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Sample records for aequorea victoria jellyfish

  1. Control of swimming in the hydrozoan jellyfish Aequorea victoria: subumbrellar organization and local inhibition.

    PubMed

    Satterlie, Richard A

    2008-11-01

    The subumbrella of the hydrozoan jellyfish Aequorea victoria (previously classified as Aequorea aequorea) is divided by numerous radial canals and attached gonads, so the subumbrellar musculature is partitioned into subumbrellar segments. The ectoderm of each segment includes two types of muscle: smooth muscle with a radial orientation, used for local (feeding and righting) and widespread (protective) radial responses, and striated muscle with a circular orientation which produces swim contractions. Two subumbrellar nerve nets were found, one of which stained with a commercial antibody produced against the bioactive peptide FMRFamide. Circular muscle cells produce a single, long-duration action potential with each swim, triggered by a single junctional potential. In addition, the circular cells are electrically coupled so full contractions require both electrotonic depolarization from adjacent cells and synaptic input from a subumbrellar nerve net. The radial cells, which form a layer superficial to the circular cells, are also activated by a subumbrellar nerve net, and produce short-duration action potentials. The radial muscle cells are electrically coupled to one another. No coupling exists between the two muscle layers. Spread of excitation between adjacent segments is decremental, and nerve net-activated junctional potentials disappear during local inhibition of swimming (such as with a radial response). Variable swim contractions are controlled by a combination of synaptic input from the motor network of the inner nerve ring, synaptic input from a subumbrellar nerve net, and electrotonic depolarization from adjacent, active muscle cells.

  2. Aequorea victoria bioluminescence moves into an exciting new era.

    PubMed

    Kendall, J M; Badminton, M N

    1998-05-01

    Bioluminescence has revolutionized research into many cellular and molecular-biological processes, ranging from intracellular signalling to gene transcription. This article focuses on the chemistry and biotechnological exploitation of the two proteins involved in bioluminescence of the jellyfish Aequorea victoria--aequorin and green fluorescent protein. Engineered recombinant aequorin has led to a novel technological approach to monitoring calcium signals in organelles and subcellular domains. A new generation of intracellular calcium indicators has been produced in which engineered variants of green fluorescent protein are used to probe their ionic environment using intramolecular fluorescence-resonance-energy transfer.

  3. Crystal structure of the Aequorea victoria green fluorescent protein.

    PubMed

    Ormö, M; Cubitt, A B; Kallio, K; Gross, L A; Tsien, R Y; Remington, S J

    1996-09-06

    The green fluorescent protein (GFP) from the Pacific Northwest jellyfish Aequorea victoria has generated intense interest as a marker for gene expression and localization of gene products. The chromophore, resulting from the spontaneous cyclization and oxidation of the sequence -Ser65 (or Thr65)-Tyr66-Gly67-, requires the native protein fold for both formation and fluorescence emission. The structure of Thr65 GFP has been determined at 1.9 angstrom resolution. The protein fold consists of an 11-stranded beta barrel with a coaxial helix, with the chromophore forming from the central helix. Directed mutagenesis of one residue adjacent to the chromophore, Thr203, to Tyr or His results in significantly red-shifted excitation and emission maxima.

  4. Crystal Structure of the Aequorea victoria Green Fluorescent Protein

    NASA Astrophysics Data System (ADS)

    Ormo, Mats; Cubitt, Andrew B.; Kallio, Karen; Gross, Larry A.; Tsien, Roger Y.; Remington, S. James

    1996-09-01

    The green fluorescent protein (GFP) from the Pacific Northwest jellyfish Aequorea victoria has generated intense interest as a marker for gene expression and localization of gene products. The chromophore, resulting from the spontaneous cyclization and oxidation of the sequence -Ser65 (or Thr65)-Tyr66-Gly67-, requires the native protein fold for both formation and fluorescence emission. The structure of Thr65 GFP has been determined at 1.9 angstrom resolution. The protein fold consists of an 11-stranded β barrel with a coaxial helix, with the chromophore forming from the central helix. Directed mutagenesis of one residue adjacent to the chromophore, Thr203, to Tyr or His results in significantly red-shifted excitation and emission maxima.

  5. Sound scattering by the gelatinous zooplankters Aequorea victoria and Pleurobrachia bachei

    NASA Astrophysics Data System (ADS)

    Monger, B. C.; Chinniah-Chandy, S.; Meir, E.; Billings, S.; Greene, C. H.; Wiebe, P. H.

    Target strengths were determined for individual Aequorea victoria and Pleurobrachia bachei using separate 200, 420 and 1,000 kHz transducers in an enclosure deployed off the dock of the Friday Harbor Laboratories in northern Puget Sound, Washington, USA. The target strength for Aequorea, when averaged over all animal sizes and all three trnasducer frequencies, was -72.6 dB. The target strength for Pleurobrachia was -75.9 dB when similarly averaged. Average reduced target strengths for Aequorea and Pleurobrachia were -43.3 and -33.1 dB, respectively. Differences in the sound scattering contrasts for Pleurobrachia and Aequorea are proposed to explain the larger reduced target strength of Pleurobrachia, relative to that of Aequorea. A new sound scattering model was developed to predict the backscattering cross-section of Aequorea. The model takes into account expected variations in target strength due to changes in shape of the jellyfish as it propels itself through the water. The scattering model was tuned specifically for Aequorea in the present study, but has a general formulation that is widely applicable to any medusa-shaped gelatinous zooplankter.

  6. Bioluminescence of Aequorea macrodactyla, a common jellyfish species in the East China Sea.

    PubMed

    Xia, Ning-Shao; Luo, Wen-Xin; Zhang, Jun; Xie, Xiao-Yan; Yang, Hai-Jie; Li, Shao-Wei; Chen, Ming; Ng, Mun-Hon

    2002-03-01

    Studies of the bioluminescent mechanisms of jellyfish have been mainly confined to one species, Aequorea victoria. We describe the luminescent system of another species, Aequorea macrodactyla, which is commonly found in the warmer waters on the coastal region of East China Sea. The luminescent system of this species consists of a green fluorescent protein (GFP) and one or more aequorins. The GFP gene is 1042 bp. It encompasses a coding sequence of 717 bp organized as 3 exons, and it is predicted to specify a 27-kDa peptide, which shares 80% amino acid sequence identity with the GFP of A. victoria. The entire coding sequence was cloned into the pTO-T7 expression vector and expressed in Escherichia coli. Compared with GFP of A. victoria, the purified expressed protein exhibited an excitation peak at a higher wavelength of 476 nm and an emission peak at a lower wavelength of 496 nm, with a higher quantum yield of 1.0. The other photoprotein, aequorin, is encoded in a single open reading frame of 585 bp specifying a 23-kDa apoprotein. The gene was cloned in to the same expression vector and expressed in E. coli. The activity of the photoprotein was reconstituted by incubating the expressed apoprotein with coelenterazine f. In the presence of Ca(2+) the reconstituted aequorin exhibits an emission peak at 470 nm. The kinetics of regeneration and the photoactivities of the reconstituted aequorins of the 2 species of jellyfish are similar. Nevertheless, Aequorea macrodactyla is expected to appear brighter and more "blue" than Aequorea victorea because of the differences in the photoactivity of their GFPs.

  7. Preparation and initial characterization of crystals of the photoprotein aequorin from Aequorea victoria.

    PubMed

    Hannick, L I; Prasher, D C; Schultz, L W; Deschamps, J R; Ward, K B

    1993-01-01

    Crystals of recombinant aequorin, the photoprotein from the jellyfish Aequorea victoria, have been grown from solutions containing sodium phosphate. The crystals grow as thin plates which diffract to beyond 2.2 A resolution. The crystals are orthorhombic, space group P2(1)2(1)2(1); the axes are a = 89.1(1), b = 88.4(1), and c = 52.7(1) A. The asymmetric unit contains two molecules. Crystals exposed to calcium ion solutions emit a steady glow and slowly deteriorate, confirming that the crystals consist of a charged, competent photoprotein. This represents the first successful preparation of single crystals of a photoprotein suitable for diffraction analysis.

  8. Flow structures and fluid transport for the hydromedusae Sarsia tubulosa and Aequorea victoria.

    PubMed

    Lipinski, Doug; Mohseni, Kamran

    2009-08-01

    The flow structures produced by the hydromedusae Sarsia tubulosa and Aequorea victoria are examined using direct numerical simulation and Lagrangian coherent structures (LCS). Body motion of each hydromedusa is digitized and input to a CFD program. Sarsia tubulosa uses a jetting type of propulsion, emitting a single, strong, fast-moving vortex ring during each swimming cycle while a secondary vortex of opposite rotation remains trapped within the subumbrellar region. The ejected vortex is highly energetic and moves away from the hydromedusa very rapidly. Conversely, A. victoria, a paddling type hydromedusa, is found to draw fluid from the upper bell surface and eject this fluid in pairs of counter-rotating, slow-moving vortices near the bell margins. Unlike S. tubulosa, both vortices are ejected during the swimming cycle of A. victoria and linger in the tentacle region. In fact, we find that A. victoria and S. tubulosa swim with Strouhal numbers of 1.1 and 0.1, respectively. This means that vortices produced by A. victoria remain in the tentacle region roughly 10 times as long as those produced by S. tubulosa, which presents an excellent feeding opportunity during swimming for A. victoria. Finally, we examine the pressure on the interior bell surface of both hydromedusae and the velocity profile in the wake. We find that S. tubulosa produces very uniform pressure on the interior of the bell as well as a very uniform jet velocity across the velar opening. This type of swimming can be well approximated by a slug model, but A. victoria creates more complicated pressure and velocity profiles. We are also able to estimate the power output of S. tubulosa and find good agreement with other hydromedusan power outputs. All results are based on numerical simulations of the swimming jellyfish.

  9. Primary structure of the Aequorea victoria green-fluorescent protein.

    PubMed

    Prasher, D C; Eckenrode, V K; Ward, W W; Prendergast, F G; Cormier, M J

    1992-02-15

    Many cnidarians utilize green-fluorescent proteins (GFPs) as energy-transfer acceptors in bioluminescence. GFPs fluoresce in vivo upon receiving energy from either a luciferase-oxyluciferin excited-state complex or a Ca(2+)-activated phosphoprotein. These highly fluorescent proteins are unique due to the chemical nature of their chromophore, which is comprised of modified amino acid (aa) residues within the polypeptide. This report describes the cloning and sequencing of both cDNA and genomic clones of GFP from the cnidarian, Aequorea victoria. The gfp10 cDNA encodes a 238-aa-residue polypeptide with a calculated Mr of 26,888. Comparison of A. victoria GFP genomic clones shows three different restriction enzyme patterns which suggests that at least three different genes are present in the A. victoria population at Friday Harbor, Washington. The gfp gene encoded by the lambda GFP2 genomic clone is comprised of at least three exons spread over 2.6 kb. The nucleotide sequences of the cDNA and the gene will aid in the elucidation of structure-function relationships in this unique class of proteins.

  10. Development of a photoactivatable fluorescent protein from Aequorea victoria GFP

    NASA Astrophysics Data System (ADS)

    Patterson, George H.; Lippincott-Schwartz, Jennifer

    2004-06-01

    Photoactivation, the rapid conversion of photoactivatable molecules to a fluorescent state by intense irradiation, can be used to mark and monitor selected molecules within cells1. We report a photoactivatable variant of the Aequorea victoria green fluorescent protein (GFP) based on a mutation at position 203 that upon intense irradiation with 413 nm light exhibits a stable 60-100 fluorescence increase under 488 nm excitation. The photoactivated form of this mutant named photoactivatable GFP (PA-GFP), is stable under a number of conditions. PA-GFP can be used to analyze protein dynamics in living cells, offering enormous potential for addressing outstanding questions in protein trafficking and turnover, organelle dynamics, and cell lineage patterns.

  11. Deletion mapping of the Aequorea victoria green fluorescent protein.

    PubMed

    Dopf, J; Horiagon, T M

    1996-01-01

    Aequorea victoria green fluorescent protein (GFP) is a promising fluorescent marker which is active in a diverse array of prokaryotic and eukaryotic organisms. A key feature underlying the versatility of GFP is its capacity to undergo heterocyclic chromophore formation by cyclization of a tripeptide present in its primary sequence and thereby acquiring fluorescent activity in a variety of intracellular environments. In order to define further the primary structure requirements for chromophore formation and fluorescence in GFP, a series of N- and C-terminal GFP deletion variant expression vectors were created using the polymerase chain reaction. Scanning spectrofluorometric analyses of crude soluble protein extracts derived from eleven GFP expression constructs revealed that amino acid (aa) residues 2-232, of a total of 238 aa in the native protein, were required for the characteristic emission and absorption spectra of native GFP. Heterocyclic chromophore formation was assayed by comparing the absorption spectrum of GFP deletion variants over the 300-500-nm range to the absorption spectra of full-length GFP and GFP deletion variants missing the chromophore substrate domain from the primary sequence. GFP deletion variants lacking fluorescent activity showed no evidence of heterocyclic ring structure formation when the soluble extracts of their bacterial expression hosts were studied at pH 7.9. These observations suggest that the primary structure requirements for the fluorescent activity of GFP are relatively extensive and are compatible with the view that much of the primary structure serves an autocatalytic function.

  12. Detection of protein-protein interactions using Aequorea victoria bioluminescence resonance energy transfer

    NASA Astrophysics Data System (ADS)

    Vinokurov, Leonid M.; Gorokhovatsky, Andrey Y.; Rudenko, Natalia V.; Marchenkov, Victor V.; Skosyrev, Vitaly S.; Arzhanov, Maxim A.; Zakharov, Mikhail V.; Burkhardt, Nils; Semisotnov, Gennady V.; Alakhov, Yuli B.

    2003-07-01

    Bioluminescence resonance energy transfer (BRET) is a naturally occurring phenomenon taking place in some marine coelenterates. Emission of light in these organisms involves the energy transfer between chromophores of donor luciferase and acceptor fluorescent protein. Due to the strict dependence of BRET efficiency on the inter-chromophore distance, the phenomenon has been applied to study protein-protein interactions by fusing interacting partners with either donor or acceptor proteins. Here we describe a BRET-based homogeneous protein-protein interaction assay exploiting novel donor-acceptor pair formed by photoproteins of jellyfish Aequorea victoria bioluminescent system, aequorin and green fluorescent protein enhanced variant (EGFP). Two known interacting proteins, streptavidin (SAV) and biotin carboxyl carrier protein (BCCP) were fused, respectively, with aequorin and EGFP. The fusions were purified after expression of the corresponding genes in Escherichia coli cells. Association of SAV-Aequorin and BCCP-EGFP was followed by BRET between aequorin (donor) and EGFP (acceptor) resulting in significantly increasing 510 nm and decreasing 470 nm bioluminescence intensity. It was shown that free biotin inhibited BRET due to its competition with BCCP-EGFP for binding to SAV-Aequorin. These properties were exploited to demonstrate competitive homogeneous BRET assay for biotin.

  13. Luminescent proteins from Aequorea victoria: applications in drug discovery and in high throughput analysis.

    PubMed

    Deo, S K; Daunert, S

    2001-02-01

    Recent progress in generating a vast number of drug targets through genomics and large compound libraries through combinatorial chemistry have stimulated advancements in drug discovery through the development of new high throughput screening (HTS) methods. Automation and HTS techniques are also highly desired in fields such as clinical diagnostics. Luminescence-based assays have emerged as an alternative to radiolabel-based assays in HTS as they approach the sensitivity of radioactive detection along with ease of operation, which makes them amenable to miniaturization. Luminescent proteins provide the advantage of reduced reagent and operating costs because they can be produced in unlimited amounts through the use of genetic engineering tools. In that regard, the use of two naturally occurring and recombinantly produced luminescent proteins from the jellyfish Aequorea victoria, namely, aequorin and the green fluorescent protein (GFP), has attracted attention in a number of analytical applications in diverse research areas. Aequorin is naturally bioluminescent and has therefore, virtually no associated background signal, which allows its detection down to attomole levels. GFP has become the reporter of choice in a variety of applications given that it is an autofluorescent protein that does not require addition of any co-factors for fluorescence emission. Furthermore, the generation of various mutants of GFP with differing luminescent and spectral properties has spurred additional interest in this protein. In this review, we focus on the use of aequorin and GFP in the development of highly sensitive assays that find applications in drug discovery and in high throughput analysis.

  14. The first mutant of the Aequorea victoria green fluorescent protein that forms a red chromophore.

    PubMed

    Mishin, Alexander S; Subach, Fedor V; Yampolsky, Ilia V; King, William; Lukyanov, Konstantin A; Verkhusha, Vladislav V

    2008-04-22

    Green fluorescent protein (GFP) from a jellyfish, Aequorea victoria, and its mutants are widely used in biomedical studies as fluorescent markers. In spite of the enormous efforts of academia and industry toward generating its red fluorescent mutants, no GFP variants with emission maximum at more than 529 nm have been developed during the 15 years since its cloning. Here, we used a new strategy of molecular evolution aimed at generating a red-emitting mutant of GFP. As a result, we have succeeded in producing the first GFP mutant that substantially matures to the red-emitting state with excitation and emission maxima at 555 and 585 nm, respectively. A novel, nonoxidative mechanism for formation of the red chromophore in this mutant that includes a dehydration of the Ser65 side chain has been proposed. Model experiments showed that the novel dual-color GFP mutant with green and red emission is suitable for multicolor flow cytometry as an additional color since it is clearly separable from both green and red fluorescent tags.

  15. Functional expression of the Aequorea victoria green fluorescent protein in insect cells using the baculovirus expression system.

    PubMed

    Reiländer, H; Haase, W; Maul, G

    1996-02-06

    A DNA fragment encoding the green fluorescent protein (GFP) was isolated via PCR from a jellyfish Aequorea victoria cDNA, cloned and sequenced. Subsequently, a recombinant baculovirus bearing the coding region of the GFP under the transcriptional control of the Autographa californica nuclear polyhedrosis virus (AcMNPV) polyhedrin gene promoter was constructed and isolated. High-level expression of GFP could be easily monitored in Spodoptera frugiperda (Sf9) insect cells after infection with recombinant baculovirus, due to the intrinsic fluorescence (lambda(max) = 508 nm) of the recombinant protein after excitation with blue light (lambda(max) = 400 nm). The functional recombinant GFP displayed an apparent molecular mass of approximately 43 kDa and the fluorescence emission spectrum of the recombinant protein was virtually identical to that of the native green fluorescent protein.

  16. Detection of Aequorea victoria green fluorescent protein by capillary electrophoresis laser induced fluorescence detection.

    PubMed

    Craig, D B; Wong, J C; Dovichi, N J

    1997-01-01

    Aequorea victoria green fluorescent protein was assayed by capillary electrophoresis using post-capillary laser-induced fluorescence detection in a sheath flow cuvette. The limit of detection was 3.0 x 10(-12) M protein in an injection volume of 17 nL, corresponding to a mass of 3100 molecules.

  17. Deletions of the Aequorea victoria green fluorescent protein define the minimal domain required for fluorescence.

    PubMed

    Li, X; Zhang, G; Ngo, N; Zhao, X; Kain, S R; Huang, C C

    1997-11-07

    The Green Fluorescent Protein (GFP) from the jellyfish Aequorea victoria is a widely used marker for gene expression and protein localization studies. Dissection of the structure of the protein would be expected to shed light on its potential applications to other fields such as the detection of protease activity. Using deletion analysis, we have defined the minimal domain in GFP required for fluorescence to amino acids 7-229. This domain starts at the middle of the first small alpha helix at the N terminus of GFP and ends immediately following the last beta sheet. Studies of the amino acids at both termini of the minimal domain revealed that positions 6 and 7 at the N terminus are Glu-specific. Change of the Glu residues to other amino acids results in reduction of GFP fluorescence. Position 229 at the C terminus of GFP, however, is nonspecific: the Ile can be replaced with other amino acids with no measurable loss of fluorescence. A total of only 15 terminal amino acids can be deleted from GFP without disrupting fluorescence, consistent with findings of a previous study of GFP crystal structure (Ormo, M., Cubitt, A. B., Kallio, K., Gross, L. A., Tsien, R. Y., Remington, S. J. (1996) Science 273, 1392-1395 and Yang, F., Moss, L. G., and Phillips, G. N., Jr. (1996) Nat. Biotechnol. 14, 1246-1251) that a tightly packed structure exists in the protein. We also generated internal deletions within the loop regions of GFP according to its crystal structure and found that all such deletions eliminated GFP fluorescence.

  18. An arbitrary Lagrangian-Eulerian formulation for the numerical simulation of flow patterns generated by the hydromedusa Aequorea victoria

    NASA Astrophysics Data System (ADS)

    Sahin, Mehmet; Mohseni, Kamran

    2009-07-01

    A new geometrically conservative arbitrary Lagrangian-Eulerian (ALE) formulation is presented for the moving boundary problems in the swirl-free cylindrical coordinates. The governing equations are multiplied with the radial distance and integrated over arbitrary moving Lagrangian-Eulerian quadrilateral elements. Therefore, the continuity and the geometric conservation equations take very simple form similar to those of the Cartesian coordinates. The continuity equation is satisfied exactly within each element and a special attention is given to satisfy the geometric conservation law (GCL) at the discrete level. The equation of motion of a deforming body is solved in addition to the Navier-Stokes equations in a fully-coupled form. The mesh deformation is achieved by solving the linear elasticity equation at each time level while avoiding remeshing in order to enhance numerical robustness. The resulting algebraic linear systems are solved using an ILU(k) preconditioned GMRES method provided by the PETSc library. The present ALE method is validated for the steady and oscillatory flow around a sphere in a cylindrical tube and applied to the investigation of the flow patterns around a free-swimming hydromedusa Aequorea victoria (crystal jellyfish). The calculations for the hydromedusa indicate the shed of the opposite signed vortex rings very close to each other and the formation of large induced velocities along the line of interaction while the ring vortices moving away from the hydromedusa. In addition, the propulsion efficiency of the free-swimming hydromedusa is computed and its value is compared with values from the literature for several other species.

  19. Single amino acid replacement makes Aequorea victoria fluorescent proteins reversibly photoswitchable.

    PubMed

    Bizzarri, Ranieri; Serresi, Michela; Cardarelli, Francesco; Abbruzzetti, Stefania; Campanini, Barbara; Viappiani, Cristiano; Beltram, Fabio

    2010-01-13

    Reversibly photoswitchable (i.e., photochromic) fluorescent proteins open the way to a number of advanced bioimaging techniques applicable to living-cell studies such as sequential photolabeling of distinct cellular regions, innovative FRET schemes, or nanoscopy. Owing to the relevance of fluorescent proteins from Aequorea victoria (AFPs) for cell biology, a photochromic "toolbox" constituted by several AFPs is highly desirable. Here we introduce four new photochromic AFPs whose reversible photoswitching occurs between the native bright and a dark state at low illumination power, on account of a very efficient cis-trans photoisomerization. Most remarkably, the optical bistability of these AFPs derives from the single E222Q mutation in the primary sequence. Apparently, the E222Q substitution can restore the intrinsic photochromic behavior of the isolated chromophore. The significance of these mutants for high-resolution in vivo cell imaging is shown by means of photochromic FRET experiments.

  20. Fusion of Aequorea victoria GFP and aequorin provides their Ca(2+)-induced interaction that results in red shift of GFP absorption and efficient bioluminescence energy transfer.

    PubMed

    Gorokhovatsky, Andrey Yu; Marchenkov, Victor V; Rudenko, Natalia V; Ivashina, Tanya V; Ksenzenko, Vladimir N; Burkhardt, Nils; Semisotnov, Gennady V; Vinokurov, Leonid M; Alakhov, Yuli B

    2004-07-30

    The bioluminescence emitted by Aequorea victoria jellyfish is greenish while its single bioluminescent photoprotein aequorin emits blue light. This phenomenon may be explained by a bioluminescence resonance energy transfer (BRET) from aequorin chromophore to green fluorescent protein (GFP) co-localized with it. However, a slight overlapping of the aequorin bioluminescence spectrum with the GFP absorption spectrum and the absence of marked interaction between these proteins in vitro pose a question on the mechanism providing the efficient BRET in A. victoria. Here we report the in vitro study of BRET between homologous Ca(2+)-activated photoproteins, aequorin or obelin (Obelia longissima), as bioluminescence energy donors, and GFP, as an acceptor. The fusions containing donor and acceptor proteins linked by a 19 aa peptide were purified after expressing their genes in Escherichia coli cells. It was shown that the GFP-aequorin fusion has a significantly greater BRET efficiency, compared to the GFP-obelin fusion. Two main factors responsible for the difference in BRET efficiency of these fusions were revealed. First, it is the presence of Ca(2+)-induced interaction between the donor and acceptor in the aequorin-containing fusion and the absence of the interaction in the obelin-containing fusion. Second, it is a red shift of GFP absorption toward better overlapping with aequorin bioluminescence induced by the interaction of aequorin with GFP. Since the connection of the two proteins in vitro mimics their proximity in vivo, Ca(2+)-induced interaction between aequorin and GFP may occur in A. victoria jellyfish providing efficient BRET in this organism.

  1. Identifying and modeling motion primitives for the hydromedusae Sarsia tubulosa and Aequorea victoria.

    PubMed

    Sledge, Isaac; Krieg, Michael; Lipinski, Doug; Mohseni, Kamran

    2015-10-23

    The movements of organisms can be thought of as aggregations of motion primitives: motion segments containing one or more significant actions. Here, we present a means to identify and characterize motion primitives from recorded movement data. We address these problems by assuming that the motion sequences can be characterized as a series of dynamical-system-based pattern generators. By adopting a nonparametric, Bayesian formalism for learning and simplifying these pattern generators, we arrive at a purely data-driven model to automatically identify breakpoints in the movement sequences. We apply this model to swimming sequences from two hydromedusa. The first hydromedusa is the prolate Sarsia tubulosa, for which we obtain five motion primitives that correspond to bell cavity pressurization, jet formation, jetting, cavity fluid refill, and coasting. The second hydromedusa is the oblate Aequorea victoria, for which we obtain five motion primitives that correspond to bell compression, vortex separation, cavity fluid refill, vortex formation, and coasting. Our experimental results indicate that the breakpoints between primitives are correlated with transitions in the bell geometry, vortex formation and shedding, and changes in derived dynamical quantities. These dynamics quantities include terms like pressure, power, drag, and thrust. Such findings suggest that dynamics information is inherently present in the observed motions.

  2. Structural and spectral response of Aequorea victoria green fluorescent proteins to chromophore fluorination.

    PubMed

    Pal, Prajna P; Bae, Jae Hyun; Azim, M Kamran; Hess, Petra; Friedrich, Rainer; Huber, Robert; Moroder, Luis; Budisa, Nediljko

    2005-03-15

    Global replacements of tyrosine by 2- and 3-fluorotyrosine in "enhanced green" and "enhanced yellow" mutants of Aequorea victoria green fluorescent proteins (avGFPs) provided protein variants with novel biophysical properties. While crystallographic and modeled structures of these proteins are indistinguishable from those of their native counterparts (i.e., they are perfectly isomorphous), there are considerable differences in their spectroscopic properties. The fluorine being an integral part of the avGFP chromophore induces changes in the titration curves, variations in the intensity of the absorbance and fluorescence, and spectral shifts in the emission maxima. Furthermore, targeted fluorination in close proximity to the fluorinated chromophore yielded additional variants with considerably enhanced spectral changes. These unique spectral properties are intrinsic features of the fluorinated avGFPs, in the context of the rigid chromophore-microenvironment interactions. The availability of the isomorpohous crystal structures of fluorinated avGFPs allowed mapping of novel, unusual interaction distances created by the presence of fluorine atoms. In addition, fluorine atoms in the ortho position of the chromophore tyrosyl moiety exhibit a single conformation, while in the meta position two conformer states were observed in the crystalline state. Such global replacements in chromophores of avGFPs and similar proteins result in "atomic mutations" (i.e., H --> F replacements) in the structures, offering unprecedented opportunities to understand and manipulate the relationships between protein structure and spectroscopic properties.

  3. The Aequorea victoria green fluorescent protein can be used as a reporter in live zebrafish embryos.

    PubMed

    Amsterdam, A; Lin, S; Hopkins, N

    1995-09-01

    The green fluorescent protein (GFP) from the cnidarian Aequorea victoria is capable of producing fluorescence without an exogenously added substrate. Here we demonstrate that a cDNA for GFP driven by a Xenopus elongation factor 1 alpha enhancer-promoter can confer fluorescence upon live zebrafish embryos, either as an injected plasmid or as a transgene after passage through the germline. When injected into zebrafish embryos at the one-cell stage, this construct starts to express detectable GFP after about 4 hr of development at 28 degrees C, about 1 hr after the midblastula transition. Fluorescence can be observed in cells of many tissue types in the embryo for at least 3 weeks after injection. We used three different expression constructs, each employing a modified ef1 alpha enhancer-promoter, to generate 12 transgenic lines. Eight of the 12 lines, including 5 of 5 derived from one construct with an intron, express detectable fluorescence in the F1 and, where tested, in the F2 generation. Most expressing lines showed very similar expression patterns. Generally, fluorescence is not seen in the transgenic embryos before 20 hr postfertilization, at which point it appears uniformly throughout the embryo. Fluorescence is most visible between 24-36 hr, and it becomes less visible after this, except that in many lines strong fluorescence remains visible in the eye for at least 5 days. A single inherited copy of the transgene is sufficient to produce detectable fluorescence in hemizygous F1 and F2 embryos.

  4. Probing the role of tryptophans in Aequorea victoria green fluorescent proteins with an expanded genetic code.

    PubMed

    Budisa, Nediljko; Pal, Prajna Paramita; Alefelder, Stefan; Birle, Petra; Krywcun, Tatjana; Rubini, Marina; Wenger, Waltraud; Bae, Jae Hyun; Steiner, Thomas

    2004-02-01

    The expanded genetic code in combination with site-directed mutagenesis was used to probe spectroscopic and structural roles of tryptophan (Trp) residues in Aequorea victoria green fluorescent proteins (avGFPs). Nine different halogen-, chalcogen-, and methyl-containing Trp isosteric analogues and surrogates were incorporated into avGFPs containing indole moieties in, and outside of, the chromophore, by the use of the selective pressure incorporation method. Such isosteric replacements introduced minimal local geometry changes in indole moieties, often to the level of single atomic exchange ('atomic mutation') and do not affect three-dimensional structures of avGFPs but induce changes in spectral properties. Our approach offers a new platform to re-evaluate issues like resonance transfer, mechanisms of chromophore formation and maturation, as well as the importance of local geometry and weak sulphur-aromatic interactions for avGFP spectral properties and structural stability. The library of novel tailor-made avGFP mutants and variants generated in this work has demonstrated not only the potentials of the expanded genetic code to study spectroscopic functions, but also a new approach to generate tailor-made proteins with interesting and useful spectral properties.

  5. Effect of fixation procedures on the fluorescence lifetimes of Aequorea victoria derived fluorescent proteins.

    PubMed

    Joosen, L; Hink, M A; Gadella, T W J; Goedhart, J

    2014-12-01

    Fluorescence lifetime imaging microscopy can be used to study protein-protein interactions by Förster Resonance Energy Transfer or to perform lifetime-based multiplexing. Fixation of samples with cells producing fluorescent fusion proteins is commonly used for preservation of samples and for staining with membrane impermeable reagents such as antibodies. However, the effect of fixation methods and mounting media on fluorescence lifetime is poorly documented so far. Here, we demonstrate that fixation by formaldehyde or methanol itself does not affect the lifetime of fluorescent proteins produced in cells but that several widely used mounting media decrease the fluorescence lifetime by up to 20%. It is shown that fixed cells producing Aequorea victoria derived fluorescent proteins mounted in Tris buffer have fluorescence lifetimes indistinguishable from values measured in living cells. Tris buffer also allows accurate Förster Resonance Energy Transfer quantification in fixed cells, as shown with an mTurquoise2-SYFP2 fusion protein. Moreover, identical lifetime contrasts are measured in living and fixed cells mounted in Tris buffer after introducing a single plasmid expressing two lifetime variants of cyan fluorescent proteins, each targeted to different locations in the cell. Our findings will aid the preparation of fixed cells producing fluorescent proteins for reliable measurement of fluorescence lifetimes for Förster Resonance Energy Transfer determination, lifetime based multiplexing and for instrument calibration for standardization purposes.

  6. Examination of Listeria monocytogenes intracellular gene expression by using the green fluorescent protein of Aequorea victoria.

    PubMed

    Freitag, N E; Jacobs, K E

    1999-04-01

    The ActA protein of Listeria monocytogenes is an essential virulence factor and is required for intracellular bacterial motility and cell-to-cell spread. plcB, cotranscribed with actA, encodes a broad-specificity phospholipase C that contributes to lysis of host cell vacuoles and cell-to-cell spread. Construction of a transcriptional fusion between actA-plcB and the green fluorescent protein gene of Aequorea victoria has facilitated the detailed examination of patterns of actA/plcB expression within infected tissue culture cells. actA/plcB expression began approximately 30 min postinfection and was dependent upon entry of L. monocytogenes into the host cytosol. L. monocytogenes Deltahly mutants, which are unable to escape from host cell vacuoles, did not express actA/plcB at detectable levels within infected tissue culture cells; however, complementation of the hly defect allowed entry of the bacteria into the host cytoplasm and subsequent actA/plcB expression. These results emphasize the ability of L. monocytogenes to sense the different host cell compartment environments encountered during the course of infection and to regulate virulence gene expression in response.

  7. Bacterial plasmid conjugation on semi-solid surfaces monitored with the green fluorescent protein (GFP) from Aequorea victoria as a marker.

    PubMed

    Christensen, B B; Sternberg, C; Molin, S

    1996-01-01

    Horizontal transfer of the TOL plasmid was examined in Pseudomonas putida (Pp) KT2442 micro-colonies on semi-solid agar surfaces. Horizontal gene transfer is usually studied in large populations where all information is based on average estimates of the transfer events in the entire population. We have used the green fluorescent protein (GFP) from the jellyfish Aequorea victoria as a plasmid marker, in combination with single-cell observations. This provided hitherto unknown details on the distribution of cells active in conjugation. In the present study, donor cells containing the gfp gene expressed from the bacteriophage T7 phi 10 promoter on the TOL plasmid, and recipient cells expressing the corresponding phage RNA polymerase allowed us to monitor the occurrence of ex-conjugants as green fluorescent cells upon illumination with blue light (470-490 nm). Further, the recipients were labeled with the luxAB genes to distinguish micro-colonies of donor cells from recipient cells. We conclude that conjugal plasmid transfer in Pp KT2442 cells on semi-solid surfaces occurs mainly during a short period of time after the initial contact of donors and recipients, indicating that spread of the TOL plasmid is limited in static, but viable cultures.

  8. The numerical comparison of flow patterns and propulsive performances for the hydromedusae Sarsia tubulosa and Aequorea victoria.

    PubMed

    Sahin, Mehmet; Mohseni, Kamran; Colin, Sean P

    2009-08-01

    The thrust-generating mechanism of a prolate hydromedusa Sarsia tubulosa and an oblate hydromedusa Aequorea victoria was investigated by solving the incompressible Navier-Stokes equations in the swirl-free cylindrical coordinates. The calculations clearly show the vortex dynamics related to the thrust-generating mechanism, which is very important for understanding the underlying propulsion mechanism. The calculations for the prolate jetting hydromedusa S. tubulosa indicate the formation of a single starting vortex ring for each pulse cycle with a relatively high vortex formation number. However, the calculations for the oblate jet-paddling hydromedusa A. victoria indicate shedding of the opposite-signed vortex rings very close to each other and the formation of large induced velocities along the line of interaction as the vortices move away from the hydromedusa in the wake. In addition to this jet propulsion mechanism, the hydromedusa's bell margin acts like a paddle and the highly flexible bell margin deforms in such a way that the low pressure leeward side of the bell margin has a projected area in the direction of motion. This thrust is particularly important during refilling of the subumbrella cavity where the stopping vortex causes significant pressure drag. The swimming performances based on our numerical simulations, such as swimming velocity, thrust, power requirement and efficiency, were computed and support the idea that jet propulsion is very effective for rapid body movement but is energetically costly and less efficient compared with the jet-paddling propulsion mechanism.

  9. Structure of a fluorescent protein from Aequorea victoria bearing the obligate-monomer mutation A206K.

    PubMed

    von Stetten, David; Noirclerc-Savoye, Marjolaine; Goedhart, Joachim; Gadella, Theodorus W J; Royant, Antoine

    2012-08-01

    The green fluorescent protein (GFP) from the jellyfish Aequoria victoria has been shown to dimerize at high concentrations, which could lead to artefacts in imaging experiments. To ensure a truly monomeric state, an A206K mutation has been introduced into most of its widely used variants, with minimal effect on the spectroscopic properties. Here, the first structure of one of these variants, the cyan fluorescent protein mTurquoise, is presented and compared with that of its dimeric version mTurquoise-K206A. No significant structural change is detected in the chromophore cavity, reinforcing the notion that this mutation is spectroscopically silent and validating that the structural analysis performed on dimeric mutants also applies to monomeric versions. Finally, it is explained why cyan versions of GFP containing the Y66W and N146I mutations do not require the A206K mutation to prevent dimerization at high concentrations.

  10. Reversible dimerization of Aequorea victoria fluorescent proteins increases the dynamic range of FRET-based indicators.

    PubMed

    Kotera, Ippei; Iwasaki, Takuya; Imamura, Hiromi; Noji, Hiroyuki; Nagai, Takeharu

    2010-02-19

    Fluorescent protein (FP)-based Forster resonance energy transfer (FRET) technology is useful for development of functional indicators to visualize second messenger molecules and activation of signaling components in living cells. However, the design and construction of the functional indicators require careful optimization of their structure at the atomic level. Therefore, routine procedures for constructing FRET-based indicators currently include the adjustment of the linker length between the FPs and the sensor domain and relative dipole orientation of the FP chromophore. Here we report that, in addition to these techniques, optimization of the dimerization interface of Aequorea FPs is essential to achieve the highest possible dynamic range of signal change by FRET-based indicators. We performed spectroscopic analyses of various indicators (cameleon, TN-XL, and ATeam) and their variants. We chose variants containing mutant FPs with different dimerization properties, i.e., no, weak, or enhanced dimerization of the donor or acceptor FP. Our findings revealed that the FPs that dimerized weakly yielded high-performance FRET-based indicators with the greatest dynamic range.

  11. [Expression of green fluorescent protein (GFP) gene of Aequorea victoria [correction of Aequoria victoria] in Lactobacillus plantarum bacterium ].

    PubMed

    Shkoporov, A N; Khokhlova, E V; Efimov, B A; Kafarskaia, L I

    2008-01-01

    Results of development of shuttle expressing plasmid vector Escherichia coli-Lactobacillus which allowed high level expression of heterologous genes in lactobacilli are represented. Vector pTRKH2 which is able to replicate in E. coli and in wide range of Gram-positive bacteria was used as the base. In order to provide high level of cloned gene expression constitutive-active synthetic promoter, site of initiation of translation, and terminator of transcription were introduced in the vector. Functional activity of this vector was confirmed using green fluorescent protein (GFP) gene from Aequoria victoria. Transformation of model strain by gfp gene-carrying plasmid resulted in appearance of typical fluorescent phenotype.

  12. A bio-inspired bell kinematics design of a jellyfish robot using ionic polymer metal composites actuators

    NASA Astrophysics Data System (ADS)

    Najem, Joseph; Leo, Donald J.

    2012-04-01

    This paper presents the re-creation of the bell deformation cycle of the Aequorea victoria jellyfish. It focuses on the design, fabrication, and characterization of the bio-inspired bell kinematics of an IPMC actuated robotic jellyfish. The shape and bell kinematics of this underwater vehicle are based on the Aequorea victoria jellyfish. This medusa is chosen as a model system based on a comparative bell kinematics study that is conducted among different jellyfish species. Aequorea victoria is known by its low swimming frequency, small bell deformation, and high Froude efficiency (95%). Different methods of implementing the actuators underneath the bell with smaller IPMC actuators are investigated to replicate the natural jellyfish's bell deformation. Results demonstrates that proper placement of the IPMC actuators results in bell configuration that more accurately represents the deformation properties of the natural jellyfish. Smaller IPMC actuators are used to achieve the desired deformation and thus the power consumption is reduced by 70% compared to previous generations. A biomimetic jellyfish robot prototype is built, and its ability to swim and produce thrust with smaller IPMC actuators is shown. The robot swam with four actuators swam at an average speed 0.77 mm/s and consumed 0.7 W. When eight actuators were used the average speed increased to 1.5 mm/s with a power consumption of 1.14 W.

  13. Enhanced green fluorescence by the expression of an Aequorea victoria green fluorescent protein mutant in mono- and dicotyledonous plant cells.

    PubMed

    Reichel, C; Mathur, J; Eckes, P; Langenkemper, K; Koncz, C; Schell, J; Reiss, B; Maas, C

    1996-06-11

    The expression of the jellyfish green fluorescent protein (GFP) in plants was analyzed by transient expression in protoplasts from Nicotiana tabacum, Arabidopsis thaliana, Hordeum vulgare, and Zea mays. Expression of GFP was only observed with a mutated cDNA, from which a recently described cryptic splice site had been removed. However, detectable levels of green fluorescence were only emitted from a small number of protoplasts. Therefore, other mutations in the GFP cDNA leading to single-amino acid exchanges in the chromophore region, which had been previously studied in Escherichia coli, were tested in order to improve the sensitivity of this marker protein. Of the mutations tested so far, the exchange of GFP amino acid tyrosine 66 to histidine (Y66H) led to detection of blue fluorescence in plant protoplasts, while the exchange of amino acid serine 65 to cysteine (S65C) and threonine (S65T) increased the intensity of green fluorescence drastically, thereby significantly raising the detection level for GFP. For GFP S65C, the detectable number of green fluorescing tobacco (BY-2) protoplasts was raised up to 19-fold, while the fluorimetricly determined fluorescence was raised by at least 2 orders of magnitude.

  14. Milbemycin oxime (Interceptor) treatment of amphipod parasites (Hyperiidae) from several host jellyfish species.

    PubMed

    Boonstra, Jennifer L; Koneval, Maureen E; Clark, James D; Schick, Mark; Smith, Malissa; Stark, Amy L

    2015-03-01

    Wild-caught crystal jellyfish (Aequorea victoria) arrived at the John G. Shedd Aquarium infested with hyperiid amphipods (Hyperia medusarum), which were inadvertently introduced into a system containing several jellyfish species. Affected systems were treated with milbemycin oxime (Interceptor tablets for dogs 51-100 lbs, Novartis Animal Health US, Inc., Greensboro, North Carolina 27408, USA), a treatment prescribed for red bug (Tegastes acroporanus) infestation in corals. Two treatments using one 25-mg aliquot of Interceptor per 10 gallons of tank water administered 6-7 days apart were completed. Overall, treatment to eradicate the parasite from the affected systems was successful. Further studies evaluating the tolerance of jellyfish to milbemycin oxime, particularly in small juvenile Eutonina indicans and Aurelia aurita, are warranted. Based on clinical observations, there were more negative effects associated with the treatment in the hydrozoans than in the scyphozoans.

  15. Aequorea green fluorescent protein analysis by flow cytometry.

    PubMed

    Ropp, J D; Donahue, C J; Wolfgang-Kimball, D; Hooley, J J; Chin, J Y; Hoffman, R A; Cuthbertson, R A; Bauer, K D

    1995-12-01

    The isolation and expression of the cDNA for the green fluorescent protein (GFP) from the bioluminescent jellyfish Aequorea victoria has highlighted its potential use as a marker for gene expression in a variety of cell types (Chalfie et al.: Science 263: 802-805, 1994). The longer wavelength peak (470 nm) of GFP's bimodal absorption spectrum better matches standard fluorescein filter sets; however, it has a considerably lower amplitude than the major absorption peak at 395. In an effort to increase the sensitivity of GFP with routinely available instrumentation, Heim et al. (Nature 373:663-664, 1995) have generated a GFP mutant (serine-65 to threonine; S65T-GFP) which possesses a single absorption peak centered at 490 nm. We have constructed this mutant in order to determine whether it or wild-type GFP (wt-GFP) afforded greater sensitivity when excited near their respective absorption maxima. Using the conventionally available 488 nm and ultraviolet (UV) laser lines from the argon ion laser as well as the 407 nm line from a krypton ion laser with enhanced violet emission, we were able to closely match the absorption maxima of both the S65T and wild-type forms of Aequorea GFP and analyze differences in fluorescence intensity of transiently transfected 293 cells with flow cytometry. The highest fluorescence signal was observed with 488 nm excitation of S65T-GFP relative to all other laser line/GFP pairs. The wt-GFP fluorescence intensity, in contrast, was significantly higher at 407 nm relative to either 488 nm or UV. These results were consistent with parallel spectrofluorometric analysis of the emission spectrum for wt-GFP and S65T-GFP. The relative contribution of cellular autofluorescence at each wavelength was also investigated and shown to be significantly reduced at 407 nm relative to either UV or 488 nm.

  16. Aequorea green fluorescent protein analysis by flow cytometry

    SciTech Connect

    Ropp, J.D.; Cuthbertson, R.A.; Donahue, C.J.; Wolfgang-Kimball, D.

    1995-12-01

    The isolation and expression of the cDNA for the green fluorescent protein (GFP) from the bioluminescent jellyfish Aequorea victoria has highlighted its potential use as a marker for gene expression in a variety of cell types. The longer wavelength peak (470 nm) of GFP`s bimodal absorption spectrum better matches standard fluorescein filter sets; however, it has a considerably lower amplitude than the major absorption peak at 395. In an effort to increase the sensitivity of GFP with routinely available instrumentation, Heim et al. have generated a GFP mutant (serine-65 to threonine; S65T-GFP) which possesses a single absorption peak centered at 490 nm. We have constructed this mutant in order to determine whether it or wild-type GFP (wt-GFP) afforded greater sensitivity when excited near their respective absorption maxima. Using the conventionally available 488 nm and ultraviolet (UV) laser lines from the argon ion laser as well as the 407 nm line from a krypton ion laser with enhanced violet emission, we were able to closely match the absorption maxima of both the S65T and wild-type forms of Aequorea GFP and analyze differences in fluorescence intensity of transiently transfected 293 cells with flow cytometry. The highest fluorescence signal was observed with 488 nm excitation of S65T-GFP relative to all other laser line/GFP pairs. The wt-GFP fluorescence intensity, in contrast, was significantly higher at 407 nm relative to either 488 nm or UV. These results were consistent with parallel spectrofluorometric analysis of the emission spectrum for wt-GFP and S65T- GFP. The relative contribution of cellular autofluorescence at each wavelength was also investigated and shown to be significantly reduced at 407 nm relative to either UV or 488 nm. 29 refs., 5 figs.

  17. Crystallization and preliminary X-ray analysis of a monomeric mutant of Azami-Green (mAG), an Aequorea victoria green fluorescent protein-like green-emitting fluorescent protein from the stony coral Galaxea fascicularis

    PubMed Central

    Ebisawa, Tatsuki; Yamamura, Akihiro; Kameda, Yasuhiro; Hayakawa, Kou; Nagata, Koji; Tanokura, Masaru

    2009-01-01

    Monomeric Azami-Green (mAG) from the stony coral Galaxea fascicularis is the first monomeric green-emitting fluorescent protein that is not a derivative of Aequorea victoria green fluorescent protein (avGFP). mAG and avGFP are 27% identical in amino-acid sequence. Diffraction-quality crystals of recombinant mAG were obtained by the sitting-drop vapour-diffusion method using PEG 3350 as the precipitant. The mAG crystal diffracted X-rays to 2.20 Å resolution on beamline AR-NW12A at the Photon Factory (Tsukuba, Japan). The crystal belonged to space group P1, with unit-cell parameters a = 41.78, b = 51.72, c = 52.89 Å, α = 90.96, β = 103.41, γ = 101.79°. The Matthews coefficient (V M = 2.10 Å3 Da−1) indicated that the crystal contained two mAG molecules per asymmetric unit. PMID:20054132

  18. Crystallization and preliminary X-ray analysis of a monomeric mutant of Azami-Green (mAG), an Aequorea victoria green fluorescent protein-like green-emitting fluorescent protein from the stony coral Galaxea fascicularis.

    PubMed

    Ebisawa, Tatsuki; Yamamura, Akihiro; Kameda, Yasuhiro; Hayakawa, Kou; Nagata, Koji; Tanokura, Masaru

    2009-12-01

    Monomeric Azami-Green (mAG) from the stony coral Galaxea fascicularis is the first monomeric green-emitting fluorescent protein that is not a derivative of Aequorea victoria green fluorescent protein (avGFP). mAG and avGFP are 27% identical in amino-acid sequence. Diffraction-quality crystals of recombinant mAG were obtained by the sitting-drop vapour-diffusion method using PEG 3350 as the precipitant. The mAG crystal diffracted X-rays to 2.20 A resolution on beamline AR-NW12A at the Photon Factory (Tsukuba, Japan). The crystal belonged to space group P1, with unit-cell parameters a = 41.78, b = 51.72, c = 52.89 A, alpha = 90.96, beta = 103.41, gamma = 101.79 degrees. The Matthews coefficient (V(M) = 2.10 A(3) Da(-1)) indicated that the crystal contained two mAG molecules per asymmetric unit.

