-05-01

    The process of melt pond freezing is very important for generation of sea ice cover thermodynamic and mass balance during winterperiod. However, due to significant difficulties of field measurements the available data of model estimations still have no instrumental confirmation. In May 2009 the authors carried out laboratory experiment on freezing of limited water volume in the University Centre in Svalbard ice tank. In the course of experiment fresh water layer of 27.5 cm thickness at freezing point poured on the 24 cm sea ice layer was cooled during 50 hours at the temperature -10º C and then once again during 60 hours at -20º C. For revealing process typical characteristics the data of continuous measurements of temperature and salinity in different phases were compared with data of numerical computations obtained with thermodynamic model which was formulated in the frames of 1-D equation system (infinite extension of water freezing layer) and adapted to laboratory conditions. The known surprise of the experiment became proximity of calculated and measured estimates of process dynamics that confirmed the adequacy of the problem mathematical statement (excluding probably process finale stage). This effect can be explained by formation of cracks on the upper layer of ice at sharp decreases of air temperature, which temporary compensated hydrostatic pressure growth during freezing of closed water volume. Another compensated mechanism can be migration of brine through the lower layer of ice under influence of vertical pressure gradient and also rejection of gas dissolved in water which increased its compressibility. During 110 hours cooling thickness of water layer between ice layers reduced approximately to 2 cm. According to computations this layer is not chilled completely but keeps as thin brine interlayer within ice body whose thickness (about units of mm) is determined by temperature fluctuations of cooled surface. Nevertheless, despite good coincidence of

  12. Effective sea-level rise and deltas: Causes of change and human dimension implications

    NASA Astrophysics Data System (ADS)

    Ericson, Jason P.; Vörösmarty, Charles J.; Dingman, S. Lawrence; Ward, Larry G.; Meybeck, Michel

    2006-02-01

    An assessment is made of contemporary effective sea-level rise (ESLR) for a sample of 40 deltas distributed worldwide. For any delta, ESLR is a net rate, defined by the combination of eustatic sea-level rise, the natural gross rate of fluvial sediment deposition and subsidence, and accelerated subsidence due to groundwater and hydrocarbon extraction. ESLR is estimated under present conditions using a digital data set of delta boundaries and a simple model of delta dynamics. The deltas in this study represent all major climate zones, levels of population density, and degrees of economic development. Collectively, the sampled deltas serve as the endpoint for river basins draining 30% of the Earth's landmass, and 42% of global terrestrial runoff. Nearly 300 million people inhabit these deltas. For the contemporary baseline, ESLR estimates range from 0.5 to 12.5 mm yr - 1 . Decreased accretion of fluvial sediment resulting from upstream siltation of artificial impoundments and consumptive losses of runoff from irrigation are the primary determinants of ESLR in nearly 70% of the deltas. Approximately 20% of the deltas show accelerated subsidence, while only 12% show eustatic sea-level rise as the predominant effect. Extrapolating contemporary rates of ESLR through 2050 reveals that 8.7 million people and 28,000 km 2 of deltaic area in the sample set of deltas could suffer from enhanced inundation and increased coastal erosion. The population and area inundated rise significantly when considering increased flood risk due to storm surge. This study finds that direct anthropogenic effects determine ESLR in the majority of deltas studied, with a relatively less important role for eustatic sea-level rise. Serious challenges to human occupancy of deltaic regions worldwide are thus conveyed by factors which to date have been studied less comprehensively than the climate change-sea-level rise question.

  13. 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

  14. 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. PMID:25435066

  15. 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.

  16. 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...

  17. 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.

  18. 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. PMID:25890051

  19. [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

  20. 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.

  1. 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.

