Search for sterile neutrinos with IceCube DeepCore

Energy Technology Data Exchange (ETDEWEB)

Terliuk, Andrii [DESY, Platanenallee 6, 15738 Zeuthen (Germany); Collaboration: IceCube-Collaboration

2016-07-01

The DeepCore detector is a sub-array of the IceCube Neutrino Observatory that lowers the energy threshold for neutrino detection down to approximately 10 GeV. DeepCore is used for a variety of studies including atmospheric neutrino oscillations. The standard three-neutrino oscillation paradigm is tested using the DeepCore detector by searching for an additional light, sterile neutrino with a mass on the order of 1 eV. Sterile neutrinos do not interact with the ordinary matter, however they can be mixed with the three active neutrino states. Such mixture changes the picture of standard neutrino oscillations for atmospheric neutrinos with energies below 100 GeV. The capabilities of DeepCore detector to measure such sterile neutrino mixing will be presented in this talk.

Studies of a full-scale mechanical prototype line for the ANTARES neutrino telescope and tests of a prototype instrument for deep-sea acoustic measurements

NARCIS (Netherlands)

Ageron, M.; Kooijman, P.

2007-01-01

A full-scale mechanical prototype line was deployed to a depth of 2500 m to test the leak tightness of the electronics containers and the pressure-resistant properties of an electromechanical cable under evaluation for use in the ANTARES deep-sea neutrino telescope. During a month-long immersion

Determination of strange sea distributions from {nu}N deep inelastic scattering

Energy Technology Data Exchange (ETDEWEB)

Alekhin, S. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)]|[Inst. for High Energy Physics, Protvino (Russian Federation); Kulagin, S. [Academy of Sciences of Russia, Moscow (Russian Federation). Inst. for Nuclear Research; Petti, R. [South Carolina Univ., Columbia, SC (United States). Dept. of Physics and Astronomy

2008-12-15

We present an analysis of the nucleon strange sea extracted from a global Parton Distribution Function fit including the neutrino and anti-neutrino dimuon data by the CCFR and NuTeV collaborations, the inclusive charged lepton-nucleon Deep Inelastic Scattering and Drell-Yan data. The (anti-)neutrino induced dimuon analysis is constrained by the semi-leptonic charmed-hadron branching ratio B{sub {mu}}=(8.8{+-}0.5)%, determined from the inclusive charmed hadron measurements performed by the FNAL-E531 and CHORUS neutrino emulsion experiments. Our analysis yields a strange sea suppression factor {kappa}(Q{sup 2}=20 GeV{sup 2})=0.62{+-}0.04, the most precise value available, an x-distribution of total strange sea that is slightly softer than the non-strange sea, and an asymmetry between strange and anti-strange quark distributions consistent with zero (integrated over x it is equal to 0.0013{+-}0.0009 at Q{sup 2}=20 GeV{sup 2}). (orig.)

Measurement of neutrino oscillations in atmospheric neutrinos with the IceCube DeepCore detector

Energy Technology Data Exchange (ETDEWEB)

Yanez Garza, Juan Pablo

2014-06-02

The study of neutrino oscillations is an active field of research. During the last couple of decades many experiments have measured the effects of oscillations, pushing the field from the discovery stage towards an era of precision and deeper understanding of the phenomenon. The IceCube Neutrino Observatory, with its low energy subarray, DeepCore, has the possibility of contributing to this field. IceCube is a 1 km{sup 3} ice Cherenkov neutrino telescope buried deep in the Antarctic glacier. DeepCore, a region of denser instrumentation in the lower center of IceCube, permits the detection of neutrinos with energies as low as 10 GeV. Every year, thousands of atmospheric neutrinos around these energies leave a strong signature in DeepCore. Due to their energy and the distance they travel before being detected, these neutrinos can be used to measure the phenomenon of oscillations. This work starts with a study of the potential of IceCube DeepCore to measure neutrino oscillations in different channels, from which the disappearance of ν{sub μ} is chosen to move forward. It continues by describing a novel method for identifying Cherenkov photons that traveled without being scattered until detected direct photons. These photons are used to reconstruct the incoming zenith angle of muon neutrinos. The total energy of the interacting neutrino is also estimated. In data taken in 343 days during 2011-2012, 1487 neutrino candidates with an energy between 7 GeV and 100 GeV are found inside the DeepCore volume. Compared to the expectation from the atmospheric neutrino flux without oscillations, this corresponds to a deficit of about 500 muon neutrino events. The oscillation parameters that describe the data best are sin{sup 2}(2θ{sub 23})=1(>0.94 at 68 % C.L.) and vertical stroke Δm{sup 2}{sub 32} vertical stroke =2.4{sub -0.4}{sup +0.6}.10{sup -3} eV{sup 2}, which are in agreement with the results reported by other experiments. The simulation follows the data closely

Signal classification for acoustic neutrino detection

International Nuclear Information System (INIS)

Neff, M.; Anton, G.; Enzenhöfer, A.; Graf, K.; Hößl, J.; Katz, U.; Lahmann, R.; Richardt, C.

2012-01-01

This article focuses on signal classification for deep-sea acoustic neutrino detection. In the deep sea, the background of transient signals is very diverse. Approaches like matched filtering are not sufficient to distinguish between neutrino-like signals and other transient signals with similar signature, which are forming the acoustic background for neutrino detection in the deep-sea environment. A classification system based on machine learning algorithms is analysed with the goal to find a robust and effective way to perform this task. For a well-trained model, a testing error on the level of 1% is achieved for strong classifiers like Random Forest and Boosting Trees using the extracted features of the signal as input and utilising dense clusters of sensors instead of single sensors.

The deep sea Acoustic Detection system AMADEUS

International Nuclear Information System (INIS)

Naumann, Christopher Lindsay

2008-01-01

As a part of the ANTARES neutrino telescope, the AMADEUS (ANTARES Modules for Acoustic Detection Under the Sea) system is an array of acoustical sensors designed to investigate the possibilities of acoustic detection of ultra-high energy neutrinos in the deep sea. The complete system will comprise a total of 36 acoustic sensors in six clusters on two of the ANTARES detector lines. With an inter-sensor spacing of about one metre inside the clusters and between 15 and 340 metres between the different clusters, it will cover a wide range of distances as will as provide a considerable lever arm for point source triangulation. Three of these clusters have already been deployed in 2007 and have been in operation since, currently yielding around 2GB of acoustic data per day. The remaining three clusters are scheduled to be deployed in May 2008 together with the final ANTARES detector line. Apart from proving the feasibility of operating an acoustic detection system in the deep sea, the main aim of this project is an in-depth survey of both the acoustic properties of the sea water and the acoustic background present at the detector site. It will also serve as a platform for the development and refinement of triggering, filtering and reconstruction algorithms for acoustic particle detection. In this presentation, a description of the acoustic sensor and read-out system is given, together with examples for the reconstruction and evaluation of the acoustic data.

Water transparency measurements in the deep Ionian Sea

CERN Document Server

Anassontzis, E G; Belias, A; Fotiou, A; Grammatikakis, G; Kontogiannis, H; Koske, P; Koutsoukos, S; Lykoussis, V; Markopoulos, E; Psallidas, A; Resvanis, L K; Siotis, I; Stavrakakis, S; Stavropoulos, G; Zhukov, V A

2010-01-01

A long optical base line spectrophotometer designed to measure light transmission in deep sea waters is described. The variable optical path length allows measurements without the need for absolute or external calibration. The spectrophotometer uses eight groups of uncollimated light sources emitting in the range 370–530 nm and was deployed at various depths at two locations in the Ionian Sea that are candidate sites for a future underwater neutrino telescope. Light transmission spectra at the two locations are presented and compared.

A mechanical design for a detection unit for a deep-sea neutrino telescope

NARCIS (Netherlands)

Berbee, E.M.; Boer Rookhuizen, H.; Heine, E.; de Wolf, E.

2013-01-01

The future KM3NeT neutrino telescope will be built on the seabed of the Mediterranean Sea at a depth between three and five kilometers. The high ambient pressure, but also the fact that the detector is hardly accessible, put severe constraints on the mechanical design of the detection units of the

Studies of a full-scale mechanical prototype line for the ANTARES neutrino telescope and tests of a prototype instrument for deep-sea acoustic measurements

Energy Technology Data Exchange (ETDEWEB)

Ageron, M. [CPPM-Centre de Physique des Particules de Marseille, CNRS/IN2P3 et Universite de la Mediterranee, 163 Avenue de Luminy, Case 902, 13288 Marseille Cedex 9 (France); Aguilar, J.A. [IFIC-Instituto de Fisica Corpuscular, Edificios Investigacion de Paterna, CSIC-Universitat de Valencia, Apdo. de Correos 22085, 46071 Valencia (Spain); Albert, A. [GRPHE-Groupe de Recherche en Physique des Hautes Energies, Universite de Haute Alsace, 61 Rue Albert Camus, 68093 Mulhouse Cedex (France); Ameli, F. [Dipartimento di Fisica dell' Universita ' La Sapienza' e Sezione INFN, P.le Aldo Moro 2, 00185 Roma (Italy); Anghinolfi, M. [Dipartimento di Fisica dell' Universita e Sezione INFN, Via Dodecaneso 33, 16146 Genova (Italy); Anton, G. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erwin-Rommel-Str. 1, D-91058 Erlangen (Germany); Anvar, S.; Ardellier-Desages, F. [DSM/DAPNIA-Direction des Sciences de la Matiere, Laboratoire de Recherche sur les lois Fondamentales de l' Univers, CEA Saclay, 91191 Gif-sur-Yvette Cedex (France); Aslanides, E.; Aubert, J.-J. [CPPM-Centre de Physique des Particules de Marseille, CNRS/IN2P3 et Universite de la Mediterranee, 163 Avenue de Luminy, Case 902, 13288 Marseille Cedex 9 (France); Auer, R. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erwin-Rommel-Str. 1, D-91058 Erlangen (Germany); Barbarito, E. [Dipartimento Interateneo di Fisica e Sezione INFN, Via E. Orabona 4, 70126 Bari (Italy); Basa, S. [LAM-Laboratoire d' Astrophysique de Marseille, CNRS/INSU et Universite de Provence, Traverse du Siphon-Les Trois Lucs, BP 8, 13012 Marseille Cedex 12 (France); Battaglieri, M. [Dipartimento di Fisica dell' Universita e Sezione INFN, Via Dodecaneso 33, 16146 Genova (Italy); Bazzotti, M.; Becherini, Y. [Dipartimento di Fisica dell' Universita e Sezione INFN, Viale Berti Pichat 6/2, 40127 Bologna (Italy)] (and others)

2007-11-01

A full-scale mechanical prototype line was deployed to a depth of 2500 m to test the leak tightness of the electronics containers and the pressure-resistant properties of an electromechanical cable under evaluation for use in the ANTARES deep-sea neutrino telescope. During a month-long immersion study, line parameter data were taken using miniature autonomous data loggers and shore-based optical time domain reflectometry. Details of the mechanical prototype line, the electromechanical cable and data acquisition are presented. Data taken during the immersion study revealed deficiencies in the pressure resistance of the electromechanical cable terminations at the entry points to the electronics containers. The improvements to the termination, which have been integrated into subsequent detection lines, are discussed. The line also allowed deep-sea acoustic measurements with a prototype hydrophone system. The technical setup of this system is described, and the first results of the data analysis are presented.

Studies of a full-scale mechanical prototype line for the ANTARES neutrino telescope and tests of a prototype instrument for deep-sea acoustic measurements

International Nuclear Information System (INIS)

Ageron, M.; Aguilar, J.A.; Albert, A.; Ameli, F.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardellier-Desages, F.; Aslanides, E.; Aubert, J.-J.; Auer, R.; Barbarito, E.; Basa, S.; Battaglieri, M.; Bazzotti, M.; Becherini, Y.

2007-01-01

A full-scale mechanical prototype line was deployed to a depth of 2500 m to test the leak tightness of the electronics containers and the pressure-resistant properties of an electromechanical cable under evaluation for use in the ANTARES deep-sea neutrino telescope. During a month-long immersion study, line parameter data were taken using miniature autonomous data loggers and shore-based optical time domain reflectometry. Details of the mechanical prototype line, the electromechanical cable and data acquisition are presented. Data taken during the immersion study revealed deficiencies in the pressure resistance of the electromechanical cable terminations at the entry points to the electronics containers. The improvements to the termination, which have been integrated into subsequent detection lines, are discussed. The line also allowed deep-sea acoustic measurements with a prototype hydrophone system. The technical setup of this system is described, and the first results of the data analysis are presented

Search for neutrino point sources with an all-sky autocorrelation analysis in IceCube

Energy Technology Data Exchange (ETDEWEB)

Turcati, Andrea; Bernhard, Anna; Coenders, Stefan [TU, Munich (Germany); Collaboration: IceCube-Collaboration

2016-07-01

The IceCube Neutrino Observatory is a cubic kilometre scale neutrino telescope located in the Antarctic ice. Its full-sky field of view gives unique opportunities to study the neutrino emission from the Galactic and extragalactic sky. Recently, IceCube found the first signal of astrophysical neutrinos with energies up to the PeV scale, but the origin of these particles still remains unresolved. Given the observed flux, the absence of observations of bright point-sources is explainable with the presence of numerous weak sources. This scenario can be tested using autocorrelation methods. We present here the sensitivities and discovery potentials of a two-point angular correlation analysis performed on seven years of IceCube data, taken between 2008 and 2015. The test is applied on the northern and southern skies separately, using the neutrino energy information to improve the effectiveness of the method.

ANTARES: The first undersea neutrino telescope

Science.gov (United States)

Ageron, M.; Aguilar, J. A.; Al Samarai, I.; Albert, A.; Ameli, F.; André, M.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Arnaud, K.; Aslanides, E.; Assis Jesus, A. C.; Astraatmadja, T.; Aubert, J.-J.; Auer, R.; Barbarito, E.; Baret, B.; Basa, S.; Bazzotti, M.; Becherini, Y.; Beltramelli, J.; Bersani, A.; Bertin, V.; Beurthey, S.; Biagi, S.; Bigongiari, C.; Billault, M.; Blaes, R.; Bogazzi, C.; de Botton, N.; Bou-Cabo, M.; Boudahef, B.; Bouwhuis, M. C.; Brown, A. M.; Brunner, J.; Busto, J.; Caillat, L.; Calzas, A.; Camarena, F.; Capone, A.; Caponetto, L.; Cârloganu, C.; Carminati, G.; Carmona, E.; Carr, J.; Carton, P. H.; Cassano, B.; Castorina, E.; Cecchini, S.; Ceres, A.; Chaleil, Th.; Charvis, Ph.; Chauchot, P.; Chiarusi, T.; Circella, M.; Compère, C.; Coniglione, R.; Coppolani, X.; Cosquer, A.; Costantini, H.; Cottini, N.; Coyle, P.; Cuneo, S.; Curtil, C.; D'Amato, C.; Damy, G.; van Dantzig, R.; de Bonis, G.; Decock, G.; Decowski, M. P.; Dekeyser, I.; Delagnes, E.; Desages-Ardellier, F.; Deschamps, A.; Destelle, J.-J.; di Maria, F.; Dinkespiler, B.; Distefano, C.; Dominique, J.-L.; Donzaud, C.; Dornic, D.; Dorosti, Q.; Drogou, J.-F.; Drouhin, D.; Druillole, F.; Durand, D.; Durand, R.; Eberl, T.; Emanuele, U.; Engelen, J. J.; Ernenwein, J.-P.; Escoffier, S.; Falchini, E.; Favard, S.; Fehr, F.; Feinstein, F.; Ferri, M.; Ferry, S.; Fiorello, C.; Flaminio, V.; Folger, F.; Fritsch, U.; Fuda, J.-L.; Galatá, S.; Galeotti, S.; Gay, P.; Gensolen, F.; Giacomelli, G.; Gojak, C.; Gómez-González, J. P.; Goret, Ph.; Graf, K.; Guillard, G.; Halladjian, G.; Hallewell, G.; van Haren, H.; Hartmann, B.; Heijboer, A. J.; Heine, E.; Hello, Y.; Henry, S.; Hernández-Rey, J. J.; Herold, B.; Hößl, J.; Hogenbirk, J.; Hsu, C. C.; Hubbard, J. R.; Jaquet, M.; Jaspers, M.; de Jong, M.; Jourde, D.; Kadler, M.; Kalantar-Nayestanaki, N.; Kalekin, O.; Kappes, A.; Karg, T.; Karkar, S.; Karolak, M.; Katz, U.; Keller, P.; Kestener, P.; Kok, E.; Kok, H.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kretschmer, W.; Kruijer, A.; Kuch, S.; Kulikovskiy, V.; Lachartre, D.; Lafoux, H.; Lagier, P.; Lahmann, R.; Lahonde-Hamdoun, C.; Lamare, P.; Lambard, G.; Languillat, J.-C.; Larosa, G.; Lavalle, J.; Le Guen, Y.; Le Provost, H.; Levansuu, A.; Lefèvre, D.; Legou, T.; Lelaizant, G.; Lévéque, C.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Louis, F.; Lucarelli, F.; Lyashuk, V.; Magnier, P.; Mangano, S.; Marcel, A.; Marcelin, M.; Margiotta, A.; Martinez-Mora, J. A.; Masullo, R.; Mazéas, F.; Mazure, A.; Meli, A.; Melissas, M.; Migneco, E.; Mongelli, M.; Montaruli, T.; Morganti, M.; Moscoso, L.; Motz, H.; Musumeci, M.; Naumann, C.; Naumann-Godo, M.; Neff, M.; Niess, V.; Nooren, G. J. L.; Oberski, J. E. J.; Olivetto, C.; Palanque-Delabrouille, N.; Palioselitis, D.; Papaleo, R.; Păvălaş, G. E.; Payet, K.; Payre, P.; Peek, H.; Petrovic, J.; Piattelli, P.; Picot-Clemente, N.; Picq, C.; Piret, Y.; Poinsignon, J.; Popa, V.; Pradier, T.; Presani, E.; Prono, G.; Racca, C.; Raia, G.; van Randwijk, J.; Real, D.; Reed, C.; Réthoré, F.; Rewiersma, P.; Riccobene, G.; Richardt, C.; Richter, R.; Ricol, J. S.; Rigaud, V.; Roca, V.; Roensch, K.; Rolin, J.-F.; Rostovtsev, A.; Rottura, A.; Roux, J.; Rujoiu, M.; Ruppi, M.; Russo, G. V.; Salesa, F.; Salomon, K.; Sapienza, P.; Schmitt, F.; Schöck, F.; Schuller, J.-P.; Schüssler, F.; Sciliberto, D.; Shanidze, R.; Shirokov, E.; Simeone, F.; Sottoriva, A.; Spies, A.; Spona, T.; Spurio, M.; Steijger, J. J. M.; Stolarczyk, Th.; Streeb, K.; Sulak, L.; Taiuti, M.; Tamburini, C.; Tao, C.; Tasca, L.; Terreni, G.; Tezier, D.; Toscano, S.; Urbano, F.; Valdy, P.; Vallage, B.; van Elewyck, V.; Vannoni, G.; Vecchi, M.; Venekamp, G.; Verlaat, B.; Vernin, P.; Virique, E.; de Vries, G.; van Wijk, R.; Wijnker, G.; Wobbe, G.; de Wolf, E.; Yakovenko, Y.; Yepes, H.; Zaborov, D.; Zaccone, H.; Zornoza, J. D.; Zúñiga, J.

2011-11-01

The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given.

ANTARES: The first undersea neutrino telescope

International Nuclear Information System (INIS)

Ageron, M.; Aguilar, J.A.; Al Samarai, I.; Albert, A.; Ameli, F.; Andre, M.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Arnaud, K.; Aslanides, E.; Assis Jesus, A.C.; Astraatmadja, T.; Aubert, J.-J.; Auer, R.; Barbarito, E.; Baret, B.

2011-01-01

The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given.

Deep-sea bioluminescence blooms after dense water formation at the ocean surface.

Directory of Open Access Journals (Sweden)

Christian Tamburini

Full Text Available The deep ocean is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June 2010 at the ANTARES underwater neutrino telescope in the deep NW Mediterranean Sea, jointly with synchronous hydrological records. This is the longest continuous time-series of deep-sea bioluminescence ever recorded. Our record reveals several weeks long, seasonal bioluminescence blooms with light intensity up to two orders of magnitude higher than background values, which correlate to changes in the properties of deep waters. Such changes are triggered by the winter cooling and evaporation experienced by the upper ocean layer in the Gulf of Lion that leads to the formation and subsequent sinking of dense water through a process known as "open-sea convection". It episodically renews the deep water of the study area and conveys fresh organic matter that fuels the deep ecosystems. Luminous bacteria most likely are the main contributors to the observed deep-sea bioluminescence blooms. Our observations demonstrate a consistent and rapid connection between deep open-sea convection and bathypelagic biological activity, as expressed by bioluminescence. In a setting where dense water formation events are likely to decline under global warming scenarios enhancing ocean stratification, in situ observatories become essential as environmental sentinels for the monitoring and understanding of deep-sea ecosystem shifts.

Deep-sea bioluminescence blooms after dense water formation at the ocean surface.

Science.gov (United States)

Tamburini, Christian; Canals, Miquel; Durrieu de Madron, Xavier; Houpert, Loïc; Lefèvre, Dominique; Martini, Séverine; D'Ortenzio, Fabrizio; Robert, Anne; Testor, Pierre; Aguilar, Juan Antonio; Samarai, Imen Al; Albert, Arnaud; André, Michel; Anghinolfi, Marco; Anton, Gisela; Anvar, Shebli; Ardid, Miguel; Jesus, Ana Carolina Assis; Astraatmadja, Tri L; Aubert, Jean-Jacques; Baret, Bruny; Basa, Stéphane; Bertin, Vincent; Biagi, Simone; Bigi, Armando; Bigongiari, Ciro; Bogazzi, Claudio; Bou-Cabo, Manuel; Bouhou, Boutayeb; Bouwhuis, Mieke C; Brunner, Jurgen; Busto, José; Camarena, Francisco; Capone, Antonio; Cârloganu, Christina; Carminati, Giada; Carr, John; Cecchini, Stefano; Charif, Ziad; Charvis, Philippe; Chiarusi, Tommaso; Circella, Marco; Coniglione, Rosa; Costantini, Heide; Coyle, Paschal; Curtil, Christian; Decowski, Patrick; Dekeyser, Ivan; Deschamps, Anne; Donzaud, Corinne; Dornic, Damien; Dorosti, Hasankiadeh Q; Drouhin, Doriane; Eberl, Thomas; Emanuele, Umberto; Ernenwein, Jean-Pierre; Escoffier, Stéphanie; Fermani, Paolo; Ferri, Marcelino; Flaminio, Vincenzo; Folger, Florian; Fritsch, Ulf; Fuda, Jean-Luc; Galatà, Salvatore; Gay, Pascal; Giacomelli, Giorgio; Giordano, Valentina; Gómez-González, Juan-Pablo; Graf, Kay; Guillard, Goulven; Halladjian, Garadeb; Hallewell, Gregory; van Haren, Hans; Hartman, Joris; Heijboer, Aart J; Hello, Yann; Hernández-Rey, Juan Jose; Herold, Bjoern; Hößl, Jurgen; Hsu, Ching-Cheng; de Jong, Marteen; Kadler, Matthias; Kalekin, Oleg; Kappes, Alexander; Katz, Uli; Kavatsyuk, Oksana; Kooijman, Paul; Kopper, Claudio; Kouchner, Antoine; Kreykenbohm, Ingo; Kulikovskiy, Vladimir; Lahmann, Robert; Lamare, Patrick; Larosa, Giuseppina; Lattuada, Dario; Lim, Gordon; Presti, Domenico Lo; Loehner, Herbert; Loucatos, Sotiris; Mangano, Salvatore; Marcelin, Michel; Margiotta, Annarita; Martinez-Mora, Juan Antonio; Meli, Athina; Montaruli, Teresa; Moscoso, Luciano; Motz, Holger; Neff, Max; Nezri, Emma Nuel; Palioselitis, Dimitris; Păvălaş, Gabriela E; Payet, Kevin; Payre, Patrice; Petrovic, Jelena; Piattelli, Paolo; Picot-Clemente, Nicolas; Popa, Vlad; Pradier, Thierry; Presani, Eleonora; Racca, Chantal; Reed, Corey; Riccobene, Giorgio; Richardt, Carsten; Richter, Roland; Rivière, Colas; Roensch, Kathrin; Rostovtsev, Andrei; Ruiz-Rivas, Joaquin; Rujoiu, Marius; Russo, Valerio G; Salesa, Francisco; Sánchez-Losa, Augustin; Sapienza, Piera; Schöck, Friederike; Schuller, Jean-Pierre; Schussler, Fabian; Shanidze, Rezo; Simeone, Francesco; Spies, Andreas; Spurio, Maurizio; Steijger, Jos J M; Stolarczyk, Thierry; Taiuti, Mauro G F; Toscano, Simona; Vallage, Bertrand; Van Elewyck, Véronique; Vannoni, Giulia; Vecchi, Manuela; Vernin, Pascal; Wijnker, Guus; Wilms, Jorn; de Wolf, Els; Yepes, Harold; Zaborov, Dmitry; De Dios Zornoza, Juan; Zúñiga, Juan

2013-01-01

The deep ocean is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June 2010 at the ANTARES underwater neutrino telescope in the deep NW Mediterranean Sea, jointly with synchronous hydrological records. This is the longest continuous time-series of deep-sea bioluminescence ever recorded. Our record reveals several weeks long, seasonal bioluminescence blooms with light intensity up to two orders of magnitude higher than background values, which correlate to changes in the properties of deep waters. Such changes are triggered by the winter cooling and evaporation experienced by the upper ocean layer in the Gulf of Lion that leads to the formation and subsequent sinking of dense water through a process known as "open-sea convection". It episodically renews the deep water of the study area and conveys fresh organic matter that fuels the deep ecosystems. Luminous bacteria most likely are the main contributors to the observed deep-sea bioluminescence blooms. Our observations demonstrate a consistent and rapid connection between deep open-sea convection and bathypelagic biological activity, as expressed by bioluminescence. In a setting where dense water formation events are likely to decline under global warming scenarios enhancing ocean stratification, in situ observatories become essential as environmental sentinels for the monitoring and understanding of deep-sea ecosystem shifts.

ANTARES: An underwater neutrino observatory for the exploration of both the deep Ocean and the deep Universe

International Nuclear Information System (INIS)

Escoffier, Stephanie

2012-01-01

Neutrino astronomy is a new and unique method to explore the Universe. It is full of promises, such as improving our knowledge on cosmic accelerators or distinguishing unambiguously between hadronic and electronic acceleration mechanisms of very high energy cosmic rays. In this document the issues of neutrino astronomy are introduced and an overview of current and former neutrino telescopes is given, with a description of the performance results expected from the ANTARES underwater detector. My research path is marked by contributions to the detector calibration and by studies of the trigger system with the development of a new data selection algorithm. The potential for discovery of the ANTARES telescope is then illustrated with two analyses, one dedicated to the research of high-energy neutrinos from gamma ray bursters and the other dedicated to the search for magnetic monopoles. Within this dissertation, I also discuss the opportunity offered by a submarine detector to understand the deep-sea environment. Indeed, ANTARES is a multidisciplinary, permanent marine observatory bringing its brick to the edifice of the global understanding of physical phenomena and biological oceanography in the context of global changes. I illustrate these remarks with studies on marine bioluminescence observed by ANTARES and its connection to the dense water formation originating from the Gulf of Lion. (author)

Long-term measurements of acoustic background noise in very deep sea

International Nuclear Information System (INIS)

Riccobene, G.

2009-01-01

The NEMO (NEutrino Mediterranean Observatory) Collaboration installed, 25 km E offshore the port of Catania (Sicily) at 2000 m depth, an underwater laboratory to perform long-term tests of prototypes and new technologies for an underwater high energy neutrino km 3 -scale detector in the Mediterranean Sea. In this framework the Collaboration deployed and successfully operated for about two years, starting from January 2005, an experimental apparatus for on-line monitoring of deep-sea noise. The station was equipped with four hydrophones and it is operational in the range 30 Hz-43 kHz. This interval of frequencies matches the range suitable for the proposed acoustic detection technique of high energy neutrinos. Hydrophone signals were digitized underwater at 96 kHz sampling frequency and 24 bits resolution. The stored data library, consisting of more than 2000 h of recordings, is a unique tool to model underwater acoustic noise at large depth, to characterize its variations as a function of environmental parameters, biological sources and human activities (ship traffic, etc.), and to determine the presence of cetaceans in the area.

Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE): Conceptual Design Report. Volume 1: The LBNF and DUNE Projects

Energy Technology Data Exchange (ETDEWEB)

Acciarri, R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); et al.

2016-01-22

This document presents the Conceptual Design Report (CDR) put forward by an international neutrino community to pursue the Deep Underground Neutrino Experiment at the Long-Baseline Neutrino Facility (LBNF/DUNE), a groundbreaking science experiment for long-baseline neutrino oscillation studies and for neutrino astrophysics and nucleon decay searches. The DUNE far detector will be a very large modular liquid argon time-projection chamber (LArTPC) located deep underground, coupled to the LBNF multi-megawatt wide-band neutrino beam. DUNE will also have a high-resolution and high-precision near detector.

Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) Conceptual Design Report Volume 1: The LBNF and DUNE Projects

CERN Document Server

Acciarri, R.; Adamowski, M.; Adams, C.; Adamson, P.; Adhikari, S.; Ahmad, Z.; Albright, C.H.; Alion, T.; Amador, E.; Anderson, J.; Anderson, K.; Andreopoulos, C.; Andrews, M.; Andrews, R.; Anghel, I.; Anjos, J. d.; Ankowski, A.; Antonello, M.; Aranda Fernandez, A.; Ariga, A.; Ariga, T.; Aristizabal, D.; Arrieta-Diaz, E.; Aryal, K.; Asaadi, J.; Asner, D.; Athar, M.S.; Auger, M.; Aurisano, A.; Aushev, V.; Autiero, D.; Avila, M.; Back, J.J.; Bai, X.; Baibussinov, B.; Baird, M.; Balantekin, B.; Baller, B.; Ballett, P.; Bambah, B.; Bansal, M.; Bansal, S.; Barker, G.J.; Barletta, W.A.; Barr, G.; Barros, N.; Bartosz, B.; Bartoszek, L.; Bashyal, A.; Bass, M.; Bay, F.; Beacom, J.; Behera, B.R.; Bellettini, G.; Bellini, V.; Beltramello, O.; Benekos, N.; Benetti, P.A.; Bercellie, A.; Bergevin, M.; Berman, E.; Berns, H.; Bernstein, R.; Bertolucci, S.; Bhandari, B.; Bhatnagar, V.; Bhuyan, B.; Bian, J.; Biery, K.; Bishai, M.; Blackburn, T.; Blake, A.; Blaszczyk, F. d. M.; Blaufuss, E.; Bleakley, B.; Blucher, E.; Bocean, V.; Boffelli, F.; Boissevain, J.; Bolognesi, S.; Bolton, T.; Bonesini, M.; Boone, T.; Booth, C.; Bordoni, S.; Borysova, M.; Bourguille, B.; Boyd, S.B.; Brailsford, D.; Brandt, A.; Bremer, J.; Brice, S.; Bromberg, C.; Brooijmans, G.; Brown, G.; Brown, R.; Brunetti, G.; Bu, X.; Buchanan, N.; Budd, H.; Bugg, B.; Calafiura, P.; Calligarich, E.; Calvo, E.; Camilleri, L.; Campanelli, M.; Cantini, C.; Carls, B.; Carr, R.; Cascella, M.; Castromonte, C.; Mur, E.Catano; Cavanna, F.; Centro, S.; Cervera Villanueva, A.; Chalifour, M.; Chandratre, V.B.; Chatterjee, A.; Chattopadhyay, S.; Chattopadhyay, S.; Chaussard, L.; Chembra, S.; Chen, H.; Chen, K.; Chen, M.; Cherdack, D.; Chi, C.; Childress, S.; Choubey, S.; Choudhary, B.C.; Christodoulou, G.; Christofferson, C.; Church, E.; Cianci, D.; Cline, D.; Coan, T.; Cocco, A.; Coelho, J.; Cole, P.; Collin, G.; Conrad, J.M.; Convery, M.; Corey, R.; Corwin, L.; Cranshaw, J.; Crivelli, P.; Cronin-Hennessy, D.; Curioni, A.; Cushing, J.; Adams, D.L.; Dale, D.; Das, S.R.; Davenne, T.; Davies, G.S.; Davies, J.; Dawson, J.; De, K.; de Gouvea, A.; de Jong, J.K.; de Jong, P.; De Lurgio, P.; Decowski, M.; Delbart, A.; Densham, C.; Dharmapalan, R.; Dhingra, N.; Di Luise, S.; Diamantopoulou, M.; Diaz, J.S.; Diaz Bautista, G.; Diwan, M.; Djurcic, Z.; Dolph, J.; Drake, G.; Duchesneau, D.; Duvernois, M.; Duyang, H.; Dwyer, D.A.; Dye, S.; Dytman, S.; Eberly, B.; Edgecock, R.; Edmunds, D.; Elliott, S.; Elnimr, M.; Emery, S.; Endress, E.; Eno, S.; Ereditato, A.; Escobar, C.O.; Evans, J.; Falcone, A.; Falk, L.; Farbin, A.; Farnese, C.; Farzan, Y.; Fava, A.; Favilli, L.; Felde, J.; Felix, J.; Fernandes, S.; Fields, L.; Finch, A.; Fitton, M.; Fleming, B.; Forest, T.; Fowler, J.; Fox, W.; Fried, J.; Friedland, A.; Fuess, S.; Fujikawa, B.; Gago, A.; Gallagher, H.; Galymov, S.; Gamble, T.; Gandhi, R.; Garcia-Gamez, D.; Gardiner, S.; Garvey, G.; Gehman, V.M.; Gendotti, A.; Geronimo, G. d.; Ghag, C.; Ghoshal, P.; Gibin, D.; Gil-Botella, I.; Gill, R.; Girardelli, D.; Giri, A.; Glavin, S.; Goeldi, D.; Golapinni, S.; Gold, M.; Gomes, R.A.; Gomez Cadenas, J.J.; Goodman, M.C.; Gorbunov, D.; Goswami, S.; Graf, N.; Graf, N.; Graham, M.; Gramelini, E.; Gran, R.; Grant, C.; Grant, N.; Greco, V.; Greenlee, H.; Greenler, L.; Greenley, C.; Groh, M.; Grullon, S.; Grundy, T.; Grzelak, K.; Guardincerri, E.; Guarino, V.; Guarnaccia, E.; Guedes, G.P.; Guenette, R.; Guglielmi, A.; Habig, A.T.; Hackenburg, R.W.; Hackenburg, A.; Hadavand, H.; Haenni, R.; Hahn, A.; Haigh, M.D.; Haines, T.; Hamernik, T.; Handler, T.; Hans, S.; Harris, D.; Hartnell, J.; Hasegawa, T.; Hatcher, R.; Hatzikoutelis, A.; Hays, S.; Hazen, E.; Headley, M.; Heavey, A.; Heeger, K.; Heise, J.; Hennessy, K.; Hewes, J.; Higuera, A.; Hill, T.; Himmel, A.; Hogan, M.; Holanda, P.; Holin, A.; Honey, W.; Horikawa, S.; Horton-Smith, G.; Howard, B.; Howell, J.; Hurh, P.; Huston, J.; Hylen, J.; Imlay, R.; Insler, J.; Introzzi, G.; Ioanisyan, D.; Ioannisian, A.; Iwamoto, K.; Izmaylov, A.; Jackson, C.; Jaffe, D.E.; James, C.; James, E.; Jediny, F.; Jen, C.; Jhingan, A.; Jimenez, S.; Jo, J.H.; Johnson, M.; Johnson, R.; Johnstone, J.; Jones, B.J.; Joshi, J.; Jostlein, H.; Jung, C.K.; Junk, T.; Kaboth, A.; Kadel, R.; Kafka, T.; Kalousis, L.; Kamyshkov, Y.; Karagiorgi, G.; Karasavvas, D.; Karyotakis, Y.; Kaur, A.; Kaur, P.; Kayser, B.; Kazaryan, N.; Kearns, E.; Keener, P.; Kemboi, S.; Kemp, E.; Kettell, S.H.; Khabibullin, M.; Khandaker, M.; Khotjantsev, A.; Kirby, B.; Kirby, M.; Klein, J.; Kobilarcik, T.; Kohn, S.; Koizumi, G.; Kopylov, A.; Kordosky, M.; Kormos, L.; Kose, U.; Kostelecky, A.; Kramer, M.; Kreslo, I.; Kriske, R.; Kropp, W.; Kudenko, Y.; Kudryavtsev, V.A.; Kulagin, S.; Kumar, A.; Kumar, G.; Kumar, J.; Kumar, L.; Kutter, T.; Laminack, A.; Lande, K.; Lane, C.; Lang, K.; Lanni, F.; Learned, J.; Lebrun, P.; Lee, D.; Lee, H.; Lee, K.; Lee, W.M.; Leigui de Oliveira, M.A.; Li, Q.; Li, S.; Li, S.; Li, X.; Li, Y.; Li, Z.; Libo, J.; Lin, C.S.; Lin, S.; Ling, J.; Link, J.; Liptak, Z.; Lissauer, D.; Littenberg, L.; Littlejohn, B.; Liu, Q.; Liu, T.; Lockwitz, S.; Lockyer, N.; Loew, T.; Lokajicek, M.; Long, K.; Lopes, M.D.L.; Lopez, J.P.; Losecco, J.; Louis, W.; Lowery, J.; Luethi, M.; Luk, K.; Lundberg, B.; Lundin, T.; Luo, X.; Lux, T.; Lykken, J.; Machado, A.A.; Macier, J.R.; Magill, S.; Mahler, G.; Mahn, K.; Malek, M.; Malhotra, S.; Malon, D.; Mammoliti, F.; Mancina, S.; Mandal, S.K.; Mandodi, S.; Manly, S.L.; Mann, A.; Marchionni, A.; Marciano, W.; Mariani, C.; Maricic, J.; Marino, A.; Marshak, M.; Marshall, C.; Marshall, J.; Marteau, J.; Martin-Albo, J.; Martinez, D.; Matsuno, S.; Matthews, J.; Mauger, C.; Mavrokoridis, K.; Mayilyan, D.; Mazzucato, E.; McCauley, N.; McCluskey, E.; McConkey, N.; McDonald, K.; McFarland, K.S.; McGowan, A.M.; McGrew, C.; McKeown, R.; McNulty, D.; McTaggart, R.; Mefodiev, A.; Mehrian, M.; Mehta, P.; Mei, D.; Mena, O.; Menary, S.; Mendez, H.; Menegolli, A.; Meng, G.; Meng, Y.; Mertins, D.; Merritt, H.; Messier, M.; Metcalf, W.; Mewes, M.; Meyer, H.; Miao, T.; Milincic, R.; Miller, W.; Mills, G.; Mineev, O.; Miranda, O.; Mishra, C.S.; Mishra, S.R.; Mitrica, B.; Mladenov, D.; Mocioiu, I.; Mohanta, R.; Mokhov, N.; Montanari, C.; Montanari, D.; Moon, J.; Mooney, M.; Moore, C.; Morfin, J.; Morgan, B.; Morris, C.; Morse, W.; Moss, Z.; Mossey, C.; Moura, C.A.; Mousseau, J.; Mualem, L.; Muether, M.; Mufson, S.; Murphy, S.; Musser, J.; Musser, R.; Nakajima, Y.; Naples, D.; Napolitano, J.; Navarro, J.; Navas, D.; Nelson, J.; Nessi, M.; Newcomer, M.; Ng, Y.; Nichol, R.; Nicholls, T.C.; Nikolics, K.; Niner, E.; Norris, B.; Noto, F.; Novakova, P.; Novella, P.; Nowak, J.; Nunes, M.S.; O'Keeffe, H.; Oldeman, R.; Oliveira, R.; Olson, T.; Onishchuk, Y.; Osta, J.; Ovsjannikova, T.; Page, B.; Pakvasa, S.; Pal, S.; Palamara, O.; Palazzo, A.; Paley, J.; Palomares, C.; Pantic, E.; Paolone, V.; Papadimitriou, V.; Park, J.; Parke, S.; Parsa, Z.; Pascoli, S.; Patterson, R.; Patton, S.; Patzak, T.; Paulos, B.; Paulucci, L.; Pavlovic, Z.; Pawloski, G.; Peeters, S.; Pennacchio, E.; Perch, A.; Perdue, G.N.; Periale, L.; Perkin, J.D.; Pessard, H.; Petrillo, G.; Petti, R.; Petukhov, A.; Pietropaolo, F.; Plunkett, R.; Pordes, S.; Potekhin, M.; Potenza, R.; Potukuchi, B.; Poudyal, N.; Prokofiev, O.; Pruthi, N.; Przewlocki, P.; Pushka, D.; Qian, X.; Raaf, J.L.; Raboanary, R.; Radeka, V.; Radovic, A.; Raffelt, G.; Rakhno, I.; Rakotondramanana, H.T.; Rakotondravohitra, L.; Ramachers, Y.A.; Rameika, R.; Ramsey, J.; Rappoldi, A.; Raselli, G.; Ratoff, P.; Rebel, B.; Regenfus, C.; Reichenbacher, J.; Reitzner, D.; Remoto, A.; Renshaw, A.; Rescia, S.; Richardson, M.; Rielage, K.; Riesselmann, K.; Robinson, M.; Rochester, L.; Rodrigues, O.B.; Rodrigues, P.; Roe, B.; Rosen, M.; Roser, R.M.; Ross-Lonergan, M.; Rossella, M.; Rubbia, A.; Rubbia, C.; Rucinski, R.; von Rohr, C.Rudolph; Russell, B.; Ruterbories, D.; Saakyan, R.; Sahu, N.; Sala, P.; Samios, N.; Sanchez, F.; Sanchez, M.; Sands, B.; Santana, S.; Santorelli, R.; Santucci, G.; Saoulidou, N.; Scaramelli, A.; Schellman, H.; Schlabach, P.; Schmitt, R.; Schmitz, D.; Schneps, J.; Scholberg, K.; Schukraft, A.; Schwehr, J.; Segreto, E.; Seibert, S.; Sepulveda-Quiroz, J.A.; Sergiampietri, F.; Sexton-Kennedy, L.; Sgalaberna, D.; Shaevitz, M.; Shahi, J.; Shahsavarani, S.; Shanahan, P.; Shankar, S.U.; Sharma, R.; Sharma, R.K.; Shaw, T.; Shrock, R.; Shyrma, I.; Simos, N.; Sinev, G.; Singh, I.; Singh, J.; Singh, J.; Singh, V.; Sinnis, G.; Sippach, W.; Smargianaki, D.; Smy, M.; Snider, E.; Snopok, P.; Sobczyk, J.; Sobel, H.; Soderberg, M.; Solomey, N.; Sondheim, W.; Sorel, M.; Sousa, A.; Soustruznik, K.; Spitz, J.; Spooner, N.J.; Stancari, M.; Stancu, I.; Stefan, D.; Steiner, H.M.; Stewart, J.; Stock, J.; Stoica, S.; Stone, J.; Strait, J.; Strait, M.; Strauss, T.; Striganov, S.; Sulej, R.; Sullivan, G.; Sun, Y.; Suter, L.; Sutera, C.M.; Svoboda, R.; Szczerbinska, B.; Szelc, A.; Soldner-Rembold, S.; Talaga, R.; Tamsett, M.; Tariq, S.; Tatar, E.; Tayloe, R.; Taylor, C.; Taylor, D.; Terao, K.; Thiesse, M.; Thomas, J.; Thompson, L.F.; Thomson, M.; Thorn, C.; Thorpe, M.; Tian, X.; Tiedt, D.; Timm, S.C.; Tonazzo, A.; Tope, T.; Topkar, A.; Torres, F.R.; Torti, M.; Tortola, M.; Tortorici, F.; Toups, M.; Touramanis, C.; Tripathi, M.; Tropin, I.; Tsai, Y.; Tsang, K.V.; Tsenov, R.; Tufanli, S.; Tull, C.; Turner, J.; Tzanov, M.; Tziaferi, E.; Uchida, Y.; Urheim, J.; Usher, T.; Vagins, M.; Vahle, P.; Valdiviesso, G.A.; Valerio, L.; Vallari, Z.; Valle, J.; Van Berg, R.; Van de Water, R.; Van Gemmeren, P.; Varanini, F.; Varner, G.; Vasseur, G.; Vaziri, K.; Velev, G.; Ventura, S.; Verdugo, A.; Viant, T.; Vieira, T.V.; Vignoli, C.; Vilela, C.; Viren, B.; Vrba, T.; Wachala, T.; Wahl, D.; Wallbank, M.; Walsh, N.; Wang, B.; Wang, H.; Wang, L.; Wang, T.; Warburton, T.K.; Warner, D.; Wascko, M.; Waters, D.; Watson, T.B.; Weber, A.; Weber, M.; Wei, W.; Weinstein, A.; Wells, D.; Wenman, D.; Wetstein, M.; White, A.; Whitehead, L.; Whittington, D.; Wilking, M.; Willhite, J.; Wilson, P.; Wilson, R.J.; Winslow, L.; Wittich, P.; Wojcicki, S.; Wong, H.H.; Wood, K.; Worcester, E.; Worcester, M.; Wu, S.; Xin, T.; Yanagisawa, C.; Yang, S.; Yang, T.; Yarritu, K.; Ye, J.; Yeh, M.; Yershov, N.; Yonehara, K.; Yu, B.; Yu, J.; Zalesak, J.; Zalewska, A.; Zamorano, B.; Zang, L.; Zani, A.; Zani, A.; Zavala, G.; Zeller, G.; Zhang, C.; Zhang, C.; Zimmerman, E.D.; Zito, M.; Zwaska, R.

2016-01-01

This document presents the Conceptual Design Report (CDR) put forward by an international neutrino community to pursue the Deep Underground Neutrino Experiment at the Long-Baseline Neutrino Facility (LBNF/DUNE), a groundbreaking science experiment for long-baseline neutrino oscillation studies and for neutrino astrophysics and nucleon decay searches. The DUNE far detector will be a very large modular liquid argon time-projection chamber (LArTPC) located deep underground, coupled to the LBNF multi-megawatt wide-band neutrino beam. DUNE will also have a high-resolution and high-precision near detector.

A large fiber sensor network for an acoustic neutrino telescope

Directory of Open Access Journals (Sweden)

Buis Ernst-Jan

2017-01-01

Full Text Available The scientific prospects of detecting neutrinos with an energy close or even higher than the GKZ cut-off energy has been discussed extensively in literature. It is clear that due to their expected low flux, the detection of these ultra-high energy neutrinos (Ev > 1018 eV requires a telescope larger than 100 km3. Acoustic detection may provide a way to observe these ultra-high energy cosmic neutrinos, as sound that they induce in the deep sea when neutrinos lose their energy travels undisturbed for many kilometers. To realize a large scale acoustic neutrino telescope, dedicated technology must be developed that allows for a deep sea sensor network. Fiber optic hydrophone technology provides a promising means to establish a large scale sensor network [1] with the proper sensitivity to detect the small signals from the neutrino interactions.

The Deep Underground Neutrino Experiment: The precision era of neutrino physics

Energy Technology Data Exchange (ETDEWEB)

Kemp, E. [Gleb Wataghin Institute of Physics, Universidade de Campinas - UNICAMP, Campinas Brazil

2017-12-01

The last decade was remarkable for neutrino physics. In particular, the phenomenon of neutrino flavor oscillations has been firmly established by a series of independent measurements. All parameters of the neutrino mixing are now known, and we have the elements to plan a judicious exploration of new scenarios that are opened by these recent advances. With precise measurements, we can test the three-neutrino paradigm, neutrino mass hierarchy, and charge conjugation parity (CP) asymmetry in the lepton sector. The future long-baseline experiments are considered to be a fundamental tool to deepen our knowledge of electroweak interactions. The Deep Underground Neutrino Experiment (DUNE) will detect a broadband neutrino beam from Fermilab in an underground massive liquid argon time-projection chamber at an L/E of about 103 km GeV-1 to reach good sensitivity for CP-phase measurements and the determination of the mass hierarchy. The dimensions and the depth of the far detector also create an excellent opportunity to look for rare signals like proton decay to study violation of the baryonic number, as well as supernova neutrino bursts, broadening the scope of the experiment to astrophysics and associated impacts in cosmology. In this paper, we discuss the physics motivations and the main experimental features of the DUNE project required to reach its scientific goals.

Neutrino telescopes in the World

International Nuclear Information System (INIS)

Ernenwein, J.-P.

2007-01-01

Neutrino astronomy has rapidly developed these last years, being the only way to get specific and reliable information about astrophysical objects still poorly understood.Currently two neutrino telescopes are operational in the World: BAIKAL, in the lake of the same name in Siberia, and AMANDA, in the ices of the South Pole. Two telescopes of the same type are under construction in the Mediterranean Sea: ANTARES and NESTOR. All these telescopes belong to a first generation, with an instrumented volume smaller or equal to 0.02 km3. Also in the Mediterranean Sea, the NEMO project is just in its starting phase, within the framework of a cubic kilometer size neutrino telescope study. Lastly, the ICECUBE detector, with a volume reaching about 1 km3, is under construction on the site of AMANDA experiment, while an extension of the BAIKAL detector toward km3 is under study. We will present here the characteristics of these experiments, as well as the results of their observations

Deep Secrets of the Neutrino: Physics Underground

Energy Technology Data Exchange (ETDEWEB)

Rowson, P.C.

2010-03-23

Among the many beautiful, unexpected and sometimes revolutionary discoveries to emerge from subatomic physics, probably none is more bizarre than an elementary particle known as the 'neutrino'. More than a trillion of these microscopic phantoms pass unnoticed through our bodies every second, and indeed, through the entire Earth - but their properties remain poorly understood. In recent years, exquisitely sensitive experiments, often conducted deep below ground, have brought neutrino physics to the forefront. In this talk, we will explore the neutrino - what we know, what we want to know, and how one experiment in a New Mexico mine is trying to get there.

Towards a large scale high energy cosmic neutrino undersea detector

Energy Technology Data Exchange (ETDEWEB)

Azoulay, R.; Berthier, R. [CEA Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Direction des Sciences de la Matiere; Arpesella, C. [Centre National de la Recherche Scientifique (CNRS), 13 - Marseille (France). Centre de Physique Theorique] [and others

1997-06-01

ANTARES collaboration proposes to study high energy cosmic neutrinos by using a deep sea Cherenkov detector. The potential interest of such a study for astrophysicists and particle physicists is developed. The different origins of cosmic neutrinos are reviewed. In order to observe with relevant statistic the flux of neutrinos from extra-galactic sources, a km-scale detector is necessary. The feasibility of such a detector is studied. A variety of technical problems have been solved. Some of them are standard for particle physicists: choice of photo-multipliers, monitoring, trigger, electronics, data acquisition, detector optimization. Others are more specific of sea science engineering particularly: detector deployment in deep sea, data transmission through optical cables, bio-fouling, effect of sea current. The solutions are presented and the sea engineering part involving detector installation will be tested near French coasts. It is scheduled to build a reduced-scale demonstrator within the next 2 years. (A.C.) 50 refs.

Towards a large scale high energy cosmic neutrino undersea detector

International Nuclear Information System (INIS)

Azoulay, R.; Berthier, R.; Arpesella, C.

1997-06-01

ANTARES collaboration proposes to study high energy cosmic neutrinos by using a deep sea Cherenkov detector. The potential interest of such a study for astrophysicists and particle physicists is developed. The different origins of cosmic neutrinos are reviewed. In order to observe with relevant statistic the flux of neutrinos from extra-galactic sources, a km-scale detector is necessary. The feasibility of such a detector is studied. A variety of technical problems have been solved. Some of them are standard for particle physicists: choice of photo-multipliers, monitoring, trigger, electronics, data acquisition, detector optimization. Others are more specific of sea science engineering particularly: detector deployment in deep sea, data transmission through optical cables, bio-fouling, effect of sea current. The solutions are presented and the sea engineering part involving detector installation will be tested near French coasts. It is scheduled to build a reduced-scale demonstrator within the next 2 years. (A.C.)

ANTARES: An Undersea Neutrino telescope

CERN Multimedia

2002-01-01

The ANTARES (Astronomy with a Neutrino Telescope and ${Abyss}$ environmental RESearch) deep-sea neutrino telescope is designed to search for neutrinos of astrophysical origin. Neutrinos are unique probes of the high energy universe; being neutral they are not deflected by magnetic fields and interacting weakly they can readily escape from the densest regions of the universe. Potential sources of neutrino are galactic (e.g supernova remnants, micro-quasars) and extra-galactic (e.g active galactic nuclei, gamma-ray bursters). Annihilation of dark matter particles in the Sun or Galactic Centre is another well motivated potential source of extra terrestrial neutrinos. The ANTARES detector is located 40 km off the coast of Toulon (France) at a depth of 2475m in the Mediterranean Sea. Being located in the Northern hemisphere it studies the Southern sky and in particular has the Galactic Centre in its field of view. Since 2006, the detector has operated continuously in a partial configuration. The detector was compl...

Larval transport modeling of deep-sea invertebrates can aid the search for undiscovered populations.

Directory of Open Access Journals (Sweden)

Jon M Yearsley

Full Text Available BACKGROUND: Many deep-sea benthic animals occur in patchy distributions separated by thousands of kilometres, yet because deep-sea habitats are remote, little is known about their larval dispersal. Our novel method simulates dispersal by combining data from the Argo array of autonomous oceanographic probes, deep-sea ecological surveys, and comparative invertebrate physiology. The predicted particle tracks allow quantitative, testable predictions about the dispersal of benthic invertebrate larvae in the south-west Pacific. PRINCIPAL FINDINGS: In a test case presented here, using non-feeding, non-swimming (lecithotrophic trochophore larvae of polyplacophoran molluscs (chitons, we show that the likely dispersal pathways in a single generation are significantly shorter than the distances between the three known population centres in our study region. The large-scale density of chiton populations throughout our study region is potentially much greater than present survey data suggest, with intermediate 'stepping stone' populations yet to be discovered. CONCLUSIONS/SIGNIFICANCE: We present a new method that is broadly applicable to studies of the dispersal of deep-sea organisms. This test case demonstrates the power and potential applications of our new method, in generating quantitative, testable hypotheses at multiple levels to solve the mismatch between observed and expected distributions: probabilistic predictions of locations of intermediate populations, potential alternative dispersal mechanisms, and expected population genetic structure. The global Argo data have never previously been used to address benthic biology, and our method can be applied to any non-swimming larvae of the deep-sea, giving information upon dispersal corridors and population densities in habitats that remain intrinsically difficult to assess.

Transmission of light in deep sea water at the site of the ANTARES neutrino telescope

Science.gov (United States)

ANTARES Collaboration; Aguilar, J. A.; Albert, A.; Amram, P.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardellier-Desages, F. E.; Aslanides, E.; Aubert, J.-J.; Azoulay, R.; Bailey, D.; Basa, S.; Battaglieri, M.; Becherini, Y.; Bellotti, R.; Beltramelli, J.; Bertin, V.; Billault, M.; Blaes, R.; Blanc, F.; Bland, R. W.; de Botton, N.; Boulesteix, J.; Bouwhuis, M. C.; Brooks, C. B.; Bradbury, S. M.; Bruijn, R.; Brunner, J.; Bugeon, F.; Burgio, G. F.; Cafagna, F.; Calzas, A.; Caponetto, L.; Carmona, E.; Carr, J.; Cartwright, S. L.; Cecchini, S.; Charvis, P.; Circella, M.; Colnard, C.; Compère, C.; Croquette, J.; Cooper, S.; Coyle, P.; Cuneo, S.; Damy, G.; van Dantzig, R.; Deschamps, A.; de Marzo, C.; Destelle, J.-J.; de Vita, R.; Dinkelspiler, B.; Dispau, G.; Drougou, J.-F.; Druillole, F.; Engelen, J.; Favard, S.; Feinstein, F.; Ferry, S.; Festy, D.; Fopma, J.; Fuda, J.-L.; Gallone, J.-M.; Giacomelli, G.; Girard, N.; Goret, P.; Gournay, J.-F.; Hallewell, G.; Hartmann, B.; Heijboer, A.; Hello, Y.; Hernández-Rey, J. J.; Herrouin, G.; Hößl, J.; Hoffmann, C.; Hubbard, J. R.; Jaquet, M.; de Jong, M.; Jouvenot, F.; Kappes, A.; Karg, T.; Karkar, S.; Karolak, M.; Katz, U.; Keller, P.; Kooijman, P.; Korolkova, E. V.; Kouchner, A.; Kretschmer, W.; Kudryavtsev, V. A.; Lafoux, H.; Lagier, P.; Lamare, P.; Languillat, J.-C.; Laubier, L.; Legou, T.; Le Guen, Y.; Le Provost, H.; Le van Suu, A.; Lo Nigro, L.; Lo Presti, D.; Loucatos, S.; Louis, F.; Lyashuk, V.; Magnier, P.; Marcelin, M.; Margiotta, A.; Maron, C.; Massol, A.; Mazéas, F.; Mazeau, B.; Mazure, A.; McMillan, J. E.; Michel, J.-L.; Millot, C.; Milovanovic, A.; Montanet, F.; Montaruli, T.; Morel, J.-P.; Moscoso, L.; Nezri, E.; Niess, V.; Nooren, G. J.; Ogden, P.; Olivetto, C.; Palanque-Delabrouille, N.; Payre, P.; Petta, C.; Pineau, J.-P.; Poinsignon, J.; Popa, V.; Potheau, R.; Pradier, T.; Racca, C.; Randazzo, N.; Real, D.; van Rens, B. A. P.; Réthoré, F.; Ripani, M.; Roca-Blay, V.; Romeyer, A.; Rollin, J.-F.; Romita, M.; Rose, H. J.; Rostovtsev, A.; Ruppi, M.; Russo, G. V.; Sacquin, Y.; Saouter, S.; Schuller, J.-P.; Schuster, W.; Sokalski, I.; Suvorova, O.; Spooner, N. J. C.; Spurio, M.; Stolarczyk, T.; Stubert, D.; Taiuti, M.; Thompson, L. F.; Tilav, S.; Usik, A.; Valdy, P.; Vallage, B.; Vaudaine, G.; Vernin, P.; Virieux, J.; Vladimirsky, E.; de Vries, G.; de Witt Huberts, P.; de Wolf, E.; Zaborov, D.; Zaccone, H.; Zakharov, V.; Zavatarelli, S.; de Zornoza, J. D.; Zúñiga, J.

2005-02-01

The ANTARES neutrino telescope is a large photomultiplier array designed to detect neutrino-induced upward-going muons by their Cherenkov radiation. Understanding the absorption and scattering of light in the deep Mediterranean is fundamental to optimising the design and performance of the detector. This paper presents measurements of blue and UV light transmission at the ANTARES site taken between 1997 and 2000. The derived values for the scattering length and the angular distribution of particulate scattering were found to be highly correlated, and results are therefore presented in terms of an absorption length λabs and an effective scattering length λscteff. The values for blue (UV) light are found to be λabs ≃ 60(26) m, λscteff≃265(122)m, with significant (˜15%) time variability. Finally, the results of ANTARES simulations showing the effect of these water properties on the anticipated performance of the detector are presented.

IceCube: Particle Astrophysics with High Energy Neutrinos

CERN Multimedia

Université de Genève

2012-01-01

GENEVA UNIVERSITY École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92 Monday 7 May 2012 17h. - Ecole de Physique, Auditoire Stueckelberg IceCube: Particle Astrophysics with High Energy Neutrinos Prof. Francis Halzen / University of Wisconsin, Madison Construction and commissioning of the cubic-kilometer IceCube neutrino detector and its low energy extension DeepCore have been completed. The instrument detects neutrinos over a wide energy range: from 10 GeV atmospheric neutrinos to 1010 GeV cosmogenic neutrinos. We will discuss initial results based on a subsample of the ~100,000 neutrino events recorded during construction. We will emphasize the first measurement of the high-energy atmospheric neutrino spectrum, the search for the still enigmatic sources of the Galactic and extragalactic cosmic rays and for the particle nature of dark matter. Une ve...

IceCube: An Instrument for Neutrino Astronomy

Energy Technology Data Exchange (ETDEWEB)

IceCube Collaboration; Halzen, F.; Klein, S.

2010-06-04

Neutrino astronomy beyond the Sun was first imagined in the late 1950s; by the 1970s, it was realized that kilometer-scale neutrino detectors were required. The first such instrument, IceCube, is near completion and taking data. The IceCube project transforms a cubic kilometer of deep and ultra-transparent Antarctic ice into a particle detector. A total of 5,160 optical sensors are embedded into a gigaton of Antarctic ice to detect the Cherenkov light emitted by secondary particles produced when neutrinos interact with nuclei in the ice. Each optical sensor is a complete data acquisition system, including a phototube, digitization electronics, control and trigger systems and LEDs for calibration. The light patterns reveal the type (flavor) of neutrino interaction and the energy and direction of the neutrino, making neutrino astronomy possible. The scientific missions of IceCube include such varied tasks as the search for sources of cosmic rays, the observation of Galactic supernova explosions, the search for dark matter, and the study of the neutrinos themselves. These reach energies well beyond those produced with accelerator beams.

Very low power, high voltage base for a Photo Multiplier Tube for the KM3NeT deep sea neutrino telescope

International Nuclear Information System (INIS)

Timmer, P; Heine, E; Peek, H

2010-01-01

The described system is developed in the framework of a deep-sea submerged Very Large Volume neutrino Telescope where photons are detected by a large number of Photo Multiplier Tubes. These PMTs are placed in optical modules (OM). A basic Cockcroft-Walton (CW) voltage multiplier circuit design is used to generate multiple voltages to drive the dynodes of the photomultiplier tube. To achieve a long lifetime and a high reliability the dissipation in the OM must be kept to the minimum. The design is also constrained by size restrictions, load current, voltage range, and the maximum allowable ripple in the output voltage. A surface mount PMT-base PCB prototype is designed and successfully tested. The system draws less than 1.5 mA of supply current at a voltage of 3.3 V with outputs up to -1400 Vdc cathode voltage, a factor 10 less than the commercially available state of the art.

Very low power, high voltage base for a Photo Multiplier Tube for the KM3NeT deep sea neutrino telescope

CERN Document Server

Timmer, P; Peek, H

2010-01-01

The described system is developed in the framework of a deep-sea submerged Very Large Volume neutrino Telescope where photons are detected by a large number of Photo Multiplier Tubes. These PMTs are placed in optical modules (OM). A basic Cockcroft-Walton (CW) voltage multiplier circuit design is used to generate multiple voltages to drive the dynodes of the photomultiplier tube. To achieve a long lifetime and a high reliability the dissipation in the OM must be kept to the minimum. The design is also constrained by size restrictions, load current, voltage range, and the maximum allowable ripple in the output voltage. A surface mount PMT-base PCB prototype is designed and successfully tested. The system draws less than 1.5 mA of supply current at a voltage of 3.3 V with outputs up to -1400 Vdc cathode voltage, a factor 10 less than the commercially available state of the art

A deep sea telescope for high energy neutrinos

Energy Technology Data Exchange (ETDEWEB)

Aslanides, E.; Aubert, J.J.; Basa, S. [and others

1999-05-01

This document presents the scientific motivation for building a high energy neutrino undersea detector, with an effective area of 0.1 km{sup 2}, along with a review of the technical issues involved in its design and construction. It contents: the scientific program, the detection principles, the research and development program, the detector design and performances and complementary technique. (A.L.B.)

A deep sea telescope for high energy neutrinos

International Nuclear Information System (INIS)

Aslanides, E.; Aubert, J.J.; Basa, S.

1999-05-01

This document presents the scientific motivation for building a high energy neutrino undersea detector, with an effective area of 0.1 km 2 , along with a review of the technical issues involved in its design and construction. It contents: the scientific program, the detection principles, the research and development program, the detector design and performances and complementary technique. (A.L.B.)

Measurement of Long Baseline Neutrino Oscillations and Improvements from Deep Learning

Energy Technology Data Exchange (ETDEWEB)

Psihas, Fernanda [Indiana U.

2018-01-01

NOvA is a long-baseline neutrino oscillation experiment which measures the oscillation of muon neutrinos from the NuMI beam at Fermilab after they travel through the Earth for 810 km. In this dissertation I describe the operations and monitoring of the detectors which make it possible to record over 98% of the delivered neutrino beam. I also present reconstruction and identification techniques using deep convolutional neural networks (CNNs), which are applicable to multiple analyses. Lastly, I detail the oscillation analyses in the $\

Study of multimuon-final states in deep inelastic neutrino scattering

International Nuclear Information System (INIS)

Renk, B.

1984-01-01

In this thesis the measurement of the momentum spectra, angular correlations, and transverse momentum distributions of the secondary muons produced in deep inelastic neutrino scattering at the CERN 300 GeV narrow band neutrino beam is described. From the experimental results conclusions are drawn about neutrino oscillations and the quantum numbers of charm-violating neutral currents. Furthermore upper limits for the momentum part of the c quark in the nucleon, and the fragmentation function for c quarks at high energies were determined. The prompt μ - μ - events are interpreted as pair production of charmed particles. Finally dimuon events induced by axions were looked for. (HSI) [de

Deep-sea Hexactinellida (Porifera) of the Weddell Sea

Science.gov (United States)

Janussen, Dorte; Tabachnick, Konstantin R.; Tendal, Ole S.

2004-07-01

New Hexactinellida from the deep Weddel Sea are described. This moderately diverse hexactinellid fauna includes 14 species belonging to 12 genera, of which five species and one subgenus are new to science: Periphragella antarctica n. sp., Holascus pseudostellatus n. sp., Caulophacus (Caulophacus) discohexactinus n. sp., C. ( Caulodiscus) brandti n. sp., C. ( Oxydiscus) weddelli n. sp., and C. ( Oxydiscus) n. subgen. So far, 20 hexactinellid species have been reported from the deep Weddell Sea, 15 are known from the northern part and 10 only from here, while 10 came from the southern area, and five of these only from there. However, this apparent high "endemism" of Antarctic hexactinellid sponges is most likely the result of severe undersampling of the deep-sea fauna. We find no reason to believe that a division between an oceanic and a more continental group of species exists. The current poor database indicates that a substantial part of the deep hexactinellid fauna of the Weddell Sea is shared with other deep-sea regions, but it does not indicate a special biogeographic relationship with any other ocean.

Detection prospects for GeV neutrinos from collisionally heated gamma-ray bursts with IceCube/DeepCore.

Science.gov (United States)

Bartos, I; Beloborodov, A M; Hurley, K; Márka, S

2013-06-14

Jet reheating via nuclear collisions has recently been proposed as the main mechanism for gamma-ray burst (GRB) emission. In addition to producing the observed gamma rays, collisional heating must generate 10-100 GeV neutrinos, implying a close relation between the neutrino and gamma-ray luminosities. We exploit this theoretical relation to make predictions for possible GRB detections by IceCube + DeepCore. To estimate the expected neutrino signal, we use the largest sample of bursts observed by the Burst and Transient Source Experiment in 1991-2000. GRB neutrinos could have been detected if IceCube + DeepCore operated at that time. Detection of 10-100 GeV neutrinos would have significant implications, shedding light on the composition of GRB jets and their Lorentz factors. This could be an important target in designing future upgrades of the IceCube + DeepCore observatory.