  19. X-ray diffraction and time-resolved fluorescence analyses of Aequorea green fluorescent protein crystals.

    PubMed

    Perozzo, M A; Ward, K B; Thompson, R B; Ward, W W

    1988-06-05

    The energy transfer protein, green fluorescent protein, from the hydromedusan jellyfish Aequorea victoria has been crystallized in two morphologies suitable for x-ray diffraction analysis. Hexagonal plates have been obtained in the P6122 or P6522 space group with a = b = 77.5, c = 370 A, and no more than three molecules per asymmetric unit. Monoclinic parallel-epipeds have been obtained in the C2 space group with a = 93.3, b = 66.5, c = 45.5 A, beta = 108 degrees, and one molecule per asymmetric unit. The monoclinic form is better suited for use in a structure determination, and a data set was collected from the native crystal. Time-resolved fluorescence measurements of large single crystals are possible due to the unique, covalently bound chromophore present in this molecule. Fluorescence emission spectra of Aequorea green fluorescent protein in solution and from either the hexagonal or monoclinic single crystal show similar profiles suggesting that the conformations of protein in solution and in the crystal are similar. Multifrequency phase fluorimetric data obtained from a single crystal were best fit by a single fluorescence lifetime very close to that exhibited by the protein in solution. The complementary structural data obtained from fluorescence spectroscopy and x-ray diffraction crystallography will aid in the elucidation of this novel protein's structure-function relationship.

  20. Biomimetic jellyfish-inspired underwater vehicle actuated by ionic polymer metal composite actuators

    NASA Astrophysics Data System (ADS)

    Najem, Joseph; Sarles, Stephen A.; Akle, Barbar; Leo, Donald J.

    2012-09-01

    This paper presents the design, fabrication, and characterization of a biomimetic jellyfish robot that uses ionic polymer metal composites (IPMCs) as flexible actuators for propulsion. The shape and swimming style of this underwater vehicle are based on the Aequorea victoria jellyfish, which has an average swimming speed of 20 mm s-1 and which is known for its high swimming efficiency. The Aequorea victoria is chosen as a model system because both its bell morphology and kinematic properties match the mechanical properties of IPMC actuators. This medusa is characterized by its low swimming frequency, small bell deformation during the contraction phase, and high Froude efficiency. The critical components of the robot include the flexible bell that provides the overall shape and dimensions of the jellyfish, a central hub and a stage used to provide electrical connections and mechanical support to the actuators, eight distinct spars meant to keep the upper part of the bell stationary, and flexible IPMC actuators that extend radially from the central stage. The bell is fabricated from a commercially available heat-shrinkable polymer film to provide increased shape-holding ability and reduced weight. The IPMC actuators constructed for this study demonstrated peak-to-peak strains of ˜0.7% in water across a frequency range of 0.1-1.0 Hz. By tailoring the applied voltage waveform and the flexibility of the bell, the completed robotic jellyfish with four actuators swam at an average speed 0.77 mm s-1 and consumed 0.7 W. When eight actuators were used the average speed increased to 1.5 mm s-1 with a power consumption of 1.14 W.

  1. Chemical nature of the light emitter of the Aequorea green fluorescent protein.

    PubMed

    Niwa, H; Inouye, S; Hirano, T; Matsuno, T; Kojima, S; Kubota, M; Ohashi, M; Tsuji, F I

    1996-11-26

    The jellyfish Aequorea victoria possesses in the margin of its umbrella a green fluorescent protein (GFP, 27 kDa) that serves as the ultimate light emitter in the bioluminescence reaction of the animal. The protein is made up of 238 amino acid residues in a single polypeptide chain and produces a greenish fluorescence (lambda max = 508 nm) when irradiated with long ultraviolet light. The fluorescence is due to the presence of a chromophore consisting of an imidazolone ring, formed by a post-translational modification of the tripeptide -Ser65-Tyr66-Gly67-. GFP has been used extensively as a reporter protein for monitoring gene expression in eukaryotic and prokaryotic cells, but relatively little is known about the chemical mechanism by which fluorescence is produced. To obtain a better understanding of this problem, we studied a peptide fragment of GFP bearing the chromophore and a synthetic model compound of the chromophore. The results indicate that the GFP chromophore consists of an imidazolone ring structure and that the light emitter is the singlet excited state of the phenolate anion of the chromophore. Further, the light emission is highly dependent on the microenvironment around the chromophore and that inhibition of isomerization of the exo-methylene double bond of the chromophore accounts for its efficient light emission.

  2. From jellyfish to biosensors: the use of fluorescent proteins in plants.

    PubMed

    Voss, Ute; Larrieu, Antoine; Wells, Darren M

    2013-01-01

    The milestone discovery of green fluorescent protein (GFP) from the jellyfish Aequorea victoria, its optimisation for efficient use in plantae, and subsequent improvements in techniques for fluorescent detection and quantification have changed plant molecular biology research dramatically. Using fluorescent protein tags allows the temporal and spatial monitoring of dynamic expression patterns at tissue, cellular and subcellular scales. Genetically-encoded fluorescence has become the basis for applications such as cell-type specific transcriptomics, monitoring cell fate and identity during development of individual organs or embryos, and visualising protein-protein interactions in vivo. In this article, we will give an overview of currently available fluorescent proteins, their applications in plant research, the techniques used to analyse them and, using the recent development of an auxin sensor as an example, discuss the design principles and prospects for the next generation of fluorescent plant biosensors.

  3. Use of the A. victoria green fluorescent protein to study protein dynamics in vivo.

    PubMed

    Kahana, J A; Silver, P A

    2001-05-01

    Fluorescent molecules serve as valuable tools for the detection of a variety of biochemical phenomena. Such reagents have been employed for protein localization, quantitation of gene expression, detection of nucleic acids, cell sorting, and determination of chemical concentrations. Although fluorescence is a useful tool for detecting molecules within cells, its application in vivo has been limited. The ideal vital fluorescent tag should (1) be detectable without causing cytological damage, (2) be able to label a wide variety of cell types readily, and (3) be able to be targeted to virtually any subcellular region. The recently cloned green fluorescent protein (GFP) from the jellyfish Aequorea victoria is such a molecule. This overview describes the use of this proteinaceous fluorophore for in vivo observation of cellular phenomena, including applications and problems with the use of GFP, a discussion of mutant GFPs with altered fluorescence characteristics, and also some details on microscopy requirements.

  4. Use of the A. victoria green fluorescent protein to study protein dynamics in vivo.

    PubMed

    Kahana, J A; Silver, P A

    2001-05-01

    Fluorescent molecules serve as valuable tools for the detection of a variety of biochemical phenomena. Such reagents have been employed for protein localization, quantitation of gene expression, detection of nucleic acids, cell sorting, and determination of chemical concentrations. Although fluorescence is a useful tool for detecting molecules within cells, its application in vivo has heretofore been limited. The ideal vital fluorescent tag should (1) be detectable without causing cytological damage, (2) be able to label a wide variety of cell types readily, and (3) be able to be targeted to virtually any subcellular region. The recently cloned green fluorescent protein (GFP) from the jellyfish Aequorea victoria is such a molecule. This overview describes the use of this proteinaceous fluorophore for in vivo observation of cellular phenomena, including applications and problems with the use of GFP, a discussion of mutant GFPs with altered fluorescence characteristics, and also some details on microscopy requirements.

  5. Early history, discovery, and expression of Aequorea green fluorescent protein, with a note on an unfinished experiment.

    PubMed

    Tsuji, Frederick I

    2010-08-01

    The bioluminescent hydromedusan jellyfish, Aequorea victoria, emits a greenish light (lambda(max) = 508 nm) when stimulated electrically or mechanically. The light comes from photocytes located along the margin of its umbrella. The greenish light depends on two intracellular proteins working in consort: aequorin (21.4 kDa) and a green fluorescent protein (27 kDa). An excited state green fluorescent protein molecule results, which, on returning to the ground state, emits a greenish light. Similarly, a green light emission may be induced in the green fluorescent protein by exposing it to ultraviolet or blue light. Because the green light can be readily detected under a fluorescence microscope, the green fluorescent protein, tagged to a protein of interest, has been used widely as a marker to locate proteins in cells and to monitoring gene expression. This article reviews the work that took place leading to the discovery, cloning, and expression of the green fluorescent protein, with a note on an unfinished experiment.

  6. Expression of Aequorea green fluorescent protein in plant cells.

    PubMed

    Hu, W; Cheng, C L

    1995-08-07

    The coding region of the green fluorescent protein (GFP) from Aequorea victoria has been fused to the cauliflower mosaic virus 35S promoter and introduced into maize leaf protoplasts. Transient expression of GFP was observed. In addition, the coding region of GFP was fused to an Arabidopsis heat shock promoter and co-transformed with another construct in which GFP has been replaced with chloramphenicol acetyltransferase (CAT). The heat-induced expression of GFP in maize protoplasts parallels that of CAT. While GFP was expressed in both dark-grown and green maize leaf protoplasts, no green fluorescence was observed in similarly transformed Arabidopsis protoplasts.

  7. Subcellular calcium measurements in mammalian cells using jellyfish photoprotein aequorin-based probes.

    PubMed

    Bonora, Massimo; Giorgi, Carlotta; Bononi, Angela; Marchi, Saverio; Patergnani, Simone; Rimessi, Alessandro; Rizzuto, Rosario; Pinton, Paolo

    2013-11-01

    The jellyfish Aequorea victoria produces a 22-kDa protein named aequorin that has had an important role in the study of calcium (Ca(2+)) signaling. Aequorin reacts with Ca(2+) via oxidation of the prosthetic group, coelenterazine, which results in emission of light. This signal can be detected by using a special luminescence reader (called aequorinometer) or luminescence plate readers. Here we describe the main characteristics of aequorin as a Ca(2+) probe and how to measure Ca(2+) in different intracellular compartments of animal cells (cytosol, different mitochondrial districts, nucleus, endoplasmic reticulum (ER), Golgi apparatus, peroxisomes and subplasma-membrane cytosol), ranging from single-well analyses to high-throughput screening by transfecting animal cells using DNA vectors carrying recombinant aequorin chimeras. The use of aequorin mutants and modified versions of coelenterazione increases the range of calcium concentrations that can be recorded. Cell culture and transfection takes ∼3 d. An experiment including signal calibration and the subsequent analyses will take ∼1 d.

  8. Synthetic Biomimetic Fluorophores for Micro/Nanosensor

    DTIC Science & Technology

    2006-11-01

    as a companion protein to aequorin, the famous chemiluminescent protein from the brightly luminescent Aequorea jellyfish , with glowing points...peaked near 470 nm, which was close to one of the excitation peaks of GFP. Aequorin, isolated from the jellyfish Aequorea victoria, is a complex of...partially homologous to green fluorescent protein (GFP) (Matz et al. 1999, Dove et al. 2000), first found in the luminescent jellyfish Aequorea and used

  9. The role of localized cell surface-associated glycoproteins during fertilization in the hydrozoan Aequorea.

    PubMed

    Freeman, G

    1996-10-10

    Hydrozoan eggs can be fertilized only at the site of polar body formation and first acquire this ability during second polar body formation. The eggs of Aequorea victoria form a discrete Triticum lectin binding moiety in the jelly coat near the first polar body as it is being given off and also a discrete concanavalin A binding moiety associated with the egg surface where the second polar body forms, which disappears immediately after fertilization. The germinal vesicle has an eccentric position in full grown Aequorea oocytes. The region of oocyte surface closest to the germinal vesicle is the site where the polar bodies normally form. When oocytes are centrifuged during oocyte maturation, the meiotic apparatus sometimes shifts to a different position with reference to the egg surface and polar bodies are given off at this new site. There is a corresponding shift in the position of the Triticum and concanavalin A lectin binding moieties, indicating that their formation is associated with local events occurring at the site of polar body formation. Treatment of Aequorea eggs with Triticum or concanavalin A causes a marked reduction in the ability of these eggs to be fertilized, suggesting that sugar-containing moieties, to which the lectins bind, play a role in fertilization. Removal of sugars on these moieties with mannosidase or N-acetylglucosaminidase, or the cleavage of the protein the sugars are attached to with trypsin, results in eggs that do not bind Triticum or concanavalin A and also show a marked reduction in the ability to be fertilized. These experiments suggest that the lectin binding moieties are glycoproteins.

  10. Chemical structure of the hexapeptide chromophore of the Aequorea green-fluorescent protein.

    PubMed

    Cody, C W; Prasher, D C; Westler, W M; Prendergast, F G; Ward, W W

    1993-02-09

    The green-fluorescent proteins (GFP) are a unique class of proteins involved in bioluminescence of many cnidaria. The GFPs serve as energy-transfer acceptors, receiving energy from either a luciferase-oxyluciferin complex or a Ca(2+)-activated photoprotein, depending on the organism. Upon mechanical stimulation of the organism, GFP emits green light spectrally identical to its fluorescence emission. These highly fluorescent proteins are unique due to the nature of the covalently attached chromophore, which is composed of modified amino acid residues within the polypeptide. This report describes the characterization of the Aequorea victoria GFP chromophore which is released as a hexapeptide upon digestion of the protein with papain. The chromophore is formed upon cyclization of the residues Ser-dehydroTyr-Gly within the polypeptide. The chromophore structure proposed here differs from that described by Shimomura [(1979) FEBS Lett. 104, 220] in a number of ways.

  11. More on that jellyfish

    NASA Astrophysics Data System (ADS)

    Pataky, Lucky; edprochack

    2014-03-01

    This jellyfish-like flying machine (built by Leif Ristroph and Stephen Childress of New York University) can hover and stabilize itself in flight with no feedback control ("Flying 'jellyfish' is self-stabilizing", 16 January http://ow.ly/tl63X; see also p5).

  12. The Role of Protein Kinase-C in Breast Cancer Invasion and Metastasis

    DTIC Science & Technology

    1997-09-01

    the jellyfish Aequorea victoria . A modified form of this protein has been generated that has altered excitation and emission spectra so that it...relatively new reporter molecule that is being increasingly used in a variety of studies is the green fluorescent protein (GFP) from the jellyfish Aequorea ... victoria . A modified form of this protein has been generated that has altered excitation and emission spectra so that it works well with detection

  13. Victoria Cowling.

    PubMed

    Cowling, Victoria; Bobrowska, Anna

    2015-08-15

    Victoria Cowling received her BA from the University of Cambridge. She completed her PhD with Julian Downward and Gerard Evan at Cancer Research UK in London, and then moved to the US for a postdoctoral position at Princeton University and Dartmouth College with Michael Cole. Since 2008, she has been running a lab at Dundee University. She is an MRC Senior Research Fellow, a Lister Institute Research Fellow and an EMBO Young Investigator and, in 2015, she was the first recipient of the Women in Cell Biology medal, awarded by the British Society for Cell Biology.

  14. Dimerization between aequorea fluorescent proteins does not affect interaction between tagged estrogen receptors in living cells.

    PubMed

    Kofoed, Eric M; Guerbadot, Martin; Schaufele, Fred

    2008-01-01

    Forster resonance energy transfer (FRET) detection of protein interaction in living cells is commonly measured following the expression of interacting proteins genetically fused to the cyan (CFP) and yellow (YFP) derivatives of the Aequorea victoria fluorescent protein (FP). These FPs can dimerize at mM concentrations, which may introduce artifacts into the measurement of interaction between proteins that are fused with the FPs. Here, FRET analysis of the interaction between estrogen receptors (alpha isoform, ERalpha) labeled with "wild-type" CFP and YFP is compared with that of ERalpha labeled with "monomeric" A206K mutants of CFP and YFP. The intracellular equilibrium dissociation constant for the hormone-induced ERalpha-ERalpha interaction is similar for ERalpha labeled with wild-type or monomeric FPs. However, the measurement of energy transfer measured for ERalpha-ERalpha interaction in each cell is less consistent with the monomeric FPs. Thus, dimerization of the FPs does not affect the kinetics of ERalpha-ERalpha interaction but, when brought close together via ERalpha-ERalpha interaction, FP dimerization modestly improves FRET measurement.

  15. Structural basis for dual excitation and photoisomerization of the Aequorea victoria green fluorescent protein.

    PubMed

    Brejc, K; Sixma, T K; Kitts, P A; Kain, S R; Tsien, R Y; Ormö, M; Remington, S J

    1997-03-18

    The 2.1-A resolution crystal structure of wild-type green fluorescent protein and comparison of it with the recently determined structure of the Ser-65 --> Thr (S65T) mutant explains the dual wavelength absorption and photoisomerization properties of the wild-type protein. The two absorption maxima are caused by a change in the ionization state of the chromophore. The equilibrium between these states appears to be governed by a hydrogen bond network that permits proton transfer between the chromophore and neighboring side chains. The predominant neutral form of the fluorophore maximally absorbs at 395 nm. It is maintained by the carboxylate of Glu-222 through electrostatic repulsion and hydrogen bonding via a bound water molecule and Ser-205. The ionized form of the fluorophore, absorbing at 475 nm, is present in a minor fraction of the native protein. Glu-222 donates its charge to the fluorophore by proton abstraction through a hydrogen bond network, involving Ser-205 and bound water. Further stabilization of the ionized state of the fluorophore occurs through a rearrangement of the side chains of Thr-203 and His-148. UV irradiation shifts the ratio of the two absorption maxima by pumping a proton relay from the neutral chromophore's excited state to Glu-222. Loss of the Ser-205-Glu-222 hydrogen bond and isomerization of neutral Glu-222 explains the slow return to the equilibrium dark-adapted state of the chromophore. In the S65T structure, steric hindrance by the extra methyl group stabilizes a hydrogen bonding network, which prevents ionization of Glu-222. Therefore the fluorophore is permanently ionized, causing only a 489-nm excitation peak. This new understanding of proton redistribution in green fluorescent protein should enable engineering of environmentally sensitive fluorescent indicators and UV-triggered fluorescent markers of protein diffusion and trafficking in living cells.

  16. Structural Basis for Dual Excitation and Photoisomerization of the Aequorea victoria Green Fluorescent Protein

    NASA Astrophysics Data System (ADS)

    Brejc, Katjusa; Sixma, Titia K.; Kitts, Paul A.; Kain, Steven R.; Tsien, Roger Y.; Ormo, Mats; Remington, S. James

    1997-03-01

    The 2.1- angstrom resolution crystal structure of wild-type green fluorescent protein and comparison of it with the recently determined structure of the Ser-65 --> Thr (S65T) mutant explains the dual wavelength absorption and photoisomerization properties of the wild-type protein. The two absorption maxima are caused by a change in the ionization state of the chromophore. The equilibrium between these states appears to be governed by a hydrogen bond network that permits proton transfer between the chromophore and neighboring side chains. The predominant neutral form of the fluorophore maximally absorbs at 395 nm. It is maintained by the carboxylate of Glu-222 through electrostatic repulsion and hydrogen bonding via a bound water molecule and Ser-205. The ionized form of the fluorophore, absorbing at 475 nm, is present in a minor fraction of the native protein. Glu-222 donates its charge to the fluorophore by proton abstraction through a hydrogen bond network, involving Ser-205 and bound water. Further stabilization of the ionized state of the fluorophore occurs through a rearrangement of the side chains of Thr-203 and His-148. UV irradiation shifts the ratio of the two absorption maxima by pumping a proton relay from the neutral chromophore's excited state to Glu-222. Loss of the Ser-205-Glu-222 hydrogen bond and isomerization of neutral Glu-222 explains the slow return to the equilibrium dark-adapted state of the chromophore. In the S65T structure, steric hindrance by the extra methyl group stabilizes a hydrogen bonding network, which prevents ionization of Glu-222. Therefore the fluorophore is permanently ionized, causing only a 489-nm excitation peak. This new understanding of proton redistribution in green fluorescent protein should enable engineering of environmentally sensitive fluorescent indicators and UV-triggered fluorescent markers of protein diffusion and trafficking in living cells.

  17. Homogeneous assay for biotin based on Aequorea victoria bioluminescence resonance energy transfer system.

    PubMed

    Gorokhovatsky, Andrey Yu; Rudenko, Natalia V; Marchenkov, Victor V; Skosyrev, Vitaly S; Arzhanov, Maxim A; Burkhardt, Nils; Zakharov, Mikhail V; Semisotnov, Gennady V; Vinokurov, Leonid M; Alakhov, Yuli B

    2003-02-01

    Here we describe a homogeneous assay for biotin based on bioluminescence resonance energy transfer (BRET) between aequorin and enhanced green fluorescent protein (EGFP). The fusions of aequorin with streptavidin (SAV) and EGFP with biotin carboxyl carrier protein (BCCP) were purified after expression of the corresponding genes in Escherichia coli cells. Association of SAV-aequorin and BCCP-EGFP fusions was followed by BRET between aequorin (donor) and EGFP (acceptor), resulting in significantly increasing 510 nm and decreasing 470 nm bioluminescence intensity. It was shown that free biotin inhibited BRET due to its competition with BCCP-EGFP for binding to SAV-aequorin. These properties were exploited to demonstrate competitive homogeneous BRET assay for biotin.

  18. Kinematics and Fluid Dynamics of Jellyfish Maneuvering

    NASA Astrophysics Data System (ADS)

    Miller, Laura; Hoover, Alex

    2014-11-01

    Jellyfish propel themselves through the water through periodic contractions of their elastic bells. Some jellyfish, such as the moon jellyfish Aurelia aurita and the upside down jellyfish Cassiopea xamachana, can perform turns via asymmetric contractions of the bell. The fluid dynamics of jellyfish forward propulsion and turning is explored here by analyzing the contraction kinematics of several species and using flow visualization to quantify the resulting flow fields. The asymmetric contraction and structure of the jellyfish generates asymmetries in the starting and stopping vortices. This creates a diagonal jet and a net torque acting on the jellyfish. Results are compared to immersed boundary simulations

  19. Immunostimulation effect of jellyfish collagen.

    PubMed

    Sugahara, Takuya; Ueno, Masashi; Goto, Yoko; Shiraishi, Ryusuke; Doi, Mikiharu; Akiyama, Koichi; Yamauchi, Satoshi

    2006-09-01

    Certain edible large jellyfishes belonging to the order Rhizostomeae are consumed in large quantities in China and Japan. The exumbrella part of the edible jellyfish Stomolophus nomurai was cut and soaked in dilute hydrochloric acid solution (pH 3.0) for 12 h, and heated at 121 degrees C for 20 min. The immunostimulation effects of the jellyfish extract were examined. The jellyfish extract enhanced IgM production of human hybridoma HB4C5 cells 34-fold. IgM and IgG production of human peripheral blood lymphocytes (PBL) were also accelerated, 2.8- and 1.4-fold respectively. Moreover, production of interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha by human PBL was stimulated 100- and 17-fold respectively. Collagenase treatment inactivated the immunostimulation activity of the jellyfish extract. In addition, purified collagen from bovine Achilles' tendon accelerated IgM production of hybridoma cells. These facts mean that collagen has an immunostimulation effect, and that the active substance in jellyfish extract is collagen.

  20. Radioactivity in three species of eastern Mediterranean jellyfish.

    PubMed

    Mamish, S; Al-Masri, M S; Durgham, H

    2015-11-01

    Activity concentrations of (137)Cs, (40)K, (210)Po, (210)Pb, (234)U and (238)U were determined in umbrella and oral arms of three widely distributed jellyfish species; namely Rhopilema nomadica Galil, 1990, Aurelia aurita Linne, 1758 and Aequorea forskalea Péron & Lesueur, 1810 collected from February 2011 to January 2012 in four sampling locations along the Syrian coast (Eastern Mediterranean Sea). The results have shown significant variations in radionuclides activity concentrations amongst the species. The average activity concentrations of (40)K, (210)Po, (210)Pb, (234)U and (238)U in the umbrella of R. nomadica species were higher than the average activity concentrations in the umbrella of A. aurita species by about 3.2, 1.4, 1.8, 3.2 and 3.2 folds, and A. forskalea species by about 45.5, 15.4, 19, 7.4 and 7.6 folds, respectively. The average activity concentrations of (40)K, (210)Po, (210)Pb, (234)U and (238)U in oral arms of R. nomadica species were higher than the average activity concentrations in oral arms of A. aurita species by about 3.8, 1.7, 1.9, 2.8 and 2.9 folds, respectively. (137)Cs activity concentrations were below the detection limit in all measured samples. In addition, activity concentrations of (137)Cs, (40)K, (210)Po, (210)Pb, (234)U and (238)U were also determined in 44 surface seawater samples and the activity concentrations ranged between 10.6 and 11.9 Bq l(-1) for (40)K, 1.1 and 1.4 mBq l(-1) for (210)Po, 0.5 and 0.7 mBq l(-1) for (210)Pb, 40.8 and 44.5 mBq l(-1) for (234)U, and 36.9 and 38.4 mBq l(-1) for (238)U, while (137)Cs activity concentrations were below the detection limit in all measured samples. Moreover, the umbrella and oral arms readily accumulated (40)K, (210)Po, (210)Pb, (234)U and (238)U above ambient seawater levels in the sequence of (210)Po > (210)Pb > (4) K > (234)U and (238)U. Concentration ratio (CR) values were relatively high for (210)Po and (210)Pb and reached 10(3) and 10(2), respectively for the jellyfish R

  1. Pain from bluebottle jellyfish stings.

    PubMed

    Li, Li; McGee, Richard G; Webster, Angela C

    2015-07-01

    An 11-year-old girl presented to the emergency department with severe pain after a jellyfish sting at a New South Wales beach. Bluebottle (Physalia) jellyfish was deemed the most likely cause considering her geographical location. The Australian Resuscitation Council Guideline (2010) suggests immersing in water as hot as can be tolerated for 20 min for treating pain from jellyfish stings. This guideline was written based on past case reports, books and randomised controlled trials (RCTs). We performed a search to assess the most current evidence for relief of pain from Bluebottle jellyfish stings, which yielded two systematic reviews and seven RCTs. Both systematic reviews had similar conclusions, with one of the RCTs used in both reviews showing the most relevance to our presenting patient in terms of demographics, location and jellyfish type. This journal club article is an appraisal of this RCT by Loten et al. and the validity of its conclusion that hot water immersion is most effective for the relief of pain from Bluebottle stings.

  2. [Jellyfish sting. A case report].

    PubMed

    Tamás, Ildikó; Veres, Imre; Remenyik, Eva

    2008-01-06

    Jellyfish bites in Hungary are rare. Yet, from a differential diagnostic point of view this epizoonozis might gain importance given the ever-growing popularity of seaside tourism. A 10 year old female patient was stung by a jellyfish while sea-bathing in the Adriatic in the summer of 2005. A couple of minutes after the bite urticaria were formed in the contacted area accompanied by a burning and sore sensation. In a few hours the above lesions turned livid and the patient developed low-grade fever and general discomfort. In acute therapy she received thorough rinse with vinegar, antibiotic ointment and systemic calcium. General symptoms regressed within 24 hours and dermatological symptoms improved progressively. Finally, the patient grew symptomless in 4 weeks altogether due to general antihistamine and local antibiotic therapy. 3 months later the patient presented again with hyperaemic papules and an increasing itching and burning sensation in the previously jellyfish-contacted area. Histopathology showed vascular involvement and eosinophilic infiltration. The inflammatory symptoms gradually diminished to locally applied steroids in an occlusive bandage leaving behind hypopigmentation. Although bare-skin contact with the different poisonous jellyfish species usually do lead to the forming of dermatological symptoms, vascular involvement developed months after the encounter in the exposure site has seldom been published. The article covers the main potential symptoms of jellyfish stings--both local and general--going into details about the possible dermatological differential diagnoses. Furthermore, the most venomous jellyfish species, their geographical habitats, do's and don't-s of first aid, therapy and prevention are being briefly discussed by the authors.

  3. Proton nuclear magnetic resonance and fluorescence spectroscopic studies of segmental mobility in aequorin and a green fluorescent protein from Aequorea forskalea

    SciTech Connect

    Nageswara Rao, B.D.; Kemple, M.D.; Prendergast, F.G.

    1980-10-01

    Aequorin is a protein of low molecular weight (20,000) isolated from the jellyfish Aequorea forskalea which emits blue light upon the binding of Ca/sup 2 +/ ions. This bioluminescence requires neither exogenous oxygen nor any other cofactors. The light emission occurs from an excited state of a chromophore (an imidazolopyrazinone) which is tightly and noncovalently bound to the protein. Apparently the binding of Ca/sup 2 +/ by the protein induces changes in the protein conformation which allow oxygen, already bound or otherwise held by the protein, to react with and therein oxidize the chromophore. The resulting discharged protein remains intact, with the Ca/sup 2 +/ and the chromophore still bound, but is incapable of further luminescence. The fluorescence spectrum of this discharged protein and the bioluminescence spectrum of the original charged aequorin are identical. A green fluorescent protein (GFP) of approx. 30,000 mol wt isolated from the same organism, functions in vivo as an acceptor of energy from aequorin and subsequently emits green light. We are applying proton nuclear magnetic resonance (NMR) spectroscopy and fluorescence spectroscopy to examine structural details of, and fluctuations associated with the luminescent reaction of aequorin and the in vivo energy transfer from aequorin to the GFP.

  4. Social behaviour in mesopelagic jellyfish.

    PubMed

    Kaartvedt, Stein; Ugland, Karl I; Klevjer, Thor A; Røstad, Anders; Titelman, Josefin; Solberg, Ingrid

    2015-06-11

    Gelatinous organisms apparently play a central role in deep pelagic ecosystems, but lack of observational methodologies has restricted information on their behaviour. We made acoustic records of diel migrating jellyfish Periphylla periphylla forming small, ephemeral groups at the upper fringe of an acoustic scattering layer consisting of krill. Groups of P. periphylla were also documented photographically using a remotely operated vehicle (ROV). Although the adaptive value of group formation remains speculative, we clearly demonstrate the ability of these jellyfishes to locate and team up with each other.

  5. Social behaviour in mesopelagic jellyfish

    PubMed Central

    Kaartvedt, Stein; Ugland, Karl I.; Klevjer, Thor A.; Røstad, Anders; Titelman, Josefin; Solberg, Ingrid

    2015-01-01

    Gelatinous organisms apparently play a central role in deep pelagic ecosystems, but lack of observational methodologies has restricted information on their behaviour. We made acoustic records of diel migrating jellyfish Periphylla periphylla forming small, ephemeral groups at the upper fringe of an acoustic scattering layer consisting of krill. Groups of P. periphylla were also documented photographically using a remotely operated vehicle (ROV). Although the adaptive value of group formation remains speculative, we clearly demonstrate the ability of these jellyfishes to locate and team up with each other. PMID:26065904

  6. Social behaviour in mesopelagic jellyfish

    NASA Astrophysics Data System (ADS)

    Kaartvedt, Stein; Ugland, Karl I.; Klevjer, Thor A.; Røstad, Anders; Titelman, Josefin; Solberg, Ingrid

    2015-06-01

    Gelatinous organisms apparently play a central role in deep pelagic ecosystems, but lack of observational methodologies has restricted information on their behaviour. We made acoustic records of diel migrating jellyfish Periphylla periphylla forming small, ephemeral groups at the upper fringe of an acoustic scattering layer consisting of krill. Groups of P. periphylla were also documented photographically using a remotely operated vehicle (ROV). Although the adaptive value of group formation remains speculative, we clearly demonstrate the ability of these jellyfishes to locate and team up with each other.

  7. Exploring the therapeutic potential of jellyfish venom.

    PubMed

    Daly, Norelle L; Seymour, Jamie; Wilson, David

    2014-10-01

    The venom of certain jellyfish has long been known to be potentially fatal to humans, but it is only recently that details of the proteomes of these fascinating creatures are emerging. The molecular contents of the nematocysts from several jellyfish species have now been analyzed using proteomic MS approaches and include the analysis of Chironex fleckeri, one of the most venomous jellyfish known. These studies suggest that some species contain toxins related to peptides and proteins found in other venomous creatures. The detailed characterization of jellyfish venom is likely to provide insight into the diversification of toxins and might be a valuable resource in drug design.

  8. Big Spherules near 'Victoria'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This frame from the microscopic imager on NASA's Mars Exploration Rover Opportunity shows spherules up to about 5 millimeters (one-fifth of an inch) in diameter. The camera took this image during the 924th Martian day, or sol, of Opportunity's Mars-surface mission (Aug. 30, 2006), when the rover was about 200 meters (650 feet) north of 'Victoria Crater.'

    Opportunity discovered spherules like these, nicknamed 'blueberries,' at its landing site in 'Eagle Crater,' and investigations determined them to be iron-rich concretions that formed inside deposits soaked with groundwater. However, such concretions were much smaller or absent at the ground surface along much of the rover's trek of more than 5 kilometers (3 miles) southward to Victoria. The big ones showed up again when Opportunity got to the ring, or annulus, of material excavated and thrown outward by the impact that created Victoria Crater. Researchers hypothesize that some layer beneath the surface in Victoria's vicinity was once soaked with water long enough to form the concretions, that the crater-forming impact dispersed some material from that layer, and that Opportunity might encounter that layer in place if the rover drives down into the crater.

  9. Marketing ACE in Victoria.

    ERIC Educational Resources Information Center

    2001

    This publication presents options raised through various forums for marketing adult and community education (ACE) in Victoria, Australia, and suggested strategies. After an introduction (chapter 1), chapters 2 and 3 provide a broad view of the current situation for marketing ACE. Chapter 2 discusses general issues in the current position--ACE…

  10. Dangerous jellyfish blooms are predictable

    PubMed Central

    Gershwin, Lisa-ann; Condie, Scott A.; Mansbridge, Jim V.; Richardson, Anthony J.

    2014-01-01

    The potentially fatal Irukandji syndrome is relatively common in tropical waters throughout the world. It is caused by the sting of the Irukandji jellyfish, a family of box jellyfish that are almost impossible to detect in the water owing to their small size and transparency. Using collated medical records of stings and local weather conditions, we show that the presence of Irukandji blooms in coastal waters can be forecast on the basis of wind conditions. On the Great Barrier Reef, blooms largely coincide with relaxation of the prevailing southeasterly trade winds, with average conditions corresponding to near zero alongshore wind on the day prior to the sting. These conditions are consistent with hypotheses long held by local communities and provide a basis for designing management interventions that have the potential to eliminate the majority of stings. PMID:24829278

  11. Jellyfish Stings: A Practical Approach.

    PubMed

    Lakkis, Najla A; Maalouf, Grace J; Mahmassani, Dina M

    2015-09-01

    Jellyfish have a worldwide distribution. Their stings can cause different reactions, ranging from cutaneous, localized, and self-limited to serious systemic or fatal ones, depending on the envenoming species. Several first aid treatments are used to manage such stings but few have evidence behind their use. This review of the literature describes and discusses the different related first aid and treatment recommendations, ending with a summarized practical approach. Further randomized controlled trials in this field are needed.

  12. Immunological and toxinological responses to jellyfish stings.

    PubMed

    Tibballs, James; Yanagihara, Angel A; Turner, Helen C; Winkel, Ken

    2011-10-01

    Just over a century ago, animal responses to injections of jellyfish extracts unveiled the phenomenon of anaphylaxis. Yet, until very recently, understanding of jellyfish sting toxicity has remained limited. Upon contact, jellyfish stinging cells discharge complex venoms, through thousands of barbed tubules, into the skin resulting in painful and, potentially, lethal envenomations. This review examines the immunological and toxinological responses to stings by prominent species of jellyfish including Physalia sp (Portuguese Man-o-War, Blue-bottle), Cubozoan jellyfish including Chironex fleckeri, several Carybdeids including Carybdea arborifera and Alatina moseri, Linuche unguiculta (Thimble jellyfish), a jellyfish responsible for Irukandji syndrome (Carukia barnesi) and Pelagia noctiluca. Jellyfish venoms are composed of potent proteinaceous porins (cellular membrane pore-forming toxins), neurotoxic peptides, bioactive lipids and other small molecules whilst the tubules contain ancient collagens and chitins. We postulate that immunologically, both tubular structural and functional biopolymers as well as venom components can initiate innate, adaptive, as well as immediate and delayed hypersensitivity reactions that may be amenable to topical anti-inflammatory-immunomodifier therapy. The current challenge for immunotoxinologists is to deconstruct the actions of venom components to target therapeutic modalities for sting treatment.

  13. Stretched View Showing 'Victoria'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Stretched View Showing 'Victoria'

    This pair of images from the panoramic camera on NASA's Mars Exploration Rover Opportunity served as initial confirmation that the two-year-old rover is within sight of 'Victoria Crater,' which it has been approaching for more than a year. Engineers on the rover team were unsure whether Opportunity would make it as far as Victoria, but scientists hoped for the chance to study such a large crater with their roving geologist. Victoria Crater is 800 meters (nearly half a mile) in diameter, about six times wider than 'Endurance Crater,' where Opportunity spent several months in 2004 examining rock layers affected by ancient water.

    When scientists using orbital data calculated that they should be able to detect Victoria's rim in rover images, they scrutinized frames taken in the direction of the crater by the panoramic camera. To positively characterize the subtle horizon profile of the crater and some of the features leading up to it, researchers created a vertically-stretched image (top) from a mosaic of regular frames from the panoramic camera (bottom), taken on Opportunity's 804th Martian day (April 29, 2006).

    The stretched image makes mild nearby dunes look like more threatening peaks, but that is only a result of the exaggerated vertical dimension. This vertical stretch technique was first applied to Viking Lander 2 panoramas by Philip Stooke, of the University of Western Ontario, Canada, to help locate the lander with respect to orbiter images. Vertically stretching the image allows features to be more readily identified by the Mars Exploration Rover science team.

    The bright white dot near the horizon to the right of center (barely visible without labeling or zoom-in) is thought to be a light-toned outcrop on the far wall of the crater, suggesting that the rover can see over the low rim of Victoria. In figure 1, the northeast and southeast rims are labeled

  14. The jellyfish buffet: jellyfish enhance seabird foraging opportunities by concentrating prey

    PubMed Central

    Sato, Nobuhiko N.; Kokubun, Nobuo; Yamamoto, Takashi; Watanuki, Yutaka; Kitaysky, Alexander S.; Takahashi, Akinori

    2015-01-01

    High levels of jellyfish biomass have been reported in marine ecosystems around the world, but understanding of their ecological role remains in its infancy. Jellyfish are generally thought to have indirect negative impacts on higher trophic-level predators, through changes in lower trophic pathways. However, high densities of jellyfish in the water column may affect the foraging behaviour of marine predators more directly, and the effects may not always be negative. Here, we present novel observations of a diving seabird, the thick-billed murre, feeding on fish aggregating among the long tentacles of large jellyfish, by using small video loggers attached to the birds. We show that the birds encountered large jellyfish, Chrysaora melanaster, during most of their dives, commonly fed on fish associated with jellyfish, and appeared to specifically target jellyfish with a high number of fish aggregating in their tentacles, suggesting the use of jellyfish may provide significant energetic benefits to foraging murres. We conclude that jellyfish provide feeding opportunities for diving seabirds by concentrating forage fish, and that the impacts of jellyfish on marine ecosystems are more complex than previously anticipated and may be beneficial to seabirds. PMID:26311157

  15. The jellyfish buffet: jellyfish enhance seabird foraging opportunities by concentrating prey.

    PubMed

    Sato, Nobuhiko N; Kokubun, Nobuo; Yamamoto, Takashi; Watanuki, Yutaka; Kitaysky, Alexander S; Takahashi, Akinori

    2015-08-01

    High levels of jellyfish biomass have been reported in marine ecosystems around the world, but understanding of their ecological role remains in its infancy. Jellyfish are generally thought to have indirect negative impacts on higher trophic-level predators, through changes in lower trophic pathways. However, high densities of jellyfish in the water column may affect the foraging behaviour of marine predators more directly, and the effects may not always be negative. Here, we present novel observations of a diving seabird, the thick-billed murre, feeding on fish aggregating among the long tentacles of large jellyfish, by using small video loggers attached to the birds. We show that the birds encountered large jellyfish, Chrysaora melanaster, during most of their dives, commonly fed on fish associated with jellyfish, and appeared to specifically target jellyfish with a high number of fish aggregating in their tentacles, suggesting the use of jellyfish may provide significant energetic benefits to foraging murres. We conclude that jellyfish provide feeding opportunities for diving seabirds by concentrating forage fish, and that the impacts of jellyfish on marine ecosystems are more complex than previously anticipated and may be beneficial to seabirds.

  16. Jellyfish Modulate Bacterial Dynamic and Community Structure

    PubMed Central

    Tinta, Tinkara; Kogovšek, Tjaša; Malej, Alenka; Turk, Valentina

    2012-01-01

    Jellyfish blooms have increased in coastal areas around the world and the outbreaks have become longer and more frequent over the past few decades. The Mediterranean Sea is among the heavily affected regions and the common bloom - forming taxa are scyphozoans Aurelia aurita s.l., Pelagia noctiluca, and Rhizostoma pulmo. Jellyfish have few natural predators, therefore their carcasses at the termination of a bloom represent an organic-rich substrate that supports rapid bacterial growth, and may have a large impact on the surrounding environment. The focus of this study was to explore whether jellyfish substrate have an impact on bacterial community phylotype selection. We conducted in situ jellyfish - enrichment experiment with three different jellyfish species. Bacterial dynamic together with nutrients were monitored to assess decaying jellyfish-bacteria dynamics. Our results show that jellyfish biomass is characterized by protein rich organic matter, which is highly bioavailable to ‘jellyfish - associated’ and ‘free - living’ bacteria, and triggers rapid shifts in bacterial population dynamics and composition. Based on 16S rRNA clone libraries and denaturing gradient gel electrophoresis (DGGE) analysis, we observed a rapid shift in community composition from unculturable Alphaproteobacteria to culturable species of Gammaproteobacteria and Flavobacteria. The results of sequence analyses of bacterial isolates and of total bacterial community determined by culture independent genetic analysis showed the dominance of the Pseudoalteromonadaceae and the Vibrionaceae families. Elevated levels of dissolved proteins, dissolved organic and inorganic nutrient release, bacterial abundance and carbon production as well as ammonium concentrations characterized the degradation process. The biochemical composition of jellyfish species may influence changes in the amount of accumulated dissolved organic and inorganic nutrients. Our results can contribute insights into

  17. Jellyfish modulate bacterial dynamic and community structure.

    PubMed

    Tinta, Tinkara; Kogovšek, Tjaša; Malej, Alenka; Turk, Valentina

    2012-01-01

    Jellyfish blooms have increased in coastal areas around the world and the outbreaks have become longer and more frequent over the past few decades. The Mediterranean Sea is among the heavily affected regions and the common bloom-forming taxa are scyphozoans Aurelia aurita s.l., Pelagia noctiluca, and Rhizostoma pulmo. Jellyfish have few natural predators, therefore their carcasses at the termination of a bloom represent an organic-rich substrate that supports rapid bacterial growth, and may have a large impact on the surrounding environment. The focus of this study was to explore whether jellyfish substrate have an impact on bacterial community phylotype selection. We conducted in situ jellyfish-enrichment experiment with three different jellyfish species. Bacterial dynamic together with nutrients were monitored to assess decaying jellyfish-bacteria dynamics. Our results show that jellyfish biomass is characterized by protein rich organic matter, which is highly bioavailable to 'jellyfish-associated' and 'free-living' bacteria, and triggers rapid shifts in bacterial population dynamics and composition. Based on 16S rRNA clone libraries and denaturing gradient gel electrophoresis (DGGE) analysis, we observed a rapid shift in community composition from unculturable Alphaproteobacteria to culturable species of Gammaproteobacteria and Flavobacteria. The results of sequence analyses of bacterial isolates and of total bacterial community determined by culture independent genetic analysis showed the dominance of the Pseudoalteromonadaceae and the Vibrionaceae families. Elevated levels of dissolved proteins, dissolved organic and inorganic nutrient release, bacterial abundance and carbon production as well as ammonium concentrations characterized the degradation process. The biochemical composition of jellyfish species may influence changes in the amount of accumulated dissolved organic and inorganic nutrients. Our results can contribute insights into possible changes in

  18. Micro- and macrorheology of jellyfish extracellular matrix.

    PubMed

    Gambini, Camille; Abou, Bérengère; Ponton, Alain; Cornelissen, Annemiek J M

    2012-01-04

    Mechanical properties of the extracellular matrix (ECM) play a key role in tissue organization and morphogenesis. Rheological properties of jellyfish ECM (mesoglea) were measured in vivo at the cellular scale by passive microrheology techniques: microbeads were injected in jellyfish ECM and their Brownian motion was recorded to determine the mechanical properties of the surrounding medium. Microrheology results were compared with macrorheological measurements performed with a shear rheometer on slices of jellyfish mesoglea. We found that the ECM behaved as a viscoelastic gel at the macroscopic scale and as a much softer and heterogeneous viscoelastic structure at the microscopic scale. The fibrous architecture of the mesoglea, as observed by differential interference contrast and scanning electron microscopy, was in accord with these scale-dependent mechanical properties. Furthermore, the evolution of the mechanical properties of the ECM during aging was investigated by measuring microrheological properties at different jellyfish sizes. We measured that the ECM in adult jellyfish was locally stiffer than in juvenile ones. We argue that this stiffening is a consequence of local aggregations of fibers occurring gradually during aging of the jellyfish mesoglea and is enhanced by repetitive muscular contractions of the jellyfish.

  19. Monitoring transgenic plants using in vivo markers

    SciTech Connect

    Stewart, C.N. Jr.

    1996-06-01

    The gene coding for green fluorecent protein (GFP), isolated and cloned from the jellyfish Aequorea victoria, is an ideal transgene for the monitoring of any plant species. It has the ability to fluoresce without added substrate, enzyme, or cofactor; it does not introduce morphological or sexual aberrations when expressed. 7 refs., 1 fig.

  20. Exceptionally preserved jellyfishes from the Middle Cambrian.

    PubMed

    Cartwright, Paulyn; Halgedahl, Susan L; Hendricks, Jonathan R; Jarrard, Richard D; Marques, Antonio C; Collins, Allen G; Lieberman, Bruce S

    2007-10-31

    Cnidarians represent an early diverging animal group and thus insight into their origin and diversification is key to understanding metazoan evolution. Further, cnidarian jellyfish comprise an important component of modern marine planktonic ecosystems. Here we report on exceptionally preserved cnidarian jellyfish fossils from the Middle Cambrian (approximately 505 million years old) Marjum Formation of Utah. These are the first described Cambrian jellyfish fossils to display exquisite preservation of soft part anatomy including detailed features of structures interpreted as trailing tentacles and subumbrellar and exumbrellar surfaces. If the interpretation of these preserved characters is correct, their presence is diagnostic of modern jellyfish taxa. These new discoveries may provide insight into the scope of cnidarian diversity shortly after the Cambrian radiation, and would reinforce the notion that important taxonomic components of the modern planktonic realm were in place by the Cambrian period.

  1. Simulation of Piezoelectric Jellyfish Power Generator

    NASA Astrophysics Data System (ADS)

    Wu, Yeong-Jen; Lai, Wei-Hsiang

    The energy problem is getting increasingly serious. As such, unused energy recovery technology is crucial for environmental protection, which has been investigated extensively. Several methods have been developed to utilize scavenged energy from the environment, such as waste heat, solar energy, wind energy, and tides energy to convert into useful power. There is a new idea of piezoelectric jellyfish generator which combines the utilization of sea wave and vibration energy. When sea wave passes through the jellyfish, the wave causes the tentacles to vibrate. The tentacles is made of piezoelectric polymer which can convert the strain energy into electrical energy. This paper discusses about the piezoelectric jellyfish's tentacles being disturbed by wave in the sea. We employed the commercial CFD software CFD-ACE+ 2006 to simulate this phenomenon. The parameters including its tentacle length (L) and wave propagating function (Y) are studied which affect the piezoelectric jellyfish capacity to generate power.

  2. Optimal hash arrangement of tentacles in jellyfish

    PubMed Central

    Okabe, Takuya; Yoshimura, Jin

    2016-01-01

    At first glance, the trailing tentacles of a jellyfish appear to be randomly arranged. However, close examination of medusae has revealed that the arrangement and developmental order of the tentacles obey a mathematical rule. Here, we show that medusa jellyfish adopt the best strategy to achieve the most uniform distribution of a variable number of tentacles. The observed order of tentacles is a real-world example of an optimal hashing algorithm known as Fibonacci hashing in computer science. PMID:27273762

  3. Optimal hash arrangement of tentacles in jellyfish

    NASA Astrophysics Data System (ADS)

    Okabe, Takuya; Yoshimura, Jin

    2016-06-01

    At first glance, the trailing tentacles of a jellyfish appear to be randomly arranged. However, close examination of medusae has revealed that the arrangement and developmental order of the tentacles obey a mathematical rule. Here, we show that medusa jellyfish adopt the best strategy to achieve the most uniform distribution of a variable number of tentacles. The observed order of tentacles is a real-world example of an optimal hashing algorithm known as Fibonacci hashing in computer science.

  4. Length Is Associated with Pain: Jellyfish with Painful Sting Have Longer Nematocyst Tubules than Harmless Jellyfish.

    PubMed

    Kitatani, Ryuju; Yamada, Mayu; Kamio, Michiya; Nagai, Hiroshi

    2015-01-01

    A large number of humans are stung by jellyfish all over the world. The stings cause acute pain followed by persistent pain and local inflammation. Harmful jellyfish species typically cause strong pain, whereas harmless jellyfish cause subtle or no pain. Jellyfish sting humans by injecting a tubule, contained in the nematocyst, the stinging organ of jellyfish. The tubule penetrates into the skin leading to venom injection. The detailed morphology of the nematocyst tubule and molecular structure of the venom in the nematocyst has been reported; however, the mechanism responsible for the difference in pain that is caused by harmful and harmless jellyfish sting has not yet been explored or explained. Therefore, we hypothesized that differences in the length of the nematocyst tubule leads to different degrees of epithelial damage. The initial acute pain might be generated by penetration of the tubule, which stimulates pain receptor neurons, whilst persistent pain might be caused by injection of venom into the epithelium. To test this hypothesis we compared the lengths of discharged nematocyst tubules from harmful and harmless jellyfish species and evaluated their ability to penetrate human skin. The results showed that the harmful jellyfish species, Chrysaora pacifica, Carybdea brevipedalia, and Chironex yamaguchii, causing moderate to severe pain, have nematocyst tubules longer than 200 μm, compared with a jellyfish species that cause little or no pain, Aurelia aurita. The majority of the tubules of harmful jellyfishes, C. yamaguchii and C. brevipedalia, were sufficiently long to penetrate the human epidermis and physically stimulate the free nerve endings of Aδ pain receptor fibers around plexuses to cause acute pain and inject the venom into the human skin epithelium to cause persistent pain and inflammation.