  2. Seasonal inhibitory effects of marine plants on sea urchins: structuring communities the algal way.

    PubMed

    Konar, B

    2000-10-01

    Natural and manipulative experiments were used to evaluate the effect of algal cover on sea urchin (Strongylocentrotus polyacanthus) distribution on submarine pinnacles at Shemya Island in the western Aleutian Archipelago. In July, pinnacle tops had dense kelp stands with low densities of sea urchins. In subsequent months, urchin densities increased as annual algal cover declined. In the summer, removal of specific combinations of macroalgae from the pinnacle tops resulted in an increase in urchin density. Artificial structures that imitated certain common seaweeds were placed on pinnacle tops and inhibited urchin movement. Clod cards that were used to measure relative abrasion rates on vegetated and cleared pinnacles demonstrated that algae cause a significant amount of abrasion. This study showed that the physical structure of the dominant annual alga, Desmarestia viridis, is capable of limiting sea urchin distribution, movement, and grazing. In this study, a potential food source actively controlled herbivore distribution and was the primary cause for the persistence of isolated kelp communities surrounded by barrens dominated by sea urchin grazing. PMID:24595832

  3. 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.

  4. 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

  5. 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.

  6. Vasorelaxant activity of extracts obtained from Apium graveolens: Possible source for vasorelaxant molecules isolation with potential antihypertensive effect

    PubMed Central

    Jorge, Vergara-Galicia; Ángel, Jimenez-Ramirez Luis; Adrián, Tun-Suarez; Francisco, Aguirre-Crespo; Anuar, Salazar-Gómez; Samuel, Estrada-Soto; Ángel, Sierra-Ovando; Emmanuel, Hernandez-Nuñez

    2013-01-01

    Objective To investigate vasorelaxant effect of organic extracts from Apium graveolens (A. graveolens) which is a part of a group of plants subjected to pharmacological and phytochemical study with the purpose of offering it as an ideal source for obtaining lead compounds for designing new therapeutic agents with potential vasorelaxant and antihypertensive effects. Methods An ex vivo method was employed to assess the vasorelaxant activity. This consisted of using rat aortic rings with and without endothelium precontracted with norepinephrine. Results All extracts caused concentration-dependent relaxation in precontracted aortic rings with and without endothelium; the most active extracts were Dichloromethane and Ethyl Acetate extracts from A. graveolens. These results suggested that secondary metabolites responsible for the vasorelaxant activity belong to a group of compounds of medium polarity. Also, our evidence showed that effect induced by dichloromethane and ethyl acetate extracts from A. graveolens is mediated probably by calcium antagonism. Conclusions A. graveolens represents an ideal source for obtaining lead compounds for designing new therapeutic agents with potential vasorelaxant and antihypertensive effects. PMID:24075341

  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. 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

  9. 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

  10. An exact method to obtain effective electrostatic interactions from computer simulations: The case of effective charge amplification

    NASA Astrophysics Data System (ADS)

    González-Mozuelos, P.; Guerrero-García, G. I.; Olvera de la Cruz, M.

    2013-08-01

    We discuss here an exact method to determine the parameters regulating the screened Coulomb interactions among spherical macroions immersed in a simple electrolyte. This approach provides rigorous definitions for the corresponding screening length, effective permittivity, and renormalized charges, and can be employed for precise and reliable calculations of these parameters within any scheme. In particular, we introduce a simple procedure for extracting this information from computer simulations. The viability of this approach is demonstrated by applying it to a three-component model system which includes anionic nanoparticles and monovalent cations and anions. The mean forces between nanoparticles are determined directly from simulations with two macroions, plus small ions, inside a single cell with periodic boundary conditions. The values of the parameters of interest, on the other hand, are gathered from two separate sets of computer simulations: one set provides information about the short-range correlations among the small ions, which in turn determine the screening length and effective permittivity; the second set supplies the short-range components of the ionic distribution around one isolated macroion, which also determine its renormalized charge. The method presented here thus avoids the uncertain fitting of these parameters from the asymptotic tail of the mean force and allows us to investigate in detail this connection between the renormalized charge of the macroion and the short-range (virtual) part of the ionic cloud surrounding it. Using the standard prescription to extract an effective charge from the corresponding renormalized value, we then proceed to clarify the mechanisms behind the possibility of effective charge amplification (i.e., an effective charge larger than the bare macroion charge). Complementarily, we report results for the corresponding bridge functions too.

  11. New fitting scheme to obtain effective potential from Car-Parrinello molecular-dynamics simulations: Application to silica

    NASA Astrophysics Data System (ADS)

    Carré, A.; Horbach, J.; Ispas, S.; Kob, W.