The Calibration Units of the KM3NeT neutrino telescope

Science.gov (United States)

Baret, B.; Keller, P.; Clark, M. Lindsey

2016-04-01

KM3NeT is a network of deep-sea neutrino telescopes to be deployed in the Mediterranean Sea that will perform neutrino astronomy and oscillation studies. It consists of three-dimensional arrays of thousands of optical modules that detect the Cherenkov light induced by charged particles resulting from the interaction of a neutrino with the surrounding medium. The performance of the neutrino telescope relies on the precise timing and positioning calibration of the detector elements. Other environmental conditions which may affect light and sound transmission, such as water temperature and salinity, must also be continuously monitored. This contribution describes the technical design of the first Calibration Unit, to be deployed on the French site as part of KM3NeT Phase 1.

The IceCube Neutrino Observatory: instrumentation and online systems

International Nuclear Information System (INIS)

Aartsen, M.G.; Ackermann, M.; Adams, J.; Aguilar, J.A.; Ansseau, I.; Ahlers, M.; Auer, R.; Baccus, J.; Barnet, S.; Ahrens, M.; Altmann, D.; Anton, G.; Andeen, K.; Anderson, T.; Archinger, M.; Argüelles, C.; Axani, S.; Auffenberg, J.; Bai, X.; Barwick, S.W.

2017-01-01

The IceCube Neutrino Observatory is a cubic-kilometer-scale high-energy neutrino detector built into the ice at the South Pole. Construction of IceCube, the largest neutrino detector built to date, was completed in 2011 and enabled the discovery of high-energy astrophysical neutrinos. We describe here the design, production, and calibration of the IceCube digital optical module (DOM), the cable systems, computing hardware, and our methodology for drilling and deployment. We also describe the online triggering and data filtering systems that select candidate neutrino and cosmic ray events for analysis. Due to a rigorous pre-deployment protocol, 98.4% of the DOMs in the deep ice are operating and collecting data. IceCube routinely achieves a detector uptime of 99% by emphasizing software stability and monitoring. Detector operations have been stable since construction was completed, and the detector is expected to operate at least until the end of the next decade.

A mechanical design for a detection unit for a deep-sea neutrino telescope

Energy Technology Data Exchange (ETDEWEB)

Berbee, E.M.; Boer Rookhuizen, H.; Heine, E.; Mul, G. [Nikhef, Science Park 105, 1098 XG Amsterdam (Netherlands); Wolf, E. de, E-mail: e.dewolf@nikhef.nl [University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands); Nikhef, Science Park 105, 1098 XG Amsterdam (Netherlands)

2013-10-11

The future KM3NeT neutrino telescope will be built on the seabed of the Mediterranean Sea at a depth between three and five kilometers. The high ambient pressure, but also the fact that the detector is hardly accessible, put severe constraints on the mechanical design of the detection units of the telescope. A detection unit is a vertical structure that supports the optical sensors of the telescope. It has a height of almost 900 m; two data cables run along the full length of the structure. The detection unit will be installed at the seabed as a compact package. Once acoustically released, it unfurls to its full length. The stability of the detection unit during unfurling and during operation is an important requirement for the mechanical design of the structure. We present the evolution of the design of the detection unit for the KM3NeT detector.

A mechanical design for a detection unit for a deep-sea neutrino telescope

International Nuclear Information System (INIS)

Berbee, E.M.; Boer Rookhuizen, H.; Heine, E.; Mul, G.; Wolf, E. de

2013-01-01

The future KM3NeT neutrino telescope will be built on the seabed of the Mediterranean Sea at a depth between three and five kilometers. The high ambient pressure, but also the fact that the detector is hardly accessible, put severe constraints on the mechanical design of the detection units of the telescope. A detection unit is a vertical structure that supports the optical sensors of the telescope. It has a height of almost 900 m; two data cables run along the full length of the structure. The detection unit will be installed at the seabed as a compact package. Once acoustically released, it unfurls to its full length. The stability of the detection unit during unfurling and during operation is an important requirement for the mechanical design of the structure. We present the evolution of the design of the detection unit for the KM3NeT detector

First biological measurements of deep-sea corals from the Red Sea.

Science.gov (United States)

Roder, C; Berumen, M L; Bouwmeester, J; Papathanassiou, E; Al-Suwailem, A; Voolstra, C R

2013-10-03

It is usually assumed that metabolic constraints restrict deep-sea corals to cold-water habitats, with 'deep-sea' and 'cold-water' corals often used as synonymous. Here we report on the first measurements of biological characters of deep-sea corals from the central Red Sea, where they occur at temperatures exceeding 20°C in highly oligotrophic and oxygen-limited waters. Low respiration rates, low calcification rates, and minimized tissue cover indicate that a reduced metabolism is one of the key adaptations to prevailing environmental conditions. We investigated four sites and encountered six species of which at least two appear to be undescribed. One species is previously reported from the Red Sea but occurs in deep cold waters outside the Red Sea raising interesting questions about presumed environmental constraints for other deep-sea corals. Our findings suggest that the present understanding of deep-sea coral persistence and resilience needs to be revisited.

First biological measurements of deep-sea corals from the Red Sea.

KAUST Repository

Roder, Cornelia

2013-10-03

It is usually assumed that metabolic constraints restrict deep-sea corals to cold-water habitats, with \\'deep-sea\\' and \\'cold-water\\' corals often used as synonymous. Here we report on the first measurements of biological characters of deep-sea corals from the central Red Sea, where they occur at temperatures exceeding 20°C in highly oligotrophic and oxygen-limited waters. Low respiration rates, low calcification rates, and minimized tissue cover indicate that a reduced metabolism is one of the key adaptations to prevailing environmental conditions. We investigated four sites and encountered six species of which at least two appear to be undescribed. One species is previously reported from the Red Sea but occurs in deep cold waters outside the Red Sea raising interesting questions about presumed environmental constraints for other deep-sea corals. Our findings suggest that the present understanding of deep-sea coral persistence and resilience needs to be revisited.

Neutrinos: Heavy water detector

International Nuclear Information System (INIS)

Anon.

1990-01-01

The proponents of the Sudbury Neutrino Observatory (SNO) received a welcome Christmas present when William Winegard, Canadian Minister for Science and Technology announced the final details of the funding for this project, totalling 48 million Canadian dollars and including contributions from the US and the UK. The SNO experiment will extend significantly the study of solar neutrinos, using some 1,000 tonnes of heavy water to be installed more than two kilometres below ground in a nickel mine at Sudbury, Ontario

Temperature impacts on deep-sea biodiversity.

Science.gov (United States)

Yasuhara, Moriaki; Danovaro, Roberto

2016-05-01

Temperature is considered to be a fundamental factor controlling biodiversity in marine ecosystems, but precisely what role temperature plays in modulating diversity is still not clear. The deep ocean, lacking light and in situ photosynthetic primary production, is an ideal model system to test the effects of temperature changes on biodiversity. Here we synthesize current knowledge on temperature-diversity relationships in the deep sea. Our results from both present and past deep-sea assemblages suggest that, when a wide range of deep-sea bottom-water temperatures is considered, a unimodal relationship exists between temperature and diversity (that may be right skewed). It is possible that temperature is important only when at relatively high and low levels but does not play a major role in the intermediate temperature range. Possible mechanisms explaining the temperature-biodiversity relationship include the physiological-tolerance hypothesis, the metabolic hypothesis, island biogeography theory, or some combination of these. The possible unimodal relationship discussed here may allow us to identify tipping points at which on-going global change and deep-water warming may increase or decrease deep-sea biodiversity. Predicted changes in deep-sea temperatures due to human-induced climate change may have more adverse consequences than expected considering the sensitivity of deep-sea ecosystems to temperature changes. © 2014 Cambridge Philosophical Society.

Neutrino oscillations with the full IceCube DeepCore detector

Energy Technology Data Exchange (ETDEWEB)

Yanez Garza, Juan Pablo [DESY, Zeuthen (Germany); Collaboration: IceCube-Collaboration

2013-07-01

The IceCube detector and its low energy extension, DeepCore, have recorded over 300,000 atmospheric neutrino events since completion almost two years ago. With an energy threshold of about 10 GeV and the possibility of observing different baselines between source and detector location, these events can be used to probe neutrino oscillations with unprecedented statistics. However, the measurement uncertainties, due to unknown properties of the detector and the medium where it stands, limit the sensitivity of such a study. The particular analysis under discussion is a special attempt to diminish the impact of systematic uncertainties while keeping a large high quality neutrino sample. The tools developed for it, as well as the current status of the analysis are presented.

Deep-sea coral research and technology program: Alaska deep-sea coral and sponge initiative final report

Science.gov (United States)

Rooper, Chris; Stone, Robert P.; Etnoyer, Peter; Conrath, Christina; Reynolds, Jennifer; Greene, H. Gary; Williams, Branwen; Salgado, Enrique; Morrison, Cheryl L.; Waller, Rhian G.; Demopoulos, Amanda W.J.

2017-01-01

Deep-sea coral and sponge ecosystems are widespread throughout most of Alaska’s marine waters. In some places, such as the central and western Aleutian Islands, deep-sea coral and sponge resources can be extremely diverse and may rank among the most abundant deep-sea coral and sponge communities in the world. Many different species of fishes and invertebrates are associated with deep-sea coral and sponge communities in Alaska. Because of their biology, these benthic invertebrates are potentially impacted by climate change and ocean acidification. Deepsea coral and sponge ecosystems are also vulnerable to the effects of commercial fishing activities. Because of the size and scope of Alaska’s continental shelf and slope, the vast majority of the area has not been visually surveyed for deep-sea corals and sponges. NOAA’s Deep Sea Coral Research and Technology Program (DSCRTP) sponsored a field research program in the Alaska region between 2012–2015, referred to hereafter as the Alaska Initiative. The priorities for Alaska were derived from ongoing data needs and objectives identified by the DSCRTP, the North Pacific Fishery Management Council (NPFMC), and Essential Fish Habitat-Environmental Impact Statement (EFH-EIS) process.This report presents the results of 15 projects conducted using DSCRTP funds from 2012-2015. Three of the projects conducted as part of the Alaska deep-sea coral and sponge initiative included dedicated at-sea cruises and fieldwork spread across multiple years. These projects were the eastern Gulf of Alaska Primnoa pacifica study, the Aleutian Islands mapping study, and the Gulf of Alaska fish productivity study. In all, there were nine separate research cruises carried out with a total of 109 at-sea days conducting research. The remaining projects either used data and samples collected by the three major fieldwork projects or were piggy-backed onto existing research programs at the Alaska Fisheries Science Center (AFSC).

Status of the KM3NeT project

International Nuclear Information System (INIS)

Katz, U.F.

2009-01-01

KM3NeT is a future research infrastructure in the Mediterranean Sea, hosting a cubic-kilometre scale neutrino telescope and nodes for associated sciences such as marine biology, oceanology and geophysics. The status of the KM3NeT project and the progress made in the EU-funded Design Study is reviewed. Some physics studies indicating the sensitivity of the KM3NeT neutrino telescope are highlighted and selected major technical design options to be further pursued are described. Finally, the remaining steps towards construction of KM3NeT will be discussed. This document reflects the status of the KM3NeT Conceptual Design Report (CDR), which has been presented to the public for the first time at the VLVnT08 Workshop.

Extreme Longevity in Proteinaceous Deep-Sea Corals

Energy Technology Data Exchange (ETDEWEB)

Roark, E B; Guilderson, T P; Dunbar, R B; Fallon, S J; Mucciarone, D A

2009-02-09

Deep-sea corals are found on hard substrates on seamounts and continental margins world-wide at depths of 300 to {approx}3000 meters. Deep-sea coral communities are hotspots of deep ocean biomass and biodiversity, providing critical habitat for fish and invertebrates. Newly applied radiocarbon age date from the deep water proteinaceous corals Gerardia sp. and Leiopathes glaberrima show that radial growth rates are as low as 4 to 35 {micro}m yr{sup -1} and that individual colony longevities are on the order of thousands of years. The management and conservation of deep sea coral communities is challenged by their commercial harvest for the jewelry trade and damage caused by deep water fishing practices. In light of their unusual longevity, a better understanding of deep sea coral ecology and their interrelationships with associated benthic communities is needed to inform coherent international conservation strategies for these important deep-sea ecosystems.

A large spherical HPD for a novel deep-sea neutrino experiment

International Nuclear Information System (INIS)

Ball, A.E.; Braem, A.; Camilleri, L.; Catinaccio, A.; Chelkov, G.; Dydak, F.; Elagin, A.; Frandsen, P.; Grant, A.; Gostkin, M.; Guskov, A.; Joram, C.; Krumshteyn, Z.; Lustermann, W.; Postema, H.; Price, M.; Rovelli, T.; Schinzel, D.; Seguinot, J.; Valenti, G.; Voss, R.; Wotschack, J.; Zhemchugov, A.

2005-01-01

An underwater neutrino experiment has been proposed which provides precise measurements of the neutrino mixing parameters θ 23 and Δm 23 2 and permits an increase of sensitivity for the small angle θ 13 by more than one order of magnitude. A Cherenkov detector of about 1.5Mt active mass, deployed in the Gulf of Taranto, utilizes the CNGS beam in off-axis configuration which represents an essentially mono-energetic source of muon neutrinos. A unique feature of the experiment is the possibility to move the detector and therefore exploit different baselines around 1200km where the oscillation pattern is fully developed. The conceptual detector design consists of O(30,000) large area and acceptance photosensors arranged in a matrix of ∼300x300m 2 size. Hybrid photon detectors are considered as promising candidates as they provide clean signal characteristics and uniform collection efficiency. We discuss the design and expected performance of a large spherical HPD with 380mm diameter, which is housed in a high-pressure glass container. A scaled prototype HPD of 208mm diameter is currently under development using the existing CERN HPD facility

Radiative corrections to neutrino deep inelastic scattering revisited

International Nuclear Information System (INIS)

Arbuzov, Andrej B.; Bardin, Dmitry Yu.; Kalinovskaya, Lidia V.

2005-01-01

Radiative corrections to neutrino deep inelastic scattering are revisited. One-loop electroweak corrections are re-calculated within the automatic SANC system. Terms with mass singularities are treated including higher order leading logarithmic corrections. Scheme dependence of corrections due to weak interactions is investigated. The results are implemented into the data analysis of the NOMAD experiment. The present theoretical accuracy in description of the process is discussed

Search for indications of the neutrino mass hierarchy using IceCube/DeepCore

Energy Technology Data Exchange (ETDEWEB)

Leuermann, Martin; Vehring, Markus; Wallraff, Marius; Wiebusch, Christopher [III. Physikalisches Institut B, RWTH Aachen (Germany); Collaboration: IceCube-Collaboration

2016-07-01

In 2015, the Nobel prize in physics was awarded for ''the discovery of neutrino oscillations, which shows that neutrinos have mass'', showing the high relevance of neutrino masses for modern particle physics. However, the ordering of the three neutrino masses is still unknown and is often referred to as neutrino mass hierarchy. Its measurement is a major goal for future experiments. One strategy is to measure matter effects in the oscillation pattern of atmospheric neutrinos e.g. as proposed for the PINGU extension of the IceCube neutrino observatory. Already now, the IceCube/DeepCore detector at the Geographic South Pole can be used to search for this signature. In this talk, we present an analysis based on data taken between 2011 and 2015. Due to recent improvements in the detector's reconstruction performance and the quality of the data selection, a measurement on the significance level of 1 sigma is expected.

KM3NeT/ARCA sensitivity and discovery potential for neutrino point-like sources

Directory of Open Access Journals (Sweden)

Trovato A.

2016-01-01

Full Text Available KM3NeT is a large research infrastructure with a network of deep-sea neutrino telescopes in the abyss of the Mediterranean Sea. Of these, the KM3NeT/ARCA detector, installed in the KM3NeT-It node of the network, is optimised for studying high-energy neutrinos of cosmic origin. Sensitivities to galactic sources such as the supernova remnant RXJ1713.7-3946 and the pulsar wind nebula Vela X are presented as well as sensitivities to a generic point source with an E−2 spectrum which represents an approximation for the spectrum of extragalactic candidate neutrino sources.

First biological measurements of deep-sea corals from the Red Sea

OpenAIRE

C. Roder; M. L. Berumen; J. Bouwmeester; E. Papathanassiou; A. Al-Suwailem; C. R. Voolstra

2013-01-01

It is usually assumed that metabolic constraints restrict deep-sea corals to cold-water habitats, with ?deep-sea? and ?cold-water? corals often used as synonymous. Here we report on the first measurements of biological characters of deep-sea corals from the central Red Sea, where they occur at temperatures exceeding 20?C in highly oligotrophic and oxygen-limited waters. Low respiration rates, low calcification rates, and minimized tissue cover indicate that a reduced metabolism is one of the ...

Search for nonstandard neutrino interactions with IceCube DeepCore

Science.gov (United States)

Aartsen, M. G.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Ahrens, M.; Al Samarai, I.; Altmann, D.; Andeen, K.; Anderson, T.; Ansseau, I.; Anton, G.; Argüelles, C.; Auffenberg, J.; Axani, S.; Bagherpour, H.; Bai, X.; Barron, J. P.; Barwick, S. W.; Baum, V.; Bay, R.; Beatty, J. J.; Becker Tjus, J.; Becker, K.-H.; BenZvi, S.; Berley, D.; Bernardini, E.; Besson, D. Z.; Binder, G.; Bindig, D.; Blaufuss, E.; Blot, S.; Bohm, C.; Börner, M.; Bos, F.; Bose, D.; Böser, S.; Botner, O.; Bourbeau, E.; Bourbeau, J.; Bradascio, F.; Braun, J.; Brayeur, L.; Brenzke, M.; Bretz, H.-P.; Bron, S.; Brostean-Kaiser, J.; Burgman, A.; Carver, T.; Casey, J.; Casier, M.; Cheung, E.; Chirkin, D.; Christov, A.; Clark, K.; Classen, L.; Coenders, S.; Collin, G. H.; Conrad, J. M.; Cowen, D. F.; Cross, R.; Day, M.; de André, J. P. A. M.; De Clercq, C.; DeLaunay, J. J.; Dembinski, H.; De Ridder, S.; Desiati, P.; de Vries, K. D.; de Wasseige, G.; de With, M.; DeYoung, T.; Díaz-Vélez, J. C.; di Lorenzo, V.; Dujmovic, H.; Dumm, J. P.; Dunkman, M.; Dvorak, E.; Eberhardt, B.; Ehrhardt, T.; Eichmann, B.; Eller, P.; Evenson, P. A.; Fahey, S.; Fazely, A. R.; Felde, J.; Filimonov, K.; Finley, C.; Flis, S.; Franckowiak, A.; Friedman, E.; Fuchs, T.; Gaisser, T. K.; Gallagher, J.; Gerhardt, L.; Ghorbani, K.; Giang, W.; Glauch, T.; Glüsenkamp, T.; Goldschmidt, A.; Gonzalez, J. G.; Grant, D.; Griffith, Z.; Haack, C.; Hallgren, A.; Halzen, F.; Hanson, K.; Hebecker, D.; Heereman, D.; Helbing, K.; Hellauer, R.; Hickford, S.; Hignight, J.; Hill, G. C.; Hoffman, K. D.; Hoffmann, R.; Hokanson-Fasig, B.; Hoshina, K.; Huang, F.; Huber, M.; Hultqvist, K.; Hünnefeld, M.; In, S.; Ishihara, A.; Jacobi, E.; Japaridze, G. S.; Jeong, M.; Jero, K.; Jones, B. J. P.; Kalaczynski, P.; Kang, W.; Kappes, A.; Karg, T.; Karle, A.; Katz, U.; Kauer, M.; Keivani, A.; Kelley, J. L.; Kheirandish, A.; Kim, J.; Kim, M.; Kintscher, T.; Kirby, C.; Kiryluk, J.; Kittler, T.; Klein, S. R.; Kohnen, G.; Koirala, R.; Kolanoski, H.; Köpke, L.; Kopper, C.; Kopper, S.; Koschinsky, J. P.; Koskinen, D. J.; Kowalski, M.; Krings, K.; Kroll, M.; Krückl, G.; Kunnen, J.; Kunwar, S.; Kurahashi, N.; Kuwabara, T.; Kyriacou, A.; Labare, M.; Lanfranchi, J. L.; Larson, M. J.; Lauber, F.; Lennarz, D.; Lesiak-Bzdak, M.; Leuermann, M.; Liu, Q. R.; Lu, L.; Lünemann, J.; Luszczak, W.; Madsen, J.; Maggi, G.; Mahn, K. B. M.; Mancina, S.; Maruyama, R.; Mase, K.; Maunu, R.; McNally, F.; Meagher, K.; Medici, M.; Meier, M.; Menne, T.; Merino, G.; Meures, T.; Miarecki, S.; Micallef, J.; Momenté, G.; Montaruli, T.; Moore, R. W.; Moulai, M.; Nahnhauer, R.; Nakarmi, P.; Naumann, U.; Neer, G.; Niederhausen, H.; Nowicki, S. C.; Nygren, D. R.; Obertacke Pollmann, A.; Olivas, A.; O'Murchadha, A.; Palczewski, T.; Pandya, H.; Pankova, D. V.; Peiffer, P.; Pepper, J. A.; Pérez de los Heros, C.; Pieloth, D.; Pinat, E.; Plum, M.; Price, P. B.; Przybylski, G. T.; Raab, C.; Rädel, L.; Rameez, M.; Rawlins, K.; Rea, I. C.; Reimann, R.; Relethford, B.; Relich, M.; Resconi, E.; Rhode, W.; Richman, M.; Robertson, S.; Rongen, M.; Rott, C.; Ruhe, T.; Ryckbosch, D.; Rysewyk, D.; Sälzer, T.; Sanchez Herrera, S. E.; Sandrock, A.; Sandroos, J.; Santander, M.; Sarkar, S.; Sarkar, S.; Satalecka, K.; Schlunder, P.; Schmidt, T.; Schneider, A.; Schoenen, S.; Schöneberg, S.; Schumacher, L.; Seckel, D.; Seunarine, S.; Soedingrekso, J.; Soldin, D.; Song, M.; Spiczak, G. M.; Spiering, C.; Stachurska, J.; Stamatikos, M.; Stanev, T.; Stasik, A.; Stettner, J.; Steuer, A.; Stezelberger, T.; Stokstad, R. G.; Stößl, A.; Strotjohann, N. L.; Stuttard, T.; Sullivan, G. W.; Sutherland, M.; Taboada, I.; Tatar, J.; Tenholt, F.; Ter-Antonyan, S.; Terliuk, A.; Tešić, G.; Tilav, S.; Toale, P. A.; Tobin, M. N.; Toscano, S.; Tosi, D.; Tselengidou, M.; Tung, C. F.; Turcati, A.; Turley, C. F.; Ty, B.; Unger, E.; Usner, M.; Vandenbroucke, J.; Van Driessche, W.; van Eijndhoven, N.; Vanheule, S.; van Santen, J.; Vehring, M.; Vogel, E.; Vraeghe, M.; Walck, C.; Wallace, A.; Wallraff, M.; Wandler, F. D.; Wandkowsky, N.; Waza, A.; Weaver, C.; Weiss, M. J.; Wendt, C.; Werthebach, J.; Westerhoff, S.; Whelan, B. J.; Wiebe, K.; Wiebusch, C. H.; Wille, L.; Williams, D. R.; Wills, L.; Wolf, M.; Wood, J.; Wood, T. R.; Woolsey, E.; Woschnagg, K.; Xu, D. L.; Xu, X. W.; Xu, Y.; Yanez, J. P.; Yodh, G.; Yoshida, S.; Yuan, T.; Zoll, M.; IceCube Collaboration

2018-04-01

As atmospheric neutrinos propagate through the Earth, vacuumlike oscillations are modified by Standard Model neutral- and charged-current interactions with electrons. Theories beyond the Standard Model introduce heavy, TeV-scale bosons that can produce nonstandard neutrino interactions. These additional interactions may modify the Standard Model matter effect producing a measurable deviation from the prediction for atmospheric neutrino oscillations. The result described in this paper constrains nonstandard interaction parameters, building upon a previous analysis of atmospheric muon-neutrino disappearance with three years of IceCube DeepCore data. The best fit for the muon to tau flavor changing term is ɛμ τ=-0.0005 , with a 90% C.L. allowed range of -0.0067 <ɛμ τ<0.0081 . This result is more restrictive than recent limits from other experiments for ɛμ τ. Furthermore, our result is complementary to a recent constraint on ɛμ τ using another publicly available IceCube high-energy event selection. Together, they constitute the world's best limits on nonstandard interactions in the μ -τ sector.

Progress toward a Km-scale neutrino detector in the deep ocean

Energy Technology Data Exchange (ETDEWEB)

Stokstad, R.G.

1997-11-01

The best particles for observing distant objects are photons and neutrinos. Because of the neutrino`s weak interaction cross section, detectors suitable for astronomy must be very large and well shielded from cosmic rays. Eventually, a detector with the order of a square km of effective area will be needed for systematic observations of distant point sources such as active galactic nuclei. Prototype detectors are currently being developed at several sites in the ocean, at Lake Baikal, and in Antarctica. This talk summarizes the status of the projects that use the deep ocean for the detector medium and shielding: DUMAND, NESTOR and ANTARES. Technical developments will be needed for a future km-scale detector; progress on one of these, a digital electronic system, is also described.

Taxonomic research on deep-sea macrofauna in the South China Sea using the Chinese deep-sea submersible Jiaolong.

Science.gov (United States)

Li, Xinzheng

2017-07-01

This paper reviews the taxonomic and biodiversity studies of deep-sea invertebrates in the South China Sea based on the samples collected by the Chinese manned deep-sea submersible Jiaolong. To date, 6 new species have been described, including the sponges Lophophysema eversa, Saccocalyx microhexactin and Semperella jiaolongae as well as the crustaceans Uroptychus jiaolongae, Uroptychus spinulosus and Globospongicola jiaolongi; some newly recorded species from the South China Sea have also been reported. The Bathymodiolus platifrons-Shinkaia crosnieri deep-sea cold seep community has been reported by Li (2015), as has the mitochondrial genome of the glass sponge L. eversa by Zhang et al. (2016). The population structures of two dominant species, the shrimp Shinkaia crosnieri and the mussel Bathymodiolus platifrons, from the cold seep Bathymodiolus platifrons-Shinkaia crosnieri community in the South China Sea and the hydrothermal vents in the Okinawa Trough, were compared using molecular analysis. The systematic position of the shrimp genus Globospongicola was discussed based on 16S rRNA gene sequences. © 2017 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Acoustic detection of high energy neutrinos in sea water: status and prospects

Directory of Open Access Journals (Sweden)

Lahmann Robert

2017-01-01

Full Text Available The acoustic neutrino detection technique is a promising approach for future large-scale detectors with the aim of measuring the small expected flux of neutrinos at energies in the EeV-range and above. The technique is based on the thermo-acoustic model, which implies that the energy deposition by a particle cascade – resulting from a neutrino interaction in a medium with suitable thermal and acoustic properties – leads to a local heating and a subsequent characteristic pressure pulse that propagates in the surrounding medium. Current or recent test setups for acoustic neutrino detection have either been add-ons to optical neutrino telescopes or have been using acoustic arrays built for other purposes, typically for military use. While these arrays have been too small to derive competitive limits on neutrino fluxes, they allowed for detailed studies of the experimental technique. With the advent of the research infrastructure KM3NeT in the Mediterranean Sea, new possibilities will arise for acoustic neutrino detection. In this article, results from the “first generation” of acoustic arrays will be summarized and implications for the future of acoustic neutrino detection will be discussed.

Revealing Holobiont Structure and Function of Three Red Sea Deep-Sea Corals

KAUST Repository

Yum, Lauren

2014-12-01

Deep-sea corals have long been regarded as cold-water coral; however a reevaluation of their habitat limitations has been suggested after the discovery of deep-sea coral in the Red Sea where temperatures exceed 20˚C. To gain further insight into the biology of deep-sea corals at these temperatures, the work in this PhD employed a holotranscriptomic approach, looking at coral animal host and bacterial symbiont gene expression in Dendrophyllia sp., Eguchipsammia fistula, and Rhizotrochus sp. sampled from the deep Red Sea. Bacterial community composition was analyzed via amplicon-based 16S surveys and cultured bacterial strains were subjected to bioprospecting in order to gauge the pharmaceutical potential of coralassociated microbes. Coral host transcriptome data suggest that coral can employ mitochondrial hypometabolism, anaerobic glycolysis, and surface cilia to enhance mass transport rates to manage the low oxygen and highly oligotrophic Red Sea waters. In the microbial community associated with these corals, ribokinases and retron-type reverse transcriptases are abundantly expressed. In its first application to deep-sea coral associated microbial communities, 16S-based next-generation sequencing found that a single operational taxonomic unit can comprise the majority of sequence reads and that a large number of low abundance populations are present, which cannot be visualized with first generation sequencing. Bioactivity testing of selected bacterial isolates was surveyed over 100 cytological parameters with high content screening, covering several major organelles and key proteins involved in a variety of signaling cascades. Some of these cytological profiles were similar to those of several reference pharmacologically active compounds, which suggest that the bacteria isolates produce compounds with similar mechanisms of action as the reference compounds. The sum of this work offers several mechanisms by which Red Sea deep-sea corals cope with environmental

Authigenic gypsum in a deep sea core from Southeastern Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

Guptha, M.V.S.

Authigenic gypsum has been encountered in a deep sea core RC9-157 from the southeastern Arabian Sea at a depth of 4111 m which is a zone of lysocline. The formation of gypsum in the deep sea region is attributed to the prevailing sulphate rich...

Study of data filtering algorithms for the KM3NeT neutrino telescope

Energy Technology Data Exchange (ETDEWEB)

Herold, B., E-mail: Bjoern.Herold@physik.uni-erlangen.d [Erlangen Centre for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany); Seitz, T., E-mail: Thomas.Seitz@physik.uni-erlangen.d [Erlangen Centre for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany); Shanidze, R., E-mail: shanidze@physik.uni-erlangen.d [Erlangen Centre for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany)

2011-01-21

The photomultiplier signals above a defined threshold (hits) are the main data collected from the KM3NeT neutrino telescope. The neutrino and muon events will be reconstructed from these signals. However, in the deep sea the dominant source of hits are the decays of {sup 40}K isotope and marine fauna bioluminescence. The selection of neutrino and muon events requires the implementation of fast and efficient data filtering algorithms for the reduction of accidental background event rates. A possible data filtering scheme for the KM3NeT neutrino telescope is discussed in the paper.

Deep-sea mud in the Pacific Ocean as a potential resource for rare-earth elements

Science.gov (United States)

Kato, Yasuhiro; Fujinaga, Koichiro; Nakamura, Kentaro; Takaya, Yutaro; Kitamura, Kenichi; Ohta, Junichiro; Toda, Ryuichi; Nakashima, Takuya; Iwamori, Hikaru

2011-08-01

World demand for rare-earth elements and the metal yttrium--which are crucial for novel electronic equipment and green-energy technologies--is increasing rapidly. Several types of seafloor sediment harbour high concentrations of these elements. However, seafloor sediments have not been regarded as a rare-earth element and yttrium resource, because data on the spatial distribution of these deposits are insufficient. Here, we report measurements of the elemental composition of over 2,000 seafloor sediments, sampled at depth intervals of around one metre, at 78 sites that cover a large part of the Pacific Ocean. We show that deep-sea mud contains high concentrations of rare-earth elements and yttrium at numerous sites throughout the eastern South and central North Pacific. We estimate that an area of just one square kilometre, surrounding one of the sampling sites, could provide one-fifth of the current annual world consumption of these elements. Uptake of rare-earth elements and yttrium by mineral phases such as hydrothermal iron-oxyhydroxides and phillipsite seems to be responsible for their high concentration. We show that rare-earth elements and yttrium are readily recovered from the mud by simple acid leaching, and suggest that deep-sea mud constitutes a highly promising huge resource for these elements.

Nuclear corrections in neutrino deep inelastic scattering and the extraction of the strange quark distribution

International Nuclear Information System (INIS)

Boros, C.

1999-01-01

Recent measurement of the structure function F 2 υ in neutrino deep inelastic scattering allows us to compare structure functions measured in neutrino and charged lepton scattering for the first time with reasonable precision. The comparison between neutrino and muon structure functions made by the CCFR Collaboration indicates that there is a discrepancy between these structure functions at small Bjorken x values. In this talk I examine two effects which might account for this experimental discrepancy: nuclear shadowing corrections for neutrinos and contributions from strange and anti-strange quarks. Copyright (1999) World Scientific Publishing Co. Pte. Ltd

Geo-neutrino Observation

International Nuclear Information System (INIS)

Dye, S. T.; Alderman, M.; Batygov, M.; Learned, J. G.; Matsuno, S.; Mahoney, J. M.; Pakvasa, S.; Rosen, M.; Smith, S.; Varner, G.; McDonough, W. F.

2009-01-01

Observations of geo-neutrinos measure radiogenic heat production within the earth, providing information on the thermal history and dynamic processes of the mantle. Two detectors currently observe geo-neutrinos from underground locations. Other detection projects in various stages of development include a deep ocean observatory. This paper presents the current status of geo-neutrino observation and describes the scientific capabilities of the deep ocean observatory, with emphasis on geology and neutrino physics.

Measurement of partonic nuclear effects in deep-inelastic neutrino scattering using MINERvA

Science.gov (United States)

Mousseau, J.; Wospakrik, M.; Aliaga, L.; Altinok, O.; Bellantoni, L.; Bercellie, A.; Betancourt, M.; Bodek, A.; Bravar, A.; Budd, H.; Cai, T.; Carneiro, M. F.; Christy, M. E.; Chvojka, J.; da Motta, H.; Devan, J.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Felix, J.; Fields, L.; Fine, R.; Gago, A. M.; Galindo, R.; Gallagher, H.; Ghosh, A.; Golan, T.; Gran, R.; Harris, D. A.; Higuera, A.; Hurtado, K.; Kiveni, M.; Kleykamp, J.; Kordosky, M.; Le, T.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; Martinez Caicedo, D. A.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Messerly, B.; Miller, J.; Mislivec, A.; Morfín, J. G.; Naples, D.; Nelson, J. K.; Norrick, A.; Nuruzzaman; Osta, J.; Paolone, V.; Park, J.; Patrick, C. E.; Perdue, G. N.; Rakotondravohitra, L.; Ramirez, M. A.; Ransome, R. D.; Ray, H.; Ren, L.; Rimal, D.; Rodrigues, P. A.; Ruterbories, D.; Schellman, H.; Schmitz, D. W.; Solano Salinas, C. J.; Tagg, N.; Tice, B. G.; Valencia, E.; Walton, T.; Wolcott, J.; Zavala, G.; Zhang, D.; Minerν A Collaboration

2016-04-01

The MINERvA Collaboration reports a novel study of neutrino-nucleus charged-current deep inelastic scattering (DIS) using the same neutrino beam incident on targets of polystyrene, graphite, iron, and lead. Results are presented as ratios of C, Fe, and Pb to CH. The ratios of total DIS cross sections as a function of neutrino energy and flux-integrated differential cross sections as a function of the Bjorken scaling variable x are presented in the neutrino-energy range of 5-50 GeV. Based on the predictions of charged-lepton scattering ratios, good agreement is found between the data and prediction at medium x and low neutrino energy. However, the ratios appear to be below predictions in the vicinity of the nuclear shadowing region, x <0.1 . This apparent deficit, reflected in the DIS cross-section ratio at high Eν, is consistent with previous MINERvA observations [B. Tice et al. (MINERvA Collaboration), Phys. Rev. Lett. 112, 231801 (2014).] and with the predicted onset of nuclear shadowing with the axial-vector current in neutrino scattering.

Deep-sea geohazards in the South China Sea

Science.gov (United States)

Wu, Shiguo; Wang, Dawei; Völker, David

2018-02-01

Various geological processes and features that might inflict hazards identified in the South China Sea by using new technologies and methods. These features include submarine landslides, pockmark fields, shallow free gas, gas hydrates, mud diapirs and earthquake tsunami, which are widely distributed in the continental slope and reefal islands of the South China Sea. Although the study and assessment of geohazards in the South China Sea came into operation only recently, advances in various aspects are evolving at full speed to comply with National Marine Strategy and `the Belt and Road' Policy. The characteristics of geohazards in deep-water seafloor of the South China Sea are summarized based on new scientific advances. This progress is aimed to aid ongoing deep-water drilling activities and decrease geological risks in ocean development.

U.V. repair in deep-sea bacteria

International Nuclear Information System (INIS)

Lutz, L.; Yayanos, A.A.

1986-01-01

Exposure of cells to light of less than 320 nanometers wavelengths may lead to lethal lesions and perhaps carcinogenesis. Many organisms have evolved mechanisms to repair U.V. light-induced damage. Organisms such as deep-sea bacteria are presumably never exposed to U.V. light and perhaps occasionally to visible from bioluminescence. Thus, the repair of U.V. damage in deep-sea bacterial DNA might be inefficient and repair by photoreactivation unlikely. The bacteria utilized in this investigation are temperature sensitive and barophilic. Four deep-sea isolates were chosen for this study: PE-36 from 3584 m, CNPT-3 from 5782 m, HS-34 from 5682 m, and MT-41 from 10,476 m, all are from the North Pacific ocean. The deep-sea extends from 1100 m to depths greater than 7000 m. It is a region of relatively uniform conditions. The temperature ranges from 5 to -1 0 C. There is no solar light in the deep-sea. Deep-sea bacteria are sensitive to U.V. light; in fact more sensitive than a variety of terrestrial and sea-surface bacteria. All four isolates demonstrate thymine dimer repair. Photoreactivation was observed in only MT-41. The other strains from shallower depths displayed no photoreactivation. The presence of DNA sequences homologous to the rec A, uvr A, B, and C and phr genes of E. coli have been examined by Southern hybridization techniques

In Brief: Deep-sea observatory

Science.gov (United States)

Showstack, Randy

2008-11-01

The first deep-sea ocean observatory offshore of the continental United States has begun operating in the waters off central California. The remotely operated Monterey Accelerated Research System (MARS) will allow scientists to monitor the deep sea continuously. Among the first devices to be hooked up to the observatory are instruments to monitor earthquakes, videotape deep-sea animals, and study the effects of acidification on seafloor animals. ``Some day we may look back at the first packets of data streaming in from the MARS observatory as the equivalent of those first words spoken by Alexander Graham Bell: `Watson, come here, I need you!','' commented Marcia McNutt, president and CEO of the Monterey Bay Aquarium Research Institute, which coordinated construction of the observatory. For more information, see http://www.mbari.org/news/news_releases/2008/mars-live/mars-live.html.

Measurement of Atmospheric Neutrino Oscillations at 6-56 GeV with IceCube DeepCore

Science.gov (United States)

Aartsen, M. G.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Ahrens, M.; Al Samarai, I.; Altmann, D.; Andeen, K.; Anderson, T.; Ansseau, I.; Anton, G.; Argüelles, C.; Auffenberg, J.; Axani, S.; Bagherpour, H.; Bai, X.; Barron, J. P.; Barwick, S. W.; Baum, V.; Bay, R.; Beatty, J. J.; Becker Tjus, J.; Becker, K.-H.; BenZvi, S.; Berley, D.; Bernardini, E.; Besson, D. Z.; Binder, G.; Bindig, D.; Blaufuss, E.; Blot, S.; Bohm, C.; Börner, M.; Bos, F.; Bose, D.; Böser, S.; Botner, O.; Bourbeau, J.; Bradascio, F.; Braun, J.; Brayeur, L.; Brenzke, M.; Bretz, H.-P.; Bron, S.; Brostean-Kaiser, J.; Burgman, A.; Carver, T.; Casey, J.; Casier, M.; Cheung, E.; Chirkin, D.; Christov, A.; Clark, K.; Classen, L.; Coenders, S.; Collin, G. H.; Conrad, J. M.; Cowen, D. F.; Cross, R.; Day, M.; de André, J. P. A. M.; De Clercq, C.; DeLaunay, J. J.; Dembinski, H.; De Ridder, S.; Desiati, P.; de Vries, K. D.; de Wasseige, G.; de With, M.; DeYoung, T.; Díaz-Vélez, J. C.; di Lorenzo, V.; Dujmovic, H.; Dumm, J. P.; Dunkman, M.; Eberhardt, B.; Ehrhardt, T.; Eichmann, B.; Eller, P.; Evenson, P. A.; Fahey, S.; Fazely, A. R.; Felde, J.; Filimonov, K.; Finley, C.; Flis, S.; Franckowiak, A.; Friedman, E.; Fuchs, T.; Gaisser, T. K.; Gallagher, J.; Gerhardt, L.; Ghorbani, K.; Giang, W.; Glauch, T.; Glüsenkamp, T.; Goldschmidt, A.; Gonzalez, J. G.; Grant, D.; Griffith, Z.; Haack, C.; Hallgren, A.; Halzen, F.; Hanson, K.; Hebecker, D.; Heereman, D.; Helbing, K.; Hellauer, R.; Hickford, S.; Hignight, J.; Hill, G. C.; Hoffman, K. D.; Hoffmann, R.; Hokanson-Fasig, B.; Hoshina, K.; Huang, F.; Huber, M.; Hultqvist, K.; Hünnefeld, M.; In, S.; Ishihara, A.; Jacobi, E.; Japaridze, G. S.; Jeong, M.; Jero, K.; Jones, B. J. P.; Kalaczynski, P.; Kang, W.; Kappes, A.; Karg, T.; Karle, A.; Katz, U.; Kauer, M.; Keivani, A.; Kelley, J. L.; Kheirandish, A.; Kim, J.; Kim, M.; Kintscher, T.; Kiryluk, J.; Kittler, T.; Klein, S. R.; Kohnen, G.; Koirala, R.; Kolanoski, H.; Köpke, L.; Kopper, C.; Kopper, S.; Koschinsky, J. P.; Koskinen, D. J.; Kowalski, M.; Krings, K.; Kroll, M.; Krückl, G.; Kunnen, J.; Kunwar, S.; Kurahashi, N.; Kuwabara, T.; Kyriacou, A.; Labare, M.; Lanfranchi, J. L.; Larson, M. J.; Lauber, F.; Lennarz, D.; Lesiak-Bzdak, M.; Leuermann, M.; Liu, Q. R.; Lu, L.; Lünemann, J.; Luszczak, W.; Madsen, J.; Maggi, G.; Mahn, K. B. M.; Mancina, S.; Maruyama, R.; Mase, K.; Maunu, R.; McNally, F.; Meagher, K.; Medici, M.; Meier, M.; Menne, T.; Merino, G.; Meures, T.; Miarecki, S.; Micallef, J.; Momenté, G.; Montaruli, T.; Moore, R. W.; Moulai, M.; Nahnhauer, R.; Nakarmi, P.; Naumann, U.; Neer, G.; Niederhausen, H.; Nowicki, S. C.; Nygren, D. R.; Obertacke Pollmann, A.; Olivas, A.; O'Murchadha, A.; Palczewski, T.; Pandya, H.; Pankova, D. V.; Peiffer, P.; Pepper, J. A.; Pérez de los Heros, C.; Pieloth, D.; Pinat, E.; Plum, M.; Price, P. B.; Przybylski, G. T.; Raab, C.; Rädel, L.; Rameez, M.; Rawlins, K.; Rea, I. C.; Reimann, R.; Relethford, B.; Relich, M.; Resconi, E.; Rhode, W.; Richman, M.; Robertson, S.; Rongen, M.; Rott, C.; Ruhe, T.; Ryckbosch, D.; Rysewyk, D.; Sälzer, T.; Sanchez Herrera, S. E.; Sandrock, A.; Sandroos, J.; Sarkar, S.; Sarkar, S.; Satalecka, K.; Schlunder, P.; Schmidt, T.; Schneider, A.; Schoenen, S.; Schöneberg, S.; Schumacher, L.; Seckel, D.; Seunarine, S.; Soedingrekso, J.; Soldin, D.; Song, M.; Spiczak, G. M.; Spiering, C.; Stachurska, J.; Stamatikos, M.; Stanev, T.; Stasik, A.; Stettner, J.; Steuer, A.; Stezelberger, T.; Stokstad, R. G.; Stößl, A.; Strotjohann, N. L.; Sullivan, G. W.; Sutherland, M.; Taboada, I.; Tatar, J.; Tenholt, F.; Ter-Antonyan, S.; Terliuk, A.; Tešić, G.; Tilav, S.; Toale, P. A.; Tobin, M. N.; Toscano, S.; Tosi, D.; Tselengidou, M.; Tung, C. F.; Turcati, A.; Turley, C. F.; Ty, B.; Unger, E.; Usner, M.; Vandenbroucke, J.; Van Driessche, W.; van Eijndhoven, N.; Vanheule, S.; van Santen, J.; Vehring, M.; Vogel, E.; Vraeghe, M.; Walck, C.; Wallace, A.; Wallraff, M.; Wandler, F. D.; Wandkowsky, N.; Waza, A.; Weaver, C.; Weiss, M. J.; Wendt, C.; Werthebach, J.; Westerhoff, S.; Whelan, B. J.; Wiebe, K.; Wiebusch, C. H.; Wille, L.; Williams, D. R.; Wills, L.; Wolf, M.; Wood, J.; Wood, T. R.; Woolsey, E.; Woschnagg, K.; Xu, D. L.; Xu, X. W.; Xu, Y.; Yanez, J. P.; Yodh, G.; Yoshida, S.; Yuan, T.; Zoll, M.; IceCube Collaboration

2018-02-01

We present a measurement of the atmospheric neutrino oscillation parameters using three years of data from the IceCube Neutrino Observatory. The DeepCore infill array in the center of IceCube enables the detection and reconstruction of neutrinos produced by the interaction of cosmic rays in Earth's atmosphere at energies as low as ˜5 GeV . That energy threshold permits measurements of muon neutrino disappearance, over a range of baselines up to the diameter of the Earth, probing the same range of L /Eν as long-baseline experiments but with substantially higher-energy neutrinos. This analysis uses neutrinos from the full sky with reconstructed energies from 5.6 to 56 GeV. We measure Δ m322=2.31-0.13+0.11×10-3 eV2 and sin2θ23=0.5 1-0.09+0.07, assuming normal neutrino mass ordering. These results are consistent with, and of similar precision to, those from accelerator- and reactor-based experiments.

Sea-level and deep-sea-temperature variability over the past 5.3 million years.

Science.gov (United States)

Rohling, E J; Foster, G L; Grant, K M; Marino, G; Roberts, A P; Tamisiea, M E; Williams, F

2014-04-24

Ice volume (and hence sea level) and deep-sea temperature are key measures of global climate change. Sea level has been documented using several independent methods over the past 0.5 million years (Myr). Older periods, however, lack such independent validation; all existing records are related to deep-sea oxygen isotope (δ(18)O) data that are influenced by processes unrelated to sea level. For deep-sea temperature, only one continuous high-resolution (Mg/Ca-based) record exists, with related sea-level estimates, spanning the past 1.5 Myr. Here we present a novel sea-level reconstruction, with associated estimates of deep-sea temperature, which independently validates the previous 0-1.5 Myr reconstruction and extends it back to 5.3 Myr ago. We find that deep-sea temperature and sea level generally decreased through time, but distinctly out of synchrony, which is remarkable given the importance of ice-albedo feedbacks on the radiative forcing of climate. In particular, we observe a large temporal offset during the onset of Plio-Pleistocene ice ages, between a marked cooling step at 2.73 Myr ago and the first major glaciation at 2.15 Myr ago. Last, we tentatively infer that ice sheets may have grown largest during glacials with more modest reductions in deep-sea temperature.

The dynamics of biogeographic ranges in the deep sea.

Science.gov (United States)

McClain, Craig R; Hardy, Sarah Mincks

2010-12-07

Anthropogenic disturbances such as fishing, mining, oil drilling, bioprospecting, warming, and acidification in the deep sea are increasing, yet generalities about deep-sea biogeography remain elusive. Owing to the lack of perceived environmental variability and geographical barriers, ranges of deep-sea species were traditionally assumed to be exceedingly large. In contrast, seamount and chemosynthetic habitats with reported high endemicity challenge the broad applicability of a single biogeographic paradigm for the deep sea. New research benefiting from higher resolution sampling, molecular methods and public databases can now more rigorously examine dispersal distances and species ranges on the vast ocean floor. Here, we explore the major outstanding questions in deep-sea biogeography. Based on current evidence, many taxa appear broadly distributed across the deep sea, a pattern replicated in both the abyssal plains and specialized environments such as hydrothermal vents. Cold waters may slow larval metabolism and development augmenting the great intrinsic ability for dispersal among many deep-sea species. Currents, environmental shifts, and topography can prove to be dispersal barriers but are often semipermeable. Evidence of historical events such as points of faunal origin and climatic fluctuations are also evident in contemporary biogeographic ranges. Continued synthetic analysis, database construction, theoretical advancement and field sampling will be required to further refine hypotheses regarding deep-sea biogeography.

Deep-sea biodiversity in the Mediterranean Sea: the known, the unknown, and the unknowable.

Directory of Open Access Journals (Sweden)

Roberto Danovaro

Full Text Available Deep-sea ecosystems represent the largest biome of the global biosphere, but knowledge of their biodiversity is still scant. The Mediterranean basin has been proposed as a hot spot of terrestrial and coastal marine biodiversity but has been supposed to be impoverished of deep-sea species richness. We summarized all available information on benthic biodiversity (Prokaryotes, Foraminifera, Meiofauna, Macrofauna, and Megafauna in different deep-sea ecosystems of the Mediterranean Sea (200 to more than 4,000 m depth, including open slopes, deep basins, canyons, cold seeps, seamounts, deep-water corals and deep-hypersaline anoxic basins and analyzed overall longitudinal and bathymetric patterns. We show that in contrast to what was expected from the sharp decrease in organic carbon fluxes and reduced faunal abundance, the deep-sea biodiversity of both the eastern and the western basins of the Mediterranean Sea is similarly high. All of the biodiversity components, except Bacteria and Archaea, displayed a decreasing pattern with increasing water depth, but to a different extent for each component. Unlike patterns observed for faunal abundance, highest negative values of the slopes of the biodiversity patterns were observed for Meiofauna, followed by Macrofauna and Megafauna. Comparison of the biodiversity associated with open slopes, deep basins, canyons, and deep-water corals showed that the deep basins were the least diverse. Rarefaction curves allowed us to estimate the expected number of species for each benthic component in different bathymetric ranges. A large fraction of exclusive species was associated with each specific habitat or ecosystem. Thus, each deep-sea ecosystem contributes significantly to overall biodiversity. From theoretical extrapolations we estimate that the overall deep-sea Mediterranean biodiversity (excluding prokaryotes reaches approximately 2805 species of which about 66% is still undiscovered. Among the biotic components

Acoustic detection of UHE neutrinos in the Mediterranean sea: status and perspective

Directory of Open Access Journals (Sweden)

Simeone Francesco

2017-01-01

Full Text Available In recent years the astro-particle community is involved in the realization of experimental apparatuses for the detection of high energy neutrinos originated in cosmic sources or produced in the interaction of Cosmic Rays with the Cosmic Microwave Background. For neutrino energies in the TeV-PeV range, optical Cherenkov detectors, that have been so far positively exploited by Baikal[1], IceCube[2] and ANTARES[3], are considered optimal. For higher energies, three different experimental techniques are under study: the detection of radio pulses produced by showers induced by a neutrino interaction, the detection of air showers initiated by neutrinos interacting with rocks or deep Earth’s atmosphere and the detection of acoustic waves produced by deposition of energy following the interaction of neutrinos in an acoustically transparent medium. The potential of the acoustic detection technique, first proposed by Askaryan[4], to build very large neutrino detectors is appealing, thanks to the optimal properties of media such as water or ice as sound propagator. Though the studies on this technique are still in an early stage, acoustic positioning systems used to locate the optical modules in underwater Cherenkov neutrino detectors, give the possibility to study the ambient noise and provide important information for the future analysis of acoustic data.

Evolutionary process of deep-sea bathymodiolus mussels.

Science.gov (United States)

Miyazaki, Jun-Ichi; de Oliveira Martins, Leonardo; Fujita, Yuko; Matsumoto, Hiroto; Fujiwara, Yoshihiro

2010-04-27

Since the discovery of deep-sea chemosynthesis-based communities, much work has been done to clarify their organismal and environmental aspects. However, major topics remain to be resolved, including when and how organisms invade and adapt to deep-sea environments; whether strategies for invasion and adaptation are shared by different taxa or unique to each taxon; how organisms extend their distribution and diversity; and how they become isolated to speciate in continuous waters. Deep-sea mussels are one of the dominant organisms in chemosynthesis-based communities, thus investigations of their origin and evolution contribute to resolving questions about life in those communities. We investigated worldwide phylogenetic relationships of deep-sea Bathymodiolus mussels and their mytilid relatives by analyzing nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I (COI) and NADH dehydrogenase subunit 4 (ND4) genes. Phylogenetic analysis of the concatenated sequence data showed that mussels of the subfamily Bathymodiolinae from vents and seeps were divided into four groups, and that mussels of the subfamily Modiolinae from sunken wood and whale carcasses assumed the outgroup position and shallow-water modioline mussels were positioned more distantly to the bathymodioline mussels. We provisionally hypothesized the evolutionary history of Bathymodilolus mussels by estimating evolutionary time under a relaxed molecular clock model. Diversification of bathymodioline mussels was initiated in the early Miocene, and subsequently diversification of the groups occurred in the early to middle Miocene. The phylogenetic relationships support the "Evolutionary stepping stone hypothesis," in which mytilid ancestors exploited sunken wood and whale carcasses in their progressive adaptation to deep-sea environments. This hypothesis is also supported by the evolutionary transition of symbiosis in that nutritional adaptation to the deep sea proceeded from extracellular

Inclusive observables and hard gluon emission in neutrino deep inelastic scattering

International Nuclear Information System (INIS)

Bouchiat, C.; Meyer, P.; Mezard, M.

1980-01-01

We derive the predictions of perturbative QCD together with non-perturbative corrections for a set of inclusive observables connected with the angular distribution of light-cone energy in deep inelastic neutrino scattering. Our particular choice of observables has been made in order to meet important physical requirements besides the necessary condition of infrared regularity. Our inclusive observables receive their dominant contribution from the quark fragmentation region. The non-perturbative contribution is calculable in a rather model-independent way and stays at an acceptable level in realistic experimental conditions. The QCD perturbative contribution, which takes the simple form of a convolution product, exhibits a strongly decreasing behaviour as a function of the Bjorken scaling variable x, superimposed on a constant background associated with the non-perturbative terms, allowing a rather clean separation of the two effects. The perturbative term being dominated by the process of hard-gluon emission, an experimental investigation of the observables discussed here may be a good way to detect the effect of gluon emission in deep inelastic neutrino scattering. (orig.)

The biomass of the deep-sea benthopelagic plankton

Science.gov (United States)

Wishner, K. F.

1980-04-01

Deep-sea benthopelagic plankton samples were collected with a specially designed opening-closing net system 10 to 100 m above the bottom in five different oceanic regions at depths from 1000 to 4700 m. Benthopelagic plankton biomasses decrease exponentially with depth. At 1000 m the biomass is about 1% that of the surface zooplankton, at 5000 m about 0.1%. Effects of differences in surface primary productivity on deep-sea plankton biomass are much less than the effect of depth and are detectable only in a few comparisons of extreme oceanic regions. The biomass at 10 m above the bottom is greater than that at 100 m above the bottom (in a three-sample comparison), which could be a consequence of an enriched near-bottom environment. The deep-sea plankton biomass in the Red Sea is anomalously low. This may be due to increased decomposition rates in the warm (22°C) deep Red Sea water, which prevent much detritus from reaching the deep sea. A model of organic carbon utilization in the benthic boundary layer (bottom 100 m), incorporating results from deep-sea sediment trap and respiration studies, indicates that the benthopelagic plankton use only a small amount of the organic carbon flux. A large fraction of the flux is unaccounted for by present estimates of benthic and benthopelagic respiration.

Challenging oil bioremediation at deep-sea hydrostatic pressure

Directory of Open Access Journals (Sweden)

Alberto Scoma

2016-08-01

Full Text Available The Deepwater Horizon (DWH accident has brought oil contamination of deep-sea environments to worldwide attention. The risk for new deep-sea spills is not expected to decrease in the future, as political pressure mounts to access deep-water fossil reserves, and poorly tested technologies are used to access oil. This also applies to the response to oil-contamination events, with bioremediation the only (biotechnology presently available to combat deep-sea spills. Many questions about the fate of petroleum-hydrocarbons at deep-sea remain unanswered, as much as the main constraints limiting bioremediation under increased hydrostatic pressures and low temperatures. The microbial pathways fueling oil take up are unclear, and the mild upregulation observed for beta-oxidation-related genes in both water and sediments contrasts with the high amount of alkanes present in the spilled-oil. The fate of solid alkanes (tar and that of hydrocarbons degradation rates was largely overlooked, as the reason why the most predominant hydrocarbonoclastic genera were not enriched at deep-sea, despite being present at hydrocarbon seeps at the Gulf of Mexico. This mini-review aims at highlighting the missing information in the field, proposing a holistic approach where in situ and ex situ studies are integrated to reveal the principal mechanisms accounting for deep-sea oil bioremediation.

Discovery Mondays - Neutrinos: journeying with the phantom particles

CERN Multimedia

2006-01-01

The target of the CNGS facility at CERN, which will enable the production of neutrinos. On 29 May, CNGS (CERN Neutrinos to Gran Sasso) will send the first neutrino beams from CERN to the Gran Sasso Laboratory in Italy. The neutrinos will journey 730 km through the earth's crust. To mark the occasion, Discovery Mondays is organising a special evening devoted to the CNGS project, whose purpose is to provide us with a better understanding of the neutrino, a particle that is still shrouded in mystery. The neutrino is an elusive particle that is very difficult to study. Masters of the art of evading capture, neutrinos can pass through thousands of kilometres of matter with little or no interaction. As you are reading this text, 400000 billion neutrinos from the sun are passing through your body every second. However, only one or two will be stopped by your body during your entire lifetime. Detecting neutrinos is therefore a very arduous task. This is why we still know so little about them. At the next Discovery ...

Positioning, alignment and absolute pointing of the ANTARES neutrino telescope

International Nuclear Information System (INIS)

Fehr, F; Distefano, C

2010-01-01

A precise detector alignment and absolute pointing is crucial for point-source searches. The ANTARES neutrino telescope utilises an array of hydrophones, tiltmeters and compasses for the relative positioning of the optical sensors. The absolute calibration is accomplished by long-baseline low-frequency triangulation of the acoustic reference devices in the deep-sea with a differential GPS system at the sea surface. The absolute pointing can be independently verified by detecting the shadow of the Moon in cosmic rays.

Deep-sea fungi

Digital Repository Service at National Institute of Oceanography (India)

Raghukumar, C; Damare, S.R.

significant in terms of carbon sequestration (5, 8). In light of this, the diversity, abundance, and role of fungi in deep-sea sediments may form an important link in the global C biogeochemistry. This review focuses on issues related to collection...

C2GT intercepting CERN neutrinos to Gran Sasso in the Gulf of Taranto to measure $\\theta_13$

CERN Document Server

Ball, A E; Camilleri, L L; Catinaccio, A; Chelkov, G A; Dydak, F; Elagin, A; Frandsen, Poul Kjaer; Gostkin, M I; Grant, A; Guskov, A; Joram, C; Krumshtein, Z; Müller, H; Postema, H; Price, M; Rovelli, T; Schinzel, D; Séguinot, Jacques; Valenti, G; Voss, R; Wotschack, J; Zhemchugov, A S

2007-01-01

Today's greatest challenge in accelerator-based neutrino physics is to measure the mixing angle \\thonethree\\ which is known to be much smaller than the solar mixing angle \\thonetwo\\ and the atmospheric mixing angle \\thtwothree . A non-zero value of the angle \\thonethree\\ is a prerequisite for observing CP violation in neutrino mixing. In this paper, we discuss a deep-sea neutrino experiment with 1.5~Mt fiducial target mass in the Gulf of Taranto with the prime objective of measuring \\thonethree. The detector is exposed to the CERN neutrino beam to Gran Sasso in off-axis geometry. Monochromatic muon-neutrinos of $\\approx 800$~MeV energy are the dominant beam component. Neutrinos are detected through quasi-elastic, charged-current reactions in sea water; electrons and muons are detected in a large-surface, ring-imaging Cherenkov detector. The profile of the seabed in the Gulf of Taranto allows for a moveable experiment at variable distances from CERN, starting at 1100 km. From the oscillatory pattern of the dis...

Lessons learned from the NEPTUNE power system, and other deep-sea adventures

International Nuclear Information System (INIS)

Kirkham, Harold

2006-01-01

The development of underwater science systems presents some challenging technical issues. It seems that the best efforts of the engineers and scientists involved are sometimes inadequate, and projects that once seemed straightforward end up being late or over-budget, or cancelled. This paper will review some of the lessons that may be learned from the examples of three science projects in the deep ocean: the Deep Underwater Muon and Neutrino Detector neutrino detector, the H 2 O observatory, and the power system part of the NEPTUNE regional cabled observatory

Ploughing the deep sea floor.

Science.gov (United States)

Puig, Pere; Canals, Miquel; Company, Joan B; Martín, Jacobo; Amblas, David; Lastras, Galderic; Palanques, Albert

2012-09-13

Bottom trawling is a non-selective commercial fishing technique whereby heavy nets and gear are pulled along the sea floor. The direct impact of this technique on fish populations and benthic communities has received much attention, but trawling can also modify the physical properties of seafloor sediments, water–sediment chemical exchanges and sediment fluxes. Most of the studies addressing the physical disturbances of trawl gear on the seabed have been undertaken in coastal and shelf environments, however, where the capacity of trawling to modify the seafloor morphology coexists with high-energy natural processes driving sediment erosion, transport and deposition. Here we show that on upper continental slopes, the reworking of the deep sea floor by trawling gradually modifies the shape of the submarine landscape over large spatial scales. We found that trawling-induced sediment displacement and removal from fishing grounds causes the morphology of the deep sea floor to become smoother over time, reducing its original complexity as shown by high-resolution seafloor relief maps. Our results suggest that in recent decades, following the industrialization of fishing fleets, bottom trawling has become an important driver of deep seascape evolution. Given the global dimension of this type of fishery, we anticipate that the morphology of the upper continental slope in many parts of the world’s oceans could be altered by intensive bottom trawling, producing comparable effects on the deep sea floor to those generated by agricultural ploughing on land.

Evolutionary process of deep-sea bathymodiolus mussels.

Directory of Open Access Journals (Sweden)

Jun-Ichi Miyazaki

Full Text Available BACKGROUND: Since the discovery of deep-sea chemosynthesis-based communities, much work has been done to clarify their organismal and environmental aspects. However, major topics remain to be resolved, including when and how organisms invade and adapt to deep-sea environments; whether strategies for invasion and adaptation are shared by different taxa or unique to each taxon; how organisms extend their distribution and diversity; and how they become isolated to speciate in continuous waters. Deep-sea mussels are one of the dominant organisms in chemosynthesis-based communities, thus investigations of their origin and evolution contribute to resolving questions about life in those communities. METHODOLOGY/PRINCIPAL FINDING: We investigated worldwide phylogenetic relationships of deep-sea Bathymodiolus mussels and their mytilid relatives by analyzing nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I (COI and NADH dehydrogenase subunit 4 (ND4 genes. Phylogenetic analysis of the concatenated sequence data showed that mussels of the subfamily Bathymodiolinae from vents and seeps were divided into four groups, and that mussels of the subfamily Modiolinae from sunken wood and whale carcasses assumed the outgroup position and shallow-water modioline mussels were positioned more distantly to the bathymodioline mussels. We provisionally hypothesized the evolutionary history of Bathymodilolus mussels by estimating evolutionary time under a relaxed molecular clock model. Diversification of bathymodioline mussels was initiated in the early Miocene, and subsequently diversification of the groups occurred in the early to middle Miocene. CONCLUSIONS/SIGNIFICANCE: The phylogenetic relationships support the "Evolutionary stepping stone hypothesis," in which mytilid ancestors exploited sunken wood and whale carcasses in their progressive adaptation to deep-sea environments. This hypothesis is also supported by the evolutionary transition of

The physics of relic neutrinos

International Nuclear Information System (INIS)

Dighe, A.; Pastor, S.; Smirnov, A.

1998-12-01

We report on the main results presented at the workshop on the Physics of Relic Neutrinos. The study of relic neutrinos involves a broad spectrum of problems in particle physics, astrophysics and cosmology. Features of baryogenesis and leptogenesis could be imprinted in the properties of the relic neutrino sea. Relic neutrinos played a crucial role in the big bang nucleosynthesis. Being the hot component of the dark matter, they have participated in the structure formation in the universe. Although the direct detection of the sea seems impossible at this stage, there could be various indirect manifestations of these neutrinos which would allow us to study the properties of the sea both in the past and at the present epoch. (author)

Bathymetric and geographic population structure in the pan-Atlantic deep-sea bivalve Deminucula atacellana (Schenck, 1939).

Science.gov (United States)

Zardus, John D; Etter, Ron J; Chase, Michael R; Rex, Michael A; Boyle, Elizabeth E

2006-03-01

The deep-sea soft-sediment environment hosts a diverse and highly endemic fauna of uncertain origin. We know little about how this fauna evolved because geographic patterns of genetic variation, the essential information for inferring patterns of population differentiation and speciation are poorly understood. Using formalin-fixed specimens from archival collections, we quantify patterns of genetic variation in the protobranch bivalve Deminucula atacellana, a species widespread throughout the Atlantic Ocean at bathyal and abyssal depths. Samples were taken from 18 localities in the North American, West European and Argentine basins. A hypervariable region of mitochondrial 16S rDNA was amplified by polymerase chain reaction (PCR) and sequenced from 130 individuals revealing 21 haplotypes. Except for several important exceptions, haplotypes are unique to each basin. Overall gene diversity is high (h = 0.73) with pronounced population structure (Phi(ST) = 0.877) and highly significant geographic associations (P < 0.0001). Sequences cluster into four major clades corresponding to differences in geography and depth. Genetic divergence was much greater among populations at different depths within the same basin, than among those at similar depths but separated by thousands of kilometres. Isolation by distance probably explains much of the interbasin variation. Depth-related divergence may reflect historical patterns of colonization or strong environmental selective gradients. Broadly distributed deep-sea organisms can possess highly genetically divergent populations, despite the lack of any morphological divergence.

Progress toward a Km-scale neutrino detector in the deep ocean

International Nuclear Information System (INIS)

Stokstad, R.G.

1997-11-01

The best particles for observing distant objects are photons and neutrinos. Because of the neutrino's weak interaction cross section, detectors suitable for astronomy must be very large and well shielded from cosmic rays. Eventually, a detector with the order of a square km of effective area will be needed for systematic observations of distant point sources such as active galactic nuclei. Prototype detectors are currently being developed at several sites in the ocean, at Lake Baikal, and in Antarctica. This talk summarizes the status of the projects that use the deep ocean for the detector medium and shielding: DUMAND, NESTOR and ANTARES. Technical developments will be needed for a future km-scale detector; progress on one of these, a digital electronic system, is also described

On the radiative corrections to the neutrino deep inelastic scattering

International Nuclear Information System (INIS)

Bardin, D.Yu.; Dokuchaeva, V.A.