  5. Length Is Associated with Pain: Jellyfish with Painful Sting Have Longer Nematocyst Tubules than Harmless Jellyfish

    PubMed Central

    Kitatani, Ryuju; Yamada, Mayu; Kamio, Michiya; Nagai, Hiroshi

    2015-01-01

    A large number of humans are stung by jellyfish all over the world. The stings cause acute pain followed by persistent pain and local inflammation. Harmful jellyfish species typically cause strong pain, whereas harmless jellyfish cause subtle or no pain. Jellyfish sting humans by injecting a tubule, contained in the nematocyst, the stinging organ of jellyfish. The tubule penetrates into the skin leading to venom injection. The detailed morphology of the nematocyst tubule and molecular structure of the venom in the nematocyst has been reported; however, the mechanism responsible for the difference in pain that is caused by harmful and harmless jellyfish sting has not yet been explored or explained. Therefore, we hypothesized that differences in the length of the nematocyst tubule leads to different degrees of epithelial damage. The initial acute pain might be generated by penetration of the tubule, which stimulates pain receptor neurons, whilst persistent pain might be caused by injection of venom into the epithelium. To test this hypothesis we compared the lengths of discharged nematocyst tubules from harmful and harmless jellyfish species and evaluated their ability to penetrate human skin. The results showed that the harmful jellyfish species, Chrysaora pacifica, Carybdea brevipedalia, and Chironex yamaguchii, causing moderate to severe pain, have nematocyst tubules longer than 200 μm, compared with a jellyfish species that cause little or no pain, Aurelia aurita. The majority of the tubules of harmful jellyfishes, C. yamaguchii and C. brevipedalia, were sufficiently long to penetrate the human epidermis and physically stimulate the free nerve endings of Aδ pain receptor fibers around plexuses to cause acute pain and inject the venom into the human skin epithelium to cause persistent pain and inflammation. PMID:26309256

  6. Ocean acidification alters fish-jellyfish symbiosis.

    PubMed

    Nagelkerken, Ivan; Pitt, Kylie A; Rutte, Melchior D; Geertsma, Robbert C

    2016-06-29

    Symbiotic relationships are common in nature, and are important for individual fitness and sustaining species populations. Global change is rapidly altering environmental conditions, but, with the exception of coral-microalgae interactions, we know little of how this will affect symbiotic relationships. We here test how the effects of ocean acidification, from rising anthropogenic CO2 emissions, may alter symbiotic interactions between juvenile fish and their jellyfish hosts. Fishes treated with elevated seawater CO2 concentrations, as forecast for the end of the century on a business-as-usual greenhouse gas emission scenario, were negatively affected in their behaviour. The total time that fish (yellowtail scad) spent close to their jellyfish host in a choice arena where they could see and smell their host was approximately three times shorter under future compared with ambient CO2 conditions. Likewise, the mean number of attempts to associate with jellyfish was almost three times lower in CO2-treated compared with control fish, while only 63% (high CO2) versus 86% (control) of all individuals tested initiated an association at all. By contrast, none of three fish species tested were attracted solely to jellyfish olfactory cues under present-day CO2 conditions, suggesting that the altered fish-jellyfish association is not driven by negative effects of ocean acidification on olfaction. Because shelter is not widely available in the open water column and larvae of many (and often commercially important) pelagic species associate with jellyfish for protection against predators, modification of the fish-jellyfish symbiosis might lead to higher mortality and alter species population dynamics, and potentially have flow-on effects for their fisheries.

  7. [The epilepsy of Guadalupe Victoria].

    PubMed

    Soto-Pérez-de-Celis, Enrique

    2008-01-01

    Guadalupe Victoria, the first President of Mexico, passed away in 1843 uictim of an ailment that, at the time, was diagnosed as epilepsy. The clinical data and the pathologic findings, however, suggest the possibility that Victoria had an underlying disease that was responsible for the seizures that affected him. In this article I propose that Guadalupe Victoria had in fact Chagas Disease, and that he was infected with this parasitic malady while he lived in the tropical jungles of Veracruz, in eastern Mexico. Even though there aren't many published works regarding seizures secondary to chronic Chagas Disease, there are good descriptions of epileptic syndromes in patients with this infection. At the same time, the cardiac findings in Victoria's autopsy support the idea that he had some kind of cardiac pathology; in this case Chagasic dilated cardiomyopathy, which ultimately led to his death.

  8. pH-dependent fluorescence of a heterologously expressed Aequorea green fluorescent protein mutant: in situ spectral characteristics and applicability to intracellular pH estimation.

    PubMed

    Robey, R B; Ruiz, O; Santos, A V; Ma, J; Kear, F; Wang, L J; Li, C J; Bernardo, A A; Arruda, J A

    1998-07-14

    The green fluorescent protein of Aequorea victoria (GFP) is a natural peptide chromophore without substrate or cofactor requirements for fluorescence. In vitro, a recombinant F64L/S65T GFP mutant (GFPmut1) exhibited pH sensitive fluorescence within the physiologic range. When heterologously expressed in BS-C-1 cells or rabbit proximal tubule cells, uniform cytosolic and nuclear fluorescence was observed. Cytosolic fluorescence constituted over 80% of the total. Excitation scanning of transfected cells revealed two GFPmut1-specific regions that were pH-sensitive over the physiologic range, and each region exhibited a unique pH "bias" in fluorescence emission. Excitation at or near the expected maximum of 488 nm (region II) uniformly resulted in fluorescence that was preferentially altered at acidic pH. In contrast, a novel "wild-type" excitation peak at 400 nm (region I) resulted in alkaline-biased fluorescence similar to that described for the wild-type chromophore in vitro, suggesting that wild-type spectral features disrupted in vitro by mutagenesis may be recovered in intact cells. Calibration of intracellular pH (pHi) with in situ fluorescence following excitation in either region revealed a semilogarithmic relationship between fluorescence intensity and pH within the physiologic range. We therefore measured pHi changes attributable to altered Na/HCO3 cotransport (NBC) activity both in GFPmut1-expressing cells and in paired untransfected cells loaded with BCECF. Basal NBC activity was the same in each group, as was the stimulation of activity by 10% CO2, thus validating the utility of GFPmut1 as a fluorescent probe for pHi and establishing a novel, useful, and practical application for GFPmut1 in monitoring pHi in real time.

  9. Recurrent jellyfish blooms are a consequence of global oscillations

    PubMed Central

    Condon, Robert H.; Duarte, Carlos M.; Pitt, Kylie A.; Robinson, Kelly L.; Lucas, Cathy H.; Sutherland, Kelly R.; Mianzan, Hermes W.; Bogeberg, Molly; Purcell, Jennifer E.; Decker, Mary Beth; Uye, Shin-ichi; Madin, Laurence P.; Brodeur, Richard D.; Haddock, Steven H. D.; Malej, Alenka; Parry, Gregory D.; Eriksen, Elena; Quiñones, Javier; Acha, Marcelo; Harvey, Michel; Arthur, James M.; Graham, William M.

    2013-01-01

    A perceived recent increase in global jellyfish abundance has been portrayed as a symptom of degraded oceans. This perception is based primarily on a few case studies and anecdotal evidence, but a formal analysis of global temporal trends in jellyfish populations has been missing. Here, we analyze all available long-term datasets on changes in jellyfish abundance across multiple coastal stations, using linear and logistic mixed models and effect-size analysis to show that there is no robust evidence for a global increase in jellyfish. Although there has been a small linear increase in jellyfish since the 1970s, this trend was unsubstantiated by effect-size analysis that showed no difference in the proportion of increasing vs. decreasing jellyfish populations over all time periods examined. Rather, the strongest nonrandom trend indicated jellyfish populations undergo larger, worldwide oscillations with an approximate 20-y periodicity, including a rising phase during the 1990s that contributed to the perception of a global increase in jellyfish abundance. Sustained monitoring is required over the next decade to elucidate with statistical confidence whether the weak increasing linear trend in jellyfish after 1970 is an actual shift in the baseline or part of an oscillation. Irrespective of the nature of increase, given the potential damage posed by jellyfish blooms to fisheries, tourism, and other human industries, our findings foretell recurrent phases of rise and fall in jellyfish populations that society should be prepared to face. PMID:23277544

  10. Recurrent jellyfish blooms are a consequence of global oscillations.

    PubMed

    Condon, Robert H; Duarte, Carlos M; Pitt, Kylie A; Robinson, Kelly L; Lucas, Cathy H; Sutherland, Kelly R; Mianzan, Hermes W; Bogeberg, Molly; Purcell, Jennifer E; Decker, Mary Beth; Uye, Shin-ichi; Madin, Laurence P; Brodeur, Richard D; Haddock, Steven H D; Malej, Alenka; Parry, Gregory D; Eriksen, Elena; Quiñones, Javier; Acha, Marcelo; Harvey, Michel; Arthur, James M; Graham, William M

    2013-01-15

    A perceived recent increase in global jellyfish abundance has been portrayed as a symptom of degraded oceans. This perception is based primarily on a few case studies and anecdotal evidence, but a formal analysis of global temporal trends in jellyfish populations has been missing. Here, we analyze all available long-term datasets on changes in jellyfish abundance across multiple coastal stations, using linear and logistic mixed models and effect-size analysis to show that there is no robust evidence for a global increase in jellyfish. Although there has been a small linear increase in jellyfish since the 1970s, this trend was unsubstantiated by effect-size analysis that showed no difference in the proportion of increasing vs. decreasing jellyfish populations over all time periods examined. Rather, the strongest nonrandom trend indicated jellyfish populations undergo larger, worldwide oscillations with an approximate 20-y periodicity, including a rising phase during the 1990s that contributed to the perception of a global increase in jellyfish abundance. Sustained monitoring is required over the next decade to elucidate with statistical confidence whether the weak increasing linear trend in jellyfish after 1970 is an actual shift in the baseline or part of an oscillation. Irrespective of the nature of increase, given the potential damage posed by jellyfish blooms to fisheries, tourism, and other human industries, our findings foretell recurrent phases of rise and fall in jellyfish populations that society should be prepared to face.

  11. Jellyfish Body Plans Provide Allometric Advantages beyond Low Carbon Content

    PubMed Central

    Pitt, Kylie A.; Duarte, Carlos M.; Lucas, Cathy H.; Sutherland, Kelly R.; Condon, Robert H.; Mianzan, Hermes; Purcell, Jennifer E.; Robinson, Kelly L.; Uye, Shin-Ichi

    2013-01-01

    Jellyfish form spectacular blooms throughout the world’s oceans. Jellyfish body plans are characterised by high water and low carbon contents which enables them to grow much larger than non-gelatinous animals of equivalent carbon content and to deviate from non-gelatinous pelagic animals when incorporated into allometric relationships. Jellyfish have, however, been argued to conform to allometric relationships when carbon content is used as the metric for comparison. Here we test the hypothesis that differences in allometric relationships for several key functional parameters remain for jellyfish even after their body sizes are scaled to their carbon content. Data on carbon and nitrogen contents, rates of respiration, excretion, growth, longevity and swimming velocity of jellyfish and other pelagic animals were assembled. Allometric relationships between each variable and the equivalent spherical diameters of jellyfish and other pelagic animals were compared before and after sizes of jellyfish were standardised for their carbon content. Before standardisation, the slopes of the allometric relationships for respiration, excretion and growth were the same for jellyfish and other pelagic taxa but the intercepts differed. After standardisation, slopes and intercepts for respiration were similar but excretion rates of jellyfish were 10× slower, and growth rates 2× faster than those of other pelagic animals. Longevity of jellyfish was independent of size. The slope of the allometric relationship of swimming velocity of jellyfish differed from that of other pelagic animals but because they are larger jellyfish operate at Reynolds numbers approximately 10× greater than those of other pelagic animals of comparable carbon content. We conclude that low carbon and high water contents alone do not explain the differences in the intercepts or slopes of the allometric relationships of jellyfish and other pelagic animals and that the evolutionary longevity of jellyfish and

  12. Jellyfish body plans provide allometric advantages beyond low carbon content.

    PubMed

    Pitt, Kylie A; Duarte, Carlos M; Lucas, Cathy H; Sutherland, Kelly R; Condon, Robert H; Mianzan, Hermes; Purcell, Jennifer E; Robinson, Kelly L; Uye, Shin-Ichi

    2013-01-01

    Jellyfish form spectacular blooms throughout the world's oceans. Jellyfish body plans are characterised by high water and low carbon contents which enables them to grow much larger than non-gelatinous animals of equivalent carbon content and to deviate from non-gelatinous pelagic animals when incorporated into allometric relationships. Jellyfish have, however, been argued to conform to allometric relationships when carbon content is used as the metric for comparison. Here we test the hypothesis that differences in allometric relationships for several key functional parameters remain for jellyfish even after their body sizes are scaled to their carbon content. Data on carbon and nitrogen contents, rates of respiration, excretion, growth, longevity and swimming velocity of jellyfish and other pelagic animals were assembled. Allometric relationships between each variable and the equivalent spherical diameters of jellyfish and other pelagic animals were compared before and after sizes of jellyfish were standardised for their carbon content. Before standardisation, the slopes of the allometric relationships for respiration, excretion and growth were the same for jellyfish and other pelagic taxa but the intercepts differed. After standardisation, slopes and intercepts for respiration were similar but excretion rates of jellyfish were 10× slower, and growth rates 2× faster than those of other pelagic animals. Longevity of jellyfish was independent of size. The slope of the allometric relationship of swimming velocity of jellyfish differed from that of other pelagic animals but because they are larger jellyfish operate at Reynolds numbers approximately 10× greater than those of other pelagic animals of comparable carbon content. We conclude that low carbon and high water contents alone do not explain the differences in the intercepts or slopes of the allometric relationships of jellyfish and other pelagic animals and that the evolutionary longevity of jellyfish and

  13. 33 CFR 165.837 - Safety Zone; Invista Inc Facility Docks, Victoria Barge Canal, Victoria, Texas.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone; Invista Inc Facility Docks, Victoria Barge Canal, Victoria, Texas. 165.837 Section 165.837 Navigation and Navigable Waters... Guard District § 165.837 Safety Zone; Invista Inc Facility Docks, Victoria Barge Canal, Victoria,...

  14. Thermal effect on Aequorea green fluorescent protein anionic and neutral chromophore forms fluorescence.

    PubMed

    dos Santos, Andrea Martins

    2012-01-01

    The emission behaviour of Aequorea green fluorescent protein (A-GFP) chromophore, in both neutral (N) and anionic (A) form, was studied in the temperature range from 20 °C to 75 °C and at pH = 7. Excitation wavelengths of 399 nm and 476 nm were applied to probe the N and A forms environment, respectively. Both forms exhibit distinct fluorescence patterns at high temperature values. The emission quenching rate, following a temperature increase, is higher for the chromophore N form as a result of the hydrogen bond network weakening. The chromophore anionic form emission maximum is red shifted, upon temperature increase, due to a charge transfer process occurring after A form excitation.

  15. [Causes of jellyfish blooms and their influence on marine environment].

    PubMed

    Qu, Chang-feng; Song, Jin-ming; Li, Ning

    2014-12-01

    Jellyfish blooms have damaged the normal composition and function of marine ecosystem and ecological environments, which have been one of the new marine ecological disasters. In this study, we summarized the possible inducements of jellyfish blooms, and the influences of jellyfish blooms on biogenic elements, dissolved oxygen, seawater acidity and biological community were discussed emphatically. The results showed that jellyfish blooms had a close contact with its physiological structure and life history, which had favorable characteristics including simple body struc- ture, rapid growth, thriving reproduction and short generation interval to tolerate harsh environment better. Jellyfish abundance increased rapidly when it encountered suitable conditions. The temperature variations of seawater might be the major inducing factor which could result in jellyfish blooms. Jellyfish blooms may benefit from warmer temperature that could increase the food availability of jellyfish and promote jellyfish reproduction, especially for warm temperate jellyfish species. Eutrophication, climate change, overfishing, alien invasions and habitat modification were all possible important contributory factors of jellyfish blooms. Jellyfish could significantly influence the form distribution and biogeochemical cycling of biogenic elements. Jellyfish excreted NH4+ and P04(3-) at a rate of 59.1-91.5 micromol N x kg(-1) x h(-1) and 1.1-1.8 micromol P x kg(-1) x h(-1), which could meet about 8%-10% and 21.6% of the phytoplankton primary production requirement of N and P, respectively. Live jellyfish released dissolved organic carbon (DOC) at a rate of 1.0 micromol C x g(-1) x d(-1). As jellyfish decomposing, the effluxes of total N and total P were 4000 micromol N x kg(-1) x d(-1) and 120 micromol P x kg(-1) x d(-1), respectively, while the efflux of DOC reached 30 micromol C x g(-1) x d(-1). Jellyfish decomposition could cause seawater acidification and lowered level of dissolved oxygen

  16. Digital ischaemia: a rare but severe complication of jellyfish sting.

    PubMed

    Lam, Stacey C; Hung, Y W; Chow, Esther C S; Wong, Clara W Y; Tse, W L; Ho, P C

    2014-10-01

    We report a case of digital ischaemia in a 31-year-old man who presented with sudden hand numbness, swelling, and cyanosis 4 days after a jellyfish sting. This is a rare complication of jellyfish sting, characterised by a delayed but rapid downhill course. Despite serial monitoring with prompt fasciotomy and repeated debridement, he developed progressive ischaemia in multiple digits with gangrenous change. He subsequently underwent major reconstructive surgery and aggressive rehabilitation. Although jellyfish stings are not uncommon, no severe jellyfish envenomation has been reported in the past in Hong Kong and there has not been any consensus on the management of such injuries. This is the first local case report of jellyfish sting leading to serious hand complications. This case revealed that patients who sustain a jellyfish sting deserve particular attention to facilitate early detection of complications and implementation of therapy.

  17. Hypertonic saline in the treatment of corneal jellyfish stings.

    PubMed

    Yu Yao, Hsin; Cho, Ta Hsiung; Lu, Ching Hsiang; Lin, Feng Chi; Horng, Chi Ting

    2016-02-01

    A 20-year-old male soldier was hit by the jellyfish. The ophthalmic examination revealed that epithelial keratitis and corneal oedema in the right eye. We prescribed 3% NaCl eyedrops and 0.3% Norfloxacin eyedrops in the treatment of the corneal jellyfish stings. Two weeks later, the cornea in the right eye healed. In this case report, 3% NaCl eyedrops was effective in the treatment of acute phase of jellyfish stings of the cornea.

  18. Study on the carry capacity of edible jellyfish fishery in Liaodong Bay

    NASA Astrophysics Data System (ADS)

    You, Kui; Bian, Yongning; Ma, Caihua; Chi, Xupeng; Liu, Zhiqiang; Zhang, Yuyu

    2016-06-01

    Jellyfish fishing is a special type of fishery that mainly exists in some countries of East and Southeast Asia. China has the largest jellyfish fishery yield in the world with an annual harvest of around 300 thousand tons. Liaodong Bay is the most important jellyfish fishery ground in China. However, due to the high benefits of jellyfish fishery, which leads to illegal and out-of-season jellyfish fishing occurring each year in Liaodong Bay. Illegal jellyfish fishery in Liaodong Bay is a typical example of the tragedy of the commons. The key problem is that fishermen seek to an illegally initiate jellyfish fishing as early as possible. In this paper, basing on the data of edible jellyfish's biology and ecology, we mainly analyzed the history of jellyfish fishery in China, especially in Liaodong bay, and then we calculated the carry capacity of edible jellyfish in Liaodong Bay which is about 300 thousand tons one year. This number is equal to the recent annual yield of edible jellyfish in China. Furthermore, basing on the carry capacity and reasonable quotas price analysis, we set up a Jellyfish fishing quotas and deficit quotas buyback system which could be a suitable and effective solution for jellyfish fishery management and development in Liaodong Bay at the underlying roots. Although China is the first country with edible jellyfish aquaculture, the annual yield of jellyfish aquaculture is only one fifth of jellyfish fishing. So, there is a very bright developing prospect about edible jellyfish aquaculture in China.

  19. Jellyfish collagen scaffolds for cartilage tissue engineering.

    PubMed

    Hoyer, Birgit; Bernhardt, Anne; Lode, Anja; Heinemann, Sascha; Sewing, Judith; Klinger, Matthias; Notbohm, Holger; Gelinsky, Michael

    2014-02-01

    Porous scaffolds were engineered from refibrillized collagen of the jellyfish Rhopilema esculentum for potential application in cartilage regeneration. The influence of collagen concentration, salinity and temperature on fibril formation was evaluated by turbidity measurements and quantification of fibrillized collagen. The formation of collagen fibrils with a typical banding pattern was confirmed by atomic force microscopy and transmission electron microscopy analysis. Porous scaffolds from jellyfish collagen, refibrillized under optimized conditions, were fabricated by freeze-drying and subsequent chemical cross-linking. Scaffolds possessed an open porosity of 98.2%. The samples were stable under cyclic compression and displayed an elastic behavior. Cytotoxicity tests with human mesenchymal stem cells (hMSCs) did not reveal any cytotoxic effects of the material. Chondrogenic markers SOX9, collagen II and aggrecan were upregulated in direct cultures of hMSCs upon chondrogenic stimulation. The formation of typical extracellular matrix components was further confirmed by quantification of sulfated glycosaminoglycans.

  20. Not all jellyfish are equal: isotopic evidence for inter- and intraspecific variation in jellyfish trophic ecology

    PubMed Central

    Fleming, Nicholas E.C.; Newton, Jason; Houghton, Jonathan D.R.

    2015-01-01

    Jellyfish are highly topical within studies of pelagic food-webs and there is a growing realisation that their role is more complex than once thought. Efforts being made to include jellyfish within fisheries and ecosystem models are an important step forward, but our present understanding of their underlying trophic ecology can lead to their oversimplification in these models. Gelatinous zooplankton represent a polyphyletic assemblage spanning >2,000 species that inhabit coastal seas to the deep-ocean and employ a wide variety of foraging strategies. Despite this diversity, many contemporary modelling approaches include jellyfish as a single functional group feeding at one or two trophic levels at most. Recent reviews have drawn attention to this issue and highlighted the need for improved communication between biologists and theoreticians if this problem is to be overcome. We used stable isotopes to investigate the trophic ecology of three co-occurring scyphozoan jellyfish species (Aurelia aurita, Cyanea lamarckii and C. capillata) within a temperate, coastal food-web in the NE Atlantic. Using information on individual size, time of year and δ13C and δ15N stable isotope values, we examined: (1) whether all jellyfish could be considered as a single functional group, or showed distinct inter-specific differences in trophic ecology; (2) Were size-based shifts in trophic position, found previously in A. aurita, a common trait across species?; (3) When considered collectively, did the trophic position of three sympatric species remain constant over time? Differences in δ15N (trophic position) were evident between all three species, with size-based and temporal shifts in δ15N apparent in A. aurita and C. capillata. The isotopic niche width for all species combined increased throughout the season, reflecting temporal shifts in trophic position and seasonal succession in these gelatinous species. Taken together, these findings support previous assertions that

  1. Not all jellyfish are equal: isotopic evidence for inter- and intraspecific variation in jellyfish trophic ecology.

    PubMed

    Fleming, Nicholas E C; Harrod, Chris; Newton, Jason; Houghton, Jonathan D R

    2015-01-01

    Jellyfish are highly topical within studies of pelagic food-webs and there is a growing realisation that their role is more complex than once thought. Efforts being made to include jellyfish within fisheries and ecosystem models are an important step forward, but our present understanding of their underlying trophic ecology can lead to their oversimplification in these models. Gelatinous zooplankton represent a polyphyletic assemblage spanning >2,000 species that inhabit coastal seas to the deep-ocean and employ a wide variety of foraging strategies. Despite this diversity, many contemporary modelling approaches include jellyfish as a single functional group feeding at one or two trophic levels at most. Recent reviews have drawn attention to this issue and highlighted the need for improved communication between biologists and theoreticians if this problem is to be overcome. We used stable isotopes to investigate the trophic ecology of three co-occurring scyphozoan jellyfish species (Aurelia aurita, Cyanea lamarckii and C. capillata) within a temperate, coastal food-web in the NE Atlantic. Using information on individual size, time of year and δ (13)C and δ (15)N stable isotope values, we examined: (1) whether all jellyfish could be considered as a single functional group, or showed distinct inter-specific differences in trophic ecology; (2) Were size-based shifts in trophic position, found previously in A. aurita, a common trait across species?; (3) When considered collectively, did the trophic position of three sympatric species remain constant over time? Differences in δ (15)N (trophic position) were evident between all three species, with size-based and temporal shifts in δ (15)N apparent in A. aurita and C. capillata. The isotopic niche width for all species combined increased throughout the season, reflecting temporal shifts in trophic position and seasonal succession in these gelatinous species. Taken together, these findings support previous assertions

  2. Jellyfish Stings and Their Management: A Review

    PubMed Central

    Cegolon, Luca; Heymann, William C.; Lange, John H.; Mastrangelo, Giuseppe

    2013-01-01

    Jellyfish (cnidarians) have a worldwide distribution. Despite most being harmless, some species may cause local and also systemic reactions. Treatment of jellyfish envenomation is directed at: alleviating the local effects of venom, preventing further nematocyst discharges and controlling systemic reactions, including shock. In severe cases, the most important step is stabilizing and maintaining vital functions. With some differences between species, there seems to be evidence and consensus on oral/topical analgesics, hot water and ice packs as effective painkillers and on 30 s application of domestic vinegar (4%–6% acetic acid) to prevent further discharge of unfired nematocysts remaining on the skin. Conversely, alcohol, methylated spirits and fresh water should be carefully avoided, since they could massively discharge nematocysts; pressure immobilization bandaging should also be avoided, as laboratory studies show that it stimulates additional venom discharge from nematocysts. Most treatment approaches are presently founded on relatively weak evidence; therefore, further research (especially randomized clinical trials) is strongly recommended. Dissemination of appropriate treatment modalities should be deployed to better inform and educate those at risk. Adequate signage should be placed at beaches to notify tourists of the jellyfish risk. Swimmers in risky areas should wear protective equipment. PMID:23434796

  3. Do resonating bells increase jellyfish swimming performance?

    NASA Astrophysics Data System (ADS)

    Hoover, Alexander; Miller, Laura

    2013-11-01

    A current question in swimming and flight is whether or not driving flexible appendages at their resonant frequency results in faster or more efficient locomotion. It has been suggested that jellyfish swim faster and/or more efficiently when the bell is driven at its resonant frequency. Previous work has modeled the jellyfish bell as a damped harmonic oscillator, and this simplified model suggests that work done by the bell is maximized when force is applied at the resonant frequency of the bell. We extend the idea of resonance phenomena of the jellyfish bell to a fluid structure interaction framework using the immersed boundary method. We first examine the effects of the bending stiffness of the bell on its resonant frequency. We then further our model with the inclusion of a ``muscular'' spring that connects the two sides of a 2D bell and drives it near its resonant frequency. We use this muscular spring to force the bell at varying frequencies and examine the work done by these springs and the resulting swimming speed. We finally augment our model with a flexible, passive bell margin to examine its role in propulsive efficiency.

  4. Early dentistry in Victoria, Australia.

    PubMed

    Atkinson, Henry

    2015-01-01

    At the time of settlement and in the years leading up to the establishment in 1884 of the Odontological Society of Victoria, dentistry was an unregulated activity practised simultaneously by those that had received the best apprenticeship training and those that had no training what-so-ever. Under the influence of dentists such as John Iliffe however, this situation was soon to change. In 1887 the first Dental Act was passed making it a legal requirement for anyone practicing dentistry to be registered. In 1890, the Melbourne Dental Hospital opened its doors to its first patients, and in 1897, the Australian College of Dentistry, later to become a school within the University of Melbourne, began teaching a dental course. Combined, these three moments in history lead to the eradication of the unscrupulous practitioner and laid the path for the development and professionalization of dentistry in the state of Victoria.

  5. Overview of Approach to 'Victoria'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Figure 1

    This image from the Mars Orbiter Camera aboard NASA's Mars Global Surveyor spacecraft shows an overview of 'Victoria Crater' and a portion of the area NASA's Mars Exploration Rover Opportunity has covered to reach the enormous depression.

    Images such as this one from the Mars Orbiter Camera on NASA's Mars Global Surveyor are helping scientists and engineers decide the best path for NASA's Mars Exploration Rover Opportunity as it approaches 'Victoria Crater.'

    In figure 1, a blue dot indicates 'Cape Verde' and a red dot 'Cabo Frio.' These two points mark the extent of the crater visible from the rover's position on its 945th Martian day, or sol (Sept. 20, 2006), a location it had reached two sols earlier and from which much of this monster depression was still out of sight. The green annotations indicate 'Duck Bay,' a location expected to allow a view to the other side of the crater. A dune, or ripple, is to the left of the crater, right in front of the green dot location. This is where the team initially talked about sending Opportunity for the rover's first view down into the crater. After further consideration, the team opted for a drive to the right of that ripple (south of the green dot) near the rim.

    The yellow lines that surround and intersect Victoria Crater are used to measure the crater and the distance to the far 'bays.' North is up. Victoria Crater is about 800 meters (half a mile) in diameter.

  6. Degradation of Victoria Crater, Mars

    NASA Technical Reports Server (NTRS)

    Wilson, Sharon A.; Grant, John A.; Cohen, Barbara A.; Golombek, Mathew P.; Geissler, Paul E.; Sullivan, Robert J.; Kirk, Randolph L.; Parker, Timothy J.

    2008-01-01

    The $\\sim$750 m diameter and $\\sim$75 m deep Victoria crater in Meridiani Planum, Mars, presents evidence for significant degradation including a low, serrated, raised rim characterized by alternating alcoves and promontories, a surrounding low relief annulus, and a floor partially covered by dunes. The amount and processes of degradation responsible for the modified appearance of Victoria crater were evaluated using images obtained in situ by the Mars Exploration Rover Opportunity in concert with a digital elevation model created using orbital HiRISE images. Opportunity traversed along the north and northwest rim and annulus, but sufficiently characterized features visible in the DEM to enable detailed measurements of rim relief, ejecta thickness, and wall slopes around the entire degraded, primary impact structure. Victoria retains a 5 m raised rim consisting of 1-2 m of uplifted rocks overlain by 3 m of ejecta at the rim crest. The rim is $\\sim$120 to 220 m wide and is surrounded by a dark annulus reaching an average of 590 m beyond the raised rim. Comparison between observed morphology and that expected for pristine craters 500 to 750 m across indicate the original, pristine crater was close to 600 m in diameter. Hence, the crater has been erosionally widened by approximately 150 m and infilled by about 50 m of sediments. Eolian processes are responsible for modification at Victoria, but lesser contributions from mass wasting or other processes cannot be ruled out. Erosion by prevailing winds is most significant along the exposed rim and upper walls and accounts for $\\sim$50 m widening across a WNW-ESE diameter. The volume of material eroded from the crater walls and rim is $\\sim$20% less than the volume of sediments partially filling the crater, indicating eolian infilling from sources outside the crater over time. The annulus formed when $\\sim$1 m deflation of the ejecta created a lag of more resistant hematite spherules that trapped darker, regional

  7. Degradation of Victoria Crater, Mars

    NASA Astrophysics Data System (ADS)

    Wilson, S. A.; Grant, J. A.; Cohen, B. A.; Golombek, M. P.; Geissler, P. E.; Sullivan, R. J.; Kirk, R. L.; Parker, T. J.

    2008-12-01

    The approximately 750 m diameter and 75 m deep Victoria crater in Meridiani Planum, Mars, presents evidence for significant degradation including a low, serrated, raised rim characterized by alternating alcoves and promontories, a surrounding low relief annulus, and a floor partially covered by dunes. The amount and processes of degradation responsible for the modified appearance of Victoria crater were evaluated using images obtained in situ by the Mars Exploration Rover Opportunity in concert with a digital elevation model (DEM) created using orbital HiRISE images. Opportunity traversed along the north and northwest rim and annulus and sufficiently characterized features visible in the DEM, thereby enabling detailed measurements of rim relief, ejecta thickness, and wall slopes around the entire degraded, primary impact structure. Victoria retains a 5 m raised rim consisting of 1 to 2 m of uplifted rocks overlain by 3 m of ejecta at the rim crest. The rim is 120 to 220 m wide and is surrounded by a dark annulus reaching an average of 590 m beyond the raised rim. Comparison between observed morphology and that expected for pristine craters 500 to 750 m across indicate the original, pristine crater was close to 600 m in diameter. Hence, the crater has been erosionally widened by approximately 150 m and infilled by about 50 m of sediments. Eolian processes are responsible for modification at Victoria, but lesser contributions from mass wasting or other processes cannot be ruled out. Erosion by prevailing winds is most significant along the exposed rim and upper walls and accounts for roughly 50 m widening across a WNW to ESE diameter. The volume of material eroded from the crater walls and rim is about 20 percent less than the volume of sediments partially filling the crater, indicating eolian infilling from sources outside the crater over time. The annulus formed when less than 1 m deflation of the ejecta created a lag of more resistant hematite spherules that

  8. Mechanical and scaling considerations for efficient jellyfish swimming

    NASA Astrophysics Data System (ADS)

    Hoover, Alexander; Miller, Laura; Griffith, Boyce

    2015-11-01

    With a fossil record dating over half a billion years, jellyfish represent one of the earliest examples of how multicellular organisms first organized into moving systems. Lacking an agonist-antagonist muscle pairing, jellyfish swim via a process of elastic deformation and recoil. Jellyfish propulsion is generated via the coordinated contraction of its elastic bell by its coronal swimming muscles and a complementary re-expansion that is passively driven by stored elastic energy. Recent studies have found jellyfish to be one of the most efficient swimmers due to its low energy expenditure in their forward movement. Using an immersed boundary framework, we will further examine the efficiency of jellyfish swimming by incorporating material models that are informed by the musculature present in jellyfish into a model of the elastic jellyfish bell in three dimensions. The fully-coupled fluid structure interaction problem is solved using an adaptive and parallelized version of the immersed boundary method (IBAMR). This model is then used to explore how variability in the mechanical properties of the bell affect the work done by the bell as well as the cost of transport related to jellyfish locomotion. We then examine how the efficiency of this system is affected by the Reynolds number.

  9. Occurrence of organo-arsenicals in jellyfishes and their mucus.

    PubMed

    Hanaoka, K; Ohno, H; Wada, N; Ueno, S; Goessler, W; Kuehnelt, D; Schlagenhaufen, C; Kaise, T; Irgolic, K J

    2001-08-01

    Water-soluble arsenic compound fractions were extracted from seven species of jellyfishes and subjected to analysis by high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS) for arsenicals. A low content of arsenic was found to be the characteristic of jellyfish. Arsenobetaine (AB) was the major arsenic compound without exception in the tissues of the jellyfish species and mucus-blobs collected from some of them. Although the arsenic content in Beroe cucumis, which preys on Bolinopsis mikado, was more than 13 times that in B. mikado, the chromatograms of these two species were similar in the distribution pattern of arsenicals. The nine species of jellyfishes including two species treated in the previous paper can be classified into arsenocholine (AC)-rich and AC-poor species. Jellyfishes belonging to Semaostamae were classified as AC-rich species.

  10. vVICTORIA Console Development: Design and Fabrication of VICTORIA Console Emulations

    DTIC Science & Technology

    2011-07-01

    Canada vVICTORIA Console Development Design and Fabrication of VICTORIA Console Emulations Contract Project Manager: Keith Bowden, 902 832 7862...intentionally left blank. vVICTORIA Console Development Design and Fabrication of VICTORIA Console Emulations Keith Bowden Earl Gosse Prepared...integration, optimum equipment configurations and human factors. Résumé …..... Le présent rapport porte sur le développement et la fabrication de

  11. 75 FR 13433 - Safety Zone; Invista Inc Facility Docks, Victoria Barge Canal, Victoria, TX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-22

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Invista Inc Facility Docks, Victoria Barge Canal, Victoria, TX AGENCY: Coast Guard, DHS. ACTION: Interim final rule with request for comments. SUMMARY: The Coast Guard is establishing a safety zone for a partial blockage of the Victoria Barge...

  12. 'Victoria Crater' from 'Duck Bay'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA's Mars rover Opportunity edged 3.7 meters (12 feet) closer to the top of the 'Duck Bay' alcove along the rim of 'Victoria Crater' during the rover's 952nd Martian day, or sol (overnight Sept. 27 to Sept. 28), and gained this vista of the crater. The rover's navigation camera took the seven exposures combined into this mosaic view of the crater's interior. This crater has been the mission's long-term destination for the past 21 Earth months.

    The far side of the crater is about 800 meters (one-half mile) away. The rim of the crater is composed of alternating promontories, rocky points towering approximately 70 meters (230 feet) above the crater floor, and recessed alcoves, such as Duck Bay. The bottom of the crater is covered by sand that has been shaped into ripples by the Martian wind. The rocky cliffs in the foreground have been informally named 'Cape Verde,' on the left, and 'Cabo Frio,' on the right.

    Victoria Crater is about five times wider than 'Endurance Crater,' which Opportunity spent six months examining in 2004, and about 40 times wider than 'Eagle Crater,' where Opportunity first landed. The great lure of Victoria is an expectation that the thick stack of geological layers exposed in the crater walls could reveal the record of past environmental conditions over a much greater span of time than Opportunity has read from rocks examined earlier in the mission.

    This view is presented as a cylindrical projection with geometric seam correction.

  13. Jellyfish Patch Detecting Using Low Latitude Remote Sensing System

    NASA Astrophysics Data System (ADS)

    Lee, J. S.; Jo, Y. H.

    2015-12-01

    Jellyfish can be asexual and sexual reproduction depending on the environment, and it has excellent environmental adaptability and reproduction than other sea creatures. If the marine environment become worse, jellyfish can take advantage in the competition for survival. Marine environmental changes caused by rapid climate change, dyke construction and land reclamation will increase the amount of jellyfish and as a result can lead to a various social and economic problems. In this study, jellyfish were observed in coastal area using a low-altitude Helikite remote sensing system for the first time. Helikite is a type of helium balloon plus a kite that can get the data with optical sensors for the desired spatial resolutions by adjusting the altitudes. In addition, it has an advantage that can monitor any objects for a long time at one place as long as the electric power and helium last. In this study, we observed the jellyfish patches using a digital camera in the Chesapeake Bay and estimate populations and size of jellyfish patches through image processing. Research results suggests that we can have long-term real-time observations for not only jellyfish, but also other harmful marine creatures.

  14. [Fluorescent proteins: physical-chemical properties and application in cell biology].

    PubMed

    Stepanenko, O V; Verkhusha, V V; Kuznetsova, I M; Turoverov, K K

    2007-01-01

    Green fluorescent protein (GFP) from jellyfish Aequorea victoria is the most extensively studied and widely used in cell biology protein. At present novel naturally occurring GFP-like proteins have been discovered and enhanced mutants of Aequorea GFP have been created. These mutants differ from wild-type GFP by stability, value of quantum yield, absorption and fluorescence spectra position and photochemical properties. GFP-like proteins are the fast growing family. This review is an attempt to characterize the main groups of GFP-like proteins, describe their structure and mechanisms of chromophore formation and summarize the main trends of their utilization as markers and biosensors in cell and molecular biology.

  15. Degradation of Victoria crater, Mars

    NASA Astrophysics Data System (ADS)

    Grant, John A.; Wilson, Sharon A.; Cohen, Barbara A.; Golombek, Matthew P.; Geissler, Paul E.; Sullivan, Robert J.; Kirk, Randolph L.; Parker, Timothy J.

    2008-11-01

    The ~750 m diameter and ~75 m deep Victoria crater in Meridiani Planum, Mars, is a degraded primary impact structure retaining a ~5 m raised rim consisting of 1-2 m of uplifted rocks overlain by ~3 m of ejecta at the rim crest. The rim is 120-220 m wide and is surrounded by a dark annulus reaching an average of 590 m beyond the raised rim. Comparison between observed morphology and that expected for pristine craters 500-750 m across indicates that the original, pristine crater was close to 600 m in diameter. Hence, the crater has been erosionally widened by ~150 m and infilled by ~50 m of sediments. Eolian processes are responsible for most crater modification, but lesser mass wasting or gully activity contributions cannot be ruled out. Erosion by prevailing winds is most significant along the exposed rim and upper walls and accounts for ~50 m widening across a WNW-ESE diameter. The volume of material eroded from the crater walls and rim is ~20% less than the volume of sediments partially filling the crater, indicating eolian infilling from sources outside the crater over time. The annulus formed when ~1 m deflation of the ejecta created a lag of more resistant hematite spherules that trapped <10-20 cm of darker, regional basaltic sands. Greater relief along the rim enabled meters of erosion. Comparison between Victoria and regional craters leads to definition of a crater degradation sequence dominated by eolian erosion and infilling over time.

  16. Passive mechanics in jellyfish-like locomotion

    NASA Astrophysics Data System (ADS)

    Wilson, Megan; Eldredge, Jeff

    2008-11-01

    The aim of this work is to identify possible benefits of passive flexibility in biologically-inspired locomotion. Substantial energy savings are likely achieved in natural locomotion by allowing a mix of actively controlled and passively responsive deformation. The jellyfish is a useful target of study, due to its relatively simple structure and the availability of recent kinematics and flow-field measurements. In this investigation, the jellyfish consists of a two-dimensional articulated system of rigid bodies linked by hinges. The kinematics -- expressed via the hinge angles -- are adapted from experimentally measured motion. The free swimming system is explored via high-fidelity numerical simulation with a viscous vortex particle method with coupled body dynamics. The computational tool allows the arbitrary designation of individual hinges as ``active'' or ``passive,'' to introduce a mix of flexibility into the system. In some cases, replacing an active hinge with a passive spring can enhance the mean swimming speed, thus reducing the power requirements of the system. Varying the stiffness and damping coefficients of the spring yield different locomotive results. The numerical solution is used to compute the finite-time Lyapunov exponents (FTLE) throughout the field. The FTLE fields reveal manifolds in the flow that act as transport barriers, uncovering otherwise unseen geometric characteristics of the flow field that add new insight into the locomotion mechanics.

  17. Evolution and functional diversity of jellyfish opsins.

    PubMed

    Suga, Hiroshi; Schmid, Volker; Gehring, Walter J

    2008-01-08

    Cnidaria are the most basal animal phylum possessing complex eyes [1]. Their eyes predominantly use ciliary photoreceptor cells (c-PRCs) like vertebrates, whereas insect eyes use rhabdomeric photoreceptor cells (r-PRCs) [1-4]. These two cell types show not only different cytoarchitectures but distinct phototransduction cascades, which are triggered by the respective types of opsins (e.g., [5]), ciliary opsins (c-opsins) and rhabdomeric opsins (r-opsins) [6]. Recent reports suggested that the c- and r-PRCs and their respective opsins diverged at least before the deuterostome-protostome split [7-9]. To study the earlier evolution of animal PRCs and opsins, we investigated two hydrozoan jellyfishes. We report here the first-characterized cnidarian opsins. Molecular phylogeny revealed that the cloned 20 jellyfish opsins, together with all the opsins from a hydra and some from a sea anemone, are more closely related to the c-opsins than to any other major opsin subfamily, indicating that the divergence of c- and r-opsins antedates the Cnidaria-Bilateria split. Possible scenarios of animal PRC evolution are discussed. Furthermore, Cladonema opsins show several distinct tissue- and stage-specific expression patterns. The expression of specific opsins in the eyes suggests a role in vision, whereas that in the gonads suggests a role in light-controlled release of gametes.

  18. Regulation of Growth and Metastases in an Estrogen Independent Breast Cancer Cell by Vitamin D Compounds

    DTIC Science & Technology

    2000-08-01

    micrometastases in the nude mouse, we used the EGFP fluorescent marker gene, cloned from the bioluminescent jellyfish Aequorea Victoria (previously...Utilizing our SUM-159PT GFP model system in vivo we can more efficiently examine the effects of vitamin D compounds to modulate invasion and metastasis...cells in nude mice. We previously reported that use of SUM-159PT cells expressing GFP enabled visualization of cancer cells in the mammary fat pad as

  19. Regulation of Growth and Metastases in an Estrogen Independent Breast Cancer Cell by Vitamin D Compounds

    DTIC Science & Technology

    2001-08-01

    jellyfish Aequorea Victoria (previously described in original grant proposal). Orthotopic implantation of SUMp159PTGFP was carried out to allow for the...metastatic expression of the inoculated cells in nude mice. We previously reported that use of SUM-159PT cells expressing GFP enabled visualization of...the brain and kidney. Resolution of SUM- 159PTGF cells was down to the single cell level, and high-level GFP expression was maintained in primary

  20. A fluid mechanical model for current-generating-feeding jellyfish

    NASA Astrophysics Data System (ADS)

    Peng, Jifeng; Dabiri, John

    2008-11-01

    Many jellyfish species, e.g. moon jellyfish Aurelia aurita, use body motion to generate fluid currents which carry their prey to the vicinity of their capture appendages. In this study, a model was developed to understand the fluid mechanics for this current-generating-feeding mode of jellyfish. The flow generated by free-swimming Aurelia aurita was measured using digital particle image velocimetry. The dynamics of prey (e.g., brine shrimp Artemia) in the flow field were described by a modified Maxey-Riley equation which takes into consideration the inertia of prey and the escape forces, which prey exert in the presence of predator. A Lagrangian analysis was used to identify the region of the flow in which prey can be captured by the jellyfish and the clearance rate was quantified. The study provides a new methodology to study biological current-generating-feeding and the transport and mixing of particles in fluid flow in general.

  1. Jellyfish blooms in China: Dominant species, causes and consequences.

    PubMed

    Dong, Zhijun; Liu, Dongyan; Keesing, John K

    2010-07-01

    Three jellyfish species, Aurelia aurita, Cyanea nozakii and Nemopilema nomurai, form large blooms in Chinese seas. We report on the distribution and increasing incidence of jellyfish blooms and their consequences in Chinese coastal seas and analyze their relationship to anthropogenically derived changes to the environment in order to determine the possible causes. A. aurita, C. nozakii and N. nomurai form blooms in the temperate Chinese seas including the northern East China Sea, Yellow Sea and Bohai Sea. N. nomurai forms offshore blooms while the other two species bloom mainly in inshore areas. Eutrophication, overfishing, habitat modification for aquaculture and climate change are all possible contributory factors facilitating plausible mechanisms for the proliferation of jellyfish blooms. In the absence of improvement in coastal marine ecosystem health, jellyfish blooms could be sustained and may even spread from the locations in which they now occur.

  2. Environmental forcing on jellyfish communities in a small temperate estuary.

    PubMed

    Primo, Ana Lígia; Marques, Sónia C; Falcão, Joana; Crespo, Daniel; Pardal, Miguel A; Azeiteiro, Ulisses M

    2012-08-01

    The impact of biological, hydrodynamic and large scale climatic variables on the jellyfish community of Mondego estuary was evaluated from 2003 to 2010. Plankton samples were collected at the downstream part of the estuary. Siphonophora Muggiaea atlantica and Diphyes spp. were the main jellyfish species. Jellyfish density was generally higher in summer and since 2005 densities had increased. Summer community analysis pointed out Acartia clausi, estuarine temperature and salinity as the main driven forces for the assemblage's structure. Also, Chl a, estuarine salinity, runoff and SST were identified as the major environmental factors influencing the siphonophores summer interannual variability. Temperature influenced directly and indirectly the community and fluctuation of jellyfish blooms in the Mondego estuary. This study represents a contribution to a better knowledge of the gelatinous plankton communities in small temperate estuaries.

  3. Environmental DNA reflects spatial and temporal jellyfish distribution

    PubMed Central

    Fukuda, Miho; Katsuhara, Koki R.; Fujiwara, Ayaka; Hidaka, Shunsuke; Yamamoto, Satoshi; Takahashi, Kohji; Masuda, Reiji

    2017-01-01

    Recent development of environmental DNA (eDNA) analysis allows us to survey underwater macro-organisms easily and cost effectively; however, there have been no reports on eDNA detection or quantification for jellyfish. Here we present the first report on an eDNA analysis of marine jellyfish using Japanese sea nettle (Chrysaora pacifica) as a model species by combining a tank experiment with spatial and temporal distribution surveys. We performed a tank experiment monitoring eDNA concentrations over a range of time intervals after the introduction of jellyfish, and quantified the eDNA concentrations by quantitative real-time PCR. The eDNA concentrations peaked twice, at 1 and 8 h after the beginning of the experiment, and became stable within 48 h. The estimated release rates of the eDNA in jellyfish were higher than the rates previously reported in fishes. A spatial survey was conducted in June 2014 in Maizuru Bay, Kyoto, in which eDNA was collected from surface water and sea floor water samples at 47 sites while jellyfish near surface water were counted on board by eye. The distribution of eDNA in the bay corresponded with the distribution of jellyfish inferred by visual observation, and the eDNA concentration in the bay was ~13 times higher on the sea floor than on the surface. The temporal survey was conducted from March to November 2014, in which jellyfish were counted by eye every morning while eDNA was collected from surface and sea floor water at three sampling points along a pier once a month. The temporal fluctuation pattern of the eDNA concentrations and the numbers of observed individuals were well correlated. We conclude that an eDNA approach is applicable for jellyfish species in the ocean. PMID:28245277

  4. Environmental DNA reflects spatial and temporal jellyfish distribution.

    PubMed

    Minamoto, Toshifumi; Fukuda, Miho; Katsuhara, Koki R; Fujiwara, Ayaka; Hidaka, Shunsuke; Yamamoto, Satoshi; Takahashi, Kohji; Masuda, Reiji

    2017-01-01

    Recent development of environmental DNA (eDNA) analysis allows us to survey underwater macro-organisms easily and cost effectively; however, there have been no reports on eDNA detection or quantification for jellyfish. Here we present the first report on an eDNA analysis of marine jellyfish using Japanese sea nettle (Chrysaora pacifica) as a model species by combining a tank experiment with spatial and temporal distribution surveys. We performed a tank experiment monitoring eDNA concentrations over a range of time intervals after the introduction of jellyfish, and quantified the eDNA concentrations by quantitative real-time PCR. The eDNA concentrations peaked twice, at 1 and 8 h after the beginning of the experiment, and became stable within 48 h. The estimated release rates of the eDNA in jellyfish were higher than the rates previously reported in fishes. A spatial survey was conducted in June 2014 in Maizuru Bay, Kyoto, in which eDNA was collected from surface water and sea floor water samples at 47 sites while jellyfish near surface water were counted on board by eye. The distribution of eDNA in the bay corresponded with the distribution of jellyfish inferred by visual observation, and the eDNA concentration in the bay was ~13 times higher on the sea floor than on the surface. The temporal survey was conducted from March to November 2014, in which jellyfish were counted by eye every morning while eDNA was collected from surface and sea floor water at three sampling points along a pier once a month. The temporal fluctuation pattern of the eDNA concentrations and the numbers of observed individuals were well correlated. We conclude that an eDNA approach is applicable for jellyfish species in the ocean.