    2008-04-01

    A fitting scheme is proposed to obtain effective potentials from Car-Parrinello molecular-dynamics (CPMD) simulations. It is used to parameterize a new pair potential for silica. MD simulations with this new potential are done to determine structural and dynamic properties and to compare these properties to those obtained from CPMD and a MD simulation using the so-called BKS potential. The new potential reproduces accurately the liquid structure generated by the CPMD trajectories, the experimental activation energies for the self-diffusion constants and the experimental density of amorphous silica. Also lattice parameters and elastic constants of α-quartz are well reproduced, showing the transferability of the new potential.

  12. 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.

  13. 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

  14. 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.

  15. 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. PMID:22088015

  16. Natural Weathering and Sea Water Effects on the Durability of Glass Fiber Reinforced Vinylester: Fractographic Analysis

    NASA Astrophysics Data System (ADS)

    Merah, Nesar; Nizamuddin, Seyed; Khan, Zafarullah; Al-Sulaiman, Faleh; Mehdi, Moeid

    2010-10-01

    This paper presents a study of the effects of harsh outdoor weather and warm sea water on the tensile behavior of Glass-Fiber Reinforced Vinylester (GFRV) pipe materials destined for sea water handling and transportation. The effect of Dhahran’s outdoor weather for exposure periods ranging from 3 to 36 months revealed an improvement in tensile strength when compared with the as received GFRV sample. A significant increasing trend of tensile strength from 3 to 12 months was noted. This is attributed mainly to the post curing effects resulting in higher cross linking density. After 12 months of exposure the tensile strength showed a decreasing trend, but remaining still higher than the average tensile strength of as received (baseline) GFRV sample. Similar results of enhanced tensile strength were noted after immersion of GFRV pipes in warm Gulf sea water for 12 months. Fractographic analysis was performed on the tensile tested GFRV samples using optical microscope followed by scanning electron microscope (SEM). The characterization of the controlling failure mechanisms involved from fracture initiation to fracture propagation through the gage section of the specimen were predicted and were justified by correlating the optical and SEM pictures.

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

    NASA Astrophysics Data System (ADS)

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

    2009-01-01

    We report an investigation of the effects of increases in pCO2 on the 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 rate 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 expression of the hsp70 gene. However, there was a consistent and significant increase in the expression of the gapdh gene at a pH of ~7.5 which indicated a possible disruption to oxidative metabolic processes. It was concluded that future predicted changes in sea water pH may have subtle effects on the physiology and metabolism of coastal and marine species which may be overlooked in studies of whole organism response.

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

    NASA Astrophysics Data System (ADS)

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

    2015-06-01

    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.

  19. 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.

  20. Effects of irregular sea surface and evaporation duct on radar detection performance

    NASA Astrophysics Data System (ADS)

    Marom, Moshe

    1988-06-01

    The detection performance of microwave search radars operating in close proximity to the sea surface is evaluated. The effects of media characteristics on the propagation of electromagnetic waves have been incorporated. Specular and diffused scattering from a rough surface, and the effects of the curvature of the earth's surface have been included in the study. Additionally, surface ducting effects caused by atmospheric anomalies are presented. Some design and operational considerations which can improve the detection performance of a surface search radar, are also presented.

  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. PMID:27137234

  2. 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

  3. 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

  4. 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.

  5. 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.

  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. 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.

  9. 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.

  10. Transequatorial effects of sea surface temperature anomalies in a global general circulation model

    NASA Technical Reports Server (NTRS)

    Spar, J.

    1972-01-01

    The global response of the atmosphere to a persistent anomalous pool of warm sea surface temperatures in the extratropical Pacific Ocean is examined in terms of the meridional pole-to-pole profile of the zonally-averaged 600 mb surface for periods up to 90 days. Following an initial hydrostatic inflation of the isobaric surface in the latitude of the warm pool, effects spread poleward within the hemisphere, then begin to appear after about two to three weeks in high latitudes of the opposite hemisphere, but with little or no response in the tropics. The same sea temperature anomaly field generates a stronger response in winter than in summer, and a very different reaction when located in the Southern Hemisphere than when in the Northern Hemisphere.