1986-01-01

A unique set of formulae is presented for the radiative corrections to the double differential cross section of deep inelastic neutrino scattering in channels of charged and neutral currents within a simple quark parton model in a renormalization scheme on mass-shell. It is shown that these cross sections when being integrated up to the one-dimensional distribution or up to the total cross section reproduce many results existing in the literature

Biodiversity loss from deep-sea mining

OpenAIRE

C. L. Van Dover; J. A. Ardron; E. Escobar; M. Gianni; K. M. Gjerde; A. Jaeckel; D. O. B. Jones; L. A. Levin; H. Niner; L. Pendleton; C. R. Smith; T. Thiele; P. J. Turner; L. Watling; P. P. E. Weaver

2017-01-01

The emerging deep-sea mining industry is seen by some to be an engine for economic development in the maritime sector. The International Seabed Authority (ISA) – the body that regulates mining activities on the seabed beyond national jurisdiction – must also protect the marine environment from harmful effects that arise from mining. The ISA is currently drafting a regulatory framework for deep-sea mining that includes measures for environmental protection. Responsible mining increasingly stri...

Stable isotope geochemistry of deep sea cherts

Energy Technology Data Exchange (ETDEWEB)

Kolodny, Y; Epstein, S [California Inst. of Tech., Pasadena (USA). Div. of Geological Sciences

1976-10-01

Seventy four samples of DSDP (Deep Sea Drilling Project) recovered cherts of Jurassic to Miocene age from varying locations, and 27 samples of on-land exposed cherts were analyzed for the isotopic composition of their oxygen and hydrogen. These studies were accompanied by mineralogical analyses and some isotopic analyses of the coexisting carbonates. delta/sup 18/0 of chert ranges between 27 and 39 parts per thousand relative to SMOW, delta/sup 18/0 of porcellanite - between 30 and 42 parts per thousand. The consistent enrichment of opal-CT in porcellanites in /sup 18/0 with respect to coexisting microcrystalline quartz in chert is probably a reflection of a different temperature (depth) of diagenesis of the two phases. delta/sup 18/0 of deep sea cherts generally decrease with increasing age, indicating an overall cooling of the ocean bottom during the last 150 m.y. A comparison of this trend with that recorded by benthonic foraminifera (Douglas et al., Initial Reports of the Deep Sea Drilling Project; 32:509(1975)) indicates the possibility of delta/sup 18/0 in deep sea cherts not being frozen in until several tens of millions of years after deposition. Cherts of any Age show a spread of delta/sup 18/0 values, increasing diagenesis being reflected in a lowering of delta/sup 18/0. Drusy quartz has the lowest delta/sup 18/0 values. On land exposed cherts are consistently depleted in /sup 18/0 in comparison to their deep sea time equivalent cherts. Water extracted from deep sea cherts ranges between 0.5 and 1.4 wt%. deltaD of this water ranges between -78 and -95 parts per thousand and is not a function of delta/sup 18/0 of the cherts (or the temperature of their formation).

Massive Cherenkov neutrino facilities?their evolution, their future: Twenty-five years at these International Neutrino Conferences

International Nuclear Information System (INIS)

Sulak, Lawrence R.

2005-01-01

This review traces the evolution of massive water Cherenkov tracking calorimeters. Pioneering concepts, first presented in this conference a quarter of a century ago, have led to 1) IMB, the first large detector (10kT), which was designed primarily to search for proton decay, and secondarily to be sensitive to supernova neutrinos and atmospheric oscillations, and 2) Dumand, an attempt to initiate the search for TeV astrophysical neutrinos with a prototype for a 1 km 3 telescope. The concepts and initial work on IMB influenced subsequent detectors: Kamiokande, Super-K, SNO, and, in part, Kamland. These detectors have to their credit the elucidation of the physics of atmospheric, solar, reactor and supernova neutrinos. With the advent of the K2K beam, controlled accelerator neutrinos confirm the atmospheric studies. The path breaking developments of Dumand now are incorporated in the high-volume Amanda and Antares detectors, as well as their sequels, IceCube and the proposed Cubic Kilometer detector. The future (ultimate?) facilities have new physics challenges: A high-resolution megaton detector, eventually coupled with an intense accelerator neutrino source, is critical for precision studies of neutrino oscillation parameters and for the potential discovery of CP violation in the lepton sector. The Gigaton TeV neutrino telescopes (IceCube and Cubic Kilometer) seek to open high-energy neutrino astronomy, still an elusive goal. (Amanda, IceCube, and UNO, as well as Minos, Icarus and other large neutrino facilities using non-Cherenkov technologies, are treated in other contributions to this volume.)

Vision in the deep sea.

Science.gov (United States)

Warrant, Eric J; Locket, N Adam

2004-08-01

The deep sea is the largest habitat on earth. Its three great faunal environments--the twilight mesopelagic zone, the dark bathypelagic zone and the vast flat expanses of the benthic habitat--are home to a rich fauna of vertebrates and invertebrates. In the mesopelagic zone (150-1000 m), the down-welling daylight creates an extended scene that becomes increasingly dimmer and bluer with depth. The available daylight also originates increasingly from vertically above, and bioluminescent point-source flashes, well contrasted against the dim background daylight, become increasingly visible. In the bathypelagic zone below 1000 m no daylight remains, and the scene becomes entirely dominated by point-like bioluminescence. This changing nature of visual scenes with depth--from extended source to point source--has had a profound effect on the designs of deep-sea eyes, both optically and neurally, a fact that until recently was not fully appreciated. Recent measurements of the sensitivity and spatial resolution of deep-sea eyes--particularly from the camera eyes of fishes and cephalopods and the compound eyes of crustaceans--reveal that ocular designs are well matched to the nature of the visual scene at any given depth. This match between eye design and visual scene is the subject of this review. The greatest variation in eye design is found in the mesopelagic zone, where dim down-welling daylight and bio-luminescent point sources may be visible simultaneously. Some mesopelagic eyes rely on spatial and temporal summation to increase sensitivity to a dim extended scene, while others sacrifice this sensitivity to localise pinpoints of bright bioluminescence. Yet other eyes have retinal regions separately specialised for each type of light. In the bathypelagic zone, eyes generally get smaller and therefore less sensitive to point sources with increasing depth. In fishes, this insensitivity, combined with surprisingly high spatial resolution, is very well adapted to the

Age-dependent mixing of deep-sea sediments

International Nuclear Information System (INIS)

Smith, C.R.; Maggaard, L.; Pope, R.H.; DeMaster, D.J.

1993-01-01

Rates of bioturbation measured in deep-sea sediments commonly are tracer dependent; in particular, shorter lived radiotracers (such as 234 Th) often yield markedly higher diffusive mixing coefficients than their longer-lived counterparts (e.g., 210 Pb). At a single station in the 1,240-m deep Santa Catalina Basin, the authors document a strong negative correlation between bioturbation rate and tracer half-life. Sediment profiles of 234 Th (half-life = 24 days) yield an average mixing coefficient (60 cm 2 y -1 ) two orders of magnitude greater than that for 210 Pb (half-life = 22 y, mean mixing coefficient = 0.4 cm 2 y -1 ). A similar negative relationship between mixing rate and tracer time scale is observed at thirteen other deep-sea sites in which multiple radiotracers have been used to assess diffusive mixing rates. This relationship holds across a variety of radiotracer types and time scales. The authors hypothesize that this negative relationship results from age-dependent mixing, a process in which recently sedimented, food-rich particles are ingested and mixed at higher rates by deposit feeders than are older, food-poor particles. Results from an age-dependent mixing model demonstrate that this process indeed can yield the bioturbation-rate vs. tracer-time-scale correlations observed in deep-sea sediments. Field data on mixing rates of recently sedimented particles, as well as the radiotracer activity of deep-sea deposit feeders, provide strong support for the age-dependent mixing model. The presence of age-dependent mixing in deep-sea sediments may have major implications for diagenetic modeling, requiring a match between the characteristic time scales of mixing tracers and modeled reactants. 102 refs., 6 figs., 5 tabs

Measurement of the nucleon structure function in the deep inelastic neutrino-iron scattering with a wide-band neutrino beam

International Nuclear Information System (INIS)

Flottmann, T.

1982-01-01

In this thesis the nucleon structure function xF 3 is determined from the inclusive measurement of the deep inelastic neutrino nucleon charged current interaction. The data were taken in the CERN wide band neutrino beam using the detector of the CERN-Dortmund-Heidelberg-Saclay collaboration. This detector serves at the same time as target, as hadron energy calorimeter and as muon spectrometer. One major aspect of this work was to study the possibility of using high statistics wide band beam data for structure function analysis. The systematic errors specific to this kind of beam are investigated. To obtain the differential cross sections about 100000 neutrino and 75000 antineutrino events in the energy range 20-200 GeV are analysed. The differential cross sections are normalized to the total cross sections, as measured in the narrow band beam by the same collaboration. The calculated structure function xF 3 shows significant deviations from scaling. These scaling violations are compared quantitatively with the predictions of quantum chromodynamics. (orig.) [de

Transcriptomes and expression profiling of deep-sea corals from the Red Sea provide insight into the biology of azooxanthellate corals.

Science.gov (United States)

Yum, Lauren K; Baumgarten, Sebastian; Röthig, Till; Roder, Cornelia; Roik, Anna; Michell, Craig; Voolstra, Christian R

2017-07-25

Despite the importance of deep-sea corals, our current understanding of their ecology and evolution is limited due to difficulties in sampling and studying deep-sea environments. Moreover, a recent re-evaluation of habitat limitations has been suggested after characterization of deep-sea corals in the Red Sea, where they live at temperatures of above 20 °C at low oxygen concentrations. To gain further insight into the biology of deep-sea corals, we produced reference transcriptomes and studied gene expression of three deep-sea coral species from the Red Sea, i.e. Dendrophyllia sp., Eguchipsammia fistula, and Rhizotrochus typus. Our analyses suggest that deep-sea coral employ mitochondrial hypometabolism and anaerobic glycolysis to manage low oxygen conditions present in the Red Sea. Notably, we found expression of genes related to surface cilia motion that presumably enhance small particle transport rates in the oligotrophic deep-sea environment. This is the first study to characterize transcriptomes and in situ gene expression for deep-sea corals. Our work offers several mechanisms by which deep-sea corals might cope with the distinct environmental conditions present in the Red Sea As such, our data provide direction for future research and further insight to organismal response of deep-sea coral to environmental change and ocean warming.

Transcriptomes and expression profiling of deep-sea corals from the Red Sea provide insight into the biology of azooxanthellate corals

KAUST Repository

Yum, Lauren

2017-07-19

Despite the importance of deep-sea corals, our current understanding of their ecology and evolution is limited due to difficulties in sampling and studying deep-sea environments. Moreover, a recent re-evaluation of habitat limitations has been suggested after characterization of deep-sea corals in the Red Sea, where they live at temperatures of above 20 °C at low oxygen concentrations. To gain further insight into the biology of deep-sea corals, we produced reference transcriptomes and studied gene expression of three deep-sea coral species from the Red Sea, i.e. Dendrophyllia sp., Eguchipsammia fistula, and Rhizotrochus typus. Our analyses suggest that deep-sea coral employ mitochondrial hypometabolism and anaerobic glycolysis to manage low oxygen conditions present in the Red Sea. Notably, we found expression of genes related to surface cilia motion that presumably enhance small particle transport rates in the oligotrophic deep-sea environment. This is the first study to characterize transcriptomes and in situ gene expression for deep-sea corals. Our work offers several mechanisms by which deep-sea corals might cope with the distinct environmental conditions present in the Red Sea As such, our data provide direction for future research and further insight to organismal response of deep-sea coral to environmental change and ocean warming.

Transcriptomes and expression profiling of deep-sea corals from the Red Sea provide insight into the biology of azooxanthellate corals

KAUST Repository

Yum, Lauren; Baumgarten, Sebastian; Rö thig, Till; Roder, Cornelia; Roik, Anna Krystyna; Michell, Craig; Voolstra, Christian R.

2017-01-01

Despite the importance of deep-sea corals, our current understanding of their ecology and evolution is limited due to difficulties in sampling and studying deep-sea environments. Moreover, a recent re-evaluation of habitat limitations has been suggested after characterization of deep-sea corals in the Red Sea, where they live at temperatures of above 20 °C at low oxygen concentrations. To gain further insight into the biology of deep-sea corals, we produced reference transcriptomes and studied gene expression of three deep-sea coral species from the Red Sea, i.e. Dendrophyllia sp., Eguchipsammia fistula, and Rhizotrochus typus. Our analyses suggest that deep-sea coral employ mitochondrial hypometabolism and anaerobic glycolysis to manage low oxygen conditions present in the Red Sea. Notably, we found expression of genes related to surface cilia motion that presumably enhance small particle transport rates in the oligotrophic deep-sea environment. This is the first study to characterize transcriptomes and in situ gene expression for deep-sea corals. Our work offers several mechanisms by which deep-sea corals might cope with the distinct environmental conditions present in the Red Sea As such, our data provide direction for future research and further insight to organismal response of deep-sea coral to environmental change and ocean warming.

Time calibration with atmospheric muon tracks in the ANTARES neutrino telescope

CERN Document Server

Adrián-Martínez, S.; André, M.; Anton, G.; Ardid, M.; Aubert, J.-J.; Baret, B.; Barrios-Martí, J.; Basa, S.; Bertin, V.; Biagi, S.; Bogazzi, C.; Bormuth, R.; Bou-Cabo, M.; Bouwhuis, M.C.; Bruijn, R.; Brunner, J.; Busto, J.; Capone, A.; Caramete, L.; Carr, J.; Chiarusi, T.; Circella, M.; Coniglione, R.; Costantini, H.; Coyle, P.; Creusot, A.; Dekeyser, I.; Deschamps, A.; De Bonis, G.; Distefano, C.; Donzaud, C.; Dornic, D.; Drouhin, D.; Dumas, A.; Eberl, T.; Elsässer, D.; Enzenhöfer, A.; Fehn, K.; Felis, I.; Fermani, P.; Flaminio, V.; Folger, F.; Fusco, L.A.; Galatà, S.; Gay, P.; Geißelsöder, S.; Geyer, K.; Giordano, V.; Gleixner, A.; Gracia-Ruiz, R.; Gómez-González, J.P.; Graf, K.; van Haren, H.; Heijboer, A.J.; Hello, Y.; Hernández-Rey, J.J.; Herrero, A.; Hößl, J.; Hofestädt, J.; Hugon, C.; James, C.W.; de Jong, M.; Kadler, M.; Kalekin, O.; Katz, U.; Kießling, D.; Kooijman, P.; Kouchner, A.; Kreykenbohm, I.; Kulikovskiy, V.; Lahmann, R.; Lambard, G.; Lattuada, D.; Lefèvre, D.; Leonora, E.; Loucatos, S.; Mangano, S.; Marcelin, M.; Margiotta, A.; Marinelli, A.; Martínez-Mora, J.A.; Martini, S.; Mathieu, A.; Michael, T.; Migliozzi, P.; Moussa, A.; Mueller, C.; Neff, M.; Nezri, E.; Păvălaş, G.E.; Pellegrino, C.; Perrina, C.; Piattelli, P.; Popa, V.; Pradier, T.; Racca, C.; Riccobene, G.; Richter, R.; Roensch, K.; Rostovtsev, A.; Saldaña, M.; Samtleben, D.F.E.; Sánchez-Losa, A.; Sanguineti, M.; Sapienza, P.; Schmid, J.; Schnabel, J.; Schulte, S.; Schüssler, F.; Seitz, T.; Sieger, C.; Spurio, M.; Steijger, J.J.M.; Stolarczyk, Th.; Taiuti, M.; Tamburini, C.; Trovato, A.; Tselengidou, M.; Tönnis, C.; Turpin, D.; Vallage, B.; Vallée, C.; Van Elewyck, V.; Visser, E.; Vivolo, D.; Wagner, S.; Wilms, J.; Zornoza, J.D.; Zúñiga, J.

The ANTARES experiment consists of an array of photomultipliers distributed along 12 lines and located deep underwater in the Mediterranean Sea. It searches for astrophysical neutrinos collecting the Cherenkov light induced by the charged particles, mainly muons, produced in neutrino interactions around the detector. Since at energies of $\\sim$10 TeV the muon and the incident neutrino are almost collinear, it is possible to use the ANTARES detector as a neutrino telescope and identify a source of neutrinos in the sky starting from a precise reconstruction of the muon trajectory. To get this result, the arrival times of the Cherenkov photons must be accurately measured. A to perform time calibrations with the precision required to have optimal performances of the instrument is described. The reconstructed tracks of the atmospheric muons in the ANTARES detector are used to determine the relative time offsets between photomultipliers. Currently, this method is used to obtain the time calibration constants for ph...

Zooplankton at deep Red Sea brine pools

KAUST Repository

Kaartvedt, Stein

2016-03-02

The deep-sea anoxic brines of the Red Sea comprise unique, complex and extreme habitats. These environments are too harsh for metazoans, while the brine–seawater interface harbors dense microbial populations. We investigated the adjacent pelagic fauna at two brine pools using net tows, video records from a remotely operated vehicle and submerged echosounders. Waters just above the brine pool of Atlantis II Deep (2000 m depth) appeared depleted of macrofauna. In contrast, the fauna appeared to be enriched at the Kebrit Deep brine–seawater interface (1466 m).

Can the new Neutrino Telescopes and LHC reveal the gravitational proprieties of antimatter?

CERN Document Server

Hajdukovic, Dragan Slavkov

2011-01-01

What are the gravitational proprieties of antimatter is still not known. One possibility is the gravitational repulsion between matter and antimatter (in short we call it antigravity). We point out two possible signatures of the assumed existence of antigravity. First, the supermassive black hole in the center of our Galaxy (Southern Sky)and in the center of the Andromeda Galaxy (Northern Sky)may produce a flux of antineutrinos measurable with the new generation of the neutrino telescopes; like the IceCube Neutrino Detector under construction at the South Pole, and the future one cubic kilometer telescope in Mediterranean Sea. Second, if microscopic black holes are successfully produced at the Large Hadron Collider (LHC) at CERN, their thermal (Hawking's) radiation should be dominated by a non-thermal radiation caused by antigravity.

Genetic diversity of archaea in deep-sea hydrothermal vent environments.

Science.gov (United States)

Takai, K; Horikoshi, K

1999-08-01

Molecular phylogenetic analysis of naturally occurring archaeal communities in deep-sea hydrothermal vent environments was carried out by PCR-mediated small subunit rRNA gene (SSU rDNA) sequencing. As determined through partial sequencing of rDNA clones amplified with archaea-specific primers, the archaeal populations in deep-sea hydrothermal vent environments showed a great genetic diversity, and most members of these populations appeared to be uncultivated and unidentified organisms. In the phylogenetic analysis, a number of rDNA sequences obtained from deep-sea hydrothermal vents were placed in deep lineages of the crenarchaeotic phylum prior to the divergence of cultivated thermophilic members of the crenarchaeota or between thermophilic members of the euryarchaeota and members of the methanogen-halophile clade. Whole cell in situ hybridization analysis suggested that some microorganisms of novel phylotypes predicted by molecular phylogenetic analysis were likely present in deep-sea hydrothermal vent environments. These findings expand our view of the genetic diversity of archaea in deep-sea hydrothermal vent environments and of the phylogenetic organization of archaea.

Diverse deep-sea fungi from the South China Sea and their antimicrobial activity.

Science.gov (United States)

Zhang, Xiao-Yong; Zhang, Yun; Xu, Xin-Ya; Qi, Shu-Hua

2013-11-01

We investigated the diversity of fungal communities in nine different deep-sea sediment samples of the South China Sea by culture-dependent methods followed by analysis of fungal internal transcribed spacer (ITS) sequences. Although 14 out of 27 identified species were reported in a previous study, 13 species were isolated from sediments of deep-sea environments for the first report. Moreover, these ITS sequences of six isolates shared 84-92 % similarity with their closest matches in GenBank, which suggested that they might be novel phylotypes of genera Ajellomyces, Podosordaria, Torula, and Xylaria. The antimicrobial activities of these fungal isolates were explored using a double-layer technique. A relatively high proportion (56 %) of fungal isolates exhibited antimicrobial activity against at least one pathogenic bacterium or fungus among four marine pathogenic microbes (Micrococcus luteus, Pseudoaltermonas piscida, Aspergerillus versicolor, and A. sydowii). Out of these antimicrobial fungi, the genera Arthrinium, Aspergillus, and Penicillium exhibited antibacterial and antifungal activities, while genus Aureobasidium displayed only antibacterial activity, and genera Acremonium, Cladosporium, Geomyces, and Phaeosphaeriopsis displayed only antifungal activity. To our knowledge, this is the first report to investigate the diversity and antimicrobial activity of culturable deep-sea-derived fungi in the South China Sea. These results suggest that diverse deep-sea fungi from the South China Sea are a potential source for antibiotics' discovery and further increase the pool of fungi available for natural bioactive product screening.

Deep-sea ciliates: Recorded diversity and experimental studies on pressure tolerance

Science.gov (United States)

Schoenle, Alexandra; Nitsche, Frank; Werner, Jennifer; Arndt, Hartmut

2017-10-01

Microbial eukaryotes play an important role in biogeochemical cycles not only in productive surface waters but also in the deep sea. Recent studies based on metagenomics report deep-sea protistan assemblages totally different from continental slopes and shelf waters. To give an overview about the ciliate fauna recorded from the deep sea we summarized the available information on ciliate occurrence in the deep sea. Our literature review revealed that representatives of the major phylogenetic groups of ciliates were recorded from the deep sea (> 1000 m depth): Karyorelictea, Heterotrichea, Spirotrichea (Protohypotrichia, Euplotia, Oligotrichia, Choreotrichia, Hypotrichia), Armophorea (Armophorida), Litostomatea (Haptoria), Conthreep (Phyllopharyngea incl. Cyrtophoria, Chonotrichia, Suctoria; Nassophorea incl. Microthoracida, Synhymeniida, Nassulida; Colpodea incl. Bursariomorphida, Cyrtolophosidida; Prostomatea; Plagiopylea incl. Plagiopylida, Odontostomatida; Oligohymenophorea incl. Peniculia, Scuticociliatia, Hymenostomatia, Apostomatia, Peritrichia, Astomatia). Species occurring in both habitats, deep sea and shallow water, are rarely found to our knowledge to date. This indicates a high deep-sea specific ciliate fauna. Our own studies of similar genotypes (SSU rDNA and cox1 gene) revealed that two small scuticociliate species (Pseudocohnilembus persalinus and Uronema sp.) could be isolated from surface as well as deep waters (2687 m, 5276 m, 5719 m) of the Pacific. The adaptation to deep-sea conditions was investigated by exposing the ciliate isolates directly or stepwise to different hydrostatic pressures ranging from 1 to 550 atm at temperatures of 2 °C and 13 °C. Although the results indicated no general barophilic behavior, all four isolated strains survived the highest established pressure. A better survival at 550 atm could be observed for the lower temperature. Among microbial eukaryotes, ciliates should be considered as a diverse and potentially

Species distribution models of tropical deep-sea snappers.

Directory of Open Access Journals (Sweden)

Céline Gomez

Full Text Available Deep-sea fisheries provide an important source of protein to Pacific Island countries and territories that are highly dependent on fish for food security. However, spatial management of these deep-sea habitats is hindered by insufficient data. We developed species distribution models using spatially limited presence data for the main harvested species in the Western Central Pacific Ocean. We used bathymetric and water temperature data to develop presence-only species distribution models for the commercially exploited deep-sea snappers Etelis Cuvier 1828, Pristipomoides Valenciennes 1830, and Aphareus Cuvier 1830. We evaluated the performance of four different algorithms (CTA, GLM, MARS, and MAXENT within the BIOMOD framework to obtain an ensemble of predicted distributions. We projected these predictions across the Western Central Pacific Ocean to produce maps of potential deep-sea snapper distributions in 32 countries and territories. Depth was consistently the best predictor of presence for all species groups across all models. Bathymetric slope was consistently the poorest predictor. Temperature at depth was a good predictor of presence for GLM only. Model precision was highest for MAXENT and CTA. There were strong regional patterns in predicted distribution of suitable habitat, with the largest areas of suitable habitat (> 35% of the Exclusive Economic Zone predicted in seven South Pacific countries and territories (Fiji, Matthew & Hunter, Nauru, New Caledonia, Tonga, Vanuatu and Wallis & Futuna. Predicted habitat also varied among species, with the proportion of predicted habitat highest for Aphareus and lowest for Etelis. Despite data paucity, the relationship between deep-sea snapper presence and their environments was sufficiently strong to predict their distribution across a large area of the Pacific Ocean. Our results therefore provide a strong baseline for designing monitoring programs that balance resource exploitation and

Radio-active waste disposal and deep-sea biology

International Nuclear Information System (INIS)

Rice, A.L.

1978-01-01

The deep-sea has been widely thought of as a remote, sparsely populated, and biologically inactive environment, well suited to receive the noxious products of nuclear fission processes. Much of what is known of abyssal biology tends to support this view, but there are a few disquieting contra-indications. The realisation, in recent years, that many animal groups show a previously unsuspected high species diversity in the deep-sea emphasized the paucity of our knowledge of this environment. More dramatically, the discovery of a large, active, and highly mobile abysso-bentho-pelagic fauna changed the whole concept of abyssal life. Finally, while there is little evidence for the existence of vertical migration patterns linking the deep-sea bottom communities with those of the overlying water layers, there are similarly too few negative results for the possibility of such transport mechanisms to be dismissed. In summary, biological knowledge of the abyss is insufficient to answer the questions raised in connection with deep-sea dumping, but in the absence of adequate answers it might be dangerous to ignore the questions

A Deep-Sea Simulation.

Science.gov (United States)

Montes, Georgia E.

1997-01-01

Describes an activity that simulates exploration techniques used in deep-sea explorations and teaches students how this technology can be used to take a closer look inside volcanoes, inspect hazardous waste sites such as nuclear reactors, and explore other environments dangerous to humans. (DDR)

Indian deep-sea environment experiment (INDEX): Monitoring the restoration of marine enviroment after artificial disturbance to simulate deep-sea mining in central Indian Basin

Digital Repository Service at National Institute of Oceanography (India)

Sharma, R.

the restoration of marine environment after artificial disturbance to simulate deep-sea mining in Central Indian Basin Guest Editor Rahul Sharma Note from guest editor A special issue on Indian Deep-sea Environment Experiment (INDEX) conducted by the scientists... in Geochemical Associations in Artificially Disturbed Deep-Sea Sediments B. Nagender Nath, G. Parthiban, S. Banaulikar, and Subhadeep Sarkar Marine Georesources and Geotechnology, 24:61–62, 2006 Copyright # Taylor & Francis Group, LLC ISSN: 1064-119X print/1521...

A Modeling Study of Deep Water Renewal in the Red Sea

Science.gov (United States)

Yao, F.; Hoteit, I.

2016-02-01

Deep water renewal processes in the Red Sea are examined in this study using a 50-year numerical simulation from 1952-2001. The deep water in the Red Sea below the thermocline ( 200 m) exhibits a near-uniform vertical structure in temperature and salinity, but geochemical tracer distributions, such as 14C and 3He, and dissolved oxygen concentrations indicate that the deep water is renewed on time scales as short as 36 years. The renewal process is accomplished through a deep overturning cell that consists of a southward bottom current and a northward returning current at depths of 400-600 m. Three sources regions are proposed for the formation of the deep water, including two deep outflows from the Gulfs of Aqaba and Suez and winter deep convections in the northern Red Sea. The MITgcm (MIT general circulation model), which has been used to simulate the shallow overturning circulations in the Red Sea, is configured in this study with increased resolutions in the deep water. During the 50 years of simulation, artificial passive tracers added in the model indicate that the deep water in the Red Sea was only episodically renewed during some anomalously cold years; two significant episodes of deep water renewal are reproduced in the winters of 1983 and 1992, in accordance with reported historical hydrographic observations. During these renewal events, deep convections reaching the bottom of the basin occurred, which further facilitated deep sinking of the outflows from the Gulfs of Aqaba and Suez. Ensuing spreading of the newly formed deep water along the bottom caused upward displacements of thermocline, which may have profound effects on the water exchanges in the Strait of Bab el Mandeb between the Red Sea and the Gulf of Aden and the functioning of the ecosystem in the Red Sea by changing the vertical distributions of nutrients.

Observations of Deep-Sea Coral and Sponge Occurrences from the NOAA National Deep-Sea Coral and Sponge Database, 1842-Present (NCEI Accession 0145037)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NOAA’s Deep-Sea Coral Research and Technology Program (DSC-RTP) compiles a national database of the known locations of deep-sea corals and sponges in U.S....

Assessing Deep Sea Communities Through Seabed Imagery

Science.gov (United States)

Matkin, A. G.; Cross, K.; Milititsky, M.

2016-02-01

The deep sea still remains virtually unexplored. Human activity, such as oil and gas exploration and deep sea mining, is expanding further into the deep sea, increasing the need to survey and map extensive areas of this habitat in order to assess ecosystem health and value. The technology needed to explore this remote environment has been advancing. Seabed imagery can cover extensive areas of the seafloor and investigate areas where sampling with traditional coring methodologies is just not possible (e.g. cold water coral reefs). Remotely operated vehicles (ROVs) are an expensive option, so drop or towed camera systems can provide a more viable and affordable alternative, while still allowing for real-time control. Assessment of seabed imagery in terms of presence, abundance and density of particular species can be conducted by bringing together a variety of analytical tools for a holistic approach. Sixteen deep sea transects located offshore West Africa were investigated with a towed digital video telemetry system (DTS). Both digital stills and video footage were acquired. An extensive data set was obtained from over 13,000 usable photographs, allowing for characterisation of the different habitats present in terms of community composition and abundance. All observed fauna were identified to the lowest taxonomic level and enumerated when possible, with densities derived after the seabed area was calculated for each suitable photograph. This methodology allowed for consistent assessment of the different habitat types present, overcoming constraints, such as specific taxa that cannot be enumerated, such as sponges, corals or bryozoans, the presence of mobile and sessile species, or the level of taxonomic detail. Although this methodology will not enable a full characterisation of a deep sea community, in terms of species composition for instance, itt will allow a robust assessment of large areas of the deep sea in terms of sensitive habitats present and community

Deep sea radionuclides

International Nuclear Information System (INIS)

Kanisch, G.; Vobach, M.

1993-01-01

Every year since 1979, either in sping or in summer, the fishing research vessel 'Walther Herwig' goes to the North Atlantic disposal areas of solid radioactive wastes, and, for comparative purposes, to other areas, in order to collect water samples, plankton and nekton, and, from the deep sea bed, sediment samples and benthos organisms. In addition to data on the radionuclide contents of various media, information about the plankton, nekton and benthos organisms living in those areas and about their biomasses could be gathered. The investigations are aimed at acquiring scientifically founded knowledge of the uptake of radioactive substances by microorganisms, and their migration from the sea bottom to the areas used by man. (orig.) [de

Searches for astrophysical neutrinos with IceCube

International Nuclear Information System (INIS)

Williams, D.

2014-01-01

Powerful astrophysical objects such as active galactic nuclei (AGN), core collapse supernovae and gamma ray bursts (GRBs) are potential sources of the highest energy cosmic rays. Many models of cosmic ray proton acceleration predict a corresponding flux of neutrinos in the TeV-PeV energy range. The detection of astrophysical neutrinos requires the largest neutrino detector ever built: IceCube, a cubic-kilometer array located near the geographic South Pole. IceCube has been collecting data throughout its construction, which was complete in December 2010. Data from the partial IceCube detector have already set interesting limits on astrophysical neutrino fluxes, including stringent limits on neutrino production in GRBs. (authors)

Monitoring the impact of simulated deep-sea mining in Central Indian Basin

Digital Repository Service at National Institute of Oceanography (India)

Sharma, R.; Nath, B.N.; Jaisankar, S.

Monitoring the Impact of Simulated Deep-sea Mining in Central Indian Basin R. SHARMA, B. NAGENDER NATH, AND S. JAI SANKAR National Institute of Oceanography, Dona Paula, Goa, India Monitoring of deep-sea disturbances, natural or man-made, has gained... has shown a partial recovery of the benthic ecosystem, with indications of restoration and recolonization. Keywords deep-sea mining, environmental impact, Central Indian Basin Deep-sea mineral deposits such as the polymetallic nodules and crusts...

Deep-Sea Corals: A New Oceanic Archive

National Research Council Canada - National Science Library

Adkins, Jess

1998-01-01

Deep-sea corals are an extraordinary new archive of deep ocean behavior. The species Desmophyllum cristagalli is a solitary coral composed of uranium rich, density banded aragonite that I have calibrated for several paleoclimate tracers...

Antifouling potentials of eight deep-sea-derived fungi from the South China Sea.

Science.gov (United States)

Zhang, Xiao-Yong; Xu, Xin-Ya; Peng, Jiang; Ma, Chun-Feng; Nong, Xu-Hua; Bao, Jie; Zhang, Guang-Zhao; Qi, Shu-Hua

2014-04-01

Marine-derived microbial secondary metabolites are promising potential sources of nontoxic antifouling agents. The search for environmentally friendly and low-toxic antifouling components guided us to investigate the antifouling potentials of eight novel fungal isolates from deep-sea sediments of the South China Sea. Sixteen crude ethyl acetate extracts of the eight fungal isolates showed distinct antibacterial activity against three marine bacteria (Loktanella hongkongensis UST950701-009, Micrococcus luteus UST950701-006 and Pseudoalteromonas piscida UST010620-005), or significant antilarval activity against larval settlement of bryozoan Bugula neritina. Furthermore, the extract of Aspergillus westerdijkiae DFFSCS013 displayed strong antifouling activity in a field trial lasting 4 months. By further bioassay-guided isolation, five antifouling alkaloids including brevianamide F, circumdatin F and L, notoamide C, and 5-chlorosclerotiamide were isolated from the extract of A. westerdijkiae DFFSCS013. This is the first report about the antifouling potentials of metabolites of the deep-sea-derived fungi from the South China Sea, and the first stage towards the development of non- or low-toxic antifouling agents from deep-sea-derived fungi.

A new procedure for deep sea mining tailings disposal

NARCIS (Netherlands)

Ma, W.; Schott, D.L.; Lodewijks, G.

2017-01-01

Deep sea mining tailings disposal is a new environmental challenge related to water pollution, mineral crust waste handling, and ocean biology. The objective of this paper is to propose a new tailings disposal procedure for the deep sea mining industry. Through comparisons of the tailings disposal

Deep-sea pennatulaceans (sea pens) - recent discoveries, morphological adaptations, and responses to benthic oceanographic parameters

Science.gov (United States)

Williams, G. C.

2015-12-01

Pennatulaceans are sessile, benthic marine organisms that are bathymetrically wide-ranging, from the intertidal to approximately 6300 m in depth, and are conspicuous constituents of deep-sea environments. The vast majority of species are adapted for anchoring in soft sediments by the cylindrical peduncle - a muscular hydrostatic skeleton. However, in the past decade a few species ("Rockpens") have been discovered and described that can attach to hard substratum such as exposed rocky outcrops at depths between 669 and 1969 m, by a plunger-like adaptation of the base of the peduncle. Of the thirty-six known genera, eleven (or 30%) have been recorded from depths greater than 1000 m. The pennatulacean depth record holders are an unidentified species of Umbellula from 6260 m in the Peru-Chile Trench and a recently-discovered and described genus and species, Porcupinella profunda, from 5300 m the Porcupine Abyssal Plain of the northeastern Atlantic. A morphologically-differentiated type of polyp (acrozooid) have recently been discovered and described in two genera of shallow-water coral reef sea pens. Acrozooids apparently represent asexual buds and presumably can detach from the adult to start clonal colonies through asexual budding. Acrozooids are to be expected in deep-sea pennatulaceans, but so far have not been observed below 24 m in depth. Morphological responses at depths greater than 1000 m in deep-sea pennatulaceas include: fewer polyps, larger polyps, elongated stalks, and clustering of polyps along the rachis. Responses to deep-ocean physical parameters and anthropogenic changes that could affect the abundance and distribution of deep-sea pennatulaceans include changes in bottom current flow and food availability, changes in seawater temperature and pH, habitat destruction by fish trawling, and sunken refuse pollution. No evidence of the effects of ocean acidification or other effects of anthropogenic climate change in sea pens of the deep-sea has been

Combined Opto-Acoustical sensor modules for KM3NeT

International Nuclear Information System (INIS)

Enzenhöfer, A.

2013-01-01

KM3NeT is a future multi-cubic-kilometre water Cherenkov neutrino telescope currently entering a first construction phase. It will be located in the Mediterranean Sea and comprise about 600 vertical structures called detection units. Each of these detection units has a length of several hundred metres and is anchored to the sea bed on one side and held taut by a buoy on the other side. The detection units are thus subject to permanent movement due to sea currents. Modules holding photosensors and additional equipment are equally distributed along the detection units. The relative positions of the photosensors has to be known with an uncertainty below 20 cm in order to achieve the necessary precision for neutrino astronomy. These positions can be determined with an acoustic positioning system: dedicated acoustic emitters located at known positions and acoustic receivers along each detection unit. This article describes the approach to combine an acoustic receiver with the photosensors inside one detection module using a common power supply and data readout. The advantage of this approach lies in a reduction of underwater connectors and module configurations as well as in the compactification of the detection units integrating the auxiliary devices necessary for their successful operation.

Uptake and distribution of organo-iodine in deep-sea corals.

Science.gov (United States)

Prouty, Nancy G; Roark, E Brendan; Mohon, Leslye M; Chang, Ching-Chih

2018-07-01

Understanding iodine concentration, transport, and bioavailability is essential in evaluating iodine's impact to the environment and its effectiveness as an environmental biogeotracer. While iodine and its radionuclides have proven to be important tracers in geologic and biologic studies, little is known about transport of this element to the deep sea and subsequent uptake in deep-sea coral habitats. Results presented here on deep-sea black coral iodine speciation and iodine isotope variability provides key information on iodine behavior in natural and anthropogenic environments, and its geochemical pathway in the Gulf of Mexico. Organo-iodine is the dominant iodine species in the black corals, demonstrating that binding of iodine to organic matter plays an important role in the transport and transfer of iodine to the deep-sea corals. The identification of growth bands captured in high-resolution scanning electron images (SEM) with synchronous peaks in iodine variability suggest that riverine delivery of terrestrial-derived organo-iodine is the most plausible explanation to account for annual periodicity in the deep-sea coral geochemistry. Whereas previous studies have suggested the presence of annual growth rings in deep-sea corals, this present study provides a mechanism to explain the formation of annual growth bands. Furthermore, deep-sea coral ages based on iodine peak counts agree well with those ages derived from radiocarbon ( 14 C) measurements. These results hold promise for developing chronologies independent of 14 C dating, which is an essential component in constraining reservoir ages and using radiocarbon as a tracer of ocean circulation. Furthermore, the presence of enriched 129 I/ 127 I ratios during the most recent period of skeleton growth is linked to nuclear weapons testing during the 1960s. The sensitivity of the coral skeleton to record changes in surface water 129 I composition provides further evidence that iodine composition and isotope

Uptake and distribution of organo-iodine in deep-sea corals

Science.gov (United States)

Prouty, Nancy G.; Roark, E. Brendan; Mohon, Leslye M.; Chang, Ching-Chih

2018-01-01

Understanding iodine concentration, transport, and bioavailability is essential in evaluating iodine's impact to the environment and its effectiveness as an environmental biogeotracer. While iodine and its radionuclides have proven to be important tracers in geologic and biologic studies, little is known about transport of this element to the deep sea and subsequent uptake in deep-sea coral habitats. Results presented here on deep-sea black coral iodine speciation and iodine isotope variability provides key information on iodine behavior in natural and anthropogenic environments, and its geochemical pathway in the Gulf of Mexico. Organo-iodine is the dominant iodine species in the black corals, demonstrating that binding of iodine to organic matter plays an important role in the transport and transfer of iodine to the deep-sea corals. The identification of growth bands captured in high-resolution scanning electron images (SEM) with synchronous peaks in iodine variability suggest that riverine delivery of terrestrial-derived organo-iodine is the most plausible explanation to account for annual periodicity in the deep-sea coral geochemistry. Whereas previous studies have suggested the presence of annual growth rings in deep-sea corals, this present study provides a mechanism to explain the formation of annual growth bands. Furthermore, deep-sea coral ages based on iodine peak counts agree well with those ages derived from radiocarbon (14C) measurements. These results hold promise for developing chronologies independent of 14C dating, which is an essential component in constraining reservoir ages and using radiocarbon as a tracer of ocean circulation. Furthermore, the presence of enriched 129I/127I ratios during the most recent period of skeleton growth is linked to nuclear weapons testing during the 1960s. The sensitivity of the coral skeleton to record changes in surface water 129I composition provides further evidence that iodine composition and isotope

Transcriptomes and expression profiling of deep-sea corals from the Red Sea provide insight into the biology of azooxanthellate corals

OpenAIRE

Yum, L. K.; Baumgarten, S.; Röthig, T.; Roder, C.; Roik, Anna; Michell, C.; Voolstra, C. R.

2017-01-01

Despite the importance of deep-sea corals, our current understanding of their ecology and evolution is limited due to difficulties in sampling and studying deep-sea environments. Moreover, a recent re-evaluation of habitat limitations has been suggested after characterization of deep-sea corals in the Red Sea, where they live at temperatures of above 20??C at low oxygen concentrations. To gain further insight into the biology of deep-sea corals, we produced reference transcriptomes and studie...

40Ar/39Ar studies of deep sea igneous rocks

International Nuclear Information System (INIS)

Seidemann, D.

1978-01-01

An attempt to date deep-sea igneous rocks reliably was made using the 40 Ar/ 39 Ar dating technique. It was determined that the 40 Ar/ 39 Ar incremental release technique could not be used to eliminate the effects of excess radiogenic 40 Ar in deep-sea basalts. Excess 40 Ar is released throughout the extraction temperature range and cannot be distinguished from 40 Ar generated by in situ 40 K decay. The problem of the reduction of K-Ar dates associated with sea water alteration of deep-sea igneous rocks could not be resolved using the 40 Ar/ 39 Ar technique. Irradiation induced 39 Ar loss and/or redistribution in fine-grained and altered igneous rocks results in age spectra that are artifacts of the experimental procedure and only partly reflect the geologic history of the sample. Therefore, caution must be used in attributing significance to age spectra of fine grained and altered deep-sea igneous rocks. Effects of 39 Ar recoil are not important for either medium-grained (or coarser) deep-sea rocks or glasses because only a small fraction of the 39 Ar recoils to channels of easy diffusion, such as intergranular boundaries or cracks, during the irradiation. (author)

Deep Ocean Contribution to Sea Level Rise

Science.gov (United States)

Chang, L.; Sun, W.; Tang, H.; Wang, Q.

2017-12-01

The ocean temperature and salinity change in the upper 2000m can be detected by Argo floats, so we can know the steric height change of the ocean. But the ocean layers above 2000m represent only 50% of the total ocean volume. Although the temperature and salinity change are small compared to the upper ocean, the deep ocean contribution to sea level might be significant because of its large volume. There has been some research on the deep ocean rely on the very sparse situ observation and are limited to decadal and longer-term rates of change. The available observational data in the deep ocean are too spares to determine the temporal variability, and the long-term changes may have a bias. We will use the Argo date and combine the situ data and topographic data to estimate the temperature and salinity of the sea water below 2000m, so we can obtain a monthly data. We will analyze the seasonal and annual change of the steric height change due to the deep ocean between 2005 and 2016. And we will evaluate the result combination the present-day satellite and in situ observing systems. The deep ocean contribution can be inferred indirectly as the difference between the altimetry minus GRACE and Argo-based steric sea level.

Deep sea biophysics

International Nuclear Information System (INIS)

Yayanos, A.A.

1982-01-01

A collection of deep-sea bacterial cultures was completed. Procedures were instituted to shelter the culture collection from accidential warming. A substantial data base on the rates of reproduction of more than 100 strains of bacteria from that collection was obtained from experiments and the analysis of that data was begun. The data on the rates of reproduction were obtained under conditions of temperature and pressure found in the deep sea. The experiments were facilitated by inexpensively fabricated pressure vessels, by the streamlining of the methods for the study of kinetics at high pressures, and by computer-assisted methods. A polybarothermostat was used to study the growth of bacteria along temperature gradients at eight distinct pressures. This device should allow for the study of microbial processes in the temperature field simulating the environment around buried HLW. It is small enough to allow placement in a radiation field in future studies. A flow fluorocytometer was fabricated. This device will be used to determine the DNA content per cell in bacteria grown in laboratory culture and in microorganisms in samples from the ocean. The technique will be tested for its rapidity in determining the concentration of cells (standing stock of microorganisms) in samples from the ocean

NOAA National Deep-Sea Coral and Sponge Database 1842-Present

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's Deep-Sea Coral Research and Technology Program (DSC-RTP) is compiling a national geodatabase of the known locations of deep-sea corals and sponges in U.S....

Plastic microfibre ingestion by deep-sea organisms

Science.gov (United States)

Taylor, M. L.; Gwinnett, C.; Robinson, L. F.; Woodall, L. C.

2016-09-01

Plastic waste is a distinctive indicator of the world-wide impact of anthropogenic activities. Both macro- and micro-plastics are found in the ocean, but as yet little is known about their ultimate fate and their impact on marine ecosystems. In this study we present the first evidence that microplastics are already becoming integrated into deep-water organisms. By examining organisms that live on the deep-sea floor we show that plastic microfibres are ingested and internalised by members of at least three major phyla with different feeding mechanisms. These results demonstrate that, despite its remote location, the deep sea and its fragile habitats are already being exposed to human waste to the extent that diverse organisms are ingesting microplastics.

Digital optical modules for the KM3NeT neutrino telescope

Energy Technology Data Exchange (ETDEWEB)

Kalekin, Oleg [Universitaet Erlangen, ECAP (Germany); Collaboration: ANTARES-KM3NeT-Erlangen-Collaboration

2015-07-01

KM3NeT is multi-cubic-kilometer neutrino telescope under construction in the Mediterranean Sea. In the currently running Phase 1 of the project, almost 30 detection units - 700 m tall vertical structures holding 18 Digital Optical Modules (DOMs) each - will be produced and deployed. A KM3NeT DOM consists of a pressure resistant glass sphere encapsulating 31 photomultiplier tubes of 80 mm diameter, readout electronics and additional instrumentation for calibration and monitoring. The Erlangen Centre for Astroparticle Physics is one of the DOM integration sites of the project. This contribution describes the design, functionality and integration procedure of the KM3NeT DOM.

Sudbury neutrino observatory

International Nuclear Information System (INIS)

Ewan, G.T.; Evans, H.C.; Lee, H.W.

1986-10-01

This report is a supplement to a report (SNO-85-3 (Sudbury Neutrino Observatory)) which contained the results of a feasibility study on the construction of a deep underground neutrino observatory based on a 1000 ton heavy water Cerenkov detector. Neutrinos carry detailed information in their spectra on the reactions taking place deep in the interstellar interior and also provide information on supernova explosions. In addition to their role as astrophysical probes, a knowledge of the properties of neutrinos is crucial to theories of grand unification. The Sudbury Neutrino Observatory is unique in its high sensitivity to electron neutrinos and its ability to detect all other types of neutrinos of energy greater than 2.2 MeV. The results of the July 1985 study indicated that the project is technically feasible in that the proposed detector can measure the direction and energy of electron neutrinos above 7 MeV and the scientific programs will make significant contributions to physics and astrophysics. This present report contains new information obtained since the 1985 feasibility study. The enhanced conversion of neutrinos in the sun and the new physics that could be learned using the heavy water detector are discussed in the physics section. The other sections will discuss progress in the areas of practical importance in achieving the physics objectives such as new techniques to measure, monitor and remove low levels of radioactivity in detector components, ideas on calibration of the detector and so forth. The section entitled Administration contains a membership list of the working groups within the SNO collaboration

Discovery Monday - 'The hunt for the phantom particles: sending neutrinos through the Alps'

CERN Multimedia

2004-01-01

Work on the decay tube for the CERN Neutrinos to Gran Sasso (CNGS) Project. Each second, billions of neutrinos bombard every square centimetre of the Earth's surface and therefore pass through our bodies, without us realising it. These phantom particles only rarely interact with matter. They provide physicists with much food for thought, as they are difficult to 'catch' in detectors. Neutrinos are all the more elusive as they are capable of metamorphosis. There are in fact three types of neutrino, the electron neutrino, the muon neutrino and the tau neutrino, and each can mutate into the other. In 2006 CERN will send a beam of muon neutrinos through the Earth's crust to the Gran Sasso National Laboratory (Italy) some 730 kilometres away, in order to better understand the metamorphoses which the neutrino undergoes. At the next Discovery Monday, light will be shed on the path that these intriguing particles will take to Gran Sasso. You will also learn about the methods physicists use to try and catch them in or...

Potential impact of global climate change on benthic deep-sea microbes.

Science.gov (United States)

Danovaro, Roberto; Corinaldesi, Cinzia; Dell'Anno, Antonio; Rastelli, Eugenio

2017-12-15

Benthic deep-sea environments are the largest ecosystem on Earth, covering ∼65% of the Earth surface. Microbes inhabiting this huge biome at all water depths represent the most abundant biological components and a relevant portion of the biomass of the biosphere, and play a crucial role in global biogeochemical cycles. Increasing evidence suggests that global climate changes are affecting also deep-sea ecosystems, both directly (causing shifts in bottom-water temperature, oxygen concentration and pH) and indirectly (through changes in surface oceans' productivity and in the consequent export of organic matter to the seafloor). However, the responses of the benthic deep-sea biota to such shifts remain largely unknown. This applies particularly to deep-sea microbes, which include bacteria, archaea, microeukaryotes and their viruses. Understanding the potential impacts of global change on the benthic deep-sea microbial assemblages and the consequences on the functioning of the ocean interior is a priority to better forecast the potential consequences at global scale. Here we explore the potential changes in the benthic deep-sea microbiology expected in the coming decades using case studies on specific systems used as test models. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A deep sea community at the Kebrit brine pool in the Red Sea

KAUST Repository

Vestheim, Hege

2015-02-26

Approximately 25 deep sea brine pools occur along the mid axis of the Red Sea. These hypersaline, anoxic, and acidic environments have previously been reported to host diverse microbial communities. We visited the Kebrit brine pool in April 2013 and found macrofauna present just above the brine–seawater interface (~1465 m). In particular, inactive sulfur chimneys had associated epifauna of sea anemones, sabellid type polychaetes, and hydroids, and infauna consisting of capitellid polychaetes, gastropods of the genus Laeviphitus (fam. Elachisinidae), and top snails of the family Cocculinidae. The deep Red Sea generally is regarded as extremely poor in benthos. We hypothesize that the periphery along the Kebrit holds increased biomass and biodiversity that are sustained by prokaryotes associated with the brine pool or co-occurring seeps.

Biogeographic patterns of bacterial microdiversity in Arctic deep-sea sediments (Hausgarten, Fram Strait

Directory of Open Access Journals (Sweden)

Pier Luigi eButtigieg

2015-01-01

Full Text Available Marine bacteria colonising deep-sea sediments beneath the Arctic ocean, a rapidly changing ecosystem, have been shown to exhibit significant biogeographic patterns along transects spanning tens of kilometres and across water depths reaching several thousands of metres (Jacob et al., 2013. Jacob et al. adopted what has become a classical view of microbial diversity based on operational taxonomic units clustered at the 97% sequence identity level of the 16S rRNA gene and observed a very large microbial community replacement at the Hausgarten Long-Term Ecological Research station (Eastern Fram Strait. Here, we revisited these data using the oligotyping approach with the aims of obtaining new insights into ecological and biogeographic patterns associated with bacterial microdiversity in marine sediments and of assessing the level of concordance of these insights with previously obtained results. Variation in oligotype dispersal range, relative abundance, co-occurrence, and taxonomic identity were related to environmental parameters such as water depth, biomass, and sedimentary pigment concentration. This study assesses ecological implications of the new microdiversity-based technique using a well-characterised dataset of high relevance for global change biology.

European Strategy for Accelerator-Based Neutrino Physics

CERN Document Server

Bertolucci, Sergio; Cervera, Anselmo; Donini, Andrea; Dracos, Marcos; Duchesneau, Dominique; Dufour, Fanny; Edgecock, Rob; Efthymiopoulos, Ilias; Gschwendtner, Edda; Kudenko, Yury; Long, Ken; Maalampi, Jukka; Mezzetto, Mauro; Pascoli, Silvia; Palladino, Vittorio; Rondio, Ewa; Rubbia, Andre; Rubbia, Carlo; Stahl, Achim; Stanco, Luca; Thomas, Jenny; Wark, David; Wildner, Elena; Zito, Marco

2012-01-01

Massive neutrinos reveal physics beyond the Standard Model, which could have deep consequences for our understanding of the Universe. Their study should therefore receive the highest level of priority in the European Strategy. The discovery and study of leptonic CP violation and precision studies of the transitions between neutrino flavours require high intensity, high precision, long baseline accelerator neutrino experiments. The community of European neutrino physicists involved in oscillation experiments is strong enough to support a major neutrino long baseline project in Europe, and has an ambitious, competitive and coherent vision to propose. Following the 2006 European Strategy for Particle Physics (ESPP) recommendations, two complementary design studies have been carried out: LAGUNA/LBNO, focused on deep underground detector sites, and EUROnu, focused on high intensity neutrino facilities. LAGUNA LBNO recommends, as first step, a conventional neutrino beam CN2PY from a CERN SPS North Area Neutrino Fac...

Starvation and recovery in the deep-sea methanotroph Methyloprofundus sedimenti

OpenAIRE

Tavormina, Patricia L.; Kellermann, Matthias Y.; Antony, Chakkiath Paul; Tocheva, Elitza I.; Dalleska, Nathan F.; Jensen, Ashley J.; Valentine, David L.; Hinrichs, Kai-Uwe; Jensen, Grant J.; Dubilier, Nicole; Orphan, Victoria J.

2017-01-01

In the deep ocean, the conversion of methane into derived carbon and energy drives the establishment of diverse faunal communities. Yet specific biological mechanisms underlying the introduction of methane-derived carbon into the food web remain poorly described, due to a lack of cultured representative deep-sea methanotrophic prokaryotes. Here, the response of the deep-sea aerobic methanotroph Methyloprofundus sedimenti to methane starvation and recovery was characterized. By combining lipid...

Measuring the neutrino mass hierarchy with the future KM3NeT/ORCA detector

Energy Technology Data Exchange (ETDEWEB)

Hofestaedt, Jannik

2017-02-22

The neutrino mass hierarchy can be determined by measuring the energy- and zenith-angle-dependent oscillation pattern of few-GeV atmospheric neutrinos that have traversed the Earth. This measurement is the main science goal of KM3NeT/ORCA ('Oscillation Research with Cosmics in the Abyss'), a planned multi-megaton underwater Cherenkov detector in the Mediterranean Sea. A key task is the reconstruction of shower-like events induced by electron neutrinos in charged-current interactions, which substantially affect the neutrino mass hierarchy sensitivity. In this thesis, numerous aspects of the expected neutrino detection performance of the planned ORCA detector are investigated. A new reconstruction algorithm for neutrino-induced shower-like events is developed. Excellent reconstruction accuracies are achieved, with a neutrino energy resolution better than 26%/24%, and a median neutrino direction resolution better than 11 /9 for electron neutrinos/antineutrinos in charged-current interactions with energies above 7 GeV. It is shown that these resolutions are close to the reconstruction accuracy limits imposed by intrinsic fluctuations in the Cherenkov light signatures. These intrinsic resolution limits are based on generic assumptions about event reconstruction in Cherenkov detectors and are derived as part of this thesis. Differences in event reconstruction capabilities between water- and ice-based Cherenkov detectors are discussed. The configuration of existing trigger algorithms is optimised for the ORCA detector. Based on the developed shower reconstruction, a detector optimisation study of the photosensor density is performed. In addition, it is shown that optical background noise in the deep Mediterranean Sea is not expected to compromise the feasibility of the neutrino mass hierarchy measurement with ORCA. Together, these investigations contribute significantly to the estimated neutrino mass hierarchy sensitivity of ORCA published in the 'Letter of

LAKE BAIKAL: Underwater neutrino detector

International Nuclear Information System (INIS)

Anon.

1991-01-01

A new underwater detector soon to be deployed in Lake Baikal in Siberia, the world's deepest lake with depths down to 1.7 kilometres, could help probe the deepest mysteries of physics. One of the big unsolved problems of astrophysics is the origin of very energetic cosmic rays. However there are many ideas on how particles could be accelerated by exotic concentrations of matter and provide the majority of the Galaxy's high energy particles. Clarification would come from new detectors picking up the energetic photons and neutrinos from these sources

Dynamic and static elastic moduli of North Sea and deep sea chalk

DEFF Research Database (Denmark)

Gommesen, Lars; Fabricius, Ida Lykke

2001-01-01

We have established an empirical relationship between the dynamic and the static mechanical properties of North Sea and deep sea chalk for a large porosity interval with respect to porosity, effective stress history and textural composition. The chalk investigated is from the Tor and Hod Formatio...

Identification of new deep sea sinuous channels in the eastern Arabian Sea.

Science.gov (United States)

Mishra, Ravi; Pandey, D K; Ramesh, Prerna; Clift, Peter D

2016-01-01

Deep sea channel systems are recognized in most submarine fans worldwide as well as in the geological record. The Indus Fan is the second largest modern submarine fan, having a well-developed active canyon and deep sea channel system. Previous studies from the upper Indus Fan have reported several active channel systems. In the present study, deep sea channel systems were identified within the middle Indus Fan using high resolution multibeam bathymetric data. Prominent morphological features within the survey block include the Raman Seamount and Laxmi Ridge. The origin of the newly discovered channels in the middle fan has been inferred using medium resolution satellite bathymetry data. Interpretation of new data shows that the highly sinuous deep sea channel systems also extend to the east of Laxmi Ridge, as well as to the west of Laxmi Ridge, as previously reported. A decrease in sinuosity southward can be attributed to the morphological constraints imposed by the elevated features. These findings have significance in determining the pathways for active sediment transport systems, as well as their source characterization. The geometry suggests a series of punctuated avulsion events leading to the present array of disconnected channels. Such channels have affected the Laxmi Basin since the Pliocene and are responsible for reworking older fan sediments, resulting in loss of the original erosional signature supplied from the river mouth. This implies that distal fan sediments have experienced significant signal shredding and may not represent the erosion and weathering conditions within the onshore basin at the time of sedimentation.

ANTARES : The first undersea neutrino telescope

NARCIS (Netherlands)

Ageron, M.; Aguilar, J. A.; Al Samarai, I.; Albert, A.; Ameli, F.; Andre, M.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Arnaud, K.; Aslanides, E.; Jesus, A. C. Assis; Astraatmadja, T.; Aubert, J. -J.; Auer, R.; Barbarito, E.; Baret, B.; Basa, S.; Bazzotti, M.; Becherini, Y.; Beltramelli, J.; Bersani, A.; Bertin, V.; Beurthey, S.; Biagi, S.; Bigongiari, C.; Billault, M.; Blaes, R.; Bogazzi, C.; de Botton, N.; Bou-Cabo, M.; Boudahef, B.; Bouwhuis, M. C.; Brown, A. M.; Brunner, J.; Busto, J.; Caillat, L.; Calzas, A.; Camarena, F.; Capone, A.; Caponetto, L.; Carloganu, C.; Carminati, G.; Carmona, E.; Carr, J.; Carton, P. H.; Cassano, B.; Castorina, E.; Cecchini, S.; Ceres, A.; Chaleil, Th; Charvis, Ph; Chauchot, P.; Chiarusi, T.; Circella, M.; Compere, C.; Coniglione, R.; Coppolani, X.; Cosquer, A.; Costantini, H.; Cottini, N.; Coyle, P.; Cuneo, S.; Curtil, C.; D'Amato, C.; Damy, G.; van Dantzig, R.; De Bonis, G.; Decock, G.; Decowski, M. P.; Dekeyser, I.; Delagnes, E.; Desages-Ardellier, F.; Deschamps, A.; Destelle, J. -J.; Di Maria, F.; Dinkespiler, B.; Distefano, C.; Dominique, J. -L.; Donzaud, C.; Dornic, D.; Dorosti, Q.; Drogou, J. -F.; Drouhin, D.; Druillole, F.; Durand, D.; Durand, R.; Eberl, T.; Emanuele, U.; Engelen, J. J.; Ernenwein, J. -P.; Escoffier, S.; Falchini, E.; Favard, S.; Fehr, F.; Feinstein, F.; Ferri, M.; Ferry, S.; Fiorello, C.; Flaminio, V.; Folger, F.; Fritsch, U.; Fuda, J. -L.; Galata, S.; Galeotti, S.; Gay, P.; Gensolen, F.; Giacomelli, G.; Gojak, C.; Gomez-Gonzalez, J. P.; Goret, Ph.; Graf, K.; Guillard, G.; Halladjian, G.; Hallewell, G.; van Haren, H.; Hartmann, B.; Heijboer, A. J.; Heine, E.; Hello, Y.; Henry, S.; Hernandez-Rey, J. J.; Herold, B.; Hoessl, J.; Hogenbirk, J.; Hsu, C. C.; Hubbard, J. R.; Jaquet, M.; Jaspers, M.; de Jong, M.; Jourde, D.; Kadler, M.; Kalantar-Nayestanaki, N.; Kalekin, O.; Kappes, A.; Karg, T.; Karkar, S.; Karolak, M.; Katz, U.; Keller, P.; Kestener, P.; Kok, E.; Kok, H.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kretschmer, W.; Kruijer, A.; Kuch, S.; Kulikovskiy, V.; Lachartre, D.; Lafoux, H.; Lagier, P.; Lahmann, R.; Lahonde-Hamdoun, C.; Lamare, P.; Lambard, G.; Languillat, J-C; Larosa, G.; Lavalle, J.; Le Guen, Y.; Le Provost, H.; LeVanSuu, A.; Lefevre, D.; Legou, T.; Lelaizant, G.; Leveque, C.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Louis, F.; Lucarelli, F.; Lyashuk, V.; Magnier, P.; Mangano, S.; Marcel, A.; Marcelin, M.; Margiotta, A.; Martinez-Mora, J. A.; Masullo, R.; Mazeas, F.; Mazure, A.; Meli, A.; Melissas, M.; Migneco, E.; Mongelli, M.; Montaruli, T.; Morganti, M.; Moscoso, L.; Motz, H.; Musumeci, M.; Naumann, C.; Naumann-Godo, M.; Neff, M.; Niess, V.; Nooren, G. J. L.; Oberski, J. E. J.; Olivetto, C.; Palanque-Delabrouille, N.; Patioselitis, D.; Papaleo, R.; Pavalas, G. E.; Payet, K.; Payre, P.; Peek, H.; Petrovic, J.; Piattelli, P.; Picot-Clemente, N.; Picq, C.; Piret, Y.; Poinsignon, J.; Popa, V.; Pradier, T.; Presani, E.; Prono, G.; Racca, C.; Raia, G.; van Randwijk, J.; Real, D.; Reed, C.; Rethore, F.; Rewiersma, P.; Riccobene, G.; Richardt, C.; Richter, R.; Ricol, J. S.; Rigaud, V.; Roca, V.; Roensch, K.; Rolin, J. -F.; Rostovtsev, A.; Rottura, A.; Roux, J.; Rujoiu, M.; Ruppi, M.; Russo, G. V.; Salesa, F.; Salomon, K.; Sapienza, P.; Schmitt, F.; Schoeck, F.; Schuller, J. -P.; Schuessler, F.; Sciliberto, D.; Shanidze, R.; Shirokov, E.; Simeone, F.; Sottoriva, A.; Spies, A.; Spona, T.; Spurio, M.; Steijger, J. J. M.; Stolarczyk, Th; Streeb, K.; Sulak, L.; Taiuti, M.; Tamburini, C.; Tao, C.; Tasca, L.; Terreni, G.; Tezier, D.; Toscano, S.; Urbano, F.; Valdy, P.; Vallage, B.; Van Elewyck, V.; Vannoni, G.; Vecchi, M.; Venekamp, G.; Verlaat, B.; Vernin, P.; Virique, E.; de Vries, G.; Wijnker, G.; Wobbe, G.; de Wolf, E.; Yakovenko, Y.; Yepes, H.; Zaborov, D.; Zaccone, H.; Zornoza, J. D.; Zuniga, J.; van Wijk, R.

2011-01-01

The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the

Deep sea tests of a prototype of the KM3NeT digital optical module

Science.gov (United States)

Adrián-Martínez, S.; Ageron, M.; Aharonian, F.; Aiello, S.; Albert, A.; Ameli, F.; Anassontzis, E. G.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; de Asmundis, R.; Balasi, K.; Band, H.; Barbarino, G.; Barbarito, E.; Barbato, F.; Baret, B.; Baron, S.; Belias, A.; Berbee, E.; van den Berg, A. M.; Berkien, A.; Bertin, V.; Beurthey, S.; van Beveren, V.; Beverini, N.; Biagi, S.; Bianucci, S.; Billault, M.; Birbas, A.; Boer Rookhuizen, H.; Bormuth, R.; Bouché, V.; Bouhadef, B.; Bourlis, G.; Bouwhuis, M.; Bozza, C.; Bruijn, R.; Brunner, J.; Cacopardo, G.; Caillat, L.; Calamai, M.; Calvo, D.; Capone, A.; Caramete, L.; Caruso, F.; Cecchini, S.; Ceres, A.; Cereseto, R.; Champion, C.; Château, F.; Chiarusi, T.; Christopoulou, B.; Circella, M.; Classen, L.; Cocimano, R.; Colonges, S.; Coniglione, R.; Cosquer, A.; Costa, M.; Coyle, P.; Creusot, A.; Curtil, C.; Cuttone, G.; D'Amato, C.; D'Amico, A.; De Bonis, G.; De Rosa, G.; Deniskina, N.; Destelle, J.-J.; Distefano, C.; Donzaud, C.; Dornic, D.; Dorosti-Hasankiadeh, Q.; Drakopoulou, E.; Drouhin, D.; Drury, L.; Durand, D.; Eberl, T.; Eleftheriadis, C.; Elsaesser, D.; Enzenhöfer, A.; Fermani, P.; Fusco, L. A.; Gajana, D.; Gal, T.; Galatà, S.; Gallo, F.; Garufi, F.; Gebyehu, M.; Giordano, V.; Gizani, N.; Gracia Ruiz, R.; Graf, K.; Grasso, R.; Grella, G.; Grmek, A.; Habel, R.; van Haren, H.; Heid, T.; Heijboer, A.; Heine, E.; Henry, S.; Hernández-Rey, J. J.; Herold, B.; Hevinga, M. A.; van der Hoek, M.; Hofestädt, J.; Hogenbirk, J.; Hugon, C.; Hößl, J.; Imbesi, M.; James, C.; Jansweijer, P.; Jochum, J.; de Jong, M.; Kadler, M.; Kalekin, O.; Kappes, A.; Kappos, E.; Katz, U.; Kavatsyuk, O.; Keller, P.; Kieft, G.; Koffeman, E.; Kok, H.; Kooijman, P.; Koopstra, J.; Korporaal, A.; Kouchner, A.; Koutsoukos, S.; Kreykenbohm, I.; Kulikovskiy, V.; Lahmann, R.; Lamare, P.; Larosa, G.; Lattuada, D.; Le Provost, H.; Leisos, A.; Lenis, D.; Leonora, E.; Lindsey Clark, M.; Liolios, A.; Llorens Alvarez, C. D.; Löhner, H.; Lo Presti, D.; Louis, F.; Maccioni, E.; Mannheim, K.; Manolopoulos, K.; Margiotta, A.; Mariş, O.; Markou, C.; Martínez-Mora, J. A.; Martini, A.; Masullo, R.; Michael, T.; Migliozzi, P.; Migneco, E.; Miraglia, A.; Mollo, C.; Mongelli, M.; Morganti, M.; Mos, S.; Moudden, Y.; Musico, P.; Musumeci, M.; Nicolaou, C.; Nicolau, C. A.; Orlando, A.; Orzelli, A.; Papageorgiou, K.; Papaikonomou, A.; Papaleo, R.; Păvălaş, G. E.; Peek, H.; Pellegrino, C.; Pellegriti, M. G.; Perrina, C.; Petridou, C.; Piattelli, P.; Pikounis, K.; Popa, V.; Pradier, Th.; Priede, M.; Pühlhofer, G.; Pulvirenti, S.; Racca, C.; Raffaelli, F.; Randazzo, N.; Rapidis, P. A.; Razis, P.; Real, D.; Resvanis, L.; Reubelt, J.; Riccobene, G.; Rovelli, A.; Royon, J.; Saldaña, M.; Samtleben, D. F. E.; Sanguineti, M.; Santangelo, A.; Sapienza, P.; Savvidis, I.; Schmelling, J.; Schnabel, J.; Sedita, M.; Seitz, T.; Sgura, I.; Simeone, F.; Siotis, I.; Sipala, V.; Solazzo, M.; Spitaleri, A.; Spurio, M.; Stavropoulos, G.; Steijger, J.; Stolarczyk, T.; Stransky, D.; Taiuti, M.; Terreni, G.; Tézier, D.; Théraube, S.; Thompson, L. F.; Timmer, P.; Trapierakis, H. I.; Trasatti, L.; Trovato, A.; Tselengidou, M.; Tsirigotis, A.; Tzamarias, S.; Tzamariudaki, E.; Vallage, B.; Van Elewyck, V.; Vermeulen, J.; Vernin, P.; Viola, S.; Vivolo, D.; Werneke, P.; Wiggers, L.; Wilms, J.; de Wolf, E.; van Wooning, R. H. L.; Yatkin, K.; Zachariadou, K.; Zonca, E.; Zornoza, J. D.; Zúñiga, J.; Zwart, A.