  5. Degradation of Victoria crater, Mars

    USGS Publications Warehouse

    Grant, J. A.; Wilson, S.A.; Cohen, B. A.; Golombek, M.P.; Geissler, P.E.; Sullivan, R.J.; Kirk, R.L.; Parker, T.J.

    2008-01-01

    The ???750 m diameter and ???75 m deep Victoria crater in Meridiani Planum, Mars, is a degraded primary impact structure retaining a ???5 m raised rim consisting of 1-2 m of uplifted rocks overlain by ???3 m of ejecta at the rim crest. The rim is 120-220 m wide and is surrounded by a dark annulus reaching an average of 590 m beyond the raised rim. Comparison between observed morphology and that expected for pristine craters 500-750 m across indicates that the original, pristine crater was close to 600 m in diameter. Hence, the crater has been erosionally widened by ???150 m and infilled by ???50 m of sediments. Eolian processes are responsible for most crater modification, but lesser mass wasting or gully activity contributions cannot be ruled out. Erosion by prevailing winds is most significant along the exposed rim and upper walls and accounts for ???50 m widening across a WNW-ESE diameter. The volume of material eroded from the crater walls and rim is ???20% less than the volume of sediments partially filling the crater, indicating eolian infilling from sources outside the crater over time. The annulus formed when ???1 m deflation of the ejecta created a lag of more resistant hematite spherules that trapped <10-20 cm of darker, regional basaltic sands. Greater relief along the rim enabled meters of erosion. Comparison between Victoria and regional craters leads to definition of a crater degradation sequence dominated by eolian erosion and infilling over time. Copyright 2008 by the American Geophysical Union.

  6. Measles surveillance in Victoria, Australia.

    PubMed Central

    Wang, Yung-Hsuan J.; Andrews, Ross M.; Lambert, Stephen B.

    2006-01-01

    OBJECTIVE: Many countries are implementing measles elimination strategies. In Australia, the State of Victoria has conducted enhanced measles surveillance since 1997 using case interviews and home-based specimen collection for laboratory confirmation. We attempted to identify features of notified cases that would better target surveillance resources. METHODS: We retrospectively classified notifications received from 1998 to 2003 as having been received in an epidemic (one or more laboratory-confirmed cases) or an interepidemic period (no laboratory-confirmed cases). We labelled the first case notified in any epidemic period that was not laboratory-confirmed at the time of notification as a "sentinel case". To maximize detection of sentinel cases while minimizing the follow-up of eventually discarded notifications, we generated algorithms using sentinel cases and interepidemic notifications. FINDINGS: We identified 10 sentinel cases with 422 interepidemic notifications from 1281 Victorian notifications. Sentinel cases were more likely to report fever at rash onset (odds ratio (OR) 15.7, 95% confidence interval (CI) CI: 2.1-688.9), cough (OR 10.4, 95% CI: 1.4-456.7), conjunctivitis (OR 7.9, 95% CI: 1.8-39.1), or year of birth between 1968 and 1981 (OR 31.8, 95% CI: 6.7-162.3). Prospective application of an algorithm consisting of fever at rash onset or born between 1968 and 1981 in the review period would have detected all sentinel cases and avoided the need for enhanced follow-up of 162 of the 422 eventually discarded notifications. CONCLUSION: Elimination strategies should be refined to suit regional and local priorities. The prospective application of an algorithm in Victoria is likely to reduce enhanced measles surveillance resource use in interepidemic periods, while still detecting early cases during measles outbreaks. PMID:16501727

  7. 'Lyell' Panorama inside Victoria Crater

    NASA Technical Reports Server (NTRS)

    2008-01-01

    During four months prior to the fourth anniversary of its landing on Mars, NASA's Mars Exploration Rover Opportunity examined rocks inside an alcove called 'Duck Bay' in the western portion of Victoria Crater. The main body of the crater appears in the upper right of this stereo panorama, with the far side of the crater lying about 800 meters (half a mile) away. Bracketing that part of the view are two promontories on the crater's rim at either side of Duck Bay. They are 'Cape Verde,' about 6 meters (20 feet) tall, on the left, and 'Cabo Frio,' about 15 meters (50 feet) tall, on the right. The rest of the image, other than sky and portions of the rover, is ground within Duck Bay.

    Opportunity's targets of study during the last quarter of 2007 were rock layers within a band exposed around the interior of the crater, about 6 meters (20 feet) from the rim. Bright rocks within the band are visible in the foreground of the panorama. The rover science team assigned informal names to three subdivisions of the band: 'Steno,' 'Smith,' and 'Lyell.'

    This view combines many images taken by Opportunity's panoramic camera (Pancam) from the 1,332nd through 1,379th Martian days, or sols, of the mission (Oct. 23 to Dec. 11, 2007). Images taken through Pancam filters centered on wavelengths of 753 nanometers, 535 nanometers and 432 nanometers were mixed to produce an approximately true-color panorama. Some visible patterns in dark and light tones are the result of combining frames that were affected by dust on the front sapphire window of the rover's camera.

    Opportunity landed on Jan. 25, 2004, Universal Time, (Jan. 24, Pacific Time) inside a much smaller crater about 6 kilometers (4 miles) north of Victoria Crater, to begin a surface mission designed to last 3 months and drive about 600 meters (0.4 mile).

  8. Scyphozoan jellyfish venom metalloproteinases and their role in the cytotoxicity.

    PubMed

    Lee, Hyunkyoung; Jung, Eun-sun; Kang, Changkeun; Yoon, Won Duk; Kim, Jong-Shu; Kim, Euikyung

    2011-09-01

    The present study, for the first time, comparatively investigated the enzymatic activities (proteases and hyaluronidases) in the venoms of four Scyphozoan jellyfish species, including Nemopilema nomurai, Rhopilema esculenta, Cyanea nozakii, and Aurelia aurita. For this, various zymographic analyses were performed using assay specific substrates. Interestingly, all the four jellyfish venoms showed gelatinolytic, caseinolytic, and fibrinolytic activities, each of which contains a multitude of enzyme components with molecular weights between 17 and 130 kDa. These four jellyfish venoms demonstrated a huge variation in their proteolytic activities in quantitative and qualitative manner depending on the species. Most of these enzymatic activities were disappeared by the treatment of 1,10-phenanthroline, suggesting they might be belonged to metalloproteinases. Toxicological significance of these venom proteases was examined by comparing their proteolytic activity and the cytotoxicity in NIH 3T3 cells. The relative cytotoxic potency was C. nozakii > N. nomurai > A. aurita > R. esculenta. The cytotoxicity of jellyfish venom shows a positive correlation with its overall proteolytic activity. The metalloproteinases appear to play an important role in the induction of jellyfish venom toxicities. In conclusion, the present report proposes a novel finding of Scyphozoan jellyfish venom metalloproteinases and their potential role in the cytotoxicity.

  9. Muscular Control of Turning and Maneuvering in Jellyfish Bells

    NASA Astrophysics Data System (ADS)

    Hoover, Alexander; Miller, Laura; Griffith, Boyce

    2014-11-01

    Jellyfish represent one of the earliest and simplest examples of swimming by a macroscopic organism. Contractions of an elastic bell that expels water are driven by coronal swimming muscles. The re-expansion of the bell is passively driven by stored elastic energy. A current question in jellyfish propulsion is how the underlying neuromuscular organization of their bell allows for maneuvering. Using an immersed boundary framework, we will examine the mechanics of swimming by incorporating material models that are informed by the musculature present in jellyfish into a model of the elastic jellyfish bell in three dimensions. The fully-coupled fluid structure interaction problem is solved using an adaptive and parallelized version of the immersed boundary method (IBAMR). We then use this model to understand how variability in the muscular activation patterns allows for complicated swimming behavior, such as steering. We will compare the results of the simulations with the actual turning maneuvers of several species of jellyfish. Numerical flow fields will also be compared to those produced by actual jellyfish using particle image velocimetry (PIV).

  10. Subducting slabs: Jellyfishes in the Earth's mantle

    NASA Astrophysics Data System (ADS)

    Loiselet, Christelle; Braun, Jean; Husson, Laurent; Le Carlier de Veslud, Christian; Thieulot, Cedric; Yamato, Philippe; Grujic, Djordje

    2010-08-01

    The constantly improving resolution of geophysical data, seismic tomography and seismicity in particular, shows that the lithosphere does not subduct as a slab of uniform thickness but is rather thinned in the upper mantle and thickened around the transition zone between the upper and lower mantle. This observation has traditionally been interpreted as evidence for the buckling and piling of slabs at the boundary between the upper and lower mantle, where a strong contrast in viscosity may exist and cause resistance to the penetration of slabs into the lower mantle. The distribution and character of seismicity reveal, however, that slabs undergo vertical extension in the upper mantle and compression near the transition zone. In this paper, we demonstrate that during the subduction process, the shape of low viscosity slabs (1 to 100 times more viscous than the surrounding mantle) evolves toward an inverted plume shape that we coin jellyfish. Results of a 3D numerical model show that the leading tip of slabs deform toward a rounded head skirted by lateral tentacles that emerge from the sides of the jellyfish head. The head is linked to the body of the subducting slab by a thin tail. A complete parametric study reveals that subducting slabs may achieve a variety of shapes, in good agreement with the diversity of natural slab shapes evidenced by seismic tomography. Our work also suggests that the slab to mantle viscosity ratio in the Earth is most likely to be lower than 100. However, the sensitivity of slab shapes to upper and lower mantle viscosities and densities, which remain poorly constrained by independent evidence, precludes any systematic deciphering of the observations.

  11. Subducting Slabs: Jellyfishes in the Earth's Mantle

    NASA Astrophysics Data System (ADS)

    Loiselet, C.; Braun, J.; Husson, L.; Le Carlier de Veslud, C.; Thieulot, C.; Yamato, P.; Grujic, D.

    2010-12-01

    The constantly improving resolution of geophysical data, seismic tomography and seismicity in particular, shows that the lithosphere does not subduct as a slab of uniform thickness but is rather thinned in the upper mantle and thickened around the transition zone between the upper and lower mantle. This observation has traditionally been interpreted as evidence for the buckling and piling of slabs at the boundary between the upper and lower mantle, where a strong contrast in viscosity may exist and cause resistance to the penetration of slabs into the lower mantle. The distribution and character of seismicity reveal, however, that slabs undergo vertical extension in the upper mantle and compression near the transition zone. In this paper, we demonstrate that during the subduction process, the shape of low viscosity slabs (1 to 100 times more viscous than the surrounding mantle) evolves toward an inverted plume shape that we coin jellyfish. Results of a 3D numerical model show that the leading tip of slabs deform toward a rounded head skirted by lateral tentacles that emerge from the sides of the jellyfish head. The head is linked to the body of the subducting slab by a thin tail. A complete parametric study reveals that subducting slabs may achieve a variety of shapes, in good agreement with the diversity of natural slab shapes evidenced by seismic tomography. Our work also suggests that the slab to mantle viscosity ratio in the Earth is most likely to be lower than 100. However, the sensitivity of slab shapes to upper and lower mantle viscosities and densities, which remain poorly constrained by independent evidence, precludes any systematic deciphering of the observations.

  12. JELLYFISH GALAXY CANDIDATES AT LOW REDSHIFT

    SciTech Connect

    Poggianti, B. M.; Fasano, G.; Omizzolo, A.; Gullieuszik, M.; Bettoni, D.; Paccagnella, A.; Moretti, A.; D’Onofrio, M.; Jaffé, Y. L.; Vulcani, B.; Fritz, J.; Couch, W.

    2016-03-15

    Galaxies that are being stripped of their gas can sometimes be recognized from their optical appearance. Extreme examples of stripped galaxies are the so-called “jellyfish galaxies” that exhibit tentacles of debris material with a characteristic jellyfish morphology. We have conducted the first systematic search for galaxies that are being stripped of their gas at low-z (z = 0.04−0.07) in different environments, selecting galaxies with varying degrees of morphological evidence for stripping. We have visually inspected B- and V-band images and identified 344 candidates in 71 galaxy clusters of the OMEGAWINGS+WINGS sample and 75 candidates in groups and lower mass structures in the PM2GC sample. We present the atlas of stripping candidates and a first analysis of their environment and their basic properties, such as morphologies, star formation rates and galaxy stellar masses. Candidates are found in all clusters and at all clustercentric radii, and their number does not correlate with the cluster velocity dispersion σ or X-ray luminosity L{sub X}. Interestingly, convincing cases of candidates are also found in groups and lower mass halos (10{sup 11}−10{sup 14}M{sub ⊙}), although the physical mechanism at work needs to be securely identified. All the candidates are disky, have stellar masses ranging from log M/M{sub ⊙} < 9 to > 11.5 and the majority of them form stars at a rate that is on average a factor of 2 higher (2.5σ) compared to non-stripped galaxies of similar mass. The few post-starburst and passive candidates have weak stripping evidence. We conclude that disturbed morphologies suggestive of stripping phenomena are ubiquitous in clusters and could be present even in groups and low mass halos. Further studies will reveal the physics of the gas stripping and clarify the mechanisms at work.

  13. Jellyfish Galaxy Candidates at Low Redshift

    NASA Astrophysics Data System (ADS)

    Poggianti, B. M.; Fasano, G.; Omizzolo, A.; Gullieuszik, M.; Bettoni, D.; Moretti, A.; Paccagnella, A.; Jaffé, Y. L.; Vulcani, B.; Fritz, J.; Couch, W.; D'Onofrio, M.

    2016-03-01

    Galaxies that are being stripped of their gas can sometimes be recognized from their optical appearance. Extreme examples of stripped galaxies are the so-called “jellyfish galaxies” that exhibit tentacles of debris material with a characteristic jellyfish morphology. We have conducted the first systematic search for galaxies that are being stripped of their gas at low-z (z = 0.04-0.07) in different environments, selecting galaxies with varying degrees of morphological evidence for stripping. We have visually inspected B- and V-band images and identified 344 candidates in 71 galaxy clusters of the OMEGAWINGS+WINGS sample and 75 candidates in groups and lower mass structures in the PM2GC sample. We present the atlas of stripping candidates and a first analysis of their environment and their basic properties, such as morphologies, star formation rates and galaxy stellar masses. Candidates are found in all clusters and at all clustercentric radii, and their number does not correlate with the cluster velocity dispersion σ or X-ray luminosity LX. Interestingly, convincing cases of candidates are also found in groups and lower mass halos (1011-1014M⊙), although the physical mechanism at work needs to be securely identified. All the candidates are disky, have stellar masses ranging from log M/M⊙ < 9 to > 11.5 and the majority of them form stars at a rate that is on average a factor of 2 higher (2.5σ) compared to non-stripped galaxies of similar mass. The few post-starburst and passive candidates have weak stripping evidence. We conclude that disturbed morphologies suggestive of stripping phenomena are ubiquitous in clusters and could be present even in groups and low mass halos. Further studies will reveal the physics of the gas stripping and clarify the mechanisms at work.

  14. Chironex fleckeri (Box Jellyfish) Venom Proteins

    PubMed Central

    Brinkman, Diane L.; Konstantakopoulos, Nicki; McInerney, Bernie V.; Mulvenna, Jason; Seymour, Jamie E.; Isbister, Geoffrey K.; Hodgson, Wayne C.

    2014-01-01

    The box jellyfish Chironex fleckeri produces extremely potent and rapid-acting venom that is harmful to humans and lethal to prey. Here, we describe the characterization of two C. fleckeri venom proteins, CfTX-A (∼40 kDa) and CfTX-B (∼42 kDa), which were isolated from C. fleckeri venom using size exclusion chromatography and cation exchange chromatography. Full-length cDNA sequences encoding CfTX-A and -B and a third putative toxin, CfTX-Bt, were subsequently retrieved from a C. fleckeri tentacle cDNA library. Bioinformatic analyses revealed that the new toxins belong to a small family of potent cnidarian pore-forming toxins that includes two other C. fleckeri toxins, CfTX-1 and CfTX-2. Phylogenetic inferences from amino acid sequences of the toxin family grouped CfTX-A, -B, and -Bt in a separate clade from CfTX-1 and -2, suggesting that the C. fleckeri toxins have diversified structurally and functionally during evolution. Comparative bioactivity assays revealed that CfTX-1/2 (25 μg kg−1) caused profound effects on the cardiovascular system of anesthetized rats, whereas CfTX-A/B elicited only minor effects at the same dose. Conversely, the hemolytic activity of CfTX-A/B (HU50 = 5 ng ml−1) was at least 30 times greater than that of CfTX-1/2. Structural homology between the cubozoan toxins and insecticidal three-domain Cry toxins (δ-endotoxins) suggests that the toxins have a similar pore-forming mechanism of action involving α-helices of the N-terminal domain, whereas structural diversification among toxin members may modulate target specificity. Expansion of the cnidarian toxin family therefore provides new insights into the evolutionary diversification of box jellyfish toxins from a structural and functional perspective. PMID:24403082

  15. Prediction, location, collection and transport of jellyfish (Cnidaria) and their polyps.

    PubMed

    Pierce, Justin

    2009-03-01

    With growing interest in research and display of living jellyfish workers are realizing the difficulty in obtaining and maintaining a healthy collection consistently. This report identifies the causes for the uncertainty in locating specimens and summarizes the latest technology, techniques and avenues for acquiring jellyfish for captive maintenance. Responsibility inherent with jellyfish transport for the prevention of incidental escape is also discussed.

  16. Identification of genetically and oceanographically distinct blooms of jellyfish

    PubMed Central

    Lee, Patricia L. M.; Dawson, Michael N; Neill, Simon P.; Robins, Peter E.; Houghton, Jonathan D. R.; Doyle, Thomas K.; Hays, Graeme C.

    2013-01-01

    Reports of nuisance jellyfish blooms have increased worldwide during the last half-century, but the possible causes remain unclear. A persistent difficulty lies in identifying whether blooms occur owing to local or regional processes. This issue can be resolved, in part, by establishing the geographical scales of connectivity among locations, which may be addressed using genetic analyses and oceanographic modelling. We used landscape genetics and Lagrangian modelling of oceanographic dispersal to explore patterns of connectivity in the scyphozoan jellyfish Rhizostoma octopus, which occurs en masse at locations in the Irish Sea and northeastern Atlantic. We found significant genetic structure distinguishing three populations, with both consistencies and inconsistencies with prevailing physical oceanographic patterns. Our analyses identify locations where blooms occur in apparently geographically isolated populations, locations where blooms may be the source or result of migrants, and a location where blooms do not occur consistently and jellyfish are mostly immigrant. Our interdisciplinary approach thus provides a means to ascertain the geographical origins of jellyfish in outbreaks, which may have wide utility as increased international efforts investigate jellyfish blooms. PMID:23287405

  17. Identification of genetically and oceanographically distinct blooms of jellyfish.

    PubMed

    Lee, Patricia L M; Dawson, Michael N; Neill, Simon P; Robins, Peter E; Houghton, Jonathan D R; Doyle, Thomas K; Hays, Graeme C

    2013-03-06

    Reports of nuisance jellyfish blooms have increased worldwide during the last half-century, but the possible causes remain unclear. A persistent difficulty lies in identifying whether blooms occur owing to local or regional processes. This issue can be resolved, in part, by establishing the geographical scales of connectivity among locations, which may be addressed using genetic analyses and oceanographic modelling. We used landscape genetics and Lagrangian modelling of oceanographic dispersal to explore patterns of connectivity in the scyphozoan jellyfish Rhizostoma octopus, which occurs en masse at locations in the Irish Sea and northeastern Atlantic. We found significant genetic structure distinguishing three populations, with both consistencies and inconsistencies with prevailing physical oceanographic patterns. Our analyses identify locations where blooms occur in apparently geographically isolated populations, locations where blooms may be the source or result of migrants, and a location where blooms do not occur consistently and jellyfish are mostly immigrant. Our interdisciplinary approach thus provides a means to ascertain the geographical origins of jellyfish in outbreaks, which may have wide utility as increased international efforts investigate jellyfish blooms.

  18. The elusive life cycle of scyphozoan jellyfish – metagenesis revisited

    PubMed Central

    Ceh, Janja; Gonzalez, Jorge; Pacheco, Aldo S.; Riascos, José M.

    2015-01-01

    Massive proliferations of scyphozoan jellyfish considerably affect human industries and irreversibly change food webs. Efforts to understand the role of jellyfish in marine ecosystems are based on a life cycle model described 200 years ago. According to this paradigm the pelagic medusae is considered seasonal and alternates with the benthic polyp stage from which it derives. However, we provide evidence that a) the occurrence of several species of medusae is not restricted to a season in the year, they overwinter, b) polyp- and medusa generations are neither temporally nor spatially separated, and c) “metagenesis” which is defined as the alternation between sexual and asexual generations does not always occur. Hence we recommend additions to the current model and argue that the scyphozoan life cycle should be considered multi-modal, rather than metagenetic. The implications of these findings for jellyfish proliferations, including possible consequences and associated environmental drivers, are discussed. PMID:26153534

  19. The elusive life cycle of scyphozoan jellyfish--metagenesis revisited.

    PubMed

    Ceh, Janja; Gonzalez, Jorge; Pacheco, Aldo S; Riascos, José M

    2015-07-08

    Massive proliferations of scyphozoan jellyfish considerably affect human industries and irreversibly change food webs. Efforts to understand the role of jellyfish in marine ecosystems are based on a life cycle model described 200 years ago. According to this paradigm the pelagic medusae is considered seasonal and alternates with the benthic polyp stage from which it derives. However, we provide evidence that a) the occurrence of several species of medusae is not restricted to a season in the year, they overwinter, b) polyp- and medusa generations are neither temporally nor spatially separated, and c) "metagenesis" which is defined as the alternation between sexual and asexual generations does not always occur. Hence we recommend additions to the current model and argue that the scyphozoan life cycle should be considered multi-modal, rather than metagenetic. The implications of these findings for jellyfish proliferations, including possible consequences and associated environmental drivers, are discussed.

  20. Ephyra jellyfish as a new model for ecotoxicological bioassays.

    PubMed

    Faimali, M; Garaventa, F; Piazza, V; Costa, E; Greco, G; Mazzola, V; Beltrandi, M; Bongiovanni, E; Lavorano, S; Gnone, G

    2014-02-01

    The aim of this study was a preliminary investigation on the possibility of using the ephyra of Scyphozoan jellyfish Aurelia aurita (Linnaeus, 1758), the common moon jellyfish, as an innovative model organism in marine ecotoxicology. A series of sequential experiments have been carried out in laboratory in order to investigate the influence of different culturing and methodological parameters (temperature, photoperiod, ephyrae density and age) on behavioural end-points (% of Frequency of Pulsations) and standardize a testing protocol. After that, the organisms have been exposed to two well known reference toxic compounds (Cadmium Nitrate and SDS) in order to analyse the acute and behavioural responses during static exposure. Results of this work indicate that the proposed behavioural end-point, frequency of pulsations (Fp), is an easily measurable one and can be used coupled with an acute one (immobilization) and that ephyrae of jellyfish are very promising model organisms for ecotoxicological investigation.

  1. The elusive life cycle of scyphozoan jellyfish - metagenesis revisited

    NASA Astrophysics Data System (ADS)

    Ceh, Janja; Gonzalez, Jorge; Pacheco, Aldo S.; Riascos, José M.

    2015-07-01

    Massive proliferations of scyphozoan jellyfish considerably affect human industries and irreversibly change food webs. Efforts to understand the role of jellyfish in marine ecosystems are based on a life cycle model described 200 years ago. According to this paradigm the pelagic medusae is considered seasonal and alternates with the benthic polyp stage from which it derives. However, we provide evidence that a) the occurrence of several species of medusae is not restricted to a season in the year, they overwinter, b) polyp- and medusa generations are neither temporally nor spatially separated, and c) “metagenesis” which is defined as the alternation between sexual and asexual generations does not always occur. Hence we recommend additions to the current model and argue that the scyphozoan life cycle should be considered multi-modal, rather than metagenetic. The implications of these findings for jellyfish proliferations, including possible consequences and associated environmental drivers, are discussed.

  2. Mandatory bicycle helmet use--Victoria, Australia.

    PubMed

    1993-05-14

    On July 1, 1990, the first statewide law in Australia requiring wearing of an approved safety helmet by all bicyclists became effective in Victoria (1989 population: approximately 4.3 million) (Figure 1). Implementation of the law was preceded by a decade-long campaign to promote helmet use among the estimated 2.2 million persons who ride bicycles; the campaign included educational programs; mass media publicity; financial incentives; and efforts by professional, community, and bicycle groups (1,2). This report assesses helmet law enforcement, helmet use, and injuries related to bicycling in Victoria.

  3. Opportunity at Work Inside Victoria Crater

    NASA Technical Reports Server (NTRS)

    2007-01-01

    NASA Mars Exploration Rover Opportunity used its front hazard-identification camera to capture this wide-angle view of its robotic arm extended to a rock in a bright-toned layer inside Victoria Crater.

    The image was taken during the rover's 1,322nd Martian day, or sol (Oct. 13, 2007).

    Victoria Crater has a scalloped shape of alternating alcoves and promontories around the crater's circumference. Opportunity descended into the crater two weeks earlier, within an alcove called 'Duck Bay.' Counterclockwise around the rim, just to the right of the arm in this image, is a promontory called 'Cabo Frio.'

  4. Monitoring yeast intracellular Ca2+ levels using an in vivo bioluminescence assay.

    PubMed

    Tisi, Renata; Martegani, Enzo; Brandão, Rogelio L

    2015-02-02

    This protocol describes the use of the jellyfish Aequorea victoria aequorin protein to measure Ca(2+) levels in living yeast cells. All yeast strains to be analyzed must express the A. victoria apoprotein of the aequorin calcium biosensor, to be reconstituted into fully active aequorin by association with its cofactor, coelenterazine, which cannot be synthesized by yeast itself. The simplest way to achieve reconstitution is to transform yeast cells with a vector driving apoaequorin expression, and then supply commercially available coelenterazine cofactor in the medium. Coelenterazine is a hydrophobic molecule and is able to permeate yeast cells.

  5. Looking Forward: Community Gateways at Victoria University

    ERIC Educational Resources Information Center

    Mountford, Christine

    2011-01-01

    The mission and values of Victoria University provide the underlying criteria for the development and implementation of the Community Gateways initiative, which aims to transform the lives of those living in the west of Melbourne through the power of further education. Community Gateways takes the university into the community by providing career…

  6. View from Southwest of Victoria Crater

    NASA Technical Reports Server (NTRS)

    2009-01-01

    This mosaic of frames from the navigation camera on NASA's Mars Exploration Rover Opportunity gives a view to the northeast from the rover's position on its 1,687th Martian day, or sol (Oct. 22, 2008).

    By that date, Opportunity had driven southwestward from Victoria Crater, beginning a long trek toward a larger crater, Endeavour.

  7. Deselection: At the University of Victoria Library.

    ERIC Educational Resources Information Center

    Signori, Donna

    1985-01-01

    Presents a brief overview of weeding history at the University of Victoria library, an outline and evaluation of criteria and methodology proposed by a deselection task group and adopted for 1982 weeding project, and a summary of results and observations from pilot projects and policy proposals. Sixteen references are cited. (EJS)

  8. Jellyfish Bioactive Compounds: Methods for Wet-Lab Work

    PubMed Central

    Frazão, Bárbara; Antunes, Agostinho

    2016-01-01

    The study of bioactive compounds from marine animals has provided, over time, an endless source of interesting molecules. Jellyfish are commonly targets of study due to their toxic proteins. However, there is a gap in reviewing successful wet-lab methods employed in these animals, which compromises the fast progress in the detection of related biomolecules. Here, we provide a compilation of the most effective wet-lab methodologies for jellyfish venom extraction prior to proteomic analysis—separation, identification and toxicity assays. This includes SDS-PAGE, 2DE, gel chromatography, HPLC, DEAE, LC-MS, MALDI, Western blot, hemolytic assay, antimicrobial assay and protease activity assay. For a more comprehensive approach, jellyfish toxicity studies should further consider transcriptome sequencing. We reviewed such methodologies and other genomic techniques used prior to the deep sequencing of transcripts, including RNA extraction, construction of cDNA libraries and RACE. Overall, we provide an overview of the most promising methods and their successful implementation for optimizing time and effort when studying jellyfish. PMID:27077869

  9. Skin and Systemic Manifestations of Jellyfish Stings in Iraqi Fishermen

    PubMed Central

    Al-Rubiay, KK; Al-Musaoi, HA; Alrubaiy, L; Al-Freje, MG

    2009-01-01

    Background: Jellyfish stings are common worldwide with an estimated 150 million cases annually, and their stings cause a wide range of clinical manifestations from skin inflammation to cardiovascular and respiratory collapse. No studies on jellyfish stings have been carried out in Basra, Iraq. Objectives: To describe the immediate and delayed skin reactions to White Jellyfish (Rhizostoma sp.) stings and the types of local treatment used by fishermen. Methods and Materials: 150 fishermen were enrolled at three Marine stations in Basra, Iraq. Demographic data, types of skin reactions, systemic manifestations and kinds of treatments were collected. Results: Overall, 79% of fishermen in all three Marine stations gave a history of having been stung. The common sites of sings were the hands and arms followed by the legs. Most fishermen claimed that stings led to skin reactions within 5 minutes. The presenting complaints were itching, burning sensation, and erythematic wheals. A few days after the sting, new groups of painless and itchy erythematous monomorphic papular rashes developed at the site of the sting in 62% of cases as a delayed type of skin reaction that resolved spontaneously. The local remedies commonly used by the fishermen were seawater, tap water and ice. A few fishermen considered stings as insignificant and did not think there was a need to seek medical help. Conclusions: We conclude that jellyfish causes many stings among fishermen in the Basra region. Their stings lead to immediate and delayed skin reactions. Self-treatment by topical remedies is common. PMID:21483513

  10. Simulation of prolate swimming jellyfish with jet-based locomotion

    NASA Astrophysics Data System (ADS)

    Park, Sung Goon; Kim, Boyoung; Lee, Jin; Huang, Wei-Xi; Sung, Hyung Jin

    2014-11-01

    The hydrodynamic patterns in the wake of swimming jellyfish are based on the bell morphology. Jellyfish with a prolate bell morphology form a clear jet structure in the wake. A three-dimensional computational model was used to analyze the hydrodynamic patterns. The Froude propulsion efficiency, defined by the ratio of the value of the energy required to deform the elastic bell to the value of the average center velocity multiplied by the thrust, was compared with different forms of the elastic bell deformation. The immersed boundary method was adopted to consider the interaction between the swimming jellyfish and surrounding fluid. Due to the effect of the momentum transferred to the surrounding fluid by the bell deformation, the rotational fluid mass was formed, called vortices. The vortex structures in the wake of prolate swimming jellyfish were elucidated in detail in both quantitative and qualitative ways. A dimensionless temporal parameter was employed to investigate the vortex formation process quantitatively. The starting/stopping vortex structures were generated during the contraction/relaxation phase. During the early stage of the contraction, the vortex structures were mainly generated by the stroke, then the ejected fluid was entrained into the vortex structures. This study was supported by the Creative Research Initiatives (No.2014-001493) program of the National Research Foundation of Korea (MSIP).

  11. Jellyfish Bioactive Compounds: Methods for Wet-Lab Work.

    PubMed

    Frazão, Bárbara; Antunes, Agostinho

    2016-04-12

    The study of bioactive compounds from marine animals has provided, over time, an endless source of interesting molecules. Jellyfish are commonly targets of study due to their toxic proteins. However, there is a gap in reviewing successful wet-lab methods employed in these animals, which compromises the fast progress in the detection of related biomolecules. Here, we provide a compilation of the most effective wet-lab methodologies for jellyfish venom extraction prior to proteomic analysis-separation, identification and toxicity assays. This includes SDS-PAGE, 2DE, gel chromatography, HPLC, DEAE, LC-MS, MALDI, Western blot, hemolytic assay, antimicrobial assay and protease activity assay. For a more comprehensive approach, jellyfish toxicity studies should further consider transcriptome sequencing. We reviewed such methodologies and other genomic techniques used prior to the deep sequencing of transcripts, including RNA extraction, construction of cDNA libraries and RACE. Overall, we provide an overview of the most promising methods and their successful implementation for optimizing time and effort when studying jellyfish.

  12. Biogeochemical implications of decomposing jellyfish blooms in a changing climate

    NASA Astrophysics Data System (ADS)

    Chelsky, Ariella; Pitt, Kylie A.; Welsh, David T.

    2015-03-01

    Jellyfish often exhibit 'boom and bust' population dynamics whereby they proliferate rapidly and then die en masse and decompose. The few studies that have investigated post-bloom processes have not studied how changing ocean conditions will alter rates of decomposition. Climate change will result in warmer and more acidic waters, and studies therefore need to consider these factors in concert to determine their combined effect on decomposition processes. To quantify the effect, we measured oxygen consumption and nutrient regeneration rates during decomposition of Catostylus mosaicus in mesocosms at current average summer pH and temperature (pH 8.0 and 27 °C) as well as conditions projected for year 2100 (pH 7.8 and 30 °C) and compared these fluxes to control mesocosms without jellyfish over 12 days. We hypothesised that rates of jellyfish decomposition, as measured by oxygen demand and nutrient regeneration, would be accelerated in the end-of-century treatments, compared to present day treatments. Overall decomposition rates were only slightly elevated under end-of-century conditions, and the difference was only significant for ammonium fluxes from 19 h until 43 h after the experiment commenced. The difference between treatments was much smaller than would be expected due to the temperature increase, based on theoretical modelling of jellyfish decomposition which predicts a Q10 of 4.28, or a 1.5 fold increase in decomposition rates. This highlights the importance of investigating net effects on decomposition rates, as simultaneous shifts in temperature and pH may not follow patterns predicted due to one stressor alone. Ultimately, these results suggest that rates of oxygen consumption and nutrient regeneration resulting from collapsed jellyfish blooms may not change drastically over the next 100 years.

  13. Jellyfish (Cyanea nozakii) decomposition and its potential influence on marine environments studied via simulation experiments.

    PubMed

    Qu, Chang-Feng; Song, Jin-Ming; Li, Ning; Li, Xue-Gang; Yuan, Hua-Mao; Duan, Li-Qin; Ma, Qing-Xia

    2015-08-15

    A growing body of evidence suggests that the jellyfish population in Chinese seas is increasing, and decomposition of jellyfish strongly influences the marine ecosystem. This study investigated the change in water quality during Cyanea nozakii decomposition using simulation experiments. The results demonstrated that the amount of dissolved nutrients released by jellyfish was greater than the amount of particulate nutrients. NH4(+) was predominant in the dissolved matter, whereas the particulate matter was dominated by organic nitrogen and inorganic phosphorus. The high N/P ratios demonstrated that jellyfish decomposition may result in high nitrogen loads. The inorganic nutrients released by C. nozakii decomposition were important for primary production. Jellyfish decomposition caused decreases in the pH and oxygen consumption associated with acidification and hypoxia or anoxia; however, sediments partially mitigated the changes in the pH and oxygen. These results imply that jellyfish decomposition can result in potentially detrimental effects on marine environments.

  14. On the dynamics of jellyfish locomotion via 3D particle tracking velocimetry

    NASA Astrophysics Data System (ADS)

    Piper, Matthew; Kim, Jin-Tae; Chamorro, Leonardo P.

    2016-11-01

    The dynamics of jellyfish (Aurelia aurita) locomotion is experimentally studied via 3D particle tracking velocimetry. 3D locations of the bell tip are tracked over 1.5 cycles to describe the jellyfish path. Multiple positions of the jellyfish bell margin are initially tracked in 2D from four independent planes and individually projected in 3D based on the jellyfish path and geometrical properties of the setup. A cubic spline interpolation and the exponentially weighted moving average are used to estimate derived quantities, including velocity and acceleration of the jellyfish locomotion. We will discuss distinctive features of the jellyfish 3D motion at various swimming phases, and will provide insight on the 3D contraction and relaxation in terms of the locomotion, the steadiness of the bell margin eccentricity, and local Reynolds number based on the instantaneous mean diameter of the bell.

  15. Homicide-suicide in Victoria, Australia.

    PubMed

    Milroy, C M; Dratsas, M; Ranson, D L

    1997-12-01

    Thirty-nine incidents of homicide-suicide occurring in Victoria, Australia between 1985 and 1989 were examined. In 33 cases the assailants were men. The victims were spouses or women living in a de facto marriage. The majority of the victims were shot, and this was also the most frequent method of suicide. Breakdown in a relationship was the most frequent reason for killing. Mental illness of the assailant accounted for the killing in approximately 20% of cases. Physical ill health and financial stress were identified as important associative factors, particularly in the elderly. The pattern of homicide-suicide in Victoria is similar to that observed in other jurisdictions and represents an important and distinct subgroup of homicide.

  16. Pancam Peek into 'Victoria Crater' (Stereo)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Left-eye view of a stereo pair for PIA08776

    [figure removed for brevity, see original site] Right-eye view of a stereo pair for PIA08776

    A drive of about 60 meters (about 200 feet) on the 943rd Martian day, or sol, of Opportunity's exploration of Mars' Meridiani Planum region (Sept. 18, 2006) brought the NASA rover to within about 50 meters (about 160 feet) of the rim of 'Victoria Crater.' This crater has been the mission's long-term destination for the past 21 Earth months. Opportunity reached a location from which the cameras on top of the rover's mast could begin to see into the interior of Victoria. This stereo anaglyph was made from frames taken on sol 943 by the panoramic camera (Pancam) to offer a three-dimensional view when seen through red-blue glasses. It shows the upper portion of interior crater walls facing toward Opportunity from up to about 850 meters (half a mile) away. The amount of vertical relief visible at the top of the interior walls from this angle is about 15 meters (about 50 feet). The exposures were taken through a Pancam filter selecting wavelengths centered on 750 nanometers.

    Victoria Crater is about five times wider than 'Endurance Crater,' which Opportunity spent six months examining in 2004, and about 40 times wider than 'Eagle Crater,' where Opportunity first landed. The great lure of Victoria is the expectation that a thick stack of geological layers will be exposed in the crater walls, potentially several times the thickness that was previously studied at Endurance and therefore, potentially preserving several times the historical record.

  17. Hazardous thunderstorm intensification over Lake Victoria.

    PubMed

    Thiery, Wim; Davin, Edouard L; Seneviratne, Sonia I; Bedka, Kristopher; Lhermitte, Stef; van Lipzig, Nicole P M

    2016-09-23

    Weather extremes have harmful impacts on communities around Lake Victoria, where thousands of fishermen die every year because of intense night-time thunderstorms. Yet how these thunderstorms will evolve in a future warmer climate is still unknown. Here we show that Lake Victoria is projected to be a hotspot of future extreme precipitation intensification by using new satellite-based observations, a high-resolution climate projection for the African Great Lakes and coarser-scale ensemble projections. Land precipitation on the previous day exerts a control on night-time occurrence of extremes on the lake by enhancing atmospheric convergence (74%) and moisture availability (26%). The future increase in extremes over Lake Victoria is about twice as large relative to surrounding land under a high-emission scenario, as only over-lake moisture advection is high enough to sustain Clausius-Clapeyron scaling. Our results highlight a major hazard associated with climate change over East Africa and underline the need for high-resolution projections to assess local climate change.

  18. Hazardous thunderstorm intensification over Lake Victoria

    PubMed Central

    Thiery, Wim; Davin, Edouard L.; Seneviratne, Sonia I.; Bedka, Kristopher; Lhermitte, Stef; van Lipzig, Nicole P. M.

    2016-01-01

    Weather extremes have harmful impacts on communities around Lake Victoria, where thousands of fishermen die every year because of intense night-time thunderstorms. Yet how these thunderstorms will evolve in a future warmer climate is still unknown. Here we show that Lake Victoria is projected to be a hotspot of future extreme precipitation intensification by using new satellite-based observations, a high-resolution climate projection for the African Great Lakes and coarser-scale ensemble projections. Land precipitation on the previous day exerts a control on night-time occurrence of extremes on the lake by enhancing atmospheric convergence (74%) and moisture availability (26%). The future increase in extremes over Lake Victoria is about twice as large relative to surrounding land under a high-emission scenario, as only over-lake moisture advection is high enough to sustain Clausius–Clapeyron scaling. Our results highlight a major hazard associated with climate change over East Africa and underline the need for high-resolution projections to assess local climate change. PMID:27658848

  19. Opportunity Traverse Map, 'Eagle' to 'Victoria'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Annotated Image

    NASA's Mars Exploration Rover Opportunity reached the rim of 'Victoria Crater' on Sept. 27, 2006, during the 951st Martian day, or sol, of the rover's work in the Meridian Planum region of Mars. Opportunity drove 9.28 kilometers (5.77 miles) in the explorations that took it from 'Eagle Crater,' where it landed in January 2004, eastward to 'Endurance Crater,' which it investigated for about half of 2004, then southward to Victoria.

    This map of Opportunity's trek so far is overlaid onto images taken by the Mars Orbiter Camera on NASA's Mars Global Surveyor. Victoria is about 800 meters (one-half mile) in diameter, or about five times wider than Endurance and 40 times wider than Eagle. The scale bar at lower right shows the length of 800 meters (0.50 mile). North is up.

    The Martian sol dates in the annotated image are as follows: sol 58 was March 24, 2004 sol 315 was December 12, 2004 sol 446 was April 26, 2005 sol 654 was November 25, 2005 sol 833 was May 28, 2006 sol 898 was August 3, 2006 sol 952 was September 28, 2006

  20. Hazardous thunderstorm intensification over Lake Victoria

    NASA Astrophysics Data System (ADS)

    Thiery, Wim; Davin, Edouard L.; Seneviratne, Sonia I.; Bedka, Kristopher; Lhermitte, Stef; van Lipzig, Nicole P. M.

    2016-09-01

    Weather extremes have harmful impacts on communities around Lake Victoria, where thousands of fishermen die every year because of intense night-time thunderstorms. Yet how these thunderstorms will evolve in a future warmer climate is still unknown. Here we show that Lake Victoria is projected to be a hotspot of future extreme precipitation intensification by using new satellite-based observations, a high-resolution climate projection for the African Great Lakes and coarser-scale ensemble projections. Land precipitation on the previous day exerts a control on night-time occurrence of extremes on the lake by enhancing atmospheric convergence (74%) and moisture availability (26%). The future increase in extremes over Lake Victoria is about twice as large relative to surrounding land under a high-emission scenario, as only over-lake moisture advection is high enough to sustain Clausius-Clapeyron scaling. Our results highlight a major hazard associated with climate change over East Africa and underline the need for high-resolution projections to assess local climate change.

  1. Biomass of scyphozoan jellyfish, and its spatial association with 0-group fish in the Barents Sea.

    PubMed

    Eriksen, Elena; Prozorkevich, Dmitry; Trofimov, Aleksandr; Howell, Daniel

    2012-01-01

    An 0-group fish survey is conducted annually in the Barents Sea in order to estimate fish population abundance. Data on jellyfish by-catch have been recorded since 1980, although this dataset has never been analysed. In recent years, however, the ecological importance of jellyfish medusae has become widely recognized. In this paper the biomass of jellyfish (medusae) in 0-60 m depths is calculated for the period 1980-2010. During this period the climate changed from cold to warm, and changes in zooplankton and fish distribution and abundance were observed. This paper discusses the less well known ecosystem component; jellyfish medusae within the Phylum Cnidaria, and their spatial and temporal variation. The long term average was ca. 9×10⁸ kg, with some years showing biomasses in excess of 5×10⁹ kg. The biomasses were low during 1980s, increased during 1990s, and were highest in early 2000s with a subsequent decline. The bulk of the jellyfish were observed in the central parts of the Barents Sea, which is a core area for most 0-group fishes. Jellyfish were associated with haddock in the western area, with haddock and herring in the central and coastal area, and with capelin in the northern area of the Barents Sea. The jellyfish were present in the temperature interval 1°Cjellyfish occurring between 4.0-7.0°C. It seems that the ongoing warming trend may be favourable for Barents Sea jellyfish medusae; however their biomass has showed a recent moderate decline during years with record high temperatures in the Barents Sea. Jellyfish are undoubtedly an important component of the Barents Sea ecosystem, and the data presented here represent the best summary of jellyfish biomass and distribution yet published for the region.

  2. Cytochalasin derivatives from a jellyfish-derived fungus Phoma sp.

    PubMed

    Kim, Eun La; Wang, Haibo; Park, Ju Hee; Hong, Jongki; Choi, Jae Sue; Im, Dong Soon; Chung, Hae Young; Jung, Jee H

    2015-01-01

    Four new cytochalasin derivatives (1-4), together with proxiphomin (5), were isolated from a jellyfish-derived fungus Phoma sp. The planar structures and relative stereochemistry were established by analysis of 1D and 2D NMR data. The absolute configuration was defined by the modified Mosher's method. The compounds showed moderate cytotoxicity against a small panel of human solid tumor cell lines (A549, KB, and HCT116).

  3. Self-repairing symmetry in jellyfish through mechanically driven reorganization

    PubMed Central

    Abrams, Michael J.; Basinger, Ty; Yuan, William; Guo, Chin-Lin; Goentoro, Lea

    2015-01-01

    What happens when an animal is injured and loses important structures? Some animals simply heal the wound, whereas others are able to regenerate lost parts. In this study, we report a previously unidentified strategy of self-repair, where moon jellyfish respond to injuries by reorganizing existing parts, and rebuilding essential body symmetry, without regenerating what is lost. Specifically, in response to arm amputation, the young jellyfish of Aurelia aurita rearrange their remaining arms, recenter their manubria, and rebuild their muscular networks, all completed within 12 hours to 4 days. We call this process symmetrization. We find that symmetrization is not driven by external cues, cell proliferation, cell death, and proceeded even when foreign arms were grafted on. Instead, we find that forces generated by the muscular network are essential. Inhibiting pulsation using muscle relaxants completely, and reversibly, blocked symmetrization. Furthermore, we observed that decreasing pulse frequency using muscle relaxants slowed symmetrization, whereas increasing pulse frequency by lowering the magnesium concentration in seawater accelerated symmetrization. A mathematical model that describes the compressive forces from the muscle contraction, within the context of the elastic response from the mesoglea and the ephyra geometry, can recapitulate the recovery of global symmetry. Thus, self-repair in Aurelia proceeds through the reorganization of existing parts, and is driven by forces generated by its own propulsion machinery. We find evidence for symmetrization across species of jellyfish (Chrysaora pacifica, Mastigias sp., and Cotylorhiza tuberculata). PMID:26080418

  4. Jellyfish monitoring on coastlines using remote piloted aircraft

    NASA Astrophysics Data System (ADS)

    Barrado, C.; Fuentes, J. A.; Salamí, E.; Royo, P.; Olariaga, A. D.; López, J.; Fuentes, V. L.; Gili, J. M.; Pastor, E.

    2014-03-01

    In the last 10 years the number of jellyfish shoals that reach the swimming area of the Mediterranean Sea are increasing constantly. The term "Jellyfish" refers to animals from different taxonomic groups but the Scyphomedusae are within the most significant one. Four species of Scyphomedusae are the most conspicuous ones inhabiting the studied area, the Barcelona metropolitan area. Jellyfish are usually found at the surface waters, forming big swarms. This feature makes possible to detect them remotely, using a visual camera and image processing algorithms. In this paper we present the characteristics of a remote piloted aircraft capable to perform monitoring flights during the whole summer season. The requirements of the aircraft are to be easy to operate, to be able to flight at low altitude (100 m) following the buoy line (200 m from the beach line) and to be save for other users of the seaside. The remote piloted aircraft will carry a vision system and a processing board able to obtain useful information on real-time.