  11. 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.

  12. 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

  13. 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

  14. Metabolic Effects of Insulin and IGFs on Gilthead Sea Bream (Sparus aurata) Muscle Cells

    PubMed Central

    Montserrat, Núria; Capilla, Encarnación; Navarro, Isabel; Gutiérrez, Joaquim

    2012-01-01

    Primary cultures of gilthead sea bream myocytes were performed in order to examine the relative metabolic function of insulin compared with IGF-I and IGF-II (insulin-like growth factors, IGFs) at different stages in the cell culture. In these cells, the in vitro effects of insulin and IGFs on 2-deoxyglucose (2-DG) and l-alanine uptake were studied in both myocytes (day 4) and small myotubes (day 9). 2-DG uptake in gilthead sea bream muscle cells was increased in the presence of insulin and IGFs in a time dependent manner and along with muscle cell differentiation. On the contrary, l-alanine uptake was also stimulated by insulin and IGFs but showed an inverse pattern, being the uptake higher in small myocytes than in large myotubes. The results of preincubation with inhibitors (PD-98059, wortmannin, and cytochalasin B) on 2-DG uptake indicated that insulin and IGFs stimulate glucose uptake through the same mechanisms, and evidenced that mitogenesis activator protein kinase (MAPK) and PI3K–Akt transduction pathways mediate the metabolic function of these peptides. In the same way, we observed that GLUT4 protein synthesis was stimulated in the presence of insulin and IGFs in gilthead sea bream muscle cells in a different manner at days 4 or 9 of the culture. In summary we describe here, for the first time, the effects of insulin and IGFs on 2-DG and l-alanine uptake in primary culture of gilthead sea bream muscle cells. We show that both MAPK and PI3K–Akt transduction pathways are needed in order to control insulin and IGFs actions in these cells. Moreover, changes in glucose uptake can be explained by the action of the GLUT4 transporter, which is stimulated in the presence of insulin and IGFs throughout the cell culture. PMID:22654873

  15. Direct and indirect effects of sea spray geoengineering and the role of injected particle size

    NASA Astrophysics Data System (ADS)

    Partanen, Antti-Ilari; Kokkola, Harri; Romakkaniemi, Sami; Kerminen, Veli-Matti; Lehtinen, Kari E. J.; Bergman, Tommi; Arola, Antti; Korhonen, Hannele

    2012-01-01

    Climate-aerosol model ECHAM5.5-HAM2 was used to investigate how geoengineering with artificial sea salt emissions would affect marine clouds and the Earth's radiative balance. Prognostic cloud droplet number concentration and interaction of aerosol particles with clouds and radiation were calculated explicitly, thus making this the first time that aerosol direct effects of sea spray geoengineering are considered. When a wind speed dependent baseline geoengineering flux was applied over all oceans (total annual emissions 443.9 Tg), we predicted a radiative flux perturbation (RFP) of -5.1 W m-2, which is enough to counteract warming from doubled CO2 concentration. When the baseline flux was limited to three persistent stratocumulus regions (3.3% of Earth's surface, total annual emissions 20.6 Tg), the RFP was -0.8 Wm-2 resulting mainly from a 74-80% increase in cloud droplet number concentration and a 2.5-4.4 percentage point increase in cloud cover. Multiplying the baseline mass flux by 5 or reducing the injected particle size from 250 to 100 nm had comparable effects on the geoengineering efficiency with RFPs -2.2 and -2.1 Wm-2, respectively. Within regions characterized with persistent stratocumulus decks, practically all of the radiative effect originated from aerosol indirect effects. However, when all oceanic regions were seeded, the direct effect with the baseline flux was globally about 29% of the total radiative effect. Together with previous studies, our results indicate that there are still large uncertainties associated with the sea spray geoengineering efficiency due to variations in e.g., background aerosol concentration, updraft velocity, cloud altitude and onset of precipitation.

  16. 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.

  17. 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.