2014-09-01

The first prototype of a photo-detection unit of the future KM3NeT neutrino telescope has been deployed in the deep waters of the Mediterranean Sea. This digital optical module has a novel design with a very large photocathode area segmented by the use of 31 three inch photomultiplier tubes. It has been integrated in the ANTARES detector for in-situ testing and validation. This paper reports on the first months of data taking and rate measurements. The analysis results highlight the capabilities of the new module design in terms of background suppression and signal recognition. The directionality of the optical module enables the recognition of multiple Cherenkov photons from the same $^{40}$K decay and the localization bioluminescent activity in the neighbourhood. The single unit can cleanly identify atmospheric muons and provide sensitivity to the muon arrival directions.

Deep sea tests of a prototype of the KM3NeT digital optical module

International Nuclear Information System (INIS)

Adrian-Martinez, S.; Ardid, M.; Llorens Alvarez, C.D.; Saldana, M.; Ageron, M.; Bertin, V.; Beurthey, S.; Billault, M.; Brunner, J.; Caillat, L.; Cosquer, A.; Coyle, P.; Curtil, C.; Destelle, J.J.; Dornic, D.; Gallo, F.; Henry, S.; Keller, P.; Lamare, P.; Royon, J.; Solazzo, M.; Tezier, D.; Theraube, S.; Yatkin, K.; Aharonian, F.; Drury, L.; Aiello, S.; Giordano, V.; Leonora, E.; Randazzo, N.; Sipala, V.; Albert, A.; Drouhin, D.; Racca, C.; Ameli, F.; De Bonis, G.; Nicolau, C.A.; Simeone, F.; Anassontzis, E.G.; Anghinolfi, M.; Cereseto, R.; Hugon, C.; Kulikovskiy, V.; Musico, P.; Orzelli, A.; Anton, G.; Classen, L.; Eberl, T.; Enzenhoefer, A.; Gal, T.; Graf, K.; Heid, T.; Herold, B.; Hofestaedt, J.; Hoessl, J.; James, C.; Kalekin, O.; Kappes, A.; Katz, U.; Lahmann, R.; Reubelt, J.; Schnabel, J.; Seitz, T.; Stransky, D.; Tselengidou, M.; Anvar, S.; Chateau, F.; Durand, D.; Le Provost, H.; Louis, F.; Moudden, Y.; Zonca, E.; Asmundis, R. de; Deniskina, N.; Migliozzi, P.; Mollo, C.; Balasi, K.; Drakopoulou, E.; Markou, C.; Pikounis, K.; Siotis, I.; Stavropoulos, G.; Tzamariudaki, E.; Band, H.; Berbee, E.; Berkien, A.; Beveren, V. van; Boer Rookhuizen, H.; Bouwhuis, M.; Gajana, D.; Gebyehu, M.; Heijboer, A.; Heine, E.; Hoek, M. van der; Hogenbirk, J.; Jansweijer, P.; Kieft, G.; Kok, H.; Koopstra, J.; Korporaal, A.; Michael, T.; Mos, S.; Peek, H.; Schmelling, J.; Steijger, J.; Timmer, P.; Vermeulen, J.; Werneke, P.; Wiggers, L.; Zwart, A.; Barbarino, G.; Barbato, F.; De Rosa, G.; Garufi, F.; Vivolo, D.; Barbarito, E.; Ceres, A.; Circella, M.; Mongelli, M.; Sgura, I.; Baret, B.; Baron, S.; Champion, C.; Colonges, S.; Creusot, A.; Galata, S.; Gracia Ruiz, R.; Kouchner, A.; Lindsey Clark, M.; Van Elewyck, V.; Belias, A.; Rapidis, P.A.; Trapierakis, H.I.; Berg, A.M. van den; Dorosti-Hasankiadeh, Q.; Hevinga, M.A.; Kavatsyuk, O.; Loehner, H.; Wooning, R.H.L. van; Beverini, N.; Biagi, S.; Cecchini, S.; Fusco, L.A.; Margiotta, A.; Spurio, M.; Bianucci, S.; Bouhadef, B.; Calamai, M.; Morganti, M.; Raffaelli, F.; Terreni, G.; Birbas, A.; Bourlis, G.; Christopoulou, B.; Gizani, N.; Leisos, A.; Lenis, D.; Tsirigotis, A.; Tzamarias, S.; Bormuth, R.; Jong, M. de; Samtleben, D.F.E.; Bouche, V.; Fermani, P.; Masullo, R.; Perrina, C.; Bozza, C.; Grella, G.; Bruijn, R.; Koffeman, E.; Wolf, E. de; Cacopardo, G.; Caruso, F.; Cocimano, R.; Coniglione, R.; Costa, M.; Cuttone, G.; D'Amato, C.; D'Amico, A.; Distefano, C.; Grasso, R.; Grmek, A.; Imbesi, M.; Larosa, G.; Lattuada, D.; Migneco, E.; Miraglia, A.; Musumeci, M.; Orlando, A.; Papaleo, R.; Pellegrino, C.; Pellegriti, M.G.; Piattelli, P.

2014-01-01

The first prototype of a photo-detection unit of the future KM3NeT neutrino telescope has been deployed in the deep waters of the Mediterranean Sea. This digital optical module has a novel design with a very large photocathode area segmented by the use of 31 three inch photomultiplier tubes. It has been integrated in the ANTARES detector for in-situ testing and validation. This paper reports on the first months of data taking and rate measurements. The analysis results highlight the capabilities of the new module design in terms of background suppression and signal recognition. The directionality of the optical module enables the recognition of multiple Cherenkov photons from the same 40 K decay and the localisation of bioluminescent activity in the neighbourhood. The single unit can cleanly identify atmospheric muons and provide sensitivity to the muon arrival directions. (orig.)

A deep sea community at the Kebrit brine pool in the Red Sea

KAUST Repository

Vestheim, Hege; Kaartvedt, Stein

2015-01-01

Approximately 25 deep sea brine pools occur along the mid axis of the Red Sea. These hypersaline, anoxic, and acidic environments have previously been reported to host diverse microbial communities. We visited the Kebrit brine pool in April 2013

Seawater Carbonate Chemistry of Deep-sea Coral Beds off the Northwestern Hawaiian Islands

Science.gov (United States)

Brooks, J.; Shamberger, K.; Roark, E. B.; Miller, K.; Baco-Taylor, A.

2016-02-01

Many species of deep-sea octocorals produce calcium carbonate (CaCO3) skeletons and form coral beds that support diverse ecosystems crucial to fisheries. The geochemistry of deep-sea coral skeletons can provide valuable paleoceanographic information on ocean circulation and nutrient cycling. Deep-sea corals in the older bottom waters of the Pacific are naturally exposed to higher carbon dioxide (CO2) concentrations and lower pH than in the Atlantic where much of the previous deep-sea coral work has occurred. Therefore, some Pacific deep-sea corals may live and calcify in waters that are corrosive to their skeletons, but there have been few current seawater carbonate chemistry measurements of the waters surrounding deep-sea coral beds to assess this. The input of anthropogenic atmospheric CO2 known as ocean acidification (OA) lowers ocean pH and causes an expansion of these corrosive waters. Seawater carbonate chemistry must be characterized before accurate predictions can be made for the effects of OA on these important ecosystems. Total Alkalinity (TA) and Dissolved Inorganic Carbon (DIC) samples were collected in the fall of 2014 and 2015 from the surface to 1450 m depth off the Northwestern Hawaiian Island chain where deep-sea octocorals are found. The partial pressure of CO2 increased and pH, calcite saturation state (Ωca) and aragonite saturation state (Ωar) decreased with increasing latitude and depth. Notably, waters were undersaturated with respect to calcite and aragonite (Ωca and Ωar less than 1) below 800 m and 500 m, respectively. Therefore, deep-sea corals below these depths must calcify in waters that are thermodynamically favorable for CaCO3 dissolution. How deep-sea octocorals cope with such adverse seawater chemistry is critical to understanding future effects of OA. It is not known whether OA is currently negatively impacting deep-sea octocorals, but their naturally acidified environments could make them particularly susceptible to OA.

Ecosystem function and services provided by the deep sea

Science.gov (United States)

Thurber, A. R.; Sweetman, A. K.; Narayanaswamy, B. E.; Jones, D. O. B.; Ingels, J.; Hansman, R. L.

2014-07-01

The deep sea is often viewed as a vast, dark, remote, and inhospitable environment, yet the deep ocean and seafloor are crucial to our lives through the services that they provide. Our understanding of how the deep sea functions remains limited, but when treated synoptically, a diversity of supporting, provisioning, regulating and cultural services becomes apparent. The biological pump transports carbon from the atmosphere into deep-ocean water masses that are separated over prolonged periods, reducing the impact of anthropogenic carbon release. Microbial oxidation of methane keeps another potent greenhouse gas out of the atmosphere while trapping carbon in authigenic carbonates. Nutrient regeneration by all faunal size classes provides the elements necessary for fueling surface productivity and fisheries, and microbial processes detoxify a diversity of compounds. Each of these processes occur on a very small scale, yet considering the vast area over which they occur they become important for the global functioning of the ocean. The deep sea also provides a wealth of resources, including fish stocks, enormous bioprospecting potential, and elements and energy reserves that are currently being extracted and will be increasingly important in the near future. Society benefits from the intrigue and mystery, the strange life forms, and the great unknown that has acted as a muse for inspiration and imagination since near the beginning of civilization. While many functions occur on the scale of microns to meters and timescales up to years, the derived services that result are only useful after centuries of integrated activity. This vast dark habitat, which covers the majority of the globe, harbors processes that directly impact humans in a variety of ways; however, the same traits that differentiate it from terrestrial or shallow marine systems also result in a greater need for integrated spatial and temporal understanding as it experiences increased use by society. In

Exchanges between the shelf and the deep Black Sea: an integrated analysis of physical mechanisms

Science.gov (United States)

Shapiro, Georgy; Wobus, Fred; Zatsepin, Andrei; Akivis, Tatiana; Zhou, Feng

2017-04-01

% of shelf waters, were moved into the deep-sea region, respectively. Due to the high intensity of cross-shelf exchanges, the average renewal time for the NW shelf in the Black Sea was only 28 days in the summer of 2005 (Zhou et al. 2014). Mechanism 3: exchanges due to assisted cascading. Using the model run for 2003 as an example, we examine the fate of the tracer after 5.5 months of model integration. At 100m depth we identify four anti-cyclonic eddies: two eddies west of the Crimea peninsula, one north of Sinop and one west of Batumi. These eddies can be seen to assist cascading into the basin interior of cold waters formed on a shallow NW shelf to a depth greater than at which they were originally formed. The important result is that for many of the 24 studied years a significant proportion of dense shelf water does not cascade locally off the NW shelf, but is transported by the Rim Current over hundreds of kilometres before cascading into the deep basin in the southern and southeastern Black Sea. This work has been supported by EU FP7 PERSEUS, EU H2020 Sea Basin checkpoints Lot4 - Black Sea and a number of Chinese and Russian national projects. References Zhou, F., G. I. Shapiro, and F. Wobus, 2014: Cross-shelf exchange in the northwestern Black Sea. Journal of Geophysical Research: Oceans, 119, 2143-2164.

Solar neutrinos

International Nuclear Information System (INIS)

Schatzman, E.

1983-01-01

The solar energy is produced by a series of nuclear reactions taking place in the deep interior of the sun. Some of these reactions produce neutrinos which may be detected, the proper detection system being available. The results of the Davis experiment (with 37 Cl) are given, showing a deficiency in the solar neutrino flux. The relevant explanation is either a property of the neutrino or an important change in the physics of the solar models. The prospect of a new experiment (with 71 Ga) is important as it will decide which of the two explanations is correct [fr

Deep-Sea Soft Coral Habitat Suitability

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Deep-sea corals, also known as cold water corals, create complex communities that provide habitat for a variety of invertebrate and fish species, such as grouper,...

Deep-Sea Stony Coral Habitat Suitability

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Deep-sea corals, also known as cold water corals, create complex communities that provide habitat for a variety of invertebrate and fish species, such as grouper,...

Factors governing the deep ventilation of the Red Sea

KAUST Repository

Papadopoulos, Vassilis P.

2015-11-19

A variety of data based on hydrographic measurements, satellite observations, reanalysis databases, and meteorological observations are used to explore the interannual variability and factors governing the deep water formation in the northern Red Sea. Historical and recent hydrographic data consistently indicate that the ventilation of the near-bottom layer in the Red Sea is a robust feature of the thermohaline circulation. Dense water capable to reach the bottom layers of the Red Sea can be regularly produced mostly inside the Gulfs of Aqaba and Suez. Occasionally, during colder than usual winters, deep water formation may also take place over coastal areas in the northernmost end of the open Red Sea just outside the Gulfs of Aqaba and Suez. However, the origin as well as the amount of deep waters exhibit considerable interannual variability depending not only on atmospheric forcing but also on the water circulation over the northern Red Sea. Analysis of several recent winters shows that the strength of the cyclonic gyre prevailing in the northernmost part of the basin can effectively influence the sea surface temperature (SST) and intensify or moderate the winter surface cooling. Upwelling associated with periods of persistent gyre circulation lowers the SST over the northernmost part of the Red Sea and can produce colder than normal winter SST even without extreme heat loss by the sea surface. In addition, the occasional persistence of the cyclonic gyre feeds the surface layers of the northern Red Sea with nutrients, considerably increasing the phytoplankton biomass.

Studies of the reproductive biology of deep sea megabenthos VIII. Biochemical and calorific content of the reproductive organs of deep sea holothurians

International Nuclear Information System (INIS)

Tyler, P.A.; Walker, M.

1987-01-01

The data for protein, lipid, carbohydrate and ash content of the ovary, testes, gut and body wall of a variety of deep sea holothurians are presented. The dominant biochemical is insoluble protein in all tissues followed by lipid in the ovary. The ash content was lowest in the gonads and highest in the body wall of most species. The mean calorific content of the species studied is 25.08Jmg -1 thus representing a significant energy store in the deep sea. The data suggest active metabolic pathways in these species which may pass radionuclides to the developing gametes and after spawning to dispersal in deep waters. (author)

Probing Neutrino Properties with Long-Baseline Neutrino Beams

International Nuclear Information System (INIS)

Marino, Alysia

2015-01-01

This final report on an Early Career Award grant began in April 15, 2010 and concluded on April 14, 2015. Alysia Marino's research is focussed on making precise measurements of neutrino properties using intense accelerator-generated neutrino beams. As a part of this grant, she is collaborating on the Tokai-to-Kamioka (T2K) long-baseline neutrino experiment, currently taking data in Japan, and on the Deep Underground Neutrino Experiment (DUNE) design effort for a future Long-Baseline Neutrino Facility (LBNF) in the US. She is also a member of the NA61/SHINE particle production experiment at CERN, but as that effort is supported by other funds, it will not be discussed further here. T2K was designed to search for the disappearance of muon neutrinos (?_?) and the appearance of electron neutrinos (?_e), using a beam of muon neutrino beam that travels 295 km across Japan towards the Super-Kamiokande detector. In 2011 T2K first reported indications of ?_e appearance, a previously unobserved mode of neutrino oscillations. In the past year, T2K has published a combined analysis of ?_? disappearance and ?_e appearance, and began collecting taking data with a beam of anti-neutrinos, instead of neutrinos, to search for hints of violation of the CP symmetry of the universe. The proposed DUNE experiment has similar physics goals to T2K, but will be much more sensitive due to its more massive detectors and new higher-intensity neutrino beam. This effort will be very high-priority particle physics project in the US over the next decade.

Structure, functioning, and cumulative stressors of Mediterranean deep-sea ecosystems

Science.gov (United States)

Tecchio, Samuele; Coll, Marta; Sardà, Francisco

2015-06-01

Environmental stressors, such as climate fluctuations, and anthropogenic stressors, such as fishing, are of major concern for the management of deep-sea ecosystems. Deep-water habitats are limited by primary productivity and are mainly dependent on the vertical input of organic matter from the surface. Global change over the latest decades is imparting variations in primary productivity levels across oceans, and thus it has an impact on the amount of organic matter landing on the deep seafloor. In addition, anthropogenic impacts are now reaching the deep ocean. The Mediterranean Sea, the largest enclosed basin on the planet, is not an exception. However, ecosystem-level studies of response to varying food input and anthropogenic stressors on deep-sea ecosystems are still scant. We present here a comparative ecological network analysis of three food webs of the deep Mediterranean Sea, with contrasting trophic structure. After modelling the flows of these food webs with the Ecopath with Ecosim approach, we compared indicators of network structure and functioning. We then developed temporal dynamic simulations varying the organic matter input to evaluate its potential effect. Results show that, following the west-to-east gradient in the Mediterranean Sea of marine snow input, organic matter recycling increases, net production decreases to negative values and trophic organisation is overall reduced. The levels of food-web activity followed the gradient of organic matter availability at the seafloor, confirming that deep-water ecosystems directly depend on marine snow and are therefore influenced by variations of energy input, such as climate-driven changes. In addition, simulations of varying marine snow arrival at the seafloor, combined with the hypothesis of a possible fishery expansion on the lower continental slope in the western basin, evidence that the trawling fishery may pose an impact which could be an order of magnitude stronger than a climate

Application of Low cost Spirulina growth medium using Deep sea water

Science.gov (United States)

Lim, Dae-hack; Kim, Bong-ju; Lee, Sung-jae; Choi, Nag-chul; Park, Cheon-young

2017-04-01

Deep-sea water has a relatively constant temperature, abundant nutrients such as calcium, magnesium, nitrates, and phosphates, etc., and stable water quality, even though there might be some variations of their compositions according to collection places. Thus, deep-sea water would be a good substrate for algal growth and biomass production since it contains various nutrients, including a fluorescent red pigment, and β-carotene, etc. The aim of this study was to investigate the economics of a culture condition through comparative analysis to Spirulina platensis growth characteristic under various medium conditions for cost-effective production of Spirulina sp.. Growth experiments were performed with S. platensis under various culture medium conditions (deep sea water + SP medium). Growth tests for culture medium demonstrated that the deep sea water to SP medium ratio of 50:50(W/W) was effective in S. platensis with the maximum biomass (1.35g/L) and minimum medium making cost per production mass (133.28 KRW/g). Parameter estimation of bio-kinetics (maximum growth rate and yield) for low cost medium results showed that the maximum growth rate and yield of N, P, K were obtained under deep sea water to SP medium ratio of 50:50(W/W) of 0.057 1/day and 0.151, 0.076, 0.123, respectively. Acknowledgment : "This research was a part of the project titled 'Development of microalgae culture technique for cosmetic materials based on ocean deep sea water(20160297)', funded by the Ministry of Oceans and Fisheries, Korea."

Man and the last great wilderness: human impact on the deep sea.

Directory of Open Access Journals (Sweden)

Eva Ramirez-Llodra

Full Text Available The deep sea, the largest ecosystem on Earth and one of the least studied, harbours high biodiversity and provides a wealth of resources. Although humans have used the oceans for millennia, technological developments now allow exploitation of fisheries resources, hydrocarbons and minerals below 2000 m depth. The remoteness of the deep seafloor has promoted the disposal of residues and litter. Ocean acidification and climate change now bring a new dimension of global effects. Thus the challenges facing the deep sea are large and accelerating, providing a new imperative for the science community, industry and national and international organizations to work together to develop successful exploitation management and conservation of the deep-sea ecosystem. This paper provides scientific expert judgement and a semi-quantitative analysis of past, present and future impacts of human-related activities on global deep-sea habitats within three categories: disposal, exploitation and climate change. The analysis is the result of a Census of Marine Life--SYNDEEP workshop (September 2008. A detailed review of known impacts and their effects is provided. The analysis shows how, in recent decades, the most significant anthropogenic activities that affect the deep sea have evolved from mainly disposal (past to exploitation (present. We predict that from now and into the future, increases in atmospheric CO(2 and facets and consequences of climate change will have the most impact on deep-sea habitats and their fauna. Synergies between different anthropogenic pressures and associated effects are discussed, indicating that most synergies are related to increased atmospheric CO(2 and climate change effects. We identify deep-sea ecosystems we believe are at higher risk from human impacts in the near future: benthic communities on sedimentary upper slopes, cold-water corals, canyon benthic communities and seamount pelagic and benthic communities. We finalise this

Man and the Last Great Wilderness: Human Impact on the Deep Sea

Science.gov (United States)

Ramirez-Llodra, Eva; Tyler, Paul A.; Baker, Maria C.; Bergstad, Odd Aksel; Clark, Malcolm R.; Escobar, Elva; Levin, Lisa A.; Menot, Lenaick; Rowden, Ashley A.; Smith, Craig R.; Van Dover, Cindy L.

2011-01-01

The deep sea, the largest ecosystem on Earth and one of the least studied, harbours high biodiversity and provides a wealth of resources. Although humans have used the oceans for millennia, technological developments now allow exploitation of fisheries resources, hydrocarbons and minerals below 2000 m depth. The remoteness of the deep seafloor has promoted the disposal of residues and litter. Ocean acidification and climate change now bring a new dimension of global effects. Thus the challenges facing the deep sea are large and accelerating, providing a new imperative for the science community, industry and national and international organizations to work together to develop successful exploitation management and conservation of the deep-sea ecosystem. This paper provides scientific expert judgement and a semi-quantitative analysis of past, present and future impacts of human-related activities on global deep-sea habitats within three categories: disposal, exploitation and climate change. The analysis is the result of a Census of Marine Life – SYNDEEP workshop (September 2008). A detailed review of known impacts and their effects is provided. The analysis shows how, in recent decades, the most significant anthropogenic activities that affect the deep sea have evolved from mainly disposal (past) to exploitation (present). We predict that from now and into the future, increases in atmospheric CO2 and facets and consequences of climate change will have the most impact on deep-sea habitats and their fauna. Synergies between different anthropogenic pressures and associated effects are discussed, indicating that most synergies are related to increased atmospheric CO2 and climate change effects. We identify deep-sea ecosystems we believe are at higher risk from human impacts in the near future: benthic communities on sedimentary upper slopes, cold-water corals, canyon benthic communities and seamount pelagic and benthic communities. We finalise this review with a short

Wroclaw neutrino event generator

International Nuclear Information System (INIS)

Nowak, J A

2006-01-01

A neutrino event generator developed by the Wroclaw Neutrino Group is described. The physical models included in the generator are discussed and illustrated with the results of simulations. The considered processes are quasi-elastic scattering and pion production modelled by combining the Δ resonance excitation and deep inelastic scattering

Photomultiplier characteristics considerations for the deep underwater muon and neutrino detection system

International Nuclear Information System (INIS)

Leskovar, B.

1980-01-01

The results of an investigation of the characteristics of photomultipliers for the Deep Underwater Muon and Neutrino Detection (DUMAND) System are discussed. The pulse-height resolution, the afterpulsing phenomena and the gain sensitivity to the ambient magnetic field have been determined for large photocathode area photomultipliers. Furthermore, the transient time difference, the single photoelectron time spread, and the collection and photocathode quantum efficiency uniformity as a function of the position of the photocathode sensing area have been reviewed. Finally, an attempt has been made to estimate the photomultiplier reliability and its lifetime

Countermeasure Study on Deep-sea Oil Exploitation in the South China Sea——A Comparison between Deep-sea Oil Exploitation in the South China Sea and the Gulf of Mexico

Science.gov (United States)

Zhao, Hui; Qiu, Weiting; Qu, Weilu

2018-02-01

The unpromising situation of terrestrial oil resources makes the deep-sea oil industry become an important development strategy. The South China Sea has a vast sea area with a wide distribution of oil and gas resources, but there is a phenomenon that exploration and census rates and oil exploitation are low. In order to solve the above problems, this article analyzes the geology, oil and gas exploration and exploration equipment in the South China Sea and the Gulf of Mexico. Comparing the political environment of China and the United States energy industry and the economic environment of oil companies, this article points out China’s deep-sea oil exploration and mining problems that may exist. Finally, the feasibility of oil exploration and exploitation in the South China Sea is put forward, which will provide reference to improve the conditions of oil exploration in the South China Sea and promoting the stable development of China’s oil industry.

Bipolar gene flow in deep-sea benthic foraminifera

DEFF Research Database (Denmark)

Pawlowski, J.; Fahrni, J.; Lecroq, B.

2007-01-01

Despite its often featureless appearance, the deep-ocean floor includes some of the most diverse habitats on Earth. However, the accurate assessment of global deep-sea diversity is impeded by a paucity of data on the geographical ranges of bottom-dwelling species, particularly at the genetic leve...

Decoherence in Neutrino Propagation Through Matter, and Bounds from IceCube/DeepCore

Energy Technology Data Exchange (ETDEWEB)

Coloma, Pilar [Fermilab; Lopez-Pavon, Jacobo [CERN; Martinez-Soler, Ivan [Madrid, IFT; Nunokawa, Hiroshi [Rio de Janeiro, Pont. U. Catol.

2018-03-12

We revisit neutrino oscillations in matter considering the open quantum system framework which allows to introduce possible decoherence effects generated by New Physics in a phenomenological manner. We assume that the decoherence parameters $\\gamma_{ij}$ may depend on the neutrino energy, as $\\gamma_{ij}=\\gamma_{ij}^{0}(E/\\text{GeV})^n$ $(n = 0,\\pm1,\\pm2) $. The case of non-uniform matter is studied in detail, both within the adiabatic approximation and in the more general non-adiabatic case. In particular, we develop a consistent formalism to study the non-adiabatic case dividing the matter profile into an arbitrary number of layers of constant densities. This formalism is then applied to explore the sensitivity of IceCube and DeepCore to this type of effects. Our study is the first atmospheric neutrino analysis where a consistent treatment of the matter effects in the three-neutrino case is performed in presence of decoherence. We show that matter effects are indeed extremely relevant in this context. We find that IceCube is able to considerably improve over current bounds in the solar sector ($\\gamma_{21}$) and in the atmospheric sector ($\\gamma_{31}$ and $\\gamma_{32}$) for $n=0,1,2$ and, in particular, by several orders of magnitude (between 3 and 9) for the $n=1,2$ cases. For $n=0$ we find $\\gamma_{32},\\gamma_{31}< 4.0\\cdot10^{-24} (1.3\\cdot10^{-24})$ GeV and $\\gamma_{21}<1.3\\cdot10^{-24} (4.1\\cdot10^{-24})$ GeV, for normal (inverted) mass ordering.

Deep sea mega-geomorphology: Progress and problems

Science.gov (United States)

Bryan, W. B.

1985-01-01

Historically, marine geologists have always worked with mega-scale morphology. This is a consequence both of the scale of the ocean basins and of the low resolution of the observational remote sensing tools available until very recently. In fact, studies of deep sea morphology have suffered from a serious gap in observational scale. Traditional wide-beam echo sounding gave images on a scale of miles, while deep sea photography has been limited to scales of a few tens of meters. Recent development of modern narrow-beam echo sounding coupled with computer-controlled swath mapping systems, and development of high-resolution deep-towed side-scan sonar, are rapidly filling in the scale gap. These technologies also can resolve morphologic detail on a scale of a few meters or less. As has also been true in planetary imaging projects, the ability to observe phenomena over a range of scales has proved very effective in both defining processes and in placing them in proper context.

A new procedure for deep sea mining tailings disposal

OpenAIRE

Ma, W.; Schott, D.L.; Lodewijks, G.

2017-01-01

Deep sea mining tailings disposal is a new environmental challenge related to water pollution, mineral crust waste handling, and ocean biology. The objective of this paper is to propose a new tailings disposal procedure for the deep sea mining industry. Through comparisons of the tailings disposal methods which exist in on-land mining and the coastal mining fields, a new tailings disposal procedure, i.e., the submarine–backfill–dam–reuse (SBDR) tailings disposal procedure, is proposed. It com...

CONFERENCE: Neutrino mass

International Nuclear Information System (INIS)

Anon.

1988-01-01

The successes in capturing neutrinos from last year's supernova underlined the usefulness of large underground detectors for this sort of physics, and ambitious new projects are now in the pipeline. Meanwhile another approach to cosmic neutrino detection, carefully prepared during the past decade, has now taken its first experimental steps. DUMAND - Deep Underwater Muon and Neutrino Detector - aims to use the ocean as the active medium, tracking particles with arrays of photomultipliers picking up the tiny nanosecond flashes of blue Cherenkov light emitted by cosmic particles as they pass through seawater

CONFERENCE: Neutrino mass

Energy Technology Data Exchange (ETDEWEB)

Anon.

1988-06-15

The successes in capturing neutrinos from last year's supernova underlined the usefulness of large underground detectors for this sort of physics, and ambitious new projects are now in the pipeline. Meanwhile another approach to cosmic neutrino detection, carefully prepared during the past decade, has now taken its first experimental steps. DUMAND - Deep Underwater Muon and Neutrino Detector - aims to use the ocean as the active medium, tracking particles with arrays of photomultipliers picking up the tiny nanosecond flashes of blue Cherenkov light emitted by cosmic particles as they pass through seawater.

Measurement of sin2θw and ϱ in deep inelastic neutrino-nucleon scattering

Science.gov (United States)

Reutens, P. G.; Merritt, F. S.; Macfarlane, D. B.; Messner, R. L.; Novikoff, D. B.; Purohit, M. V.; Blair, R. E.; Sciulli, F. J.; Shaevitz, M. H.; Fisk, H. E.; Fukushima, Y.; Jin, B. N.; Kondo, T.; Rapidis, P. A.; Yovanovitch, D. D.; Bodek, A.; Coleman, R. N.; Marsh, W. L.; Fackler, O. D.; Jenkins, K. A.

1985-03-01

We describe a high statistics measurement from deep inelastic neutrino-nucleon scattering of the electroweak parameters ϱ and sin2θw, performed in the Fermilab narrow-band neutrino beam. Our measurement uses a radius-dependent cut in y = EH/Ev which reduces the systematic error in sin2θw, and incorporates electromagnetic and electroweak radiative corrections. In a renormalization scheme where sin2θw ≡ 1-m2W/m2Z, a value of sin2θw = 0.242+/-0.011+/-0.005 is obtained fixing ϱ = 1. If both sin2θw and ϱ are allowed to vary in a fit to our data, we measure ϱ = 0.991 +/- 0.025 +/- 0.009. Present address: IBM Thomas J. Watson Research Center, PO Box 218, Yorktown Heights, NY 10598, USA.

Deep sea tests of a prototype of the KM3NeT digital optical module

Energy Technology Data Exchange (ETDEWEB)

Adrian-Martinez, S.; Ardid, M.; Llorens Alvarez, C.D.; Saldana, M. [Universitat Politecnica de Valencia, Instituto de Investigacion para la Gestion Integrada de las Zonas Costeras, Gandia (Spain); Ageron, M.; Bertin, V.; Beurthey, S.; Billault, M.; Brunner, J.; Caillat, L.; Cosquer, A.; Coyle, P.; Curtil, C.; Destelle, J.J.; Dornic, D.; Gallo, F.; Henry, S.; Keller, P.; Lamare, P.; Royon, J.; Solazzo, M.; Tezier, D.; Theraube, S.; Yatkin, K. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Aharonian, F.; Drury, L. [DIAS, Dublin (Ireland); Aiello, S.; Giordano, V.; Leonora, E.; Randazzo, N.; Sipala, V. [INFN, Sezione di Catania, Catania (Italy); Albert, A.; Drouhin, D.; Racca, C. [GRPHE, Universite de Haute Alsace, IUT de Colmar, Colmar (France); Ameli, F.; De Bonis, G.; Nicolau, C.A.; Simeone, F. [INFN, Sezione di Roma, Rome (Italy); Anassontzis, E.G. [National and Kapodistrian University of Athens, Deparment of Physics, Athens (Greece); Anghinolfi, M.; Cereseto, R.; Hugon, C.; Kulikovskiy, V.; Musico, P.; Orzelli, A. [INFN, Sezione di Genova, Genoa (Italy); Anton, G.; Classen, L.; Eberl, T.; Enzenhoefer, A.; Gal, T.; Graf, K.; Heid, T.; Herold, B.; Hofestaedt, J.; Hoessl, J.; James, C.; Kalekin, O.; Kappes, A.; Katz, U.; Lahmann, R.; Reubelt, J.; Schnabel, J.; Seitz, T.; Stransky, D.; Tselengidou, M. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Erlangen Centre for Astroparticle Physics, Erlangen (Germany); Anvar, S.; Chateau, F.; Durand, D.; Le Provost, H.; Louis, F.; Moudden, Y.; Zonca, E. [CEA, Irfu/Sedi, Centre de Saclay, Gif-sur-Yvette (France); Asmundis, R. de; Deniskina, N.; Migliozzi, P.; Mollo, C. [INFN, Sezione di Napoli, Naples (Italy); Balasi, K.; Drakopoulou, E.; Markou, C.; Pikounis, K.; Siotis, I.; Stavropoulos, G.; Tzamariudaki, E. [Institute of Nuclear Physics, NCSR ' ' Demokritos' ' , Athens (Greece); Band, H.; Berbee, E.; Berkien, A.; Beveren, V. van; Boer Rookhuizen, H.; Bouwhuis, M.; Gajana, D.; Gebyehu, M.; Heijboer, A.; Heine, E.; Hoek, M. van der; Hogenbirk, J.; Jansweijer, P.; Kieft, G.; Kok, H.; Koopstra, J.; Korporaal, A.; Michael, T.; Mos, S.; Peek, H.; Schmelling, J.; Steijger, J.; Timmer, P.; Vermeulen, J.; Werneke, P.; Wiggers, L.; Zwart, A. [Nikhef, Amsterdam (Netherlands); Barbarino, G.; Barbato, F.; De Rosa, G.; Garufi, F.; Vivolo, D. [INFN, Sezione di Napoli, Naples (Italy); Universita ' Federico II' , Dipartimento di Fisica, Naples (Italy); Barbarito, E.; Ceres, A.; Circella, M.; Mongelli, M.; Sgura, I. [INFN, Sezione di Bari, Bari (Italy); Baret, B.; Baron, S.; Champion, C.; Colonges, S.; Creusot, A.; Galata, S.; Gracia Ruiz, R.; Kouchner, A.; Lindsey Clark, M.; Van Elewyck, V. [APC,Universite Paris Diderot, CNRS/IN2P3, CEA/IRFU Observatoire de Paris, Sorbonne Paris Cite, Paris (France); Belias, A.; Rapidis, P.A.; Trapierakis, H.I. [Institute of Nuclear Physics, NCSR ' ' Demokritos' ' , Athens (Greece); National Observatory of Athens, NESTOR Institute for Deep Sea Research, Technology, and Neutrino Astroparticle Physics, Pylos (Greece); Berg, A.M. van den; Dorosti-Hasankiadeh, Q.; Hevinga, M.A.; Kavatsyuk, O.; Loehner, H.; Wooning, R.H.L. van [KVI-CART, University of Groningen, Groningen (Netherlands); Beverini, N. [INFN, Sezione di Pisa, Pisa (Italy); Universita di Pisa, Dipertimento di Fisica, Pisa (Italy); Biagi, S.; Cecchini, S.; Fusco, L.A.; Margiotta, A.; Spurio, M. [INFN, Sezione di Bologna, Bologna (Italy); Universita di Bologna, Dipartimento di Fisica e Astronomia, Bologna (Italy); Bianucci, S.; Bouhadef, B.; Calamai, M.; Morganti, M.; Raffaelli, F.; Terreni, G. [Universita di Pisa, Dipertimento di Fisica, Pisa (Italy); Birbas, A.; Bourlis, G.; Christopoulou, B.; Gizani, N.; Leisos, A.; Lenis, D.; Tsirigotis, A.; Tzamarias, S. [Hellenic Open University, School of Science and Technology, Patras (Greece); Bormuth, R.; Jong, M. de; Samtleben, D.F.E. [Nikhef, Amsterdam (Netherlands); Leiden University, Leiden Institute of Physics, Leiden (Netherlands); Bouche, V.; Fermani, P.; Masullo, R.; Perrina, C. [INFN, Sezione di Roma, Rome (Italy); Universita di Roma La Sapienza, Dipartimento di Fisica, Rome (Italy); Bozza, C.; Grella, G. [Universita ' Federico II' , Dipartimento di Fisica, Naples (Italy); Universita di Salerno, Dipartimento di Fisica, Fisciano (Italy); Bruijn, R.; Koffeman, E.; Wolf, E. de [Nikhef, Amsterdam (Netherlands); University of Amsterdam, Institute of Physics, Amsterdam (Netherlands); Cacopardo, G.; Caruso, F.; Cocimano, R.; Coniglione, R.; Costa, M.; Cuttone, G.; D' Amato, C.; D' Amico, A.; Distefano, C.; Grasso, R.; Grmek, A.; Imbesi, M.; Larosa, G.; Lattuada, D.; Migneco, E.; Miraglia, A.; Musumeci, M.; Orlando, A.; Papaleo, R.; Pellegrino, C.; Pellegriti, M.G.; Piattelli, P. [INFN, Laboratori Nazionali del Sud, Catania (Italy); Collaboration: KM3NeT Collaboration; and others

2014-09-15

The first prototype of a photo-detection unit of the future KM3NeT neutrino telescope has been deployed in the deep waters of the Mediterranean Sea. This digital optical module has a novel design with a very large photocathode area segmented by the use of 31 three inch photomultiplier tubes. It has been integrated in the ANTARES detector for in-situ testing and validation. This paper reports on the first months of data taking and rate measurements. The analysis results highlight the capabilities of the new module design in terms of background suppression and signal recognition. The directionality of the optical module enables the recognition of multiple Cherenkov photons from the same {sup 40}K decay and the localisation of bioluminescent activity in the neighbourhood. The single unit can cleanly identify atmospheric muons and provide sensitivity to the muon arrival directions. (orig.)

Measurement of the atmospheric muon flux with a 4 GeV threshold in the ANTARES neutrino telescope

International Nuclear Information System (INIS)

Aguilar, J.A.; Al Samarai, I.; Albert, A.; Anghinolfi, M.; Anton, G.; Anvar, S.; Baret, B.; Donzaud, C.; Kouchner, A.; Moscoso, L.; Van Elewyck, V.; Basa, S.; Marcelin, M.; Mazure, A.; Tasca, L.; Carloganu, C.; Gay, P.; Charvis, Ph.; Deschamps, A.; Hello, Y.; Pillet, R.; Cottini, N.; Loucatos, S.; Moscoso, L.; Naumann, C.; Picq, C.; Schuller, J.P.; Stolarczyk, Th.; Vallage, B.; Vernin, P.

2010-01-01

A new method for the measurement of the muon flux in the deep-sea ANTARES neutrino telescope and its dependence on the depth is presented. The method is based oil the observation of coincidence signals in adjacent storeys of the detector. This yields an energy threshold of about 4 GeV. The main sources of optical background are the decay of 40 K and the bioluminescence in the sea water. The 40 K background is used to calibrate the efficiency of the photo-multiplier tubes. (authors)

Nematode assemblages in the deep-sea benthos of the Norwegian Sea

Science.gov (United States)

Jensen, Preben

1988-07-01

The deep-sea benthos of the Norwegian Sea contains 20-204 nematodes per 10 cm 2 down to 3 cm depth at seven stations sampled between 970 and 3294 m water depth. The majority of nematodes occur in the uppermost cm. Biomass varies from 3 to 73 μg C per 10 cm 2. Individual adult weight of the most dominant species differs by a factor of almost 1000, i.e. from 3-4 ng C to 3400 ng C; however, the majority of the nematodes is small-sized. Species diversity and evenness are high at all stations and each station harbours its specific fauna with little overlap between stations. Analysis of trophic group composition suggests that microbial feeding types (deposit and epistrate feeders) prevail in the deep-sea benthos; predators and scavengers are scarce. It is concluded that the nematode assemblage at each station consists of a mosaic of many microhabitats. The small nematode body weight probably results from limited food supply and/or poor food quality.

Deep-sea environment and biodiversity of the West African Equatorial margin

OpenAIRE

Sibuet, Myriam; Vangriesheim, Annick

2009-01-01

The long-term BIOZAIRE multidisciplinary deep-sea environmental program on the West Equatorial African margin organized in partnership between Ifremer and TOTAL aimed at characterizing the benthic community structure in relation with physical and chemical processes in a region of oil and gas interest. The morphology of the deep Congo submarine channel and the sedimentological structures of the deep-sea fan were established during the geological ZAIANGO project and helped to select study sites...

Diversity and adaptations of deep-sea microorganisms

Digital Repository Service at National Institute of Oceanography (India)

Raghukumar, C.

-tolerant enzymes, natural products of potential use in human health management and environmental bioremediation using solvent-tolerant microorganisms are some of the potential biotechnological applications of these deep-sea microbes....

Worldwide Analysis of Sedimentary DNA Reveals Major Gaps in Taxonomic Knowledge of Deep-Sea Benthos

DEFF Research Database (Denmark)

Sinniger, Frédéric; Pawlowski, Jan; Harii, Saki

2016-01-01

in 39 deep-sea sediment samples from bathyal and abyssal depths worldwide. The eDNA dataset was dominated by meiobenthic taxa and we identified all animal phyla commonly found in the deep-sea benthos; yet, the diversity within these phyla remains largely unknown. The large numbers of taxonomically...... for pure and applied deep-sea environmental research but also emphasizes the necessity to integrate such new approaches with traditional morphology-based examination of deep-sea organisms....

Generation of auroral kilometric radiation

International Nuclear Information System (INIS)

Green, J.L.

1979-01-01

Simultaneous observations between the Hawkeye spacecraft in the AKR emission cone and the low altitude polar orbiting spacecraft Triad and AE-D reveal that auroral kilometric radiation (AKR) is correlated with a variety of auroral particle precipitation in the evening to midnight local time sector. It is found that as the AKR intensity increases so does the integrated current sheet intensity of auroral zone field aligned currents observed by Triad of 257 simultaneous observations. Statistically, the linear correlation coefficient between the log of the AKR power flux and the log of the current sheet intensity is 0.57. Auroral kilometric radiation observations from Hawkeye during low altitude (2.0 to 2.5 R/sub E/) auroral zone passes reveal that intense AKR has a low frequency cutoff near the local electron gyrofrequency (f/sub g/ - ) with maximum electric field strengths as large as 12 mV/m. The large electric fields observed near f/sub g/ - are consistent with high altitude observations of AKR using a simple 1/R 2 scaling indicating that the kilometric radiation in or near the average source region is almost completely electromagnetic. The results presented in this study indicate that kilometric radiation is generated by inverted-V electron distribution functions in a direct coupling mechanism between particle energy and R-X mode electromagnetic waves in the region of the auroral zone where f/sub g/ - >> f/sub p/ -

Photon Detection System Designs for the Deep Underground Neutrino Experiment

Energy Technology Data Exchange (ETDEWEB)

Whittington, Denver [Indiana U.

2015-11-19

The Deep Underground Neutrino Experiment (DUNE) will be a premier facility for exploring long-standing questions about the boundaries of the standard model. Acting in concert with the liquid argon time projection chambers underpinning the far detector design, the DUNE photon detection system will capture ultraviolet scintillation light in order to provide valuable timing information for event reconstruction. To maximize the active area while maintaining a small photocathode coverage, the experiment will utilize a design based on plastic light guides coated with a wavelength-shifting compound, along with silicon photomultipliers, to collect and record scintillation light from liquid argon. This report presents recent preliminary performance measurements of this baseline design and several alternative designs which promise significant improvements in sensitivity to low-energy interactions.

Studies of the reproductive biology of deep-sea megabenthos

International Nuclear Information System (INIS)

Tyler, P.A.

1987-07-01

The final report describes the general biology and ecology of the 15 holothurians, 3 asteroids, 2 zoanthids and 1 crustacea species studied in Reports I-XIII, the sampling methods used and the station data. A summary of the histological, histochemical and biochemical results for the species examined is given. The data suggest that the reproductive processes in the deep-sea species examined are highly unlikely to be part of a pathway for the transfer of radionuclides from the deep-sea back to man. (author)

Sterile neutrinos in the early universe

Energy Technology Data Exchange (ETDEWEB)

Malaney, R.A. (Lawrence Livermore National Lab., CA (USA)); Fuller, G.M. (California Univ., San Diego, La Jolla, CA (USA). Dept. of Physics)

1990-11-14

We discuss the role played by right-handed sterile neutrinos in the early universe. We show how well known {sup 4}He constraint on the number of relativistic degrees of freedom at early times limits the equilibration of the right handed neutrino sea with the background plasma. We discuss how this allows interesting constraints to be placed on neutrino properties. In particular, a new limit on the Dirac mass of the neutrino is presented. 12 refs.

The National Deep-Sea Coral and Sponge Database: A Comprehensive Resource for United States Deep-Sea Coral and Sponge Records

Science.gov (United States)

Dornback, M.; Hourigan, T.; Etnoyer, P.; McGuinn, R.; Cross, S. L.

2014-12-01

Research on deep-sea corals has expanded rapidly over the last two decades, as scientists began to realize their value as long-lived structural components of high biodiversity habitats and archives of environmental information. The NOAA Deep Sea Coral Research and Technology Program's National Database for Deep-Sea Corals and Sponges is a comprehensive resource for georeferenced data on these organisms in U.S. waters. The National Database currently includes more than 220,000 deep-sea coral records representing approximately 880 unique species. Database records from museum archives, commercial and scientific bycatch, and from journal publications provide baseline information with relatively coarse spatial resolution dating back as far as 1842. These data are complemented by modern, in-situ submersible observations with high spatial resolution, from surveys conducted by NOAA and NOAA partners. Management of high volumes of modern high-resolution observational data can be challenging. NOAA is working with our data partners to incorporate this occurrence data into the National Database, along with images and associated information related to geoposition, time, biology, taxonomy, environment, provenance, and accuracy. NOAA is also working to link associated datasets collected by our program's research, to properly archive them to the NOAA National Data Centers, to build a robust metadata record, and to establish a standard protocol to simplify the process. Access to the National Database is provided through an online mapping portal. The map displays point based records from the database. Records can be refined by taxon, region, time, and depth. The queries and extent used to view the map can also be used to download subsets of the database. The database, map, and website is already in use by NOAA, regional fishery management councils, and regional ocean planning bodies, but we envision it as a model that can expand to accommodate data on a global scale.

How deep-sea wood falls sustain chemosynthetic life.

Directory of Open Access Journals (Sweden)

Christina Bienhold

Full Text Available Large organic food falls to the deep sea--such as whale carcasses and wood logs--are known to serve as stepping stones for the dispersal of highly adapted chemosynthetic organisms inhabiting hot vents and cold seeps. Here we investigated the biogeochemical and microbiological processes leading to the development of sulfidic niches by deploying wood colonization experiments at a depth of 1690 m in the Eastern Mediterranean for one year. Wood-boring bivalves of the genus Xylophaga played a key role in the degradation of the wood logs, facilitating the development of anoxic zones and anaerobic microbial processes such as sulfate reduction. Fauna and bacteria associated with the wood included types reported from other deep-sea habitats including chemosynthetic ecosystems, confirming the potential role of large organic food falls as biodiversity hot spots and stepping stones for vent and seep communities. Specific bacterial communities developed on and around the wood falls within one year and were distinct from freshly submerged wood and background sediments. These included sulfate-reducing and cellulolytic bacterial taxa, which are likely to play an important role in the utilization of wood by chemosynthetic life and other deep-sea animals.

How Deep-Sea Wood Falls Sustain Chemosynthetic Life

Science.gov (United States)

Bienhold, Christina; Pop Ristova, Petra; Wenzhöfer, Frank; Dittmar, Thorsten; Boetius, Antje

2013-01-01

Large organic food falls to the deep sea – such as whale carcasses and wood logs – are known to serve as stepping stones for the dispersal of highly adapted chemosynthetic organisms inhabiting hot vents and cold seeps. Here we investigated the biogeochemical and microbiological processes leading to the development of sulfidic niches by deploying wood colonization experiments at a depth of 1690 m in the Eastern Mediterranean for one year. Wood-boring bivalves of the genus Xylophaga played a key role in the degradation of the wood logs, facilitating the development of anoxic zones and anaerobic microbial processes such as sulfate reduction. Fauna and bacteria associated with the wood included types reported from other deep-sea habitats including chemosynthetic ecosystems, confirming the potential role of large organic food falls as biodiversity hot spots and stepping stones for vent and seep communities. Specific bacterial communities developed on and around the wood falls within one year and were distinct from freshly submerged wood and background sediments. These included sulfate-reducing and cellulolytic bacterial taxa, which are likely to play an important role in the utilization of wood by chemosynthetic life and other deep-sea animals. PMID:23301092

Advances in deep-sea biology: biodiversity, ecosystem functioning and conservation. An introduction and overview

Science.gov (United States)

Cunha, Marina R.; Hilário, Ana; Santos, Ricardo S.

2017-03-01

Once considered as monotonous and devoid of life, the deep sea was revealed during the last century as an environment with a plethora of life forms and extremely high species richness (Rex and Etter, 2010). Underwater vehicle developments allowed direct observations of the deep, disclosing unique habitats and diverse seascapes, and other technological advances enabled manipulative experimentation and unprecedented prospects to pursue novel research topics (Levin and Sibuet, 2012; Danovaro et al., 2014). Alongside, the growing human population greatly increased the pressure on deep-sea ecosystems and the services they provide (Ramirez-Llodra et al., 2011; Thurber et al., 2014; Levin et al., 2016). Societal changes further intensified worldwide competition for natural resources, extending the present footprint of impacts over most of the global ocean (Halpern et al., 2008). In this socio-economic context, and in tandem with cutting edge technological advances and an unclear legal framework to regulate access to natural resources (Boyes and Elliott, 2014), the deep sea has emerged as a new opportunity for industrial exploitation and novel economic activities. The expanding use of the deep sea prompted a rapid reply from deep-sea scientists that recommended "a move from a frontier mentality of exploitation and single-sector management to a precautionary system that balances use of living marine resources, energy, and minerals from the deep ocean with maintenance of a productive and healthy marine environment, while improving knowledge and collaboration" and proposed "three directions to advance deep-ocean stewardship: i) protection and mitigation, ii) research, and iii) collaborative governance" (Mengerink et al., 2014). The European Marine Board position paper 22 (Rogers et al., 2015) further examined the key societal and environmental drivers confronting the deep sea and the role of deep-sea research to deliver future knowledge needs for science and society; a clear

Invertebrate population genetics across Earth's largest habitat: The deep-sea floor.

Science.gov (United States)

Taylor, M L; Roterman, C N

2017-10-01

Despite the deep sea being the largest habitat on Earth, there are just 77 population genetic studies of invertebrates (115 species) inhabiting non-chemosynthetic ecosystems on the deep-sea floor (below 200 m depth). We review and synthesize the results of these papers. Studies reveal levels of genetic diversity comparable to shallow-water species. Generally, populations at similar depths were well connected over 100s-1,000s km, but studies that sampled across depth ranges reveal population structure at much smaller scales (100s-1,000s m) consistent with isolation by adaptation across environmental gradients, or the existence of physical barriers to connectivity with depth. Few studies were ocean-wide (under 4%), and 48% were Atlantic-focused. There is strong emphasis on megafauna and commercial species with research into meiofauna, "ecosystem engineers" and other ecologically important species lacking. Only nine papers account for ~50% of the planet's surface (depths below 3,500 m). Just two species were studied below 5,000 m, a quarter of Earth's seafloor. Most studies used single-locus mitochondrial genes revealing a common pattern of non-neutrality, consistent with demographic instability or selective sweeps; similar to deep-sea hydrothermal vent fauna. The absence of a clear difference between vent and non-vent could signify that demographic instability is common in the deep sea, or that selective sweeps render single-locus mitochondrial studies demographically uninformative. The number of population genetics studies to date is miniscule in relation to the size of the deep sea. The paucity of studies constrains meta-analyses where broad inferences about deep-sea ecology could be made. © 2017 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

Deep Coherent Vortices and Their Sea Surface Expressions

Science.gov (United States)

Ienna, Federico; Bashmachnikov, Igor; Dias, Joaquim; Peliz, Alvaro

2017-04-01

Mediterranean Water eddies, known as Meddies, are an important dynamic process occurring at depths of 1000-meters in the Northeast Atlantic Ocean. Meddies occur as a direct result of the Mediterranean Outflow exiting through the Gibraltar Strait, and represent a prevalent mechanism that can be found extensively throughout the ocean. Moreover, Meddy cores are known to produce measurable expressions at the sea surface in the form of rotating coherent vortices, not only affecting the sea surface from beneath, but also allowing for the possibility to remotely study these deep phenomena through data gathered at the sea surface. While many past studies have focused on the properties of Meddy cores, only a handful of studies focus on the physical characteristics and behavior of the surface expressions produced. Are Meddy surface expressions different from other like vortices that dominate the physical ocean surface? What are the relationships between deep and surface mechanisms, and do any feedbacks exist? To shed light on these questions, we investigate the relationship between Meddies and their sea-surface expressions through observations using in-situ float and drifter profiles and satellite altimetry. A total of 782 Meddy cores were examined in the Northeast Atlantic using temperature and salinity data obtained by CTD and Argo during the Mecanismos de transporte e de dispersão da Água Mediterrânica no Atlântico Nordeste (MEDTRANS) project, and their corresponding sea-level expressions were geo-temporally matched in satellite altimetry data. We report several statistical properties of the sea-surface expressions of Meddies, including their mean diameter and vertical magnitude, and compare the properties of their surface features to the underlying Meddy cores. We investigate how the deep core affects the surface, and whether surface expressions may in return yield information about the underlying cores. Additionally, we examine the variability of the surface

An interactive end-user software application for a deep-sea photographic database

Digital Repository Service at National Institute of Oceanography (India)

Jaisankar, S.; Sharma, R.

. The software is the first of its kind in deep-sea applications and it also attempts to educate the user about deep-sea photography. The application software is developed by modifying established routines and by creating new routines to save the retrieved...

ProtoDUNE-DP---PROTOtype for the Deep Underground Neutrino Experiment - Dual Phase detector (Electrostatic Simulations and Performance Studies)

CERN Document Server

Chiu, Pin-Jung

In search of answers to the biggest missing puzzle in the field of neutrino physics, large- scale Liquid Argon Time Projection Chambers (LAr-TPCs) have been postulated to be the most attractive instruments for next generation neutrino observations. A state-of-the- art experiment, the Deep Underground Neutrino Experiment (DUNE), which will utilize this LAr-TPC technology for the studies of neutrino science and proton decay, is currently in the stage of design and prototyping. This thesis reports on the behavior studies of a 6 × 6 × 6 m^3 prototype, ProtoDUNE, in the context of DUNE from the electrostatic’s point of view. Electrostatic simulations had been performed on the whole detector in order to verify the uniformity of the electric field, and to assure that all local electric fields within the detector are below a certain value to avoid any electrical breakdown phenomena. Additionally, to characterize the performance of the 2D anode used for charge readout in the experiment, some simulations and measur...

Microbial ecology of deep-sea hypersaline anoxic basins

KAUST Repository

Merlino, Giuseppe

2018-05-09

Deep hypersaline anoxic basins (DHABs) are unique water bodies occurring within fractures at the bottom of the sea, where the dissolution of anciently buried evaporites created dense anoxic brines that are separated by a chemocline/pycnocline from the overlying oxygenated deep-seawater column. DHABs have been described in the Gulf of Mexico, the Mediterranean Sea, the Black Sea and the Red Sea. They are characterized by prolonged historical separation of the brines from the upper water column due to lack of mixing and by extreme conditions of salinity, anoxia, and relatively high hydrostatic pressure and temperatures. Due to these combined selection factors, unique microbial assemblages thrive in these polyextreme ecosystems. The topological localization of the different taxa in the brine-seawater transition zone coupled with the metabolic interactions and niche adaptations determine the metabolic functioning and biogeochemistry of DHABs. In particular, inherent metabolic strategies accompanied by genetic adaptations have provided insights on how prokaryotic communities can adapt to salt-saturated condition. Here, we review the current knowledge on the diversity, genomics, metabolisms and ecology of prokaryotes in DHABs.

Measurement of the atmospheric muon flux with a 4 GeV threshold in the ANTARES neutrino telescope

Energy Technology Data Exchange (ETDEWEB)

Aguilar, J.A. [IFIC - Instituto de Fisica Corpuscular, Edificios Investigacion de Paterna, CSIC - Universitat de Valencia, Apdo. de Correos 22085, 46071 Valencia (Spain); Al Samarai, I. [CPPM - Centre de Physique des Particules de Marseille, CNRS/IN2P3 et Universite de la Mediterranee, 163 Avenue de Luminy, Case 902, 13288 Marseille Cedex 9 (FR); Albert, A. [GRPHE - Institut Universitaire de Technologie de Colmar, 34 Rue du Grillenbreit, BP 50568, 68008 Colmar (FR); Anghinolfi, M. [INFN - Sezione di Genova, Via Dodecaneso 33, 16146 Genova (Italy); Anton, G. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Erlangen Centre for Astroparticle Physics, Erwin-Rommel-Str. 1, D-91058 Erlangen (Germany); Anvar, S. [Direction des Sciences de la Matiere - Institut de Recherche sur les lois Fondamentales de l' Univers - Service d' Electronique des Detecteurs et d' Informatique, CEA Saclay, 91191 Gif-sur-Yvette Cedex (FR); Baret, B.; Donzaud, C.; Kouchner, A.; Moscoso, L.; Van Elewyck, V. [APC - Laboratoire AstroParticule et Cosmologie, UMR 7164, CNRS, Universite Paris 7 Diderot, CEA, Observatoire de Paris, 10, Rue Alice Domon et Leonie Duquet, 75205 Paris Cedex 13 (FR); Basa, S.; Marcelin, M.; Mazure, A.; Tasca, L. [Laboratoire d' Astrophysique de Marseille, Pole de l' Etoile Site de Chateau-Gombert, Marseille (FR); Carloganu, C.; Gay, P. [Lab. de Physique Corpusculaire, IN2P3-CNRS, Universite Blaise Pascal, Clermont-Ferrand (FR); Charvis, Ph.; Deschamps, A.; Hello, Y.; Pillet, R. [Geoazur - Universite de Nice Sophia-Antipolis, CNRS/INSU, IRD, Observatoire de la Cote d' Azur and Universite Pierre et Marie Curie, BP 48, F-06235 Villefranche-sur-mer (FR); Cottini, N.; Loucatos, S.; Moscoso, L.; Naumann, C.; Picq, C.; Schuller, J.P.; Stolarczyk, Th.; Vallage, B.; Vernin, P. [Direction des Sciences de la Matiere - Institut de Recherche sur les lois Fondamentales de l' Univers - Service de Physique des Particules, CEA Saclay, 91191 Gif-sur-Yvette (FR)

2010-07-01

A new method for the measurement of the muon flux in the deep-sea ANTARES neutrino telescope and its dependence on the depth is presented. The method is based oil the observation of coincidence signals in adjacent storeys of the detector. This yields an energy threshold of about 4 GeV. The main sources of optical background are the decay of {sup 40}K and the bioluminescence in the sea water. The {sup 40}K background is used to calibrate the efficiency of the photo-multiplier tubes. (authors)

A Nine-Year Hunt for Neutrinos

Science.gov (United States)

Kohler, Susanna

2018-02-01

.Observatories on the HuntNeutrino observatories are often built to take advantage of pre-existing deep bodies of ice or water for their detectors. One of the most well-known neutrino observatories is IceCube, an array of detectors located far beneath the Antarctic ice. A few years ago, IceCube announced the observation of an excess of events over the expected atmospheric background the first detection of a diffuse flux of cosmic neutrinos. The next step:confirmation from another observatory.ANTARES detections across different energy bins, for both track-like (top) and shower-like (bottom) events. Plot includes data (black), model for atmospheric events (blue), and two different models for cosmic events (red). Above an energy cutoff of 20 TeV (grey line), nine excess neutrinos are detected relative to the atmospheric model. [Albert et al. 2018]Enter ANTARES, short for Astronomy with a Neutrino Telescope and Abyss Environmental Research. Completed in 2008, this neutrino telescope was built 1.5 miles beneath the surface of the Mediterranean Sea. Now the collaboration is presenting the results of their nine-year search for a diffuse cosmic neutrino flux.A Mild ExcessThe outcome? Success! sort of.The very nature of neutrinos elusiveness means that we have to draw conclusions with very small numbers of detections. Over nine years, ANTARES detected a total of 33 events above an energy cutoff of 20 TeV, whereas models predict it should have seen only 24 such events due to atmospheric particles. This detection of nine extra neutrinos may sound insubstantial but statistically, it allows the team to reject the hypothesis that there is no diffuse cosmic flux at an 85% confidence level.The mild excess of neutrinos detected by ANTARES is by no means a smoking gun, but the properties of this cosmic neutrino flux are consistent with those detected by IceCube, which is a very promising outcome. At the moment, it would seem that a diffuse flux of cosmic neutrinos is present and the next generation

De novo transcriptome assembly and positive selection analysis of an individual deep-sea fish.

Science.gov (United States)

Lan, Yi; Sun, Jin; Xu, Ting; Chen, Chong; Tian, Renmao; Qiu, Jian-Wen; Qian, Pei-Yuan

2018-05-24

High hydrostatic pressure and low temperatures make the deep sea a harsh environment for life forms. Actin organization and microtubules assembly, which are essential for intracellular transport and cell motility, can be disrupted by high hydrostatic pressure. High hydrostatic pressure can also damage DNA. Nucleic acids exposed to low temperatures can form secondary structures that hinder genetic information processing. To study how deep-sea creatures adapt to such a hostile environment, one of the most straightforward ways is to sequence and compare their genes with those of their shallow-water relatives. We captured an individual of the fish species Aldrovandia affinis, which is a typical deep-sea inhabitant, from the Okinawa Trough at a depth of 1550 m using a remotely operated vehicle (ROV). We sequenced its transcriptome and analyzed its molecular adaptation. We obtained 27,633 protein coding sequences using an Illumina platform and compared them with those of several shallow-water fish species. Analysis of 4918 single-copy orthologs identified 138 positively selected genes in A. affinis, including genes involved in microtubule regulation. Particularly, functional domains related to cold shock as well as DNA repair are exposed to positive selection pressure in both deep-sea fish and hadal amphipod. Overall, we have identified a set of positively selected genes related to cytoskeleton structures, DNA repair and genetic information processing, which shed light on molecular adaptation to the deep sea. These results suggest that amino acid substitutions of these positively selected genes may contribute crucially to the adaptation of deep-sea animals. Additionally, we provide a high-quality transcriptome of a deep-sea fish for future deep-sea studies.

Species-energy relationship in the deep sea: A test using the Quaternary fossil record

Science.gov (United States)

Hunt, G.; Cronin, T. M.; Roy, K.

2005-01-01

Little is known about the processes regulating species richness in deep-sea communities. Here we take advantage of natural experiments involving climate change to test whether predictions of the species-energy hypothesis hold in the deep sea. In addition, we test for the relationship between temperature and species richness predicted by a recent model based on biochemical kinetics of metabolism. Using the deep-sea fossil record of benthic foraminifera and statistical meta-analyses of temperature-richness and productivity-richness relationships in 10 deep-sea cores, we show that temperature but not productivity is a significant predictor of species richness over the past c. 130 000 years. Our results not only show that the temperature-richness relationship in the deep-sea is remarkably similar to that found in terrestrial and shallow marine habitats, but also that species richness tracks temperature change over geological time, at least on scales of c. 100 000 years. Thus, predicting biotic response to global climate change in the deep sea would require better understanding of how temperature regulates the occurrences and geographical ranges of species. ??2005 Blackwell Publishing Ltd/CNRS.

Deepwater Program: Lophelia II, continuing ecological research on deep-sea corals and deep-reef habitats in the Gulf of Mexico

Science.gov (United States)

Demopoulos, Amanda W.J.; Ross, Steve W.; Kellogg, Christina A.; Morrison, Cheryl L.; Nizinski, Martha S.; Prouty, Nancy G.; Bourque, Jill R.; Galkiewicz, Julie P.; Gray, Michael A.; Springmann, Marcus J.; Coykendall, D. Katharine; Miller, Andrew; Rhode, Mike; Quattrini, Andrea; Ames, Cheryl L.; Brooke, Sandra D.; McClain Counts, Jennifer; Roark, E. Brendan; Buster, Noreen A.; Phillips, Ryan M.; Frometa, Janessy

2017-12-11

The deep sea is a rich environment composed of diverse habitat types. While deep-sea coral habitats have been discovered within each ocean basin, knowledge about the ecology of these habitats and associated inhabitants continues to grow. This report presents information and results from the Lophelia II project that examined deep-sea coral habitats in the Gulf of Mexico. The Lophelia II project focused on Lophelia pertusa habitats along the continental slope, at depths ranging from 300 to 1,000 meters. The chapters are authored by several scientists from the U.S. Geological Survey, National Oceanic and Atmospheric Administration, University of North Carolina Wilmington, and Florida State University who examined the community ecology (from microbes to fishes), deep-sea coral age, growth, and reproduction, and population connectivity of deep-sea corals and inhabitants. Data from these studies are presented in the chapters and appendixes of the report as well as in journal publications. This study was conducted by the Ecosystems Mission Area of the U.S. Geological Survey to meet information needs identified by the Bureau of Ocean Energy Management.

Multibody neutrino exchange in a neutron star neutrino sea and border effects

CERN Document Server

Abada, A; Rodríguez-Quintero, J; Abada, As

1998-01-01

The interaction due to the exchange of massless neutrinos between neutrons is a long-range force. Border effects on this multibody exchange inside a dense core are studied and computed analytically in 1 + 1 dimensions. We demonstrate in this work that a proper treatment of the star's border effect automatically incorporates the condensate contribution as a consequence of the appropriate boundary conditions for the neutrino Feynman propagator inside the star. The total multibody exchange contribution is infrared-safe and vanishes exactly in 1 + 1 dimensions. The general conclusion of this work is that the border effect does not modify the result that neutrino exchange is infrared-safe. This toy model prepares the ground and gives the tools for the study of the realistic 3 + 1 star.