  5. Hemolytic venoms from marine cnidarian jellyfish – an overview

    PubMed Central

    Mariottini, Gian Luigi

    2014-01-01

    Cnidarian jellyfish are viewed as an emergent problem in several coastal zones throughout the world. Recurrent outbreaks pose a serious threat to tourists and bathers, as well as to sea-workers, involving health and economical aspects. As a rule, cnidarian stinging as a consequence of nematocyst firing induces merely local symptoms but cardiovascular or neurological complications can also occur. Hemolysis is a frequent effect of cnidarian stinging; this dangerous condition is known to be caused by several venoms and can sometimes be lethal. At present, the bulk of data concerning hemolytic cnidarian venoms comes from the study of benthic species, such as sea anemones and soft corals, but hemolytic factors were found in venoms of several siphonophore, cubozoan and scyphozoan jellyfish, which are mainly involved in the envenomation of bathers and sea-workers. Therefore, the aim of this paper is to review the scientific literature concerning the hemolytic venoms from cnidarian jellyfish taking into consideration their importance in human pathology as well as health implications and possible therapeutic measures. PMID:25386336

  6. Autonomic neurotoxicity of jellyfish and marine animal venoms.

    PubMed

    Burnett, J W; Weinrich, D; Williamson, J A; Fenner, P J; Lutz, L L; Bloom, D A

    1998-04-01

    Venoms and poisons of jellyfish and other marine animals can induce damage to the human nervous and circulatory systems. Clues to the pathogenesis and clinical manifestations of these lesions can be obtained from data of human envenomations and animal experimentation. Because many investigators are unaware that marine animal venoms have autonomic actions, this paper aims to elucidate the broad antagonistic or toxic effects these compounds have on the autonomic nervous system. Marine venoms can affect ion transport of particularly sodium and calcium, induce channels or pores in neural and muscular cellular membranes, alter intracellular membranes of organelles and release mediators of inflammation. The box jellyfish, particularly Chironex fleckeri, in the Indo-Pacific region, is the world's most venomous marine animal and is responsible for autonomic disorders in patients. The symptoms induced by these venoms are vasospasm, cardiac irregularities, peripheral neuropathy, aphonia, ophthalmic abnormalities and parasympathetic dysautonomia. Cases of Irukandji syndrome, caused by the jellyfish Carukia barnesi, have symptoms that mimic excessive catecholamine release. Coelenterate venoms can also target the myocardium, Purkinje fiber, A-V node or aortic ring. Actions on nerves, as well as skeletal, smooth or cardiac muscle occur. Recent studies indicate that the hepatic P-450 enzyme family may be injured by these compounds. The multiplicity of these venom activities means that a thorough understanding of the sting pathogenesis will be essential in devising effective therapies.

  7. Nucleotide sequences of 5S rRNAs from four jellyfishes.

    PubMed

    Hori, H; Ohama, T; Kumazaki, T; Osawa, S

    1982-11-25

    The nucleotide sequences of 5S rRNAs from four jellyfishes, Spirocodon saltatrix, Nemopsis dofleini, Aurelia aurita and Chrysaora quinquecirrha have been determined. The sequences are highly similar to each other. A fairly high similarity was also found between these jellyfishes and a sea anemone, Anthopleura japonica.

  8. The Bright Side of Gelatinous Blooms: Nutraceutical Value and Antioxidant Properties of Three Mediterranean Jellyfish (Scyphozoa)

    PubMed Central

    Leone, Antonella; Lecci, Raffaella Marina; Durante, Miriana; Meli, Federica; Piraino, Stefano

    2015-01-01

    Jellyfish are recorded with increasing frequency and magnitude in many coastal areas and several species display biological features comparable to the most popular Asiatic edible jellyfish. The biochemical and antioxidant properties of wild gelatinous biomasses, in terms of nutritional and nutraceutical values, are still largely unexplored. In this paper, three of the most abundant and commonly recorded jellyfish species (Aurelia sp.1, Cotylorhiza tuberculata and Rhizostoma pulmo) in the Mediterranean Sea were subject to investigation. A sequential enzymatic hydrolysis of jellyfish proteins was set up by pepsin and collagenase treatments of jellyfish samples after aqueous or hydroalcoholic protein extraction. The content and composition of proteins, amino acids, phenolics, and fatty acids of the three species were recorded and compared. Protein content (mainly represented by collagen) up to 40% of jellyfish dry weight were found in two of the three jellyfish species (C. tuberculata and R. pulmo), whereas the presence of ω-3 and ω-6 polyunsaturated fatty acids (PUFAs) was significantly higher in the zooxanthellate jellyfish C. tuberculata only. Remarkable antioxidant ability was also recorded from both proteinaceous and non proteinaceous extracts and the hydrolyzed protein fractions in all the three species. The abundance of collagen, peptides and other bioactive molecules make these Mediterranean gelatinous biomasses a largely untapped source of natural compounds of nutraceutical, cosmeceutical and pharmacological interest. PMID:26230703

  9. Jellyfish as vectors of bacterial disease for farmed salmon (Salmo salar).

    PubMed

    Ferguson, Hugh W; Delannoy, Christian M J; Hay, Stephen; Nicolson, James; Sutherland, David; Crumlish, Margaret

    2010-05-01

    Swarms or blooms of jellyfish are increasingly problematic and can result in high mortality rates of farmed fish. Small species of jellyfish, such as Phialella quadrata (13 mm in diameter), are capable of passing through the mesh of sea cages and being sucked into the mouth of fish during respiration. Results of the current study show that the initial damage to gills of farmed Atlantic salmon, likely produced by nematocyst-derived toxins from the jellyfish, was compounded by secondary bacterial infection with Tenacibaculum maritimum. Results also demonstrate that these filamentous bacteria were present on the mouth of the jellyfish and that their DNA sequences were almost identical to those of bacteria present on the salmon gills. This suggests that the bacterial lesions were not the result of an opportunistic infection of damaged tissue, as previously thought. Instead, P. quadrata is probably acting as a vector for this particular bacterial pathogen, and it is the first time that evidence to support such a link has been presented. No prior literature describing the presence of bacteria associated with jellyfish, except studies about their decay, could be found. It is not known if all jellyfish of this and other species carry similar bacteria or the relationship to each other. Their source, the role they play under other circumstances, and indeed whether the jellyfish were themselves diseased are also not known. The high proteolytic capabilities of T. maritimum mean that partially digested gill tissues were readily available to the jellyfish, which rely heavily on intracellular digestion for their nutrition.

  10. The Bright Side of Gelatinous Blooms: Nutraceutical Value and Antioxidant Properties of Three Mediterranean Jellyfish (Scyphozoa).

    PubMed

    Leone, Antonella; Lecci, Raffaella Marina; Durante, Miriana; Meli, Federica; Piraino, Stefano

    2015-07-29

    Jellyfish are recorded with increasing frequency and magnitude in many coastal areas and several species display biological features comparable to the most popular Asiatic edible jellyfish. The biochemical and antioxidant properties of wild gelatinous biomasses, in terms of nutritional and nutraceutical values, are still largely unexplored. In this paper, three of the most abundant and commonly recorded jellyfish species (Aurelia sp.1, Cotylorhiza tuberculata and Rhizostoma pulmo) in the Mediterranean Sea were subject to investigation. A sequential enzymatic hydrolysis of jellyfish proteins was set up by pepsin and collagenase treatments of jellyfish samples after aqueous or hydroalcoholic protein extraction. The content and composition of proteins, amino acids, phenolics, and fatty acids of the three species were recorded and compared. Protein content (mainly represented by collagen) up to 40% of jellyfish dry weight were found in two of the three jellyfish species (C. tuberculata and R. pulmo), whereas the presence of ω-3 and ω-6 polyunsaturated fatty acids (PUFAs) was significantly higher in the zooxanthellate jellyfish C. tuberculata only. Remarkable antioxidant ability was also recorded from both proteinaceous and non proteinaceous extracts and the hydrolyzed protein fractions in all the three species. The abundance of collagen, peptides and other bioactive molecules make these Mediterranean gelatinous biomasses a largely untapped source of natural compounds of nutraceutical, cosmeceutical and pharmacological interest.

  11. Modeling jellyfish Pelagia noctiluca transport and stranding in the Ligurian Sea.

    PubMed

    Berline, L; Zakardjian, B; Molcard, A; Ourmières, Y; Guihou, K

    2013-05-15

    Jellyfish blooms are generally attributed to a biological response to the environment, neglecting the role of transport patterns in redistributing existing populations. Here, we use high-resolution (1.25km) ocean modeling to examine the role of transport in the onshore arrival and abundance of the pelagic stinging jellyfish Pelagia noctiluca on the Ligurian Sea coast. Jellyfish are modeled as Lagrangian particles with a 0-300-m diel vertical migration typical of P. noctiluca. Over the course of a year, onshore arrivals are not restricted to the summer. Arrivals are concentrated at capes, but abundance can reach maxima in bays and in the lee of capes. Two factors impact jellyfish arrivals at the coast: the position of the Northern Current and the wind. A comparison of summer 2006 and available onshore jellyfish observations suggests a correct capture of the main stranding events by the model. These results have implications for understanding long-term fluctuations.

  12. THE NEWARK VICTORIA PLAN, A REPORT TO THE VICTORIA FOUNDATION ON THE STATUS OF THE PLAN.

    ERIC Educational Resources Information Center

    FRIEDRICHS, ROBERT W.; AND OTHERS

    THIS EVALUATION IS CONCERNED WITH THE FIRST YEAR OF IMPLEMENTATION OF THE VICTORIA PLAN IN A NEWARK, N.J., ELEMENTARY SCHOOL. THE COMPONENTS OF THIS IMPROVEMENT PROGRAM WHICH ARE DISCUSSED ARE CLASS TRIPS AND ASSEMBLIES, THE ROLE OF THE TEACHER, THE NURSERY SCHOOL, AND MATERIALS AND SUPPLIES. MOST OF THE EVALUATION IS DEVOTED TO THE PROBLEMS WHICH…

  13. 'Victoria Crater' from 'Duck Bay' (Polar Projection)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA's Mars rover Opportunity edged 3.7 meters (12 feet) closer to the top of the 'Duck Bay' alcove along the rim of 'Victoria Crater' during the rover's 952nd Martian day, or sol (overnight Sept. 27 to Sept. 28), and gained this vista of the crater. The rover's navigation camera took the seven exposures combined into this mosaic view of the crater's interior. This crater has been the mission's long-term destination for the past 21 Earth months.

    The far side of the crater is about 800 meters (one-half mile) away. The rim of the crater is composed of alternating promontories, rocky points towering approximately 70 meters (230 feet) above the crater floor, and recessed alcoves, such as Duck Bay. The bottom of the crater is covered by sand that has been shaped into ripples by the Martian wind. The rocky cliffs in the foreground have been informally named 'Cape Verde,' on the left, and 'Cabo Frio,' on the right.

    Victoria Crater is about five times wider than 'Endurance Crater,' which Opportunity spent six months examining in 2004, and about 40 times wider than 'Eagle Crater,' where Opportunity first landed. The great lure of Victoria is an expectation that the thick stack of geological layers exposed in the crater walls could reveal the record of past environmental conditions over a much greater span of time than Opportunity has read from rocks examined earlier in the mission.

    This view is presented as a polar projection with geometric seam correction.

  14. 'Victoria Crater' from 'Duck Bay' (Vertical Projection)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA's Mars rover Opportunity edged 3.7 meters (12 feet) closer to the top of the 'Duck Bay' alcove along the rim of 'Victoria Crater' during the rover's 952nd Martian day, or sol (overnight Sept. 27 to Sept. 28), and gained this vista of the crater. The rover's navigation camera took the seven exposures combined into this mosaic view of the crater's interior. This crater has been the mission's long-term destination for the past 21 Earth months.

    The far side of the crater is about 800 meters (one-half mile) away. The rim of the crater is composed of alternating promontories, rocky points towering approximately 70 meters (230 feet) above the crater floor, and recessed alcoves, such as Duck Bay. The bottom of the crater is covered by sand that has been shaped into ripples by the Martian wind. The rocky cliffs in the foreground have been informally named 'Cape Verde,' on the left, and 'Cabo Frio,' on the right.

    Victoria Crater is about five times wider than 'Endurance Crater,' which Opportunity spent six months examining in 2004, and about 40 times wider than 'Eagle Crater,' where Opportunity first landed. The great lure of Victoria is an expectation that the thick stack of geological layers exposed in the crater walls could reveal the record of past environmental conditions over a much greater span of time than Opportunity has read from rocks examined earlier in the mission.

    This view is presented as a vertical projection with geometric seam correction.

  15. 'Victoria Crater' from 'Duck Bay' (Stereo)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Figure 1

    [figure removed for brevity, see original site] Figure 2

    NASA's Mars rover Opportunity edged 3.7 meters (12 feet) closer to the top of the 'Duck Bay' alcove along the rim of 'Victoria Crater' during the rover's 952nd Martian day, or sol (overnight Sept. 27 to Sept. 28), and gained this vista of the crater. The rover's navigation camera took the seven exposures combined into this mosaic view of the crater's interior. This crater has been the mission's long-term destination for the past 21 Earth months.

    The far side of the crater is about 800 meters (one-half mile) away. The rim of the crater is composed of alternating promontories, rocky points towering approximately 70 meters (230 feet) above the crater floor, and recessed alcoves, such as Duck Bay. The bottom of the crater is covered by sand that has been shaped into ripples by the Martian wind. The rocky cliffs in the foreground have been informally named 'Cape Verde,' on the left, and 'Cabo Frio,' on the right.

    Victoria Crater is about five times wider than 'Endurance Crater,' which Opportunity spent six months examining in 2004, and about 40 times wider than 'Eagle Crater,' where Opportunity first landed. The great lure of Victoria is an expectation that the thick stack of geological layers exposed in the crater walls could reveal the record of past environmental conditions over a much greater span of time than Opportunity has read from rocks examined earlier in the mission.

    The stereo-anaglyph view presented here is a cylindrical projection with geometric seam correction.

  16. 'Victoria' After Sol 950 Drive (Stereo)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Left-eye view of a stereo pair for PIA08778

    [figure removed for brevity, see original site] Right-eye view of a stereo pair for PIA08778 [figure removed for brevity, see original site] Cylindrical view for PIA08778

    A drive of about 30 meters (about 100 feet) on the 950th Martian day, or sol, of Opportunity's exploration of Mars' Meridiani Planum region (Sept. 25, 2006) brought the NASA rover to within about 20 meters (about 66 feet) of the rim of 'Victoria Crater.' From that position, the rover's navigation camera took the exposures combined into this stereo anaglyph, which appears three-dimensional when viewed through red-green glasses. The scalloped shape of the crater is visible on the left edge. Due to a small dune or ripple close to the nearest part of the rim, the scientists and engineers on the rover team planned on sol 951 to drive to the right of the ripple, but not quite all the way to the rim, then to proceed to the rim the following sol. The image is presented in cylindrical projection with geometric seam correction.

    Victoria Crater is about 800 meters (one-half mile) in diameter, about five times wider than 'Endurance Crater,' which Opportunity spent six months examining in 2004, and about 40 times wider than 'Eagle Crater,' where Opportunity first landed. The great lure of Victoria is the expectation that a thick stack of geological layers will be exposed in the crater walls, potentially several times the thickness that was previously studied at Endurance and therefore, potentially preserving several times the historical record.

  17. Inside Victoria Crater for Extended Exploration

    NASA Technical Reports Server (NTRS)

    2007-01-01

    After a finishing an in-and-out maneuver to check wheel slippage near the rim of Victoria Crater, NASA's Mars Exploration Rover Opportunity re-entered the crater during the rover's 1,293rd Martian day, or sol, (Sept. 13, 2007) to begin a weeks-long exploration of the inner slope.

    Opportunity's front hazard-identification camera recorded this wide-angle view looking down into and across the crater at the end of the day's drive. The rover's position was about six meters (20 feet) inside the rim, in the 'Duck Bay' alcove of the crater.

  18. Uranium mineralization in southern Victoria Land, Antarctica

    SciTech Connect

    Dreschhoff, G.A.M.; Zeller, E.J.

    1986-01-01

    For the past 10 antarctic field seasons, an airborne gamma-ray spectrometric survey has been conducted over widely separated parts of the continent. Localized accumulations of both primary and secondary uranium minerals have been discovered at several localities scattered along the Transantarctic Mountains from the Scott Glacier to northern Victoria Land. A number of highly significant radiation anomalies have been discovered in the area between the Koettlitz Glacier and the Pyramid Trough. The occurrences consist of pegmatite vein complexes which contain an association of primary uranium and thorium minerals. Of still greater significance is the fact that abundant secondary uranium minerals were found in association with the primary deposits, and they indicate clearly that uranium is geochemically mobile under the conditions imposed by the arid polar climate that now exists in southern Victoria Land. Preliminary results of a uranium analysis performed by neutron activation indicate a concentration of 0.12% uranium in a composite sample from the two veins. Even higher levels of thorium are present. The nature of the primary uranium mineralization is currently under investigation. Preliminary results are discussed.

  19. At Bright Band Inside Victoria Crater

    NASA Technical Reports Server (NTRS)

    2007-01-01

    A layer of light-toned rock exposed inside Victoria Crater in the Meridiani Planum region of Mars appears to mark where the surface was at the time, many millions of years ago, when an impact excavated the crater. NASA's Mars Exploration Rover Opportunity drove to this bright band as the science team's first destination for the rover during investigations inside the crater.

    Opportunity's left front hazard-identification camera took this image just after the rover finished a drive of 2.25 meters (7 feet, 5 inches) during the rover's 1,305th Martian day, or sol, (Sept. 25, 2007). The rocks beneath the rover and its extended robotic arm are part of the bright band.

    Victoria Crater has a scalloped shape of alternating alcoves and promontories around the crater's circumference. Opportunity descended into the crater two weeks earlier, within an alcove called 'Duck Bay.' Counterclockwise around the rim, just to the right of the arm in this image, is a promontory called 'Cabo Frio.'

  20. On the Rim of 'Victoria Crater'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA's Mars rover Opportunity reached the rim of 'Victoria Crater' in Mars' Meridiani Planum region with a 26-meter (85-foot) drive during the rover's 951st Martian day, or sol (Sept. 26, 2006). After the drive, the rover's navigation camera took the three exposures combined into this view of the crater's interior. This crater has been the mission's long-term destination for the past 21 Earth months.

    A half mile in the distance one can see about 20 percent of the far side of the crater framed by the rocky cliffs in the foreground to the left and right of the image. The rim of the crater is composed of alternating promontories, rocky points towering approximately 70 meters (230 feet) above the crater floor, and recessed alcoves. The bottom of the crater is covered by sand that has been shaped into ripples by the Martian wind.

    The position at the end of the sol 951 drive is about six meters from the lip of an alcove called 'Duck Bay.' The rover team planned a drive for sol 952 that would move a few more meters forward, plus more imaging of the near and far walls of the crater.

    Victoria Crater is about five times wider than 'Endurance Crater,' which Opportunity spent six months examining in 2004, and about 40 times wider than 'Eagle Crater,' where Opportunity first landed.

    This view is presented as a cylindrical projection with geometric seam correction.

  1. Degradation of Victoria Crater, Meridiani Planum, Mars

    NASA Astrophysics Data System (ADS)

    Grant, J. A.; Wilson, S. A.; Cohen, B. A.; Golombek, M. P.; Geissler, P. E.; Sullivan, R. J.

    2007-12-01

    Victoria crater (2.05N, 354.51E) is ~750 m in diameter and the largest crater on Mars observed in situ. The Mars Exploration Rover Opportunity traversed NW to SE across a broad annulus dominated by dark sand that at least partially surrounds the crater before navigating the northern crater rim. Rover observations of the crater and ejecta deposits are complemented by images with 26-52 cm/pixel scales from the High Resolution Imaging Science Experiment (HiRISE) on Mars Reconnaissance Orbiter and enable assessment of degradation state. The present depth/diameter ratio for Victoria is 0.1, less than the 0.2 expected for a pristine primary impact structure. Together with the eroded, serrated rim, this implies an originally smaller crater diameter and/or considerable infilling consistent with occurrence of a large dune field and few exposed rocks on the crater floor. The height and width of the raised rim is generally 4-5 m and 150-225 m, respectively, less than the 30 m and 500-600 m, respectively, expected for a pristine 750 m diameter crater. Ejecta thicknesses around the rim were derived using rover-based and HiRISE images and yield consistent estimates averaging ~3 m. The serrated rim plan creates a series of promontories extending up to 50 m into the crater and generally fronted by 30-60 degree slopes that are locally vertical and are separated by bays whose floors typically slope 15-25 degrees. A crater originally on order of 600-650 m in diameter and subsequently enlarged by mass wasting and aeolian erosion may yield a structure resembling Victoria today. The steep expression of the promontories and local outcroppings of rocks in the ejecta blanket points to some ongoing mass wasting, but the relative paucity of associated flanking talus indicates derived blocks of sulfate sandstone are not resistant to saltating sand and are rapidly broken down by the wind or are completely covered/filled in by aeolian drift. At Cape St. Vincent, the promontory appears undercut

  2. Impact of Stinging Jellyfish Proliferations along South Italian Coasts: Human Health Hazards, Treatment and Social Costs

    PubMed Central

    De Donno, Antonella; Idolo, Adele; Bagordo, Francesco; Grassi, Tiziana; Leomanni, Alessandro; Serio, Francesca; Guido, Marcello; Canitano, Mariarita; Zampardi, Serena; Boero, Ferdinando; Piraino, Stefano

    2014-01-01

    Stinging jellyfish outbreaks represent a health hazard, causing contact dermatitis and systemic reactions. This study investigated the epidemiology, severity, and treatment protocols of jellyfish stings in a coastal area with high tourist development and frequent stinging jellyfish outbreaks of the central Mediterranean (Salento, Southern Italy), and the associated costs for the Italian National Health Service. In 2007–2011, 1,733 bathers (mostly children and females) sought medical assistance following jellyfish stings, the main cause of human pathologies due to contact with marine organisms. The majority of events were reported in the years 2007–2009, whereas the occurrence of cnidarian jellyfish outbreaks has been increasingly reported in the same area since summer 2010. Most symptoms were limited to local and cutaneous reactions; conversely, 8.7% of cases evoked complications, mainly due to allergic reactions. The main drugs used were corticosteroids, locally applied and systemic (46% and 43%, respectively), and with ammonia (74%) as the main non-pharmacological treatment. The estimated cost of jellyfish-related first-aid services along the Salento coastline over the 5-year period was approximately 400,000 Euros. Therefore the management of jellyfish outbreak phenomena need coordinated research efforts towards a better understanding of underlying ecological mechanisms, together with the adoption of effective prevention policy, mitigation strategies, and appropriate planning of health services at tourist hot spots. PMID:24583831

  3. Evaluation of the effects of various chemicals on discharge of and pain caused by jellyfish nematocysts.

    PubMed

    Birsa, Laura M; Verity, Peter G; Lee, Richard F

    2010-05-01

    Jellyfish tentacles in contact with human skin can produce pain swelling and redness. The pain is due to discharge of jellyfish nematocysts and associated toxins and discharge can be caused by a variety of mechanical and chemical stimuli. A series of tests were carried out with chemicals traditionally used to treat jellyfish stings e.g. acetic acid ammonia meat tenderizer baking soda and urea to determine if these chemicals stimulated or inhibited nematocyst discharge and if they brought relief to testers who were exposed to jellyfish tentacles. Chrysaora quinquecirrha (sea nettle) Chiropsalmus quadrumanus (sea wasp) and Physalia physalis (Portuguese man-of-war) were used in the study. It was found that many of the chemicals traditionally used to treat jellyfish stings stimulated nematocyst discharge and did not relieve the pain. However there was immediate relief when a common anesthetic lidocaine was sprayed on the skin of testers in contact with jellyfish tentacles. Initial exposure of tentacle suspensions to lidocaine prevented the nematocyst discharge by subsequent exposure to acetic acid ethanol ammonia or bromelain. Thus lidocaine in addition to acting as an anesthetic on skin in contact with jellyfish tentacles inhibited nematocyst discharge possibly by blocking sodium and/or calcium channels of the nematocytes.

  4. Nutritional composition and total collagen content of three commercially important edible jellyfish.

    PubMed

    Khong, Nicholas M H; Yusoff, Fatimah Md; Jamilah, B; Basri, Mahiran; Maznah, I; Chan, Kim Wei; Nishikawa, Jun

    2016-04-01

    The study aimed to evaluate nutraceutical potential of three commercially significant edible jellyfish species (Acromitus hardenbergi, Rhopilema hispidum and Rhopilema esculentum). The bell and oral arms of these jellyfishes were analyzed for their proximate composition, calorific value, collagen content, amino acid profile, chemical score and elemental constituent. In general, all jellyfish possessed low calorific values (1.0-4.9 kcal/g D.W.) and negligible fat contents (0.4-1.8 g/100 g D.W.), while protein (20.0-53.9 g/100 g D.W.) and minerals (15.9-57.2g/100g D.W.) were found to be the richest components. Total collagen content of edible jellyfish varied from 122.64 to 693.92 mg/g D.W., accounting for approximately half its total protein content. The dominant amino acids in both bell and oral arms of all jellyfish studied includes glycine, glutamate, threonine, proline, aspartate and arginine, while the major elements were sodium, potassium, chlorine, magnesium, sulfur, zinc and silicon. Among the jellyfish, A. hardenbergi exhibited significantly higher total amino acids, chemical scores and collagen content (p<0.05) compared to R. hispidum and R. esculentum. Having good protein quality and low calories, edible jellyfish is an appealing source of nutritive ingredients for the development of oral formulations, nutricosmetics and functional food.

  5. Impact of stinging jellyfish proliferations along south Italian coasts: human health hazards, treatment and social costs.

    PubMed

    De Donno, Antonella; Idolo, Adele; Bagordo, Francesco; Grassi, Tiziana; Leomanni, Alessandro; Serio, Francesca; Guido, Marcello; Canitano, Mariarita; Zampardi, Serena; Boero, Ferdinando; Piraino, Stefano

    2014-02-27

    Stinging jellyfish outbreaks represent a health hazard, causing contact dermatitis and systemic reactions. This study investigated the epidemiology, severity, and treatment protocols of jellyfish stings in a coastal area with high tourist development and frequent stinging jellyfish outbreaks of the central Mediterranean (Salento, Southern Italy), and the associated costs for the Italian National Health Service. In 2007-2011, 1,733 bathers (mostly children and females) sought medical assistance following jellyfish stings, the main cause of human pathologies due to contact with marine organisms. The majority of events were reported in the years 2007-2009, whereas the occurrence of cnidarian jellyfish outbreaks has been increasingly reported in the same area since summer 2010. Most symptoms were limited to local and cutaneous reactions; conversely, 8.7% of cases evoked complications, mainly due to allergic reactions. The main drugs used were corticosteroids, locally applied and systemic (46% and 43%, respectively), and with ammonia (74%) as the main non-pharmacological treatment. The estimated cost of jellyfish-related first-aid services along the Salento coastline over the 5-year period was approximately 400,000 Euros. Therefore the management of jellyfish outbreak phenomena need coordinated research efforts towards a better understanding of underlying ecological mechanisms, together with the adoption of effective prevention policy, mitigation strategies, and appropriate planning of health services at tourist hot spots.

  6. Deterministic Factors Overwhelm Stochastic Environmental Fluctuations as Drivers of Jellyfish Outbreaks

    PubMed Central

    Benedetti-Cecchi, Lisandro; Canepa, Antonio; Fuentes, Veronica; Tamburello, Laura; Purcell, Jennifer E.; Piraino, Stefano; Roberts, Jason; Boero, Ferdinando; Halpin, Patrick

    2015-01-01

    Jellyfish outbreaks are increasingly viewed as a deterministic response to escalating levels of environmental degradation and climate extremes. However, a comprehensive understanding of the influence of deterministic drivers and stochastic environmental variations favouring population renewal processes has remained elusive. This study quantifies the deterministic and stochastic components of environmental change that lead to outbreaks of the jellyfish Pelagia noctiluca in the Mediterranen Sea. Using data of jellyfish abundance collected at 241 sites along the Catalan coast from 2007 to 2010 we: (1) tested hypotheses about the influence of time-varying and spatial predictors of jellyfish outbreaks; (2) evaluated the relative importance of stochastic vs. deterministic forcing of outbreaks through the environmental bootstrap method; and (3) quantified return times of extreme events. Outbreaks were common in May and June and less likely in other summer months, which resulted in a negative relationship between outbreaks and SST. Cross- and along-shore advection by geostrophic flow were important concentrating forces of jellyfish, but most outbreaks occurred in the proximity of two canyons in the northern part of the study area. This result supported the recent hypothesis that canyons can funnel P. noctiluca blooms towards shore during upwelling. This can be a general, yet unappreciated mechanism leading to outbreaks of holoplanktonic jellyfish species. The environmental bootstrap indicated that stochastic environmental fluctuations have negligible effects on return times of outbreaks. Our analysis emphasized the importance of deterministic processes leading to jellyfish outbreaks compared to the stochastic component of environmental variation. A better understanding of how environmental drivers affect demographic and population processes in jellyfish species will increase the ability to anticipate jellyfish outbreaks in the future. PMID:26485278

  7. Deterministic Factors Overwhelm Stochastic Environmental Fluctuations as Drivers of Jellyfish Outbreaks.

    PubMed

    Benedetti-Cecchi, Lisandro; Canepa, Antonio; Fuentes, Veronica; Tamburello, Laura; Purcell, Jennifer E; Piraino, Stefano; Roberts, Jason; Boero, Ferdinando; Halpin, Patrick

    2015-01-01

    Jellyfish outbreaks are increasingly viewed as a deterministic response to escalating levels of environmental degradation and climate extremes. However, a comprehensive understanding of the influence of deterministic drivers and stochastic environmental variations favouring population renewal processes has remained elusive. This study quantifies the deterministic and stochastic components of environmental change that lead to outbreaks of the jellyfish Pelagia noctiluca in the Mediterranen Sea. Using data of jellyfish abundance collected at 241 sites along the Catalan coast from 2007 to 2010 we: (1) tested hypotheses about the influence of time-varying and spatial predictors of jellyfish outbreaks; (2) evaluated the relative importance of stochastic vs. deterministic forcing of outbreaks through the environmental bootstrap method; and (3) quantified return times of extreme events. Outbreaks were common in May and June and less likely in other summer months, which resulted in a negative relationship between outbreaks and SST. Cross- and along-shore advection by geostrophic flow were important concentrating forces of jellyfish, but most outbreaks occurred in the proximity of two canyons in the northern part of the study area. This result supported the recent hypothesis that canyons can funnel P. noctiluca blooms towards shore during upwelling. This can be a general, yet unappreciated mechanism leading to outbreaks of holoplanktonic jellyfish species. The environmental bootstrap indicated that stochastic environmental fluctuations have negligible effects on return times of outbreaks. Our analysis emphasized the importance of deterministic processes leading to jellyfish outbreaks compared to the stochastic component of environmental variation. A better understanding of how environmental drivers affect demographic and population processes in jellyfish species will increase the ability to anticipate jellyfish outbreaks in the future.

  8. Prokaryotic Abundance and Activity in Permafrost of the Northern Victoria Land and Upper Victoria Valley (Antarctica).

    PubMed

    La Ferla, Rosabruna; Azzaro, Maurizio; Michaud, Luigi; Caruso, Gabriella; Lo Giudice, Angelina; Paranhos, Rodolfo; Cabral, Anderson S; Conte, Antonella; Cosenza, Alessandro; Maimone, Giovanna; Papale, Maria; Rappazzo, Alessandro Ciro; Guglielmin, Mauro

    2017-03-13

    Victoria Land permafrost harbours a potentially large pool of cold-affected microorganisms whose metabolic potential still remains underestimated. Three cores (BC-1, BC-2 and BC-3) drilled at different depths in Boulder Clay (Northern Victoria Land) and one sample (DY) collected from a core in the Dry Valleys (Upper Victoria Valley) were analysed to assess the prokaryotic abundance, viability, physiological profiles and potential metabolic rates. The cores drilled at Boulder Clay were a template of different ecological conditions (different temperature regime, ice content, exchanges with atmosphere and with liquid water) in the same small basin while the Dry Valleys site was very similar to BC-2 conditions but with a complete different geological history and ground ice type. Image analysis was adopted to determine cell abundance, size and shape as well as to quantify the potential viable and respiring cells by live/dead and 5-cyano-2,3-ditolyl-tetrazolium chloride staining, respectively. Subpopulation recognition by apparent nucleic acid contents was obtained by flow cytometry. Moreover, the physiological profiles at community level by Biolog-Ecoplate™ as well as the ectoenzymatic potential rates on proteinaceous (leucine-aminopeptidase) and glucidic (ß-glucosidase) organic matter and on organic phosphates (alkaline-phosphatase) by fluorogenic substrates were tested. The adopted methodological approach gave useful information regarding viability and metabolic performances of microbial community in permafrost. The occurrence of a multifaceted prokaryotic community in the Victoria Land permafrost and a large number of potentially viable and respiring cells (in the order of 10(4)-10(5)) were recognised. Subpopulations with a different apparent DNA content within the different samples were observed. The physiological profiles stressed various potential metabolic pathways among the samples and intense utilisation rates of polymeric carbon compounds and carbohydrates

  9. The Bands Culture in Victoria, Australia: Live Music Benefits Career Paths, Employment and Community

    ERIC Educational Resources Information Center

    Watson, Amanda; Forrest, David

    2012-01-01

    This study explores the career paths, employment, business opportunities and community contributions made available through the provision and development of the contemporary performance bands' culture in the State of Victoria. It is framed with the support given to live music performers by Arts Victoria, Small Business Victoria and Music Victoria.…

  10. Forty Meters from Entry to Victoria Crater

    NASA Technical Reports Server (NTRS)

    2007-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera during the rover's 1,278th Martian day, or sol, (Aug. 28, 2007) to take the images combined into this view. The rover was perched at the lip of Victoria Crater, which is about 800 meters (one-half mile) in diameter.

    After assessment of possible routes for Opportunity to descend into the crater, the rover team selected a site farther to the right along the rim. That selected entry point lies near the ripple of bright soil visible just outside the crater near the top center of this scene. The driving distance for Opportunity from the Sol 1,278 viewpoint to the selected entry point is about 40 meters (about 130 feet).

    This view is presented as a cylindrical projection with geometric seam correction.

  11. Layers of 'Cape Verde' in 'Victoria Crater'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This view of Victoria crater is looking north from 'Duck Bay' towards the dramatic promontory called 'Cape Verde.' The dramatic cliff of layered rocks is about 50 meters (about 165 feet) away from the rover and is about 6 meters (about 20 feet) tall. The taller promontory beyond that is about 100 meters (about 325 feet) away, and the vista beyond that extends away for more than 400 meters (about 1300 feet) into the distance. This is an approximately true color rendering of images taken by the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity during the rover's 952nd sol, or Martian day, (Sept. 28, 2006) using the camera's 750-nanometer, 530-nanometer and 430-nanometer filters.

  12. Layers of 'Cabo Frio' in 'Victoria Crater'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This view of 'Victoria crater' is looking southeast from 'Duck Bay' towards the dramatic promontory called 'Cabo Frio.' The small crater in the right foreground, informally known as 'Sputnik,' is about 20 meters (about 65 feet) away from the rover, the tip of the spectacular, layered, Cabo Frio promontory itself is about 200 meters (about 650 feet) away from the rover, and the exposed rock layers are about 15 meters (about 50 feet) tall. This is an approximately true color rendering of images taken by the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity during the rover's 952nd sol, or Martian day, (Sept. 28, 2006) using the camera's 750-nanometer, 530-nanometer and 430-nanometer filters.

  13. Satellite View of Opportunity's Journey around 'Victoria Crater'

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Three years after embarking on a historic exploration of the red planet and six miles away from its landing site, NASA's Mars Exploration Rover Opportunity is traversing 'Victoria Crater' ridge by ridge, peering at layered cliffs in the interior. To identify various alcoves and cliffs along the way, science team members are using names of places visited by the 16th-century Earth explorer Ferdinand Magellan and his crew aboard the ship Victoria, who proved the Earth is round. (All names are unofficial unless approved by the International Astronomical Union.) This orbital view of 'Victoria Crater' was taken by NASA's Mars Reconnaissance Orbiter.

  14. Space Radar Image of Victoria, Canada

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This three-frequency spaceborne radar image shows the southern end of Vancouver Island on the west coast of Canada. The white area in the lower right is the city of Victoria, the capital of the province of British Columbia. The three radar frequencies help to distinguish different land use patterns. The bright pink areas are suburban regions, the brownish areas are forested regions, and blue areas are agricultural fields or forest clear-cuts. Founded in 1843 as a fur trading post, Victoria has grown to become one of western Canada's largest commercial centers. In the upper right is San Juan Island, in the state of Washington. The Canada/U.S. border runs through Haro Strait, on the right side of the image, between San Juan Island and Vancouver Island. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) on October 6, 1994, onboard the space shuttle Endeavour. The area shown is 37 kilometers by 42 kilometers (23 miles by 26 miles) and is centered at 48.5 degrees north latitude, 123.3 degrees west longitude. North is toward the upper left. The colors are assigned to different radar frequencies and polarizations as follows: red is L-band horizontally transmitted and received; green is C-band, vertically transmitted and received; and blue is X-band, vertically transmitted and received. SIR-C/X-SAR, a joint mission of the German, Italian and United States space agencies, is part of NASA's Mission to Planet Earth program.

  15. 'Lyell' Panorama inside Victoria Crater (Stereo)

    NASA Technical Reports Server (NTRS)

    2008-01-01

    During four months prior to the fourth anniversary of its landing on Mars, NASA's Mars Exploration Rover Opportunity examined rocks inside an alcove called 'Duck Bay' in the western portion of Victoria Crater. The main body of the crater appears in the upper right of this stereo panorama, with the far side of the crater lying about 800 meters (half a mile) away. Bracketing that part of the view are two promontories on the crater's rim at either side of Duck Bay. They are 'Cape Verde,' about 6 meters (20 feet) tall, on the left, and 'Cabo Frio,' about 15 meters (50 feet) tall, on the right. The rest of the image, other than sky and portions of the rover, is ground within Duck Bay.

    Opportunity's targets of study during the last quarter of 2007 were rock layers within a band exposed around the interior of the crater, about 6 meters (20 feet) from the rim. Bright rocks within the band are visible in the foreground of the panorama. The rover science team assigned informal names to three subdivisions of the band: 'Steno,' 'Smith,' and 'Lyell.'

    This view incorporates many images taken by Opportunity's panoramic camera (Pancam) from the 1,332nd through 1,379th Martian days, or sols, of the mission (Oct. 23 to Dec. 11, 2007). It combines a stereo pair so that it appears three-dimensional when seen through blue-red glasses. Some visible patterns in dark and light tones are the result of combining frames that were affected by dust on the front sapphire window of the rover's camera.

    Opportunity landed on Jan. 25, 2004, Universal Time, (Jan. 24, Pacific Time) inside a much smaller crater about 6 kilometers (4 miles) north of Victoria Crater, to begin a surface mission designed to last 3 months and drive about 600 meters (0.4 mile).

  16. On the Rim of 'Victoria Crater' (Stereo)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Left-eye view of a stereo pair for PIA08780

    [figure removed for brevity, see original site] Right-eye view of a stereo pair for PIA08780

    NASA's Mars rover Opportunity reached the rim of 'Victoria Crater' in Mars' Meridiani Planum region with a 26-meter (85-foot) drive during the rover's 951st Martian day, or sol (Sept. 26, 2006). After the drive, the rover's navigation camera took the three exposures combined into this view of the crater's interior. This crater has been the mission's long-term destination for the past 21 Earth months.

    A half mile in the distance one can see about 20 percent of the far side of the crater framed by the rocky cliffs in the foreground to the left and right of the image. The rim of the crater is composed of alternating promontories, rocky points towering approximately 70 meters (230 feet) above the crater floor, and recessed alcoves. The bottom of the crater is covered by sand that has been shaped into ripples by the Martian wind.

    The position at the end of the sol 951 drive is about six meters from the lip of an alcove called 'Duck Bay.' The rover team planned a drive for sol 952 that would move a few more meters forward, plus more imaging of the near and far walls of the crater.

    Victoria Crater is about five times wider than 'Endurance Crater,' which Opportunity spent six months examining in 2004, and about 40 times wider than 'Eagle Crater,' where Opportunity first landed.

    This view is presented as a cylindrical-perspective projection with geometric seam correction.

  17. [Olindias sambaquiensis jellyfish sting. Analysis of 49 cases].

    PubMed

    Mosovich, Juan H; Young, Pablo

    2012-01-01

    Olindias sambaquiensis jellyfish sting occurs frequently in Buenos Aires province coast beaches. Among five hundred and one thousand stings by jellyfish are reported each season at Monte Hermoso, a beach village in the South of Buenos Aires province. The skin damage provoked because of its highly irritant effect poses a serious issue related to tourism development. A total number of 49 cases that were examined during the first hour after the sting were enrolled in Monte Hermoso during January 1998. Twenty eight were males (57.1%). The average age was 16 ± 4.1 (range 5-80). Of them, 54% showed linear erythema-edematous lesions, 28% showed predominantly erythematous lesions, and in 18% the injuries were erythema-edematous plaques. In 73% of the cases the lesions were located in lower limbs. We had hereby redefined cutaneous lesions produced by O. sambaquiensis, its evolution, its dimensions and most frequent localizations. Besides, it has been typified and quantified the pain it provokes and other signs and symptoms that go with the sting during the posterior hour, during the first 24 hours, and after 30 days. We described the therapeutic conducts used in our coasts and we assessed the effectiveness of some of them in pain control, and finally we propose a therapeutic scheme for this sting.

  18. A tissue-engineered jellyfish with biomimetic propulsion

    PubMed Central

    Nawroth, Janna C; Lee, Hyungsuk; Feinberg, Adam W; Ripplinger, Crystal M; McCain, Megan L; Grosberg, Anna; Dabiri, John O; Parker, Kevin Kit

    2014-01-01

    Reverse engineering of biological form and function requires hierarchical design over several orders of space and time. Recent advances in the mechanistic understanding of biosynthetic compound materials1–3, computer-aided design approaches in molecular synthetic biology4,5 and traditional soft robotics6,7, and increasing aptitude in generating structural and chemical microenvironments that promote cellular self-organization8–10 have enhanced the ability to recapitulate such hierarchical architecture in engineered biological systems. Here we combined these capabilities in a systematic design strategy to reverse engineer a muscular pump. We report the construction of a freely swimming jellyfish from chemically dissociated rat tissue and silicone polymer as a proof of concept. The constructs, termed ‘medusoids’, were designed with computer simulations and experiments to match key determinants of jellyfish propulsion and feeding performance by quantitatively mimicking structural design, stroke kinematics and animal-fluid interactions. The combination of the engineering design algorithm with quantitative benchmarks of physiological performance suggests that our strategy is broadly applicable to reverse engineering of muscular organs or simple life forms that pump to survive. PMID:22820316

  19. Box jellyfish envenomation: case report of effective lemon and oil emulsion treatment.

    PubMed

    Hamann, Carsten R; Hamann, Dathan; Richardson, Clare; Seeburger, Jack

    2014-04-01

    Box jellyfish are highly venomous and numerous possible treatments for envenomation have already been reported in the published literature. The hand of a 55-year-old scuba diver was stung in the Gulf of Guinea resulting in two crops of coalescing vesicles with intense pain and lymphadenopathy. Traditional therapies such as hot water, cold packs and acetic acid were ineffective. Symptoms were rapidly relieved after the application of a lemon-oil emulsion balm. Treatments for jellyfish envenomation generally aim to either denature the jellyfish venom or prevent the discharge of the venom. Lemon-oil emulsion therapy has not yet been reported in the published literature but may be an economical and novel treatment for box jellyfish envenomation.

  20. Ecological Biogeography of the Terrestrial Nematodes of Victoria Land, Antarctica

    PubMed Central

    Adams, Byron J.; Wall, Diana H.; Virginia, Ross A.; Broos, Emma; Knox, Matthew A.

    2014-01-01

    Abstract The terrestrial ecosystems of Victoria Land, Antarctica are characteristically simple in terms of biological diversity and ecological functioning. Nematodes are the most commonly encountered and abundant metazoans of Victoria Land soils, yet little is known of their diversity and distribution. Herein we present a summary of the geographic distribution, habitats and ecology of the terrestrial nematodes of Victoria Land from published and unpublished sources. All Victoria Land nematodes are endemic to Antarctica, and many are common and widely distributed at landscape scales. However, at smaller spatial scales, populations can have patchy distributions, with the presence or absence of each species strongly influenced by specific habitat requirements. As the frequency of nematode introductions to Antarctica increases, and soil habitats are altered in response to climate change, our current understanding of the environmental parameters associated with the biogeography of Antarctic nematofauna will be crucial to monitoring and possibly mitigating changes to these unique soil ecosystems. PMID:25061360

  1. Imaging individual green fluorescent proteins

    NASA Astrophysics Data System (ADS)

    Pierce, Daniel W.; Hom-Booher, Nora; Vale, Ronald D.

    1997-07-01

    Recent advances in fluorescence microscopy techniques have allowed the video-time imaging of single molecules of fluorescent dyes covalently bound to proteins in aqueous environments. However, the techniques have not been exploited fully because proteins can be difficult to label, and dye modification may cause partial or complete loss of activity. These difficulties could be circumvented by fusing proteins to green fluorescent protein (GFP) of the jellyfish Aequorea victoria. Here we report that single S65T mutant GFP molecules can be imaged using total internal reflection microscopy, and that ATP-driven movement of an individual kinesin molecule (a microtubule motor protein) fused to GFP can be readily observed.

  2. Using targeted variants of aequorin to measure Ca2+ levels in intracellular organelles.

    PubMed

    Granatiero, Veronica; Patron, Maria; Tosatto, Anna; Merli, Giulia; Rizzuto, Rosario

    2014-01-01

    Aequorin is a Ca(2+)-sensitive photoprotein isolated from the jellyfish Aequorea victoria. It is an ideal probe for measuring Ca(2+) concentration ([Ca(2+)]) in intracellular organelles because it can be modified to include specific targeting sequences. On the binding of Ca(2+) to three high-affinity sites in aequorin, an irreversible reaction occurs in which the prosthetic group coelenterazine is released and a photon is emitted. This protocol presents procedures for expressing, targeting, and reconstituting aequorin in intact and permeabilized mammalian cells and describes how to use this photoprotein to measure intracellular [Ca(2+)] in various subcellular compartments.

  3. Dangers in the ocean: the traveler and marine envenomation. I. jellyfish.

    PubMed

    Fenner, P J

    1998-09-01

    Envenomation by marine creatures is more common than is often realized, and regularly accounts for both death and severe morbidity in humans. Worldwide marine envenomation morbidity and mortality result from two main animal groups: (1) jellyfish, and (2) "other" marine animals. Venomous jellyfish are discussed in part I of this article, with relevant information on their distribution and appearance, and on symptoms of envenomation; first aid and medical treatment are also suggested.

  4. Successful use of heat as first aid for tropical Australian jellyfish stings.

    PubMed

    Little, Mark; Fitzpatrick, Richard; Seymour, Jamie

    2016-11-01

    Currently the Australian Resuscitation Council (ARC) recommends dousing with vinegar followed by ice as first aid for jellyfish stings in tropical Australia, with limited evidence to support this recommendation (Li et al., 2013). We report our successful experience in using hot water immersion as first aid in treating two people stung by venomous tropical Australian jellyfish, one by Chironex fleckeri and one by Carukia barnesi.

  5. Jellyfish blooms result in a major microbial respiratory sink of carbon in marine systems.

    PubMed

    Condon, Robert H; Steinberg, Deborah K; del Giorgio, Paul A; Bouvier, Thierry C; Bronk, Deborah A; Graham, William M; Ducklow, Hugh W

    2011-06-21

    Jellyfish blooms occur in many estuarine and coastal regions and may be increasing in their magnitude and extent worldwide. Voracious jellyfish predation impacts food webs by converting large quantities of carbon (C), fixed by primary producers and consumed by secondary producers, into gelatinous biomass, which restricts C transfer to higher trophic levels because jellyfish are not readily consumed by other predators. In addition, jellyfish release colloidal and dissolved organic matter (jelly-DOM), and could further influence the functioning of coastal systems by altering microbial nutrient and DOM pathways, yet the links between jellyfish and bacterioplankton metabolism and community structure are unknown. Here we report that jellyfish released substantial quantities of extremely labile C-rich DOM, relative to nitrogen (25.6 ± 31.6 C:1N), which was quickly metabolized by bacterioplankton at uptake rates two to six times that of bulk DOM pools. When jelly-DOM was consumed it was shunted toward bacterial respiration rather than production, significantly reducing bacterial growth efficiencies by 10% to 15%. Jelly-DOM also favored the rapid growth and dominance of specific bacterial phylogenetic groups (primarily γ-proteobacteria) that were rare in ambient waters, implying that jelly-DOM was channeled through a small component of the in situ microbial assemblage and thus induced large changes in community composition. Our findings suggest major shifts in microbial structure and function associated with jellyfish blooms, and a large detour of C toward bacterial CO(2) production and away from higher trophic levels. These results further suggest fundamental transformations in the biogeochemical functioning and biological structure of food webs associated with jellyfish blooms.

  6. Victoria Land, Ross Sea, and Ross Ice Shelf, Antarctica

    NASA Technical Reports Server (NTRS)

    2002-01-01

    On December 19, 2001, MODIS acquired data that produced this image of Antarctica's Victoria Land, Ross Ice Shelf, and the Ross Sea. The coastline that runs up and down along the left side of the image denotes where Victoria Land (left) meets the Ross Ice Shelf (right). The Ross Ice Shelf is the world's largest floating body of ice, approximately the same size as France. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  7. A review of the Victoria, Australia granny flat program.

    PubMed

    Lazarowich, N M

    1990-04-01

    The 10-year-old Victoria, Australia granny flat program has about 3000 units in place. Granny flats, designed as standardized units using panels, offer privacy yet proximity to family members. There are suggestions they be considered as affordable housing for younger people. This review of the Victoria program suggests that state initiatives are more successful than local ones, and that decentralized administration is associated with increased ability to delivery the granny flat units.