  18. 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

  19. The meteorological effects on microwave apparent temperatures looking downward over a smooth sea

    NASA Technical Reports Server (NTRS)

    Wu, S.

    1973-01-01

    The effects of clouds and rain on microwave apparent temperatures for a flat sea surface are examined. The presence of clouds and rain can be expressed as a change of absorption coefficient and the total absorption is computed as the sum of individual effects. Various cloud and rain models proposed by meteorologists are employed to compute the microwave apparent temperature when viewing downward through these model atmospheres. It is shown that stratus, cumulus, overcast, and rain all contribute significantly to the observed temperature. Larger sensitivities to clouds and rain are observed for horizontally polarized apparent temperature at large nadir angles than for vertically polarized apparent temperature.

  20. The cloud cover fraction obtained from a ground CCD camera and its effect on a radiative transfer model

    NASA Astrophysics Data System (ADS)

    Souza, M. P.; Pereira, E. B.; Martins, F. R.; Chagas, R. C.; Freitas, W. S., Jr.

    2003-04-01

    Clouds are the major factor that rules the solar irradiance over Earth's surface. They interact with solar radiation in the shortwave spectra and with terrestrial radiation emitted by Earth's surface in the longwave range. Information about cloud cover is a very important input data for radiative transfer models and great effort is being made to improve methods to get this information. This paper reports the effects on a radiative transfer model by using the simple cloud fraction obtained by a ground set CCD camera instead of the satellite derived cloud index. The BRASIL-SR model is a radiative transfer model that calculates surface solar irradiance, using a normalized cloud index determined by statistical analyses of satellites images and from climatological values of temperature and albedo. Cloud fraction was obtained from digital images collected by a ground set CCD (Charge Coupled Device) camera, in the visible range (0.4mm - 0.7mm) as RGB (Red - Green - Blue) compositions. The method initially transforms the image attributes from the RGB space to the IHS (Intensity - Hue - Saturation) space. The algorithm defines threshold values for the saturation component of the IHS system to classify a pixel as cloudy or clear sky. Clear skies are identified by high values of saturation in the visible range while cloudy condition presents a mixture of several wavelengths and consequently lower saturation values. Results from the CCD camera and from the satellite were compared with the Kt and Kd from pyranometer data obtained from a local BSRN radiation station at Florianópolis (27º 28'S, 48º 29'W) and show that cloud fraction is only a poor information about the cloud sky status since it does not bear any information on the cloud optical depth which is needed in most radiative transfer models such as the one used in this paper (the BRASIL-SR).

  1. 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

  2. The effects of porosity on optical properties of semiconductor chalcogenide films obtained by the chemical bath deposition

    PubMed Central

    2012-01-01

    This paper is dedicated to study the thin polycrystalline films of semiconductor chalcogenide materials (CdS, CdSe, and PbS) obtained by ammonia-free chemical bath deposition. The obtained material is of polycrystalline nature with crystallite of a size that, from a general point of view, should not result in any noticeable quantum confinement. Nevertheless, we were able to observe blueshift of the fundamental absorption edge and reduced refractive index in comparison with the corresponding bulk materials. Both effects are attributed to the material porosity which is a typical feature of chemical bath deposition technique. The blueshift is caused by quantum confinement in pores, whereas the refractive index variation is the evident result of the density reduction. Quantum mechanical description of the nanopores in semiconductor is given based on the application of even mirror boundary conditions for the solution of the Schrödinger equation; the results of calculations give a reasonable explanation of the experimental data. PMID:22931255

  3. Basis set effects on the intermolecular interaction energies of methane dimers obtained by the Moeller-Plesset perturbation theory calculation

    SciTech Connect

    Tsuzuki, Seiji; Tanabe, Kazutoshi )