Genetic diversity of archaea in deep-sea hydrothermal vent environments.

OpenAIRE

Takai, K; Horikoshi, K

1999-01-01

Molecular phylogenetic analysis of naturally occurring archaeal communities in deep-sea hydrothermal vent environments was carried out by PCR-mediated small subunit rRNA gene (SSU rDNA) sequencing. As determined through partial sequencing of rDNA clones amplified with archaea-specific primers, the archaeal populations in deep-sea hydrothermal vent environments showed a great genetic diversity, and most members of these populations appeared to be uncultivated and unidentified organisms. In the...

A review on deep-sea fungi: Occurrence, diversity and adaptions

Digital Repository Service at National Institute of Oceanography (India)

Raghukumar, C.; Damare, S.R.; Singh, P.

soil. In contrast to land, however, most studies on deep-sea sediments have focused exclusively on bacteria and have demonstrated their intense metabolic activities therein (Turley and Dixon 2002). The fungi and their role in the deep-sea sediments... polymerization and form brown-coloured products, constituting humus (Tisdall and Oades 1982). The humic material combines with soil particles to form microaggregates. Fungal hyphae further act as binding agents to form macroaggregates by trapping fine particles...

Meso- and small-scale vertical motions in the deep Western Mediterranean

Energy Technology Data Exchange (ETDEWEB)

Haren, Hans van, E-mail: hans.van.haren@nioz.n [Royal Netherlands Institute for Sea Research (NIOZ), P.O. Box 59, 1790 AB Den Burg (Netherlands)

2011-01-21

Acoustic reflections on particles larger than a few mm are compared with optical background data of bioluminescence at the ANTARES neutrino telescope site in the deep North-western Mediterranean Sea. Periodic increases of these data are associated with increases in horizontal and downward vertical currents. The observations provide unique knowledge of some oceanographic processes in the Mediterranean. Several periodicities are distinguished: seasonal, with large increase during spring, 20-day, which is associated with a meandering continental boundary current, 1-17.6 h, evidencing deep internal waves.

The history of neutrinos, 1930–1985. What have we learned about neutrinos? What have we learned using neutrinos?

International Nuclear Information System (INIS)

Steinberger, J.

2012-01-01

An attempt to remember some of the main events which highlight the evolution of our knowledge of the neutrinos and their properties, the “families” of particles, a few of the very interesting persons who contributed to this progress, as well as the contribution of neutrino beam experiments to the validation of the electro-weak and quantum-chromo-dynamic theories, and the structure of the nucleon. - Highlights: ► Early history: continuity of β-spectrum, Pauli letter, universal Fermi interaction. ► Neutrino beams and the discovery of the muon neutrino. ► Gargamelle, the discovery of the neutral current and the verification of the quark–gluon nature of the parton. ► Deep inelastic scattering at higher energies: scaling, quantitative verification of QCD, structure functions.

Deep-sea genetic resources: New frontiers for science and stewardship in areas beyond national jurisdiction

Science.gov (United States)

Harden-Davies, Harriet

2017-03-01

The deep-sea is a large source of marine genetic resources (MGR), which have many potential uses and are a growing area of research. Much of the deep-sea lies in areas beyond national jurisdiction (ABNJ), including 65% of the global ocean. MGR in ABNJ occupy a significant gap in the international legal framework. Access and benefit sharing of MGR is a key issue in the development of a new international legally-binding instrument under the United Nations Convention on the Law of the Sea (UNCLOS) for the conservation and sustainable use of marine biological diversity in ABNJ. This paper examines how this is relevant to deep-sea scientific research and identifies emerging challenges and opportunities. There is no internationally agreed definition of MGR, however, deep-sea genetic resources could incorporate any biological material including genes, proteins and natural products. Deep-sea scientific research is the key actor accessing MGR in ABNJ and sharing benefits such as data, samples and knowledge. UNCLOS provides the international legal framework for marine scientific research, international science cooperation, capacity building and marine technology transfer. Enhanced implementation could support access and benefit sharing of MGR in ABNJ. Deep-sea scientific researchers could play an important role in informing practical new governance solutions for access and benefit sharing of MGR that promote scientific research in ABNJ and support deep-sea stewardship. Advancing knowledge of deep-sea biodiversity in ABNJ, enhancing open-access to data and samples, standardisation and international marine science cooperation are significant potential opportunity areas.

Gulf of Mexico Deep-Sea Coral Ecosystem Studies, 2008-2011

Science.gov (United States)

Kellogg, Christina A.

2009-01-01

Most people are familiar with tropical coral reefs, located in warm, well-illuminated, shallow waters. However, corals also exist hundreds and even thousands of meters below the ocean surface, where it is cold and completely dark. These deep-sea corals, also known as cold-water corals, have become a topic of interest due to conservation concerns over the impacts of trawling, exploration for oil and gas, and climate change. Although the existence of these corals has been known since the 1800s, our understanding of their distribution, ecology, and biology is limited due to the technical difficulties of conducting deep-sea research. DISCOVRE (DIversity, Systematics, and COnnectivity of Vulnerable Reef Ecosystems) is a new U.S. Geological Survey (USGS) program focused on deep-water coral ecosystems in the Gulf of Mexico. This integrated, multidisciplinary, international effort investigates a variety of topics related to unique and fragile deep-sea coral ecosystems from the microscopic level to the ecosystem level, including components of microbiology, population genetics, paleoecology, food webs, taxonomy, community ecology, physical oceanography, and mapping.

Deep-UV Emitters and Detectors Based on Lattice-Matched Cubic Oxide Semiconductors (4.2 Optoelectronics)

Science.gov (United States)

2015-05-14

calculated   by   dividing   photo-­‐‑ generated  current  by  the  optical  power  spectrum  of  the   lamp .    A   UV ...the optimized parameters for growth. Efforts led to significant increases in solar?blind detector responsivity (up to 0.1 A/W) with sub-­ nanoamp...Aug-2014 Approved for Public Release; Distribution Unlimited Final Report: Deep- UV Emitters and Detectors Based on Lattice- Matched Cubic Oxide

Exploring fungal diversity in deep-sea sediments from Okinawa Trough using high-throughput Illumina sequencing

Science.gov (United States)

Zhang, Xiao-Yong; Wang, Guang-Hua; Xu, Xin-Ya; Nong, Xu-Hua; Wang, Jie; Amin, Muhammad; Qi, Shu-Hua

2016-10-01

The present study investigated the fungal diversity in four different deep-sea sediments from Okinawa Trough using high-throughput Illumina sequencing of the nuclear ribosomal internal transcribed spacer-1 (ITS1). A total of 40,297 fungal ITS1 sequences clustered into 420 operational taxonomic units (OTUs) with 97% sequence similarity and 170 taxa were recovered from these sediments. Most ITS1 sequences (78%) belonged to the phylum Ascomycota, followed by Basidiomycota (17.3%), Zygomycota (1.5%) and Chytridiomycota (0.8%), and a small proportion (2.4%) belonged to unassigned fungal phyla. Compared with previous studies on fungal diversity of sediments from deep-sea environments by culture-dependent approach and clone library analysis, the present result suggested that Illumina sequencing had been dramatically accelerating the discovery of fungal community of deep-sea sediments. Furthermore, our results revealed that Sordariomycetes was the most diverse and abundant fungal class in this study, challenging the traditional view that the diversity of Sordariomycetes phylotypes was low in the deep-sea environments. In addition, more than 12 taxa accounted for 21.5% sequences were found to be rarely reported as deep-sea fungi, suggesting the deep-sea sediments from Okinawa Trough harbored a plethora of different fungal communities compared with other deep-sea environments. To our knowledge, this study is the first exploration of the fungal diversity in deep-sea sediments from Okinawa Trough using high-throughput Illumina sequencing.

Ventilation of the deep Greenland and Norwegian seas: evidence from krypton-85, tritium, carbon-14 and argon-39

International Nuclear Information System (INIS)

Smethie, W.M. Jr.; Ostlund, H.G.; Loosli, H.H.

1986-01-01

On leg 5 of the TTO expedition, the distributions of 85 Kr, tritium, 14 C, 39 Ar, temperature, salinity, oxygen, carbon dioxide and nutrients were measured in the Greenland and Norwegian seas. These observations support previous observations that Greenland Sea Deep Water is formed by a deep convective process within the Greenland gyre. They also support AAGAARD et al.'s (1985, Journal of Geophysical Research, 90, 4833-4846) new hypothesis that Norwegian Sea Deep Water forms from a mixture of Greenland Sea Deep Water and Eurasian Basin Deep Water. Volume transports estimated from the distributions of 85 Kr, tritium, 14 C and 39 Ar range from 0.53 to 0.74 Sv for exchange between the surface and deep Greenland Sea and from 0.9 to 1.47 Sv for exchange between the deep Greenland and deep Norwegian Seas. The residence time of water and the deep Greenland Sea with respect to exchange with surface water ranges from 24 to 34 years reported by PETERSON and ROOTH (1976, Deep-Sea Research, 23, 273-283) and 35-42 years reported by BULLISTER and WEISS (1983, Science, 221, 265-268). The residence time of water in the deep Norwegian Sea with respect to exchange with the deep Greenland Sea ranges from 19 to 30 years compared to 97-107 years reported by PETERSON and ROOTH (1976) and 10-28 years reported by BULLISTER and WEISS (1983). The oxygen consumption rate was estimated to be at most 1.04 μM kg -1 y -1 for the deep Greenland Sea and to be between 0.47 and 0.79 μM kg -1 y -1 for the deep Norwegian Sea. (author)

Testing deep-sea biodiversity paradigms on abyssal nematode genera and Acantholaimus species

Science.gov (United States)

Lins, Lidia; da Silva, Maria Cristina; Neres, Patrícia; Esteves, André Morgado; Vanreusel, Ann

2018-02-01

Biodiversity patterns in the deep sea have been extensively studied in the last decades. In this study, we investigated whether reputable concepts in deep-sea ecology also explain diversity and distribution patterns of nematode genera and species in the abyss. Among them, three paradigms were tackled: (1) the deep sea is a highly diverse environment at a local scale, while on a regional and even larger geographical scale, species and genus turnover is limited; (2) the biodiversity of deep-sea nematode communities changes with the nature and amount of organic matter input from the surface; and (3) patch-mosaic dynamics of the deep-sea environment drive local diversity. To test these hypotheses, diversity and density of nematode assemblages and of species of the genus Acantholaimus were studied along two abyssal E-W transects. These two transects were situated in the Southern Ocean ( 50°S) and the North Atlantic ( 10°N). Four different hierarchical scales were used to compare biodiversity: at the scale of cores, between stations from the same region, and between regions. Results revealed that the deep sea harbours a high diversity at a local scale (alpha diversity), but that turnover can be shaped by different environmental drivers. Therefore, these results question the second part of the paradigm about limited species turnover in the deep sea. Higher surface primary productivity was correlated with greater nematode densities, whereas diversity responses to the augmentation of surface productivity showed no trend. Areas subjected to a constant and low food input revealed similar nematode communities to other oligotrophic abyssal areas, while stations under high productivity were characterized by different dominant genera and Acantholaimus species, and by a generally low local diversity. Our results corroborate the species-energy hypothesis, where productivity can set a limit to the richness of an ecosystem. Finally, we observed no correlation between sediment

Distinctive Microbial Community Structure in Highly Stratified Deep-Sea Brine Water Columns

KAUST Repository

Bougouffa, Salim; Yang, J. K.; Lee, O. O.; Wang, Y.; Batang, Zenon B.; Al-Suwailem, Abdulaziz M.; Qian, P. Y.

2013-01-01

Atlantis II and Discovery are two hydrothermal and hypersaline deep-sea pools in the Red Sea rift that are characterized by strong thermohalo-stratification and temperatures steadily peaking near the bottom. We conducted comprehensive vertical profiling of the microbial populations in both pools and highlighted the influential environmental factors. Pyrosequencing of the 16S rRNA genes revealed shifts in community structures vis-à-vis depth. High diversity and low abundance were features of the deepest convective layers despite the low cell density. Surprisingly, the brine interfaces had significantly higher cell counts than the overlying deep-sea water, yet they were lowest in diversity. Vertical stratification of the bacterial populations was apparent as we moved from the Alphaproteobacteria-dominated deep sea to the Planctomycetaceae- or Deferribacteres-dominated interfaces to the Gammaproteobacteria-dominated brine layers. Archaeal marine group I was dominant in the deep-sea water and interfaces, while several euryarchaeotic groups increased in the brine. Across sites, microbial phylotypes and abundances varied substantially in the brine interface of Discovery compared with Atlantis II, despite the near-identical populations in the overlying deep-sea waters. The lowest convective layers harbored interestingly similar microbial communities, even though temperature and heavy metal concentrations were very different. Multivariate analysis indicated that temperature and salinity were the major influences shaping the communities. The harsh conditions and the low-abundance phylotypes could explain the observed correlation in the brine pools.

Distinctive Microbial Community Structure in Highly Stratified Deep-Sea Brine Water Columns

KAUST Repository

Bougouffa, Salim

2013-03-29

Atlantis II and Discovery are two hydrothermal and hypersaline deep-sea pools in the Red Sea rift that are characterized by strong thermohalo-stratification and temperatures steadily peaking near the bottom. We conducted comprehensive vertical profiling of the microbial populations in both pools and highlighted the influential environmental factors. Pyrosequencing of the 16S rRNA genes revealed shifts in community structures vis-à-vis depth. High diversity and low abundance were features of the deepest convective layers despite the low cell density. Surprisingly, the brine interfaces had significantly higher cell counts than the overlying deep-sea water, yet they were lowest in diversity. Vertical stratification of the bacterial populations was apparent as we moved from the Alphaproteobacteria-dominated deep sea to the Planctomycetaceae- or Deferribacteres-dominated interfaces to the Gammaproteobacteria-dominated brine layers. Archaeal marine group I was dominant in the deep-sea water and interfaces, while several euryarchaeotic groups increased in the brine. Across sites, microbial phylotypes and abundances varied substantially in the brine interface of Discovery compared with Atlantis II, despite the near-identical populations in the overlying deep-sea waters. The lowest convective layers harbored interestingly similar microbial communities, even though temperature and heavy metal concentrations were very different. Multivariate analysis indicated that temperature and salinity were the major influences shaping the communities. The harsh conditions and the low-abundance phylotypes could explain the observed correlation in the brine pools.

Unexpected Positive Buoyancy in Deep Sea Sharks, Hexanchus griseus, and a Echinorhinus cookei.

Science.gov (United States)

Nakamura, Itsumi; Meyer, Carl G; Sato, Katsufumi

2015-01-01

We do not expect non air-breathing aquatic animals to exhibit positive buoyancy. Sharks, for example, rely on oil-filled livers instead of gas-filled swim bladders to increase their buoyancy, but are nonetheless ubiquitously regarded as either negatively or neutrally buoyant. Deep-sea sharks have particularly large, oil-filled livers, and are believed to be neutrally buoyant in their natural habitat, but this has never been confirmed. To empirically determine the buoyancy status of two species of deep-sea sharks (bluntnose sixgill sharks, Hexanchus griseus, and a prickly shark, Echinorhinus cookei) in their natural habitat, we used accelerometer-magnetometer data loggers to measure their swimming performance. Both species of deep-sea sharks showed similar diel vertical migrations: they swam at depths of 200-300 m at night and deeper than 500 m during the day. Ambient water temperature was around 15°C at 200-300 m but below 7°C at depths greater than 500 m. During vertical movements, all deep-sea sharks showed higher swimming efforts during descent than ascent to maintain a given swimming speed, and were able to glide uphill for extended periods (several minutes), indicating that these deep-sea sharks are in fact positively buoyant in their natural habitats. This positive buoyancy may adaptive for stealthy hunting (i.e. upward gliding to surprise prey from underneath) or may facilitate evening upward migrations when muscle temperatures are coolest, and swimming most sluggish, after spending the day in deep, cold water. Positive buoyancy could potentially be widespread in fish conducting daily vertical migration in deep-sea habitats.

Polarized parton distributions from charged-current deep-inelastic scattering and future neutrino factories

CERN Document Server

Forte, Stefano; Ridolfi, G; Forte, Stefano; Mangano, Michelangelo L.; Ridolfi, Giovanni

2001-01-01

We discuss the determination of polarized parton distributions from charged-current deep-inelastic scattering experiments. We summarize the next-to-leading order treatment of charged-current polarized structure functions, their relation to polarized parton distributions and scale dependence, and discuss their description by means of a next-to-leading order evolution code. We discuss current theoretical expectations and positivity constraints on the unmeasured C-odd combinations Delta q-Delta qbar of polarized quark distributions, and their determination in charged-current deep-inelastic scattering experiments. We give estimates of the expected errors on charged-current structure functions at a future neutrino factory, and perform a study of the accuracy in the determination of polarized parton distributions that would be possible at such a facility. We show that these measurements have the potential to distinguish between different theoretical scenarios for the proton spin structure.

Polarized parton distributions from charged-current deep-inelastic scattering and future neutrino factories

International Nuclear Information System (INIS)

Forte, Stefano; Mangano, Michelangelo L.; Ridolfi, Giovanni

2001-01-01

We discuss the determination of polarized parton distributions from charged-current deep-inelastic scattering experiments. We summarize the next-to-leading-order treatment of charged-current polarized structure functions, their relation to polarized parton distributions and scale dependence, and discuss their description by means of a next-to-leading-order evolution code. We discuss current theoretical expectations and positivity constraints on the unmeasured C-odd combinations Δq-Δq-bar of polarized quark distributions, and their determination in charged-current deep-inelastic scattering experiments. We give estimates of the expected errors on charged-current structure functions at a future neutrino factory, and perform a study of the accuracy in the determination of polarized parton distributions that would be possible at such a facility. We show that these measurements have the potential to distinguish between different theoretical scenarios for the proton spin structure

Methods in mooring deep sea sediment traps

Digital Repository Service at National Institute of Oceanography (India)

Venkatesan, R.; Fernando, V.; Rajaraman, V.S.; Janakiraman, G.

The experience gained during the process of deployment and retrieval of nearly 39 sets of deep sea sediment trap moorings on various ships like FS Sonne, ORV Sagarkanya and DSV Nand Rachit are outlined. The various problems encountered...

An abyssal mobilome: viruses, plasmids and vesicles from deep-sea hydrothermal vents.

Science.gov (United States)

Lossouarn, Julien; Dupont, Samuel; Gorlas, Aurore; Mercier, Coraline; Bienvenu, Nadege; Marguet, Evelyne; Forterre, Patrick; Geslin, Claire

2015-12-01

Mobile genetic elements (MGEs) such as viruses, plasmids, vesicles, gene transfer agents (GTAs), transposons and transpovirions, which collectively represent the mobilome, interact with cellular organisms from all three domains of life, including those thriving in the most extreme environments. While efforts have been made to better understand deep-sea vent microbial ecology, our knowledge of the mobilome associated with prokaryotes inhabiting deep-sea hydrothermal vents remains limited. Here we focus on the abyssal mobilome by reviewing accumulating data on viruses, plasmids and vesicles associated with thermophilic and hyperthermophilic Bacteria and Archaea present in deep-sea hydrothermal vents. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Study of neutrino interactions in the near detector of T2K

International Nuclear Information System (INIS)

Ferchichi, Chiraz

2014-01-01

The T2K experiment studies the properties of neutrinos, particularly neutrino oscillations. It takes place in Japan and uses a muonic neutrino beam produced by the J-PARC accelerator complex, a near detector, ND280 on the J-PARC site in order to characterise the beam, and a far detector, Super-Kamiokande 295 km away in order to measure the neutrino oscillations. The near detector is also used to study the neutrino interactions and the goal of this thesis is the measurement of muonic neutrino deep inelastic scattering cross sections.The thesis first introduces neutrino physics, then the T2K experiment and more particularly the time projection chambers of the near detector, and its data quality checking that I was in charge of. The analysis is based on the T2K data recorded until 2013. The selection of charged current muonic neutrino interactions is then presented, as well as a preliminary study of the selection of charged current muonic neutrino interactions with the production of a neutral pion. A criterion on track multiplicity allows enriching the former sample in interactions corresponding to a neutrino deep inelastic scattering. Finally a fit, first validated on simulated data, allows the extraction of the muonic neutrino deep inelastic scattering cross sections. (author) [fr

Effects of hydrostatic pressure on yeasts isolated from deep-sea hydrothermal vents.

Science.gov (United States)

Burgaud, Gaëtan; Hué, Nguyen Thi Minh; Arzur, Danielle; Coton, Monika; Perrier-Cornet, Jean-Marie; Jebbar, Mohamed; Barbier, Georges

2015-11-01

Hydrostatic pressure plays a significant role in the distribution of life in the biosphere. Knowledge of deep-sea piezotolerant and (hyper)piezophilic bacteria and archaea diversity has been well documented, along with their specific adaptations to cope with high hydrostatic pressure (HHP). Recent investigations of deep-sea microbial community compositions have shown unexpected micro-eukaryotic communities, mainly dominated by fungi. Molecular methods such as next-generation sequencing have been used for SSU rRNA gene sequencing to reveal fungal taxa. Currently, a difficult but fascinating challenge for marine mycologists is to create deep-sea marine fungus culture collections and assess their ability to cope with pressure. Indeed, although there is no universal genetic marker for piezoresistance, physiological analyses provide concrete relevant data for estimating their adaptations and understanding the role of fungal communities in the abyss. The present study investigated morphological and physiological responses of fungi to HHP using a collection of deep-sea yeasts as a model. The aim was to determine whether deep-sea yeasts were able to tolerate different HHP and if they were metabolically active. Here we report an unexpected taxonomic-based dichotomic response to pressure with piezosensitve ascomycetes and piezotolerant basidiomycetes, and distinct morphological switches triggered by pressure for certain strains. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Deep-Sea Mining With No Net Loss of Biodiversity—An Impossible Aim

Directory of Open Access Journals (Sweden)

Holly J. Niner

2018-03-01

Full Text Available Deep-sea mining is likely to result in biodiversity loss, and the significance of this to ecosystem function is not known. “Out of kind” biodiversity offsets substituting one ecosystem type (e.g., coral reefs for another (e.g., abyssal nodule fields have been proposed to compensate for such loss. Here we consider a goal of no net loss (NNL of biodiversity and explore the challenges of applying this aim to deep seabed mining, based on the associated mitigation hierarchy (avoid, minimize, remediate. We conclude that the industry cannot at present deliver an outcome of NNL. This results from the vulnerable nature of deep-sea environments to mining impacts, currently limited technological capacity to minimize harm, significant gaps in ecological knowledge, and uncertainties of recovery potential of deep-sea ecosystems. Avoidance and minimization of impacts are therefore the only presently viable means of reducing biodiversity losses from seabed mining. Because of these constraints, when and if deep-sea mining proceeds, it must be approached in a precautionary and step-wise manner to integrate new and developing knowledge. Each step should be subject to explicit environmental management goals, monitoring protocols, and binding standards to avoid serious environmental harm and minimize loss of biodiversity. “Out of kind” measures, an option for compensation currently proposed, cannot replicate biodiversity and ecosystem services lost through mining of the deep seabed and thus cannot be considered true offsets. The ecosystem functions provided by deep-sea biodiversity contribute to a wide range of provisioning services (e.g., the exploitation of fish, energy, pharmaceuticals, and cosmetics, play an essential role in regulatory services (e.g., carbon sequestration and are important culturally. The level of “acceptable” biodiversity loss in the deep sea requires public, transparent, and well-informed consideration, as well as wide agreement

Fungi and macroaggregation in deep-sea sediments

Digital Repository Service at National Institute of Oceanography (India)

Damare, S.R.; Raghukumar, C.

Whereas fungi in terrestrial soils have been well studied, little is known of them in deep-sea sediments. Recent studies have demonstrated the presence of fungal hyphae in such sediments but in low abundance. We present evidence in this study...

Trophic ecology of deep-sea Asteroidea (Echinodermata) from eastern Canada

Science.gov (United States)

Gale, Katie S. P.; Hamel, Jean-François; Mercier, Annie

2013-10-01

Asteroids (sea stars) can be important predators in benthic communities and are often present in ecologically important and vulnerable deep-sea coral and sponge habitats. However, explicit studies on the trophic ecology of deep-sea asteroids are rare. We investigated the diets of seven species of deep-sea asteroid from the bathyal zone of Newfoundland and Labrador, eastern Canada. A multifaceted approach including live animal observations, stomach content analysis, and stable isotope analysis revealed the asteroids to be either top predators of megafauna or secondary consumers (mud ingesters, infaunal predators, and suspension feeders). The stable isotope signatures of Ceramaster granularis, Hippasteria phrygiana, and Mediaster bairdi are characteristic of high-level predators, having δ15N values 4.4‰ (more than one trophic level) above Ctenodiscus crispatus, Leptychaster arcticus, Novodinia americana, and Zoroaster fulgens. We present strong evidence that corals and sponges are common food items for two of the predatory species, C. granularis and H. phrygiana. During laboratory feeding trials, live H. phrygiana fed on several species of soft coral and C. granularis fed on sponges. Stomach content analysis of wild-caught individuals revealed sclerites from sea pens (e.g. Pennatula sp.) in the stomachs of both asteroid species; H. phrygiana also contained sclerites from at least two other species of octocoral and siliceous sponge spicules were present in the stomachs of C. granularis. The stomach contents of the secondary consumers contained a range of invertebrate material. Leptychaster arcticus and Ctenodiscus crispatus feed infaunally on bulk sediment and molluscs, Zoroaster fulgens is a generalist infaunal predator, and the brisingid Novodinia americana is a specialist suspension feeder on benthopelagic crustaceans. This study provides a foundation for understanding the ecological roles of bathyal asteroids, and suggests that some species may have the

Cosmopolitanism and Biogeography of the Genus Manganonema (Nematoda: Monhysterida in the Deep Sea

Directory of Open Access Journals (Sweden)

Roberto Danovaro

2011-09-01

Full Text Available Spatial patterns of species diversity provide information about the mechanisms that regulate biodiversity and are important for setting conservation priorities. Present knowledge of the biogeography of meiofauna in the deep sea is scarce. This investigation focuses on the distribution of the deep-sea nematode genus Manganonema, which is typically extremely rare in deep-sea sediment samples. Forty-four specimens of eight different species of this genus were recorded from different Atlantic and Mediterranean regions. Four out of the eight species encountered are new to science. We report here that this genus is widespread both in the Atlantic and in the Mediterranean Sea. These new findings together with literature information indicate that Manganonema is a cosmopolitan genus, inhabiting a variety of deep-sea habitats and oceans. Manganonema shows the highest diversity at water depths >4,000 m. Our data, therefore, indicate that this is preferentially an abyssal genus that is able, at the same time, to colonize specific habitats at depths shallower than 1,000 m. The analysis of the distribution of the genus Manganonema indicates the presence of large differences in dispersal strategies among different species, ranging from locally endemic to cosmopolitan. Lacking meroplanktonic larvae and having limited dispersal ability due to their small size, it has been hypothesized that nematodes have limited dispersal potential. However, the investigated deep-sea nematodes were present across different oceans covering macro-scale distances. Among the possible explanations (hydrological conditions, geographical and geological pathways, long-term processes, specific historical events, their apparent preference of colonizing highly hydrodynamic systems, could suggest that these infaunal organisms are transported by means of deep-sea benthic storms and turbidity currents over long distances.

Unexpected Positive Buoyancy in Deep Sea Sharks, Hexanchus griseus, and a Echinorhinus cookei.

Directory of Open Access Journals (Sweden)

Itsumi Nakamura

Full Text Available We do not expect non air-breathing aquatic animals to exhibit positive buoyancy. Sharks, for example, rely on oil-filled livers instead of gas-filled swim bladders to increase their buoyancy, but are nonetheless ubiquitously regarded as either negatively or neutrally buoyant. Deep-sea sharks have particularly large, oil-filled livers, and are believed to be neutrally buoyant in their natural habitat, but this has never been confirmed. To empirically determine the buoyancy status of two species of deep-sea sharks (bluntnose sixgill sharks, Hexanchus griseus, and a prickly shark, Echinorhinus cookei in their natural habitat, we used accelerometer-magnetometer data loggers to measure their swimming performance. Both species of deep-sea sharks showed similar diel vertical migrations: they swam at depths of 200-300 m at night and deeper than 500 m during the day. Ambient water temperature was around 15°C at 200-300 m but below 7°C at depths greater than 500 m. During vertical movements, all deep-sea sharks showed higher swimming efforts during descent than ascent to maintain a given swimming speed, and were able to glide uphill for extended periods (several minutes, indicating that these deep-sea sharks are in fact positively buoyant in their natural habitats. This positive buoyancy may adaptive for stealthy hunting (i.e. upward gliding to surprise prey from underneath or may facilitate evening upward migrations when muscle temperatures are coolest, and swimming most sluggish, after spending the day in deep, cold water. Positive buoyancy could potentially be widespread in fish conducting daily vertical migration in deep-sea habitats.

75 FR 49420 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

Science.gov (United States)

2010-08-13

.... 100513223-0289-02] RIN 0648-AY88 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications In- season Adjustment AGENCY: National Marine...-sea (DAS) allocation for the Atlantic deep- sea red crab fishery that were implemented in May 2010...

Results from the ANTARES neutrino telescope

Directory of Open Access Journals (Sweden)

Losa Agustín Sánchez

2017-01-01

Full Text Available The ANTARES detector is an underwater neutrino telescope, the largest in the Northern Hemisphere and the first one ever built under the sea, located in the Mediterranean Sea 40 km off the Southern coast of France, at a depth of 2.5 km. It comprises 885 photomultiplier tubes distributed along twelve detection lines. The signal due to neutrinos is searched by reconstructing the tracks of secondary particles produced in the surroundings of the detector. The detector is in data taking with its final configuration since 2008. It is aimed at identifying the sources, either steady or flaring, of cosmic neutrinos, and is also suitable for detection of dark matter within the Sun and/or Galactic Centre. ANTARES can contribute in the confirmation of the cosmic neutrino flux observed by IceCube, being particularly competitive for the Galactic Centre, and in general for galactic sources, due its latitude and at lower energies and softer spectra due its configuration. Several multi-messenger analyses have been also attempted, including the search of coincidence signals of neutrinos with gravitational-waves. Additional topics include neutrino oscillations or the search of exotic particles, like nuclearites and magnetic monopoles. Results from the latest analyses are presented.

Starvation and recovery in the deep-sea methanotroph Methyloprofundus sedimenti.

Science.gov (United States)

Tavormina, Patricia L; Kellermann, Matthias Y; Antony, Chakkiath Paul; Tocheva, Elitza I; Dalleska, Nathan F; Jensen, Ashley J; Valentine, David L; Hinrichs, Kai-Uwe; Jensen, Grant J; Dubilier, Nicole; Orphan, Victoria J

2017-01-01

In the deep ocean, the conversion of methane into derived carbon and energy drives the establishment of diverse faunal communities. Yet specific biological mechanisms underlying the introduction of methane-derived carbon into the food web remain poorly described, due to a lack of cultured representative deep-sea methanotrophic prokaryotes. Here, the response of the deep-sea aerobic methanotroph Methyloprofundus sedimenti to methane starvation and recovery was characterized. By combining lipid analysis, RNA analysis, and electron cryotomography, it was shown that M. sedimenti undergoes discrete cellular shifts in response to methane starvation, including changes in headgroup-specific fatty acid saturation levels, and reductions in cytoplasmic storage granules. Methane starvation is associated with a significant increase in the abundance of gene transcripts pertinent to methane oxidation. Methane reintroduction to starved cells stimulates a rapid, transient extracellular accumulation of methanol, revealing a way in which methane-derived carbon may be routed to community members. This study provides new understanding of methanotrophic responses to methane starvation and recovery, and lays the initial groundwork to develop Methyloprofundus as a model chemosynthesizing bacterium from the deep sea. © 2016 John Wiley & Sons Ltd.

Predicted deep-sea coral habitat suitability for the U.S. West coast.

Directory of Open Access Journals (Sweden)

John M Guinotte

Full Text Available Regional scale habitat suitability models provide finer scale resolution and more focused predictions of where organisms may occur. Previous modelling approaches have focused primarily on local and/or global scales, while regional scale models have been relatively few. In this study, regional scale predictive habitat models are presented for deep-sea corals for the U.S. West Coast (California, Oregon and Washington. Model results are intended to aid in future research or mapping efforts and to assess potential coral habitat suitability both within and outside existing bottom trawl closures (i.e. Essential Fish Habitat (EFH and identify suitable habitat within U.S. National Marine Sanctuaries (NMS. Deep-sea coral habitat suitability was modelled at 500 m×500 m spatial resolution using a range of physical, chemical and environmental variables known or thought to influence the distribution of deep-sea corals. Using a spatial partitioning cross-validation approach, maximum entropy models identified slope, temperature, salinity and depth as important predictors for most deep-sea coral taxa. Large areas of highly suitable deep-sea coral habitat were predicted both within and outside of existing bottom trawl closures and NMS boundaries. Predicted habitat suitability over regional scales are not currently able to identify coral areas with pin point accuracy and probably overpredict actual coral distribution due to model limitations and unincorporated variables (i.e. data on distribution of hard substrate that are known to limit their distribution. Predicted habitat results should be used in conjunction with multibeam bathymetry, geological mapping and other tools to guide future research efforts to areas with the highest probability of harboring deep-sea corals. Field validation of predicted habitat is needed to quantify model accuracy, particularly in areas that have not been sampled.

Deep-sea environment and biodiversity of the West African Equatorial margin

Science.gov (United States)

Sibuet, Myriam; Vangriesheim, Annick

2009-12-01

The long-term BIOZAIRE multidisciplinary deep-sea environmental program on the West Equatorial African margin organized in partnership between Ifremer and TOTAL aimed at characterizing the benthic community structure in relation with physical and chemical processes in a region of oil and gas interest. The morphology of the deep Congo submarine channel and the sedimentological structures of the deep-sea fan were established during the geological ZAIANGO project and helped to select study sites ranging from 350 to 4800 m water depth inside or near the channel and away from its influence. Ifremer conducted eight deep-sea cruises on board research vessels between 2000 and 2005. Standardized methods of sampling together with new technologies such as the ROV Victor 6000 and its associated instrumentation were used to investigate this poorly known continental margin. In addition to the study of sedimentary environments more or less influenced by turbidity events, the discovery of one of the largest cold seeps near the Congo channel and deep coral reefs extends our knowledge of the different habitats of this margin. This paper presents the background, objectives and major results of the BIOZAIRE Program. It highlights the work achieved in the 16 papers in this special issue. This synthesis paper describes the knowledge acquired at a regional and local scale of the Equatorial East Atlantic margin, and tackles new interdisciplinary questions to be answered in the various domains of physics, chemistry, taxonomy and ecology to better understand the deep-sea environment in the Gulf of Guinea.

75 FR 35435 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

Science.gov (United States)

2010-06-22

.... 100513223-0254-01] RIN 0648-AY88 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications In- season Adjustment AGENCY: National Marine... deep-sea red crab fishery, including a target total allowable catch (TAC) and a fleet-wide days-at-sea...

Characterization of bacterial diversity associated with deep sea ferromanganese nodules from the South China Sea.

Science.gov (United States)

Zhang, De-Chao; Liu, Yan-Xia; Li, Xin-Zheng

2015-09-01

Deep sea ferromanganese (FeMn) nodules contain metallic mineral resources and have great economic potential. In this study, a combination of culture-dependent and culture-independent (16S rRNA genes clone library and pyrosequencing) methods was used to investigate the bacterial diversity in FeMn nodules from Jiaolong Seamount, the South China Sea. Eleven bacterial strains including some moderate thermophiles were isolated. The majority of strains belonged to the phylum Proteobacteria; one isolate belonged to the phylum Firmicutes. A total of 259 near full-length bacterial 16S rRNA gene sequences in a clone library and 67,079 valid reads obtained using pyrosequencing indicated that members of the Gammaproteobacteria dominated, with the most abundant bacterial genera being Pseudomonas and Alteromonas. Sequence analysis indicated the presence of many organisms whose closest relatives are known manganese oxidizers, iron reducers, hydrogen-oxidizing bacteria and methylotrophs. This is the first reported investigation of bacterial diversity associated with deep sea FeMn nodules from the South China Sea.

First Search for the EMC Effect and Nuclear Shadowing in Neutrino Nucleus Deep Inelastic Scattering at MINERvA

Energy Technology Data Exchange (ETDEWEB)

Mousseau, Joel A. [Univ. of Florida, Gainesville, FL (United States)

2015-01-01

Decades of research in electron-nucleus deep inelastic scattering (DIS) have provided a clear picture of nuclear physics at high momentum transfer. While these effects have been clearly demonstrated by experiment, the theoretical explanation of their origin in some kinematic regions has been lacking. Particularly, the effects in the intermediate regions of Bjorken-x, anti-shadowing and the EMC effect have no universally accepted quantum mechanical explanation. In addition, these effects have not been measured systematically with neutrino-nucleus deep inelastic scattering, due to experiments lacking multiple heavy targets.

Potential Osteoporosis Recovery by Deep Sea Water through Bone Regeneration in SAMP8 Mice

Directory of Open Access Journals (Sweden)

Hen-Yu Liu

2013-01-01

Full Text Available The aim of this study is to examine the therapeutic potential of deep sea water (DSW on osteoporosis. Previously, we have established the ovariectomized senescence-accelerated mice (OVX-SAMP8 and demonstrated strong recovery of osteoporosis by stem cell and platelet-rich plasma (PRP. Deep sea water at hardness (HD 1000 showed significant increase in proliferation of osteoblastic cell (MC3T3 by MTT assay. For in vivo animal study, bone mineral density (BMD was strongly enhanced followed by the significantly increased trabecular numbers through micro-CT examination after a 4-month deep sea water treatment, and biochemistry analysis showed that serum alkaline phosphatase (ALP activity was decreased. For stage-specific osteogenesis, bone marrow-derived stromal cells (BMSCs were harvested and examined. Deep sea water-treated BMSCs showed stronger osteogenic differentiation such as BMP2, RUNX2, OPN, and OCN, and enhanced colony forming abilities, compared to the control group. Interestingly, most untreated OVX-SAMP8 mice died around 10 months; however, approximately 57% of DSW-treated groups lived up to 16.6 months, a life expectancy similar to the previously reported life expectancy for SAMR1 24 months. The results demonstrated the regenerative potentials of deep sea water on osteogenesis, showing that deep sea water could potentially be applied in osteoporosis therapy as a complementary and alternative medicine (CAM.

A Dataset of Deep-Sea Fishes Surveyed by Research Vessels in the Waters around Taiwan

Directory of Open Access Journals (Sweden)

Kwang-Tsao Shao

2014-12-01

Full Text Available The study of deep-sea fish fauna is hampered by a lack of data due to the difficulty and high cost incurred in its surveys and collections. Taiwan is situated along the edge of the Eurasia fig, at the junction of three Large Marine Ecosystems or Ecoregions of the East China Sea, South China Sea and the Philippines. As nearly two-thirds of its surrounding marine ecosystems are deep-sea environments, Taiwan is expected to hold a rich diversity of deep-sea fish. However, in the past, no research vessels were employed to collect fish data on site. Only specimens, caught by bottom trawl fishing in the waters hundreds of meters deep and missing precise locality information, were collected from Dasi and Donggang fishing harbors. Began in 2001, with the support of National Science Council, research vessels were made available to take on the task of systematically collecting deep-sea fish specimens and occurrence records in the waters surrounding Taiwan. By the end of 2006, a total of 3,653 specimens, belonging to 26 orders, 88 families, 198 genera and 366 species, were collected in addition to data such as sampling site geographical coordinates and water depth, and fish body length and weight. The information, all accessible from the “Database of Taiwan’s Deep-Sea Fauna and Its Distribution (http://deepsea.biodiv.tw/” as part of the “Fish Database of Taiwan,” can benefit the study of temporal and spatial changes in distribution and abundance of fish fauna in the context of global deep-sea biodiversity.

Restoration of deep-sea macrofauna after simulated benthic disturbance in the Central Indian Basin

Digital Repository Service at National Institute of Oceanography (India)

Ingole, B.S.; Pavithran, S.; Ansari, Z.A.

feeding by holoyhurians in the deep sea: some observations and comments. Progress in Oceanography 50, 407-421. Glasby, G.P., 1977. Marine manganese deposits. Elsevier, Amsterdam, pp.523. Grassle, J.F. and Sanders, H.L., 1973. Life histories and role... gesamten Hydrobiologie 77, 331-339. Thiel, H., 2001. Use and protection of the deep sea - an introduction. Deep-Sea Research II 48, (17-18), 3427-3431. Trueblood, D., Ozturgut, E., Pilipchuk, M., Gloumov, I. 1997. The ecological impacts of the joint U...

The neutrino mass hierarchy measurement with a neutrino telescope in the Mediterranean Sea: A feasibility study

Energy Technology Data Exchange (ETDEWEB)

Tsirigotis, A. G. [Physics Laboratory, Hellenic Open University (Greece); Collaboration: KM3NeT Collaboration

2014-11-18

With the measurement of a non zero value of the θ{sub 13} neutrino mixing parameter, interest in neutrinos as source of the baryon asymmetry of the universe has increased. Among the measurements of a rich and varied program in near future neutrino physics is the determination of the mass hierarchy. We present the status of a study of the feasibility of using a densely instrumented undersea neutrino detector to determine the mass hierarchy, utilizing the Mikheyev-Smirnov-Wolfenstein (MSW) effect on atmospheric neutrino oscillations. The detector will use technology developed for KM3NeT. We present the systematic studies of the optimization of a detector in the required 5–10 GeV energy regime. These studies include new tracking and interaction identification algorithms as well as geometrical optimizations of the detector.

Impact of Deepwater Horizon Spill on food supply to deep-sea benthos communities

Science.gov (United States)

Prouty, Nancy G.; Swarzenski, Pamela; Mienis, Furu; Duineveld, Gerald; Demopoulos, Amanda W.J.; Ross, Steve W.; Brooke, Sandra

2016-01-01

Deep-sea ecosystems encompass unique and often fragile communities that are sensitive to a variety of anthropogenic and natural impacts. After the 2010 Deepwater Horizon (DWH) oil spill, sampling efforts documented the acute impact of the spill on some deep-sea coral colonies. To investigate the impact of the DWH spill on quality and quantity of biomass delivered to the deep-sea, a suite of geochemical tracers (e.g., stable and radio-isotopes, lipid biomarkers, and compound specific isotopes) was measured from monthly sediment trap samples deployed near a high-density deep-coral site in the Viosca Knoll area of the north-central Gulf of Mexico prior to (Oct-2008 to Sept-2009) and after the spill (Oct-10 to Sept-11). Marine (e.g., autochthonous) sources of organic matter dominated the sediment traps in both years, however after the spill, there was a pronounced reduction in marinesourced OM, including a reduction in marine-sourced sterols and n-alkanes and a concomitant decrease in sediment trap organic carbon and pigment flux. Results from this study indicate a reduction in primary production and carbon export to the deep-sea in 2010-2011, at least 6-18 months after the spill started. Whereas satellite observations indicate an initial increase in phytoplankton biomass, results from this sediment trap study define a reduction in primary production and carbon export to the deep-sea community. In addition, a dilution from a low-14C carbon source (e.g., petrocarbon) was detected in the sediment trap samples after the spill, in conjunction with a change in the petrogenic composition. The data presented here fills a critical gap in our knowledge of biogeochemical processes and sub-acute impacts to the deep-sea that ensued after the 2010 DWH spill.

Reliability considerations of electronics components for the deep underwater muon and neutrino detection system

International Nuclear Information System (INIS)

Leskovar, B.

1980-02-01

The reliability of some electronics components for the Deep Underwater Muon and Neutrino Detection (DUMAND) System is discussed. An introductory overview of engineering concepts and technique for reliability assessment is given. Component reliability is discussed in the contest of major factors causing failures, particularly with respect to physical and chemical causes, process technology and testing, and screening procedures. Failure rates are presented for discrete devices and for integrated circuits as well as for basic electronics components. Furthermore, the military reliability specifications and standards for semiconductor devices are reviewed

Some consequences of a scale-breaking model in electron and neutrino deep inelastic scattering

International Nuclear Information System (INIS)

Fernandez Pacheco, A.; Grifols, J.A.; Schmidt, I.A.

1978-01-01

Electron and neutrino deep inelastic processes, extending a simple parton model explanation of the approach to scaling observed in electroproduction at large x are analyzed. The model is successful in fitting the present experimental data without any explicit effects from asymptotic freedom or new quarks. This model has a large q 2 behaviour which is quite different from that expected in asymptotic freedom (AF) theories and comparisons to data can be used to sharpen any experimental demonstration of AF effects. Of course, the model is consistent with AF and both effects could be present

The neutrino hunters the chase for the ghost particle and the secrets of the universe

CERN Document Server

Jayawardhana, Ray

2014-01-01

In Neutrino Hunters, the renowned astrophysicist and award-winning writer Ray Jayawardhana takes us on a thrilling journey into the shadowy world of neutrinos and the colorful lives of those who seek them. Demystifying particle science along the way, Jayawardhana tells a detective story with cosmic implications—interweaving tales of the sharp-witted theorist Wolfgang Pauli; the troubled genius Ettore Majorana; the harbinger of the atomic age Enrico Fermi; the notorious Cold War defector Bruno Pontecorvo; and the dynamic dream team of Marie and Pierre Curie. Then there are the scientists of today who have caught the neutrino bug, and whose experimental investigations stretch from a working nickel mine in Ontario to a long tunnel through a mountain in central Italy, from a nuclear waste site in New Mexico to a bay on the South China Sea, and from Olympic-size pools deep underground to a gigantic cube of Antarctic ice—called, naturally, IceCube. As Jayawardhana recounts a captivating saga of scientific disc...

Development of sensors for the acoustic detection of ultra high energy neutrinos in the deep sea

International Nuclear Information System (INIS)

Naumann, C.L.

2007-01-01

In addition to the optical detection system used by the ANTARES detector, a proposal was made to include an acoustic system consisting of several modified ANTARES storeys to investigate the feasibility of building and operating an acoustic particle detection system in the deep sea and at the same time perform an extensive study of the acoustic properties of the deep sea environment. The directional characteristics of the sensors and their placement within the ANTARES detector had to be optimised for the study of the correlation properties of the acoustic noise at different length scales - from below a metre to above 100 metres. The so-called ''equivalent circuit diagram (=ECD) model'' - was applied to predict the acoustic properties of piezo elements, such as sensitivity and intrinsic noise, and was extended by including effects resulting from the geometrical shape of the sensors. A procedure was devised to gain the relevant ECD parameters from electrical impedance measurements of the piezo elements, both free and coupled to a surrounding medium. Based on the findings of this ECD model, intensive design studies were performed with prototype hydrophones using piezo elements as active sensors. The design best suited for the construction of acoustic sensors for ANTARES was determined, and a total of twelve hydrophones were built with a sensitivity of -145 to -140 dB re 1V/μPa between 5 and 50 kHz and an intrinsic noise power density around -90 dB re 1 V/√(Hz), giving a total noise rms of 7 mV in this frequency range. The hydrophones were pressure tested and calibrated for integration into the ANTARES acoustic system. In addition, three so-called Acoustic Modules, sensors in pressure resistant glass spheres with a sensitive bandwidth of about 80 kHz, were developed and built. The calibration procedure employed during the sensor design studies as well as for the final sensors to be installed in the ANTARES framework is presented, together with exemplary results for

Development of sensors for the acoustic detection of ultra high energy neutrinos in the deep sea

Energy Technology Data Exchange (ETDEWEB)

Naumann, C.L.

2007-09-17

In addition to the optical detection system used by the ANTARES detector, a proposal was made to include an acoustic system consisting of several modified ANTARES storeys to investigate the feasibility of building and operating an acoustic particle detection system in the deep sea and at the same time perform an extensive study of the acoustic properties of the deep sea environment. The directional characteristics of the sensors and their placement within the ANTARES detector had to be optimised for the study of the correlation properties of the acoustic noise at different length scales - from below a metre to above 100 metres. The so-called 'equivalent circuit diagram (=ECD) model' - was applied to predict the acoustic properties of piezo elements, such as sensitivity and intrinsic noise, and was extended by including effects resulting from the geometrical shape of the sensors. A procedure was devised to gain the relevant ECD parameters from electrical impedance measurements of the piezo elements, both free and coupled to a surrounding medium. Based on the findings of this ECD model, intensive design studies were performed with prototype hydrophones using piezo elements as active sensors. The design best suited for the construction of acoustic sensors for ANTARES was determined, and a total of twelve hydrophones were built with a sensitivity of -145 to -140 dB re 1V/{mu}Pa between 5 and 50 kHz and an intrinsic noise power density around -90 dB re 1 V/{radical}(Hz), giving a total noise rms of 7 mV in this frequency range. The hydrophones were pressure tested and calibrated for integration into the ANTARES acoustic system. In addition, three so-called Acoustic Modules, sensors in pressure resistant glass spheres with a sensitive bandwidth of about 80 kHz, were developed and built. The calibration procedure employed during the sensor design studies as well as for the final sensors to be installed in the ANTARES framework is presented, together with

Possibility of observing high energy neutrinos from gamma bursts, with the Antanares telescope, feasibility study; Possibilite d'observation, par le telescope antares, de neutrinos de haute energie associes aux sursauts gamma et validation des techniques de detection a l'aide d'un prototype

Energy Technology Data Exchange (ETDEWEB)

Kouchner, A

2001-04-01

The European Antares collaboration intends to build a deep-sea neutrino telescope with a detection surface of about 1/10 km{sup 2} in the Mediterranean sea. The universe is transparent to neutrinos, so their study provides a unique means of improving our knowledge of the nature and origin of cosmic rays and their emission from the most powerful astrophysical sources in the cosmos. Neutrinos also offer the possibility of opening a new energy window (E>TeV) for observation of the universe. The first part of the thesis is dedicated to a study of the possibility of using the future telescope to look for correlations between gamma-ray bursts and high-energy neutrinos. It is based, on one hand, on the predictions of neutrino fluxes from gamma-ray bursts in the framework of the theoretical model of 'fireballs', and, on the other hand, on the temporal properties of the gamma-ray bursts in the 4. BATSE catalogue. The second part of the thesis presents the results obtained with a prototype detector line deployed, at the end of 1999, some forty km south-west off Marseilles. The objective was to operate a complete apparatus, similar to the future detector lines, from the shore, and under realistic conditions. Data from 7 photomultiplier tubes disposed along the detector line were transmitted through 37 km of optical fiber to the shore, where they were used to reconstruct tracks due to atmospheric muons, thus validating the detection principles and methods. (author)

Sensitivity of the deep-sea amphipod Eurythenes gryllus to chemically dispersed oil.

Science.gov (United States)

Olsen, Gro Harlaug; Coquillé, Nathalie; Le Floch, Stephane; Geraudie, Perrine; Dussauze, Matthieu; Lemaire, Philippe; Camus, Lionel

2016-04-01

In the context of an oil spill accident and the following oil spill response, much attention is given to the use of dispersants. Dispersants are used to disperse an oil slick from the sea surface into the water column generating a cloud of dispersed oil droplets. The main consequence is an increasing of the sea water-oil interface which induces an increase of the oil biodegradation. Hence, the use of dispersants can be effective in preventing oiling of sensitive coastal environments. Also, in case of an oil blowout from the seabed, subsea injection of dispersants may offer some benefits compared to containment and recovery of the oil or in situ burning operation at the sea surface. However, biological effects of dispersed oil are poorly understood for deep-sea species. Most effects studies on dispersed oil and also other oil-related compounds have been focusing on more shallow water species. This is the first approach to assess the sensitivity of a macro-benthic deep-sea organism to dispersed oil. This paper describes a toxicity test which was performed on the macro-benthic deep-sea amphipod (Eurythenes gryllus) to determine the concentration causing lethality to 50% of test individuals (LC50) after an exposure to dispersed Brut Arabian Light (BAL) oil. The LC50 (24 h) was 101 and 24 mg L(-1) after 72 h and 12 mg L(-1) at 96 h. Based on EPA scale of toxicity categories to aquatic organisms, an LC50 (96 h) of 12 mg L(-1) indicates that the dispersed oil was slightly to moderately toxic to E. gryllus. As an attempt to compare our results to others, a literature study was performed. Due to limited amount of data available for dispersed oil and amphipods, information on other crustacean species and other oil-related compounds was also collected. Only one study on dispersed oil and amphipods was found, the LC50 value in this study was similar to the LC50 value of E. gryllus in our study. Since toxicity data are important input to risk assessment and net environmental

Sorption of americium and neptunium by deep-sea sediments

International Nuclear Information System (INIS)

Higgo, J.J.W.; Rees, L.V.C.; Cronan, D.S.

1983-01-01

The sorption and desorption of americium and neptunium by a wide range of deep-sea sediments from natural sea water at 4 0 C has been studied using a carefully controlled batch technique. All the sediments studied should form an excellent barrier to the migration of americium since distribution coefficients were uniformly greater than 10 5 and the sorption-desorption reaction may not be reversible. The sorption of neptunium was reversible and, except for one red clay, the distribution coefficients were greater than 10 3 for all the sediments investigated. Nevertheless the migration of neptunium should also be effectively retarded by most deep-sea sediments even under relatively oxidizing conditions. The neptunium in solution remained in the V oxidation state throughout the experiments. Under the experimental conditions used colloidal americium was trapped by the sediment and solubility did not seem to be the controlling factor in the desorption of americium. (Auth.)

Experimental research on the structural instability mechanism and the effect of multi-echelon support of deep roadways in a kilometre-deep well.

Directory of Open Access Journals (Sweden)

Rui Peng

Full Text Available We study the structural instability mechanism and effect of a multi-echelon support in very-deep roadways. We conduct a scale model test for analysing the structural failure mechanism and the effect of multi-echelon support of roadways under high horizontal stress. Mechanical bearing structures are classified according to their secondary stress distribution and the strength degradation of the surrounding rock after roadway excavation. A new method is proposed by partitioning the mechanical bearing structure of the surrounding rock into weak, key and main coupling bearing stratums. In the surrounding rock, the main bearing stratum is the plastic reshaping and flowing area. The weak bearing stratum is the peeling layer or the caving part. And the key bearing stratum is the shearing and yielding area. The structural fracture mechanism of roadways is considered in analysing the bearing structure instability of the surrounding rock, and multi-echelon support that considers the structural characteristics of roadway bearings is proposed. Results of the experimental study indicate that horizontal pressure seriously influences the stability of the surrounding rock, as indicated by extension of the weak bearing area and the transfer of the main and key bearing zones. The falling roof, rib spalling, and floor heave indicate the decline of the bearing capacity of surrounding rock, thereby causing roadway structural instability. Multi-echelon support is proposed according to the mechanical bearing structure of the surrounding rock without support. The redesigned support can reduce the scope of the weak bearing area and limit the transfer of the main and key bearing areas. Consequently, kilometre-deep roadway disasters, such as wedge roof caving, floor heave, and rib spalling, can be avoided to a certain degree, and plastic flow in the surrounding rock is relieved. The adverse effect of horizontal stress on the vault, spandrel and arch foot decreases. The

Observation of oscillations of atmospheric neutrinos with the IceCube Neutrino Observatory

International Nuclear Information System (INIS)

Euler, Sebastian

2014-01-01

Neutrino oscillations have become one of the most important research topics in particle physics since their discovery 15 years ago. In the past, the study of neutrino oscillations has been largely the domain of dedicated experiments, but in the last year also the large-volume neutrino telescopes ANTARES and IceCube reported their results on the oscillations of atmospheric muon neutrinos and thus joined the community of experiments studying neutrino oscillations. The precision of their results is not yet competitive, but their sheer size and the consequently enormous statistics give rise to the expectation of a competitive measurement in the future. This thesis describes an analysis that was done on IceCube data taken with the nearly complete detector in the years 2010/2011. IceCube is the world's largest neutrino detector, located at the geographic South Pole, where it uses the Antarctic ice sheet as its detection medium. It detects neutrinos interacting within or close to the instrumented volume by observing the Cherenkov light which is emitted by secondary particles produced in these interactions. An array of optical sensors deployed within a cubic kilometer of ice detects the Cherenkov light and makes it possible to reconstruct the energy and direction of the initial neutrino. Unfortunately, IceCube detects not only neutrinos: the desired neutrino signal is buried in a huge background of atmospheric muons, produced in air showers induced by cosmic rays. This background has to be rejected first. The analysis presented here employs an event selection that is based on the idea of using the outer layers of IceCube as an active veto against the background of atmospheric muons and achieves the necessary background rejection of more than 6 orders of magnitude while keeping a high-statistics sample of several thousands of muon neutrinos. In contrast to the earlier IceCube analysis, which used only the zenith angle, it then performs a 2-dimensional likelihood fit on

Stakeholder perspectives on the importance of rare-species research for deep-sea environmental management

Science.gov (United States)

Turner, Phillip J.; Campbell, Lisa M.; Van Dover, Cindy L.

2017-07-01

The apparent prevalence of rare species (rarity) in the deep sea is a concern for environmental management and conservation of biodiversity. Rare species are often considered at risk of extinction and, in terrestrial and shallow water environments, have been shown to play key roles within an ecosystem. In the deep-sea environment, current research focuses primarily on abundant species and deep-sea stakeholders are questioning the importance of rare species in ecosystem functioning. This study asks whether deep-sea stakeholders (primarily scientists) view rare-species research as a priority in guiding environmental management. Delphi methodology (i.e., an iterative survey approach) was used to understand views about whether or not 'deep-sea scientists should allocate more resources to research on rare species in the deep sea, even if this means less resources might be available for abundant-species research.' Results suggest little consensus regarding the prioritization of resources for rare-species research. From Survey 1 to Survey 3, the average participant response shifted toward a view that rare-species research is not a priority if it comes at a cost to research on abundant species. Participants pointed to the need for a balanced approach and highlighted knowledge gaps about even the most fundamental questions, including whether rare species are truly 'rare' or simply under-sampled. Participants emphasized the lack of basic biological knowledge for rare and abundant species, particularly abundant meio- and microscopic species, as well as uncertainty in the roles rare and abundant species play in ecosystem processes. Approaches that jointly consider the role of rare and abundant species in ecosystem functioning (e.g., biological trait analysis) may help to clarify the extent to which rare species need to be incorporated into deep-sea environment management in order to maintain ecosystem functioning.

Distribution of artificial radionuclides in deep sediments of the Mediterranean Sea

International Nuclear Information System (INIS)

Garcia-Orellana, J.; Pates, J.M.; Masque, P.; Bruach, J.M.; Sanchez-Cabeza, J.A.

2009-01-01

Artificial radionuclides enter the Mediterranean Sea mainly through atmospheric deposition following nuclear weapons tests and the Chernobyl accident, but also through the river discharge of nuclear facility effluents. Previous studies of artificial radionuclides impact of the Mediterranean Sea have focussed on shallow, coastal sediments. However, deep sea sediments have the potential to store and accumulate pollutants, including artificial radionuclides. Deep sea marine sediment cores were collected from Mediterranean Sea abyssal plains (depth > 2000 m) and analysed for 239,240 Pu and 137 Cs to elucidate the concentrations, inventories and sources of these radionuclides in the deepest areas of the Mediterranean. The activity - depth profiles of 210 Pb, together with 14 C dating, indicate that sediment mixing redistributes the artificial radionuclides within the first 2.5 cm of the sedimentary column. The excess 210 Pb inventory was used to normalize 239,240 Pu and 137 Cs inventories for variable sediment fluxes. The 239,240 Pu/ 210 Pb xs ratio was uniform across the entire sea, with a mean value of 1.24 x 10 -3 , indicating homogeneous fallout of 239,240 Pu. The 137 Cs/ 210 Pb xs ratio showed differences between the eastern (0.049) and western basins (0.030), clearly significant impact of deep sea sediments from the Chernobyl accident. The inventory ratios of 239,240 Pu/ 137 Cs were 0.041 and 0.025 in the western and eastern basins respectively, greater than the fallout ratio, 0.021, showing more efficient scavenging of 239,240 Pu in the water column and major sedimentation of 137 Cs in the eastern basin. Although areas with water depths of > 2000 m constitute around 40% of the entire Mediterranean basin, the sediments in these regions only contained 2.7% of the 239,240 Pu and 0.95% of the 137 Cs deposited across the Sea in 2000. These data show that the accumulation of artificial radionuclides in deep Mediterranean environments is much lower than predicted by

OPERA goes on camera

CERN Multimedia

2007-01-01

OPERA, the experiment which uses the neutrino beam of CERN’s CNGS facility, has delivered its first neutrino "photos". The core of the detector has been commissioned and has produced images of events resulting from neutrino collisions. The reconstruction of the core (a few cubic millimetres!) of a neutrino interaction at OPERA. The neutrino arriving from the left of the image has interacted with the lead of a brick, producing various particles identifiable by their tracks visible in the emulsion.The snapshot is tiny but it was greeted with enthusiasm by the physicists of OPERA. On 2 October, for the first time, the experiment at the Gran Sasso Laboratory in Italy "photographed" an event produced by the beam of neutrinos sent from CERN, 732 kilometres away. One of the 60,000 photosensitive bricks already installed at the heart of the experiment had produced its first particle track. The commissioning of the OPERA experiment began la...

The Trigger and Data Acquisition System for the KM3NeT-Italy neutrino telescope

Science.gov (United States)

Chiarusi, T.; Favaro, M.; Giacomini, F.; Manzali, M.; Margiotta, A.; Pellegrino, C.

2017-10-01

KM3NeT-Italy is an INFN project that will develop the central part of a submarine cubic-kilometer neutrino telescope in the Ionian Sea, at about 80 km from the Sicilian coast (Italy). It will use hundreds of distributed optical modules to measure the Cherenkov light emitted by high-energy muons, whose signal-to-noise ratio is quite disfavoured. In this contribution the Trigger and Data Acquisition System (TriDAS) developed for the KM3NeT-Italy detector is presented. The “all data to shore” approach is adopted to reduce the complexity of the submarine detector: at the shore station the TriDAS collects, processes and filters all the data coming from the detector, storing triggered events to a permanent storage for subsequent analysis. Due to the large optical background in the sea from 40K decays and bioluminescence, the throughput from the sea can range up to 30 Gbps. This puts strong constraints on the performances of the TriDAS processes and the related network infrastructure.

Search for point-like sources using the diffuse astrophysical muon-neutrino flux in IceCube

Energy Technology Data Exchange (ETDEWEB)

Reimann, Rene; Haack, Christian; Raedel, Leif; Schoenen, Sebastian; Schumacher, Lisa; Wiebusch, Christopher [III. Physikalisches Institut B, RWTH Aachen (Germany); Collaboration: IceCube-Collaboration

2016-07-01

IceCube, a cubic-kilometer sized neutrino detector at the geographic South Pole, has recently confirmed a flux of high-energy astrophysical neutrinos in the track-like muon channel. Although this muon-neutrino flux has now been observed with high significance, no point sources or source classes could be identified yet with these well pointing events. We present a search for point-like sources based on a six year sample of upgoing muon-neutrinos with very low background contamination. To improve the sensitivity, the standard likelihood approach has been modified to focus on the properties of the measured astrophysical muon-neutrino flux.

75 FR 7435 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

Science.gov (United States)

2010-02-19

.... 100105009-0053-01] RIN 0648-AY51 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications AGENCY: National Marine Fisheries Service (NMFS... comments. SUMMARY: NMFS proposes 2010 specifications for the Atlantic deep-sea red crab fishery, including...

Deep Sea Coral National Observation Database, Northeast Region

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The national database of deep sea coral observations. Northeast version 1.0. * This database was developed by the NOAA NOS NCCOS CCMA Biogeography office as part of...

GEOSTAR deep sea floor missions: magnetic data analysis and 1D geo electric structure underneath the Southern Tyrrhenian Sea

International Nuclear Information System (INIS)

Vitale, S.; De Santis, A.; Di Mauro, D.; Cafarella, L.; Palangio, P.; Beranzoli, L.; Favali, P.

2009-01-01

From 2000 to 2005 two geophysical exploration missions were undertaken in the Tyrrenian deep sea floor at depth between -2000 and -3000 m in the framework of the European-funded GEOSTAR Projects. The considered missions in this work are GEOSTAR-2 and ORION-GEOSTAR-3 with the main scientific objective of investigating the deep-sea floor by means of an automatic multiparameter benthic observatory station working continuously from around 5 to 12 months each time. During the two GEOSTAR deep sea floor missions, scalar and vector magnetometers acquired useful magnetic data both to improve global and regional geomagnetic reference models and to infer specific geo electric information about the two sites of magnetic measurements by means of a forward modelling.

First Insights into the Viral Communities of the Deep-sea Anoxic Brines of the Red Sea

KAUST Repository

Antunes, Andre

2015-10-31

The deep-sea brines of the Red Sea include some of the most extreme and unique environments on Earth. They combine high salinities with increases in temperature, heavy metals, hydrostatic pressure, and anoxic conditions, creating unique settings for thriving populations of novel extremophiles. Despite a recent increase of studies focusing on these unusual biotopes, their viral communities remain unexplored. The current survey explores four metagenomic datasets obtained from different brine-seawater interface samples, focusing specifically on the diversity of their viral communities. Data analysis confirmed that the particle-attached viral communities present in the brine-seawater interfaces were diverse and generally dominated by Caudovirales, yet appearing distinct from sample to sample. With a level of caution, we report the unexpected finding of Phycodnaviridae, which infects algae and plants, and trace amounts of insect-infecting Iridoviridae. Results from Kebrit Deep revealed stratification in the viral communities present in the interface: the upper-interface was enriched with viruses associated with typical marine bacteria, while the lower-interface was enriched with haloviruses and halophages. These results provide first insights into the unexplored viral communities present in deep-sea brines of the Red Sea, representing one of the first steps for ongoing and future sampling efforts and studies.

First Insights into the Viral Communities of the Deep-sea Anoxic Brines of the Red Sea

KAUST Repository

Antunes, Andre; Alam, Intikhab; Simoes, Marta; Daniels, Camille Arian; Ferreira, Ari J.S.; Siam, Rania; El-Dorry, Hamza; Bajic, Vladimir B.

2015-01-01

The deep-sea brines of the Red Sea include some of the most extreme and unique environments on Earth. They combine high salinities with increases in temperature, heavy metals, hydrostatic pressure, and anoxic conditions, creating unique settings for thriving populations of novel extremophiles. Despite a recent increase of studies focusing on these unusual biotopes, their viral communities remain unexplored. The current survey explores four metagenomic datasets obtained from different brine-seawater interface samples, focusing specifically on the diversity of their viral communities. Data analysis confirmed that the particle-attached viral communities present in the brine-seawater interfaces were diverse and generally dominated by Caudovirales, yet appearing distinct from sample to sample. With a level of caution, we report the unexpected finding of Phycodnaviridae, which infects algae and plants, and trace amounts of insect-infecting Iridoviridae. Results from Kebrit Deep revealed stratification in the viral communities present in the interface: the upper-interface was enriched with viruses associated with typical marine bacteria, while the lower-interface was enriched with haloviruses and halophages. These results provide first insights into the unexplored viral communities present in deep-sea brines of the Red Sea, representing one of the first steps for ongoing and future sampling efforts and studies.