  8. Jellyfish-associated bacterial communities and bacterioplankton in Indonesian Marine lakes.

    PubMed

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

    2016-05-01

    In the present study, we compared communities of bacteria in two jellyfish species (the 'golden' jellyfish Mastigias cf.papua and the box jellyfish Tripedalia cf.cystophora) and water in three marine lakes located in the Berau region of northeastern Borneo, Indonesia. Jellyfish-associated bacterial communities were compositionally distinct and less diverse than bacterioplankton communities. Alphaproteobacteria, Gammaproteobacteria, Synechococcophycidae and Flavobacteriia were the most abundant classes in water. Jellyfish-associated bacterial communities were dominated by OTUs assigned to the Gammaproteobacteria (family Endozoicimonaceae), Mollicutes, Spirochaetes and Alphaproteobacteria (orders Kiloniellales and Rhodobacterales). Mollicutes were mainly restricted to Mastigias whereas Spirochaetes and the order Kiloniellales were most abundant in Tripedalia hosts. The most abundant OTU overall in jellyfish hosts was assigned to the family Endozoicimonaceae and was highly similar to organisms in Genbank obtained from various hosts including an octocoral, bivalve and fish species. Other abundant OTUs included an OTU assigned to the order Entomoplasmatales and mainly found in Mastigias hosts and OTUs assigned to the Spirochaetes and order Kiloniellales and mainly found in Tripedalia hosts. The low sequence similarity of the Entomoplasmatales OTU to sequences in Genbank suggests that it may be a novel lineage inhabiting Mastigias and possibly restricted to marine lakes.

  9. Characterization and neutralization of Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom using polyclonal antibody.

    PubMed

    Kang, Changkeun; Han, Dae-Yong; Park, Kwang-Il; Pyo, Min-Jung; Heo, Yunwi; Lee, Hyunkyoung; Kim, Gon Sup; Kim, Euikyung

    2014-08-01

    Jellyfish stings have often caused serious health concerns for sea bathers especially in tropical waters. In the coastal areas of Korea, China and Japan, the blooming and stinging accidents of poisonous jellyfish species have recently increased, including Nemopilema nomurai. We have generated a polyclonal antibody against N. nomurai jellyfish venom (NnV) by the immunization of white rabbits with NnV antigen. In the present study, the antibody has been characterized for its neutralizing effect against NnV. At first, the presence of NnV polyclonal antibody has been confirmed from the immunized rabbit serum by Enzyme linked immunosorbent assay (ELISA). Then, the neutralizing activities of the polyclonal antibody have been investigated using cell-based toxicity test, hemolysis assay, and mice lethality test. When the polyclonal antibody was preincubated with NnV, it shows a high effectiveness in neutralizing the NnV toxicities in a concentration-dependent manner. Moreover, we explored proteomic analyses using 2-D SDS-PAGE and MALDI-TOF mass spectrometry to illustrate the molecular identities of the jellyfish venom. From this, 18 different protein families have been identified as jellyfish venom-derived proteins; the main findings of which are matrix metalloproteinase-14, astacin-like metalloprotease toxin 3 precursor. It is expected that the present results would have contributed to our understandings of the envenomation by N. nomurai, their treatment and some valuable knowledge on the pathological processes of the jellyfish stinging.

  10. Extract from the zooxanthellate jellyfish Cotylorhiza tuberculata modulates gap junction intercellular communication in human cell cultures.

    PubMed

    Leone, Antonella; Lecci, Raffaella Marina; Durante, Miriana; Piraino, Stefano

    2013-05-22

    On a global scale, jellyfish populations in coastal marine ecosystems exhibit increasing trends of abundance. High-density outbreaks may directly or indirectly affect human economical and recreational activities, as well as public health. As the interest in biology of marine jellyfish grows, a number of jellyfish metabolites with healthy potential, such as anticancer or antioxidant activities, is increasingly reported. In this study, the Mediterranean "fried egg jellyfish" Cotylorhiza tuberculata (Macri, 1778) has been targeted in the search forputative valuable bioactive compounds. A medusa extract was obtained, fractionated, characterized by HPLC, GC-MS and SDS-PAGE and assayed for its biological activity on breast cancer cells (MCF-7) and human epidermal keratinocytes (HEKa). The composition of the jellyfish extract included photosynthetic pigments, valuable ω-3 and ω-6 fatty acids, and polypeptides derived either from jellyfish tissues and their algal symbionts. Extract fractions showed antioxidant activity and the ability to affect cell viability and intercellular communication mediated by gap junctions (GJIC) differentially in MCF-7 and HEKa cells. A significantly higher cytotoxicity and GJIC enhancement in MCF-7 compared to HEKa cells was recorded. A putative action mechanism for the anticancer bioactivity through the modulation of GJIC has been hypothesized and its nutraceutical and pharmaceutical potential was discussed.

  11. Comprehensive analysis of the origin of giant jellyfish near Qinhuangdao in summer

    NASA Astrophysics Data System (ADS)

    Wu, Lingjuan; Wu, Xiaofen; Bai, Tao

    2016-09-01

    A massive bloom of the giant jellyfish Nemopilema nomurai occurred in waters off Qinhuangdao, a port city in Hebei Province, in July 2013. However, jellyfish larvae were not found in this location during the previous winter and spring. To determine the possible origin of the giant jellyfish medusa in the Bohai Sea, we developed a backward particle-tracking model and a series of numerical simulations were conducted by using the hydrodynamic, three-dimensional Regional Ocean Modeling System (ROMS) results. The simulated results showed that passive particles, representing jellyfish medusae, released in surface waters at diff erent dates during the summer had consistent trajectories. Particles released at the sea surface on August 1 and 15 could be traced back to the center of the Bohai Sea and to waters between Feiyan Shoal and the new Huanghe (Yellow) River estuary. Particles released on July 1 and 15 could also be traced back to the center of the Bohai Sea and to waters between Feiyan Shoal and only to Zhuangxi tide station. However, none of the particles released in the middle and bottom water layers could be traced back to those areas. Based on the results of the numerical simulations, the distribution characteristics of seafloor sediments, and observational data for giant jellyfish in the region, we suggest that waters between Feiyan Shoal and the new Huanghe River estuary are the likely origin of giant jellyfish observed near Qinhuangdao in summer.

  12. High activity and Levy searches: jellyfish can search the water column like fish.

    PubMed

    Hays, Graeme C; Bastian, Thomas; Doyle, Thomas K; Fossette, Sabrina; Gleiss, Adrian C; Gravenor, Michael B; Hobson, Victoria J; Humphries, Nicolas E; Lilley, Martin K S; Pade, Nicolas G; Sims, David W

    2012-02-07

    Over-fishing may lead to a decrease in fish abundance and a proliferation of jellyfish. Active movements and prey search might be thought to provide a competitive advantage for fish, but here we use data-loggers to show that the frequently occurring coastal jellyfish (Rhizostoma octopus) does not simply passively drift to encounter prey. Jellyfish (327 days of data from 25 jellyfish with depth collected every 1 min) showed very dynamic vertical movements, with their integrated vertical movement averaging 619.2 m d(-1), more than 60 times the water depth where they were tagged. The majority of movement patterns were best approximated by exponential models describing normal random walks. However, jellyfish also showed switching behaviour from exponential patterns to patterns best fitted by a truncated Lévy distribution with exponents (mean μ=1.96, range 1.2-2.9) close to the theoretical optimum for searching for sparse prey (μopt≈2.0). Complex movements in these 'simple' animals may help jellyfish to compete effectively with fish for plankton prey, which may enhance their ability to increase in dominance in perturbed ocean systems.

  13. Decomposition of jellyfish carrion in situ: Short-term impacts on infauna, benthic nutrient fluxes and sediment redox conditions.

    PubMed

    Chelsky, Ariella; Pitt, Kylie A; Ferguson, Angus J P; Bennett, William W; Teasdale, Peter R; Welsh, David T

    2016-10-01

    Jellyfish often form blooms that persist for weeks to months before they collapse en masse, resulting in the sudden release of large amounts of organic matter to the environment. This study investigated the biogeochemical and ecological effects of the decomposition of jellyfish in a shallow coastal lagoon in New South Wales, Australia. Catostylus mosaicus carrion was added to the surface of shallow sub-tidal sediments and biogeochemical parameters and macrofaunal abundance immediately below the jellyfish carrion were measured over three days. Sediment plots without jellyfish served as controls. Sediment oxygen demand and carbon and nitrogen efflux increased by up to 60-fold in the jellyfish plots, compared to control plots, and dissolved organic nutrient fluxes were more sustained than in previous studies due to the use of fresh rather than frozen biomass. The decomposing jellyfish progressively altered sediment redox conditions, indicated by an increase in porewater iron (II) and sulfide concentrations measured by high-resolution in situ diffusive samplers. Abundance of some macrofaunal taxa in the jellyfish plots decreased relative to controls, however, the abundance of a carnivorous gastropod, which was presumably feeding on the carrion, increased in the jellyfish plots. While jellyfish carrion may be a food source for some macrofauna, low oxygen conditions coupled with the accumulation of toxic dissolved sulfides in the near-surface sediments may explain the overall change in the macroinfaunal community.

  14. 'Lyell' Panorama inside Victoria Crater (False Color)

    NASA Technical Reports Server (NTRS)

    2008-01-01

    During four months prior to the fourth anniversary of its landing on Mars, NASA's Mars Exploration Rover Opportunity examined rocks inside an alcove called 'Duck Bay' in the western portion of Victoria Crater. The main body of the crater appears in the upper right of this stereo panorama, with the far side of the crater lying about 800 meters (half a mile) away. Bracketing that part of the view are two promontories on the crater's rim at either side of Duck Bay. They are 'Cape Verde,' about 6 meters (20 feet) tall, on the left, and 'Cabo Frio,' about 15 meters (50 feet) tall, on the right. The rest of the image, other than sky and portions of the rover, is ground within Duck Bay.

    Opportunity's targets of study during the last quarter of 2007 were rock layers within a band exposed around the interior of the crater, about 6 meters (20 feet) from the rim. Bright rocks within the band are visible in the foreground of the panorama. The rover science team assigned informal names to three subdivisions of the band: 'Steno,' 'Smith,' and 'Lyell.'

    This view combines many images taken by Opportunity's panoramic camera (Pancam) from the 1,332nd through 1,379th Martian days, or sols, of the mission (Oct. 23 to Dec. 11, 2007). Images taken through Pancam filters centered on wavelengths of 753 nanometers, 535 nanometers and 432 nanometers were mixed to produce this view, which is presented in a false-color stretch to bring out subtle color differences in the scene. Some visible patterns in dark and light tones are the result of combining frames that were affected by dust on the front sapphire window of the rover's camera.

  15. Opportunity's First Dip into Victoria Crater

    NASA Technical Reports Server (NTRS)

    2007-01-01

    NASA's Mars Exploration Rover Opportunity entered Victoria Crater during the rover's 1,291st Martian day, or sol, (Sept. 11, 2007). The rover team commanded Opportunity to drive just far enough into the crater to get all six wheels onto the inner slope, and then to back out again and assess how much the wheels slipped on the slope. The driving commands for the day included a precaution for the rover to stop driving if the wheels were slipping more than 40 percent. Slippage exceeded that amount on the last step of the drive, so Opportunity stopped with its front pair of wheels still inside the crater. The rover team planned to assess results of the drive, then start Opportunity on an extended exploration inside the crater.

    This wide-angle view taken by Opportunity's front hazard-identification camera at the end of the day's driving shows the wheel tracks created by the short dip into the crater. The left half of the image looks across an alcove informally named 'Duck Bay' toward a promontory called 'Cape Verde' clockwise around the crater wall. The right half of the image looks across the main body of the crater, which is 800 meters (half a mile) in diameter.

  16. Complete mitochondrial genome of the jellyfish, Chrysaora quinquecirrha (Cnidaria, Scyphozoa).

    PubMed

    Hwang, Dae-Sik; Park, Eunji; Won, Yong-Jin; Lee, Woo-Jin; Shin, Kyoungsoon; Lee, Jae-Seong

    2014-02-01

    We sequenced 16,775 bp of the linear mitochondrial DNA of the jellyfish Chrysaora quinquecirrha and characterized them. C. quinquecirrha has 13 protein-coding genes (PCGs), 16S rRNA and 12S rRNA with 3 tRNAs (tRNA-Leu, tRNA-Ser(TGA), tRNA-Met) as shown in Aurelia sp. nov. Both have another two PCGs such as helicase and orf363 with telomeres at both ends. The PCGs of C. quinquecirrha shows anti-G bias on 2nd and 3rd positions of PCGs as well as anti-C bias on 1st and 3rd positions of PCGs.

  17. Hovering of a jellyfish-like flying machine

    NASA Astrophysics Data System (ADS)

    Ristroph, Leif; Childress, Stephen

    2013-11-01

    Ornithopters, or flapping-wing aircraft, offer an alternative to helicopters in achieving maneuverability at small scales, although stabilizing such aerial vehicles remains a key challenge. Here, we present a hovering machine that achieves self-righting flight using flapping wings alone, without relying on additional aerodynamic surfaces and without feedback control. We design, construct, and test-fly a prototype that opens and closes four wings, resembling the motions of swimming jellyfish more so than any insect or bird. Lift measurements and high-speed video of free-flight are used to inform an aerodynamic model that explains the stabilization mechanism. These results show the promise of flapping-flight strategies beyond those that directly mimic the wing motions of flying animals.

  18. GFP-like proteins stably accumulate in lysosomes.

    PubMed

    Katayama, Hiroyuki; Yamamoto, Akitsugu; Mizushima, Noboru; Yoshimori, Tamotsu; Miyawaki, Atsushi

    2008-01-01

    Green fluorescent protein (GFP) from the jellyfish Aequorea victoria, its GFP variants (Aequorea GFPs), and more recently the novel GFP-like proteins from Anthozoa have greatly advanced our technologies for fluorescently labeling cells, organelles, and proteins. It has been shown, however, that some GFP-like proteins have a tendency to oligomerize and aggregate. Transfection of GFP-like proteins into cultured mammalian cells results in bright punctate structures, which are thought to be cytosolic protein aggregates. In this study, we demonstrate that these structures are not cytosolic aggregates but lysosomes that have accumulated the GFP-like proteins. Our biochemical and immunocytochemical experiments have revealed that certain GFP-like proteins expressed in the cytosol enter lysosomes possibly by an autophagy-related mechanism, but retain their fluorescence because of resistance not only to acidity but also to lysosomal proteases.

  19. Hydrogen-fuel-powered bell segments of biomimetic jellyfish

    NASA Astrophysics Data System (ADS)

    Tadesse, Yonas; Villanueva, Alex; Haines, Carter; Novitski, David; Baughman, Ray; Priya, Shashank

    2012-04-01

    Artificial muscles powered by a renewable energy source are desired for joint articulation in bio-inspired autonomous systems. In this study, a robotic underwater vehicle, inspired by jellyfish, was designed to be actuated by a chemical fuel source. The fuel-powered muscles presented in this work comprise nano-platinum catalyst-coated multi-wall carbon nanotube (MWCNT) sheets, wrapped on the surface of nickel-titanium (NiTi) shape memory alloy (SMA). As a mixture of oxygen and hydrogen gases makes contact with the platinum, the resulting exothermic reaction activates the nickel-titanium (NiTi)-based SMA. The MWCNT sheets serve as a support for the platinum particles and enhance the heat transfer due to the high thermal conductivity between the composite and the SMA. A hydrogen and oxygen fuel source could potentially provide higher power density than electrical sources. Several vehicle designs were considered and a peripheral SMA configuration under the robotic bell was chosen as the best arrangement. Constitutive equations combined with thermodynamic modeling were developed to understand the influence of system parameters that affect the overall actuation behavior of the fuel-powered SMA. The model is based on the changes in entropy of the hydrogen and oxygen fuel on the composite actuator within a channel. The specific heat capacity is the dominant factor controlling the width of the strain for various pulse widths of fuel delivery. Both theoretical and experimental strains for different diameter (100 and 150 µm) SMA/MWCNT/Pt fuel-powered muscles with dead weight attached at the end exhibited the highest magnitude under 450 ms of fuel delivery within 1.6 mm diameter conduit size. Fuel-powered bell deformation of 13.5% was found to be comparable to that of electrically powered (29%) and natural jellyfish (42%).

  20. Lipid Profile in Different Parts of Edible Jellyfish Rhopilema esculentum.

    PubMed

    Zhu, Si; Ye, Mengwei; Xu, Jilin; Guo, Chunyang; Zheng, Huakun; Hu, Jiabao; Chen, Juanjuan; Wang, Yajun; Xu, Shanliang; Yan, Xiaojun

    2015-09-23

    Jellyfish Rhopilema esculentum has been exploited commercially as a delicious food for a long time. Although the edible and medicinal values of R. esculentum have gained extensive attention, the effects of lipids on its nutritional value have rarely been reported. In the present of study, the lipid profile including lipid classes, fatty acyl compositions, and fatty acid (FA) positions in lipids from different parts (oral arms, umbrella, and mouth stalk) of R. esculentum was explored by ultraperformance liquid chromatography--electrospray ionization--quadrupole time-of-flight mass spectrometry (UPLC-ESI-Q-TOF-MS). More than 87 species from 10 major lipid classes including phosphatidylcholine (PC), lysophosphatidylcholine (LPC), phosphatidylethanolamine (PE), lysophosphatidylethanolamine (LPE), phosphatidylinositol (PI), lysophosphatidylinositol (LPI), phosphatidylserine (PS), ceramide (Cer), ceramide 2-aminoethylphosphonate (CAEP), and triacylglycerol (TAG) were separated and characterized. Semiquantification of individual lipid species in different parts of R. esculentum was also conducted. Results showed that glycerophospholipids (GPLs) enriched in highly unsaturated fatty acids (HUFAs) were the major compenents in all parts of R. esculentum, which accounted for 54-63% of total lipids (TLs). Considering the high level of GPLs and the FA compositions in GPLs, jellyfish R. esculentum might have great potential as a health-promoting food for humans and as a growth-promoting diet for some commercial fish and crustaceans. Meanwhile, LPC, LPE, and LPI showed high levels in oral arms when compared with umbrella and mouth stalk, which may be due to the high proportion of phospholipase A2 (PLA2) in oral arms. Moreover, a high CAEP level was detected in oral arms, which may render cell membranes with resistance to chemical hydrolysis by PLA2. The relatively low TAG content could be associated with specific functions of oral arms.

  1. Current-oriented swimming by jellyfish and its role in bloom maintenance.

    PubMed

    Fossette, Sabrina; Gleiss, Adrian Christopher; Chalumeau, Julien; Bastian, Thomas; Armstrong, Claire Denise; Vandenabeele, Sylvie; Karpytchev, Mikhail; Hays, Graeme Clive

    2015-02-02

    Cross-flows (winds or currents) affect animal movements [1-3]. Animals can temporarily be carried off course or permanently carried away from their preferred habitat by drift depending on their own traveling speed in relation to that of the flow [1]. Animals able to only weakly fly or swim will be the most impacted (e.g., [4]). To circumvent this problem, animals must be able to detect the effects of flow on their movements and respond to it [1, 2]. Here, we show that a weakly swimming organism, the jellyfish Rhizostoma octopus, can orientate its movements with respect to currents and that this behavior is key to the maintenance of blooms and essential to reduce the probability of stranding. We combined in situ observations with first-time deployment of accelerometers on free-ranging jellyfish and simulated the behavior observed in wild jellyfish within a high-resolution hydrodynamic model. Our results show that jellyfish can actively swim countercurrent in response to current drift, leading to significant life-history benefits, i.e., increased chance of survival and facilitated bloom formation. Current-oriented swimming may be achieved by jellyfish either directly detecting current shear across their body surface [5] or indirectly assessing drift direction using other cues (e.g., magnetic, infrasound). Our coupled behavioral-hydrodynamic model provides new evidence that current-oriented swimming contributes to jellyfish being able to form aggregations of hundreds to millions of individuals for up to several months, which may have substantial ecosystem and socioeconomic consequences [6, 7]. It also contributes to improve predictions of jellyfish blooms' magnitude and movements in coastal waters.

  2. Isolation, characterization and biological evaluation of jellyfish collagen for use in biomedical applications.

    PubMed

    Addad, Sourour; Exposito, Jean-Yves; Faye, Clément; Ricard-Blum, Sylvie; Lethias, Claire

    2011-01-01

    Fibrillar collagens are the more abundant extracellular proteins. They form a metazoan-specific family, and are highly conserved from sponge to human. Their structural and physiological properties have been successfully used in the food, cosmetic, and pharmaceutical industries. On the other hand, the increase of jellyfish has led us to consider this marine animal as a natural product for food and medicine. Here, we have tested different Mediterranean jellyfish species in order to investigate the economic potential of their collagens. We have studied different methods of collagen purification (tissues and experimental procedures). The best collagen yield was obtained using Rhizostoma pulmo oral arms and the pepsin extraction method (2-10 mg collagen/g of wet tissue). Although a significant yield was obtained with Cotylorhiza tuberculata (0.45 mg/g), R. pulmo was used for further experiments, this jellyfish being considered as harmless to humans and being an abundant source of material. Then, we compared the biological properties of R. pulmo collagen with mammalian fibrillar collagens in cell cytotoxicity assays and cell adhesion. There was no statistical difference in cytotoxicity (p > 0.05) between R. pulmo collagen and rat type I collagen. However, since heparin inhibits cell adhesion to jellyfish-native collagen by 55%, the main difference is that heparan sulfate proteoglycans could be preferentially involved in fibroblast and osteoblast adhesion to jellyfish collagens. Our data confirm the broad harmlessness of jellyfish collagens, and their biological effect on human cells that are similar to that of mammalian type I collagen. Given the bioavailability of jellyfish collagen and its biological properties, this marine material is thus a good candidate for replacing bovine or human collagens in selected biomedical applications.

  3. [Release and supplement of carbon, nitrogen and phosphorus from jellyfish (Nemopilema nomurai) decomposition in seawater].

    PubMed

    Qu, Chang-feng; Song, Jin-ming; Li, Ning; Li, Xue-gang; Yuan, Hua-mao; Duan, Li-qin

    2016-01-01

    Abstract: Jellyfish bloom has been increasing in Chinese seas and decomposition after jellyfish bloom has great influences on marine ecological environment. We conducted the incubation of Nemopilema nomurai decomposing to evaluate its effect on carbon, nitrogen and phosphorus recycling of water column by simulated experiments. The results showed that the processes of jellyfish decomposing represented a fast release of biogenic elements, and the release of carbon, nitrogen and phosphorus reached the maximum at the beginning of jellyfish decomposing. The release of biogenic elements from jellyfish decomposition was dominated by dissolved matter, which had a much higher level than particulate matter. The highest net release rates of dissolved organic carbon and particulate organic carbon reached (103.77 ± 12.60) and (1.52 ± 0.37) mg · kg⁻¹ · h⁻¹, respectively. The dissolved nitrogen was dominated by NH₄⁺-N during the whole incubation time, accounting for 69.6%-91.6% of total dissolved nitrogen, whereas the dissolved phosphorus was dominated by dissolved organic phosphorus during the initial stage of decomposition, being 63.9%-86.7% of total dissolved phosphorus and dominated by PO₄³⁻-P during the late stage of decomposition, being 50.4%-60.2%. On the contrary, the particulate nitrogen was mainly in particulate organic nitrogen, accounting for (88.6 ± 6.9) % of total particulate nitrogen, whereas the particulate phosphorus was mainly in particulate. inorganic phosphorus, accounting for (73.9 ±10.5) % of total particulate phosphorus. In addition, jellyfish decomposition decreased the C/N and increased the N/P of water column. These indicated that jellyfish decomposition could result in relative high carbon and nitrogen loads.

  4. Target organ identification of jellyfish envenomation using systemic and integrative analyses in anesthetized dogs.

    PubMed

    Kang, Changkeun; Kim, Young Ki; Lee, Hyunkyoung; Cha, Mijin; Sohn, Eun-Tae; Jung, Eun-Sun; Song, Chiyoun; Kim, Minkyung; Lee, Hee Chun; Kim, Jong-Shu; Hwang, Jin-Yong; Yoon, Won Duk; Kim, Euikyung

    2011-01-01

    Proper treatment of jellyfish envenomed patients can be successfully achieved only from an understanding of the overall functional changes and alterations in physiological parameters under its envenomation. The majority of previous investigations on jellyfish venoms have covered only a couple of parameters at a time. Unlike most other fragmentary jellyfish studies, we employed an integrative toxicological approach, including hemodynamics, clinical chemistry and hematology analyses, using N. nomurai jellyfish venom (NnV) in dogs. After the baseline measurements for mean arterial pressure (MAP), cardiac output (CO) and heart rate (HR), NnV was intravenously administered to the dogs at doses of 0.1 or 0.3mg/kg body weight. The dogs showed significant decreases in MAP (-27.4±3.7 and -48.1±9.9 mmHg), CO (-1.1±0.1 L/min and -1.0±0.2 L/min), and HR (-4.5±0.3 and -9.9±3.1 beats/min) comparing with the respective baseline controls. The onset of systemic hypotension and bradycardia occurred within 1 min of NnV injection and they lasted for 1-35 min, depending on the NnV doses. Interestingly, serum biochemical analyses of envenomed dogs exhibited dramatic increases of alkaline phosphatase (ALP), creatine phosphokinase (CPK), alanine aminotransferase (ALT) and aspartate aminotransferase (AST), indicating its possible target organs. In conclusion, we have demonstrated simultaneously, for the first time, the multiple organ toxicities (cardiotoxic, myotoxic and hepatotoxic) of a scyphozoan jellyfish venom. Based on these results, an integrative toxinological approach using dogs appears to be effective in predicting jellyfish venom toxicities and designing their therapeutic strategies. We expect this method can be applied to other jellyfish venom research as well.

  5. Jellyfish Stings Trigger Gill Disorders and Increased Mortality in Farmed Sparus aurata (Linnaeus, 1758) in the Mediterranean Sea.

    PubMed

    Bosch-Belmar, Mar; M'Rabet, Charaf; Dhaouadi, Raouf; Chalghaf, Mohamed; Daly Yahia, Mohamed Néjib; Fuentes, Verónica; Piraino, Stefano; Kéfi-Daly Yahia, Ons

    2016-01-01

    Jellyfish are of particular concern for marine finfish aquaculture. In recent years repeated mass mortality episodes of farmed fish were caused by blooms of gelatinous cnidarian stingers, as a consequence of a wide range of hemolytic, cytotoxic, and neurotoxic properties of associated cnidocytes venoms. The mauve stinger jellyfish Pelagia noctiluca (Scyphozoa) has been identified as direct causative agent for several documented fish mortality events both in Northern Europe and the Mediterranean Sea aquaculture farms. We investigated the effects of P. noctiluca envenomations on the gilthead sea bream Sparus aurata by in vivo laboratory assays. Fish were incubated for 8 hours with jellyfish at 3 different densities in 300 l experimental tanks. Gill disorders were assessed by histological analyses and histopathological scoring of samples collected at time intervals from 3 hours to 4 weeks after initial exposure. Fish gills showed different extent and severity of gill lesions according to jellyfish density and incubation time, and long after the removal of jellyfish from tanks. Jellyfish envenomation elicits local and systemic inflammation reactions, histopathology and gill cell toxicity, with severe impacts on fish health. Altogether, these results shows P. noctiluca swarms may represent a high risk for Mediterranean finfish aquaculture farms, generating significant gill damage after only a few hours of contact with farmed S. aurata. Due to the growth of the aquaculture sector and the increased frequency of jellyfish blooms in the coastal waters, negative interactions between stinging jellyfish and farmed fish are likely to increase with the potential for significant economic losses.

  6. Jellyfish Stings Trigger Gill Disorders and Increased Mortality in Farmed Sparus aurata (Linnaeus, 1758) in the Mediterranean Sea

    PubMed Central

    Dhaouadi, Raouf; Chalghaf, Mohamed; Daly Yahia, Mohamed Néjib; Fuentes, Verónica; Piraino, Stefano; Kéfi-Daly Yahia, Ons

    2016-01-01

    Jellyfish are of particular concern for marine finfish aquaculture. In recent years repeated mass mortality episodes of farmed fish were caused by blooms of gelatinous cnidarian stingers, as a consequence of a wide range of hemolytic, cytotoxic, and neurotoxic properties of associated cnidocytes venoms. The mauve stinger jellyfish Pelagia noctiluca (Scyphozoa) has been identified as direct causative agent for several documented fish mortality events both in Northern Europe and the Mediterranean Sea aquaculture farms. We investigated the effects of P. noctiluca envenomations on the gilthead sea bream Sparus aurata by in vivo laboratory assays. Fish were incubated for 8 hours with jellyfish at 3 different densities in 300 l experimental tanks. Gill disorders were assessed by histological analyses and histopathological scoring of samples collected at time intervals from 3 hours to 4 weeks after initial exposure. Fish gills showed different extent and severity of gill lesions according to jellyfish density and incubation time, and long after the removal of jellyfish from tanks. Jellyfish envenomation elicits local and systemic inflammation reactions, histopathology and gill cell toxicity, with severe impacts on fish health. Altogether, these results shows P. noctiluca swarms may represent a high risk for Mediterranean finfish aquaculture farms, generating significant gill damage after only a few hours of contact with farmed S. aurata. Due to the growth of the aquaculture sector and the increased frequency of jellyfish blooms in the coastal waters, negative interactions between stinging jellyfish and farmed fish are likely to increase with the potential for significant economic losses. PMID:27100175

  7. Biogeography of jellyfish in the North Atlantic, by traditional and genomic methods

    NASA Astrophysics Data System (ADS)

    Licandro, P.; Blackett, M.; Fischer, A.; Hosia, A.; Kennedy, J.; Kirby, R. R.; Raab, K.; Stern, R.; Tranter, P.

    2015-07-01

    Scientific debate on whether or not the recent increase in reports of jellyfish outbreaks represents a true rise in their abundance has outlined a lack of reliable records of Cnidaria and Ctenophora. Here we describe different jellyfish data sets produced within the EU programme EURO-BASIN. These data were assembled with the aim of creating an improved baseline and providing new data that can be used to evaluate the current diversity and standing stocks of jellyfish in the North Atlantic region. Using a net adapted to sample gelatinous zooplankton quantitatively, cnidarians and ctenophores were collected from the epipelagic layer during spring-summer 2010-2013, in inshore and offshore waters between lat 59 and 68° N and long 62° W and 5° E. Jellyfish were also identified and counted in samples opportunistically collected by other sampling equipment in the same region and at two coastal stations in the Bay of Biscay and in the Gulf of Cadiz. Continuous Plankton Recorder (CPR) samples collected in 2009-2012 were re-analysed with the aim of identifying the time and location of cnidarian blooms across the North Atlantic Basin. Overall the data show high variability in jellyfish abundance and diversity, mainly in relation to different water masses and bathymetry. Higher densities were generally recorded on the shelves, where the communities tend to be more diverse due to the presence of meropelagic medusae. Comparison of net records from the G.O. Sars transatlantic cruise shows that information on jellyfish diversity differs significantly depending on the sampling gear utilised. Indeed, the big trawls mostly collect relatively large scyphozoan and hydrozoan species, while small hydrozoans and early stages of Ctenophora are only caught by smaller nets. Based on CPR data from 2009 to 2012, blooms of cnidarians occurred in all seasons across the whole North Atlantic Basin. Molecular analysis revealed that, contrary to previous hypotheses, the CPR is able to detect

  8. The Victoria (Australia) Certificate of Education (VCE) in Geology for Senior Secondary-School Students.

    ERIC Educational Resources Information Center

    Markovics, Gabor

    1990-01-01

    The state of precollege earth science education in Victoria is described. The unit structure and content for the Victoria Certificate of Education in geology is detailed. The relationship between society and technological development is stressed in this curriculum. (CW)

  9. Environmental Control of Phase Transition and Polyp Survival of a Massive-Outbreaker Jellyfish

    PubMed Central

    Prieto, Laura; Astorga, Diana; Navarro, Gabriel; Ruiz, Javier

    2010-01-01

    A number of causes have been proposed to account for the occurrence of gelatinous zooplankton (both jellyfish and ctenophore) blooms. Jellyfish species have a complex life history involving a benthic asexual phase (polyp) and a pelagic sexual phase (medusa). Strong environmental control of jellyfish life cycles is suspected, but not fully understood. This study presents a comprehensive analysis on the physicochemical conditions that control the survival and phase transition of Cotylorhiza tuberculata; a scyphozoan that generates large outbreaks in the Mediterranean Sea. Laboratory experiments indicated that the influence of temperature on strobilation and polyp survival was the critical factor controlling the capacity of this species to proliferate. Early life stages were less sensitive to other factors such as salinity variations or the competitive advantage provided by zooxanthellae in a context of coastal eutrophication. Coherently with laboratory results, the presence/absence of outbreaks of this jellyfish in a particular year seems to be driven by temperature. This is the first time the environmental forcing of the mechanism driving the life cycle of a jellyfish has been disentangled via laboratory experimentation. Projecting this understanding to a field population under climatological variability results in a pattern coherent with in situ records. PMID:21072185

  10. Environmental control of phase transition and polyp survival of a massive-outbreaker jellyfish.

    PubMed

    Prieto, Laura; Astorga, Diana; Navarro, Gabriel; Ruiz, Javier

    2010-11-03

    A number of causes have been proposed to account for the occurrence of gelatinous zooplankton (both jellyfish and ctenophore) blooms. Jellyfish species have a complex life history involving a benthic asexual phase (polyp) and a pelagic sexual phase (medusa). Strong environmental control of jellyfish life cycles is suspected, but not fully understood. This study presents a comprehensive analysis on the physicochemical conditions that control the survival and phase transition of Cotylorhiza tuberculata; a scyphozoan that generates large outbreaks in the Mediterranean Sea. Laboratory experiments indicated that the influence of temperature on strobilation and polyp survival was the critical factor controlling the capacity of this species to proliferate. Early life stages were less sensitive to other factors such as salinity variations or the competitive advantage provided by zooxanthellae in a context of coastal eutrophication. Coherently with laboratory results, the presence/absence of outbreaks of this jellyfish in a particular year seems to be driven by temperature. This is the first time the environmental forcing of the mechanism driving the life cycle of a jellyfish has been disentangled via laboratory experimentation. Projecting this understanding to a field population under climatological variability results in a pattern coherent with in situ records.

  11. A numerical study of the benefits of driving jellyfish bells at their natural frequency.

    PubMed

    Hoover, Alexander; Miller, Laura

    2015-06-07

    A current question in swimming and flight is whether or not driving flexible appendages at their resonant frequency results in faster or more efficient locomotion. It has been suggested that jellyfish swim faster when the bell is driven at its resonant frequency. The goal of this study was to determine whether or not driving a jellyfish bell at its resonant frequency results in a significant increase in swimming velocity. To address this question, the immersed boundary method was used to solve the fully coupled fluid structure interaction problem of a flexible bell in a viscous fluid. Free vibration numerical experiments were used to determine the resonant frequency of the jellyfish bell. The jellyfish bells were then driven at frequencies ranging from above and below the resonant frequency. We found that jellyfish do swim fastest for a given amount of applied force when the bells are driven near their resonant frequency. Nonlinear effects were observed for larger deformations, shifting the optimal frequency to higher than the resonant frequency. We also found that the benefit of resonant forcing decreases for lower Reynolds numbers.

  12. Extract from the Zooxanthellate Jellyfish Cotylorhiza tuberculata Modulates Gap Junction Intercellular Communication in Human Cell Cultures

    PubMed Central

    Leone, Antonella; Lecci, Raffaella Marina; Durante, Miriana; Piraino, Stefano

    2013-01-01

    On a global scale, jellyfish populations in coastal marine ecosystems exhibit increasing trends of abundance. High-density outbreaks may directly or indirectly affect human economical and recreational activities, as well as public health. As the interest in biology of marine jellyfish grows, a number of jellyfish metabolites with healthy potential, such as anticancer or antioxidant activities, is increasingly reported. In this study, the Mediterranean “fried egg jellyfish” Cotylorhiza tuberculata (Macri, 1778) has been targeted in the search forputative valuable bioactive compounds. A medusa extract was obtained, fractionated, characterized by HPLC, GC-MS and SDS-PAGE and assayed for its biological activity on breast cancer cells (MCF-7) and human epidermal keratinocytes (HEKa). The composition of the jellyfish extract included photosynthetic pigments, valuable ω-3 and ω-6 fatty acids, and polypeptides derived either from jellyfish tissues and their algal symbionts. Extract fractions showed antioxidant activity and the ability to affect cell viability and intercellular communication mediated by gap junctions (GJIC) differentially in MCF-7and HEKa cells. A significantly higher cytotoxicity and GJIC enhancement in MCF-7 compared to HEKa cells was recorded. A putative action mechanism for the anticancer bioactivity through the modulation of GJIC has been hypothesized and its nutraceutical and pharmaceutical potential was discussed. PMID:23697954

  13. Geologic map and structural analysis of the Victoria quadrangle, Mercury

    NASA Astrophysics Data System (ADS)

    Galluzzi, Valentina; Di Achille, Gaetano; Ferranti, Luigi; Rothery, David A.; Palumbo, Pasquale

    2015-04-01

    In this work we present a new geologic map and structural analysis of the Victoria quadrangle (H2) of Mercury, along with a reconnaissance study of the geometry and kinematics of lobate scarps in this area. To this end, we produced a 1:3,000,000 geologic map of the area using the images provided by the NASA spacecraft MESSENGER, which has been orbiting the planet since March, 2011. The geologic map shows the distribution of smooth plains, intermediate plains, intercrater plains units and a classification of crater materials based on an empirical distinction among three stages of degradation. Structural mapping shows that the H2 quadrangle is dominated by N-S faults (here grouped into the Victoria system) to the east and NE-SW faults (Larrocha system) to the west, with the secondary existence of NW-SE-trending faults (Carnegie system) in the north-western area of the quadrangle. A systematic analysis of these systems has led to the following results. 1) the Victoria system is characterized by a main array of faults located along Victoria Rupes - Endeavour Rupes - Antoniadi Dorsum. The segmentation of this array into three different sectors changes from north to south and is spatially linked to the presence of three volcanic vents located at the boundaries between each sector and at the northern end of the Victoria Rupes sector , suggesting that volcanism and faulting are interrelated 2) The main array of Carnegie system is kinematically linked and antithetical to the Victoria system. Both systems have arguably controlled the growth of a longitudinal, fault-free, crustal and gravimetric bulge in the central area of the Victoria quadrangle, which is interpreted as a regional contractional pop-up. 3) The Larrocha system is interrupted against the central bulge and thus is probably older than the Victoria and Carnegie systems. Buffered crater counting performed on the Victoria system confirms the young relative age of its fault segments with respect to the map units

  14. Hazardous thunderstorms over Lake Victoria: climate change and early warnings

    NASA Astrophysics Data System (ADS)

    Thiery, Wim; Davin, Edouard L.; Seneviratne, Sonia I.; Bedka, Kristopher; Lhermitte, Stef; van Lipzig, Nicole

    2016-04-01

    Severe thunderstorms and associated high waves represent a constant threat to the 200,000 fishermen operating on Lake Victoria. According to the International Red Cross, presumably 3000 to 5000 fishermen die every year on the lake, thereby substantially contributing to the global death toll from natural disasters. Despite the long-known bad reputation of Lake Victoria, operational early warning systems are lacking and possible future changes of these extreme thunderstorms are unknown. Here we present the first dedicated high-resolution, coupled lake-land-atmosphere climate projection for the African Great Lakes region and analyse it in combination with new satellite data and coarser-scale ensemble projections. Our model projections for the end-of-the-century indicate that Lake Victoria amplifies the future intensification of extreme precipitation seen over the surrounding land. Under a high-emission scenario (RCP8.5), the 1% most extreme over-lake precipitation may intensify up to four times faster compared to surrounding land. Our findings are consistent with an ensemble of coarser-scale climate projections for Africa, but the lower skill of the ensemble over Lake Victoria constrains its applicability. Interestingly, the change in extremes contrasts to the change in average over-lake precipitation, which is projected to decrease by -6% for the same period. By further analyzing the high-resolution output we are able to explain this different response: while mesoscale circulation changes cause the average precipitation decline, the response of extremes is essentially thermodynamic. Finally, the study of the satellite-based detection of severe thunderstorms revealed a strong dependency of the nighttime storm intensity over Lake Victoria on the antecedent daytime land storm activity. This highlights the potential of this new satellite product for predicting intense storms over Lake Victoria. Overall, our results indicate a new major hazard associated with climate

  15. 78 FR 55215 - Drawbridge Operation Regulation; Old River, Between Victoria Island and Byron Tract, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-10

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Old River, Between Victoria Island... State Highway 4 Drawbridge across Old River, mile 14.8 between Victoria Island and Byron Tract, CA. The..., between Victoria Island and Byron Tract, CA. The drawbridge navigation span provides 12 feet...

  16. 77 FR 61645 - Exelon Generation Company, LLC, Victoria County Station Site; Notice of Withdrawal of Application...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-10

    ... COMMISSION Exelon Generation Company, LLC, Victoria County Station Site; Notice of Withdrawal of Application...) submitted an application for an Early Site Permit (ESP) for the Victoria County Station (VCS) site located in Victoria County, Texas to the U.S. Nuclear Regulatory Commission (NRC or the Commission)...

  17. 40 CFR 81.136 - Corpus Christi-Victoria Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Corpus Christi-Victoria Intrastate Air... Air Quality Control Regions § 81.136 Corpus Christi-Victoria Intrastate Air Quality Control Region. The Corpus Christi-Victoria Intrastate Air Quality Control Region (Texas) consists of the...

  18. 78 FR 65873 - Drawbridge Operation Regulation; Old River, Between Victoria Island and Byron Tract, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-04

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Old River, Between Victoria Island... State Highway 4 Drawbridge across Old River, mile 14.8 between Victoria Island and Byron Tract, CA. The... Highway 4 Drawbridge, mile 14.8, over Old River, between Victoria Island and Byron Tract, CA....

  19. Role of Thyroxine in Space-Developed Jellyfish

    NASA Technical Reports Server (NTRS)

    Spangenberg, Dorothy B.

    1997-01-01

    The Aurelia Metamorphosis Test System was previously used to determine the effects of the space environment on the development and behavior of tiny (1-2 mm) jellyfish ephyrae during the SLS-1 and IML-2 missions. Results from the SLS-1 experiment included the discovery that statolith numbers were significantly reduced in Earth-formed ephyrae flown for nine days in space as compared with ground-based controls. In addition, upon return to Earth, six times more ephyrae which had developed in space than those developed on Earth had pulsing abnormalities, indicating that either these animals did not form their neuromuscular structures normally while in space or they were unable to adapt to the Ig environment upon return to Earth. The metamorphosis process, which enables the formation of ephyrae from polyps is influenced by a hormone, Jf-T4 Oellyfish thyroxine) which is synthesized following iodine administration. Two groups of polyps in space, however, formed ephyrae without iodine administration indicating that Jf-T4 synthesis, utilization, or excretion was different in. the ephyrae. Increased synthesis or build-up in the media of the hormone may also be linked to the increased demineralization of statoliths found in space-exposed ephyrae. In previous experiments, we found that externally administered thyroxine causes increased demineralization of statoliths on Earth. Abnormal pulsina in ephyrae following return to Earth during the SLS-1 mission may also be traced to increased Jf-T4 levels. Thyroxine is known to be important to the normal development and function of the nervous system, heart, and skeletal muscles in higher animals. For this third Jellyfish-in-Space experiment, we proposed to quantitate the levels of Jf- T4 and of T4 receptors in space-developed ephyrae and media and to compare these levels with those of animals developing and at Ig in space and on Earth. We expected to be able to determine whether Jf-T4 synthesis and/or secretion is different in space

  20. Concurrent environmental stressors and jellyfish stings impair caged European sea bass (Dicentrarchus labrax) physiological performances

    PubMed Central

    Bosch-Belmar, Mar; Giomi, Folco; Rinaldi, Alessandro; Mandich, Alberta; Fuentes, Verónica; Mirto, Simone; Sarà, Gianluca; Piraino, Stefano

    2016-01-01

    The increasing frequency of jellyfish outbreaks in coastal areas has led to multiple ecological and socio-economic issues, including mass mortalities of farmed fish. We investigated the sensitivity of the European sea bass (Dicentrarchus labrax), a widely cultured fish in the Mediterranean Sea, to the combined stressors of temperature, hypoxia and stings from the jellyfish Pelagia noctiluca, through measurement of oxygen consumption rates (MO2), critical oxygen levels (PO2crit), and histological analysis of tissue damage. Higher levels of MO2, PO2crit and gill damage in treated fish demonstrated that the synergy of environmental and biotic stressors dramatically impair farmed fish metabolic performances and increase their health vulnerability. As a corollary, in the current scenario of ocean warming, these findings suggest that the combined effects of recurrent hypoxic events and jellyfish blooms in coastal areas might also threaten wild fish populations. PMID:27301314

  1. Giant jellyfish Nemopilema nomurai gathering in the Yellow Sea—a numerical study

    NASA Astrophysics Data System (ADS)

    Wei, Hao; Deng, Lijing; Wang, Yuheng; Zhao, Liang; Li, Xia; Zhang, Fang

    2015-04-01

    A particle tracking model, based on output from the Princeton Ocean Model (POM), is established to study the year-to-year variation of the gathering of giant jellyfish Nemopilema nomurai in early autumn in the Yellow Sea. Particles standing for scyphistoma adhered to the bottom are put initially along the coast from the Changjiang River estuary to Haizhou Bay. The triggering temperature for scyphistoma strobilation is set to 13 °C. The simulated N. nomurai distribution is in good agreement with observations in August 2009. Model results suggest that more jellyfish gathered near tidal front in August-September of 2008 than during the same period of 2009. Using a set of sensitivity experiments, the influences of temperature and circulation on N. nomurai gathering are discussed. Model results suggest the modeled difference in fall gathering of jellyfish between 2008 and 2009 can be attributed more to changes in circulation than the triggering of strobilation by spring bottom temperature.

  2. Room temperature spectrally resolved single-molecule spectroscopy reveals new spectral forms and photophysical versatility of aequorea green fluorescent protein variants.

    PubMed

    Blum, Christian; Meixner, Alfred J; Subramaniam, Vinod

    2004-12-01

    It is known from ensemble spectroscopy at cryogenic temperatures that variants of the Aequorea green fluorescent protein (GFP) occur in interconvertible spectroscopically distinct forms which are obscured in ensemble room temperature spectroscopy. By analyzing the fluorescence of the GFP variants EYFP and EGFP by spectrally resolved single-molecule spectroscopy we were able to observe spectroscopically different forms of the proteins and to dynamically monitor transitions between these forms at room temperature. In addition to the predominant EYFP B-form we have observed the blue-shifted I-form thus far only seen at cryogenic temperatures and have followed transitions between these forms. Further we have identified for EYFP and for EGFP three more, so far unknown, forms with red-shifted fluorescence. Transitions between the predominant forms and the red-shifted forms show a dark time which indicates the existence of a nonfluorescent intermediate. The spectral position of the newly-identified red-shifted forms and their formation via a nonfluorescent intermediate hint that these states may account for the possible photoactivation observed in bulk experiments. The comparison of the single-protein spectra of the red-shifted EYFP and EGFP forms with single-molecule fluorescence spectra of DsRed suggest that these new forms possibly originate from an extended chromophoric pi-system analogous to the DsRed chromophore.

  3. Jellyfish extract induces apoptotic cell death through the p38 pathway and cell cycle arrest in chronic myelogenous leukemia K562 cells

    PubMed Central

    Kwak, Choong-Hwan; Abekura, Fukushi; Park, Jun-Young; Park, Nam Gyu; Chang, Young-Chae; Lee, Young-Choon; Chung, Tae-Wook; Ha, Ki-Tae; Son, Jong-Keun

    2017-01-01

    Jellyfish species are widely distributed in the world’s oceans, and their population is rapidly increasing. Jellyfish extracts have several biological functions, such as cytotoxic, anti-microbial, and antioxidant activities in cells and organisms. However, the anti-cancer effect of Jellyfish extract has not yet been examined. We used chronic myelogenous leukemia K562 cells to evaluate the mechanisms of anti-cancer activity of hexane extracts from Nomura’s jellyfish in vitro. In this study, jellyfish are subjected to hexane extraction, and the extract is shown to have an anticancer effect on chronic myelogenous leukemia K562 cells. Interestingly, the present results show that jellyfish hexane extract (Jellyfish-HE) induces apoptosis in a dose- and time-dependent manner. To identify the mechanism(s) underlying Jellyfish-HE-induced apoptosis in K562 cells, we examined the effects of Jellyfish-HE on activation of caspase and mitogen-activated protein kinases (MAPKs), which are responsible for cell cycle progression. Induction of apoptosis by Jellyfish-HE occurred through the activation of caspases-3,-8 and -9 and phosphorylation of p38. Jellyfish-HE-induced apoptosis was blocked by a caspase inhibitor, Z-VAD. Moreover, during apoptosis in K562 cells, p38 MAPK was inhibited by pretreatment with SB203580, an inhibitor of p38. SB203580 blocked jellyfish-HE-induced apoptosis. Additionally, Jellyfish-HE markedly arrests the cell cycle in the G0/G1 phase. Therefore, taken together, the results imply that the anti-cancer activity of Jellyfish-HE may be mediated apoptosis by induction of caspases and activation of MAPK, especially phosphorylation of p38, and cell cycle arrest at the Go/G1 phase in K562 cells. PMID:28133573

  4. Protective Effect of Tetracycline against Dermal Toxicity Induced by Jellyfish Venom

    PubMed Central

    Kang, Changkeun; Jin, Yeung Bae; Kwak, Jeongsoo; Jung, Hongseok; Yoon, Won Duk; Yoon, Tae-Jin; Kim, Jong-Shu; Kim, Euikyung

    2013-01-01

    Background Previously, we have reported that most, if not all, of the Scyphozoan jellyfish venoms contain multiple components of metalloproteinases, which apparently linked to the venom toxicity. Further, it is also well known that there is a positive correlation between the inflammatory reaction of dermal tissues and their tissue metalloproteinase activity. Based on these, the use of metalloproteinase inhibitors appears to be a promising therapeutic alternative for the treatment of jellyfish envenomation. Methodology and Principal Findings Tetracycline (a metalloproteinase inhibitor) has been examined for its activity to reduce or prevent the dermal toxicity induced by Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom (NnV) using in vitro and in vivo models. HaCaT (human keratinocyte) and NIH3T3 (mouse fibroblast) incubated with NnV showed decreases in cell viability, which is associated with the inductions of metalloproteinase-2 and -9. This result suggests that the use of metalloproteinase inhibitors, such as tetracycline, may prevent the jellyfish venom-mediated local tissue damage. In vivo experiments showed that comparing with NnV-alone treatment, tetracycline pre-mixed NnV demonstrated a significantly reduced progression of dermal toxicity upon the inoculation onto rabbit skin. Conclusions/Significance It is believed that there has been no previous report on the therapeutic agent of synthetic chemical origin for the treatment of jellyfish venom-induced dermonecrosis based on understanding its mechanism of action except the use of antivenom treatment. Furthermore, the current study, for the first time, has proposed a novel mechanism-based therapeutic intervention for skin damages caused by jellyfish stings. PMID:23536767

  5. Statolith Morphometrics Can Discriminate among Taxa of Cubozoan Jellyfishes

    PubMed Central

    Kingsford, Michael J.