    1991-03-21

    Intermolecular interaction energies of methane dimer were calculated by using several basis sets up to 6-311G(3d,4p) with electron correlation energy correction by the Moeller-Plesset perturbation method and basis set superposition error (BSSE) correction by the counterpoise method to evaluate the basis set effect. The calculated interaction energies depended on the basis set considerably. Whereas the interaction energies of repulsive component calculated at HF level were not affected by the change of basis set, the dispersion energy component dependent greatly on the basis set used. The dispersion energies calculated with the Moeller-Plesset second- and third-order perturbation by using 6-311G(2d,2p) basis set were 0-10% and 4-6% smaller than those obtained with the fourth-order (MP4(SDTQ)) perturbation, respectively. The BSSE's calculated by the counterpoise method were still about 30% of the calculated intermolecular interaction energies for the conformers of energy minima event at the MP4(SDTQ)/6-311G(2d,2p) level. The calculated interaction potentials of dimers at the MP4(SDTQ)/6-311G(2d,2p) level were considerably shallower than those obtained by MM2 force fields but were close to the potentials given by the Williams potential and by the recently reported MM3 force field.

  4. Effect of hyaluronan on developmental competence and quality of oocytes and obtained blastocysts from in vitro maturation of bovine oocytes.

    PubMed

    Opiela, Jolanta; Romanek, Joanna; Lipiński, Daniel; Smorąg, Zdzisław

    2014-01-01

    The objective of the present study was to evaluate the effect of hyaluronan (HA) during IVM on meiotic maturation, embryonic development, and the quality of oocytes, granulosa cells (GC), and obtained blastocysts. COCs were matured in vitro in control medium and medium with additional 0.035% or 0.07% of exogenous HA. The meiotic maturity did not differ between the analysed groups. The best rate and the highest quality of obtained blastocysts were observed when 0.07% HA was used. A highly significant difference (P < 0.001) was noted in the mean number of apoptotic nuclei per blastocyst and in the DCI between the 0.07% HA and the control blastocysts (P < 0.01). Our results suggest that addition of 0.035% HA and 0.07% HA to oocyte maturation media does not affect oocyte nuclear maturation and DNA fragmentation. However, the addition of 0.07% HA during IVM decreases the level of blastocysts DNA fragmentation. Finally, our results suggest that it may be risky to increase the HA concentration during IVM above 0.07% as we found significantly higher Bax mRNA expression levels in GC cultured with 0.07% HA. The final concentration of HA being supplemented to oocyte maturation media is critical for the success of the IVP procedure. PMID:24689043

  5. 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

  6. 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.

  7. Relativistically corrected geometries obtained with analytical gradients: normalized elimination of the small component using an effective potential

    NASA Astrophysics Data System (ADS)

    Filatov, Michael; Cremer, Dieter

    2003-03-01

    For the quasi-relativistic normalized elimination of small component using an effective potential (NESC-EP) method, analytical energy gradients were developed, programmed, and implemented in a standard quantum chemical program package. NESC-EP with analytical gradients was applied to determine geometry, vibrational frequencies, and dissociation enthalpies of ferrocene, tungsten hexafluoride, and tungsten hexacarbonyle. Contrary to non-relativistic calculations and calculations carried out with RECPs for the same compounds, NESC-EP provided reliable molecular properties in good agreement with experiment. The computational power of NESC-EP results from the fact that reliable relativistic corrections are obtained at a cost level only slightly larger than that of a non-relativistic calculation.

  8. [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

  9. 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. PMID:26318566

  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. 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.

  12. 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. PMID:23638005

  13. Combined Effects of the North Atlantic Oscillation and the Arctic Oscillation on Sea Surface Temperature in the Alborán Sea

    PubMed Central

    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. PMID:23638005

  14. 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.

  15. 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.

  16. 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.

  17. Effects of deep-water coral banks on the abundance and size structure of the megafauna in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    D'Onghia, G.; Maiorano, P.; Sion, L.; Giove, A.; Capezzuto, F.; Carlucci, R.; Tursi, A.