Decadal trends in deep ocean salinity and regional effects on steric sea level

Science.gov (United States)

Purkey, S. G.; Llovel, W.

2017-12-01

We present deep (below 2000 m) and abyssal (below 4000 m) global ocean salinity trends from the 1990s through the 2010s and assess the role of deep salinity in local and global sea level budgets. Deep salinity trends are assessed using all deep basins with available full-depth, high-quality hydrographic section data that have been occupied two or more times since the 1980s through either the World Ocean Circulation Experiment (WOCE) Hydrographic Program or the Global Ship-Based Hydrographic Investigations Program (GO-SHIP). All salinity data is calibrated to standard seawater and any intercruise offsets applied. While the global mean deep halosteric contribution to sea level rise is close to zero (-0.017 +/- 0.023 mm/yr below 4000 m), there is a large regional variability with the southern deep basins becoming fresher and northern deep basins becoming more saline. This meridional gradient in the deep salinity trend reflects different mechanisms driving the deep salinity variability. The deep Southern Ocean is freshening owing to a recent increased flux of freshwater to the deep ocean. Outside of the Southern Ocean, the deep salinity and temperature changes are tied to isopycnal heave associated with a falling of deep isopycnals in recent decades. Therefore, regions of the ocean with a deep salinity minimum are experiencing both a halosteric contraction with a thermosteric expansion. While the thermosteric expansion is larger in most cases, in some regions the halosteric compensates for as much as 50% of the deep thermal expansion, making a significant contribution to local sea level rise budgets.

Deep-sea disposal: Protecting fish and man

International Nuclear Information System (INIS)

Hagen, A.

1988-01-01

The definition of radioactive waste unsuitable for dumping at sea is based on the protection of man. See IAEA Safety Series No. 78. The development of criteria for assessing the impact on deep sea marine organisms at the population level has been attempted in a report recently published by the IAEA. See IAEA Technical Reports Series, No. 228 (1988). The report indicates that certain radionuclides may give rise to high dose rates to marine organisms if dumping is carried out with the assumptions of instantaneous release at the sea floor and dumping over long periods of time. In the report, a hypothetical dose rate to molluscs from zinc-65, which poses no significant harm to man, has the potential for giving high doses to bottom-dwelling molluscs

Offshore Floating Wind Turbine-driven Deep Sea Water Pumping for Combined Electrical Power and District Cooling

Science.gov (United States)

Sant, T.; Buhagiar, D.; Farrugia, R. N.

2014-06-01

A new concept utilising floating wind turbines to exploit the low temperatures of deep sea water for space cooling in buildings is presented. The approach is based on offshore hydraulic wind turbines pumping pressurised deep sea water to a centralised plant consisting of a hydro-electric power system coupled to a large-scale sea water-cooled air conditioning (AC) unit of an urban district cooling network. In order to investigate the potential advantages of this new concept over conventional technologies, a simplified model for performance simulation of a vapour compression AC unit was applied independently to three different systems, with the AC unit operating with (1) a constant flow of sea surface water, (2) a constant flow of sea water consisting of a mixture of surface sea water and deep sea water delivered by a single offshore hydraulic wind turbine and (3) an intermittent flow of deep sea water pumped by a single offshore hydraulic wind turbine. The analysis was based on one year of wind and ambient temperature data for the Central Mediterranean that is known for its deep waters, warm climate and relatively low wind speeds. The study confirmed that while the present concept is less efficient than conventional turbines utilising grid-connected electrical generators, a significant portion of the losses associated with the hydraulic transmission through the pipeline are offset by the extraction of cool deep sea water which reduces the electricity consumption of urban air-conditioning units.

Offshore Floating Wind Turbine-driven Deep Sea Water Pumping for Combined Electrical Power and District Cooling

International Nuclear Information System (INIS)

Sant, T; Buhagiar, D; Farrugia, R N

2014-01-01

A new concept utilising floating wind turbines to exploit the low temperatures of deep sea water for space cooling in buildings is presented. The approach is based on offshore hydraulic wind turbines pumping pressurised deep sea water to a centralised plant consisting of a hydro-electric power system coupled to a large-scale sea water-cooled air conditioning (AC) unit of an urban district cooling network. In order to investigate the potential advantages of this new concept over conventional technologies, a simplified model for performance simulation of a vapour compression AC unit was applied independently to three different systems, with the AC unit operating with (1) a constant flow of sea surface water, (2) a constant flow of sea water consisting of a mixture of surface sea water and deep sea water delivered by a single offshore hydraulic wind turbine and (3) an intermittent flow of deep sea water pumped by a single offshore hydraulic wind turbine. The analysis was based on one year of wind and ambient temperature data for the Central Mediterranean that is known for its deep waters, warm climate and relatively low wind speeds. The study confirmed that while the present concept is less efficient than conventional turbines utilising grid-connected electrical generators, a significant portion of the losses associated with the hydraulic transmission through the pipeline are offset by the extraction of cool deep sea water which reduces the electricity consumption of urban air-conditioning units

Exploring Archaeal Communities And Genomes Across Five Deep-Sea Brine Lakes Of The Red Sea With A Focus On Methanogens

KAUST Repository

Guan, Yue

2015-12-15

The deep-sea hypersaline lakes in the Red Sea are among the most challenging, extreme, and unusual environments on the planet Earth. Despite their harshness to life, they are inhabited by diverse and novel members of prokaryotes. Methanogenesis was proposed as one of the main metabolic pathways that drive microbial colonization in similar habitats. However, not much is known about the identities of the methane-producing microbes in the Red Sea, let alone the way in which they could adapt to such poly extreme environments. Combining a range of microbial community assessment, cultivation and omics (genomics, transcriptomics, and single amplified genomics) approaches, this dissertation seeks to fill these gaps in our knowledge by studying archaeal composition, particularly methanogens, their genomic capacities and transcriptomic characteristics in order to elucidate their diversity, function, and adaptation to the deep-sea brines of the Red Sea. Although typical methanogens are not abundant in the samples collected from brine pool habitats of the Red Sea, the pilot cultivation experiment has revealed novel halophilic methanogenic species of the domain Archaea. Their physiological traits as well as their genomic and transcriptomic features unveil an interesting genetic and functional adaptive capacity that allows them to thrive in the unique deep-sea hypersaline environments in the Red Sea.

Late Eocene impact events recorded in deep-sea sediments

Science.gov (United States)

Glass, B. P.

1988-01-01

Raup and Sepkoski proposed that mass extinctions have occurred every 26 Myr during the last 250 Myr. In order to explain this 26 Myr periodicity, it was proposed that the mass extinctions were caused by periodic increases in cometary impacts. One method to test this hypothesis is to determine if there were periodic increases in impact events (based on crater ages) that correlate with mass extinctions. A way to test the hypothesis that mass extinctions were caused by periodic increases in impact cratering is to look for evidence of impact events in deep-sea deposits. This method allows direct observation of the temporal relationship between impact events and extinctions as recorded in the sedimentary record. There is evidence in the deep-sea record for two (possibly three) impact events in the late Eocene. The younger event, represented by the North American microtektite layer, is not associated with an Ir anomaly. The older event, defined by the cpx spherule layer, is associated with an Ir anomaly. However, neither of the two impact events recorded in late Eocene deposits appears to be associated with an unusual number of extinctions. Thus there is little evidence in the deep-sea record for an impact-related mass extinction in the late Eocene.

Microplastic pollution in deep-sea sediments

International Nuclear Information System (INIS)

Van Cauwenberghe, Lisbeth; Vanreusel, Ann; Mees, Jan; Janssen, Colin R.

2013-01-01

Microplastics are small plastic particles ( 3 was observed. •The depths from where these microplastics were recovered range from 1176 to 4843 m. •The sizes of the particles range from 75 to 161 μm at their largest cross-section. -- Here, we demonstrate that microplastics have invaded the marine environment to an extent that they appear to even be present in the remote deep sea

The circulation of deep water in the Tasman and Coral seas

International Nuclear Information System (INIS)

Harries, J.R.

1976-07-01

The physical oceanography of the Tasman and Coral Seas is reviewed with an emphasis on the deep currents. There are many uncertainties in the deep circulation pattern. The available data are used to develop an idealised circulation to estimate the likely path taken by water flowing from a depth of 5000 m in the Tasman Sea. The model suggests that the water would finally reach the surface layers south of the Antarctic Convergence with a median delay of 600 years. (author)

Measurement of atmospheric neutrino oscillations and matter effects with PINGU

Energy Technology Data Exchange (ETDEWEB)

Coenders, Stefan; Euler, Sebastian; Krings, Kai; Vehring, Markus; Wallraff, Marius; Wiebusch, Christopher [RWTH Aachen Univ. (Germany). III. Physikalisches Inst.; Collaboration: IceCube-Collaboration

2013-07-01

With IceCube's low-energy extension DeepCore the first significant effects of atmospheric neutrino oscillations have been observed. The planned ''Precision Icecube Next Generation Upgrade'' (PINGU) inside DeepCore will lower the energy threshold to a few GeV, where matter effects of neutrino oscillations have to be taken into account. The Mikheyev-Smirnov-Wolfenstein (MSW) effect modifies the mixing between flavor and mass eigenstates of the neutrinos, resulting in stronger oscillations. Furthermore, neutrinos when passing through the Earth core experience parametric enhancement due to multiple discontinuities in the electron density. In this talk the effects of matter oscillations and the capabilities to measure these effects with PINGU are investigated.

Deep-sea impact experiments and their future requirements

Digital Repository Service at National Institute of Oceanography (India)

Sharma, R.

In recent years, several experiments to assess the potential impacts due to deep-sea mining in the Pacific as well as the Indian Oceans have indicated the immediate changes and restoration patterns of environmental conditions in the marine ecosystem...

An abyssal mobilome: Viruses, plasmids and vesicles from deep-sea hydrothermal vents

OpenAIRE

Lossouarn, Julien; Dupont, Samuel; Gorlas, Aurore; Mercier, Coraline; Bienvenu, Nadege; Marguet, Evelyne; Forterre, Patrick; Geslin, Claire

2015-01-01

Mobile genetic elements (MGEs) such as viruses, plasmids, vesicles, gene transfer agents (GTAs), transposons and transpovirions, which collectively represent the mobilome, interact with cellular organisms from all three domains of life, including those thriving in the most extreme environments. While efforts have been made to better understand deep-sea vent microbial ecology, our knowledge of the mobilome associated with prokaryotes inhabiting deep-sea hydrothermal vents remains limited. Here...

Sudbury neutrino observatory

International Nuclear Information System (INIS)

Ewan, G.T.; Mak, H.B.; Robertson, B.C.

1985-07-01

This report discusses the proposal to construct a unique neutrino observatory. The observatory would contain a Cerenkov detector which would be located 2070 m below the earth's surface in an INCO mine at Creighton near Sudbury and would contain 1000 tons of D20 which is an excellent target material. Neutrinos carry detailed information in their spectra on the reactions taking place deep in the interstellar interior and also provide information on supernova explosions. In addition to their role as astrophysical probes a knowledge of the properties of neutrinos is crucial to theories of grand unification. There are three main objectives of the laboratory. The prime objective will be to study B electron neutrinos from the sun by a direct counting method that will measure their energy and direction. The second major objective will be to establish if electron neutrinos change into other neutrino species in transit from the sun to the earth. Finally it is hoped to be able to observe a supernova with the proposed detector. The features of the Sudbury Neutrino Observatory which make it unique are its high sensitivity to electron neutrinos and its ability to detect all other types of neutrinos of energy greater than 2.2 MeV. In section II of this proposal the major physics objectives are discussed in greater detail. A conceptual design for the detector, and measurements and calculations which establish the feasibility of the neutrino experiments are presented in section III. Section IV is comprised of a discussion on the possible location of the laboratory and Section V contains a brief indication of the main areas to be studied in Phase II of the design study

Ubiquitous healthy diatoms in the deep sea confirm deep carbon injection by the biological pump

KAUST Repository

Agusti, Susana

2015-07-09

The role of the ocean as a sink for CO2 is partially dependent on the downward transport of phytoplankton cells packaged within fast-sinking particles. However, whether such fast-sinking mechanisms deliver fresh organic carbon down to the deep bathypelagic sea and whether this mechanism is prevalent across the ocean requires confirmation. Here we report the ubiquitous presence of healthy photosynthetic cells, dominated by diatoms, down to 4,000 m in the deep dark ocean. Decay experiments with surface phytoplankton suggested that the large proportion (18%) of healthy photosynthetic cells observed, on average, in the dark ocean, requires transport times from a few days to a few weeks, corresponding to sinking rates (124–732 m d−1) comparable to those of fast-sinking aggregates and faecal pellets. These results confirm the expectation that fast-sinking mechanisms inject fresh organic carbon into the deep sea and that this is a prevalent process operating across the global oligotrophic ocean.

Ubiquitous healthy diatoms in the deep sea confirm deep carbon injection by the biological pump

KAUST Repository

Agusti, Susana; Gonzá lez-Gordillo, J. I.; Vaqué , D.; Estrada, M.; Cerezo, M. I.; Salazar, G.; Gasol, J. M.; Duarte, Carlos M.

2015-01-01

The role of the ocean as a sink for CO2 is partially dependent on the downward transport of phytoplankton cells packaged within fast-sinking particles. However, whether such fast-sinking mechanisms deliver fresh organic carbon down to the deep bathypelagic sea and whether this mechanism is prevalent across the ocean requires confirmation. Here we report the ubiquitous presence of healthy photosynthetic cells, dominated by diatoms, down to 4,000 m in the deep dark ocean. Decay experiments with surface phytoplankton suggested that the large proportion (18%) of healthy photosynthetic cells observed, on average, in the dark ocean, requires transport times from a few days to a few weeks, corresponding to sinking rates (124–732 m d−1) comparable to those of fast-sinking aggregates and faecal pellets. These results confirm the expectation that fast-sinking mechanisms inject fresh organic carbon into the deep sea and that this is a prevalent process operating across the global oligotrophic ocean.

Low Energy Neutrino Cross Sections

International Nuclear Information System (INIS)

Zeller, G.P.

2004-01-01

Present atmospheric and accelerator based neutrino oscillation experiments operate at low neutrino energies (Ev ∼ 1 GeV) to access the relevant regions of oscillation parameter space. As such, they require precise knowledge of the cross sections for neutrino-nucleon interactions in the sub-to-few GeV range. At these energies, neutrinos predominantly interact via quasi-elastic (QE) or single pion production processes, which historically have not been as well studied as the deep inelastic scattering reactions that dominate at higher energies.Data on low energy neutrino cross sections come mainly from bubble chamber, spark chamber, and emulsion experiments that collected their data decades ago. Despite relatively poor statistics and large neutrino flux uncertainties, these measurements provide an important and necessary constraint on Monte Carlo models in present use. The following sections discuss the current status of QE, resonant single pion, coherent pion, and single kaon production cross section measurements at low energy

Food web transport of trace metals and radionuclides from the deep sea: a review

International Nuclear Information System (INIS)

Young, J.S.

1979-06-01

This report summarizes aspects of the potential distribution pathways of metals and radionuclides, particularly Co and Ni, through a biological trophic framework after their deposition at 4000 to 5000 meters in the North Atlantic or North Pacific. It discusses (a) the basic, deep-sea trophic structure of eutrophic and oligotrophic regions; (b) the transport pathways of biologically available energy to and from the deep sea, pathways that may act as accumulators and vectors of radionuclide distribution, and (c) distribution routes that have come into question as potential carriers of radionuclides from the deep-sea bed to man

Call to protect deep-sea coral, sponge ecosystems

Science.gov (United States)

Showstack, Randy

2004-03-01

More than 1100 scientists are signatories to a 15 February consensus statement calling for the protection of deep sea coral and sponge ecosystems. The statement indicates that ``the greatest human threat'' to these ecosystems ``is commercial fishing, especially bottom trawling.''

All-flavour Search for Neutrinos from Dark Matter Annihilations in the Milky Way with IceCube/DeepCore

CERN Document Server

INSPIRE-00266703

2016-01-01

We present the first IceCube search for a signal of dark matter annihilations in the Milky Way using all-flavour neutrino-induced particle cascades. The analysis focuses on the DeepCore sub-detector of IceCube, and uses the surrounding IceCube strings as a veto region in order to select starting events in the DeepCore volume. We use 329 live-days of data from IceCube operating in its 86-string configuration during 2011-2012. No neutrino excess is found, the final result being compatible with the background-only hypothesis. From this null result, we derive upper limits on the velocity-averaged self-annihilation cross-section, , for dark matter candidate masses ranging from 30 GeV up to 10 TeV, assuming both a cuspy and a flat-cored dark matter halo profile. For dark matter masses between 200 GeV and 10 TeV, the results improve on all previous IceCube results on , reaching a level of 10^{-23} cm^3 s^-1, depending on the annihilation channel assumed, for a cusped NFW profile. The analysis demonstrates that all-f...

Diversity, abundance and distribution of amoA-encoding archaea in deep-sea methane seep sediments of the Okhotsk Sea.

Science.gov (United States)

Dang, Hongyue; Luan, Xi-Wu; Chen, Ruipeng; Zhang, Xiaoxia; Guo, Lizhong; Klotz, Martin G

2010-06-01

The ecological characteristics of amoA-encoding archaea (AEA) in deep-sea sediments are largely unsolved. This paper aimed to study the diversity, structure, distribution and abundance of the archaeal community and especially its AEA components in the cold seep surface sediments of the Okhotsk Sea, a marginal sea harboring one of the largest methane hydrate reservoirs in the world. Diverse archaeal 16S rRNA gene sequences were identified, with the majority being related to sequences from other cold seep and methane-rich sediment environments. However, the AEA diversity and abundance were quite low as revealed by amoA gene analyses. Correlation analysis indicates that the abundance of the archaeal amoA genes was correlated with the sediment organic matter content. Thus, it is possible that the amoA-carrying archaea here might utilize organic matter for a living. The affiliation of certain archaeal amoA sequences to the GenBank sequences originally obtained from deep-sea hydrothermal vent environments indicated that the related AEA either have a wide range of temperature adaptation or they have a thermophilic evolutionary history in the modern cold deep-sea sediments of the Okhotsk Sea. The dominance of ammonia-oxidizing bacteria over AEA may indicate that bacteria play a significant role in nitrification in the Okhotsk Sea cold seep sediments.

Deep Sea Coral voucher sequence dataset - Identification of deep-sea corals collected during the 2009 - 2014 West Coast Groundfish Bottom Trawl Survey

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Data for this project resides in the West Coast Groundfish Bottom Trawl Survey Database. Deep-sea corals are often components of trawling bycatch, though their...

Microbial gene functions enriched in the Deepwater Horizon deep-sea oil plume

Energy Technology Data Exchange (ETDEWEB)

Lu, Z.; Deng, Y.; Nostrand, J.D. Van; He, Z.; Voordeckers, J.; Zhou, A.; Lee, Y.-J.; Mason, O.U.; Dubinsky, E.; Chavarria, K.; Tom, L.; Fortney, J.; Lamendella, R.; Jansson, J.K.; D?haeseleer, P.; Hazen, T.C.; Zhou, J.

2011-06-15

The Deepwater Horizon oil spill in the Gulf of Mexico is the deepest and largest offshore spill in U.S. history and its impacts on marine ecosystems are largely unknown. Here, we showed that the microbial community functional composition and structure were dramatically altered in a deep-sea oil plume resulting from the spill. A variety of metabolic genes involved in both aerobic and anaerobic hydrocarbon degradation were highly enriched in the plume compared to outside the plume, indicating a great potential for intrinsic bioremediation or natural attenuation in the deep-sea. Various other microbial functional genes relevant to carbon, nitrogen, phosphorus, sulfur and iron cycling, metal resistance, and bacteriophage replication were also enriched in the plume. Together, these results suggest that the indigenous marine microbial communities could play a significant role in biodegradation of oil spills in deep-sea environments.

First results of the Instrumentation Line for the deep-sea ANTARES neutrino telescope

Science.gov (United States)

Aguilar, J. A.; Albert, A.; Ameli, F.; Anghinolfi, M.; Anton, G.; Anvar, S.; Aslanides, E.; Aubert, J.-J.; Barbarito, E.; Basa, S.; Battaglieri, M.; Becherini, Y.; Bellotti, R.; Beltramelli, J.; Bertin, V.; Bigi, A.; Billault, M.; Blaes, R.; de Botton, N.; Bouwhuis, M. C.; Bradbury, S. M.; Bruijn, R.; Brunner, J.; Burgio, G. F.; Busto, J.; Cafagna, F.; Caillat, L.; Calzas, A.; Capone, A.; Caponetto, L.; Carmona, E.; Carr, J.; Cartwright, S. L.; Castel, D.; Castorina, E.; Cavasinni, V.; Cecchini, S.; Ceres, A.; Charvis, P.; Chauchot, P.; Chiarusi, T.; Circella, M.; Colnard, C.; Compère, C.; Coniglione, R.; Cottini, N.; Coyle, P.; Cuneo, S.; Cussatlegras, A.-S.; Damy, G.; van Dantzig, R.; De Marzo, C.; Dekeyser, I.; Delagnes, E.; Denans, D.; Deschamps, A.; Dessages-Ardellier, F.; Destelle, J.-J.; Dinkespieler, B.; Distefano, C.; Donzaud, C.; Drogou, J.-F.; Druillole, F.; Durand, D.; Ernenwein, J.-P.; Escoffier, S.; Falchini, E.; Favard, S.; Feinstein, F.; Ferry, S.; Festy, D.; Fiorello, C.; Flaminio, V.; Galeotti, S.; Gallone, J.-M.; Giacomelli, G.; Girard, N.; Gojak, C.; Goret, Ph.; Graf, K.; Hallewell, G.; Harakeh, M. N.; Hartmann, B.; Heijboer, A.; Heine, E.; Hello, Y.; Hernández-Rey, J. J.; Hößl, J.; Hoffman, C.; Hogenbirk, J.; Hubbard, J. R.; Jaquet, M.; Jaspers, M.; de Jong, M.; Jouvenot, F.; Kalantar-Nayestanaki, N.; Kappes, A.; Karg, T.; Karkar, S.; Katz, U.; Keller, P.; Kok, H.; Kooijman, P.; Kopper, C.; Korolkova, E. V.; Kouchner, A.; Kretschmer, W.; Kruijer, A.; Kuch, S.; Kudryavstev, V. A.; Lachartre, D.; Lafoux, H.; Lagier, P.; Lahmann, R.; Lamanna, G.; Lamare, P.; Languillat, J. C.; Laschinsky, H.; Le Guen, Y.; Le Provost, H.; Le Van Suu, A.; Legou, T.; Lim, G.; Lo Nigro, L.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Louis, F.; Lucarelli, F.; Lyashuk, V.; Marcelin, M.; Margiotta, A.; Masullo, R.; Mazéas, F.; Mazure, A.; McMillan, J. E.; Megna, R.; Melissas, M.; Migneco, E.; Milovanovic, A.; Mongelli, M.; Montaruli, T.; Morganti, M.; Moscoso, L.; Musumeci, M.; Naumann, C.; Naumann-Godo, M.; Niess, V.; Olivetto, C.; Ostasch, R.; Palanque-Delabrouille, N.; Payre, P.; Peek, H.; Petta, C.; Piattelli, P.; Pineau, J.-P.; Poinsignon, J.; Popa, V.; Pradier, T.; Racca, C.; Randazzo, N.; van Randwijk, J.; Real, D.; van Rens, B.; Réthoré, F.; Rewiersma, P.; Riccobene, G.; Rigaud, V.; Ripani, M.; Roca, V.; Roda, C.; Rolin, J. F.; Romita, M.; Rose, H. J.; Rostovtsev, A.; Roux, J.; Ruppi, M.; Russo, G. V.; Salesa, F.; Salomon, K.; Sapienza, P.; Schmitt, F.; Schuller, J.-P.; Shanidze, R.; Sokalski, I.; Spona, T.; Spurio, M.; van der Steenhoven, G.; Stolarczyk, T.; Streeb, K.; Stubert, D.; Sulak, L.; Taiuti, M.; Tamburini, C.; Tao, C.; Terreni, G.; Thompson, L. F.; Valdy, P.; Valente, V.; Vallage, B.; Venekamp, G.; Verlaat, B.; Vernin, P.; de Vita, R.; de Vries, G.; van Wijk, R.; de Witt Huberts, P.; Wobbe, G.; de Wolf, E.; Yao, A.-F.; Zaborov, D.; Zaccone, H.; Zornoza, J. D.; Zúñiga, J.

2006-11-01

In 2005, the ANTARES Collaboration deployed and operated at a depth of 2500 m a so-called Mini Instrumentation Line equipped with Optical Modules (MILOM) at the ANTARES site. The various data acquired during the continuous operation from April to December 2005 of the MILOM confirm the satisfactory performance of the Optical Modules, their front-end electronics and readout system, as well as the calibration devices of the detector. The in situ measurement of the Optical Module time response yields a resolution better than 0.5 ns. The performance of the acoustic positioning system, which enables the spatial reconstruction of the ANTARES detector with a precision of about 10 cm, is verified. These results demonstrate that with the full ANTARES neutrino telescope the design angular resolution of better than 0.3° can be realistically achieved.

THE US LONG BASELINE NEUTRINO EXPERIMENT STUDY.

Energy Technology Data Exchange (ETDEWEB)

BISHAI,M.

2007-08-06

The US Long Baseline Neutrino Experiment Study was commissioned jointly by Brookhaven National Laboratory (BNL)and Fermi National Accelerator Laboratory (FNAL) to investigate the potential for future U.S. based long baseline neutrino oscillation experiments using MW class conventional neutrino beams that can be produced at FNAL. The experimental baselines are based on two possible detector locations: (1) off-axis to the existing FNAL NuMI beamline at baselines of 700 to 810 km and (2) NSF's proposed future Deep Underground Science and Engineering Laboratory (DUSEL) at baselines greater than 1000km. Two detector technologies are considered: a megaton class Water Cherenkov detector deployed deep underground at a DUSEL site, or a 100kT Liquid Argon Time-Projection Chamber (TPC) deployed on the surface at any of the proposed sites. The physics sensitivities of the proposed experiments are summarized. We find that conventional horn focused wide-band neutrino beam options from FNAL aimed at a massive detector with a baseline of > 1000km have the best sensitivity to CP violation and the neutrino mass hierarchy for values of the mixing angle {theta}{sub 13} down to 2{sup o}.

First Insights into the Viral Communities of the Deep-sea Anoxic Brines of the Red Sea.

Science.gov (United States)

Antunes, André; Alam, Intikhab; Simões, Marta Filipa; Daniels, Camille; Ferreira, Ari J S; Siam, Rania; El-Dorry, Hamza; Bajic, Vladimir B

2015-10-01

The deep-sea brines of the Red Sea include some of the most extreme and unique environments on Earth. They combine high salinities with increases in temperature, heavy metals, hydrostatic pressure, and anoxic conditions, creating unique settings for thriving populations of novel extremophiles. Despite a recent increase of studies focusing on these unusual biotopes, their viral communities remain unexplored. The current survey explores four metagenomic datasets obtained from different brine-seawater interface samples, focusing specifically on the diversity of their viral communities. Data analysis confirmed that the particle-attached viral communities present in the brine-seawater interfaces were diverse and generally dominated by Caudovirales, yet appearing distinct from sample to sample. With a level of caution, we report the unexpected finding of Phycodnaviridae, which infects algae and plants, and trace amounts of insect-infecting Iridoviridae. Results from Kebrit Deep revealed stratification in the viral communities present in the interface: the upper-interface was enriched with viruses associated with typical marine bacteria, while the lower-interface was enriched with haloviruses and halophages. These results provide first insights into the unexplored viral communities present in deep-sea brines of the Red Sea, representing one of the first steps for ongoing and future sampling efforts and studies. Copyright © 2015 The Authors. Production and hosting by Elsevier Ltd.. All rights reserved.

Deep-sea fungi as a source of alkaline and cold-tolerant proteases

Digital Repository Service at National Institute of Oceanography (India)

Damare, S.R.; Raghukumar, C.; Muraleedharan, U.; Raghukumar, S.

,5]. Fungi and their enzymes from the deep-sea environment have received scant attention. Proteins and peptides constitute a substantial portion of the organic nutrients present in the deep-sea sediments as well as suspended particulate matter [6... alkaline protease using a qualitative plate assay on Czapek Dox agar (CDA) supplemented with 1% skimmed milk powder (Trade name Sagar, India). Clearance zone produced around the fungal colonies in plates indicated protease positive reaction [19...

Exponential Decline of Deep-Sea Ecosystem Functioning Linked to Benthic Biodiversity Loss

OpenAIRE

Danovaro, Roberto; Gambi, Cristina; Dell'Anno, Antonio; Corinaldesi, Cinzia; Fraschetti, Simonetta; Vanreusel, Ann; Vincx, Magda; Gooday, Andrew J.

2008-01-01

BackgroundRecent investigations suggest that biodiversity loss might impair the functioning and sustainability of ecosystems. Although deep-sea ecosystems are the most extensive on Earth, represent the largest reservoir of biomass, and host a large proportion of undiscovered biodiversity, the data needed to evaluate the consequences of biodiversity loss on the ocean floor are completely lacking.ResultsHere, we present a global-scale study based on 116 deep-sea sites that relates benthic biodi...

Research on the usage of a deep sea fast reactor

Energy Technology Data Exchange (ETDEWEB)

Otsubo, Akira; Kowata, Yasuki [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

1997-09-01

Many new types of fast reactors have been studied in PNC. A deep sea fast reactor has the highest realization probability of the reactors studied because its development is desired by many specialists of oceanography, meteorology, deep sea bottom oil field, seismology and so on and because the development does not cost big budget and few technical problems remain to be solved. This report explains the outline and the usage of the reactor of 40 kWe and 200 to 400 kWe. The reactor can be used as a power source at an unmanned base for long term climate prediction and the earth science and an oil production base in a deep sea region. On the other hand, it is used for heat and electric power supply to a laboratory in the polar region. In future, it will be used in the space. At the present time, a large FBR development plan does not proceed successfully and a realization goal time of FBR has gone later and later. We think that it is the most important to develop the reactor as fast as possible and to plant a fast reactor technique in our present society. (author)

Predictive modeling of deep-sea fish distribution in the Azores

Science.gov (United States)

Parra, Hugo E.; Pham, Christopher K.; Menezes, Gui M.; Rosa, Alexandra; Tempera, Fernando; Morato, Telmo

2017-11-01

Understanding the link between fish and their habitat is essential for an ecosystem approach to fisheries management. However, determining such relationship is challenging, especially for deep-sea species. In this study, we applied generalized additive models (GAMs) to relate presence-absence and relative abundance data of eight economically-important fish species to environmental variables (depth, slope, aspect, substrate type, bottom temperature, salinity and oxygen saturation). We combined 13 years of catch data collected from systematic longline surveys performed across the region. Overall, presence-absence GAMs performed better than abundance models and predictions made for the observed data successfully predicted the occurrence of the eight deep-sea fish species. Depth was the most influential predictor of all fish species occurrence and abundance distributions, whereas other factors were found to be significant for some species but did not show such a clear influence. Our results predicted that despite the extensive Azores EEZ, the habitats available for the studied deep-sea fish species are highly limited and patchy, restricted to seamounts slopes and summits, offshore banks and island slopes. Despite some identified limitations, our GAMs provide an improved knowledge of the spatial distribution of these commercially important fish species in the region.

Neutrino sunshine

International Nuclear Information System (INIS)

Anon.

1993-01-01

Full text: On 10 June 1992, at the Neutrino 92 meeting in Grenada, Spain, Till Kirsten of Heidelberg's Max Planck Institute reported that neutrinos from sunshine had been seen. Most of the energy pumped out by the Sun comes from the fusion of protons into alpha particles, a process which also liberates neutrinos. While it takes about a million years for radiant energy formed in the deep interior of the Sun to fight its way to the surface, the highly penetrating neutrinos emerge almost immediately. It was in 1970 that Ray Davis and his team began taking data with a tank containing 615 tons of perchloroethylene (dry cleaning fluid) 1500 metres underground in the Homestake gold mine, South Dakota. The observed signal is consistently smaller than what is expected. This 'solar neutrino problem' was confirmed by the Kamioka mine experiment in Japan, looking at the Cherenkov light released by neutrino interactions in some 700 tons of water. However these experiments are only sensitive to a tiny high energy tail of the solar neutrino spectrum, and to understand what is going on needs measurements of the primary neutrinos from proton fusion. To get at these neutrinos, two large new detectors, using gallium and sensitive to these lower energy particles, have been built and commissioned in the past few years. The detectors are SAGE ('Soviet' American Gallium Experiment) in the Baksan Neutrino Observatory in the Caucasus, and Gallex, a team from France, Germany, Israel, Italy and the US in the Italian Gran Sasso underground Laboratory. At Grenada, Kirsten reported unmistakable signs of solar neutrinos of proton origin recorded in Gallex. SAGE and Gallex do not yet have enough data to unambiguously fix the level of primary solar neutrinos reaching the Earth, and the interpretation of the interim results tends to be subjective. However after 23 years of conditioning through watching the solar neutrinos' high energy tail, the prospect of a neutrino

Dirac Sea and its Evolution

Science.gov (United States)

Volfson, Boris

2013-09-01

The hypothesis of transition from a chaotic Dirac Sea, via highly unstable positronium, into a Simhony Model of stable face-centered cubic lattice structure of electrons and positrons securely bound in vacuum space, is considered. 13.75 Billion years ago, the new lattice, which, unlike a Dirac Sea, is permeable by photons and phonons, made the Universe detectable. Many electrons and positrons ended up annihilating each other producing energy quanta and neutrino-antineutrino pairs. The weak force of the electron-positron crystal lattice, bombarded by the chirality-changing neutrinos, may have started capturing these neutrinos thus transforming from cubic crystals into a quasicrystal lattice. Unlike cubic crystal lattice, clusters of quasicrystals are "slippery" allowing the formation of centers of local torsion, where gravity condenses matter into galaxies, stars and planets. In the presence of quanta, in a quasicrystal lattice, the Majorana neutrinos' rotation flips to the opposite direction causing natural transformations in a category comprised of three components; two others being positron and electron. In other words, each particle-antiparticle pair "e-" and "e+", in an individual crystal unit, could become either a quasi- component "e- ve e+", or a quasi- component "e+ - ve e-". Five-to-six six billion years ago, a continuous stimulation of the quasicrystal aetherial lattice by the same, similar, or different, astronomical events, could have triggered Hebbian and anti-Hebbian learning processes. The Universe may have started writing script into its own aether in a code most appropriate for the quasicrystal aether "hardware": Eight three-dimensional "alphabet" characters, each corresponding to the individual quasi-crystal unit shape. They could be expressed as quantum Turing machine qubits, or, alternatively, in a binary code. The code numerals could contain terminal and nonterminal symbols of the Chomsky's hierarchy, wherein, the showers of quanta, forming the

Chronicles of the deep : ageing deep-sea corals in New Zealand waters

International Nuclear Information System (INIS)

Tracey, D.; Neil, H.; Gordon, D.; O'Shea, S.

2003-01-01

How old is a coral? Finding the answer requires some rather complex steps. We need to understand: the source of carbonate; the effects of climatic events; how to interpret growth zones; the effect of 14 C and biological processes such as feeding and reproduction; and how to overcome the lack of deep-sea environmental data records. We also need to find out where on the coral we should be sampling to get the best estimates of age. At the moment we know little about how deep-sea corals deposit their calcite, but we will be exploring this further so that we can have greater confidence in our age estimates. To confirm and validate age and growth, it will be necessary to use a combination of some of the the possible methods for ageing coral. In addition to ageing the corals, this work should yield a high-resolution record of ocean temperature during the past 100 years by using stable-isotope signatures preserved in the corals' carbonate skeletons. (author). 4 figs

Deep-Sea Trench Microbiology Down to 10.9 Kilometers Below the Surface

Science.gov (United States)

Bartlett, D. H.

2012-12-01

Deep-sea trenches, extending to more than 10.9 km below the sea surface, are among the most remote and infrequently sampled habitats. As a result a global perspective of microbial diversity and adaptation is lacking in these extreme settings. I will present the results of studies of deep-sea trench microbes collected in the Puerto Rico Trench (PRT), Tonga Trench, New Britain Trench and Mariana Trench. The samples collected include sediment, seawater and animals in baited traps. The analyses to be described include microbial community activity and viability measurements as a function of hydrostatic pressure, microbial culturing at high pressure under various physiological conditions, phylogenetics and metagenome and single-cell genome characterizations. Most of the results to date stem from samples recovered from the PRT. The deep-sea PRT Trench microbes have more in common at the species level with other deep-sea microbial communities previously characterized in the Pacific Ocean and the Mediterranean Sea than with the microbial populations above them in shallow waters. They also harbor larger genomes with more genes assigned to signal transduction, transcription, replication, recombination and repair and inorganic ion transport. The overrepresented transporters in the PRT metagenome include di- and tri-carboxylate transporters that correspond to the prevailing catabolic processes such as butanoate, glyoxylate and dicarboxylate metabolism. A surprisingly high abundance of sulfatases for the degradation of sulfated polysaccharides were also present in the PRT. But, perhaps the most dramatic adaptational feature of the PRT microbes is heavy metal resistance, as reflected in the high numbers of metal efflux systems present. Single-cell genomics approaches have proven particularly useful for placing PRT metagenomic data into context.

PINGU sensitivity to neutrino mass hierarchy

International Nuclear Information System (INIS)

Groß, Andreas

2014-01-01

Determination of the neutrino mass hierarchy (NMH) is among the most fundamental questions in particle physics. Recent measurements of 1) a large mixing angle between the first and the third neutrino mass eigenstates and 2) the first observation of atmospheric neutrino oscillations at tens of GeV with neutrino telescopes, open the intriguing new possibility to exploit matter effects in neutrino oscillation to determine the neutrino mass hierarchy. A further extension of IceCube/DeepCore called PINGU (Precision IceCube Next Generation Upgrade) has been recently envisioned with the ultimate goal to measure neutrino mass hierarchy. PINGU would consist of additional IceCube-like strings of detectors deployed in the deepest and cleanest ice in the center of IceCube. More densely deployed instrumentation would provide a threshold substantially below 10 GeV and enhance the sensitivity to the mass hierarchy signal in atmospheric neutrinos. Here we discuss an estimate of the PINGU sensitivity to the mass hierarchy determined using an approximation with an Asimov dataset and an oscillation parameter fit

Monitoring the sedimentary carbon in an artificially disturbed deep-sea sedimentary environment

Digital Repository Service at National Institute of Oceanography (India)

Nath, B.N.; Khadge, N.H.; Nabar, S.; Raghukumar, C.; Ingole, B.S.; Valsangkar, A.B.; Sharma, R.; Srinivas, K.

1 Author version: Environ. Monit. Assess., vol.184; 2012; 2829-2844 Monitoring the sedimentary carbon in an artificially disturbed deep-sea sedimentary environment B. Nagender Nath * , N.H. Khadge, Sapana Nabar, C. Raghu Kumar, B.S. Ingole... community two years after an artificial rapid deposition event. Publication of Seto Marine Biological Laboratory, 39(1), 17-27. Gage, J.D. (1978). Animals in deep-sea sediments. Proceedings of Royal Society of Edinburgh, 768, 77-93. Gage, J.D., & Tyler...

Structure, functioning, and cumulative stressors of Mediterranean deep-sea ecosystems

OpenAIRE

Tecchio, S.; Coll, Marta; Sarda, F.

2015-01-01

Environmental stressors, such as climate fluctuations, and anthropogenic stressors, such as fishing, are of major concern for the management of deep-sea ecosystems. Deep-water habitats are limited by primary productivity and are mainly dependent on the vertical input of organic matter from the surface. Global change over the latest decades is imparting variations in primary productivity levels across oceans, and thus it has an impact on the amount of organic matter landing on the deep seafloo...

Monsoon control on trace metal fluxes in the deep Arabian Sea

Indian Academy of Sciences (India)

Monsoon control on trace metal fluxes in the deep Arabian Sea ... at marine boundaries and surface ocean processes: Forcings and feedbacks Volume 115 ... Annual Al fluxes at shallow and deep trap depths were 0.47 and 0.46 gm−2 in the ...

A comparative experimental approach to ecotoxicology in shallow-water and deep-sea holothurians suggests similar behavioural responses.

Science.gov (United States)

Brown, Alastair; Wright, Roseanna; Mevenkamp, Lisa; Hauton, Chris

2017-10-01

Exploration of deep-sea mineral resources is burgeoning, raising concerns regarding ecotoxicological impacts on deep-sea fauna. Assessing toxicity in deep-sea species is technologically challenging, which promotes interest in establishing shallow-water ecotoxicological proxy species. However, the effects of temperature and hydrostatic pressure on toxicity, and how adaptation to deep-sea environmental conditions might moderate these effects, are unknown. To address these uncertainties we assessed behavioural and physiological (antioxidant enzyme activity) responses to exposure to copper-spiked artificial sediments in a laboratory experiment using a shallow-water holothurian (Holothuria forskali), and in an in situ experiment using a deep-sea holothurian (Amperima sp.). Both species demonstrated sustained avoidance behaviour, evading contact with contaminated artificial sediment. However, A. sp. demonstrated sustained avoidance of 5mgl -1 copper-contaminated artificial sediment whereas H. forskali demonstrated only temporary avoidance of 5mgl -1 copper-contaminated artificial sediment, suggesting that H. forskali may be more tolerant of metal exposure over 96h. Nonetheless, the acute behavioural response appears consistent between the shallow-water species and the deep-sea species, suggesting that H. forskali may be a suitable ecotoxicological proxy for A. sp. in acute (≤24h) exposures, which may be representative of deep-sea mining impacts. No antioxidant response was observed in either species, which was interpreted to be the consequence of avoiding copper exposure. Although these data suggest that shallow-water taxa may be suitable ecotoxicological proxies for deep-sea taxa, differences in methodological and analytical approaches, and in sex and reproductive stage of experimental subjects, require caution in assessing the suitability of H. forskali as an ecotoxicological proxy for A. sp. Nonetheless, avoidance behaviour may have bioenergetic consequences that

Biogeography of Persephonella in deep-sea hydrothermal vents of the Western Pacific.

Directory of Open Access Journals (Sweden)

Sayaka eMino

2013-04-01

Full Text Available Deep-sea hydrothermal vent fields are areas on the seafloor with high biological productivity fueled by microbial chemosynthesis. Members of the Aquificales genus Persephonella are obligately chemosynthetic bacteria, and appear to be key players in carbon, sulfur, and nitrogen cycles in high temperature habitats at deep-sea vents. Although this group of bacteria has cosmopolitan distribution in deep-sea hydrothermal ecosystem around the world, little is known about their population structure such as intraspecific genomic diversity, distribution pattern, and phenotypic diversity. We developed the multi-locus sequence analysis (MLSA scheme for their genomic characterization. Sequence variation was determined in five housekeeping genes and one functional gene of 36 P. hydrogeniphila strains originated from the Okinawa Trough and the South Mariana Trough. Although the strains share > 98.7% similarities in 16S rRNA gene sequences, MLSA revealed 35 different sequence types, indicating their extensive genomic diversity. A phylogenetic tree inferred from all concatenated gene sequences revealed the clustering of isolates according to the geographic origin. In addition, the phenotypic clustering pattern inferred from whole-cell matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS analysis can be correlated to their MLSA clustering pattern. This study represents the first MLSA combined with phenotypic analysis indicative of allopatric speciation of deep-sea hydrothermal vent bacteria.

A short history of neutrinos, what we have learned about them, what we have learned using them, up to neutrino oscillations.”

CERN Multimedia

CERN. Geneva

2012-01-01

This, the opening talk of the Kyoto conference, Neutrino 2012, attempts a brief review of the history of the neutrinos, up to neutrino oscillations, beginning with the discovery of the continuous β spectrum in 1914, to the demonstration of the tau neutrino in 2001, the contributions of the study of neutrino interactions to the evolution of the electroweak and the QCD theories, in particular the discovery of neutral currents, the demonstrations that the partons of nuclear structure are quarks, and the first quantitative confirmation of QCD in the scaling violations of deep inelastic scattering, and the structure functions of the nucleon.

Global latitudinal species diversity gradient in deep-sea benthic foraminifera

Science.gov (United States)

Culver, Stephen J.; Buzas, Martin A.

2000-02-01

Global scale patterns of species diversity for modern deep-sea benthic foraminifera, an important component of the bathyal and abyssal meiofauna, are examined using comparable data from five studies in the Atlantic, ranging over 138° of latitude from the Norwegian Sea to the Weddell Sea. We show that a pattern of decreasing diversity with increasing latitude characterises both the North and South Atlantic. This pattern is confirmed for the northern hemisphere by independent data from the west-central North Atlantic and the Arctic basin. Species diversity in the North Atlantic northwards from the equator is variable until a sharp fall in the Norwegian Sea (ca. 65°N). In the South Atlantic species diversity drops from a maximum in latitudes less than 30°S and then decreases slightly from 40 to 70°S. For any given latitude, North Atlantic diversity is generally lower than in the South Atlantic. Both ecological and historical factors related to food supply are invoked to explain the formation and maintenance of the latitudinal gradient of deep-sea benthic foraminiferal species diversity. The gradient formed some 36 million years ago when global climatic cooling led to seasonally fluctuating food supply in higher latitudes.

Bacterial diversity and biogeography in deep-sea sediments of the South Atlantic Ocean

DEFF Research Database (Denmark)

Schauer, Regina; Bienhold, Christina; Ramette, Alban

2010-01-01

in 1051 sequences. Phylotypes affiliated with Gammaproteobacteria, Deltaproteobacteria and Acidobacteria were present in all three basins. The distribution of these shared phylotypes seemed to be influenced neither by the Walvis Ridge nor by different deep water masses, suggesting a high dispersal......Microbial biogeographic patterns in the deep sea depend on the ability of microorganisms to disperse. One possible limitation to microbial dispersal may be the Walvis Ridge that separates the Antarctic Lower Circumpolar Deep Water from the North Atlantic Deep Water. We examined bacterial...... communities in three basins of the eastern South Atlantic Ocean to determine diversity and biogeography of bacterial communities in deep-sea surface sediments. The analysis of 16S ribosomal RNA (rRNA) gene clone libraries in each basin revealed a high diversity, representing 521 phylotypes with 98% identity...

Potential contribution of surface-dwelling Sargassum algae to deep-sea ecosystems in the southern North Atlantic

Science.gov (United States)

Baker, Philip; Minzlaff, Ulrike; Schoenle, Alexandra; Schwabe, Enrico; Hohlfeld, Manon; Jeuck, Alexandra; Brenke, Nils; Prausse, Dennis; Rothenbeck, Marcel; Brix, Saskia; Frutos, Inmaculada; Jörger, Katharina M.; Neusser, Timea P.; Koppelmann, Rolf; Devey, Colin; Brandt, Angelika; Arndt, Hartmut

2018-02-01

Deep-sea ecosystems, limited by their inability to use primary production as a source of carbon, rely on other sources to maintain life. Sedimentation of organic carbon into the deep sea has been previously studied, however, the high biomass of sedimented Sargassum algae discovered during the VEMA Transit expedition in 2014/2015 to the southern North Atlantic, and its potential as a regular carbon input, has been an underestimated phenomenon. To determine the potential for this carbon flux, a literature survey of previous studies that estimated the abundance of surface water Sargassum was conducted. We compared these estimates with quantitative analyses of sedimented Sargassum appearing on photos taken with an autonomous underwater vehicle (AUV) directly above the abyssal sediment during the expedition. Organismal communities associated to Sargassum fluitans from surface waters were investigated and Sargassum samples collected from surface waters and the deep sea were biochemically analyzed (fatty acids, stable isotopes, C:N ratios) to determine degradation potential and the trophic significance within deep-sea communities. The estimated Sargassum biomass (fresh weight) in the deep sea (0.07-3.75 g/m2) was several times higher than that estimated from surface waters in the North Atlantic (0.024-0.84 g/m2). Biochemical analysis showed degradation of Sargassum occurring during sedimentation or in the deep sea, however, fatty acid and stable isotope analysis did not indicate direct trophic interactions between the algae and benthic organisms. Thus, it is assumed that components of the deep-sea microbial food web form an important link between the macroalgae and larger benthic organisms. Evaluation of the epifauna showed a diverse nano- micro-, meio, and macrofauna on surface Sargassum and maybe transported across the Atlantic, but we had no evidence for a vertical exchange of fauna components. The large-scale sedimentation of Sargassum forms an important trophic link

RECENT DEVELOPMENTS IN ULTRA-HIGH ENERGY NEUTRINO ASTRONOMY

Directory of Open Access Journals (Sweden)

Peter K. F. Grieder

2013-12-01

Full Text Available We outline the current situation in ultrahigh energy (UHE cosmic ray physics, pointing out the remaining problems, in particular the puzzle concerning the origin of the primary radiation and the role of neutrino astronomy for locating the sources. Various methods for the detection of UHE neutrinos are briefly described and their merits compared. We give an account of the achievements of the existing optical Cherenkov neutrino telescopes, outline the possibility of using air fluorescence and particle properties of air showers to identify neutrino induced events, and discuss various pioneering experiments employing radio and acoustic detection of extremely energetic neutrinos. The next generation of space, ground and sea based neutrino telescopes now under construction or in the planning phase are listed.

Ion transport in deep-sea sediments

International Nuclear Information System (INIS)

Heath, G.R.

1979-01-01

Initial assessment of the ability of deep-sea clays to contain nuclear waste is optimistic. Yet, the investigators have no delusions about the complexity of the natural geochemical system and the perturbations that may result from emplacement of thermally-hot waste cannisters. Even though they may never be able to predict the exact nature of all these perturbations, containment of the nuclides by the waste form/cannister system until most of the heat has decayed, and burial of the waste to a sufficient depth that the altered zone can be treated as a black box source of dissolved nuclides to the enclosing unperturbed sediment, encourage them to believe that ion migration in the deep seabed can be modeled accurately and that our preliminary estimates of migration rates are likely to be reasonably realistic

Flavor distributions in the nucleons: SU(2) sea asymmetry or isospin symmetry breaking?

International Nuclear Information System (INIS)

Ma, B.; Schaefer, A.; Greiner, W.

1993-01-01

The Gottfried sum-rule violation reported by the New Muon Collaboration was interpreted as an indication for a flavor asymmetry of the sea quark in the nucleon. We investigate the alternative possibility that isospin symmetry between the proton and the neutron is breaking for small x. We examine systematically the consequences of this possibility for several processes, namely, neutrino deep inelastic scattering, the charged pion Drell-Yan process, the proton Drell-Yan process, and semi-inclusive deep inelastic scattering, and conclude that a decision between the two alternative explanations is possible

Shelf erosion and submarine river canyons: implications for deep-sea oxygenation and ocean productivity during glaciation

Directory of Open Access Journals (Sweden)

I. Tsandev

2010-06-01

Full Text Available The areal exposure of continental shelves during glacial sea level lowering enhanced the transfer of erodible reactive organic matter to the open ocean. Sea level fall also activated submarine canyons thereby allowing large rivers to deposit their particulate load, via gravity flows, directly in the deep-sea. Here, we analyze the effects of shelf erosion and particulate matter re-routing to the open ocean during interglacial to glacial transitions, using a coupled model of the marine phosphorus, organic carbon and oxygen cycles. The results indicate that shelf erosion and submarine canyon formation may significantly lower deep-sea oxygen levels, by up to 25%, during sea level low stands, mainly due to the supply of new material from the shelves, and to a lesser extent due to particulate organic matter bypassing the coastal zone. Our simulations imply that deep-sea oxygen levels can drop significantly if eroded shelf material is deposited to the seafloor. Thus the glacial ocean's oxygen content could have been significantly lower than during interglacial stages. Primary production, organic carbon burial and dissolved phosphorus inventories are all affected by the erosion and rerouting mechanisms. However, re-routing of the continental and eroded shelf material to the deep-sea has the effect of decoupling deep-sea oxygen demand from primary productivity in the open ocean. P burial is also not affected showing a disconnection between the biogeochemical cycles in the water column and the P burial record.

Selected results from the ANTARES neutrino telescope

International Nuclear Information System (INIS)

Bouhou, B.

2014-01-01

ANTARES uses sea water as as a detection medium to observe cosmic neutrinos. The ANTARES neutrino telescope is taking data with its complete configuration since 2008. Its main goal is the detection of cosmic neutrinos from the Southern hemisphere sky, coming from Galactic and extragalactic sources. Recently, the ANTARES collaboration has published many results from data collected from 2007 to 2010 using detector configurations containing between 5 to 12 detection strings. Among those, search of point sources and diffuse flux from high energy cosmic neutrinos, both resulted in stringent and competitive upper limits for the flux of cosmic neutrinos. In addition, ANTARES is involved in multi-messenger projects looking for correlations between neutrinos and gamma rays or gravitational wave emitted by sources like Gamma-Ray bursts. In this paper we report on some recent results published by the ANTARES collaboration

Advancing Astrophysics with the Square Kilometre Array

CERN Document Server

Fender, Rob; Govoni, Federica; Green, Jimi; Hoare, Melvin; Jarvis, Matt; Johnston-Hollitt, Melanie; Keane, Evan; Koopmans, Leon; Kramer, Michael; Maartens, Roy; Macquart, Jean-Pierre; Mellema, Garrelt; Oosterloo, Tom; Prandoni, Isabella; Pritchard, Jonathan; Santos, Mario; Seymour, Nick; Stappers, Ben; Staveley-Smith, Lister; Tian, Wen Wu; Umana, Grazia; Wagg, Jeff; Bourke, Tyler L; AASKA14

2015-01-01

In 2014 it was 10 years since the publication of the comprehensive ‘Science with the Square Kilometre Array’ book and 15 years since the first such volume appeared in 1999. In that time numerous and unexpected advances have been made in the fields of astronomy and physics relevant to the capabilities of the Square Kilometre Array (SKA). The SKA itself progressed from an idea to a developing reality with a baselined Phase 1 design (SKA1) and construction planned from 2017. To facilitate the publication of a new, updated science book, which will be relevant to the current astrophysical context, the meeting "Advancing Astrophysics with the Square Kilometre Array" was held in Giardina Naxos, Sicily. Articles were solicited from the community for that meeting to document the scientific advances enabled by the first phase of the SKA and those pertaining to future SKA deployments, with expected gains of 5 times the Phase 1 sensitivity below 350 MHz, about 10 times the Phase 1 sensitivity above 350 MHz and with f...

An oceanographic model for the dispersion of wastes disposed of in the deep sea

International Nuclear Information System (INIS)

1986-01-01

This report reviews the present knowledge of oceanic processes by which substances might be transferred from a deep-sea dump site back to man or his food chain and recommends pragmatic ways to calculate such transfers in order that deep-sea dumping of contaminants may be regulated effectively. The recommendations as to the currently most appropriate models are given

Bacterial community diversity of the deep-sea octocoral Paramuricea placomus

Directory of Open Access Journals (Sweden)

Christina A. Kellogg

2016-09-01

Full Text Available Compared to tropical corals, much less is known about deep-sea coral biology and ecology. Although the microbial communities of some deep-sea corals have been described, this is the first study to characterize the bacterial community associated with the deep-sea octocoral, Paramuricea placomus. Samples from five colonies of P. placomus were collected from Baltimore Canyon (379–382 m depth in the Atlantic Ocean off the east coast of the United States of America. DNA was extracted from the coral samples and 16S rRNA gene amplicons were pyrosequenced using V4-V5 primers. Three samples sequenced deeply (>4,000 sequences each and were further analyzed. The dominant microbial phylum was Proteobacteria, but other major phyla included Firmicutes and Planctomycetes. A conserved community of bacterial taxa held in common across the three P. placomus colonies was identified, comprising 68–90% of the total bacterial community depending on the coral individual. The bacterial community of P. placomus does not appear to include the genus Endozoicomonas, which has been found previously to be the dominant bacterial associate in several temperate and tropical gorgonians. Inferred functionality suggests the possibility of nitrogen cycling by the core bacterial community.

Age, growth rates, and paleoclimate studies of deep sea corals

Science.gov (United States)

Prouty, Nancy G; Roark, E. Brendan; Andrews, Allen; Robinson, Laura; Hill, Tessa; Sherwood, Owen; Williams, Branwen; Guilderson, Thomas P.; Fallon, Stewart

2015-01-01

Deep-water corals are some of the slowest growing, longest-lived skeletal accreting marine organisms. These habitat-forming species support diverse faunal assemblages that include commercially and ecologically important organisms. Therefore, effective management and conservation strategies for deep-sea corals can be informed by precise and accurate age, growth rate, and lifespan characteristics for proper assessment of vulnerability and recovery from perturbations. This is especially true for the small number of commercially valuable, and potentially endangered, species that are part of the black and precious coral fisheries (Tsounis et al. 2010). In addition to evaluating time scales of recovery from disturbance or exploitation, accurate age and growth estimates are essential for understanding the life history and ecology of these habitat-forming corals. Given that longevity is a key factor for population maintenance and fishery sustainability, partly due to limited and complex genetic flow among coral populations separated by great distances, accurate age structure for these deep-sea coral communities is essential for proper, long-term resource management.

The MEUST deep sea infrastructure in the Toulon site

Directory of Open Access Journals (Sweden)

Lamare Patrick

2016-01-01

Full Text Available The MEUST infrastructure (Mediterranean Eurocentre for Underwater Sciences and Technologies is a permanent deep sea cabled infrastructure currently being deployed off shore of Toulon, France. The design and the status of the infrastructure are presented.

Trace elements and stable isotope ratios (δ13C and δ15N) in fish from deep-waters of the Sulu Sea and the Celebes Sea

International Nuclear Information System (INIS)

Asante, Kwadwo Ansong; Agusa, Tetsuro; Kubota, Reiji; Mochizuki, Hiroko; Ramu, Karri; Nishida, Shuhei; Ohta, Suguru; Yeh, Hsin-ming; Subramanian, Annamalai; Tanabe, Shinsuke

2010-01-01

Trace elements (TEs) and stable isotope ratios (δ 15 N and δ 13 C) were analyzed in fish from deep-water of the Sulu Sea, the Celebes Sea and the Philippine Sea. Concentrations of V and Pb in pelagic fish from the Sulu Sea were higher than those from the Celebes Sea, whereas the opposite trend was observed for δ 13 C. High concentrations of Zn, Cu and Ag were found in non-migrant fish in deep-water, while Rb level was high in fish which migrate up to the epipelagic zone, probably resulting from differences in background levels of these TEs in each water environment or function of adaptation to deep-water by migrant and non-migrant species. Arsenic level in the Sulu Sea fish was positively correlated with δ 15 N, indicating biomagnification of arsenic. To our knowledge, this is the first study on relationship between diel vertical migration and TE accumulation in deep-water fish.

Species diversity variations in Neogene deep-sea benthic

Indian Academy of Sciences (India)

Some species of benthic foraminifera are sensitive to changes in water mass properties whereas others are sensitive to organic fluxes and deep-sea oxygenation. Benthic faunal diversity has been found closely linked to food web, bottom water oxygen levels, and substrate and water mass stability. The present study is ...

Feeding in deep-sea demosponges: Influence of abiotic and biotic factors

Science.gov (United States)

Robertson, Leah M.; Hamel, Jean-François; Mercier, Annie

2017-09-01

In shallow benthic communities, sponges are widely recognized for their ability to contribute to food webs by cycling nutrients and mediating carbon fluxes through filter feeding. In comparison, little is known about filter feeding in deep-sea species and how it may be modulated by environmental conditions. Here, a rare opportunity to maintain live healthy deep-sea sponges for an extended period led to a preliminary experimental study of their feeding metrics. This work focused on demosponges collected from the continental slope of eastern Canada at 1000 m depth. Filtration rates (as clearance of phytoplankton cells) at holding temperature (6 °C) were positively correlated with food particle concentration, ranging on average from 18.8 to 160.6 cells ml-1 h-1 at nominal concentrations of 10,000-40,000 cells ml-1. Cell clearance was not significantly affected by decreasing seawater temperature, from 6 °C to 3 °C or 0 °C, although two of the sponges showed decreased filtration rates. Low pH ( 7.5) and the presence of a predatory sea star markedly depressed or inhibited feeding activity in all sponges tested. While performed under laboratory conditions on a limited number of specimens, this work highlights the possible sensitivity of deep-sea demosponges to various types and levels of biotic and abiotic factors, inferring a consequent vulnerability to natural and anthropogenic disturbances.

Possibility of observing high energy neutrinos from gamma bursts, with the Antanares telescope, feasibility study; Possibilite d'observation, par le telescope antares, de neutrinos de haute energie associes aux sursauts gamma et validation des techniques de detection a l'aide d'un prototype

Energy Technology Data Exchange (ETDEWEB)

Kouchner, A

2001-04-01

The European Antares collaboration intends to build a deep-sea neutrino telescope with a detection surface of about 1/10 km{sup 2} in the Mediterranean sea. The universe is transparent to neutrinos, so their study provides a unique means of improving our knowledge of the nature and origin of cosmic rays and their emission from the most powerful astrophysical sources in the cosmos. Neutrinos also offer the possibility of opening a new energy window (E>TeV) for observation of the universe. The first part of the thesis is dedicated to a study of the possibility of using the future telescope to look for correlations between gamma-ray bursts and high-energy neutrinos. It is based, on one hand, on the predictions of neutrino fluxes from gamma-ray bursts in the framework of the theoretical model of 'fireballs', and, on the other hand, on the temporal properties of the gamma-ray bursts in the 4. BATSE catalogue. The second part of the thesis presents the results obtained with a prototype detector line deployed, at the end of 1999, some forty km south-west off Marseilles. The objective was to operate a complete apparatus, similar to the future detector lines, from the shore, and under realistic conditions. Data from 7 photomultiplier tubes disposed along the detector line were transmitted through 37 km of optical fiber to the shore, where they were used to reconstruct tracks due to atmospheric muons, thus validating the detection principles and methods. (author)

Fossil manganese nodules from Timor: geochemical and radiochemical evidence for deep-sea origin

International Nuclear Information System (INIS)

Margolis, S.V.; Fein, C.D.; Glasby, G.P.; Audley-Charles, M.G.

1978-01-01

Fossil Mn nodules of Cretaceous age from western Timor exhibit chemical, structural and radioisotope compositions consistent with their being of deep-sea origin. These nodules show characteristics similar to nodules now found at depths of 3,500-5,000 m in the Pacific and Indian Oceans. Slight differences in the fine structure and chemistry of these nodules and modern deep-sea nodules are attributed to diagenetic alteration after uplift of enclosing sediments

Determination of the atmospheric muon flux with the neutrino telescope ANTARES

International Nuclear Information System (INIS)

Picq, C.

2009-06-01

The neutrino telescope ANTARES is a deep-sea detector located in the Mediterranean Sea. The universe is transparent to neutrinos, so their study provides a unique means of improving our knowledge of the nature of cosmic rays, their origins and their emission from the most powerful astrophysical sources in the cosmos. Neutrinos also offer the possibility of opening a new energy window (>TeV) for observation of the universe. This thesis is dedicated to the study of the main background noise of the detector, due to the passage of atmospheric muons produced by high energy cosmic rays interacting with atmospheric nuclei. The first part of this thesis focuses on the study of the detector. The different characteristics and the calibration of the detector as well as the techniques of monitoring the electronic are described. The second part of this thesis reports the various results obtained on the atmospheric muons with the five line detector. A detailed presentation of the simulations used is presented. The first difficulty of detecting atmospheric muons is due to the geometry of the detector. The second is due to the fact that the atmospheric muons often arrive in bundles and that the number of muons in these bundles is unknown at a depth of 2500 m. A first study based on simulations makes it possible to discriminate between the muons alone and the bundles of muons. A second study is dedicated to the measurement of the muon flux depending on the slant depth. The measurement is compatible with the results of other instruments when the systematic uncertainties are taken into account. (author)

Evidence for infragravity wave-tide resonance in deep oceans.

Science.gov (United States)

Sugioka, Hiroko; Fukao, Yoshio; Kanazawa, Toshihiko

2010-10-05

Ocean tides are the oscillatory motions of seawater forced by the gravitational attraction of the Moon and Sun with periods of a half to a day and wavelengths of the semi-Pacific to Pacific scale. Ocean infragravity (IG) waves are sea-surface gravity waves with periods of several minutes and wavelengths of several dozen kilometres. Here we report the first evidence of the resonance between these two ubiquitous phenomena, mutually very different in period and wavelength, in deep oceans. The evidence comes from long-term, large-scale observations with arrays of broadband ocean-bottom seismometers located at depths of more than 4,000 m in the Pacific Ocean. This observational evidence is substantiated by a theoretical argument that IG waves and the tide can resonantly couple and that such coupling occurs over unexpectedly wide areas of the Pacific Ocean. Through this resonant coupling, some of ocean tidal energy is transferred in deep oceans to IG wave energy.

Contrasting trends in North Atlantic deep-water formation in the Labrador Sea and Nordic Seas during the Holocene

NARCIS (Netherlands)

Renssen, H.; Goosse, H.; Fichefet, T.

2005-01-01

The Holocene North Atlantic deep-water formation is studied in a 9,000-year long simulation with a coupled climate model of intermediate complexity, forced by changes in orbital forcing and atmospheric trace gas concentrations. During the experiment, deep-water formation in the Nordic Seas is

Food web structure and vulnerability of a deep-sea ecosystem in the NW Mediterranean Sea

OpenAIRE

Tecchio, Samuele; Coll, Marta; Christensen, Villy; Company, Joan B.; Ramirez-Llodra, Eva; Sarda, Francisco

2013-01-01

There is increasing fishing pressure on the continental margins of the oceans, and this raises concerns about the vulnerability of the ecosystems thriving there. The current knowledge of the biology of deep-water fish species identifies potential reduced resilience to anthropogenic disturbance. However, there are extreme difficulties in sampling the deep sea, resulting in poorly resolved and indirectly obtained food-web relationships. Here, we modelled the flows and biomasses of a Mediterrane...

Adaptation and evolution of deep-sea scale worms (Annelida: Polynoidae): insights from transcriptome comparison with a shallow-water species

Science.gov (United States)

Zhang, Yanjie; Sun, Jin; Chen, Chong; Watanabe, Hiromi K.; Feng, Dong; Zhang, Yu; Chiu, Jill M.Y.; Qian, Pei-Yuan; Qiu, Jian-Wen

2017-01-01

Polynoid scale worms (Polynoidae, Annelida) invaded deep-sea chemosynthesis-based ecosystems approximately 60 million years ago, but little is known about their genetic adaptation to the extreme deep-sea environment. In this study, we reported the first two transcriptomes of deep-sea polynoids (Branchipolynoe pettiboneae, Lepidonotopodium sp.) and compared them with the transcriptome of a shallow-water polynoid (Harmothoe imbricata). We determined codon and amino acid usage, positive selected genes, highly expressed genes and putative duplicated genes. Transcriptome assembly produced 98,806 to 225,709 contigs in the three species. There were more positively charged amino acids (i.e., histidine and arginine) and less negatively charged amino acids (i.e., aspartic acid and glutamic acid) in the deep-sea species. There were 120 genes showing clear evidence of positive selection. Among the 10% most highly expressed genes, there were more hemoglobin genes with high expression levels in both deep-sea species. The duplicated genes related to DNA recombination and metabolism, and gene expression were only enriched in deep-sea species. Deep-sea scale worms adopted two strategies of adaptation to hypoxia in the chemosynthesis-based habitats (i.e., rapid evolution of tetra-domain hemoglobin in Branchipolynoe or high expression of single-domain hemoglobin in Lepidonotopodium sp.). PMID:28397791

Recent developments in the thermophilic microbiology of deep-sea hydrothermal vents.