    2016-01-01

    Identification of potentially harmful cubomedusae is difficult due to their gelatinous nature. The only hard structure of medusae, the statolith, has the potential to provide robust measurements for morphometric analysis. Traditional morphometric length to width ratios (L: W) and modern morphometric Elliptical Fourier Analysis (EFA) were applied to proximal, oral and lateral statolith faces of 12 cubozoan species. EFA outperformed L: W as L: W did not account for the curvature of the statolith. Best discrimination was achieved with Canonical Discriminant Analysis (CDA) when analysing proximal + oral + lateral statolith faces in combination. Normalised Elliptical Fourier (NEF) coefficients classified 98% of samples to their correct species and 94% to family group. Statolith shape agreed with currently accepted cubozoan taxonomy. This has potential to assist in identifying levels of risk and stock structure of populations in areas where box jellyfish envenomations are a concern as the severity of envenomation is family dependent. We have only studied 12 (27%) of the 45 currently accepted cubomedusae, but analyses demonstrated that statolith shape is an effective taxonomic discriminator within the Class. PMID:27192408

  6. Stable hovering of a jellyfish-like flying machine

    PubMed Central

    Ristroph, Leif; Childress, Stephen

    2014-01-01

    Ornithopters, or flapping-wing aircraft, offer an alternative to helicopters in achieving manoeuvrability at small scales, although stabilizing such aerial vehicles remains a key challenge. Here, we present a hovering machine that achieves self-righting flight using flapping wings alone, without relying on additional aerodynamic surfaces and without feedback control. We design, construct and test-fly a prototype that opens and closes four wings, resembling the motions of swimming jellyfish more so than any insect or bird. Measurements of lift show the benefits of wing flexing and the importance of selecting a wing size appropriate to the motor. Furthermore, we use high-speed video and motion tracking to show that the body orientation is stable during ascending, forward and hovering flight modes. Our experimental measurements are used to inform an aerodynamic model of stability that reveals the importance of centre-of-mass location and the coupling of body translation and rotation. These results show the promise of flapping-flight strategies beyond those that directly mimic the wing motions of flying animals. PMID:24430122

  7. Pore Water Pumping by Upside-Down Jellyfish

    NASA Astrophysics Data System (ADS)

    Gaddam, Manikantam; Santhanakrishnan, Arvind

    2016-11-01

    Patchy aggregations of Cassiopea medusae, commonly called upside-down jellyfish, are found in sheltered marine environments with low-speed ambient flows. These medusae exhibit a sessile, non-swimming lifestyle, and are oriented such that their bells are attached to the substrate and oral arms point towards sunlight. Pulsations of their bells are used to generate currents for suspension feeding. Their pulsations have also been proposed to generate forces that can release sediment locked nutrients into the surrounding water. The goal of this study is to examine pore water pumping by Cassiopea individuals in laboratory aquaria, as a model for understanding pore water pumping in unsteady flows. Planar laser-induced fluorescence (PLIF) measurements were conducted to visualize the release of pore water via bell motion, using fluorescent dye introduced underneath the substrate. 2D particle image velocimetry (PIV) measurements were conducted on the same individuals to correlate PLIF-based concentration profiles with the jets generated by pulsing of medusae. The effects of varying bell diameter on pore water release and pumping currents will be discussed.

  8. Stable hovering of a jellyfish-like flying machine.

    PubMed

    Ristroph, Leif; Childress, Stephen

    2014-03-06

    Ornithopters, or flapping-wing aircraft, offer an alternative to helicopters in achieving manoeuvrability at small scales, although stabilizing such aerial vehicles remains a key challenge. Here, we present a hovering machine that achieves self-righting flight using flapping wings alone, without relying on additional aerodynamic surfaces and without feedback control. We design, construct and test-fly a prototype that opens and closes four wings, resembling the motions of swimming jellyfish more so than any insect or bird. Measurements of lift show the benefits of wing flexing and the importance of selecting a wing size appropriate to the motor. Furthermore, we use high-speed video and motion tracking to show that the body orientation is stable during ascending, forward and hovering flight modes. Our experimental measurements are used to inform an aerodynamic model of stability that reveals the importance of centre-of-mass location and the coupling of body translation and rotation. These results show the promise of flapping-flight strategies beyond those that directly mimic the wing motions of flying animals.

  9. Statolith Morphometrics Can Discriminate among Taxa of Cubozoan Jellyfishes.

    PubMed

    Mooney, Christopher J; Kingsford, Michael J

    2016-01-01

    Identification of potentially harmful cubomedusae is difficult due to their gelatinous nature. The only hard structure of medusae, the statolith, has the potential to provide robust measurements for morphometric analysis. Traditional morphometric length to width ratios (L: W) and modern morphometric Elliptical Fourier Analysis (EFA) were applied to proximal, oral and lateral statolith faces of 12 cubozoan species. EFA outperformed L: W as L: W did not account for the curvature of the statolith. Best discrimination was achieved with Canonical Discriminant Analysis (CDA) when analysing proximal + oral + lateral statolith faces in combination. Normalised Elliptical Fourier (NEF) coefficients classified 98% of samples to their correct species and 94% to family group. Statolith shape agreed with currently accepted cubozoan taxonomy. This has potential to assist in identifying levels of risk and stock structure of populations in areas where box jellyfish envenomations are a concern as the severity of envenomation is family dependent. We have only studied 12 (27%) of the 45 currently accepted cubomedusae, but analyses demonstrated that statolith shape is an effective taxonomic discriminator within the Class.

  10. Box Jellyfish Alatina alata Has a Circumtropical Distribution.

    PubMed

    Lawley, Jonathan W; Ames, Cheryl Lewis; Bentlage, Bastian; Yanagihara, Angel; Goodwill, Roger; Kayal, Ehsan; Hurwitz, Kikiana; Collins, Allen G

    2016-10-01

    Species of the box jellyfish (Cubozoa) genus Alatina are notorious for their sting along the beaches of several localities of the Atlantic and Pacific. These species include Alatina alata on the Caribbean Island of Bonaire (the Netherlands), A. moseri in Hawaii, and A. mordens in Australia. Most cubozoans inhabit coastal waters, but Alatina is unusual in that specimens have also been collected in the open ocean at great depths. Alatina is notable in that populations form monthly aggregations for spermcast mating in conjunction with the lunar cycle. Nominal species are difficult to differentiate morphologically, and it has been unclear whether they are distinct or a single species with worldwide distribution. Here we report the results of a population genetic study, using nuclear and mitochondrial sequence data from four geographical localities. Our analyses revealed a general lack of geographic structure among Alatina populations, and slight though significant isolation by distance. These data corroborate morphological and behavioral similarities observed in the geographically disparate localities, and indicate the presence of a single, pantropically distributed species, Alatina alata. While repeated, human-mediated introductions of A. alata could explain the patterns we have observed, it seems more likely that genetic metapopulation cohesion is maintained via dispersal through the swimming medusa stage, and perhaps via dispersal of encysted planulae, which are described here for the first time in Alatina.

  11. Faking giants: the evolution of high prey clearance rates in jellyfishes.

    PubMed

    Acuña, José Luis; López-Urrutia, Ángel; Colin, Sean

    2011-09-16

    Jellyfishes have functionally replaced several overexploited commercial stocks of planktivorous fishes. This is paradoxical, because they use a primitive prey capture mechanism requiring direct contact with the prey, whereas fishes use more efficient visual detection. We have compiled published data to show that, in spite of their primitive life-style, jellyfishes exhibit similar instantaneous prey clearance and respiration rates as their fish competitors and similar potential for growth and reproduction. To achieve this production, they have evolved large, water-laden bodies that increase prey contact rates. Although larger bodies are less efficient for swimming, optimization analysis reveals that large collectors are advantageous if they move through the water sufficiently slowly.

  12. Biogeography of jellyfish in the North Atlantic, by traditional and genomic methods

    NASA Astrophysics Data System (ADS)

    Licandro, P.; Blackett, M.; Fischer, A.; Hosia, A.; Kennedy, J.; Kirby, R. R.; Raab, K.; Stern, R.; Tranter, P.

    2014-11-01

    Scientific debate on whether the recent increase in reports of jellyfish outbreaks is related to a true rise in their abundance, have outlined the lack of reliable records of Cnidaria and Ctenophora. Here we describe different data sets produced within the EU program EUROBASIN, which have been assembled with the aim of presenting an up to date overview of the diversity and standing stocks of jellyfish in the North Atlantic region. Using a net adapted to sample gelatinous zooplankton quantitatively, Cnidaria and Ctenophora were collected in the epipelagic layer during spring-summer 2010-2013, in inshore and offshore waters between 59-68° N Lat and 62° W-5° E Long. Jellyfish were also identified and counted in samples opportunistically collected by other sampling equipment in the same region and at two coastal stations in the Bay of Biscay and in the Gulf of Cadiz. Continuous Plankton Recorder (CPR) samples collected in 2009-2012 were re-analysed with the aim of identifying the time and location of Cnidarian blooms across the North Atlantic basin. Overall the data show high variability in jellyfish abundance and diversity, mainly in relation with different water masses and with the bathymetry. Higher densities were generally recorded on the shelves, where populations tend to be more diversified due to the presence of meropelagic medusae. Comparisons of net records from the G.O. Sars transatlantic cruise show that information on jellyfish diversity differs significantly depending on the sampling gear utilised. Indeed, the big trawls mostly collect relatively large scyphozoan and hydrozoan species, while small hydrozoans and early stages of ctenophora are only caught by smaller nets. Based on CPR data from 2009-2012, blooms of Cnidarians occurred in all seasons across the whole North Atlantic basin. Molecular analysis revealed that, in contrast with what was previously hypothesized, the CPR is able to detect blooms of meroplanktonic and holoplanktonic hydrozoans and

  13. Surfactant-laden drop jellyfish-breakup mode induced by the Marangoni effect

    NASA Astrophysics Data System (ADS)

    Zhao, Hui; Zhang, Wen-Bin; Xu, Jian-Liang; Li, Wei-Feng; Liu, Hai-Feng

    2017-03-01

    Drop breakup is a familiar event in both nature and technology. In this study, we find that the bag breakup mode can be replaced by a new breakup mode: jellyfish breakup, when the surfactant concentration of a surfactant-laden drop is high. This new breakup mode has a morphology resembling a jellyfish with many long tentacles. This is due to the inhomogeneous distribution of surfactant in the process of drop deformation and breakup. The thin film of liquid can remain stable as a result of the Marangoni effect. Finally, we propose that the dimensionless surfactant concentration can serve as a criterion for breakup mechanisms.

  14. Epilithic lichens in the Beacon sandstone formation, Victoria Land, Antarctica

    NASA Technical Reports Server (NTRS)

    Hale, M. E.; Friedmann, E. I. (Principal Investigator)

    1987-01-01

    The epilithic lichen flora on the Beacon sandstone formation in Victoria Land consists of seven species: Acarospora gwynnii Dodge & Rudolph, Buellia grisea Dodge & Baker, B. pallida Dodge & Baker, Carbonea capsulata (Dodge & Baker) Hale comb. nov., Lecanora fuscobrunnea Dodge & Baker, Lecidea cancriformis Dodge & Baker, and L. siplei Dodge & Baker. The typification of the species is given along with descriptions and distribution in Antarctica.

  15. Persistence of neutral polymorphisms in Lake Victoria cichlid fish

    PubMed Central

    Nagl, Sandra; Tichy, Herbert; Mayer, Werner E.; Takahata, Naoyuki; Klein, Jan

    1998-01-01

    Phylogenetic trees for groups of closely related species often have different topologies, depending on the genes used. One explanation for the discordant topologies is the persistence of polymorphisms through the speciation phase, followed by differential fixation of alleles in the resulting species. The existence of transspecies polymorphisms has been documented for alleles maintained by balancing selection but not for neutral alleles. In the present study, transspecific persistence of neutral polymorphisms was tested in the endemic haplochromine species flock of Lake Victoria cichlid fish. Putative noncoding region polymorphisms were identified at four randomly selected nuclear loci and tested on a collection of 12 Lake Victoria species and their putative riverine ancestors. At all loci, the same polymorphism was found to be present in nearly all the tested species, both lacustrine and riverine. Different polymorphisms at these loci were found in cichlids of other East African lakes (Malawi and Tanganyika). The Lake Victoria polymorphisms must have therefore arisen after the flocks now inhabiting the three great lakes diverged from one another, but before the riverine ancestors of the Lake Victoria flock colonized the Lake. Calculations based on the mtDNA clock suggest that the polymorphisms have persisted for about 1.4 million years. To maintain neutral polymorphisms for such a long time, the population size must have remained large throughout the entire period. PMID:9826684

  16. Persistence of neutral polymorphisms in Lake Victoria cichlid fish.

    PubMed

    Nagl, S; Tichy, H; Mayer, W E; Takahata, N; Klein, J

    1998-11-24

    Phylogenetic trees for groups of closely related species often have different topologies, depending on the genes used. One explanation for the discordant topologies is the persistence of polymorphisms through the speciation phase, followed by differential fixation of alleles in the resulting species. The existence of transspecies polymorphisms has been documented for alleles maintained by balancing selection but not for neutral alleles. In the present study, transspecific persistence of neutral polymorphisms was tested in the endemic haplochromine species flock of Lake Victoria cichlid fish. Putative noncoding region polymorphisms were identified at four randomly selected nuclear loci and tested on a collection of 12 Lake Victoria species and their putative riverine ancestors. At all loci, the same polymorphism was found to be present in nearly all the tested species, both lacustrine and riverine. Different polymorphisms at these loci were found in cichlids of other East African lakes (Malawi and Tanganyika). The Lake Victoria polymorphisms must have therefore arisen after the flocks now inhabiting the three great lakes diverged from one another, but before the riverine ancestors of the Lake Victoria flock colonized the Lake. Calculations based on the mtDNA clock suggest that the polymorphisms have persisted for about 1.4 million years. To maintain neutral polymorphisms for such a long time, the population size must have remained large throughout the entire period.

  17. Vocabulary Size Research at Victoria University of Wellington, New Zealand

    ERIC Educational Resources Information Center

    Nation, Paul; Coxhead, Averil

    2014-01-01

    The English Language Institute (now the School of Linguistics and Applied Language Studies) at Victoria University of Wellington has a long history of corpus-based vocabulary research, especially after the arrival of the second director of the institute, H. V. George, and the appointment of Helen Barnard, whom George knew in India. George's…

  18. The Free Kindergarten Union of Victoria, 1908-80.

    ERIC Educational Resources Information Center

    Gardiner, Lyndsay

    The social history of the Free Kindergarten Union of the State of Victoria, Australia, from inception in 1908 to the year 1980 is recorded in this book. Growth of the union is described within the context of the World Wars, the Depression, and urbanization and industrialization. The story begins with volunteerism and philanthropy, and with four…

  19. Molecular epidemiology and phylogeography of Schistosoma mansoni around Lake Victoria.

    PubMed

    Standley, C J; Kabatereine, N B; Lange, C N; Lwambo, N J S; Stothard, J R

    2010-11-01

    Intestinal schistosomiasis continues to be a major public health problem in sub-Saharan Africa, and is endemic in communities around Lake Victoria. Interest is growing in the molecular evolution and population genetic structure of Schistosoma mansoni and we describe a detailed analysis of the molecular epidemiology and phylogeography of S. mansoni from Lake Victoria. In total, 388 cytochrome oxidase 1 (COI) sequences were obtained from 25 sites along the Ugandan, Tanzanian and Kenyan shorelines of Lake Victoria, and 122 unique barcodes were identified; 9 corresponded to previously discovered barcodes from Lakes Victoria and Albert. A subset of the data, composed of COI sequences from miracidia from 10 individual children, was used for population genetics analyses; these results were corroborated by microsatellite analysis of 4 isolates of lab-passaged adult worms. Overall, 12 barcodes were found to be shared across all 3 countries, whereas the majority occurred singly and were locally restricted. The population genetics analyses were in agreement in revealing high diversity at the level of the human host and negligible population structuring by location. The lack of correlation between genetic distance and geographical distance in these data may be attributed to the confounding influence of high intra-individual diversity as well as human migration between communities.

  20. Catalogue Use at the State Library of Victoria

    ERIC Educational Resources Information Center

    Hider, Philip

    2008-01-01

    A questionnaire survey conducted at the State Library of Victoria indicates that users in general, and not just scholars, value the standard elements of bibliographic data found in the Library's catalogues, and consider all these elements useful for finding, identifying and selecting items. Rather than making do with less, users wanted more…

  1. Reaching Year 12 in Victoria, Australia: Student and School Influences

    ERIC Educational Resources Information Center

    Marks, Gary

    2014-01-01

    This paper examines student and school influences on reaching Year 12, the final year of schooling in Victoria, Australia. It analyses data from the population of students who were in Year 9 in 2008. Male, English-speaking background, government school, and especially Indigenous students were less likely to reach Year 12 than comparison groups.…

  2. Information Brokers in Victoria: Doing What, for Whom and How.

    ERIC Educational Resources Information Center

    Broadbent, Marianne; Kelson, Deborah

    1984-01-01

    Reports findings of study of information brokers in Victoria, Australia, which identified services offered by individual brokers and information brokerage businesses, resources used to provide those services, their clientele and pricing strategies, the attributes needed for a successful broker, and relationships between brokers and traditional…

  3. Advances in fluorescent protein technology.

    PubMed

    Shaner, Nathan C; Patterson, George H; Davidson, Michael W

    2007-12-15

    Current fluorescent protein (FP) development strategies are focused on fine-tuning the photophysical properties of blue to yellow variants derived from the Aequorea victoria jellyfish green fluorescent protein (GFP) and on the development of monomeric FPs from other organisms that emit in the yellow-orange to far-red regions of the visible light spectrum. Progress toward these goals has been substantial, and near-infrared emitting FPs may loom over the horizon. The latest efforts in jellyfish variants have resulted in new and improved monomeric BFP, CFP, GFP and YFP variants, and the relentless search for a bright, monomeric and fast-maturing red FP has yielded a host of excellent candidates, although none is yet optimal for all applications. Meanwhile, photoactivatable FPs are emerging as a powerful class of probes for intracellular dynamics and, unexpectedly, as useful tools for the development of superresolution microscopy applications.

  4. Rapid scavenging of jellyfish carcasses reveals the importance of gelatinous material to deep-sea food webs

    PubMed Central

    Sweetman, Andrew K.; Smith, Craig R.; Dale, Trine; Jones, Daniel O. B.

    2014-01-01

    Jellyfish blooms are common in many oceans, and anthropogenic changes appear to have increased their magnitude in some regions. Although mass falls of jellyfish carcasses have been observed recently at the deep seafloor, the dense necrophage aggregations and rapid consumption rates typical for vertebrate carrion have not been documented. This has led to a paradigm of limited energy transfer to higher trophic levels at jelly falls relative to vertebrate organic falls. We show from baited camera deployments in the Norwegian deep sea that dense aggregations of deep-sea scavengers (more than 1000 animals at peak densities) can rapidly form at jellyfish baits and consume entire jellyfish carcasses in 2.5 h. We also show that scavenging rates on jellyfish are not significantly different from fish carrion of similar mass, and reveal that scavenging communities typical for the NE Atlantic bathyal zone, including the Atlantic hagfish, galatheid crabs, decapod shrimp and lyssianasid amphipods, consume both types of carcasses. These rapid jellyfish carrion consumption rates suggest that the contribution of gelatinous material to organic fluxes may be seriously underestimated in some regions, because jelly falls may disappear much more rapidly than previously thought. Our results also demonstrate that the energy contained in gelatinous carrion can be efficiently incorporated into large numbers of deep-sea scavengers and food webs, lessening the expected impacts (e.g. smothering of the seafloor) of enhanced jellyfish production on deep-sea ecosystems and pelagic–benthic coupling. PMID:25320167

  5. Rapid scavenging of jellyfish carcasses reveals the importance of gelatinous material to deep-sea food webs.

    PubMed

    Sweetman, Andrew K; Smith, Craig R; Dale, Trine; Jones, Daniel O B

    2014-12-07

    Jellyfish blooms are common in many oceans, and anthropogenic changes appear to have increased their magnitude in some regions. Although mass falls of jellyfish carcasses have been observed recently at the deep seafloor, the dense necrophage aggregations and rapid consumption rates typical for vertebrate carrion have not been documented. This has led to a paradigm of limited energy transfer to higher trophic levels at jelly falls relative to vertebrate organic falls. We show from baited camera deployments in the Norwegian deep sea that dense aggregations of deep-sea scavengers (more than 1000 animals at peak densities) can rapidly form at jellyfish baits and consume entire jellyfish carcasses in 2.5 h. We also show that scavenging rates on jellyfish are not significantly different from fish carrion of similar mass, and reveal that scavenging communities typical for the NE Atlantic bathyal zone, including the Atlantic hagfish, galatheid crabs, decapod shrimp and lyssianasid amphipods, consume both types of carcasses. These rapid jellyfish carrion consumption rates suggest that the contribution of gelatinous material to organic fluxes may be seriously underestimated in some regions, because jelly falls may disappear much more rapidly than previously thought. Our results also demonstrate that the energy contained in gelatinous carrion can be efficiently incorporated into large numbers of deep-sea scavengers and food webs, lessening the expected impacts (e.g. smothering of the seafloor) of enhanced jellyfish production on deep-sea ecosystems and pelagic-benthic coupling.

  6. Distribution of moon jellyfish Aurelia aurita in relation to summer hypoxia in Hiroshima Bay, Seto Inland Sea

    NASA Astrophysics Data System (ADS)

    Shoji, Jun; Kudoh, Takaya; Takatsuji, Hideyuki; Kawaguchi, Osamu; Kasai, Akihide

    2010-02-01

    Biological and physical surveys were conducted in order to investigate the relationship between environmental conditions and the distribution of moon jellyfish Aurelia aurita in Hiroshima Bay, western Seto Inland Sea, Japan. Moon jellyfish and ichthyoplankton were collected at 13 stations in Hiroshima Bay during monthly surveys from July to September in 2006 and 2007. Surface temperature in 2006 was significantly lower during the August and September cruises and surface salinity was lower during all cruises than in 2007. Moon jellyfish was the most dominant gelatinous plankton collected, accounting for 89.7% in wet weight. Mean moon jellyfish abundance in 2006 was higher than that in 2007 from July through September, with significant inter-year differences for July and September. Variability in precipitation and nutritional input from the Ohta River, northernmost part of Hiroshima Bay, were suggested as possible factors affecting the inter-annual variability in moon jellyfish abundance in the coastal areas of northern Hiroshima Bay. Moon jellyfish were more abundant in the coastal areas of northern Hiroshima Bay, where the dissolved oxygen (DO) concentration was lower, while low in the central part of the bay. Japanese anchovy Engraulis japonicus eggs were most dominant (58.1% in number) among the ichthyoplankton and were abundant in the central area of Hiroshima Bay. Explanatory analysis was conducted to detect possible effects of environmental conditions on the abundance of moon jellyfish and Japanese anchovy eggs during the summer months in Hiroshima Bay. Of the environmental conditions tested (temperature, salinity and DO of surface and bottom layers at each sampling station), bottom DO had the most significant effect on the moon jellyfish abundance: there was a negative correlation between the bottom DO and the moon jellyfish abundance in Hiroshima Bay during summer.

  7. An analysis of dynamical factors influencing 2013 giant jellyfish bloom near Qinhuangdao in the Bohai Sea, China∗

    NASA Astrophysics Data System (ADS)

    Wu, Lingjuan; Wang, Jia; Gao, Song; Zheng, Xiangrong; Huang, Rui

    2017-02-01

    The explosive growth of Nemopilema nomurai occurred near the coastal waters of Qinhuangdao in July 2013. However, it did not take place in 2012. In this paper, the dynamical factors of wind, ocean current and sea temperature on giant jellyfish bloom in 2013 is analyzed by a comprehensive investigation. The numerical experiments are based on a numerical trajectory model of the jellyfish particles, which are released into the waters from Feiyan Shoal to New Yellow River Mouth, where is speculated as the most likely remote source of Qinhuangdao jellyfish bloom. The results show that in surface layer the jellyfish drift is jointly driven by the surface wind and surface current. For example, in northeastern Bohai Bay, the giant jellyfish moved northwestward in surface layer with influence of the westward wind and current anomalies during the second half of May in 2013, then approached the south of Jingtang Port by early June, and accumulated near Qinhuangdao in early July. The 2012 scenario during the same period was quite different. The jellyfish particles influencing waters near Qinhuangdao decreased with depth and there was few (no) particles influencing Qinhuangdao in middle (bottom) layer because the anticyclonic residual circulation weakened with depth in Bohai Bay. Besides, in the potential source waters of jellyfish, sea temperature in 2012 was more suitable for jellyfish bloom than that in 2013 if there was adequate bait. Hence, the specified direction of wind and current pattern in the Bohai Sea in surface layer (especially in the northeastern Bohai Bay during the second half of May) was more important for jellyfish bloom near Qinhuangdao than the sea temperature in the potential source.

  8. [Effects of macro-jellyfish abundance dynamics on fishery resource structure in the Yangtze River estuary and its adjacent waters].

    PubMed

    Shan, Xiu-Juan; Zhuang, Zhi-Meng; Jin, Xian-Shi; Dai, Fang-Qun

    2011-12-01

    Based on the bottom trawl survey data in May 2007 and May and June 2008, this paper analyzed the effects of the abundance dynamics of macro-jellyfish on the species composition, distribution, and abundance of fishery resource in the Yangtze River estuary and its adjacent waters. From May 2007 to June 2008, the average catch per haul and the top catch per haul of macro-jellyfish increased, up to 222.2 kg x h(-1) and 1800 kg x h(-1) in June 2008, respectively. The macro-jellyfish were mainly distributed in the areas around 50 m isobath, and not beyond 100 m isobath where was the joint front of the coastal waters of East China Sea, Yangtze River runoff, and Taiwan Warm Current. The main distribution area of macro-jellyfish in June migrated northward, as compared with that in May, and the highest catches of macro-jellyfish in May 2007 and May 2008 were found in the same sampling station (122.5 degrees E, 28.5 degrees N). In the sampling stations with higher abundance of macro-jellyfish, the fishery abundance was low, and the fishery species also changed greatly, mainly composed by small-sized species (Trachurus japonicus, Harpadon nehereus, and Acropoma japonicum) and pelagic species (Psenopsis anomala, Octopus variabilis) and Trichiurus japonicus, and P. anomala accounted for 23.7% of the total catch in June 2008. Larimichthys polyactis also occupied higher proportion of the total catch in sampling stations with higher macro-jellyfish abundance, but the demersal species Lophius litulon was not found, and a few crustaceans were collected. This study showed that macro-jellyfish had definite negative effects on the fishery community structure and abundance in the Yangtze River estuary fishery ecosystem, and further, changed the energy flow patterns of the ecosystem through cascading trophic interactions. Therefore, macro-jellyfish was strongly suggested to be an independent ecological group when the corresponding fishery management measures were considered.

  9. Isolation, Characterization and Evaluation of Collagen from Jellyfish Rhopilema esculentum Kishinouye for Use in Hemostatic Applications

    PubMed Central

    Cheng, Xiaochen; Liu, Chenguang

    2017-01-01

    Hemostat has been a crucial focus since human body is unable to control massive blood loss, and collagen proves to be an effective hemostat in previous studies. In this study, collagen was isolated from the mesoglea of jellyfish Rhopilema esculentum Kishinouye and its hemostatic property was studied. The yields of acid-soluble collagen (ASC) and pepsin-soluble (PSC) were 0.12% and 0.28% respectively. The SDS-PAGE patterns indicated that the collagen extracted from jellyfish mesoglea was type I collagen. The lyophilized jellyfish collagen sponges were cross-linked with EDC and interconnected networks in the sponges were revealed by scanning electron microscope (SEM). Collagen sponges exhibited higher water absorption rates than medical gauze and EDC/NHS cross-linking method could improve the stability of the collagen sponges. Compared with medical gauze groups, the blood clotting indexes (BCIs) of collagen sponges were significantly decreased (P < 0.05) and the concentration of collagen also had an influence on the hemostatic property (P < 0.05). Collagen sponges had an improved hemostatic ability compared to the gauze control in tail amputation rat models. Hemostatic mechanism studies showed that hemocytes and platelets could adhere and aggregate on the surface of collagen sponge. All properties make jellyfish collagen sponge to be a suitable candidate used as hemostatic material and for wound healing applications. PMID:28103327

  10. Geographic patterns of fishes and jellyfish in Puget Sound surface waters

    USGS Publications Warehouse

    Rice, Casimir A.; Duda, Jeffrey J.; Greene, Correigh M.; Karr, James R.

    2012-01-01

    We explored patterns of small pelagic fish assemblages and biomass of gelatinous zooplankton (jellyfish) in surface waters across four oceanographic subbasins of greater Puget Sound. Our study is the first to collect data documenting biomass of small pelagic fishes and jellyfish throughout Puget Sound; sampling was conducted opportunistically as part of a juvenile salmon survey of daytime monthly surface trawls at 52 sites during May–August 2003. Biomass composition differed spatially and temporally, but spatial differences were more distinct. Fish dominated in the two northern basins of Puget Sound, whereas jellyfish dominated in the two southern basins. Absolute and relative abundance of jellyfish, hatchery Chinook salmon Oncorhynchus tshawytscha, and chum salmon O. keta decreased with increasing latitude, whereas the absolute and relative abundance of most fish species and the average fish species richness increased with latitude. The abiotic factors with the strongest relationship to biomass composition were latitude, water clarity, and sampling date. Further study is needed to understand the spatial and temporal heterogeneity in the taxonomic composition we observed in Puget Sound surface waters, especially as they relate to natural and anthropogenic influences.

  11. Studying large jellyfish swimming hydrodynamics using a biomimetic robot named Cyro 2

    NASA Astrophysics Data System (ADS)

    Stewart, Colin; Krummel, Gregory; Villanueva, Alex; Marut, Kenneth; Priya, Shashank

    2015-11-01

    Some species of jellyfish can grow to great sizes, such as the lion's mane jellyfish (Cyanea capillata), which can span 2 m in diameter with tentacles 30 m long, roughly the same length as a blue whale. This is an impressive feat for an animal that begins its mobile life three orders of magnitude smaller. Such growth can require a large energy budget, suggesting that Cyanea may be a uniquely efficient swimmer, successful predator, or both. Either accolade would stem from a high level of hydrodynamic mastery as oblate jellyfish like Cyanea rely on the flow currents generated by bell pulsation for both propulsive thrust and prey encounter. However, further investigation has been hindered by the lack of reported quantitative flow measurements, perhaps due to the logistic challenges inherent to studying large specimen in vivo. Here, we used a 50 cm diameter biomimetic Cyanea robot named Cyro 2 as a proxy to study the hydrodynamics of large jellyfish. The effect of different trailing structure morphologies (e.g. oral arms and tentacles), swimming gaits, and kinematics on flow patterns were measured using PIV. Baseline swimming performance using biomimetic settings (but no trailing structures) was characterized by a cycle average velocity of 6.58 cm s-1, thrust of 1.9 N, and power input of 5.7 W, yielding a vehicle efficiency of 2.2% and a cost of transport of 15.4 J kg-1 m-1.

  12. Passive energy recapture in jellyfish contributes to propulsive advantage over other metazoans

    PubMed Central

    Gemmell, Brad J.; Costello, John H.; Colin, Sean P.; Stewart, Colin J.; Dabiri, John O.; Tafti, Danesh; Priya, Shashank

    2013-01-01

    Gelatinous zooplankton populations are well known for their ability to take over perturbed ecosystems. The ability of these animals to outcompete and functionally replace fish that exhibit an effective visual predatory mode is counterintuitive because jellyfish are described as inefficient swimmers that must rely on direct contact with prey to feed. We show that jellyfish exhibit a unique mechanism of passive energy recapture, which is exploited to allow them to travel 30% further each swimming cycle, thereby reducing metabolic energy demand by swimming muscles. By accounting for large interspecific differences in net metabolic rates, we demonstrate, contrary to prevailing views, that the jellyfish (Aurelia aurita) is one of the most energetically efficient propulsors on the planet, exhibiting a cost of transport (joules per kilogram per meter) lower than other metazoans. We estimate that reduced metabolic demand by passive energy recapture improves the cost of transport by 48%, allowing jellyfish to achieve the large sizes required for sufficient prey encounters. Pressure calculations, using both computational fluid dynamics and a newly developed method from empirical velocity field measurements, demonstrate that this extra thrust results from positive pressure created by a vortex ring underneath the bell during the refilling phase of swimming. These results demonstrate a physical basis for the ecological success of medusan swimmers despite their simple body plan. Results from this study also have implications for bioinspired design, where low-energy propulsion is required. PMID:24101461

  13. A Survey of Jellyfish Sting Knowledge among Naval Personnel in Northeast China

    PubMed Central

    Kan, Ting; Gui, Li; Shi, Wenwen; Huang, Yan; Li, Shuang; Qiu, Chen

    2016-01-01

    Background: Jellyfish envenomation is common along the coastal area, and can cause severe consequences. Naval personnel are among the high-risk population for this injury. The aim of this study was to assess knowledge regarding jellyfish envenomation among naval personnel in a navy unit in northeast China. Methods: A predesigned questionnaire was distributed to 120 naval members in January 2015. The data of 108 respondents were included in the statistical analysis. Results: We found that 38.0% of the respondents selected jellyfish sting as the common wound in their units, and 13.0% had experienced or observed this injury. In addition, 63.0% of the participants rated their own knowledge as “low” or “none”. The average score they got was 5.77 ± 2.50, with only 16.7% getting a score above 60% of the full score. The correct rates of five questions were below 60%. No statistical differences existed in the knowledge score among different groups of respondents defined by socio-demographic variables. Conclusions: Jellyfish sting is common in this navy unit, but personnel got a low score on the knowledge assessment. They also lacked confidence in first aid. Medical education and training should be implemented to address this issue. PMID:27447652

  14. Passive energy recapture in jellyfish contributes to propulsive advantage over other metazoans.

    PubMed

    Gemmell, Brad J; Costello, John H; Colin, Sean P; Stewart, Colin J; Dabiri, John O; Tafti, Danesh; Priya, Shashank

    2013-10-29

    Gelatinous zooplankton populations are well known for their ability to take over perturbed ecosystems. The ability of these animals to outcompete and functionally replace fish that exhibit an effective visual predatory mode is counterintuitive because jellyfish are described as inefficient swimmers that must rely on direct contact with prey to feed. We show that jellyfish exhibit a unique mechanism of passive energy recapture, which is exploited to allow them to travel 30% further each swimming cycle, thereby reducing metabolic energy demand by swimming muscles. By accounting for large interspecific differences in net metabolic rates, we demonstrate, contrary to prevailing views, that the jellyfish (Aurelia aurita) is one of the most energetically efficient propulsors on the planet, exhibiting a cost of transport (joules per kilogram per meter) lower than other metazoans. We estimate that reduced metabolic demand by passive energy recapture improves the cost of transport by 48%, allowing jellyfish to achieve the large sizes required for sufficient prey encounters. Pressure calculations, using both computational fluid dynamics and a newly developed method from empirical velocity field measurements, demonstrate that this extra thrust results from positive pressure created by a vortex ring underneath the bell during the refilling phase of swimming. These results demonstrate a physical basis for the ecological success of medusan swimmers despite their simple body plan. Results from this study also have implications for bioinspired design, where low-energy propulsion is required.

  15. Detection of microvasculature alterations by synchrotron radiation in murine with delayed jellyfish envenomation syndrome.

    PubMed

    Wang, Beilei; Zhang, Bo; Huo, Hua; Wang, Tao; Wang, Qianqian; Wu, Yuanlin; Xiao, Liang; Ren, Yuqi; Zhang, Liming

    2014-04-01

    Using the tentacle extract (TE) from the jellyfish Cyanea capillata, we have previously established a delayed jellyfish envenomation syndrome (DJES) model, which is meaningful for clinical interventions against jellyfish stings. However, the mechanism of DJES still remains unclear. Thus, this study aimed to explore its potential mechanism by detecting TE-induced microvasculature alterations in vivo and ex vivo. Using a third-generation synchrotron radiation facility, we, for the first time, directly observed the blood vessel alterations induced by jellyfish venom in vivo and ex vivo. Firstly, microvasculature imaging of whole-body mouse in vivo indicated that the small blood vessel branches in the liver and kidney in the TE-treated group, seemed much thinner than those in the control group. Secondly, 3D imaging of kidney ex vivo showed that the kidneys in the TE-treated group had incomplete vascular trees where distal vessel branches were partly missing and disorderly disturbed. Finally, histopathological analysis found that obvious morphological changes, especially hemorrhagic effects, were also present in the TE-treated kidney. Thus, TE-induced microvasculature changes might be one of the important mechanisms of multiple organ dysfunctions in DJES. In addition, the methods we employed here will probably facilitate further studies on developing effective intervention strategies against DJES.

  16. Vertical distribution of giant jellyfish, Nemopilema nomurai using acoustics and optics

    NASA Astrophysics Data System (ADS)

    Kim, Seonghun; Lee, Kyounghoon; Yoon, Won Duk; Lee, Hyungbeen; Hwang, Kangseok

    2016-03-01

    Nemopilema nomurai jellyfish, which are believed to complete their development in the East China Sea, have started migrating into the Yellow Sea in recent years. We obtained biomass estimates of this species in the Yellow Sea using bottom trawl fishing gear and sighting surveys over a 5-year period. These methods are effective for obtaining N. nomurai jellyfish density estimates and information about the community distribution near the bottom or surface of the sea. To verify the vertical distributions of giant jellyfish between, we used hydroacoustic equipment, including an optical stereo camera system attached to a towed sledge and an echo counting method with scientific echosounder system. Acoustic and optical data were collected while the vessel moved at 3 knots, from which the distribution and density of N. nomurai jellyfish were analyzed. Subsequently, the camera system was towed from a 7 m mean depth to sea level, with the detection range of the acoustic system extending from an 8 m depth to the bottom surface. The optical and acoustic methods indicated the presence of vertical distribution of 0.113 (inds/m3) and 0.064 (inds/m3), respectively. However, the vertical distribution indicated that around 93% of individuals occurred at a depth range of 10-40 m; thus, a 2.4-fold greater density was estimated by acoustic echo counting compared to the optical method.

  17. Learning from jellyfish: Fluid transport in muscular pumps at intermediate Reynolds numbers

    NASA Astrophysics Data System (ADS)

    Nawroth, Janna; Dabiri, John

    2010-11-01

    Biologically inspired hydrodynamic propulsion and maneuvering strategies promise the advancement of medical implants and minimally invasive clinical tools. We have chosen juvenile jellyfish as a model system for investigating fluid dynamics and morphological properties underlying fluid transport by a muscular pump at intermediate Reynolds numbers. Recently we have described how natural variations in viscous forces are balanced by changes in jellyfish body shape (phenotypic plasticity), to the effect of facilitating efficient body-fluid interaction. Complementing these studies in our live model organisms, we are also engaged in engineering an artificial jellyfish, that is, a jellyfish-inspired construct of a flexible plastic sheet actuated by a monolayer of rat cardiomyocytes. The main challenges here are (1) to derive a body shape and deformation suitable for effective fluid transport under physiological conditions, (2) to understand the mechanical properties of the muscular film and derive a design capable of the desired deformation, (3) to master the proper alignment and timely contraction of the muscle component needed to achieve the desired deformation, and (4) to evaluate the performance of the design.

  18. Neutralization of toxic effects of different crude jellyfish venoms by an extract of Ipomoea pes-caprae (L.) R. Br.

    PubMed

    Pongprayoon, U; Bohlin, L; Wasuwat, S

    1991-10-01

    An extract (IPA) of the plant Ipomoea pes-caprae (L.) R. Br., previously shown to be clinically effective toward dermatitis caused by venomous jellyfishes, was studied as to its ability to neutralize toxic activities of jellyfish venoms. Different venoms exhibited different degrees of activity. When IPA was incubated with active venoms, it inhibited the actions of all jellyfish venoms tested, with IC50 values in the range of 0.3-0.8 mgIPA/mg venom for proteolytic action, and with about 10 times lower IC50 values for the neutralization of haemolytic action. These activities of IPA support the previously reported effectiveness in the treatment of dermatitis caused by jellyfish sting.

  19. Investigation of a steam generator tube rupture sequence using VICTORIA

    SciTech Connect

    Bixler, N.E.; Erickson, C.M.; Schaperow, J.H.

    1995-12-31

    VICTORIA-92 is a mechanistic computer code for analyzing fission product behavior within the reactor coolant system (RCS) during a severe reactor accident. It provides detailed predictions of the release of radionuclides and nonradioactive materials from the core and transport of these materials within the RCS. The modeling accounts for the chemical and aerosol processes that affect radionuclide behavior. Coupling of detailed chemistry and aerosol packages is a unique feature of VICTORIA; it allows exploration of phenomena involving deposition, revaporization, and re-entrainment that cannot be resolved with other codes. The purpose of this work is to determine the attenuation of fission products in the RCS and on the secondary side of the steam generator in an accident initiated by a steam generator tube rupture (SGTR). As a class, bypass sequences have been identified in NUREG-1150 as being risk dominant for the Surry and Sequoyah pressurized water reactor (PWR) plants.

  20. Regional climate model performance in the Lake Victoria basin

    NASA Astrophysics Data System (ADS)

    Williams, Karina; Chamberlain, Jill; Buontempo, Carlo; Bain, Caroline

    2015-03-01

    Lake Victoria, the second largest freshwater lake in the world, plays a crucial role in the hydrology of equatorial eastern Africa. Understanding how climate change may alter rainfall and evaporation patterns is thus of vital importance for the economic development and the livelihood of the region. Regional rainfall distribution appears, up to a large extent, to be controlled by local drivers which may be not well resolved in general circulation model simulations. We investigate the performance over the Lake Victoria basin of an ensemble of UK Met Office Hadley Centre regional climate model (HadRM3P) simulations at 50 km, driven by five members of the Hadley Centre global perturbed-physics ensemble (QUMP). This is part of the validation of an ensemble of simulations that has been used to assess the impacts of climate change over the continent over the period 1950-2099. We find that the regional climate model is able to simulate a lake/land breeze over Lake Victoria, which is a significant improvement over the driving global climate model and a vital step towards reproducing precipitation characteristics in the region. The local precipitation correlates well with large-scale processes in the Pacific Ocean and Indian Ocean, which is in agreement with observations. We find that the spatial pattern of precipitation in the region and the diurnal cycle of convection is well represented although the amount of rainfall over the lake appears to be overestimated in most seasons. Reducing the observational uncertainty in precipitation over the lake through future field campaigns would enable this model bias to be better quantified. We conclude that increasing the spatial resolution of the model significantly improves its ability to simulate the current climate of the Lake Victoria basin. We suggest that, despite the higher computational costs, the inclusion of a model which allows two-way interactions between the lake and its surroundings should be seriously considered for

  1. View of 'Bottomless Bay' on Rim of 'Victoria'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    As part of its investigation of 'Victoria Crater,' NASA's Mars Exploration Rover Opportunity examined a section of the scalloped rim called 'Bottomless Bay' (or 'Bahia sin Fondo'). This view shows the northeastern side of Bottomless Bay as seen from the southwest. The exposures combined into this mosaic were taken by the rover's panoramic camera through a 750-nanometer filter during the 1,019th Martian day, or sol, of Opportunity's Mars-surface mission (Dec. 5, 2006).

  2. Efficacy of Venom from Tentacle of Jellyfish Stomolophus meleagris (Nemopilema nomurai) against the Cotton Bollworm Helicoverpa armigera

    PubMed Central

    Yu, Huahua; Li, Rongfeng; Dong, Xiangli; Xing, Ronge; Liu, Song; Li, Pengcheng

    2014-01-01

    Efficacy of venom from tentacle of jellyfish Stomolophus meleagris against the cotton bollworm Helicoverpa armigera was determined. Venom from tentacle of jellyfish Stomolophus meleagris could inhibit the growth of Helicoverpa armigera and the weight inhibiting rate of sample NFr-2 was 60.53%. Of the six samples, only NFr-2 had high insecticidal activity against Helicoverpa armigera and the corrected mortality recorded at 7 d was 74.23%. PMID:25162008

  3. Spatiotemporal distribution of protozooplankton and copepod nauplii in relation to the occurrence of giant jellyfish in the Yellow Sea

    NASA Astrophysics Data System (ADS)

    Wang, Lu; Xu, Kuidong

    2013-11-01

    The occurrence of the giant jellyfish, Nemopilema nomurai, has been a frequent phenomenon in the Yellow Sea. However, the relationship between the giant jellyfish and protozoa, in particular ciliates, remains largely unknown. We investigated the distribution of nanoflagellates, ciliates, Noctiluca scintillans, and copepod nauplii along the transect 33°N in the Yellow Sea in June and August, 2012, during an occurrence of the giant jellyfish, and in October of that year when the jellyfish was absent. The organisms studied were mainly concentrated in the surface waters in summer, while in autumn they were evenly distributed in the water column. Nanoflagellate, ciliate, and copepod nauplii biomasses increased from early June to August along with jellyfish growth, the first two decreased in October, while N. scintillans biomass peaked in early June to 3 571 μg C/L and decreased in August and October. In summer, ciliate biomass greatly exceeded that of copepod nauplii (4.61-15.04 μg C/L vs. 0.34-0.89 μg C/L). Ciliate production was even more important than biomass, ranging from 6.59 to 34.19 μg C/(L·d) in summer. Our data suggest a tight and positive association among the nano-, micro-, and meso-zooplankton in the study area. Statistical analysis revealed that the abundance and total production of ciliate as well as loricate ciliate biomass were positively correlated with giant jellyfish biomass, indicating a possible predator-prey relationship between ciliates and giant jellyfish. This is in contrast to a previous study, which reported a significant reduction in ciliate standing crops due to the mass occurrence of N. nomurai in summer. Our study indicates that, with its high biomass and, in particular, high production ciliates might support the mass occurrence of giant jellyfish.

  4. Transcriptome pyrosequencing of the Antarctic brittle star Ophionotus victoriae.

    PubMed

    Burns, Gavin; Thorndyke, Michael C; Peck, Lloyd S; Clark, Melody S

    2013-03-01

    Brittle stars are included within a whole range of species, which contribute to knowledge in the medically important area of tissue regeneration. All brittle stars regenerate lose limbs, but the rate at which this occurs is highly variable and species-specific. One of the slowest rates of arm regeneration reported so far is that of the Antarctic Ophionotus victoriae. Additionally, O. victoriae also has an unusual delay in the onset of regeneration of about 5months. Both processes are of interest for the areas of regeneration biology and adaptation to cold environments. One method of understanding the details of regeneration events in brittle stars is to characterise the genes involved. In the largest transcriptome study of any ophiuroid to date, we describe the results of mRNA pyrosequencing from pooled samples of regenerating arms of O. victoriae. The sequencing reads resulted in 18,000 assembled contiguous sequences of which 19% were putatively annotated by blast sequence similarity searching. We focus on the identification of major gene families and pathways with potential relevance to the regenerative processes including the Wnt/β-catenin pathway, Hox genes, the SOX gene family and the TGF beta signalling pathways. These data significantly increase the amount of ophiuroid sequences publicly available and provide candidate transcripts for the further investigation of the unusual regenerative process in this Antarctic ophiuroid.