    2010-03-01

    The Santa Maria di Leuca (SML) coral banks represent a rare example of living Lophelia-Madrepora-bearing coral mounds in the Mediterranean Sea. They are located between 350 and 1100 m in depth, in the northern Ionian Sea (eastern-central Mediterranean). Using a multi-beam echo sounder, side-scan sonar, high-resolution seismics and underwater video, the zones were identified for the sampling demersal fauna without damaging the coral colonies. During September-October 2005 experimental samplings were carried out with longlines and trawl nets inside the coral habitat and outside, where fishery exploitation occurs. No significant differences were shown between the abundance of fish recorded using longlines in the coral and non-coral habitat even though some selachians and teleosts were more abundant in the former than in the latter. Large specimens of rockfish ( Helicolenus dactylopterus) and blackspot seabream ( Pagellus bogaraveo) were commonly caught using longlines in the coral habitat. Data from trawling revealed refuge effects in the coral habitat and fishing effects outside. Significant differences were detected between the recorded abundances in the two study areas. Greater densities and biomasses were obtained inside the coral area, and fish size spectra and size distributions indicate a greater abundance of large fish inside the coral habitat. The SML coral habitat is a spawning area for H. dactylopterus. The remarkable density of the young-of-the-year of the deep-water shark Etmopterus spinax as well as of Merluccius merluccius, Micromesistius poutassou, Phycis blennoides and H. dactylopterus, indicates that the coral habitat also acts as nursery area for these demersal species, which are exploited outside. Considering the evidence of the negative impact of bottom trawling and, to a lesser extent, of longlining, the coral banks can provide a refuge for the conservation of unique species and habitats as well as in providing benefit to adjacent fisheries

  18. 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

  19. Effects of the North Atlantic Oscillation on sea ice breeding habitats of harp seals ( Pagophilus groenlandicus) across the North Atlantic

    NASA Astrophysics Data System (ADS)

    Friedlaender, Ari S.; Johnston, David W.; Halpin, Patrick N.

    2010-07-01

    Harp seals ( Pagophilus groenlandicus) are an abundant and commercially exploited species of phocid seal in the North Atlantic. Harp seals are entirely dependent on annual sea ice for breeding purposes and the distribution, abundance, and constitution of sea ice in this region are subject to tremendous interannual variability. As such, harp seal population dynamics are likely intimately tied to climate variability and global change. We used satellite-derived images of sea ice cover to determine trends in available habitat at the four major harp seal breeding areas in the North Atlantic, and assessed linkages amongst sea ice conditions and variability in the North Atlantic Oscillation (NAO) during 1978-2006. The White Sea breeding area had the highest annual ice concentrations, while the Gulf of St. Lawrence and Front regions were the most variable over time. We confirmed a consistent positive correlation between the NAO index and the amount of sea ice cover in Western North Atlantic breeding areas off Canada. Furthermore, we found an opposite and consistent negative correlation between the NAO and sea ice cover in the eastern-most breeding areas, leading to an out-of-phase signal between the Western and Eastern (particularly the White Sea) North Atlantic. These results indicate that sea ice dynamics in the breeding regions of harp seals are controlled, to some extent, by the phase of the NAO and its effects on weather across the North Atlantic. Previous studies indicate that poor ice conditions can have negative effects on harp seal survival and the consistent relationships between breeding habitat and NAO conditions that are described here have implications for both the biology and management of harp seal populations.

  20. 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

  1. 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

  2. Effect of different organic farming methods on the phenolic composition of sea buckthorn berries.

    PubMed

    Heinäaho, Merja; Hagerman, Ann E; Julkunen-Tiitto, Riitta

    2009-03-11

    The effects of different organic cultivation methods on the berry phenolics of two Finnish sea buckthorn (Hippophae rhamnoides L. ssp. rhamnoides ) cultivars, 'Terhi' and 'Tytti', were studied in an experimental field at a coastal area in Merikarvia, western Finland. Cultivation methods included different fertilizers (designed for organic cultivation), mulches (organic and plastic), and land contours (flat land versus ridged beds). Two experiments were conducted: The first, a fertilization experiment, allowed for the estimation of the effects of cultivar, fertilizer, land contour, and all of their interactions. The second experiment, a mulch experiment, allowed for the estimation of the effects of mulch, land contours, and their interactions for the cultivar 'Tytti'. Berry phenolics were analyzed by high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection. The results suggest that there are significant differences between the cultivars and cultivation methods. The concentrations of quercetin derivatives 1-3, isorhamnetin 3,7-diglucoside, quercetin-3-glucoside-7-rhamnoside, quercetin 3-glucoside, isorhamnetin 3-glucoside, and flavonoid derivative 3 were higher in 'Tytti' than in 'Terhi', while concentrations of isorhamnetin-glucoside 2 and 3 were higher in 'Terhi' than in 'Tytti'. Flat land increased the concentrations of isorhamnetin 3,7-diglucoside, isorhamnetin-glucoside 1, quercetin derivatives 2 and 4, and condensed tannins. Mulch did not have any significant effect on the concentrations of phenolic compounds. These results indicate that the phenolic accumulation in berries of studied sea buckthorn cultivars seems to be mainly dependent upon cultivar selection and soil structure. PMID:19219991