Science.gov (United States)

Miroshnichenko, Margarita L; Bonch-Osmolovskaya, Elizaveta A

2006-04-01

The diversity of thermophilic prokaryotes inhabiting deep-sea hot vents was actively studied over the last two decades. The ever growing interest is reflected in the exponentially increasing number of novel thermophilic genera described. The goal of this paper is to survey the progress in this field made in the years 2000-2005. In this period, representatives of several new taxa of hyperthermophilic archaea were obtained from deep-sea environments. Two of these isolates had phenotypic features new for this group of organisms: the presence of an outer cell membrane (the genus Ignicoccus) and the ability to grow anaerobically with acetate and ferric iron (the genus Geoglobus). Also, our knowledge on the diversity of thermophilic bacteria from deep-sea thermal environments extended significantly. The new bacterial isolates represented diverse bacterial divisions: the phylum Aquificae, the subclass Epsilonproteobacteria, the order Thermotogales, the families Thermodesulfobacteriaceae, Deferribacteraceae, and Thermaceae, and a novel bacterial phylum represented by the genus Caldithrix. Most of these isolates are obligate or facultative lithotrophs, oxidizing molecular hydrogen in the course of different types of anaerobic respiration or microaerobic growth. The existence and significant ecological role of some of new bacterial thermophilic isolates was initially established by molecular methods.

Sources of the deep water masses in the northern Red Sea

OpenAIRE

Said, M.A.

1998-01-01

The hydrographic structure of the northern Red Sea indicated that, the surface waters of temperature around 22°C, salinity of 40.1OO%o and dt = 28.1 might sink to depths between 400-500 m by convective overturn, contributing to the formation of the mid-deep Red Sea waters. Below the 500 db depth down to the bottom the water column is stable. The geostrophic circulation clearly indicated an inflow of water from the Red Sea towards NNW, along the main axis of the sea. Arriving at the nort...

Microbial community composition of deep-sea corals from the Red Sea provides insight into functional adaption to a unique environment.

Science.gov (United States)

Röthig, Till; Yum, Lauren K; Kremb, Stephan G; Roik, Anna; Voolstra, Christian R

2017-03-17

Microbes associated with deep-sea corals remain poorly studied. The lack of symbiotic algae suggests that associated microbes may play a fundamental role in maintaining a viable coral host via acquisition and recycling of nutrients. Here we employed 16 S rRNA gene sequencing to study bacterial communities of three deep-sea scleractinian corals from the Red Sea, Dendrophyllia sp., Eguchipsammia fistula, and Rhizotrochus typus. We found diverse, species-specific microbiomes, distinct from the surrounding seawater. Microbiomes were comprised of few abundant bacteria, which constituted the majority of sequences (up to 58% depending on the coral species). In addition, we found a high diversity of rare bacteria (taxa at 90% of all bacteria). Interestingly, we identified anaerobic bacteria, potentially providing metabolic functions at low oxygen conditions, as well as bacteria harboring the potential to degrade crude oil components. Considering the presence of oil and gas fields in the Red Sea, these bacteria may unlock this carbon source for the coral host. In conclusion, the prevailing environmental conditions of the deep Red Sea (>20 °C, <2 mg oxygen L -1 ) may require distinct functional adaptations, and our data suggest that bacterial communities may contribute to coral functioning in this challenging environment.

Microbial community composition of deep-sea corals from the Red Sea provides insight into functional adaption to a unique environment

KAUST Repository

Röthig, Till

2017-03-17

Microbes associated with deep-sea corals remain poorly studied. The lack of symbiotic algae suggests that associated microbes may play a fundamental role in maintaining a viable coral host via acquisition and recycling of nutrients. Here we employed 16 S rRNA gene sequencing to study bacterial communities of three deep-sea scleractinian corals from the Red Sea, Dendrophyllia sp., Eguchipsammia fistula, and Rhizotrochus typus. We found diverse, species-specific microbiomes, distinct from the surrounding seawater. Microbiomes were comprised of few abundant bacteria, which constituted the majority of sequences (up to 58% depending on the coral species). In addition, we found a high diversity of rare bacteria (taxa at <1% abundance comprised >90% of all bacteria). Interestingly, we identified anaerobic bacteria, potentially providing metabolic functions at low oxygen conditions, as well as bacteria harboring the potential to degrade crude oil components. Considering the presence of oil and gas fields in the Red Sea, these bacteria may unlock this carbon source for the coral host. In conclusion, the prevailing environmental conditions of the deep Red Sea (>20 °C, <2 mg oxygen L−1) may require distinct functional adaptations, and our data suggest that bacterial communities may contribute to coral functioning in this challenging environment.

The Effects of Temperature and Hydrostatic Pressure on Metal Toxicity: Insights into Toxicity in the Deep Sea.

Science.gov (United States)

Brown, Alastair; Thatje, Sven; Hauton, Chris

2017-09-05

Mineral prospecting in the deep sea is increasing, promoting concern regarding potential ecotoxicological impacts on deep-sea fauna. Technological difficulties in assessing toxicity in deep-sea species has promoted interest in developing shallow-water ecotoxicological proxy species. However, it is unclear how the low temperature and high hydrostatic pressure prevalent in the deep sea affect toxicity, and whether adaptation to deep-sea environmental conditions moderates any effects of these factors. To address these uncertainties we assessed the effects of temperature and hydrostatic pressure on lethal and sublethal (respiration rate, antioxidant enzyme activity) toxicity in acute (96 h) copper and cadmium exposures, using the shallow-water ecophysiological model organism Palaemon varians. Low temperature reduced toxicity in both metals, but reduced cadmium toxicity significantly more. In contrast, elevated hydrostatic pressure increased copper toxicity, but did not affect cadmium toxicity. The synergistic interaction between copper and cadmium was not affected by low temperature, but high hydrostatic pressure significantly enhanced the synergism. Differential environmental effects on toxicity suggest different mechanisms of action for copper and cadmium, and highlight that mechanistic understanding of toxicity is fundamental to predicting environmental effects on toxicity. Although results infer that sensitivity to toxicants differs across biogeographic ranges, shallow-water species may be suitable ecotoxicological proxies for deep-sea species, dependent on adaptation to habitats with similar environmental variability.

Borders of life: lessons from Microbiology of deep-sea hydrothermal vents

Science.gov (United States)

Prieur, D.

Thirty years ago, the deep-sea was known as a low density biotope due to coldness, darkness and famine-like conditions. The discovery of deep-sea hydrothermal vents in the Eastern Pacific in 1977 and the associated black smokers in 1979 considerably changed our views about life on Earth. For the first time, an ecosystem almost independent (at least for tens of years) of solar nergy was discovered. Besides the spectacular and unexpected communities of invertebrates based on symbiotic associations with chemo-litho-autotrophic bacteria, prokaryotic communities associated with high temperature black smokers fascinated microbiologists of extreme environments. Within mineral structures where temperature gradients may fluctuate from ambient seawater temperatures (2°C) up to 350°C, thermophilic (optimal growth above 60°C) and hyperthermophilic (optimal growth above 80°C) microorganisms thrived under very severe conditions due to elevated hydrostatic pressure, toxic compounds or strong ionizing radiations. These organisms belong to both domains of Bacteria and Archaea and live aerobically but mostly anaerobically, using a variety of inorganic and organic carbon sources, and a variety of electron donnors and acceptors as well. The most thermophilic organism known on Earth was isolated from a mid-Atlantic-Ridge hydrotermal vent: Pyrolobus fumarii grows optimally at 110°c and its upper temperature limit for life is 113°C. Such an organism survived to autoclaving conditions currently used for sterilization procedures. Many other hyperthermophilic organisms were isolated and described, including fermenters, sulphate and sulphur reducers, hydrogen oxidizers, nitrate reducers, methanogens, etc. Although most of anaerobes are killed when exposed to oxygen, several deep-sea hyperthermophiles appeared to survive to both oxygen and starvation exposures, indicating that they probably can colonize rather distant environments Because of elevated hydrostatic pressure that exists at

Global diversity and biogeography of deep-sea pelagic prokaryotes

KAUST Repository

Salazar, Guillem

2015-08-07

The deep-sea is the largest biome of the biosphere, and contains more than half of the whole ocean\\'s microbes. Uncovering their general patterns of diversity and community structure at a global scale remains a great challenge, as only fragmentary information of deep-sea microbial diversity exists based on regional-scale studies. Here we report the first globally comprehensive survey of the prokaryotic communities inhabiting the bathypelagic ocean using high-throughput sequencing of the 16S rRNA gene. This work identifies the dominant prokaryotes in the pelagic deep ocean and reveals that 50% of the operational taxonomic units (OTUs) belong to previously unknown prokaryotic taxa, most of which are rare and appear in just a few samples. We show that whereas the local richness of communities is comparable to that observed in previous regional studies, the global pool of prokaryotic taxa detected is modest (∼3600 OTUs), as a high proportion of OTUs are shared among samples. The water masses appear to act as clear drivers of the geographical distribution of both particle-attached and free-living prokaryotes. In addition, we show that the deep-oceanic basins in which the bathypelagic realm is divided contain different particle-attached (but not free-living) microbial communities. The combination of the aging of the water masses and a lack of complete dispersal are identified as the main drivers for this biogeographical pattern. All together, we identify the potential of the deep ocean as a reservoir of still unknown biological diversity with a higher degree of spatial complexity than hitherto considered.

Global diversity and biogeography of deep-sea pelagic prokaryotes

KAUST Repository

Salazar, Guillem; Cornejo-Castillo, Francisco M.; Bení tez-Barrios, Veró nica; Fraile-Nuez, Eugenio; Á lvarez-Salgado, X. Antó n; Duarte, Carlos M.; Gasol, Josep M.; Acinas, Silvia G.

2015-01-01

The deep-sea is the largest biome of the biosphere, and contains more than half of the whole ocean's microbes. Uncovering their general patterns of diversity and community structure at a global scale remains a great challenge, as only fragmentary information of deep-sea microbial diversity exists based on regional-scale studies. Here we report the first globally comprehensive survey of the prokaryotic communities inhabiting the bathypelagic ocean using high-throughput sequencing of the 16S rRNA gene. This work identifies the dominant prokaryotes in the pelagic deep ocean and reveals that 50% of the operational taxonomic units (OTUs) belong to previously unknown prokaryotic taxa, most of which are rare and appear in just a few samples. We show that whereas the local richness of communities is comparable to that observed in previous regional studies, the global pool of prokaryotic taxa detected is modest (∼3600 OTUs), as a high proportion of OTUs are shared among samples. The water masses appear to act as clear drivers of the geographical distribution of both particle-attached and free-living prokaryotes. In addition, we show that the deep-oceanic basins in which the bathypelagic realm is divided contain different particle-attached (but not free-living) microbial communities. The combination of the aging of the water masses and a lack of complete dispersal are identified as the main drivers for this biogeographical pattern. All together, we identify the potential of the deep ocean as a reservoir of still unknown biological diversity with a higher degree of spatial complexity than hitherto considered.

Search for tau-neutrino induced cascades in the IceCube detector

Energy Technology Data Exchange (ETDEWEB)

Usner, Marcel; Kowalski, Marek [DESY, Zeuthen (Germany); Collaboration: IceCube-Collaboration

2016-07-01

The IceCube Neutrino Observatory at the South Pole is a Cherenkov detector built to measure high-energy neutrinos from cosmic sources. A total volume of about one cubic kilometer of the Antarctic ice is instrumented with 5160 optical modules. A tau lepton is created in the charged current interaction of a tau neutrino with an ice nucleus. The Double Bang signature links two subsequent cascades from the hadronic interaction and the tau decay within the detection volume. It can only be resolved at the highest energies around 1 PeV where the decay length of the tau is about 50 m. The work is focused on optimizing reconstruction methods of Double Bang events incorporating the latest ice model. The goal is to measure a flavor ratio that, for the first time, is sensitive to tau neutrinos.

Environmental studies for mining of deep-sea polymetallic nodules - Accomplishments and future plans

Digital Repository Service at National Institute of Oceanography (India)

Sharma, R.

on marine ecosystem, the project on ‘EIA studies for nodule mining in CIB’ was initiated in 1996, under the national programme on polymetallic nodules funded by the Dept. of Ocean Development. Mining of the deep-sea minerals [1] is expected to alter... for the future • Development of predictive ecosystem models • Creation of environmental database • Evaluating the biogeochemical coupling of biota with deep-sea ecosystem • Development of environment management plan for nodule mining References...

Microbiology of the Red Sea (and other) deep-sea anoxic brine lakes

KAUST Repository

Antunes, Andre

2011-05-30

Summary: The Red Sea harbours approximately 25 deep-sea anoxic brine pools. They constitute extremely unique and complex habitats with the conjugation of several extreme physicochemical parameters rendering them some of the most inhospitable environments on Earth. After 50 years of research mostly driven by chemists, geophysicists and geologists, the microbiology of the brines has been receiving increased interest in the last decade. Recent molecular and cultivation-based studies have provided us with a first glimpse on the enormous biodiversity of the local microbial communities, the identification of several new taxonomic groups, and the isolation of novel extremophiles that thrive in these environments. This review presents a general overview of these unusual biotopes and compares them with other similar environments in the Mediterranean Sea and the Gulf of Mexico, with a focus on their microbial ecology. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

Deep-sea Lebensspuren of the Australian continental margins

Science.gov (United States)

Przeslawski, Rachel; Dundas, Kate; Radke, Lynda; Anderson, Tara J.

Much of the deep sea comprises soft-sediment habitats dominated by comparatively low abundances of species-rich macrofauna and meiofauna. Although often not observed, these animals bioturbate the sediment during feeding and burrowing, leaving signs of their activities called Lebensspuren ('life traces'). In this study, we use still images to quantify Lebensspuren from the eastern (1921 images, 13 stations, 1300-2200 m depth) and western (1008 images, 11 stations, 1500-4400 m depth) Australian margins using a univariate measure of trace richness and a multivariate measure of Lebensspuren assemblages. A total of 46 Lebensspuren types were identified, including those matching named trace fossils and modern Lebensspuren found elsewhere in the world. Most traces could be associated with waste, crawling, dwellings, organism tests, feeding, or resting, but the origin of 15% of trace types remains unknown. Assemblages were significantly different between the two regions and depth profiles, with five Lebensspuren types accounting for over 95% of the differentiation (ovoid pinnate trace, crater row, spider trace, matchstick trace, mesh trace). Lebensspuren richness showed no strong relationships with depth, total organic carbon, or mud, although there was a positive correlation to chlorin index (i.e., organic freshness) in the eastern margin, with richness increasing with organic freshness. Lebensspuren richness was not related to epifauna either, indicating that epifauna may not be the primary source of Lebensspuren. Despite the abundance and distinctiveness of several traces both in the current and previous studies (e.g., ovoid pinnate, mesh, spider), their origin and distribution remains a mystery. We discuss this and several other considerations in the identification and quantification of Lebensspuren. This study represents the first comprehensive catalogue of deep-sea Lebensspuren in Australian waters and highlights the potential of Lebensspuren as valuable and often

Harpacticoid copepod diversity at two physically reworked sites in the deep sea

Science.gov (United States)

Thistle, David

1998-01-01

Grassle's and Jumars' theories of diversity maintenance in the quiescent deep sea view millimeter-to-meter-scale patchiness (mostly of biological origin) as crucial. In other deep-sea regions, episodes of strong near-bottom flow put the surficial sediment layers into motion, obliterating the biologically produced, millimeter-to-meter-scale patchiness. Under these theories, sites eroded so frequently that such patchiness is eliminated almost as soon as it is created should have lower diversities than sites where the time between erosive events is sufficient for this type of patchiness to be produced and exploited. I tested this prediction by comparing the diversities of harpacticoid copepods at two sites on Fieberling Guyot to determine whether Grassle's and Jumars' theories can be extended to the portion of the deep sea that experiences episodic erosive flows. At White Sand Swale (=WSS) (32°27.581'N, 127°47.839'W), strong near-bottom flows erode the surficial sediment daily. At Sea Pen Rim (=SPR) (32°27.631'N, 127°49.489'W), strong near-bottom flows erode the surficial sediment a few times annually. Contrary to expectation, the diversity of harpacticoid copepods was significantly greater at WSS than at SPR. However, the erosion regime at WSS may create small-scale patchiness that promotes harpacticoid diversity.

Atmospheric neutrino oscillations for earth tomography

International Nuclear Information System (INIS)

Winter, Walter

2016-01-01

Modern proposed atmospheric neutrino oscillation experiments, such as PINGU in the Antarctic ice or ORCA in Mediterranean sea water, aim for precision measurements of the oscillation parameters including the ordering of the neutrino masses. They can, however, go far beyond that: Since neutrino oscillations are affected by the coherent forward scattering with matter, neutrinos can provide a new view on the interior of the earth. We show that the proposed atmospheric oscillation experiments can measure the lower mantle density of the earth with a precision at the level of a few percent, including the uncertainties of the oscillation parameters and correlations among different density layers. While the earth's core is, in principle, accessible by the angular resolution, new technology would be required to extract degeneracy-free information.

A Moessbauer study of deep sea sediments

International Nuclear Information System (INIS)

Minai, Y.; Tominaga, T.; Furuta, T.; Kobayashi, K.

1981-01-01

In order to determine the chemical states of iron in deep sea sediments, Moessbauer spectra of the sediments collected from various areas of the Pacific have been measured. The Moessbauer spectra were composed of paramagnetic ferric, high-spin ferrous, and magnetic components. The correlation of their relative abundance to the sampling location and the kind of sediments may afford clues to infer the origin of each iron-bearing phase. (author)

Earth Effects and Mass Hierarchy with Supernova Neutrinos

International Nuclear Information System (INIS)

Dasgupta, Basudeb

2009-01-01

Collective neutrino flavor transformations take place deep inside a supernova if the neutrino mass hierarchy is inverted, even for extremely small values of θ 13 . We show that the presence (or absence) of Earth matter effects in antineutrino signal is directly related to the absence (or presence) of these collective effects, when the mixing angle θ 13 is small. Thus a neutrino signal from a galactic supernova may enable us to distinguish between the hierarchies even for small values of θ 13 .

An oceanographic model for the dispersion of wastes disposed of in the deep sea

International Nuclear Information System (INIS)

1983-06-01

The report presents results of IMO/FAO/UNESCO/WMO/WHO/IAEA/UN/UNEP joint group of experts on the scientific aspects of marine pollution (GESAMP) to provide advice on the most suitable oceanographic modelling techniques to be applied to the deep-sea dumping of both radioactive and non-radioactive substances. There are four main parts of the work: the present knowledge of oceanic processes that may transfer substances from a deep-sea dump site back to man or his food chain, methods and models presently available for estimating or calculating concentration distributions of contaminants arising from releases from deep-sea dump sites and recommendations as to the presently most appropriate models, the reliability of the concentration distributions obtained using these models and recommended areas for further improvements including research needs

The Deep-Sea Microbial Community from the Amazonian Basin Associated with Oil Degradation.

Science.gov (United States)

Campeão, Mariana E; Reis, Luciana; Leomil, Luciana; de Oliveira, Louisi; Otsuki, Koko; Gardinali, Piero; Pelz, Oliver; Valle, Rogerio; Thompson, Fabiano L; Thompson, Cristiane C

2017-01-01

One consequence of oil production is the possibility of unplanned accidental oil spills; therefore, it is important to evaluate the potential of indigenous microorganisms (both prokaryotes and eukaryotes) from different oceanic basins to degrade oil. The aim of this study was to characterize the microbial response during the biodegradation process of Brazilian crude oil, both with and without the addition of the dispersant Corexit 9500, using deep-sea water samples from the Amazon equatorial margin basins, Foz do Amazonas and Barreirinhas, in the dark and at low temperatures (4°C). We collected deep-sea samples in the field (about 2570 m below the sea surface), transported the samples back to the laboratory under controlled environmental conditions (5°C in the dark) and subsequently performed two laboratory biodegradation experiments that used metagenomics supported by classical microbiological methods and chemical analysis to elucidate both taxonomic and functional microbial diversity. We also analyzed several physical-chemical and biological parameters related to oil biodegradation. The concomitant depletion of dissolved oxygen levels, oil droplet density characteristic to oil biodegradation, and BTEX concentration with an increase in microbial counts revealed that oil can be degraded by the autochthonous deep-sea microbial communities. Indigenous bacteria (e.g., Alteromonadaceae, Colwelliaceae , and Alcanivoracaceae ), archaea (e.g., Halobacteriaceae, Desulfurococcaceae , and Methanobacteriaceae ), and eukaryotic microbes (e.g., Microsporidia, Ascomycota, and Basidiomycota) from the Amazonian margin deep-sea water were involved in biodegradation of Brazilian crude oil within less than 48-days in both treatments, with and without dispersant, possibly transforming oil into microbial biomass that may fuel the marine food web.

From Exploration to Exploitation? Opportunities and Imperatives in the Deep Sea

KAUST Repository

Van Dover, Cindy Lee

2017-01-16

We may think of the depths of the ocean as unseen, unfathomable, but there have been breakthroughs in technology that allow scientists access to the deep sea and that bring the deep sea directly to the public through live video feeds and data links. We can now map the seafloor to resolve features the size of a football and smaller using sound waves, while at the same time, sensors report to us the chemical nature of the surrounding environment. We will look at examples of robots and other assets that we use to explore the seafloor and at some of the discoveries that arise from our expanding capabilities. We will look at some of the blank places on the map and wonder what might be located there. And finally, we will explore the growing interest in mining the seabed and the potential for a Blue Economy in the deep ocean.

NEMO-SMO acoustic array: A deep-sea test of a novel acoustic positioning system for a km3-scale underwater neutrino telescope

Science.gov (United States)

Viola, S.; Ardid, M.; Bertin, V.; Enzenhöfer, A.; Keller, P.; Lahmann, R.; Larosa, G.; Llorens, C. D.; NEMO Collaboration; SMO Collaboration

2013-10-01

Within the activities of the NEMO project, the installation of a 8-floors tower (NEMO-Phase II) at a depth of 3500 m is foreseen in 2012. The tower will be installed about 80 km off-shore Capo Passero, in Sicily. On board the NEMO tower, an array of 18 acoustic sensors will be installed, permitting acoustic detection of biological sources, studies for acoustic neutrino detection and primarily acoustic positioning of the underwater structures. For the latter purpose, the sensors register acoustic signals emitted by five acoustic beacons anchored on the sea-floor. The data acquisition system of the acoustic sensors is fully integrated with the detector data transport system and is based on an “all data to shore” philosophy. Signals coming from hydrophones are continuously sampled underwater at 192 kHz/24 bit and transmitted to shore through an electro-optical cable for real-time analysis. A novel technology for underwater GPS time-stamping of data has been implemented and tested. The operation of the acoustic array will permit long-term test of sensors and electronics technologies that are proposed for the acoustic positioning system of KM3NeT.

Ecosystem Services: a Framework for Environmental Management of the Deep Sea

Science.gov (United States)

Le, J. T.; Levin, L. A.; Carson, R. T.

2016-02-01

As demand for deep-sea resources rapidly expands in the food, energy, mineral, and pharmaceutical sectors, it has become increasingly clear that a regulatory structure for extracting these resources is not yet in place. There are jurisdictional gaps and a lack of regulatory consistency regarding what aspects of the deep sea need protection and what requirements might help guarantee that protection. Given the mining sector's intent to exploit seafloor massive sulphides, Mn nodules, cobalt crusts, and phosphorites in the coming years, there is an urgent need for deep-ocean environmental management. Here, we propose an ecosystem services-based framework to inform decisions and best practices regarding resource exploitation, and to guide baseline studies, preventative actions, monitoring, and remediation. With policy in early stages of development, an ecosystem services approach has the potential to serve as an overarching framework that takes protection of natural capital provided by the environment into account during the decision-making process. We show how an ecosystem services approach combined with economic tools, such as benefit transfer techniques, should help illuminate issues where there are direct conflicts among different industries, and between industry and conservation. We argue for baseline and monitoring measurements and metrics that inform about deep-sea ecosystem services that would be impaired by mining, and discuss ways to incorporate the value of those losses into decision making, mitigation measures, and ultimately product costs. This proposal is considered relative to current International Seabed Authority recommendations and contractor practices, and new actions are proposed. An ecosystem services-based understanding of how these systems work and their value to society can improve sustainability and stewardship of the deep ocean.

Metabolic profiles of prokaryotic and eukaryotic communities in deep-sea sponge Neamphius huxleyi indicated by metagenomics

Science.gov (United States)

Li, Zhi-Yong; Wang, Yue-Zhu; He, Li-Ming; Zheng, Hua-Jun

2014-01-01

The whole metabolism of a sponge holobiont and the respective contributions of prokaryotic and eukaryotic symbionts and their associations with the sponge host remain largely unclear. Meanwhile, compared with shallow water sponges, deep-sea sponges are rarely understood. Here we report the metagenomic exploration of deep-sea sponge Neamphius huxleyi at the whole community level. Metagenomic data showed phylogenetically diverse prokaryotes and eukaryotes in Neamphius huxleyi. MEGAN and gene enrichment analyses indicated different metabolic potentials of prokaryotic symbionts from eukaryotic symbionts, especially in nitrogen and carbon metabolisms, and their molecular interactions with the sponge host. These results supported the hypothesis that prokaryotic and eukaryotic symbionts have different ecological roles and relationships with sponge host. Moreover, vigorous denitrification, and CO2 fixation by chemoautotrophic prokaryotes were suggested for this deep-sea sponge. The study provided novel insights into the respective potentials of prokaryotic and eukaryotic symbionts and their associations with deep-sea sponge Neamphius huxleyi. PMID:24463735

Metabolic profiles of prokaryotic and eukaryotic communities in deep-sea sponge Lamellomorpha sp. indicated by metagenomics

Science.gov (United States)

Li, Zhi-Yong; Wang, Yue-Zhu; He, Li-Ming; Zheng, Hua-Jun

2014-01-01

The whole metabolism of a sponge holobiont and the respective contributions of prokaryotic and eukaryotic symbionts and their associations with the sponge host remain largely unclear. Meanwhile, compared with shallow water sponges, deep-sea sponges are rarely understood. Here we report the metagenomic exploration of deep-sea sponge Lamellomorpha sp. at the whole community level. Metagenomic data showed phylogenetically diverse prokaryotes and eukaryotes in Lamellomorpha sp.. MEGAN and gene enrichment analyses indicated different metabolic potentials of prokaryotic symbionts from eukaryotic symbionts, especially in nitrogen and carbon metabolisms, and their molecular interactions with the sponge host. These results supported the hypothesis that prokaryotic and eukaryotic symbionts have different ecological roles and relationships with sponge host. Moreover, vigorous denitrification, and CO2 fixation by chemoautotrophic prokaryotes were suggested for this deep-sea sponge. The study provided novel insights into the respective potentials of prokaryotic and eukaryotic symbionts and their associations with deep-sea sponge Lamellomorpha sp..

Experimental study of inclusive deep inelastic neutrino--proton scattering

International Nuclear Information System (INIS)

Berge, J.P.; Bogert, D.; DiBianca, F.A.; Cundy, D.C.; Dunaitsev, A.; Efremenko, V.; Ermolov, P.; Fowler, W.; Hanft, R.; Harigel, G.; Huson, F.R.; Kolganov, V.; Mukhin, A.; Nezrick, F.A.; Rjabov, Y.; Scott, W.G.; Smart, W.; Coffin, C.T.; Diamond, R.N.; French, H.; Louis, W.; Roe, B.P.; Seidl, A.A.; Velde, J.C.V.

1976-01-01

A neutrino--proton scattering experiment has been performed at Fermilab by using a wide-band horn-focused neutrino beam and the 15-ft bubble chamber filled with hydrogen. For the inclusive reaction ν/sub μ/ + p → μ - + hadrons, the mean value of Q 2 is found to increase linearly with energy, as is expected from Bjorken scaling, and a fit to the data gives 2 > = (0.18 +- 0.01) E. The distribution in the Bjorken scaling variable x shows evidence for deviations from predictions based on electron-scattering data and the quark-parton model

All-flavour search for neutrinos from dark matter annihilations in the Milky Way with IceCube/DeepCore

Energy Technology Data Exchange (ETDEWEB)

Aartsen, M.G.; Hill, G.C.; Robertson, S.; Wallace, A.; Whelan, B.J. [University of Adelaide, Department of Physics, Adelaide (Australia); Abraham, K.; Bernhard, A.; Coenders, S.; Holzapfel, K.; Huber, M.; Jurkovic, M.; Krings, K.; Resconi, E.; Turcati, A.; Veenkamp, J. [Technische Universitaet Muenchen, Physik-department, Garching (Germany); Ackermann, M.; Bernardini, E.; Blot, S.; Bretz, H.P.; Cruz Silva, A.H.; Franckowiak, A.; Gluesenkamp, T.; Gora, D.; Jacobi, E.; Karg, T.; Kintscher, T.; Kunwar, S.; Middell, E.; Mohrmann, L.; Nahnhauer, R.; Satalecka, K.; Schoenwald, A.; Spiering, C.; Stasik, A.; Stoessl, A.; Strotjohann, N.L.; Terliuk, A.; Usner, M.; Santen, J. van; Yanez, J.P. [DESY, Zeuthen (Germany); Adams, J. [University of Canterbury, Department of Physics and Astronomy, Private Bag 4800, Christchurch (New Zealand); Aguilar, J.A.; Ansseau, I.; Heereman, D.; Meagher, K.; Meures, T.; O' Murchadha, A.; Pinat, E.; Raab, C. [Universite Libre de Bruxelles, Science Faculty CP230, Brussels (Belgium); Ahlers, M.; Braun, J.; Chirkin, D.; Day, M.; Desiati, P.; Diaz-Velez, J.C.; Fahey, S.; Feintzeig, J.; Ghorbani, K.; Gladstone, L.; Griffith, Z.; Halzen, F.; Hanson, K.; Hoshina, K.; Jero, K.; Karle, A.; Kelley, J.L.; Kheirandish, A.; Krueger, C.; Mancina, S.; McNally, F.; Merino, G.; Sabbatini, L.; Tobin, M.N.; Tosi, D.; Vandenbroucke, J.; Van Rossem, M.; Wandkowsky, N.; Wendt, C.; Westerhoff, S.; Wille, L.; Xu, D.L. [University of Wisconsin, Department of Physics, Wisconsin IceCube Particle Astrophysics Center, Madison, WI (United States); Ahrens, M.; Bohm, C.; Dumm, J.P.; Finley, C.; Flis, S.; Hultqvist, K.; Walck, C.; Wolf, M.; Zoll, M. [Stockholm University, Department of Physics, Oskar Klein Centre, Stockholm (Sweden); Altmann, D.; Anton, G.; Katz, U.; Kittler, T.; Tselengidou, M. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Erlangen Centre for Astroparticle Physics, Erlangen (Germany); Andeen, K. [Marquette University, Department of Physics, Milwaukee, WI (United States); Anderson, T.; Arlen, T.C.; Dunkman, M.; Huang, F.; Keivani, A.; Lanfranchi, J.L.; Pankova, D.V.; Quinnan, M.; Tesic, G. [Pennsylvania State University, Department of Physics, University Park, PA (United States); Archinger, M.; Baum, V.; Boeser, S.; Del Pino Rosendo, E.; Di Lorenzo, V.; Eberhardt, B.; Ehrhardt, T.; Foesig, C.C.; Koepke, L.; Krueckl, G.; Sandroos, J.; Steuer, A.; Wiebe, K. [University of Mainz, Institute of Physics, Mainz (Germany); Arguelles, C.; Axani, S.; Collin, G.H.; Conrad, J.M.; Jones, B.J.P.; Moulai, M. [Massachusetts Institute of Technology, Department of Physics, Cambridge, MA (United States); Auffenberg, J.; Bissok, M.; Glagla, M.; Haack, C.; Hansmann, B.; Hansmann, T.; Kemp, J.; Konietz, R.; Leuermann, M.; Leuner, J.; Penek, Oe.; Raedel, L.; Reimann, R.; Rongen, M.; Schimp, M.; Schoenen, S.; Schumacher, L.; Stahlberg, M.; Vehring, M.; Wallraff, M.; Wickmann, S.; Wiebusch, C.H. [RWTH Aachen University, III. Physikalisches Institut, Aachen (Germany); Bai, X. [South Dakota School of Mines and Technology, Physics Department, Rapid City, SD (United States); Barwick, S.W.; Yodh, G. [University of California, Department of Physics and Astronomy, Irvine, CA (United States); Bay, R.; Filimonov, K.; Price, P.B.; Woschnagg, K. [University of California, Department of Physics, Berkeley, CA (United States); Beatty, J.J. [Ohio State University, Department of Physics, Center for Cosmology and Astro-Particle Physics, Columbus, OH (United States); Ohio State University, Department of Astronomy, Columbus, OH (United States); Becker Tjus, J.; Bos, F.; Eichmann, B.; Kroll, M.; Mandelartz, M.; Schoeneberg, S.; Tenholt, F. [Ruhr-Universitaet Bochum, Fakultaet fuer Physik and Astronomie, Bochum (Germany); Becker, K.H.; Bindig, D.; Helbing, K.; Hickford, S.; Hoffmann, R.; Kopper, S.; Naumann, U.; Obertacke Pollmann, A.; Omairat, A.; Posselt, J.; Soldin, D. [University of Wuppertal, Department of Physics, Wuppertal (Germany); BenZvi, S. [University of Rochester, Department of Physics and Astronomy, Rochester, NY (United States); Berghaus, P. [National Research Nuclear University, Moscow Engineering Physics Institute (MEPhI), Moscow (Russian Federation); Berley, D.; Blaufuss, E.; Cheung, E.; Felde, J.; Hellauer, R.; Hoffman, K.D.; Huelsnitz, W.; Maunu, R.; Olivas, A.; Schmidt, T.; Song, M.; Sullivan, G.W.; Wissing, H. [University of Maryland, Department of Physics, College Park, MD (United States); Besson, D.Z. [University of Kansas, Department of Physics and Astronomy, Lawrence, KS (United States); Binder, G.; Gerhardt, L.; Klein, S.R.; Miarecki, S.; Tatar, J. [University of California, Department of Physics, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Berkeley, CA (United States); and others

2016-10-15

We present the first IceCube search for a signal of dark matter annihilations in the Milky Way using all-flavour neutrino-induced particle cascades. The analysis focuses on the DeepCore sub-detector of IceCube, and uses the surrounding IceCube strings as a veto region in order to select starting events in the DeepCore volume. We use 329 live-days of data from IceCube operating in its 86-string configuration during 2011-2012. No neutrino excess is found, the final result being compatible with the background-only hypothesis. From this null result, we derive upper limits on the velocity-averaged self-annihilation cross-section, left angle σ{sub A}v right angle, for dark matter candidate masses ranging from 30 GeV up to 10 TeV, assuming both a cuspy and a flat-cored dark matter halo profile. For dark matter masses between 200 GeV and 10 TeV, the results improve on all previous IceCube results on left angle σ{sub A}v right angle, reaching a level of 10{sup -23} cm{sup 3} s {sup -1}, depending on the annihilation channel assumed, for a cusped NFW profile. The analysis demonstrates that all-flavour searches are competitive with muon channel searches despite the intrinsically worse angular resolution of cascades compared to muon tracks in IceCube. (orig.)

Deep-Sea Microbes: Linking Biogeochemical Rates to -Omics Approaches

Science.gov (United States)

Herndl, G. J.; Sintes, E.; Bayer, B.; Bergauer, K.; Amano, C.; Hansman, R.; Garcia, J.; Reinthaler, T.

2016-02-01

Over the past decade substantial progress has been made in determining deep ocean microbial activity and resolving some of the enigmas in understanding the deep ocean carbon flux. Also, metagenomics approaches have shed light onto the dark ocean's microbes but linking -omics approaches to biogeochemical rate measurements are generally rare in microbial oceanography and even more so for the deep ocean. In this presentation, we will show by combining metagenomics, -proteomics and biogeochemical rate measurements on the bulk and single-cell level that deep-sea microbes exhibit characteristics of generalists with a large genome repertoire, versatile in utilizing substrate as revealed by metaproteomics. This is in striking contrast with the apparently rather uniform dissolved organic matter pool in the deep ocean. Combining the different -omics approaches with metabolic rate measurements, we will highlight some major inconsistencies and enigmas in our understanding of the carbon cycling and microbial food web structure in the dark ocean.

Lepton-number-charged scalars and neutrino beamstrahlung

Science.gov (United States)

Berryman, Jeffrey M.; de Gouvêa, André; Kelly, Kevin J.; Zhang, Yue

2018-04-01

Experimentally, baryon number minus lepton number, B -L , appears to be a good global symmetry of nature. We explore the consequences of the existence of gauge-singlet scalar fields charged under B -L -dubbed lepton-number-charged scalars (LeNCSs)—and postulate that these couple to the standard model degrees of freedom in such a way that B -L is conserved even at the nonrenormalizable level. In this framework, neutrinos are Dirac fermions. Including only the lowest mass-dimension effective operators, some of the LeNCSs couple predominantly to neutrinos and may be produced in terrestrial neutrino experiments. We examine several existing constraints from particle physics, astrophysics, and cosmology to the existence of a LeNCS carrying B -L charge equal to two, and discuss the emission of LeNCSs via "neutrino beamstrahlung," which occurs every once in a while when neutrinos scatter off of ordinary matter. We identify regions of the parameter space where existing and future neutrino experiments, including the Deep Underground Neutrino Experiment, are at the frontier of searches for such new phenomena.

Direct cosmic ray muons and atmospheric neutrinos

International Nuclear Information System (INIS)

Ryazhskaya, O.G.; Volkova, L.V.; Zatsepin, G.T.

2005-01-01

A possible contribution of very short living particles (particles with life-time much shorter than that of charmed particles), for example, resonances, into cosmic ray muon and atmospheric neutrino fluxes (direct muons and neutrinos) is estimated. This contribution could become of the same order of magnitude as that from pions and kaons (conventional) already at energies of hundreds TeV and tens TeV for muons and muon neutrinos coming to the sea level in the vertical direction correspondingly. Of course, the estimation has quite a qualitative character and even it is quite arbitrary but it is necessary to keep this contribution in mind when studying EAS, cosmic ray muon component or trying to interpret data of experiments on cosmic neutrino searching at high energies

AFSC/RACE/GAP/Rooper: Deep sea coral and sponge distribution

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — As part of a series of ongoing research projects, the AFSC has been mapping and modeling the distribution of deep-sea coral and sponge communities throughout Alaska....

Alchemy or Science? Compromising Archaeology in the Deep Sea

Science.gov (United States)

Adams, Jonathan

2007-06-01

In the torrid debate between archaeology and treasure hunting, compromise is often suggested as the pragmatic solution, especially for archaeology carried out either in deep water or beyond the constraints that commonly regulate such activities in territorial seas. Both the wisdom and the need for such compromise have even been advocated by some archaeologists, particularly in forums such as the internet and conferences. This paper argues that such a compromise is impossible, not in order to fuel confrontation but simply because of the nature of any academic discipline. We can define what archaeology is in terms of its aims, theories, methods and ethics, so combining it with an activity founded on opposing principles must transform it into something else. The way forward for archaeology in the deep sea does not lie in a contradictory realignment of archaeology’s goals but in collaborative research designed to mesh with emerging national and regional research and management plans.

Captive rearing of the deep-sea coral Eguchipsammia fistula from the Red Sea demonstrates remarkable physiological plasticity

KAUST Repository

Roik, Anna Krystyna

2015-01-20

The presence of the cosmopolitan deep-sea coral Eguchipsammia fistula has recently been documented in the Red Sea, occurring in warm (>20 °C), oxygen- and nutrient-limited habitats. We collected colonies of this species from the central Red Sea that successfully resided in aquaria for more than one year. During this period the corals were exposed to increased oxygen levels and nutrition ad libitum unlike in their natural habitat. Specimens of long-term reared E. fistula colonies were incubated for 24 h and calcification (G) as well as respiration rates (R) were measured. In comparison to on-board measurements of G and R rates on freshly collected specimens, we found that G was increased while R was decreased. E. fistula shows extensive tissue growth and polyp proliferation in aquaculture and can be kept at conditions that notably differ from its natural habitat. Its ability to cope with rapid and prolonged changes in regard to prevailing environmental conditions indicates a wide physiological plasticity. This may explain in part the cosmopolitan distribution of this species and emphasizes its value as a deep-sea coral model to study mechanisms of acclimation and adaptation.

Captive rearing of the deep-sea coral Eguchipsammia fistula from the Red Sea demonstrates remarkable physiological plasticity

KAUST Repository

Roik, Anna Krystyna; Rö thig, Till; Roder, Cornelia; Muller, Paul Joachim; Voolstra, Christian R.

2015-01-01

The presence of the cosmopolitan deep-sea coral Eguchipsammia fistula has recently been documented in the Red Sea, occurring in warm (>20 °C), oxygen- and nutrient-limited habitats. We collected colonies of this species from the central Red Sea that successfully resided in aquaria for more than one year. During this period the corals were exposed to increased oxygen levels and nutrition ad libitum unlike in their natural habitat. Specimens of long-term reared E. fistula colonies were incubated for 24 h and calcification (G) as well as respiration rates (R) were measured. In comparison to on-board measurements of G and R rates on freshly collected specimens, we found that G was increased while R was decreased. E. fistula shows extensive tissue growth and polyp proliferation in aquaculture and can be kept at conditions that notably differ from its natural habitat. Its ability to cope with rapid and prolonged changes in regard to prevailing environmental conditions indicates a wide physiological plasticity. This may explain in part the cosmopolitan distribution of this species and emphasizes its value as a deep-sea coral model to study mechanisms of acclimation and adaptation.

Captive rearing of the deep-sea coral Eguchipsammia fistula from the Red Sea demonstrates remarkable physiological plasticity.

Science.gov (United States)

Roik, Anna; Röthig, Till; Roder, Cornelia; Müller, Paul J; Voolstra, Christian R

2015-01-01

The presence of the cosmopolitan deep-sea coral Eguchipsammia fistula has recently been documented in the Red Sea, occurring in warm (>20 °C), oxygen- and nutrient-limited habitats. We collected colonies of this species from the central Red Sea that successfully resided in aquaria for more than one year. During this period the corals were exposed to increased oxygen levels and nutrition ad libitum unlike in their natural habitat. Specimens of long-term reared E. fistula colonies were incubated for 24 h and calcification (G) as well as respiration rates (R) were measured. In comparison to on-board measurements of G and R rates on freshly collected specimens, we found that G was increased while R was decreased. E. fistula shows extensive tissue growth and polyp proliferation in aquaculture and can be kept at conditions that notably differ from its natural habitat. Its ability to cope with rapid and prolonged changes in regard to prevailing environmental conditions indicates a wide physiological plasticity. This may explain in part the cosmopolitan distribution of this species and emphasizes its value as a deep-sea coral model to study mechanisms of acclimation and adaptation.

Captive rearing of the deep-sea coral Eguchipsammia fistula from the Red Sea demonstrates remarkable physiological plasticity

Directory of Open Access Journals (Sweden)

Anna Roik

2015-01-01

Full Text Available The presence of the cosmopolitan deep-sea coral Eguchipsammia fistula has recently been documented in the Red Sea, occurring in warm (>20 °C, oxygen- and nutrient-limited habitats. We collected colonies of this species from the central Red Sea that successfully resided in aquaria for more than one year. During this period the corals were exposed to increased oxygen levels and nutrition ad libitum unlike in their natural habitat. Specimens of long-term reared E. fistula colonies were incubated for 24 h and calcification (G as well as respiration rates (R were measured. In comparison to on-board measurements of G and R rates on freshly collected specimens, we found that G was increased while R was decreased. E. fistula shows extensive tissue growth and polyp proliferation in aquaculture and can be kept at conditions that notably differ from its natural habitat. Its ability to cope with rapid and prolonged changes in regard to prevailing environmental conditions indicates a wide physiological plasticity. This may explain in part the cosmopolitan distribution of this species and emphasizes its value as a deep-sea coral model to study mechanisms of acclimation and adaptation.

Species distribution models of two critically endangered deep-sea octocorals reveal fishing impacts on vulnerable marine ecosystems in central Mediterranean Sea.

Science.gov (United States)

Lauria, V; Garofalo, G; Fiorentino, F; Massi, D; Milisenda, G; Piraino, S; Russo, T; Gristina, M

2017-08-14

Deep-sea coral assemblages are key components of marine ecosystems that generate habitats for fish and invertebrate communities and act as marine biodiversity hot spots. Because of their life history traits, deep-sea corals are highly vulnerable to human impacts such as fishing. They are an indicator of vulnerable marine ecosystems (VMEs), therefore their conservation is essential to preserve marine biodiversity. In the Mediterranean Sea deep-sea coral habitats are associated with commercially important crustaceans, consequently their abundance has dramatically declined due to the effects of trawling. Marine spatial planning is required to ensure that the conservation of these habitats is achieved. Species distribution models were used to investigate the distribution of two critically endangered octocorals (Funiculina quadrangularis and Isidella elongata) in the central Mediterranean as a function of environmental and fisheries variables. Results show that both species exhibit species-specific habitat preferences and spatial patterns in response to environmental variables, but the impact of trawling on their distribution differed. In particular F. quadrangularis can overlap with fishing activities, whereas I. elongata occurs exclusively where fishing is low or absent. This study represents the first attempt to identify key areas for the protection of soft and compact mud VMEs in the central Mediterranean Sea.

Molecular analyses reveal high levels of eukaryotic richness associated with enigmatic deep-sea protists (Komokiacea)

DEFF Research Database (Denmark)

Lecroq, Beatrice; Gooday, Andrew John; Cedhagen, Tomas

2009-01-01

Komokiaceans are testate agglutinated protists, extremely diverse and abundant in the deep sea. About 40 species are described and share the same main morpholog- ical feature: a test consisting of narrow branching tubules forming a complex system. In some species, the interstices between the tubu......Komokiaceans are testate agglutinated protists, extremely diverse and abundant in the deep sea. About 40 species are described and share the same main morpholog- ical feature: a test consisting of narrow branching tubules forming a complex system. In some species, the interstices between...... suggest strongly that komokiaceans, and probably many other large testate protists, provide a habitat structure for a large spectrum of eukaryotes, significantly contributing to maintaining the biodiversity of micro- and meiofaunal communities in the deep sea....

Installation of deep water sub-sea equipment

Energy Technology Data Exchange (ETDEWEB)

Pollack, Jack; Demian, Nabil [SBM-IMODCO Inc., Houston, TX (UNited States)

2004-07-01

Offshore oil developments are being planned in water depths exceeding 2000 m. Lowering and positioning large, heavy sub sea hardware, using conventional methods, presents new technical challenges in these ultra deep waters. In 3000 m a safe lift using conventional steel cables will require more capacity to support the cable self weight than the static payload. Adding dynamic loads caused by the motions of the surface vessel can quickly cause the safe capacity of the wire to be exceeded. Synthetic ropes now exist to greatly reduce the lowering line weight. The lower stiffness of these synthetic ropes aggravate the dynamic line tensions due to vessel motions and relatively little is known about the interaction of these ropes on the winches and sheaves required for pay-out and haul-in of these lines under dynamic load. Usage of conventional winches would damage the synthetic rope and risk the hardware being deployed. Reliable and economic installation systems that can operate from existing installation vessels are considered vital for ultra deep-water oil development. The paper describes a Deep Water Sub-Sea Hardware Deployment system consisting of a buoy with variable, pressure-balanced buoyancy, which is used to offset most of the payload weight as it is lowered. The buoyant capacity is controlled by air pumped into the tank from the surface vessel through a reinforced hose. The buoy and payload motion are isolated from the deployment line surface dynamics using a simple passive heave compensator mounted between the buoy and the bottom of the deployment rope. The system components, functionality and dynamic behavior are presented in the paper. (author)

76 FR 36511 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab; Amendment 3

Science.gov (United States)

2011-06-22

...-BA22 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab; Amendment 3 AGENCY... the Atlantic Deep-Sea Red Crab Fishery Management Plan (FMP) (Amendment 3), incorporating a draft... current trap limit regulations state that red crab may not be harvested from gear other than a marked red...

The Deep-Sea Microbial Community from the Amazonian Basin Associated with Oil Degradation

Directory of Open Access Journals (Sweden)

Mariana E. Campeão

2017-06-01

Full Text Available One consequence of oil production is the possibility of unplanned accidental oil spills; therefore, it is important to evaluate the potential of indigenous microorganisms (both prokaryotes and eukaryotes from different oceanic basins to degrade oil. The aim of this study was to characterize the microbial response during the biodegradation process of Brazilian crude oil, both with and without the addition of the dispersant Corexit 9500, using deep-sea water samples from the Amazon equatorial margin basins, Foz do Amazonas and Barreirinhas, in the dark and at low temperatures (4°C. We collected deep-sea samples in the field (about 2570 m below the sea surface, transported the samples back to the laboratory under controlled environmental conditions (5°C in the dark and subsequently performed two laboratory biodegradation experiments that used metagenomics supported by classical microbiological methods and chemical analysis to elucidate both taxonomic and functional microbial diversity. We also analyzed several physical–chemical and biological parameters related to oil biodegradation. The concomitant depletion of dissolved oxygen levels, oil droplet density characteristic to oil biodegradation, and BTEX concentration with an increase in microbial counts revealed that oil can be degraded by the autochthonous deep-sea microbial communities. Indigenous bacteria (e.g., Alteromonadaceae, Colwelliaceae, and Alcanivoracaceae, archaea (e.g., Halobacteriaceae, Desulfurococcaceae, and Methanobacteriaceae, and eukaryotic microbes (e.g., Microsporidia, Ascomycota, and Basidiomycota from the Amazonian margin deep-sea water were involved in biodegradation of Brazilian crude oil within less than 48-days in both treatments, with and without dispersant, possibly transforming oil into microbial biomass that may fuel the marine food web.

Deep-sea benthic footprint of the deepwater horizon blowout.

Directory of Open Access Journals (Sweden)

Paul A Montagna

Full Text Available The Deepwater Horizon (DWH accident in the northern Gulf of Mexico occurred on April 20, 2010 at a water depth of 1525 meters, and a deep-sea plume was detected within one month. Oil contacted and persisted in parts of the bottom of the deep-sea in the Gulf of Mexico. As part of the response to the accident, monitoring cruises were deployed in fall 2010 to measure potential impacts on the two main soft-bottom benthic invertebrate groups: macrofauna and meiofauna. Sediment was collected using a multicorer so that samples for chemical, physical and biological analyses could be taken simultaneously and analyzed using multivariate methods. The footprint of the oil spill was identified by creating a new variable with principal components analysis where the first factor was indicative of the oil spill impacts and this new variable mapped in a geographic information system to identify the area of the oil spill footprint. The most severe relative reduction of faunal abundance and diversity extended to 3 km from the wellhead in all directions covering an area about 24 km(2. Moderate impacts were observed up to 17 km towards the southwest and 8.5 km towards the northeast of the wellhead, covering an area 148 km(2. Benthic effects were correlated to total petroleum hydrocarbon, polycyclic aromatic hydrocarbons and barium concentrations, and distance to the wellhead; but not distance to hydrocarbon seeps. Thus, benthic effects are more likely due to the oil spill, and not natural hydrocarbon seepage. Recovery rates in the deep sea are likely to be slow, on the order of decades or longer.

Geo-neutrinos and earth's interior

International Nuclear Information System (INIS)

Fiorentini, Gianni; Lissia, Marcello; Mantovani, Fabio

2007-01-01

The deepest hole that has ever been dug is about 12 km deep. Geochemists analyze samples from the Earth's crust and from the top of the mantle. Seismology can reconstruct the density profile throughout all Earth, but not its composition. In this respect, our planet is mainly unexplored. Geo-neutrinos, the antineutrinos from the progenies of U, Th and 40 K decays in the Earth, bring to the surface information from the whole planet, concerning its content of natural radioactive elements. Their detection can shed light on the sources of the terrestrial heat flow, on the present composition, and on the origins of the Earth. Geo-neutrinos represent a new probe of our planet, which can be exploited as a consequence of two fundamental advances that occurred in the last few years: the development of extremely low background neutrino detectors and the progress on understanding neutrino propagation. We review the status and the prospects of the field

Major impacts of climate change on deep-sea benthic ecosystems

Directory of Open Access Journals (Sweden)

Andrew K. Sweetman

2017-02-01

Full Text Available The deep sea encompasses the largest ecosystems on Earth. Although poorly known, deep seafloor ecosystems provide services that are vitally important to the entire ocean and biosphere. Rising atmospheric greenhouse gases are bringing about significant changes in the environmental properties of the ocean realm in terms of water column oxygenation, temperature, pH and food supply, with concomitant impacts on deep-sea ecosystems. Projections suggest that abyssal (3000–6000 m ocean temperatures could increase by 1°C over the next 84 years, while abyssal seafloor habitats under areas of deep-water formation may experience reductions in water column oxygen concentrations by as much as 0.03 mL L–1 by 2100. Bathyal depths (200–3000 m worldwide will undergo the most significant reductions in pH in all oceans by the year 2100 (0.29 to 0.37 pH units. O2 concentrations will also decline in the bathyal NE Pacific and Southern Oceans, with losses up to 3.7% or more, especially at intermediate depths. Another important environmental parameter, the flux of particulate organic matter to the seafloor, is likely to decline significantly in most oceans, most notably in the abyssal and bathyal Indian Ocean where it is predicted to decrease by 40–55% by the end of the century. Unfortunately, how these major changes will affect deep-seafloor ecosystems is, in some cases, very poorly understood. In this paper, we provide a detailed overview of the impacts of these changing environmental parameters on deep-seafloor ecosystems that will most likely be seen by 2100 in continental margin, abyssal and polar settings. We also consider how these changes may combine with other anthropogenic stressors (e.g., fishing, mineral mining, oil and gas extraction to further impact deep-seafloor ecosystems and discuss the possible societal implications.

Velocity and Attenuation Profiles in the Monterey Deep-Sea Fan

Science.gov (United States)

1987-12-01

a. 11 o n i n and depth. Sol ’^ a 11 e i"i u a 11 o >) a i::> 1 n Ci sediment for each of the f i...i. n c t ion o f f r e q u e n c; y...estimate of sea floor depth was obtained from an oceano - graphic map of the Monterey fan (’Oceanographic Data of the Monterey Deep Sea Fan’, 1st

Biogenic Properties of Deep Waters from the Black Sea Reduction (Hydrogen Sulphide) Zone for Marine Algae

OpenAIRE

Polikarpov, Gennady G.; Lazorenko, Galina Е.; Тereschenko, Natalya N.

2015-01-01

Abstract Generalized data of biogenic properties investigations of the Black Sea deep waters from its reduction zone for marine algae are presented. It is shown on board and in laboratory that after pre-oxidation of hydrogen sulphide by intensive aeration of the deep waters lifted to the surface of the sea, they are ready to be used for cultivation of the Black Sea unicellular, planktonic, and multicellular, benthic, algae instead of artificial medium. Naturally balanced micro- and macroeleme...

Detectability of thermal neutrinos from binary neutron-star mergers and implications for neutrino physics

Science.gov (United States)

Kyutoku, Koutarou; Kashiyama, Kazumi

2018-05-01

We propose a long-term strategy for detecting thermal neutrinos from the remnant of binary neutron-star mergers with a future M-ton water-Cherenkov detector such as Hyper-Kamiokande. Monitoring ≳2500 mergers within ≲200 Mpc , we may be able to detect a single neutrino with a human time-scale operation of ≈80 Mtyears for the merger rate of 1 Mpc-3 Myr-1 , which is slightly lower than the median value derived by the LIGO-Virgo Collaboration with GW170817. Although the number of neutrino events is minimal, contamination from other sources of neutrinos can be reduced efficiently to ≈0.03 by analyzing only ≈1 s after each merger identified with gravitational-wave detectors if gadolinium is dissolved in the water. The contamination may be reduced further to ≈0.01 if we allow the increase of waiting time by a factor of ≈1.7 . The detection of even a single neutrino can pin down the energy scale of thermal neutrino emission from binary neutron-star mergers and could strongly support or disfavor formation of remnant massive neutron stars. Because the dispersion relation of gravitational waves is now securely constrained to that of massless particles with a corresponding limit on the graviton mass of ≲10-22 eV /c2 by binary black-hole mergers, the time delay of a neutrino from gravitational waves can be used to put an upper limit of ≲O (10 ) meV /c2 on the absolute neutrino mass in the lightest eigenstate. Large neutrino detectors will enhance the detectability, and, in particular, 5 Mt Deep-TITAND and 10 Mt MICA planned in the future will allow us to detect thermal neutrinos every ≈16 and 8 years, respectively, increasing the significance.

Characteristics of shock-associated fast-drift kilometric radio bursts

Science.gov (United States)

Macdowall, R. J.; Kundu, M. R.; Stone, R. G.

1987-01-01

The existence of a class of fast-drift, shock-associated (SA), kilometric radio bursts which occur at the time of metric type II emission and which are not entirely the kilometric continuation of metric type III bursts has been reported previously (Cane et al., 1981). In this paper unambiguous SA event criteria are established for the purpose of statistically comparing SA events with conventional kilometric type III bursts. Applying these criteria to all long-duration, fast-drift bursts observed by the ISEE-3 spacecraft during a 28-month interval, it is found that more than 70 percent of the events satisfying the criteria are associated with the radio signatures of coronal shocks. If a given event is associated with a metric type II or type IV burst, it is 13 times more likely to satisfy the SA criteria than an event associated only with metric type III activity.

Earth as a radio source: terrestrial kilometric radiation. Progress report

International Nuclear Information System (INIS)

Gurnett, D.A.

1974-02-01

Radio wave experiments on the IMP-6 and 8 satellites have shown that the earth emits very intense electromagnetic radiation in the frequency range from about 50 kHz to 500 kHz. A peak intensity the total power emitted in this frequency range is about 1 billion watts. The earth is, therefore, a very intense planetary radio source, with a total power output comparable to the decametric radio emission from Jupiter. This radio emission from the earth is referred to as terrestrial kilometric radiation. Terrestrial kilometric radiation appears to originate from low altitudes (less than 3.0 Re) in the auroral region. Possible mechanisms which can explain the generation and propagation of the terrestrial kilometric radiation are discussed. (U.S.)

Systems analysis for disposal of radioactive wastes in deep sea bottom

International Nuclear Information System (INIS)

Karpf, A.D.

1988-12-01

Part I of the report outlines substantial fundamentals and results that impart sufficient knowledge to understand the resepctive calculations, the influence of essential parameters and to allow unambiguous conclusions as regards the potential riks of a repository in the deep sea bottom. In addition, significant features of the developed programme are described and an overview of international cooperation in this field is given. The more detailed parts II and III deal with the actual repository in the sea sediment layer and its sea biosphere, respectively. (orig./DG) [de

76 FR 60379 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab; Amendment 3

Science.gov (United States)

2011-09-29

.... 100903433-1531-02] RIN 0648-BA22 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab... approved in Amendment 3 to the Atlantic Deep-Sea Red Crab Fishery Management Plan (FMP). The New England... ABC control rule.'' The NS1 guidelines further state that ``ABC may not exceed OFL,'' and that ``the...

Deep-Sea Bioluminescence Blooms after Dense Water Formation at the Ocean Surface

NARCIS (Netherlands)

Tamburini, C.; Canals, M.; de Madron, X.D.; Houpert, L.; Lefevre, D.; Martini, V.; D'Ortenzio, F.; Robert, A.; Testor, P.; Aguilar, J.A.; Al Samarai, I.; Albert, A.; Andre, M.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Jesus, A.C.A.; Astraatmadja, T.L.; Aubert, J.J.; Baret, B.; Basa, S.; Bertin, V.; Biagi, S.; Bigi, A.; Bigongiari, C.; Bogazzi, C.; Bou-Cabo, M.; Bouhou, B.; Bouwhuis, M.C.; Brunner, J.; Busto, J.; Camarena, F.; Capone, A.; Carloganu, C.; Carminati, G.; Carr, J.; Cecchini, S.; Charif, Z.; Charvis, P.; Chiarusi, T.; Circella, M.; Coniglione, R.; Costantini, H.; Coyle, P.; Curtil, C.; Decowski, P.; Dekeyser, I.; Deschamps, A.; Donzaud, C.; Dornic, D.; Dorosti, H.Q.; Drouhin, D.; Eberl, T.; Emanuele, U.; Ernenwein, J.P.; Escoffier, S.; Fermani, P.; Ferri, M.; Flaminio, V.; Folger, F.; Fritsch, U.; Fuda, J.L.; Galata, S.; Gay, P.; Giacomelli, G.; Giordano, V.; Gomez-Gonzalez, J.P.; Graf, K.; Guillard, G.; Halladjian, G.; Hallewell, G.; van Haren, H.; Hartman, J.; Heijboer, A.J.; Hello, Y.; Hernandez-Rey, J.J.; Herold, B.; Hossl, J.; Hsu, C.C.; De Jong, M.; Kadler, M.; Kalekin, O.; Kappes, A.; Katz, U.; Kavatsyuk, O.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kreykenbohm, I.; Kulikovskiy, V.; Lahmann, R.; Lamare, P.; Larosa, G.; Lattuada, D.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Mangano, S.; Marcelin, M.; Margiotta, A.; Martinez-Mora, J.A.; Meli, A.; Montaruli, T.; Moscoso, L.; Motz, H.; Neff, M.; Nezri, E.N.; Palioselitis, D.; Pavalas, G.E.; Payet, K.; Payre, P.; Petrovic, J.; Piattelli, P.; Picot-Clemente, N.; Popa, V.; Pradier, T.; Presani, E.; Racca, C.; Reed, C.; Riccobene, G.; Richardt, C.; Richter, R.; Riviere, C.; Roensch, K.; Rostovtsev, A.; Ruiz-Rivas, J.; Rujoiu, M.; Russo, V.G.; Salesa, F.; Sanchez-Losa, A.; Sapienza, P.; Schock, F.; Schuller, J.P.; Schussler, F.; Shanidze, R.; Simeone, F.; Spies, A.; Spurio, M.; Steijger, J.J.M.; Stolarczyk, T.; Taiuti, M.G.F.; Toscano, S.; Vallage, B.; Van Elewyck, V.; Vannoni, G.; Vecchi, M.; Vernin, P.; Wijnker, G.; Wilms, J.; de Wolf, E.; Yepes, H.; Zaborov, D.; Zornoza, J.D.; Zuniga, J.

2013-01-01

The deep ocean is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June

The secret to successful deep-sea invasion: does low temperature hold the key?

Directory of Open Access Journals (Sweden)

Kathryn E Smith

Full Text Available There is a general consensus that today's deep-sea biodiversity has largely resulted from recurrent invasions and speciations occurring through homogenous waters during periods of the Phanerozoic eon. Migrations likely continue today, primarily via isothermal water columns, such as those typical of Polar Regions, but the necessary ecological and physiological adaptations behind them are poorly understood. In an evolutionary context, understanding the adaptations, which allow for colonisation to high-pressure environments, may enable us to predict future events. In this investigation, we examine pressure tolerance during development, in the shallow-water neogastropod Buccinum undatum using thermally acclimated egg masses from temperate and sub-polar regions across the species range. Fossil records indicate neogastropods to have a deep-water origin, suggesting shallow-water species may be likely candidates for re-emergence into the deep sea. Our results show population level differences in physiological thresholds, which indicate low temperature acclimation to increase pressure tolerance. These findings imply this species is capable of deep-sea penetration through isothermal water columns prevailing at high latitudes. This study gives new insight into the fundamentals behind past and future colonisation events. Such knowledge is instrumental to understand better how changes in climate envelopes affect the distribution and radiation of species along latitudinal as well as bathymetric temperature gradients.

Postcolonial partnerships: deep sea research, media coverage and (inter)national narratives on the Galathea Deep Sea Expedition from 1950 to 1952.

Science.gov (United States)

Nielsen, Kristian Hvidtfelt

2010-03-01

The Danish Galathea Deep Sea Expedition between 1950 and 1952 combined scientific and official objectives with the production of national and international narratives distributed through the daily press and other media. Dispatched by the Danish government on a newly acquired naval ship, the expedition undertook groundbreaking deep sea research while also devoting efforts to showing the flag, public communication of science, and international cooperation. The expedition was conceived after the war as a way in which to rehabilitate Denmark's reputation internationally and to rebuild national pride. To this end, the expedition included an onboard press section reporting the expedition to the Danish public and to an international audience. The press section mediated the favourable, post-war and postcolonial image of Denmark as an internationalist, scientific, modernizing and civilizing nation for which the expedition planners and many others were hoping. The expedition, therefore, was highly relevant to, indeed fed on, the emerging internationalist agenda in Denmark's foreign policy. Bringing out these aspects of the historical context of the expedition, this paper adds important perspectives to our knowledge about the expedition in particular and, more generally, about scientific exploration in the immediate post-war and postcolonial period.

From deep-sea volcanoes to human pathogens: a conserved quorum-sensing signal in Epsilonproteobacteria.

Science.gov (United States)

Pérez-Rodríguez, Ileana; Bolognini, Marie; Ricci, Jessica; Bini, Elisabetta; Vetriani, Costantino

2015-05-01

Chemosynthetic Epsilonproteobacteria from deep-sea hydrothermal vents colonize substrates exposed to steep thermal and redox gradients. In many bacteria, substrate attachment, biofilm formation, expression of virulence genes and host colonization are partly controlled via a cell density-dependent mechanism involving signal molecules, known as quorum sensing. Within the Epsilonproteobacteria, quorum sensing has been investigated only in human pathogens that use the luxS/autoinducer-2 (AI-2) mechanism to control the expression of some of these functions. In this study we showed that luxS is conserved in Epsilonproteobacteria and that pathogenic and mesophilic members of this class inherited this gene from a thermophilic ancestor. Furthermore, we provide evidence that the luxS gene is expressed--and a quorum-sensing signal is produced--during growth of Sulfurovum lithotrophicum and Caminibacter mediatlanticus, two Epsilonproteobacteria from deep-sea hydrothermal vents. Finally, we detected luxS transcripts in Epsilonproteobacteria-dominated biofilm communities collected from deep-sea hydrothermal vents. Taken together, our findings indicate that the epsiloproteobacterial lineage of the LuxS enzyme originated in high-temperature geothermal environments and that, in vent Epsilonproteobacteria, luxS expression is linked to the production of AI-2 signals, which are likely produced in situ at deep-sea vents. We conclude that the luxS gene is part of the ancestral epsilonproteobacterial genome and represents an evolutionary link that connects thermophiles to human pathogens.

How can we identify and communicate the ecological value of deep-sea ecosystem services?

Science.gov (United States)

Jobstvogt, Niels; Townsend, Michael; Witte, Ursula; Hanley, Nick

2014-01-01

Submarine canyons are considered biodiversity hotspots which have been identified for their important roles in connecting the deep sea with shallower waters. To date, a huge gap exists between the high importance that scientists associate with deep-sea ecosystem services and the communication of this knowledge to decision makers and to the wider public, who remain largely ignorant of the importance of these services. The connectivity and complexity of marine ecosystems makes knowledge transfer very challenging, and new communication tools are necessary to increase understanding of ecological values beyond the science community. We show how the Ecosystem Principles Approach, a method that explains the importance of ocean processes via easily understandable ecological principles, might overcome this challenge for deep-sea ecosystem services. Scientists were asked to help develop a list of clear and concise ecosystem principles for the functioning of submarine canyons through a Delphi process to facilitate future transfers of ecological knowledge. These ecosystem principles describe ecosystem processes, link such processes to ecosystem services, and provide spatial and temporal information on the connectivity between deep and shallow waters. They also elucidate unique characteristics of submarine canyons. Our Ecosystem Principles Approach was successful in integrating ecological information into the ecosystem services assessment process. It therefore has a high potential to be the next step towards a wider implementation of ecological values in marine planning. We believe that successful communication of ecological knowledge is the key to a wider public support for ocean conservation, and that this endeavour has to be driven by scientists in their own interest as major deep-sea stakeholders.

Metabolic profiles of prokaryotic and eukaryotic communities in deep-sea sponge Neamphius huxleyi [corrected]. indicated by metagenomics.

Science.gov (United States)

Li, Zhi-Yong; Wang, Yue-Zhu; He, Li-Ming; Zheng, Hua-Jun

2014-01-27

The whole metabolism of a sponge holobiont and the respective contributions of prokaryotic and eukaryotic symbionts and their associations with the sponge host remain largely unclear. Meanwhile, compared with shallow water sponges, deep-sea sponges are rarely understood. Here we report the metagenomic exploration of deep-sea sponge Neamphius huxleyi [corrected] . at the whole community level. Metagenomic data showed phylogenetically diverse prokaryotes and eukaryotes in Neamphius huxleyi [corrected]. MEGAN and gene enrichment analyses indicated different metabolic potentials of prokaryotic symbionts from eukaryotic symbionts, especially in nitrogen and carbon metabolisms, and their molecular interactions with the sponge host. These results supported the hypothesis that prokaryotic and eukaryotic symbionts have different ecological roles and relationships with sponge host. Moreover, vigorous denitrification, and CO2 fixation by chemoautotrophic prokaryotes were suggested for this deep-sea sponge. The study provided novel insights into the respective potentials of prokaryotic and eukaryotic symbionts and their associations with deep-sea sponge Neamphius huxleyi [corrected].

Deep and intermediate mediterranean water in the western Alboran Sea

Science.gov (United States)

Parrilla, Gregorio; Kinder, Thomas H.; Preller, Ruth H.

1986-01-01

Hydrographic and current meter data, obtained during June to October 1982, and numerical model experiments are used to study the distribution and flow of Mediterranean waters in the western Alboran Sea. The Intermediate Water is more pronounced in the northern three-fourths of the sea, but its distribution is patchy as manifested by variability of the temperature and salinity maxima at scales ≤10 km. Current meters in the lower Intermediate Water showed mean flow toward the Strait at 2 cm s -1. A reversal of this flow lasted about 2 weeks. A rough estimate of the mean westward Intermediate Water transport was 0.4 × 10 6 m 3 s -1, about one-third of the total outflow, so that the best estimates of the contributions of traditionally defined Intermediate Water and Deep Water account for only about one-half of the total outflow. The Deep Water was uplifted against the southern continental slope from Alboran Island (3°W) to the Strait. There was also a similar but much weaker banking against the Spanish slope, but a deep current record showed that the eastward recirculation implied by this banking is probably intermittent. Two-layer numerical model experiments simulated the Intermediate Water flow with a flat bottom and the Deep Water with realistic bottom topography. Both experiments replicated the major circulation features, and the Intermediate Water flow was concentrated in the north because of rotation and the Deep Water flow in the south because of topographic control.

STATUS OF THE US LONG BASELINE NEUTRINO EXPERIMENT STUDY.

Energy Technology Data Exchange (ETDEWEB)

BISHAI,M.

2006-09-21

The US Long Baseline Neutrino Experiment Study was commissioned jointly by Brookhaven National Laboratory and Fermi National Accelerator Laboratory to investigate the potential for future U.S. based long baseline neutrino oscillation experiments beyond the currently planned program. The Study focused on MW class convention at neutrino beams that can be produced at Fermilab or BNL. The experimental baselines are based on two possible detector locations: (1) off-axis to the existing Fermilab NuMI beamline at baselines of 700 to 810 km and (2) NSF's proposed future Deep Underground Science and Engineering Laboratory (DUSEL) at baselines greater than 1000 km. Two detector technologies are considered: a megaton class Water Cherenkov detector deployed deep underground at a DUSEL site, or a 100kT Liquid Argon Time-Projection Chamber (TPC) deployed on the surface at any of the proposed sites. The physics sensitivities of the proposed experiments are summarized. We find that conventional horn focused wide-band neutrino beam options from Fermilab or BNL aimed at a massive detector with a baseline of > 1000 km have the best sensitivity to CP violation and the neutrino mass hierarchy for values of the mixing angle {theta}{sub 13} down to 2.2{sup o}.

Difference of nitrogen-cycling microbes between shallow bay and deep-sea sediments in the South China Sea.

Science.gov (United States)

Yu, Tiantian; Li, Meng; Niu, Mingyang; Fan, Xibei; Liang, Wenyue; Wang, Fengping

2018-01-01

In marine sediments, microorganisms are known to play important roles in nitrogen cycling; however, the composition and quantity of microbes taking part in each process of nitrogen cycling are currently unclear. In this study, two different types of marine sediment samples (shallow bay and deep-sea sediments) in the South China Sea (SCS) were selected to investigate the microbial community involved in nitrogen cycling. The abundance and composition of prokaryotes and seven key functional genes involved in five processes of the nitrogen cycle [nitrogen fixation, nitrification, denitrification, dissimilatory nitrate reduction to ammonium (DNRA), and anaerobic ammonia oxidation (anammox)] were presented. The results showed that a higher abundance of denitrifiers was detected in shallow bay sediments, while a higher abundance of microbes involved in ammonia oxidation, anammox, and DNRA was found in the deep-sea sediments. Moreover, phylogenetic differentiation of bacterial amoA, nirS, nosZ, and nrfA sequences between the two types of sediments was also presented, suggesting environmental selection of microbes with the same geochemical functions but varying physiological properties.

Neutrino fluxes from the Galactic plane and the ANTARES limit

Directory of Open Access Journals (Sweden)

Fusco Luigi Antonio

2016-01-01

Full Text Available The existence of cosmic neutrinos has been reported by the IceCube Collaboration. Though this measurement is consistent with an isotropic neutrino flux, a sub-dominant galactic component coming from extended regions such as the Galactic Plane cannot be excluded. The ANTARES detector, located in the Mediterranean Sea, is currently the largest and longest operated under-water neutrino telescope; its effective area and good exposure to the Southern Sky allow to constrain an enhanced muon neutrino emission from extended sources such as the Galactic Plane. ANTARES data from 2007 to 2013 have been analysed and upper limits on the neutrino production from the central region of our galaxy have been set.

Deep-Diving California Sea Lions: Are They Pushing Their Physiological Limit

Science.gov (United States)

2015-09-30

highly variable. Venous oxygen content can actually increase during short duration dives. This suggests very little muscle blood flow and evven the use...the sea lion, the emperor penguin (Aptenodytes forsteri), another animal that dives on inspiration with a large respiratory O2 store, also can...in deep-diving emperor penguins (Wright et al. 2014), and in deep-diving bottlenose dolphins (Tursiops truncatus), which also dive on inspiration

Neutrino scattering physics with the SHiP Experiment

CERN Document Server

AUTHOR|(CDS)2083090

2015-01-01

SHiP (Search for Hidden Particles) is a new general purpose fixed target facility, proposed at the CERN SPS accelerator. In its initial phase the 400 GeV protons beam will be dumped on a heavy target with the aim of integrating 2 × 1020 pot in five years. A dedicated detector downstream the target will allow to probe a variety of models with the light long-lived exotic particles and masses below O(10) GeV/c2. Another dedicated detector will allow the study of active neutrino cross-sections and angular distributions. In particular, the neutrino deep-inelastic cross-sections will be performed with a statistics 1000 times larger than currently available, with the extraction of the F4 and F5 structure functions, never measured so far. Tau neutrinos will be distinguished by anti-neutrinos, thus providing the first observation of the tau anti-neutrino. With muon neutrinos it will be possible to study the strangeness content of the nucleon.

Neutrino scattering physics with the SHiP Experiment

CERN Document Server

Di Crescenzo, Antonia

2016-01-01

SHiP (Search for Hidden Particles) is a new general purpose fixed target facility, proposed at the CERN SPS accelerator. In its initial phase the 400 GeV protons beam will be dumped on a heavy target with the aim of integrating $2 \\times 10^{20}$ pot in five years. A dedicated detector downstream the target will allow to probe a variety of models with the light long-lived exotic particles and masses below O(10) GeV/c2. Another dedicated detector will allow the study of active neutrino cross-sections and angular distributions. In particular, the neutrino deep-inelastic cross-sections will be performed with a statistics 1000 times larger than currently available, with the extraction of the F4 and F5 structure functions, never measured so far. Tau neutrinos will be distinguished by anti-neutrinos, thus providing the first observation of the tau anti-neutrino. With muon neutrinos it will be possible to study the strangeness content of the nucleon.

Genetic homogeneity in the deep-sea grenadier Macrourus berglax across the North Atlantic Ocean

Science.gov (United States)

Coscia, Ilaria; Castilho, Rita; Massa-Gallucci, Alexia; Sacchi, Carlotta; Cunha, Regina L.; Stefanni, Sergio; Helyar, Sarah J.; Knutsen, Halvor; Mariani, Stefano

2018-02-01

Paucity of data on population structure and connectivity in deep sea species remains a major obstacle to their sustainable management and conservation in the face of ever increasing fisheries pressure and other forms of impacts on deep sea ecosystems. The roughhead grenadier Macrourus berglax presents all the classical characteristics of a deep sea species, such as slow growth and low fecundity, which make them particularly vulnerable to anthropogenic impact, due to their low resilience to change. In this study, the population structure of the roughhead grenadier is investigated throughout its geographic distribution using two sets of molecular markers: a partial sequence of the Control Region of mitochondrial DNA and species-specific microsatellites. No evidence of significant structure was found throughout the North Atlantic, with both sets of molecular markers yielding the same results of overall homogeneity. We posit two non-mutually exclusive scenarios that can explain such outcome: i) substantial high gene flow among locations, possibly maintained by larval stages, ii) very large effective size of post-glacially expanded populations. The results can inform management strategies in this by-caught species, and contribute to the broader issue of biological connectivity in the deep ocean.

Search for high energy cosmic neutrino point sources with ANTARES

International Nuclear Information System (INIS)

Halladjian, G.

2010-01-01

The aim of this thesis is the search for high energy cosmic neutrinos emitted by point sources with the ANTARES neutrino telescope. The detection of high energy cosmic neutrinos can bring answers to important questions such as the origin of cosmic rays and the γ-rays emission processes. In the first part of the thesis, the neutrino flux emitted by galactic and extragalactic sources and the number of events which can be detected by ANTARES are estimated. This study uses the measured γ-ray spectra of known sources taking into account the γ-ray absorption by the extragalactic background light. In the second part of the thesis, the absolute pointing of the ANTARES telescope is evaluated. Being located at a depth of 2475 m in sea water, the orientation of the detector is determined by an acoustic positioning system which relies on low and high frequency acoustic waves measurements between the sea surface and the bottom. The third part of the thesis is a search for neutrino point sources in the ANTARES data. The search algorithm is based on a likelihood ratio maximization method. It is used in two search strategies; 'the candidate sources list strategy' and 'the all sky search strategy'. Analysing 2007+2008 data, no discovery is made and the world's best upper limits on neutrino fluxes from various sources in the Southern sky are established. (author)

Deep-sea benthic community and environmental impact assessment at the Atlantic Frontier

Science.gov (United States)

Gage, John D.

2001-05-01

The seabed community provides a sensitive litmus for environmental change. North Sea analysis of benthic populations provides an effective means for monitoring impacts from man's interventions, such as offshore oil exploitation and fishing, against baseline knowledge of the environment. Comparable knowledge of the benthic biology in the deep waters of the Atlantic Frontier beyond the N.E. Atlantic shelf edge is poorly developed. But uncertainties should not encourage assumptions and extrapolations from the better-known conditions on the continental shelf. While sampling at present still provides the best means to assess the health of the deepwater benthic habitat, protocols developed for deep-sea fauna should be applied. These are necessary because of (a) lower faunal densities, (b) higher species richness, (c) smaller body size, and (d) to ensure comparability with other deep-sea data. As in the North Sea, species richness and relative abundance can be analysed from quantitative samples in order to detect impacts. But analysis based on taxonomic sufficiency above species level is premature, even if arguably possible for coastal communities. Measures also need to ensure identifications are not forced to more familiar coastal species without proper study. Species-level analysis may be applied to seabed photographs of megafauna in relation to data on bottom environment, such as currents and the sediment, to monitor the health of the deep-water community. Although the composition of higher taxa in the benthic community is broadly similar to soft sediments on the shelf, concordance in sensitivities is speculative. Moreover, new organisms occur, such as giant protozoan xenophyophores, unknown on the continental shelf, whose sensitivities remain conjectural. Past knowledge of the benthic biology of the deep-water areas off Scotland is based on scattered stations and some more focussed, multidisciplinary studies, and should be significantly augmented by the results from

Volcanism and Tectonics of the Central Deep Basin, Sea of Japan

Science.gov (United States)

Lelikov, E. P.; Emelyanova, T. A.; Pugachev, A. A.

2018-01-01

The paper presents the results of a study on the geomorphic structure, tectonic setting, and volcanism of the volcanoes and volcanic ridges in the deep Central Basin of the Sea of Japan. The ridges rise 500-600 m above the acoustic basement of the basin. These ridges were formed on fragments of thinned continental crust along deep faults submeridionally crossing the Central Basin and the adjacent continental part of the Primorye. The morphostructures of the basin began to submerge below sea level in the Middle Miocene and reached their contemporary positions in the Pliocene. Volcanism in the Central Basin occurred mostly in the Middle Miocene-Pliocene and formed marginal-sea basaltoids with OIB (ocean island basalt) geochemical signatures indicating the lower-mantle plume origin of these rocks. The OIB signatures of basaltoids tend to be expressed better in the eastern part of the Central Basin, where juvenile oceanic crust has developed. The genesis of this crust is probably related to rising and melting of the Pacific superplume apophyse.

Global Marine Science and Carlsberg - The Golden Connections of Johannes Schmidt (1877-1933) (Med dansksproget resume)

DEFF Research Database (Denmark)

Poulsen, Bo

for the Exploration of the Sea (ICES), the Danish state and several private companies. Launching 26 oceangoing expeditions Schmidt made landmark discoveries such as the breeding ground for the Atlantic eel in the Sargasso Sea. The scientific frontier was pushed literally kilometres into the deep sea and across...

Global Marine Science and Carlsberg

DEFF Research Database (Denmark)

Poulsen, Bo

for the Exploration of the Sea (ICES), the Danish state and several private companies. Launching 26 oceangoing expeditions Schmidt made landmark discoveries such as the breeding ground for the Atlantic eel in the Sargasso Sea. The scientific frontier was pushed literally kilometres into the deep sea and across...

Charm-Quark Production in Deep-Inelastic Neutrino Scattering at Next-to-Next-to-Leading Order in QCD.

Science.gov (United States)

Berger, Edmond L; Gao, Jun; Li, Chong Sheng; Liu, Ze Long; Zhu, Hua Xing

2016-05-27

We present a fully differential next-to-next-to-leading order calculation of charm-quark production in charged-current deep-inelastic scattering, with full charm-quark mass dependence. The next-to-next-to-leading order corrections in perturbative quantum chromodynamics are found to be comparable in size to the next-to-leading order corrections in certain kinematic regions. We compare our predictions with data on dimuon production in (anti)neutrino scattering from a heavy nucleus. Our results can be used to improve the extraction of the parton distribution function of a strange quark in the nucleon.

A modified likelihood-method to search for point-sources in the diffuse astrophysical neutrino-flux in IceCube

Energy Technology Data Exchange (ETDEWEB)

Reimann, Rene; Haack, Christian; Leuermann, Martin; Raedel, Leif; Schoenen, Sebastian; Schimp, Michael; Wiebusch, Christopher [III. Physikalisches Institut, RWTH Aachen (Germany); Collaboration: IceCube-Collaboration

2015-07-01

IceCube, a cubic-kilometer sized neutrino detector at the geographical South Pole, has recently measured a flux of high-energy astrophysical neutrinos. Although this flux has now been observed in multiple analyses, no point sources or source classes could be identified yet. Standard point source searches test many points in the sky for a point source of astrophysical neutrinos individually and therefore produce many trials. Our approach is to additionally use the measured diffuse spectrum to constrain the number of possible point sources and their properties. Initial studies of the method performance are shown.

JAMSTEC E-library of Deep-sea Images (J-EDI) Realizes a Virtual Journey to the Earth's Unexplored Deep Ocean

Science.gov (United States)

Sasaki, T.; Azuma, S.; Matsuda, S.; Nagayama, A.; Ogido, M.; Saito, H.; Hanafusa, Y.

2016-12-01

The Japan Agency for Marine-Earth Science and Technology (JAMSTEC) archives a large amount of deep-sea research videos and photos obtained by JAMSTEC's research submersibles and vehicles with cameras. The web site "JAMSTEC E-library of Deep-sea Images : J-EDI" (http://www.godac.jamstec.go.jp/jedi/e/) has made videos and photos available to the public via the Internet since 2011. Users can search for target videos and photos by keywords, easy-to-understand icons, and dive information at J-EDI because operating staffs classify videos and photos as to contents, e.g. living organism and geological environment, and add comments to them.Dive survey data including videos and photos are not only valiant academically but also helpful for education and outreach activities. With the aim of the improvement of visibility for broader communities, we added new functions of 3-dimensional display synchronized various dive survey data with videos in this year.New Functions Users can search for dive survey data by 3D maps with plotted dive points using the WebGL virtual map engine "Cesium". By selecting a dive point, users can watch deep-sea videos and photos and associated environmental data, e.g. water temperature, salinity, rock and biological sample photos, obtained by the dive survey. Users can browse a dive track visualized in 3D virtual spaces using the WebGL JavaScript library. By synchronizing this virtual dive track with videos, users can watch deep-sea videos recorded at a point on a dive track. Users can play an animation which a submersible-shaped polygon automatically traces a 3D virtual dive track and displays of dive survey data are synchronized with tracing a dive track. Users can directly refer to additional information of other JAMSTEC data sites such as marine biodiversity database, marine biological sample database, rock sample database, and cruise and dive information database, on each page which a 3D virtual dive track is displayed. A 3D visualization of a dive

Ship Track for Deep Sea Medicines 2003 - Office of Ocean Exploration

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Ship track of the Ronald H. Brown during the "Deep Sea Medicines 2003: Exploring the Gulf of Mexico" expedition sponsored by the National Oceanic and Atmospheric...

Clones or clans: the genetic structure of a deep-sea sponge, Aphrocallistes vastus, in unique sponge reefs of British Columbia, Canada.

Science.gov (United States)

Brown, Rachel R; Davis, Corey S; Leys, Sally P

2017-02-01

Understanding patterns of reproduction, dispersal and recruitment in deep-sea communities is increasingly important with the need to manage resource extraction and conserve species diversity. Glass sponges are usually found in deep water (>1000 m) worldwide but form kilometre-long reefs on the continental shelf of British Columbia and Alaska that are under threat from trawling and resource exploration. Due to their deep-water habitat, larvae have not yet been found and the level of genetic connectivity between reefs and nonreef communities is unknown. The genetic structure of Aphrocallistes vastus, the primary reef-building species in the Strait of Georgia (SoG) British Columbia, was studied using single nucleotide polymorphisms (SNPs). Pairwise comparisons of multilocus genotypes were used to assess whether sexual reproduction is common. Structure was examined 1) between individuals in reefs, 2) between reefs and 3) between sites in and outside the SoG. Sixty-seven SNPs were genotyped in 91 samples from areas in and around the SoG, including four sponge reefs and nearby nonreef sites. The results show that sponge reefs are formed through sexual reproduction. Within a reef and across the SoG basin, the genetic distance between individuals does not vary with geographic distance (r = -0.005 to 0.014), but populations within the SoG basin are genetically distinct from populations in Barkley Sound, on the west coast of Vancouver Island. Population structure was seen across all sample sites (global F ST  = 0.248), especially between SoG and non-SoG locations (average pairwise F ST  = 0.251). Our results suggest that genetic mixing occurs across sponge reefs via larvae that disperse widely. © 2016 John Wiley & Sons Ltd.

Metagenomic Signatures of Microbial Communities in Deep-Sea Hydrothermal Sediments of Azores Vent Fields.

Science.gov (United States)

Cerqueira, Teresa; Barroso, Cristina; Froufe, Hugo; Egas, Conceição; Bettencourt, Raul

2018-01-21

The organisms inhabiting the deep-seafloor are known to play a crucial role in global biogeochemical cycles. Chemolithoautotrophic prokaryotes, which produce biomass from single carbon molecules, constitute the primary source of nutrition for the higher organisms, being critical for the sustainability of food webs and overall life in the deep-sea hydrothermal ecosystems. The present study investigates the metabolic profiles of chemolithoautotrophs inhabiting the sediments of Menez Gwen and Rainbow deep-sea vent fields, in the Mid-Atlantic Ridge. Differences in the microbial community structure might be reflecting the distinct depth, geology, and distance from vent of the studied sediments. A metagenomic sequencing approach was conducted to characterize the microbiome of the deep-sea hydrothermal sediments and the relevant metabolic pathways used by microbes. Both Menez Gwen and Rainbow metagenomes contained a significant number of genes involved in carbon fixation, revealing the largely autotrophic communities thriving in both sites. Carbon fixation at Menez Gwen site was predicted to occur mainly via the reductive tricarboxylic acid cycle, likely reflecting the dominance of sulfur-oxidizing Epsilonproteobacteria at this site, while different autotrophic pathways were identified at Rainbow site, in particular the Calvin-Benson-Bassham cycle. Chemolithotrophy appeared to be primarily driven by the oxidation of reduced sulfur compounds, whether through the SOX-dependent pathway at Menez Gwen site or through reverse sulfate reduction at Rainbow site. Other energy-yielding processes, such as methane, nitrite, or ammonia oxidation, were also detected but presumably contributing less to chemolithoautotrophy. This work furthers our knowledge of the microbial ecology of deep-sea hydrothermal sediments and represents an important repository of novel genes with potential biotechnological interest.

How can we identify and communicate the ecological value of deep-sea ecosystem services?

Directory of Open Access Journals (Sweden)

Niels Jobstvogt

Full Text Available Submarine canyons are considered biodiversity hotspots which have been identified for their important roles in connecting the deep sea with shallower waters. To date, a huge gap exists between the high importance that scientists associate with deep-sea ecosystem services and the communication of this knowledge to decision makers and to the wider public, who remain largely ignorant of the importance of these services. The connectivity and complexity of marine ecosystems makes knowledge transfer very challenging, and new communication tools are necessary to increase understanding of ecological values beyond the science community. We show how the Ecosystem Principles Approach, a method that explains the importance of ocean processes via easily understandable ecological principles, might overcome this challenge for deep-sea ecosystem services. Scientists were asked to help develop a list of clear and concise ecosystem principles for the functioning of submarine canyons through a Delphi process to facilitate future transfers of ecological knowledge. These ecosystem principles describe ecosystem processes, link such processes to ecosystem services, and provide spatial and temporal information on the connectivity between deep and shallow waters. They also elucidate unique characteristics of submarine canyons. Our Ecosystem Principles Approach was successful in integrating ecological information into the ecosystem services assessment process. It therefore has a high potential to be the next step towards a wider implementation of ecological values in marine planning. We believe that successful communication of ecological knowledge is the key to a wider public support for ocean conservation, and that this endeavour has to be driven by scientists in their own interest as major deep-sea stakeholders.

Phosphate solubilizing bacteria: Comparison between coastal and deep sea sediments

Digital Repository Service at National Institute of Oceanography (India)

Biche, S.; Pandey, S.; Gonsalves, M.J.B.D.; Das, A.; Mascarenhas-Pereira, M.B.L.; LokaBharathi, P.A.

in the CIB sediments (r=0.59) than in the coastal sediments (r= 0.22). It is apparent that the enzyme activity in the coastal sediments could be more for P mobilization and in the oligotrophic deep sea it could be both for P and C mobilization....

Biological responses to disturbance from simulated deep-sea polymetallic nodulemining

NARCIS (Netherlands)

Jones, D.O.B.; Kaiser, S.; Sweetman, A.K.; Smith, C.R.; Menot, L.; Vink, A.; Trueblood, D.; Greinert, J.; Billett, D.S.M.; Martinez Arbizu, P.; Radziejewska, T.; Singh, R.; Ingole, B.; Stratmann, T.; Simon-Lledó, E.; Durden, J.M.; Clack, M.R.

2017-01-01

Commercial-scale mining for polymetallic nodules could have a major impact on the deepseaenvironment, but the effects of these mining activities on deep-sea ecosystems are verypoorly known. The first commercial test mining for polymetallic nodules was carried out in1970. Since then a number of

Turbidites and Benthic Faunal Succession in the Deep Sea: An Ecological Paradox

National Research Council Canada - National Science Library

Young, David

2001-01-01

Characteristics of benthic faunal succession following turbidity flows in the deep sea will vary according to the composition of turbidite materials, the spatial scales of deposition, the structure...

IceCube Gen2. The next-generation neutrino observatory for the South Pole

Energy Technology Data Exchange (ETDEWEB)

Santen, Jakob van [DESY, Zeuthen (Germany); Collaboration: IceCube-Collaboration

2016-07-01

The IceCube Neutrino Observatory is a cubic-kilometer Cherenkov telescope buried in the ice sheet at the South Pole that detects neutrinos of all flavors with energies from tens of GeV to several PeV. The instrument provided the first measurement of the flux of high-energy astrophysical neutrinos, opening a new window to the TeV universe. At the other end of its sensitivity range, IceCube has provided precision measurements of neutrino oscillation parameters that are competitive with dedicated accelerator-based experiments. Here we present design studies for IceCube Gen2, the next-generation neutrino observatory for the South Pole. Instrumenting a volume of more that 5 km{sup 3} with over 100 new strings, IceCube Gen2 will have substantially greater sensitivity to high-energy neutrinos than current-generation instruments. PINGU, a dense infill array, will lower the energy threshold of the inner detector region to 4 GeV, allowing a determination of the neutrino mass hierarchy. On the surface, a large air shower detector will veto high-energy atmospheric muons and neutrinos from the southern hemisphere, enhancing the reach of astrophysical neutrino searches. With its versatile instrumentation, the IceCube Gen2 facility will allow us to explore the neutrino sky with unprecedented sensitivity, providing new constraints on the sources of the highest-energy cosmic rays, and yield precision data on the mixing and mass ordering of neutrinos.

High Acidification Rate of Norwegian Sea Revealed by Boron Isotopes in the Deep-Sea Coral Madrepora Oculata

Science.gov (United States)

Gonzalez, C.; Douville, E.; Hall-Spencer, J.; Montagna, P.; Louvat, P.; Gaillardet, J.; Frank, N.; Bordier, L.; Juillet-Leclerc, A.

2012-12-01

Ocean acidification and global warming due to the increase of anthropogenic CO2 are major threats for marine calcifying organisms, such as deep-sea corals, particularly in high-latitude regions. In order to evaluate the current anthropogenic perturbation and to properly assess the impacts and responses of calcifiers to previous changes in pH it is critical to investigate past changes of the seawater carbonate system. Unfortunately, current instrumental records of oceanic pH are limited, covering only a few decades. Scleractinian coral skeletons record chemical parameters of the seawater in which they grow. However, pH variability over multidecadal timescales remains largely unknown in intermediate and deep seawater masses. Here we present a study that highlights the potential of deep-sea-corals to overcome the lack of long-term pH records and that emphasizes a rapid acidification of high latitude subsurface waters of Norwegian Sea during the past decades. We have reconstructed seawater pH and temperature from a well dated deep-sea coral specimen Madrepora oculata collected alive from Røst reef in Norwegian Sea (67°N, 9°E, 340 m depth). This large branching framework forming coral species grew its skeleton over more than four decades determined using AMS 14C and 210Pb dating (Sabatier et al. 2012). B-isotopes and Li/Mg ratios yield an acidification rate of about -0.0030±0.0008 pH-unit.year-1 and a warming of 0.3°C during the past four decades (1967-2007). Overall our reconstruction technique agrees well with previous pH calculations (Hönisch et al., 2007 vs. Trotter et al., 2011 and McCulloch et al., 2012, i.e. the iterative method), but additional corrections are here applied using stable isotope correlations (O, C, B) to properly address kinetic fractionation of boron isotopes used for pH reconstruction. The resulting pH curve strongly anti-correlates with the annual NAO index, which further strengthens our evidence for the ocean acidification rate

Syllidae (Annelida: Phyllodocida) from the deep Mediterranean Sea, with the description of three new species.

Science.gov (United States)

Langeneck, Joachim; Musco, Luigi; Busoni, Giulio; Conese, Ilaria; Aliani, Stefano; Castelli, Alberto

2018-01-03

Despite almost two centuries of research, the diversity of Mediterranean deep-sea environments remain still largely unexplored. This is particularly true for the polychaete family Syllidae. We report herein 14 species; among them, we describe Erinaceusyllis barbarae n. sp., Exogone sophiae n. sp. and Prosphaerosyllis danovaroi n. sp. and report Parexogone wolfi San Martín, 1991, Exogone lopezi San Martín, Ceberio Aguirrezabalaga, 1996 and Anguillosyllis Day, 1963 for the first time from the Western Mediterranean, the latter based on a single individual likely belonging to an undescribed species. Moreover, we re-establish Syllis profunda Cognetti, 1955 based on type and new material. Present data, along with a critical analysis of available literature, show that Syllidae are highly diverse in deep Mediterranean environments, even though they are rarely reported, probably due to the scarce number of studies devoted to the size-fraction of benthos including deep-sea syllids. Most deep-sea Syllidae have wide distributions, which do not include shallow-waters. 100 m depth apparently represents the boundary between the assemblages dominated by generalist shallow water syllids like Exogone naidina Ørsted, 1843 and Syllis parapari San Martín López, 2000, and those deep-water assemblages characterised by strictly deep-water species like Parexogone campoyi San Martín, Ceberio Aguirrezabalaga, 1996, Parexogone wolfi San Martín, 1991 and Syllis sp. 1 (= Langerhansia caeca Katzmann, 1973).

Fungal diversity in deep-sea sediments of a hydrothermal vent system in the Southwest Indian Ridge

Science.gov (United States)

Xu, Wei; Gong, Lin-feng; Pang, Ka-Lai; Luo, Zhu-Hua

2018-01-01

Deep-sea hydrothermal sediment is known to support remarkably diverse microbial consortia. In deep sea environments, fungal communities remain less studied despite their known taxonomic and functional diversity. High-throughput sequencing methods have augmented our capacity to assess eukaryotic diversity and their functions in microbial ecology. Here we provide the first description of the fungal community diversity found in deep sea sediments collected at the Southwest Indian Ridge (SWIR) using culture-dependent and high-throughput sequencing approaches. A total of 138 fungal isolates were cultured from seven different sediment samples using various nutrient media, and these isolates were identified to 14 fungal taxa, including 11 Ascomycota taxa (7 genera) and 3 Basidiomycota taxa (2 genera) based on internal transcribed spacers (ITS1, ITS2 and 5.8S) of rDNA. Using illumina HiSeq sequencing, a total of 757,467 fungal ITS2 tags were recovered from the samples and clustered into 723 operational taxonomic units (OTUs) belonging to 79 taxa (Ascomycota and Basidiomycota contributed to 99% of all samples) based on 97% sequence similarity. Results from both approaches suggest that there is a high fungal diversity in the deep-sea sediments collected in the SWIR and fungal communities were shown to be slightly different by location, although all were collected from adjacent sites at the SWIR. This study provides baseline data of the fungal diversity and biogeography, and a glimpse to the microbial ecology associated with the deep-sea sediments of the hydrothermal vent system of the Southwest Indian Ridge.

Palynofacies reveal fresh terrestrial organic matter inputs in the terminal lobes of the Congo deep-sea fan

Science.gov (United States)

Schnyder, Johann; Stetten, Elsa; Baudin, François; Pruski, Audrey M.; Martinez, Philippe

2017-08-01

The Congo deep-sea fan is directly connected to the Congo River by a unique submarine canyon. The Congo River delivers up to 2×1012gPOC/yr, a part of which is funnelled by the submarine canyon and feeds the deep-sea environments. The more distal part of the Congo deep-sea fan, the terminal lobe area, has a surface of 2500 km2 and is situated up to 800 km offshore at depths of 4750-5000 m. It is a remarkable place to study the fate and distribution of the organic matter transferred from the continent to the deep ocean via turbidity currents. Forty-two samples were analyzed from the terminal lobes, including sites from the active channel, one of its levees and an abandoned distal channel. Samples were collected using multitube cores and push-cores using a Victor 6000 ROV, which surveyed the dense chemosynthetic habitats that locally characterize the terminal lobes. Palynofacies reveal a remarkably well-preserved, dominantly terrestrial particulate organic matter assemblage, that has been transferred from the continent into the deep-sea by turbidity currents. Delicate plant structures, cuticle fragments and plant cellular material is often preserved, highlighting the efficiency of turbidity currents to transfer terrestrial organic matter to the sea-floor, where it is preserved. Moreover, the palynofacies data reveal a general sorting by density or buoyancy of the organic particles, as the turbulent currents escaped the active channel, feeding the levees and the more distal, abandoned channel area. Finally, in addition to aforementioned hydrodynamic factors controlling the organic matter accumulation, a secondary influence of chemosynthetic habitats on organic matter preservation is also apparent. Palynofacies is therefore a useful tool to record the distribution of organic matter in recent and ancient deep-sea fan environments, an important topic for both academic and petroleum studies.

Probing velocity dependent self-interacting dark matter with neutrino telescopes

Science.gov (United States)

Robertson, Denis S.; Albuquerque, Ivone F. M.

2018-02-01

Self-interacting dark matter models constitute an attractive solution to problems in structure formation on small scales. A simple realization of these models considers the dark force mediated by a light particle which can couple to the Standard Model through mixings with the photon or the Z boson. Within this scenario we investigate the sensitivity of the IceCube-DeepCore and PINGU neutrino telescopes to the associated muon neutrino flux produced by dark matter annihilations in the Sun. Despite the model's simplicity, several effects naturally appear: momentum suppressed capture by nuclei, velocity dependent dark matter self-capture, Sommerfeld enhanced annihilation, as well as the enhancement on the neutrino flux due to mediator late decays. Taking all these effects into account, we find that most of the model relevant parameter space can be tested by the three years of data already collected by the IceCube-DeepCore. We show that indirect detection through neutrinos can compete with the strong existing limits from direct detection experiments, specially in the case of isospin violation.

Survival of marine heterotrophic flagellates isolated from the surface and the deep sea at high hydrostatic pressure: Literature review and own experiments

Science.gov (United States)

Živaljić, Suzana; Schoenle, Alexandra; Nitsche, Frank; Hohlfeld, Manon; Piechocki, Julia; Reif, Farina; Shumo, Marwa; Weiss, Alexandra; Werner, Jennifer; Witt, Madeleine; Voss, Janine; Arndt, Hartmut

2018-02-01

Although the abyssal seafloor represents the most common benthic environment on Earth, eukaryotic microbial life at abyssal depths is still an uncharted territory. This is in striking contrast to their potential importance regarding the material flux and bacteria consumption in the deep sea. Flagellate genotypes determined from sedimentary DNA deep-sea samples might originate from vital deep-sea populations or from cysts of organisms sedimented down from surface waters. The latter one may have never been active under deep-sea conditions. We wanted to analyze the principal ability of cultivable heterotrophic flagellates of different phylogenetic groups (choanoflagellates, ancyromonads, euglenids, kinetoplastids, bicosoecids, chrysomonads, and cercozoans) to survive exposure to high hydrostatic pressure (up to 670 bar). We summarized our own studies and the few available data from literature on pressure tolerances of flagellates isolated from different marine habitats. Our results demonstrated that many different flagellate species isolated from the surface waters and deep-sea sediments survived drastic changes in hydrostatic pressure. Barophilic behavior was also recorded for several species isolated from the deep sea indicating their possible genetic adaptation to high pressures. This is in accordance with records of heterotrophic flagellates present in environmental DNA surveys based on clone libraries established for deep-sea environments.

Iron oxide reduction in methane-rich deep Baltic Sea sediments

DEFF Research Database (Denmark)

Egger, Matthias; Hagens, Mathilde; Sapart, Celia J.

2017-01-01

/L transition. Our results reveal a complex interplay between production, oxidation and transport of methane showing that besides organoclastic Fe reduction, oxidation of downward migrating methane with Fe oxides may also explain the elevated concentrations of dissolved ferrous Fe in deep Baltic Sea sediments...... profiles and numerical modeling, we propose that a potential coupling between Fe oxide reduction and methane oxidation likely affects deep Fe cycling and related biogeochemical processes, such as burial of phosphorus, in systems subject to changes in organic matter loading or bottom water salinity....

Boldness in a deep sea hermit crab to simulated tactile predator attacks is unaffected by ocean acidification

Science.gov (United States)

Kim, Tae Won; Barry, James P.

2016-09-01

Despite rapidly growing interest in the effects of ocean acidification on marine animals, the ability of deep-sea animals to acclimate or adapt to reduced pH conditions has received little attention. Deep-sea species are generally thought to be less tolerant of environmental variation than shallow-living species because they inhabit relatively stable conditions for nearly all environmental parameters. To explore whether deep-sea hermit crabs ( Pagurus tanneri) can acclimate to ocean acidification over several weeks, we compared behavioral "boldness," measured as time taken to re-emerge from shells after a simulated predatory attack by a toy octopus, under ambient (pH ˜7.6) and expected future (pH ˜7.1) conditions. The boldness measure for crab behavioral responses did not differ between different pH treatments, suggesting that future deep-sea acidification would not influence anti-predatory behavior. However, we did not examine the effects of olfactory cues released by predators that may affect hermit crab behavior and could be influenced by changes in the ocean carbonate system driven by increasing CO2 levels.

Non-standard neutrino interactions in the mu–tau sector

Directory of Open Access Journals (Sweden)

Irina Mocioiu

2015-04-01

Full Text Available We discuss neutrino mass hierarchy implications arising from the effects of non-standard neutrino interactions on muon rates in high statistics atmospheric neutrino oscillation experiments like IceCube DeepCore. We concentrate on the mu–tau sector, which is presently the least constrained. It is shown that the magnitude of the effects depends strongly on the sign of the ϵμτ parameter describing this non-standard interaction. A simple analytic model is used to understand the parameter space where differences between the two signs are maximized. We discuss how this effect is partially degenerate with changing the neutrino mass hierarchy, as well as how this degeneracy could be lifted.

Ceramic Spheres—A Novel Solution to Deep Sea Buoyancy Modules

Science.gov (United States)

Jiang, Bo; Blugan, Gurdial; Sturzenegger, Philip N.; Gonzenbach, Urs T.; Misson, Michael; Thornberry, John; Stenerud, Runar; Cartlidge, David; Kuebler, Jakob

2016-01-01

Ceramic-based hollow spheres are considered a great driving force for many applications such as offshore buoyancy modules due to their large diameter to wall thickness ratio and uniform wall thickness geometric features. We have developed such thin-walled hollow spheres made of alumina using slip casting and sintering processes. A diameter as large as 50 mm with a wall thickness of 0.5–1.0 mm has been successfully achieved in these spheres. Their material and structural properties were examined by a series of characterization tools. Particularly, the feasibility of these spheres was investigated with respect to its application for deep sea (>3000 m) buoyancy modules. These spheres, sintered at 1600 °C and with 1.0 mm of wall thickness, have achieved buoyancy of more than 54%. As the sphere’s wall thickness was reduced (e.g., 0.5 mm), their buoyancy reached 72%. The mechanical performance of such spheres has shown a hydrostatic failure pressure above 150 MPa, corresponding to a rating depth below sea level of 5000 m considering a safety factor of 3. The developed alumina-based ceramic spheres are feasible for low cost and scaled-up production and show great potential at depths greater than those achievable by the current deep-sea buoyancy module technologies. PMID:28773651

Vertical migrations of a deep-sea fish and its prey.

Directory of Open Access Journals (Sweden)

Pedro Afonso

Full Text Available It has been speculated that some deep-sea fishes can display large vertical migrations and likely doing so to explore the full suite of benthopelagic food resources, especially the pelagic organisms of the deep scattering layer (DSL. This would help explain the success of fishes residing at seamounts and the increased biodiversity found in these features of the open ocean. We combined active plus passive acoustic telemetry of blackspot seabream with in situ environmental and biological (backscattering data collection at a seamount to verify if its behaviour is dominated by vertical movements as a response to temporal changes in environmental conditions and pelagic prey availability. We found that seabream extensively migrate up and down the water column, that these patterns are cyclic both in short-term (tidal, diel as well as long-term (seasonal scales, and that they partially match the availability of potential DSL prey components. Furthermore, the emerging pattern points to a more complex spatial behaviour than previously anticipated, suggesting a seasonal switch in the diel behaviour mode (benthic vs. pelagic of seabream, which may reflect an adaptation to differences in prey availability. This study is the first to document the fine scale three-dimensional behaviour of a deep-sea fish residing at seamounts.

Sedimentologic and volcanologic investigation of the deep tyrrhenian sea: preliminary result of cruise VST02

Directory of Open Access Journals (Sweden)

A. Bertagnini

2006-06-01

Full Text Available The VST02 cruise carried out in the summer of 2002 was focused at sedimentologic and volcanologic researches over selected areas of the deep portion of the Tyrrhenian sea. Chirp lines and seafloor samples were collected from the Calabrian slope surrounding Stromboli island, in the Marsili deep sea fan, in the Vavilov basin and in the Vavilov seamount. Submarine volcanic activity, both explosive and effusive, is occuring in the Stromboli edifice. Explosive submarine volcanism affects also the shallowest areas of the Vavilov seamount. Submarine carbonate lithification has been observed on the sediment-starved flanks of the Vavilov seamount. Acoustic transparent layers make up the recentmost infill of the Gortani basin, the easternmost portion of the Vavilov basin. Channels comprised of a variety of architectural elements and depositional lobes are the main elements of the Marsili deep-sea fan where, apparently, sedimentation occurs mainly through debris flow processes.

A precision measurement of sin2θw in neutrino nucleon scattering

International Nuclear Information System (INIS)

King, B.J.; Arroyo, C.G.; Bachmann, K.T.; Bazarko, A.O.; Bolton, T.; Foudas, C.; Lefmann, W.C.; Leung, W.C.; Mishra, S.R.; Oltman, E.; Quintas, P.Z.; Rabinowitz, S.A.; Sciulli, F.J.; Seligman, W.G.; Shaevitz, M.H.; Merritt, F.S.; Oreglia, M.J.; Schumm, B.A.; Bernstein, R.H.; Borcherding, F.; Fisk, H.E.; Lamm, M.J.; Marsh, W.; Merritt, K.W.B.; Schellman, H.M.; Yovanovitch, D.D.; Bodek, A.; Budd, H.S.; Barbaro, P. de; Sakumoto, W.K.; Kinnel, T.; Sandler, P.H.; Smith, W.H.

1993-01-01

A precise measurement of the weak mixing angle is reported from the ratio of the neutral current to charged current inclusive cross-sections in deep-inelastic neutrino-nucleon scattering. Using the on-shell definition, the value obtained is currently the most accurate determination of sin 2 θ w in a single experiment. The data were gathered at the CCFR neutrino detector in the Fermilab quadrupole-triplet wide-band neutrino beam, with neutrino energies up to 600 GeV. 2 figs., 1 tab., 14 refs

Proliferation and demise of deep-sea corals in the Mediterranean during the Younger Dryas

International Nuclear Information System (INIS)

McCulloch, Malcolm; Taviani, Marco; Lopez Correa, Matthias; Remia, Alessandro; Montagna, Paolo; Mortimer, Graham

2010-01-01

Uranium-series and radiocarbon ages are reported for deep-sea corals Madrepora oculata, Desmophyllum dianthus, Lophelia pertusa and Caryophyllia smithii from the Mediterranean Sea. U-series dating indicates that deep-sea corals have persisted in the Mediterranean for over 480, 000 years, especially during cool inter-stadial periods. The most prolific period of growth however appears to have occurred within the Younger Dryas (YD) period from 12, 900 to 11, 700 years BP followed by a short (∼ 330 years) phase of post-YD coral growth from 11, 230 to 10, 900 years BP. This indicates that deep-sea corals were prolific in the Mediterranean not only during the return to the more glacial-like conditions of the YD, but also following the rapid deglaciation and transition to warmer conditions that followed the end of the YD. Surprisingly, there is a paucity Last Glacial Maximum (LGM) coral ages, implying they were largely absent during this period when cold-water conditions were more prevalent. Radiocarbon ages show that the intermediate depth waters of the Mediterranean generally had Δ 14 C compositions similar to surface waters, indicating that these waters were extremely well ventilated. The only exception is a narrow period in the YD (12, 500 ± 100 years BP) when several samples of Lophelia pertusa from the Ionian Sea had Δ 14 C values falling significantly below the marine curve. Using a refined approach, isolation ages (T isol ) of 300 years to 500 years are estimated for these intermediate (800-1000 m) depth waters relative to surface marine waters, indicating a reduction or absence of deep-water formation in the Ionian and adjacent Adriatic Seas during the YD. Contrary to previous findings, we find no evidence for widespread intrusion of low Δ 14 C Atlantic waters into the Mediterranean. Prolific growth of deep-sea corals in the Mediterranean ended abruptly at ∼ 10, 900 years BP, with many of the coral-bearing mounds on the continental slopes being draped in

Proliferation and demise of deep-sea corals in the Mediterranean during the Younger Dryas

Energy Technology Data Exchange (ETDEWEB)

McCulloch, Malcolm [ARC Centre of Excellence for Coral Reef Studies, School of Earth and Environment, The University of Western Australian, Crawley, 6009, Western Australia (Australia); Research School of Earth Sciences, Australian National University, Canberra, 0200 (Australia); Taviani, Marco; Lopez Correa, Matthias; Remia, Alessandro [ISMAR-CNR, via Gobetti 101, I-40129 Bologna (Italy); Montagna, Paolo [LSCE, Av. de la Terrasse, 91198 Gif-sur-Yvette, France, ISMAR-CNR, via Gobetti 101, I-40129 Bologna (Italy); Mortimer, Graham [Research School of Earth Sciences, Australian National University, Canberra, 0200 (Australia)

2010-07-01

Uranium-series and radiocarbon ages are reported for deep-sea corals Madrepora oculata, Desmophyllum dianthus, Lophelia pertusa and Caryophyllia smithii from the Mediterranean Sea. U-series dating indicates that deep-sea corals have persisted in the Mediterranean for over 480, 000 years, especially during cool inter-stadial periods. The most prolific period of growth however appears to have occurred within the Younger Dryas (YD) period from 12, 900 to 11, 700 years BP followed by a short ({approx} 330 years) phase of post-YD coral growth from 11, 230 to 10, 900 years BP. This indicates that deep-sea corals were prolific in the Mediterranean not only during the return to the more glacial-like conditions of the YD, but also following the rapid deglaciation and transition to warmer conditions that followed the end of the YD. Surprisingly, there is a paucity Last Glacial Maximum (LGM) coral ages, implying they were largely absent during this period when cold-water conditions were more prevalent. Radiocarbon ages show that the intermediate depth waters of the Mediterranean generally had {Delta}{sup 14}C compositions similar to surface waters, indicating that these waters were extremely well ventilated. The only exception is a narrow period in the YD (12, 500 {+-} 100 years BP) when several samples of Lophelia pertusa from the Ionian Sea had {Delta}{sup 14}C values falling significantly below the marine curve. Using a refined approach, isolation ages (T{sub isol}) of 300 years to 500 years are estimated for these intermediate (800-1000 m) depth waters relative to surface marine waters, indicating a reduction or absence of deep-water formation in the Ionian and adjacent Adriatic Seas during the YD. Contrary to previous findings, we find no evidence for widespread intrusion of low {Delta}{sup 14}C Atlantic waters into the Mediterranean. Prolific growth of deep-sea corals in the Mediterranean ended abruptly at {approx} 10, 900 years BP, with many of the coral-bearing mounds

Fungal diversity in deep-sea sediments associated with asphalt seeps at the Sao Paulo Plateau

Science.gov (United States)

Nagano, Yuriko; Miura, Toshiko; Nishi, Shinro; Lima, Andre O.; Nakayama, Cristina; Pellizari, Vivian H.; Fujikura, Katsunori

2017-12-01

We investigated the fungal diversity in a total of 20 deep-sea sediment samples (of which 14 samples were associated with natural asphalt seeps and 6 samples were not associated) collected from two different sites at the Sao Paulo Plateau off Brazil by Ion Torrent PGM targeting ITS region of ribosomal RNA. Our results suggest that diverse fungi (113 operational taxonomic units (OTUs) based on clustering at 97% sequence similarity assigned into 9 classes and 31 genus) are present in deep-sea sediment samples collected at the Sao Paulo Plateau, dominated by Ascomycota (74.3%), followed by Basidiomycota (11.5%), unidentified fungi (7.1%), and sequences with no affiliation to any organisms in the public database (7.1%). However, it was revealed that only three species, namely Penicillium sp., Cadophora malorum and Rhodosporidium diobovatum, were dominant, with the majority of OTUs remaining a minor community. Unexpectedly, there was no significant difference in major fungal community structure between the asphalt seep and non-asphalt seep sites, despite the presence of mass hydrocarbon deposits and the high amount of macro organisms surrounding the asphalt seeps. However, there were some differences in the minor fungal communities, with possible asphalt degrading fungi present specifically in the asphalt seep sites. In contrast, some differences were found between the two different sampling sites. Classification of OTUs revealed that only 47 (41.6%) fungal OTUs exhibited >97% sequence similarity, in comparison with pre-existing ITS sequences in public databases, indicating that a majority of deep-sea inhabiting fungal taxa still remain undescribed. Although our knowledge on fungi and their role in deep-sea environments is still limited and scarce, this study increases our understanding of fungal diversity and community structure in deep-sea environments.

Far red bioluminescence from two deep-sea fishes.

Science.gov (United States)

Widder, E A; Latz, M I; Herring, P J; Case, J F

1984-08-03

Spectral measurements of red bioluminescence were obtained from the deep-sea stomiatoid fishes Aristostomias scintillans (Gilbert) and Malacosteus niger (Ayres). Red luminescence from suborbital light organs extends to the near infrared, with peak emission at approximately 705 nanometers in the far red. These fishes also have postorbital light organs that emit blue luminescence with maxima between 470 and 480 nanometers. The red bioluminescence may be due to an energy transfer system and wavelength-selective filtering.

A convolutional neural network neutrino event classifier

International Nuclear Information System (INIS)

Aurisano, A.; Sousa, A.; Radovic, A.; Vahle, P.; Rocco, D.; Pawloski, G.; Himmel, A.; Niner, E.; Messier, M.D.; Psihas, F.

2016-01-01

Convolutional neural networks (CNNs) have been widely applied in the computer vision community to solve complex problems in image recognition and analysis. We describe an application of the CNN technology to the problem of identifying particle interactions in sampling calorimeters used commonly in high energy physics and high energy neutrino physics in particular. Following a discussion of the core concepts of CNNs and recent innovations in CNN architectures related to the field of deep learning, we outline a specific application to the NOvA neutrino detector. This algorithm, CVN (Convolutional Visual Network) identifies neutrino interactions based on their topology without the need for detailed reconstruction and outperforms algorithms currently in use by the NOvA collaboration.

Long-term viability of carbon sequestration in deep-sea sediments

Science.gov (United States)

Teng, Y.; Zhang, D.

2017-12-01

Sequestration of carbon dioxide in deep-sea sediments has been proposed for the long-term storage of anthropogenic CO2, due to the negative buoyancy effect and hydrate formation under conditions of high pressure and low temperature. However, the multi-physics process of injection and post-injection fate of CO2 and the feasibility of sub-seabed disposal of CO2 under different geological and operational conditions have not been well studied. On the basis of a detailed study of the coupled processes, we investigate whether storing CO2 into deep-sea sediments is viable, efficient, and secure over the long term. Also studied are the evolution of the multiphase and multicomponent flow and the impact of hydrate formation on storage efficiency during the upward migration of the injected CO2. It is shown that low buoyancy and high viscosity slow down the ascending plume and the forming of the hydrate cap effectively reduces the permeability and finally becomes an impermeable seal, thus limiting the movement of CO2 towards the seafloor. Different flow patterns at varied time scales are identified through analyzing the mass distribution of CO2 in different phases over time. Observed is the formation of a fluid inclusion, which mainly consists of liquid CO2 and is encapsulated by an impermeable hydrate film in the diffusion-dominated stage. The trapped liquid CO2 and CO2 hydrate finally dissolve into the pore water through diffusion of the CO2 component. Sensitivity analyses are performed on storage efficiency under variable geological and operational conditions. It is found that under a deep-sea setting, CO2 sequestration in intact marine sediments is generally safe and permanent.

Muon Neutrino Disappearance in NOvA with a Deep Convolutional Neural Network Classifier

Energy Technology Data Exchange (ETDEWEB)

Rocco, Dominick Rosario [Minnesota U.

2016-03-01

The NuMI Off-axis Neutrino Appearance Experiment (NOvA) is designed to study neutrino oscillation in the NuMI (Neutrinos at the Main Injector) beam. NOvA observes neutrino oscillation using two detectors separated by a baseline of 810 km; a 14 kt Far Detector in Ash River, MN and a functionally identical 0.3 kt Near Detector at Fermilab. The experiment aims to provide new measurements of Δm² and θ23 and has potential to determine the neutrino mass hierarchy as well as observe CP violation in the neutrino sector. Essential to these analyses is the classification of neutrino interaction events in NOvA detectors. Raw detector output from NOvA is interpretable as a pair of images which provide orthogonal views of particle interactions. A recent advance in the field of computer vision is the advent of convolutional neural networks, which have delivered top results in the latest image recognition contests. This work presents an approach novel to particle physics analysis in which a convolutional neural network is used for classification of particle interactions. The approach has been demonstrated to improve the signal efficiency and purity of the event selection, and thus physics sensitivity. Early NOvA data has been analyzed (2.74×10²⁰ POT, 14 kt equivalent) to provide new best- fit measurements of sin²(θ23) = 0.43 (with a statistically-degenerate compliment near 0.60) and |Δm2 | = 2.48 × 10^-3 eV².

Clay as indicator of sediment plume movement in deep-sea environment

Digital Repository Service at National Institute of Oceanography (India)

Valsangkar, A.B.

artificially disturbed and resuspended 5 m above the seabed in 1997 during the Indian Deep-Sea Experiment. Initial studies have shown that the clay content during monitoring-1 phase significantly increased compared to post-disturbance, by 15 and 24...

Scientific Encounters of the Mysterious Sea. Reading Activities That Explore the Mysterious Creatures of the Deep Blue Sea. Grades 4-7.

Science.gov (United States)

Embry, Lynn

This activity book presents reading activities for grades 4-7 exploring the mysterious creatures of the deep sea. The creatures include: angel sharks; argonauts; barberfish; comb jelly; croakers; electric rays; flying fish; giganturid; lantern fish; narwhals; northern basket starfish; ocean sunfish; Portuguese man-of-war; sea cucumbers; sea…

Reconciling the sea level record of the last deglaciation with the δ18O spectra from deep sea cores

International Nuclear Information System (INIS)

Bard, Edouard; Columbia Univ., Palisades, NY; Arnold, Maurice; Duplessy, J.-C.

1991-01-01

In this paper we use the oxygen isotope record as a transient tracer to study palaeoceanography during the last deglaciation. By using 14 C and 18 O data obtained on four deep sea sediment cores, we show the presence of a measurable lag between the deglacial δ 18 O signal observed in the deep Atlantic and the deep Indo-Pacific oceans. Our study confirms that the major meltwater discharge occurred via the North Atlantic and that the thermohaline circulation was operating during the deglacial transition. (Author)

Measurement of the atmospheric muon neutrino energy spectrum with IceCube in the 79- and 86-String configuration

Directory of Open Access Journals (Sweden)

Ruhe T.

2016-01-01

Full Text Available IceCube is a neutrino telescope with an instrumented volume of one cubic kilometer. A total of 5160 Digital Optical Modules (DOMs is deployed on 86 strings forming a three dimensional detector array. Although primarily designed for the detection of neutrinos from astrophysical sources, the detector can be used for spectral measurements of atmospheric neutrinos. These spectral measurements are hindered by a dominant background of atmospheric muons. State-of-the-art techniques from Machine Learning and Data Mining are required to select a high-purity sample of atmospheric neutrino candidates. The energy spectrum of muon neutrinos is obtained from energy-dependent input variables by utilizing regularized unfolding. The results obtained using IceCube in the 79- and 86-string configuration are presented in this paper.

Future perspectives in neutrino physics: The Laguna-LBNO case

CERN Document Server

Buizza Avanzini, M

2013-01-01

LAGUNA-LBNO is a Design Study funded by the European Commission to develop the de- sign of a deep underground neutrino observatory; its physics program involves the study of neutrino oscillations at long baselines, the investigation of the Grand Unication of elemen- tary forces and the detection of neutrinos from known and unknown astrophysical sources. Building on the successful format and on the ndings of the previous LAGUNA Design Study, LAGUNA-LBNO is more focused and is specically considering Long Baseline Neutrino Oscil- lations (LBNO) with neutrino beams from CERN. Two sites, Frejus (in France at 130 km) and Pyhasalmi (in Finland at 2300 km), are being considered. Three dierent detector technolo- gies are being studied: Water Cherenkov, Liquid Scintillator and Liquid Argon. Recently the LAGUNA-LBNO consortium has submitted an Expression of Interest for a very long baseline neutrino experiment, selecting as a rst priority the option of a Liquid Argon detector at Pyhasalmi.

Neutrino astrophysics: a new tool for exploring the universe.

Science.gov (United States)

Waxman, Eli

2007-01-05

In the past four decades a new type of astronomy has emerged, where instead of looking up into the sky, "telescopes" are buried miles underground or deep under water or ice and search not for photons (that is, light), but rather for particles called neutrinos. Neutrinos are nearly massless particles that interact very weakly with matter. The detection of neutrinos emitted by the Sun and by a nearby supernova provided direct tests of the theory of stellar evolution and led to modifications of the standard model describing the properties of elementary particles. At present, several very large neutrino detectors are being constructed, aiming at the detection of the most powerful sources of energy and particles in the universe. The hope is that the detection of neutrinos from these sources, which are extra-Galactic and are most likely powered by mass accretion onto black holes, will not only allow study of the sources, but, much like solar neutrinos, will also provide new information about fundamental properties of matter.

Finite-size effects on multibody neutrino exchange

CERN Document Server

Abada, A; Rodríguez-Quintero, J; Abada, As

1998-01-01

The effect of multibody massless neutrino exchanges between neutrons inside a finite-size neutron star is studied. We use an effective Lagrangian, which incorporates the effect of the neutrons on the neutrinos. Following Schwinger, it is shown that the total interaction energy density is computed by comparing the zero point energy of the neutrino sea with and without the star. It has already been shown that in an infinite-size star the total energy due to neutrino exchange vanishes exactly. The opposite claim that massless neutrino exchange would produce a huge energy is due to an improper summation of an infrared-divergent quantity. The same vanishing of the total energy has been proved exactly in the case of a finite star in a one-dimensional toy model. Here we study the three-dimensional case. We first consider the effect of a sharp star border, assumed to be a plane. We find that there is a non- vanishing of the zero point energy density difference between the inside and the outside due to the refraction ...

The positioning system of the ANTARES Neutrino Telescope

Science.gov (United States)

Adrián-Martínez, S.; Ageron, M.; Aguilar, J. A.; Samarai, I. Al; Albert, A.; André, M.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Assis Jesus, A. C.; Astraatmadja, T.; Aubert, J.-J.; Baret, B.; Basa, S.; Bertin, V.; Biagi, S.; Bigi, A.; Bigongiari, C.; Bogazzi, C.; Bou-Cabo, M.; Bouhou, B.; Bouwhuis, M. C.; Brunner, J.; Busto, J.; Camarena, F.; Capone, A.; Cârloganu, C.; Carminati, G.; Carr, J.; Cecchini, S.; Charif, Z.; Charvis, Ph; Chiarusi, T.; Circella, M.; Coniglione, R.; Costantini, H.; Coyle, P.; Curtil, C.; De Bonis, G.; Decowski, M. P.; Dekeyser, I.; Deschamps, A.; Distefano, C.; Donzaud, C.; Dornic, D.; Dorosti, Q.; Drouhin, D.; Eberl, T.; Emanuele, U.; Enzenhöfer, A.; Ernenwein, J.-P.; Escoffier, S.; Fermani, P.; Ferri, M.; Flaminio, V.; Folger, F.; Fritsch, U.; Fuda, J.-L.; Galatà, S.; Gay, P.; Giacomelli, G.; Giordano, V.; Gómez-González, J. P.; Graf, K.; Guillard, G.; Halladjian, G.; Hallewell, G.; van Haren, H.; Hartman, J.; Heijboer, A. J.; Hello, Y.; Hernández-Rey, J. J.; Herold, B.; Hößl, J.; Hsu, C. C.; de Jong, M.; Kadler, M.; Kalekin, O.; Kappes, A.; Katz, U.; Kavatsyuk, O.; Keller, P.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kreykenbohm, I.; Kulikovskiy, V.; Lahmann, R.; Lamare, P.; Larosa, G.; Lattuada, D.; Lefèvre, D.; Le Van Suu, A.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Mangano, S.; Marcelin, M.; Margiotta, A.; Martínez-Mora, J. A.; Meli, A.; Montaruli, T.; Moscoso, L.; Motz, H.; Neff, M.; Nezri, E.; Niess, V.; Palioselitis, D.; Păvălaş, G. E.; Payet, K.; Payre, P.; Petrovic, J.; Piattelli, P.; Picot-Clemente, N.; Popa, V.; Pradier, T.; Presani, E.; Racca, C.; Real, D.; Reed, C.; Riccobene, G.; Richardt, C.; Richter, R.; Rivière, C.; Robert, A.; Roensch, K.; Rostovtsev, A.; Ruiz-Rivas, J.; Rujoiu, M.; Russo, G. V.; Salesa, F.; Samtleben, D. F. E.; Schöck, F.; Schuller, J.-P.; Schüssler, F.; Seitz, T.; Shanidze, R.; Simeone, F.; Spies, A.; Spurio, M.; Steijger, J. J. M.; Stolarczyk, Th; Sánchez-Losa, A.; Taiuti, M.; Tamburini, C.; Toscano, S.; Vallage, B.; Van Elewyck, V.; Vannoni, G.; Vecchi, M.; Vernin, P.; Wagner, S.; Wijnker, G.; Wilms, J.; de Wolf, E.; Yepes, H.; Zaborov, D.; Zornoza, J. D.; Zúñiga, J.

2012-08-01

The ANTARES neutrino telescope, located 40 km off the coast of Toulon in the Mediterranean Sea at a mooring depth of about 2475 m, consists of twelve detection lines equipped typically with 25 storeys. Every storey carries three optical modules that detect Cherenkov light induced by charged secondary particles (typically muons) coming from neutrino interactions. As these lines are flexible structures fixed to the sea bed and held taut by a buoy, sea currents cause the lines to move and the storeys to rotate. The knowledge of the position of the optical modules with a precision better than 10 cm is essential for a good reconstruction of particle tracks. In this paper the ANTARES positioning system is described. It consists of an acoustic positioning system, for distance triangulation, and a compass-tiltmeter system, for the measurement of the orientation and inclination of the storeys. Necessary corrections are discussed and the results of the detector alignment procedure are described.

The positioning system of the ANTARES Neutrino Telescope

International Nuclear Information System (INIS)

Adrián-Martínez, S; Ardid, M; Ageron, M; Samarai, I Al; Aubert, J-J; Bertin, V; Aguilar, J A; Albert, A; André, M; Anghinolfi, M; Anton, G; Anvar, S; Jesus, A C Assis; Astraatmadja, T; Baret, B; Basa, S; Biagi, S

2012-01-01

The ANTARES neutrino telescope, located 40 km off the coast of Toulon in the Mediterranean Sea at a mooring depth of about 2475 m, consists of twelve detection lines equipped typically with 25 storeys. Every storey carries three optical modules that detect Cherenkov light induced by charged secondary particles (typically muons) coming from neutrino interactions. As these lines are flexible structures fixed to the sea bed and held taut by a buoy, sea currents cause the lines to move and the storeys to rotate. The knowledge of the position of the optical modules with a precision better than 10 cm is essential for a good reconstruction of particle tracks. In this paper the ANTARES positioning system is described. It consists of an acoustic positioning system, for distance triangulation, and a compass-tiltmeter system, for the measurement of the orientation and inclination of the storeys. Necessary corrections are discussed and the results of the detector alignment procedure are described.

Standard physics solution to the solar neutrino problem?

Energy Technology Data Exchange (ETDEWEB)

Dar, A [Technion-Israel Inst. of Tech., Haifa (Israel). Dept. of Physics

1996-11-01

The {sup 8}B solar neutrino flux predicted by the standard solar model (SSM) is consistent within the theoretical and experimental uncertainties with that at Kamiokande. The Gallium and Chlorine solar neutrino experiments, however, seem to imply that the {sup 7}Be solar neutrino flux is strongly suppressed compared with that predicted by the SSM. If the {sup 7}Be solar neutrino flux is suppressed, still it can be due to astrophysical effects not included in the simplistic SSM. Such effects include short term fluctuations or periodic variation of the temperature in the solar core, rotational mixing of {sup 3}He in the solar core, and dense plasma effects which may strongly enhance p-capture by {sup 7}Be relative to e-capture. The new generation of solar observations which already look non stop deep into the sun, like Superkamiokande through neutrinos, and SOHO and GONG through acoustic waves, may point at the correct solution. Only Superkamiokande and/or future solar neutrino experiments, such as SNO, BOREXINO and HELLAZ, will be able to find out whether the solar neutrino problem is caused by neutrino properties beyond the minimal standard electroweak model or whether it is just a problem of the too simplistic standard solar model. (author) 1 fig., 3 tabs., refs.

UNDERGROUND

Energy Technology Data Exchange (ETDEWEB)

Anon.

1993-11-15

Full text: Cossetted deep underground, sheltered from cosmic ray noise, has always been a favourite haunt of neutrino physicists. Already in the 1930s, significant limits were obtained by taking a geiger counter down in Holborn 'tube' station, one of the deepest in London's underground system. Since then, neutrino physicists have popped up in many unlikely places - gold mines, salt mines, and road tunnels deep under mountain chains. Two such locations - the 1MB (Irvine/ Michigan/Brookhaven) detector 600 metres below ground in an Ohio salt mine, and the Kamiokande apparatus 1000m underground 300 km west of Tokyo - picked up neutrinos on 23 February 1987 from the famous 1987A supernova. Purpose-built underground laboratories have made life easier, notably the Italian Gran Sasso Laboratory near Rome, 1.4 kilometres below the surface, and the Russian Baksan Neutrino Observatory under Mount Andyrchi in the Caucasus range. Gran Sasso houses ICARUS (April, page 15), Gallex, Borexino, Macro and the LVD Large Volume Detector, while Baksan is the home of the SAGE gallium-based solar neutrino experiment. Elsewhere, important ongoing underground neutrino experiments include Soudan II in the US (April, page 16), the Canadian Sudbury Neutrino Observatory with its heavy water target (January 1990, page 23), and Superkamiokande in Japan (May 1991, page 8)