  3. 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.

  4. Effects of Kuroshio intrusions on nonlinear internal waves in the South China Sea during winter

    NASA Astrophysics Data System (ADS)

    Park, Jae-Hun; Farmer, David

    2013-12-01

    During winter the Kuroshio tends to cross Luzon Strait, penetrating the northeastern South China Sea where it forms energetic mesoscale structures. Luzon Strait is also a site where westward-propagating large-amplitude internal waves are generated. We describe observations of these waves acquired in the deep basin of the South China Sea during the winter of 2010-2011, with the goal of assessing the influence of mesoscale variability on their properties. Combining tidal current simulations with an internal wave generation and evolution model, we obtain time series of deviations between our observations and the model simulations. These deviations are analyzed in terms of mesoscale variability based on the data-assimilated HYbrid Coordinate Ocean Model (HYCOM) simulations. We find that simplified models of nonlinear internal wave response to changes in horizontal stratification gradients and vertical shear provide at best weak simulations of amplitude modulation. In contrast to these results, deviations of internal wave arrival time, occurring up to 2 h early during Kuroshio inflows, are quite well simulated when derived from integration of the first internal mode phase speed along two-dimensional ray-traced paths using HYCOM simulations of velocity and density fields together with bathymetry. Refraction of the internal waves by Kuroshio intrusions can lead to substantial distortion of the paths, sufficient to provide a potential explanation for the apparent suppression of waves during previous winter measurements. Our results suggest that the internal wave field can be a sensitive indicator of mesoscale variability in Luzon Strait and the northeastern South China Sea.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. In silico assessment of adverse effects of a large set of 6-fluoroquinolones obtained from a study of tuberculosis chemotherapy.

    PubMed

    Tusar, Marjan; Minovski, Nikola; Fjodorova, Natalja; Novic, Marjana

    2012-09-01

    Among the different chemotherapeutic classes available today, the 6-fluoroquinolone (6-FQ) antibacterials are still one of the most effective cures in fighting tuberculosis (TB). Nowadays, the development of novel 6-FQs for treatment of TB mainly depends on understanding how the structural modifications of the main quinolone scaffold at specific positions affect the anti-mycobacterial activity. Alongside the structure-activity relationship (SAR) studies of the 6-FQ antibacterials, which can be considered as a golden rule in the development of novel active antitubercular 6-FQs, the structure side effects relationship (SSER) of these drugs must be also taken into account. In the present study we focus on a proficient implementation of the existing knowledge-based expert systems for design of novel 6-FQ antibacterials with possible enhanced biological activity against Mycobaterium tuberculosis as well as lower toxicity. Following the SAR in silico studies of the quinolone antibacterials against M. tuberculosis performed in our laboratory, a large set of 6-FQs was selected. Several new 6-FQ derivatives were proposed as drug candidates for further research and development. The 6- FQs identified as potentially effective against M. tuberculosis were subjected to an additional SSER study for prediction of their toxicological profile. The assessment of structurally-driven adverse effects which might hamper the potential of new drug candidates is mandatory for an effective drug design. We applied publicly available knowledge-based (expert) systems and Quantitative Structure-Activity Relationship (QSAR) models in order to prepare a priority list of active compounds. A preferred order of drug candidates was obtained, so that the less harmful candidates were identified for further testing. TOXTREE expert system as well as some QSAR models developed in the framework of EC funded project CAESAR were used to assess toxicity. CAESAR models were developed according to the OECD

  10. 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