  5. Seasonal changes in infection with trematode species utilizing jellyfish as hosts: evidence of transmission to definitive host fish via medusivory

    PubMed Central

    Kondo, Yusuke; Ohtsuka, Susumu; Hirabayashi, Takeshi; Okada, Shoma; Ogawa, Nanako O.; Ohkouchi, Naohiko; Shimazu, Takeshi; Nishikawa, Jun

    2016-01-01

    In the Seto Inland Sea of western Japan, metacercariae of three species of trematodes, Lepotrema clavatum Ozaki, 1932, Cephalolepidapedon saba Yamaguti, 1970, and Opechona olssoni (Yamaguti, 1934), were found in the mesoglea of the jellyfish Aurelia aurita s.l., Chrysaora pacifica, and Cyanea nozakii. Moreover, these jellyfish frequently harbored juveniles of the fish species Psenopsis anomala, Thamnaconus modestus, and Trachurus japonicus. The former two fish species are well-known medusivores. We investigated seasonal changes in the prevalence and intensity of these metacercariae in their host jellyfish from March 2010 to September 2012 and presumed that infection by the trematodes of the definitive host fish occurs through these associations. The mean intensity of metacercariae in A. aurita s.l. clearly showed seasonality, being consistently high in June of each year. The intensity of metacercariae in C. nozakii was highest among all jellyfish hosts and appeared to be enhanced by medusivory of this second intermediate, and/or paratenic host. Trophic interactions between jellyfish and associated fish were verified using both gut content and stable isotope analyses. The detection of trematodes and nematocysts in the guts of P. anomala and T. modestus juveniles, in addition to stable isotope analysis, suggests that transmission of the parasites occurs via prey-predator relationships. In addition, the stable isotope analysis also suggested that P. anomala is more nutritionally dependent on jellyfish than Th. modestus and Tr. japonicus. PMID:27055563

  6. Seasonal changes in infection with trematode species utilizing jellyfish as hosts: evidence of transmission to definitive host fish via medusivory.

    PubMed

    Kondo, Yusuke; Ohtsuka, Susumu; Hirabayashi, Takeshi; Okada, Shoma; Ogawa, Nanako O; Ohkouchi, Naohiko; Shimazu, Takeshi; Nishikawa, Jun

    2016-01-01

    In the Seto Inland Sea of western Japan, metacercariae of three species of trematodes, Lepotrema clavatum Ozaki, 1932, Cephalolepidapedon saba Yamaguti, 1970, and Opechona olssoni (Yamaguti, 1934), were found in the mesoglea of the jellyfish Aurelia aurita s.l., Chrysaora pacifica, and Cyanea nozakii. Moreover, these jellyfish frequently harbored juveniles of the fish species Psenopsis anomala, Thamnaconus modestus, and Trachurus japonicus. The former two fish species are well-known medusivores. We investigated seasonal changes in the prevalence and intensity of these metacercariae in their host jellyfish from March 2010 to September 2012 and presumed that infection by the trematodes of the definitive host fish occurs through these associations. The mean intensity of metacercariae in A. aurita s.l. clearly showed seasonality, being consistently high in June of each year. The intensity of metacercariae in C. nozakii was highest among all jellyfish hosts and appeared to be enhanced by medusivory of this second intermediate, and/or paratenic host. Trophic interactions between jellyfish and associated fish were verified using both gut content and stable isotope analyses. The detection of trematodes and nematocysts in the guts of P. anomala and T. modestus juveniles, in addition to stable isotope analysis, suggests that transmission of the parasites occurs via prey-predator relationships. In addition, the stable isotope analysis also suggested that P. anomala is more nutritionally dependent on jellyfish than Th. modestus and Tr. japonicus.

  7. Recent MELCOR and VICTORIA Fission Product Research at the NRC

    SciTech Connect

    Bixler, N.E.; Cole, R.K.; Gauntt, R.O.; Schaperow, J.H.; Young, M.F.

    1999-01-21

    The MELCOR and VICTORIA severe accident analysis codes, which were developed at Sandia National Laboratories for the U. S. Nuclear Regulatory Commission, are designed to estimate fission product releases during nuclear reactor accidents in light water reactors. MELCOR is an integrated plant-assessment code that models the key phenomena in adequate detail for risk-assessment purposes. VICTORIA is a more specialized fission- product code that provides detailed modeling of chemical reactions and aerosol processes under the high-temperature conditions encountered in the reactor coolant system during a severe reactor accident. This paper focuses on recent enhancements and assessments of the two codes in the area of fission product chemistry modeling. Recently, a model for iodine chemistry in aqueous pools in the containment building was incorporated into the MELCOR code. The model calculates dissolution of iodine into the pool and releases of organic and inorganic iodine vapors from the pool into the containment atmosphere. The main purpose of this model is to evaluate the effect of long-term revolatilization of dissolved iodine. Inputs to the model include dose rate in the pool, the amount of chloride-containing polymer, such as Hypalon, and the amount of buffering agents in the containment. Model predictions are compared against the Radioiodine Test Facility (RTF) experiments conduced by Atomic Energy of Canada Limited (AECL), specifically International Standard Problem 41. Improvements to VICTORIA's chemical reactions models were implemented as a result of recommendations from a peer review of VICTORIA that was completed last year. Specifically, an option is now included to model aerosols and deposited fission products as three condensed phases in addition to the original option of a single condensed phase. The three-condensed-phase model results in somewhat higher predicted fission product volatilities than does the single-condensed-phase model. Modeling of U02

  8. Jellyfish prediction of occurrence from remote sensing data and a non-linear pattern recognition approach

    NASA Astrophysics Data System (ADS)

    Albajes-Eizagirre, Anton; Romero, Laia; Soria-Frisch, Aureli; Vanhellemont, Quinten

    2011-11-01

    Impact of jellyfish in human activities has been increasingly reported worldwide in recent years. Segments such as tourism, water sports and leisure, fisheries and aquaculture are commonly damaged when facing blooms of gelatinous zooplankton. Hence the prediction of the appearance and disappearance of jellyfish in our coasts, which is not fully understood from its biological point of view, has been approached as a pattern recognition problem in the paper presented herein, where a set of potential ecological cues was selected to test their usefulness for prediction. Remote sensing data was used to describe environmental conditions that could support the occurrence of jellyfish blooms with the aim of capturing physical-biological interactions: forcing, coastal morphology, food availability, and water mass characteristics are some of the variables that seem to exert an effect on jellyfish accumulation on the shoreline, under specific spatial and temporal windows. A data-driven model based on computational intelligence techniques has been designed and implemented to predict jellyfish events on the beach area as a function of environmental conditions. Data from 2009 over the NW Mediterranean continental shelf have been used to train and test this prediction protocol. Standard level 2 products are used from MODIS (NASA OceanColor) and MERIS (ESA - FRS data). The procedure for designing the analysis system can be described as following. The aforementioned satellite data has been used as feature set for the performance evaluation. Ground truth has been extracted from visual observations by human agents on different beach sites along the Catalan area. After collecting the evaluation data set, the performance between different computational intelligence approaches have been compared. The outperforming one in terms of its generalization capability has been selected for prediction recall. Different tests have been conducted in order to assess the prediction capability of the

  9. Reynolds number limits for jet propulsion: a numerical study of simplified jellyfish.

    PubMed

    Herschlag, Gregory; Miller, Laura

    2011-09-21

    The Scallop theorem states that reciprocal methods of locomotion, such as jet propulsion or paddling, will not work in Stokes flow (Reynolds number=0). In nature the effective limit of jet propulsion is still in the range where inertial forces are significant. It appears that almost all animals that use jet propulsion swim at Reynolds numbers (Re) of about 5 or more. Juvenile squid and octopods hatch from the egg already swimming in this inertial regime. Juvenile jellyfish, or ephyrae, break off from polyps swimming at Re greater than 5. Many other organisms, such as scallops, rarely swim at Re less than 100. The limitations of jet propulsion at intermediate Re is explored here using the immersed boundary method to solve the 2D Navier-Stokes equations coupled to the motion of a simplified jellyfish. The contraction and expansion kinematics are prescribed, but the forward and backward swimming motions of the idealized jellyfish are emergent properties determined by the resulting fluid dynamics. Simulations are performed for both an oblate bell shape using a paddling mode of swimming and a prolate bell shape using jet propulsion. Average forward velocities and work put into the system are calculated for Re between 1 and 320. The results show that forward velocities rapidly decay with decreasing Re for all bell shapes when Re<10. Similarly, the work required to generate the pulsing motion increases significantly for Re<10. When compared to actual organisms, the swimming velocities and vortex separation patterns for the model prolate agree with those observed in Nemopsis bachei. The forward swimming velocities of the model oblate jellyfish after two pulse cycles are comparable to those reported for Aurelia aurita, but discrepancies are observed in the vortex dynamics between when the 2D model oblate jellyfish and the organism. This discrepancy is likely due to a combination of the differences between the 3D reality of the jellyfish and the 2D simplification, as well as

  10. A novel protein toxin from the deadly box jellyfish (Sea Wasp, Habu-kurage) Chiropsalmus quadrigatus.

    PubMed

    Nagai, Hiroshi; Takuwa-Kuroda, Kyoko; Nakao, Masahiro; Oshiro, Naomasa; Iwanaga, Setsuko; Nakajima, Terumi

    2002-01-01

    The deadly box jellyfish (Sea Wasp, Habu-kurage in Japanese) Chiropsalmus quadrigatus Haeckel (Cubozoa) is distributed widely in the tropical Pacific region. In Japan, three fatal cases due to stings from this species have been reported officially. We successfully isolated C. quadrigatus toxin-A (CqTX-A, 44 kDa), a major proteinaceous toxin, for the first time, from the nematocysts of C. quadrigatus. CqTX-A showed lethal toxicity to crayfish when administered via intraperitoneal injection (LD50 = 80 microg/kg) and hemolytic activity toward 0.8% sheep red blood cells (ED50 = 160 ng/ml). Furthermore, we sequenced the cDNA encoding CqTX-A. The deduced amino acid sequence of CqTX-A (462 amino acids) showed 25.2% and 21.6% sequence similarity to Carybdea rastoni toxins (CrTXs) and Carybdea alata toxin-A (CrTX-A), respectively, which are Cubozoan jellyfish toxins.

  11. Comparative analysis of methods for concentrating venom from jellyfish Rhopilema esculentum Kishinouye

    NASA Astrophysics Data System (ADS)

    Li, Cuiping; Yu, Huahua; Feng, Jinhua; Chen, Xiaolin; Li, Pengcheng

    2009-02-01

    In this study, several methods were compared for the efficiency to concentrate venom from the tentacles of jellyfish Rhopilema esculentum Kishinouye. The results show that the methods using either freezing-dry or gel absorption to remove water to concentrate venom are not applicable due to the low concentration of the compounds dissolved. Although the recovery efficiency and the total venom obtained using the dialysis dehydration method are high, some proteins can be lost during the concentrating process. Comparing to the lyophilization method, ultrafiltration is a simple way to concentrate the compounds at high percentage but the hemolytic activities of the proteins obtained by ultrafiltration appear to be lower. Our results suggest that overall lyophilization is the best and recommended method to concentrate venom from the tentacles of jellyfish. It shows not only the high recovery efficiency for the venoms but high hemolytic activities as well.

  12. Jellyfish aggregations and leatherback turtle foraging patterns in a temperate coastal environment.

    PubMed

    Houghton, Jonathan D R; Doyle, Thomas K; Wilson, Mark W; Davenport, John; Hays, Graeme C

    2006-08-01

    Leatherback turtles (Dermochelys coriacea) are obligate predators of gelatinous zooplankton. However, the spatial relationship between predator and prey remains poorly understood beyond sporadic and localized reports. To examine how jellyfish (Phylum Cnidaria: Orders Semaeostomeae and Rhizostomeae) might drive the broad-scale distribution of this wide ranging species, we employed aerial surveys to map jellyfish throughout a temperate coastal shelf area bordering the northeast Atlantic. Previously unknown, consistent aggregations of Rhizostoma octopus extending over tens of square kilometers were identified in distinct coastal "hotspots" during consecutive years (2003-2005). Examination of retrospective sightings data (>50 yr) suggested that 22.5% of leatherback distribution could be explained by these hotspots, with the inference that these coastal features may be sufficiently consistent in space and time to drive long-term foraging associations.

  13. Symmetrization in jellyfish: reorganization to regain function, and not lost parts.

    PubMed

    Abrams, Michael J; Goentoro, Lea

    2016-02-01

    We recently reported a previously unidentified strategy of self-repair in the moon jellyfish Aurelia aurita. Rather than regenerating lost parts, juvenile Aurelia reorganize remaining parts to regain essential body symmetry. This process that we called symmetrization is rapid and frequent, and is not driven by cell proliferation or cell death. Instead, the swimming machinery generates mechanical forces that drive symmetrization. We found evidence for symmetrization across three other species of jellyfish (Chrysaora pacifica, Mastigias sp., and Cotylorhiza tuberculata). We propose reorganization to regain function without recovery of initial morphology as a potentially broad class of self-repair strategy beyond radially symmetrical animals, and discuss the implications of this finding on the evolution of self-repair strategies in animals.

  14. Pentaplex PCR as screening assay for jellyfish species identification in food products.

    PubMed

    Armani, Andrea; Giusti, Alice; Castigliego, Lorenzo; Rossi, Aurelio; Tinacci, Lara; Gianfaldoni, Daniela; Guidi, Alessandra

    2014-12-17

    Salted jellyfish, a traditional food in Asian Countries, is nowadays spreading on the Western markets. In this work, we developed a Pentaplex PCR for the identification of five edible species (Nemopilema nomurai, Rhopilema esculentum, Rhizostoma pulmo, Pelagia noctiluca, and Cotylorhiza tuberculata), which cannot be identified by a mere visual inspection in jellyfish products sold as food. A common degenerated forward primer and five specie-specific reverse primers were designed to amplify COI gene regions of different lengths. Another primer pair targeted the 28SrRNA gene and was intended as common positive reaction control. Considering the high level of degradation in the DNA extracted from acidified and salted products, the maximum length of the amplicons was set at 200 bp. The PCR was developed using 66 reference DNA samples. It gave successful amplifications in 85.4% of 48 ready to eat products (REs) and in 60% of 30 classical salted products (CPs) collected on the market.

  15. Protective effects of batimastat against hemorrhagic injuries in delayed jellyfish envenomation syndrome models.

    PubMed

    Wang, Beilei; Liu, Dan; Liu, Guoyan; Zhang, Xin; Wang, Qianqian; Zheng, Jiemin; Zhou, Yonghong; He, Qian; Zhang, Liming

    2015-12-15

    Previously, we established delayed jellyfish envenomation syndrome (DJES) models and proposed that the hemorrhagic toxins in jellyfish tentacle extracts (TE) play a significant role in the liver and kidney injuries of the experimental model. Further, we also demonstrated that metalloproteinases are the central toxic components of the jellyfish Cyanea capillata (C. capillata), which may be responsible for the hemorrhagic effects. Thus, metalloproteinase inhibitors appear to be a promising therapeutic alternative for the treatment of hemorrhagic injuries in DJES. In this study, we examined the metalloproteinase activity of TE from the jellyfish C. capillata using zymography analyses. Our results confirmed that TE possessed a metalloproteinase activity, which was also sensitive to heat. Then, we tested the effect of metalloproteinase inhibitor batimastat (BB-94) on TE-induced hemorrhagic injuries in DJES models. Firstly, using SR-based X-ray microangiography, we found that BB-94 significantly improved TE-induced hepatic and renal microvasculature alterations in DJES mouse model. Secondly, under synchrotron radiation micro-computed tomography (SR-μCT), we also confirmed that BB-94 reduced TE-induced hepatic and renal microvasculature changes in DJES rat model. In addition, being consistent with the imaging results, histopathological and terminal deoxynucleotidyl transferase-mediated UTP end labeling (TUNEL)-like staining observations also clearly corroborated this hypothesis, as BB-94 was highly effective in neutralizing TE-induced extensive hemorrhage and necrosis in DJES rat model. Although it may require further clinical studies in the near future, the current study opens up the possibilities for the use of the metalloproteinase inhibitor, BB-94, in the treatment of multiple organ hemorrhagic injuries in DJES.

  16. Drowning deaths between 1861 and 2000 in Victoria, Australia

    PubMed Central

    Ozanne-Smith, Joan

    2017-01-01

    Abstract Objective To identify the long-term patterns of drowning mortality in the state of Victoria, Australia, and to describe the historical context in which the decrease occurred. Methods We obtained data on drowning deaths and population statistics from the Australian Bureau of Statistics and its predecessors for the period 1861 to 2000. From these data, we calculated drowning death rates per 100 000 population per year, by gender and age. We reviewed primary and secondary historical resources, such as government and newspaper archives, books and the Internet, to identify changes or events in the state that may have affected drowning mortality. Findings From 1861 to 2000, at least 18 070 people drowned in Victoria. Male drowning rates were higher than those for females in all years and for all ages. Both sexes experienced the highest drowning rate in 1863 (79.5 male deaths per 100 000 population and 18.8 female death per 100 000 population). The lowest drowning rate was documented in 2000 (1.4 male deaths per 100 000 population and 0.3 female deaths per 100 000 population). The reduction patterns of drowning mortality occurred within a historical context of factors that directly affected drowning mortality, such as the improvement in people’s water safety skills, or those that incidentally affected drowning mortality, like infrastructure development. Conclusion We identified patterns of reduction in drowning mortality, both in males and females and across age groups. These patterns could be linked to events and factors that happened in Victoria during this period. These findings may have relevance to current developing communities. PMID:28250530

  17. Details of Layers in Victoria Crater's Cape St. Vincent

    NASA Technical Reports Server (NTRS)

    2007-01-01

    NASA's Mars Exploration Rover Opportunity rover spent about 300 sols (Martian days) during 2006 and 2007 traversing the rim of Victoria Crater. Besides looking for a good place to enter the crater, the rover obtained images of rock outcrops exposed at several cliffs along the way.

    The cliff in this image from Opportunity's panoramic camera (Pancam) is informally named Cape St. Vincent. It is a promontory approximately 12 meters (39 feet) tall on the northern rim of Victoria crater, near the farthest point along the rover's traverse around the rim. Layers seen in Cape St. Vincent have proven to be among the best examples of meter scale cross-bedding observed on Mars to date. Cross-bedding is a geologic term for rock layers which are inclined relative to the horizontal and which are indicative of ancient sand dune deposits. In order to get a better look at these outcrops, Pancam 'super-resolution' imaging techniques were utilized. Super-resolution is a type of imaging mode which acquires many pictures of the same target to reconstruct a digital image at a higher resolution than is native to the camera. These super-resolution images have allowed scientists to discern that the rocks at Victoria Crater once represented a large dune field, not unlike the Sahara desert on Earth, and that this dune field migrated with an ancient wind flowing from the north to the south across the region. Other rover chemical and mineral measurements have shown that many of the ancient sand dunes studied in Meridiani Planum were modified by surface and subsurface liquid water long ago.

    This is a Mars Exploration Rover Opportunity Panoramic Camera image acquired on sol 1167 (May 7, 2007), and was constructed from a mathematical combination of 16 different blue filter (480 nm) images.

  18. Exploration of Victoria crater by the Mars rover Opportunity.

    PubMed

    Squyres, S W; Knoll, A H; Arvidson, R E; Ashley, J W; Bell, J F; Calvin, W M; Christensen, P R; Clark, B C; Cohen, B A; de Souza, P A; Edgar, L; Farrand, W H; Fleischer, I; Gellert, R; Golombek, M P; Grant, J; Grotzinger, J; Hayes, A; Herkenhoff, K E; Johnson, J R; Jolliff, B; Klingelhöfer, G; Knudson, A; Li, R; McCoy, T J; McLennan, S M; Ming, D W; Mittlefehldt, D W; Morris, R V; Rice, J W; Schröder, C; Sullivan, R J; Yen, A; Yingst, R A

    2009-05-22

    The Mars rover Opportunity has explored Victoria crater, an approximately 750-meter eroded impact crater formed in sulfate-rich sedimentary rocks. Impact-related stratigraphy is preserved in the crater walls, and meteoritic debris is present near the crater rim. The size of hematite-rich concretions decreases up-section, documenting variation in the intensity of groundwater processes. Layering in the crater walls preserves evidence of ancient wind-blown dunes. Compositional variations with depth mimic those approximately 6 kilometers to the north and demonstrate that water-induced alteration at Meridiani Planum was regional in scope.

  19. Exploration of Victoria crater by the mars rover opportunity

    USGS Publications Warehouse

    Squyres, S. W.; Knoll, A.H.; Arvidson, R. E.; Ashley, James W.; Bell, J.F.; Calvin, W.M.; Christensen, P.R.; Clark, B. C.; Cohen, B. A.; De Souza, P.A.; Edgar, L.; Farrand, W. H.; Fleischer, I.; Gellert, Ralf; Golombek, M.P.; Grant, J.; Grotzinger, J.; Hayes, A.; Herkenhoff, K. E.; Johnson, J. R.; Jolliff, B.; Klingelhofer, G.; Knudson, A.; Li, R.; McCoy, T.J.; McLennan, S.M.; Ming, D. W.; Mittlefehldt, D. W.; Morris, R.V.; Rice, J. W.; Schroder, C.; Sullivan, R.J.; Yen, A.; Yingst, R.A.

    2009-01-01

    The Mars rover Opportunity has explored Victoria crater, a ???750-meter eroded impact crater formed in sulfate-rich sedimentary rocks. Impact-related stratigraphy is preserved in the crater walls, and meteoritic debris is present near the crater rim. The size of hematite-rich concretions decreases up-section, documenting variation in the intensity of groundwater processes. Layering in the crater walls preserves evidence of ancient wind-blown dunes. Compositional variations with depth mimic those ???6 kilometers to the north and demonstrate that water-induced alteration at Meridiani Planum was regional in scope.

  20. View of 'Bottomless Bay' on Rim of 'Victoria' (Altered Contrast)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    As part of its investigation of 'Victoria Crater,' NASA's Mars Exploration Rover Opportunity examined a section of the scalloped rim called 'Bottomless Bay' (or 'Bahia sin Fondo'). This view shows the northeastern side of Bottomless Bay as seen from the southwest. The exposures combined into this mosaic were taken by the rover's panoramic camera through a 750-nanometer filter during the 1,019th Martian day, or sol, of Opportunity's Mars-surface mission (Dec. 5, 2006). Contrast has been altered to improve the visibility of details in shadowed areas.

  1. Bigger Crater Farther South of 'Victoria' on Mars

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Annotated version

    The team operating NASA's Mars Exploration Rover Opportunity has chosen southeast as the direction for the rover's next extended journey, toward a crater more than 20 times wider than 'Victoria Crater.' Opportunity exited Victoria Crater on Aug. 28, 2008, after nearly a year investigating the interior.

    The crater to the southeast is about 22 kilometers (13.7 miles) in diameter and about 300 meters (1,000 feet) deep, exposing a much thicker stack of rock layers than those examined in Victoria Crater.

    The rover team informally calls the bigger crater 'Endeavour' and emphasizes that Opportunity may well never reach it. The rover has already operated more than 18 times longer than originally planned, and the distance to the big crater, about 12 kilometers (7 miles) matches the total distance Opportunity has driven since landing in early 2004. Driving southeastward is expected to take Opportunity to exposures of younger rock layers than is has previously seen and to provide access to rocks on the plain that were thrown long distances by impacts that excavated even deeper, more distant craters.

    The crater that Opportunity will drive toward dominates this orbital view from the Thermal Emission Imaging System (THEMIS) camera on NASA's Mars Odyssey orbiter. The much smaller Victoria Crater is the most prominent circle near the upper left corner of the image. This view is a mosaic of about 50 separate visible-light images taken by THEMIS.

    NASA's Jet Propulsion Laboratory manages the Mars Odyssey and Mars Exploration Rover missions for the NASA Science Mission Directorate, Washington, D.C. THEMIS was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the

  2. Reforming Victoria's primary health and community service sector: rural implications.

    PubMed

    Alford, K

    2000-01-01

    In 1999 the Victorian primary care and community support system began a process of substantial reform, involving purchasing reforms and a contested selection process between providers in large catchment areas across the State. The Liberal Government's electoral defeat in September 1999 led to a review of these reforms. This paper questions the reforms from a rural perspective. They were based on a generic template that did not consider rural-urban differences in health needs or other differences including socio-economic status, and may have reinforced if not aggravated rural-urban differences in the quality of and access to primary health care in Victoria.

  3. A biomimetic robotic jellyfish (Robojelly) actuated by shape memory alloy composite actuators.

    PubMed

    Villanueva, Alex; Smith, Colin; Priya, Shashank

    2011-09-01

    An analysis is conducted on the design, fabrication and performance of an underwater vehicle mimicking the propulsion mechanism and physical appearance of a medusa (jellyfish). The robotic jellyfish called Robojelly mimics the morphology and kinematics of the Aurelia aurita species. Robojelly actuates using bio-inspired shape memory alloy composite actuators. A systematic fabrication technique was developed to replicate the essential structural features of A. aurita. Robojelly's body was fabricated from RTV silicone having a total mass of 242 g and bell diameter of 164 mm. Robojelly was able to generate enough thrust in static water conditions to propel itself and achieve a proficiency of 0.19 s(-1) while the A. aurita achieves a proficiency of around 0.25 s(-1). A thrust analysis based on empirical measurements for a natural jellyfish was used to compare the performance of the different robotic configurations. The configuration with best performance was a Robojelly with segmented bell and a passive flap structure. Robojelly was found to consume an average power on the order of 17 W with the actuators not having fully reached a thermal steady state.

  4. Jellyfish mucin may have potential disease-modifying effects on osteoarthritis

    PubMed Central

    2009-01-01

    Background We aimed to study the effects of intra-articular injection of jellyfish mucin (qniumucin) on articular cartilage degeneration in a model of osteoarthritis (OA) created in rabbit knees by resection of the anterior cruciate ligament. Qniumucin was extracted from Aurelia aurita (moon jellyfish) and Stomolophus nomurai (Nomura's jellyfish) and purified by ion exchange chromatography. The OA model used 36 knees in 18 Japanese white rabbits. Purified qniumucin extracts from S. nomurai or A. aurita were used at 1 mg/ml. Rabbits were divided into four groups: a control (C) group injected with saline; a hyaluronic acid (HA)-only group (H group); two qniumucin-only groups (M groups); and two qniumucin + HA groups (MH groups). One milligram of each solution was injected intra-articularly once a week for 5 consecutive weeks, starting from 4 weeks after surgery. Ten weeks after surgery, the articular cartilage was evaluated macroscopically and histologically. Results In the C and M groups, macroscopic cartilage defects extended to the subchondral bone medially and laterally. When the H and both MH groups were compared, only minor cartilage degeneration was observed in groups treated with qniumucin in contrast to the group without qniumucin. Histologically, densely safranin-O-stained cartilage layers were observed in the H and two MH groups, but cartilage was strongly maintained in both MH groups. Conclusion At the concentrations of qniumucin used in this study, injection together with HA inhibited articular cartilage degeneration in this model of OA. PMID:19995451

  5. Feeding currents of the upside down jellyfish in the presence of background flow.

    PubMed

    Hamlet, Christina L; Miller, Laura A

    2012-11-01

    The upside-down jellyfish (Cassiopea spp.) is an ideal organism for examining feeding and exchange currents generated by bell pulsations due to its relatively sessile nature. Previous experiments and numerical simulations have shown that the oral arms play an important role in directing new fluid into the bell from along the substrate. All of this work, however, has considered the jellyfish in the absence of background flow, but the natural environments of Cassiopea and other cnidarians are dynamic. Flow velocities and directions fluctuate on multiple time scales, and mechanisms of particle capture may be fundamentally different in moving fluids. In this paper, the immersed boundary method is used to simulate a simplified jellyfish in flow. The elaborate oral arm structure is modeled as a homogenous porous layer. The results show that the oral arms trap vortices as they form during contraction and expansion of the bell. For constant flow conditions, the vortices are directed gently across the oral arms where particle capture occurs. For variable direction flows, the secondary structures change the overall pattern of the flow around the bell and appear to stabilize regions of mixing around the secondary mouths.

  6. To Pee, or Not to Pee: A Review on Envenomation and Treatment in European Jellyfish Species.

    PubMed

    Montgomery, Louise; Seys, Jan; Mees, Jan

    2016-07-08

    There is a growing cause for concern on envenoming European species because of jellyfish blooms, climate change and globalization displacing species. Treatment of envenomation involves the prevention of further nematocyst release and relieving local and systemic symptoms. Many anecdotal treatments are available but species-specific first aid response is essential for effective treatment. However, species identification is difficult in most cases. There is evidence that oral analgesics, seawater, baking soda slurry and 42-45 °C hot water are effective against nematocyst inhibition and giving pain relief. The application of topical vinegar for 30 s is effective on stings of specific species. Treatments, which produce osmotic or pressure changes can exacerbate the initial sting and aggravate symptoms, common among many anecdotal treatments. Most available therapies are based on weak evidence and thus it is strongly recommended that randomized clinical trials are undertaken. We recommend a vital increase in directed research on the effect of environmental factors on envenoming mechanisms and to establish a species-specific treatment. Adequate signage on jellyfish stings and standardized first aid protocols with emphasis on protective equipment and avoidance of jellyfish to minimize cases should be implemented in areas at risk.

  7. To Pee, or Not to Pee: A Review on Envenomation and Treatment in European Jellyfish Species

    PubMed Central

    Montgomery, Louise; Seys, Jan; Mees, Jan

    2016-01-01

    There is a growing cause for concern on envenoming European species because of jellyfish blooms, climate change and globalization displacing species. Treatment of envenomation involves the prevention of further nematocyst release and relieving local and systemic symptoms. Many anecdotal treatments are available but species-specific first aid response is essential for effective treatment. However, species identification is difficult in most cases. There is evidence that oral analgesics, seawater, baking soda slurry and 42–45 °C hot water are effective against nematocyst inhibition and giving pain relief. The application of topical vinegar for 30 s is effective on stings of specific species. Treatments, which produce osmotic or pressure changes can exacerbate the initial sting and aggravate symptoms, common among many anecdotal treatments. Most available therapies are based on weak evidence and thus it is strongly recommended that randomized clinical trials are undertaken. We recommend a vital increase in directed research on the effect of environmental factors on envenoming mechanisms and to establish a species-specific treatment. Adequate signage on jellyfish stings and standardized first aid protocols with emphasis on protective equipment and avoidance of jellyfish to minimize cases should be implemented in areas at risk. PMID:27399728

  8. The Jellyfish: smart electro-active polymers for an autonomous distributed sensing node

    NASA Astrophysics Data System (ADS)

    Blottman, John B.; Richards, Roger T.

    2006-05-01

    The US Navy has recently placed emphasis on deployable, distributed sensors for Force Protection, Anti-Terrorism and Homeland Defense missions. The Naval Undersea Warfare Center has embarked on the development of a self-contained deployable node that is composed of electro-active polymers (EAP) for use in a covert persistent distributed surveillance system. Electro-Active Polymers (EAP) have matured to a level that permits their application in energy harvesting, hydrophones, electro-elastic actuation and electroluminescence. The problem to resolve is combining each of these functions into an autonomous sensing platform. The concept presented here promises an operational life several orders of magnitude beyond what is expected of a Sonobuoy due to energy conservation and harvesting, and at a reasonable cost. The embodiment envisioned is that of a deployed device resembling a jellyfish, made in most part of polymers, with the body encapsulating the necessary electronic processing and communications package and the tentacles of the jellyfish housing the sonar sensors. It will be small, neutrally buoyant, and will survey the water column much in the manner of a Cartesian Diver. By using the Electro-Active Polymers as artificial muscles, the motion of the jellyfish can be finely controlled. An increased range of detection and true node autonomy is achieved through volumetric array beamforming to focus the direction of interrogation and to null-out extraneous ambient noise.

  9. Structural and physical properties of collagen extracted from moon jellyfish under neutral pH conditions.

    PubMed

    Miki, Ayako; Inaba, Satomi; Baba, Takayuki; Kihira, Koji; Fukada, Harumi; Oda, Masayuki

    2015-01-01

    We extracted collagen from moon jellyfish under neutral pH conditions and analyzed its amino acid composition, secondary structure, and thermal stability. The content of hydroxyproline was 4.3%, which is lower than that of other collagens. Secondary structure analysis using circular dichroism (CD) showed a typical collagen helix. The thermal stability of this collagen at pH 3.0 was lower than those from fish scale and pig skin, which also correlates closely with jellyfish collagen having lower hydroxyproline content. Because the solubility of jellyfish collagen used in this study at neutral pH was quite high, it was possible to analyze its structural and physical properties under physiological conditions. Thermodynamic analysis using CD and differential scanning calorimetry showed that the thermal stability at pH 7.5 was higher than at pH 3.0, possibly due to electrostatic interactions. During the process of unfolding, fibrillation would occur only at neutral pH.

  10. Simultaneous measurements of jellyfish bell kinematics and flow fields using PTV and PIV

    NASA Astrophysics Data System (ADS)

    Xu, Nicole; Dabiri, John

    2016-11-01

    A better understanding of jellyfish swimming can potentially improve the energy efficiency of aquatic vehicles or create biomimetic robots for ocean monitoring. Aurelia aurita is a simple oblate invertebrate composed of a flexible bell and coronal muscle, which contracts to eject water from the subumbrellar volume. Jellyfish locomotion can be studied by obtaining body kinematics or by examining the resulting fluid velocity fields using particle image velocimetry (PIV). Typically, swim kinematics are obtained by semi-manually tracking points of interest (POI) along the bell in video post-processing; simultaneous measurements of kinematics and flows involve using this semi-manual tracking method on PIV videos. However, we show that both the kinematics and flow fields can be directly visualized in 3D space by embedding phosphorescent particles in animals free-swimming in seeded environments. Particle tracking velocimetry (PTV) can then be used to calculate bell kinematics, such as pulse frequency, bell deformation, swim trajectories, and propulsive efficiency. By simultaneously tracking POI within the bell and collecting PIV data, we can further study the jellyfish's natural locomotive control mechanisms in conjunction with flow measurements. NSF GRFP.

  11. Lessons learned from the jellyfish: Fluid transport at intermediate Reynolds numbers

    NASA Astrophysics Data System (ADS)

    Nawroth, Janna; Dabiri, John

    2011-11-01

    Biologically inspired hydrodynamic propulsion and maneuvering strategies promise the advancement of medical implants and novel robotic tools. We have chosen juvenile jellyfish as a model system for investigating fluid dynamics and morphological properties underlying fluid transport by an elastic system at intermediate Reynolds numbers. Recently we have described how natural variations in viscous forces are balanced by changes in jellyfish body shape (phenotypic plasticity), to the effect of facilitating efficient body-fluid interaction. Complementing these studies in our live model organisms, we are also engaged in engineering a synthetic jellyfish, that is, a rhythmically actuated elastomer capable of generating efficient feeding and propulsion currents. The main challenges here are (1) to derive a body shape and deformation suitable for effective fluid transport under physiological fluid conditions, (2) to understand the mechanical properties of actuator and elastomer to derive a design capable of the desired deformation, (3) to establish adequate 3D kinematics of power and recovery stroke, and (4) to evaluate the performance of the design.

  12. The in vivo cardiovascular effects of an Australasian box jellyfish (Chiropsalmus sp.) venom in rats.

    PubMed

    Ramasamy, Sharmaine; Isbister, Geoffrey K; Seymour, Jamie E; Hodgson, Wayne C

    2005-03-01

    Using a new technique to extract venom from the nematocysts of jellyfish, the in vivo cardiovascular effects of Chiropsalmus sp. venom were investigated in anaesthetized rats. Chiropsalmus sp. venom (150 microg/kg, i.v.) produced a transient hypertensive response (44+/-4 mmHg; n=6) followed by hypotension and cardiovascular collapse. Concurrent artificial respiration or pretreatment with Chironex fleckeri antivenom (AV, 3000 U/kg, i.v.) did not have any effect on the venom-induced hypertensive response nor the subsequent cardiovascular collapse. The cardiovascular response of animals receiving venom after the infusion of MgSO4 (50-70 mM @ 0.25 ml/min, i.v.; n=5) alone, or in combination with AV (n=5), was not significantly different from rats receiving venom alone. Prior administration of prazosin (50 microg/kg, i.v.; n=4) or ketanserin (1 mg/kg, i.v.; n=4) did not significantly attenuate the hypertensive response nor prevent the cardiovascular collapse induced by venom (50 microg/kg, i.v.). In contrast to previous work examining C. fleckeri venom, administration of AV alone, or in combination with MgSO4, was not effective in preventing cardiovascular collapse following the administration of Chiropsalmus sp. venom. This indicates that the venom of the two related box jellyfish contain different lethal components and highlights the importance of species identification prior to initiating treatment regimes following jellyfish envenoming.

  13. Formula-Based Public School Funding System in Victoria: An Empirical Analysis of Equity

    ERIC Educational Resources Information Center

    Bandaranayake, Bandara

    2013-01-01

    This article explores the formula-based school funding system in the state of Victoria, Australia, where state funds are directly allocated to schools based on a range of equity measures. The impact of Victoria' funding system for education in terms of alleviating inequality and disadvantage is contentious, to say the least. It is difficult to…

  14. A Snapshot: Multicultural Music Teaching in Schools in Victoria, Australia, Portrayed by School Teachers

    ERIC Educational Resources Information Center

    Nethsinghe, Rohan Nishantha

    2012-01-01

    Due to the changing demographic factors and as demanded by the governmental policies and regulations, schools in Victoria, Australia, are expected to foster multicultural educational programs that address the diverse needs of students. Research has found that school teachers in Victoria struggle to provide the aspired to multicultural education…

  15. Events Management Education through CD-ROM Simulation at Victoria University of Technology.

    ERIC Educational Resources Information Center

    Perry, Marcia; And Others

    There has been a rapid growth in the events industry in Victoria and Australia over the past five years with an increase in large scale events--resulting in substantive economic impact. The growth in events in Australia is projected to continue to beyond 2001. The Department of Management at Victoria University of Technology (VU) received a…

  16. 78 FR 48373 - Approval and Promulgation of Air Quality Implementation Plans; Texas; Victoria County; 1997 8...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-08

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Texas; Victoria... Implementation Plan (SIP). The revision consists of a maintenance plan for Victoria County developed to...

  17. 78 FR 76403 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel VICTORIA; Invitation for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Maritime Administration Requested Administrative Waiver of the Coastwise Trade Laws: Vessel VICTORIA... of the vessel VICTORIA is: Intended Commercial Use Of Vessel: ``Carrying up to 12 passengers for...

  18. Signatures of active and passive optimized Lévy searching in jellyfish.

    PubMed

    Reynolds, Andy M

    2014-10-06

    Some of the strongest empirical support for Lévy search theory has come from telemetry data for the dive patterns of marine predators (sharks, bony fishes, sea turtles and penguins). The dive patterns of the unusually large jellyfish Rhizostoma octopus do, however, sit outside of current Lévy search theory which predicts that a single search strategy is optimal. When searching the water column, the movement patterns of these jellyfish change over time. Movement bouts can be approximated by a variety of Lévy and Brownian (exponential) walks. The adaptive value of this variation is not known. On some occasions movement pattern data are consistent with the jellyfish prospecting away from a preferred depth, not finding an improvement in conditions elsewhere and so returning to their original depth. This 'bounce' behaviour also sits outside of current Lévy walk search theory. Here, it is shown that the jellyfish movement patterns are consistent with their using optimized 'fast simulated annealing'--a novel kind of Lévy walk search pattern--to locate the maximum prey concentration in the water column and/or to locate the strongest of many olfactory trails emanating from more distant prey. Fast simulated annealing is a powerful stochastic search algorithm for locating a global maximum that is hidden among many poorer local maxima in a large search space. This new finding shows that the notion of active optimized Lévy walk searching is not limited to the search for randomly and sparsely distributed resources, as previously thought, but can be extended to embrace other scenarios, including that of the jellyfish R. octopus. In the presence of convective currents, it could become energetically favourable to search the water column by riding the convective currents. Here, it is shown that these passive movements can be represented accurately by Lévy walks of the type occasionally seen in R. octopus. This result vividly illustrates that Lévy walks are not necessarily

  19. Signatures of active and passive optimized Lévy searching in jellyfish

    PubMed Central

    Reynolds, Andy M.

    2014-01-01

    Some of the strongest empirical support for Lévy search theory has come from telemetry data for the dive patterns of marine predators (sharks, bony fishes, sea turtles and penguins). The dive patterns of the unusually large jellyfish Rhizostoma octopus do, however, sit outside of current Lévy search theory which predicts that a single search strategy is optimal. When searching the water column, the movement patterns of these jellyfish change over time. Movement bouts can be approximated by a variety of Lévy and Brownian (exponential) walks. The adaptive value of this variation is not known. On some occasions movement pattern data are consistent with the jellyfish prospecting away from a preferred depth, not finding an improvement in conditions elsewhere and so returning to their original depth. This ‘bounce’ behaviour also sits outside of current Lévy walk search theory. Here, it is shown that the jellyfish movement patterns are consistent with their using optimized ‘fast simulated annealing’—a novel kind of Lévy walk search pattern—to locate the maximum prey concentration in the water column and/or to locate the strongest of many olfactory trails emanating from more distant prey. Fast simulated annealing is a powerful stochastic search algorithm for locating a global maximum that is hidden among many poorer local maxima in a large search space. This new finding shows that the notion of active optimized Lévy walk searching is not limited to the search for randomly and sparsely distributed resources, as previously thought, but can be extended to embrace other scenarios, including that of the jellyfish R. octopus. In the presence of convective currents, it could become energetically favourable to search the water column by riding the convective currents. Here, it is shown that these passive movements can be represented accurately by Lévy walks of the type occasionally seen in R. octopus. This result vividly illustrates that Lévy walks are not

  20. Analysis of continuous GPS measurements from southern Victoria Land, Antarctica

    USGS Publications Warehouse

    Willis, Michael J.

    2007-01-01

    Several years of continuous data have been collected at remote bedrock Global Positioning System (GPS) sites in southern Victoria Land, Antarctica. Annual to sub-annual variations are observed in the position time-series. An atmospheric pressure loading (APL) effect is calculated from pressure field anomalies supplied by the European Centre for Medium-Range Weather Forecasts (ECMWF) model loading an elastic Earth model. The predicted APL signal has a moderate correlation with the vertical position time-series at McMurdo, Ross Island (International Global Navigation Satellite System Service (IGS) station MCM4), produced using a global solution. In contrast, a local solution in which MCM4 is the fiducial site generates a vertical time series for a remote site in Victoria Land (Cape Roberts, ROB4) which exhibits a low, inverse correlation with the predicted atmospheric pressure loading signal. If, in the future, known and well modeled geophysical loads can be separated from the time-series, then local hydrological loading, of interest for glaciological and climate applications, can potentially be extracted from the GPS time-series.

  1. On the Rim of 'Victoria Crater' (Vertical Projection)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA's Mars rover Opportunity reached the rim of 'Victoria Crater' in Mars' Meridiani Planum region with a 26-meter (85-foot) drive during the rover's 951st Martian day, or sol (Sept. 26, 2006). After the drive, the rover's navigation camera took the three exposures combined into this view of the crater's interior. This crater has been the mission's long-term destination for the past 21 Earth months.

    A half mile in the distance one can see about 20 percent of the far side of the crater framed by the rocky cliffs in the foreground to the left and right of the image. The rim of the crater is composed of alternating promontories, rocky points towering approximately 70 meters (230 feet) above the crater floor, and recessed alcoves. The bottom of the crater is covered by sand that has been shaped into ripples by the Martian wind.

    The position at the end of the sol 951 drive is about six meters from the lip of an alcove called 'Duck Bay.' The rover team planned a drive for sol 952 that would move a few more meters forward, plus more imaging of the near and far walls of the crater.

    Victoria Crater is about five times wider than 'Endurance Crater,' which Opportunity spent six months examining in 2004, and about 40 times wider than 'Eagle Crater,' where Opportunity first landed.

    This view is presented as a vertical projection with geometric seam correction.

  2. On the Rim of 'Victoria Crater' (Polar Projection)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA's Mars rover Opportunity reached the rim of 'Victoria Crater' in Mars' Meridiani Planum region with a 26-meter (85-foot) drive during the rover's 951st Martian day, or sol (Sept. 26, 2006). After the drive, the rover's navigation camera took the three exposures combined into this view of the crater's interior. This crater has been the mission's long-term destination for the past 21 Earth months.

    A half mile in the distance one can see about 20 percent of the far side of the crater framed by the rocky cliffs in the foreground to the left and right of the image. The rim of the crater is composed of alternating promontories, rocky points towering approximately 70 meters (230 feet) above the crater floor, and recessed alcoves. The bottom of the crater is covered by sand that has been shaped into ripples by the Martian wind.

    The position at the end of the sol 951 drive is about six meters from the lip of an alcove called 'Duck Bay.' The rover team planned a drive for sol 952 that would move a few more meters forward, plus more imaging of the near and far walls of the crater.

    Victoria Crater is about five times wider than 'Endurance Crater,' which Opportunity spent six months examining in 2004, and about 40 times wider than 'Eagle Crater,' where Opportunity first landed.

    This view is presented as a polar projection with geometric seam correction.

  3. Jellyfish as prey: frequency of predation and selective foraging of Boops boops (Vertebrata, Actinopterygii) on the mauve stinger Pelagia noctiluca (Cnidaria, Scyphozoa).

    PubMed

    Milisenda, Giacomo; Rosa, Sara; Fuentes, Veronica L; Boero, Ferdinando; Guglielmo, Letterio; Purcell, Jennifer E; Piraino, Stefano

    2014-01-01

    In recent years, jellyfish blooms have attracted considerable scientific interest for their potential impacts on human activities and ecosystem functioning, with much attention paid to jellyfish as predators and to gelatinous biomass as a carbon sink. Other than qualitative data and observations, few studies have quantified direct predation of fish on jellyfish to clarify whether they may represent a seasonally abundant food source. Here we estimate predation frequency by the commercially valuable Mediterranean bogue, Boops boops on the mauve stinger jellyfish, Pelagia noctiluca, in the Strait of Messina (NE Sicily). A total of 1054 jellyfish were sampled throughout one year to quantify predation by B. boops from bite marks on partially eaten jellyfish and energy density of the jellyfish. Predation by B. boops in summer was almost twice that in winter, and they selectively fed according to medusa gender and body part. Calorimetric analysis and biochemical composition showed that female jellyfish gonads had significantly higher energy content than male gonads due to more lipids and that gonads had six-fold higher energy content than the somatic tissues due to higher lipid and protein concentrations. Energetically, jellyfish gonads represent a highly rewarding food source, largely available to B. boops throughout spring and summer. During the remainder of the year, when gonads were not very evident, fish predation switched towards less-selective foraging on the somatic gelatinous biomass. P. noctiluca, the most abundant jellyfish species in the Mediterranean Sea and a key planktonic predator, may represent not only a nuisance for human leisure activities and a source of mortality for fish eggs and larvae, but also an important resource for fish species of commercial value, such as B. boops.

  4. Jellyfish as Prey: Frequency of Predation and Selective Foraging of Boops boops (Vertebrata, Actinopterygii) on the Mauve Stinger Pelagia noctiluca (Cnidaria, Scyphozoa)

    PubMed Central

    Fuentes, Veronica L.; Boero, Ferdinando; Guglielmo, Letterio; Purcell, Jennifer E.; Piraino, Stefano

    2014-01-01

    In recent years, jellyfish blooms have attracted considerable scientific interest for their potential impacts on human activities and ecosystem functioning, with much attention paid to jellyfish as predators and to gelatinous biomass as a carbon sink. Other than qualitative data and observations, few studies have quantified direct predation of fish on jellyfish to clarify whether they may represent a seasonally abundant food source. Here we estimate predation frequency by the commercially valuable Mediterranean bogue, Boops boops on the mauve stinger jellyfish, Pelagia noctiluca, in the Strait of Messina (NE Sicily). A total of 1054 jellyfish were sampled throughout one year to quantify predation by B. boops from bite marks on partially eaten jellyfish and energy density of the jellyfish. Predation by B. boops in summer was almost twice that in winter, and they selectively fed according to medusa gender and body part. Calorimetric analysis and biochemical composition showed that female jellyfish gonads had significantly higher energy content than male gonads due to more lipids and that gonads had six-fold higher energy content than the somatic tissues due to higher lipid and protein concentrations. Energetically, jellyfish gonads represent a highly rewarding food source, largely available to B. boops throughout spring and summer. During the remainder of the year, when gonads were not very evident, fish predation switched towards less-selective foraging on the somatic gelatinous biomass. P. noctiluca, the most abundant jellyfish species in the Mediterranean Sea and a key planktonic predator, may represent not only a nuisance for human leisure activities and a source of mortality for fish eggs and larvae, but also an important resource for fish species of commercial value, such as B. boops. PMID:24727977

  5. QM/MM study on the light emitters of aequorin chemiluminescence, bioluminescence, and fluorescence: a general understanding of the bioluminescence of several marine organisms.

    PubMed

    Chen, Shu-Feng; Ferré, Nicolas; Liu, Ya-Jun

    2013-06-24

    Aequorea victoria is a type of jellyfish that is known by its famous protein, green fluorescent protein (GFP), which has been widely used as a probe in many fields. Aequorea has another important protein, aequorin, which is one of the members of the EF-hand calcium-binding protein family. Aequorin has been used for intracellular calcium measurements for three decades, but its bioluminescence mechanism remains largely unknown. One of the important reasons is the lack of clear and reliable knowledge about the light emitters, which are complex. Several neutral and anionic forms exist in chemiexcited, bioluminescent, and fluorescent states and are connected with the H-bond network of the binding cavity in the protein. We first theoretically investigated aequorin chemiluminescence, bioluminescence, and fluorescence in real proteins by performing hybrid quantum mechanics and molecular mechanics methods combined with a molecular dynamics method. For the first time, this study reported the origin and clear differences in the chemiluminescence, bioluminescence and fluorescence of aequorin, which is important for understanding the bioluminescence not only of jellyfish, but also of many other marine organisms (that have the same coelenterazine caved in different coelenterazine-type luciferases).

  6. Forty Meters from Entry to Victoria Crater (Vertical)

    NASA Technical Reports Server (NTRS)

    2007-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera during the rover's 1,278th Martian day, or sol, (Aug. 28, 2007) to take the images combined into this view. The rover was perched at the lip of Victoria Crater, which is about 800 meters (one-half mile) in diameter.

    After assessment of possible routes for Opportunity to descend into the crater, the rover team selected a site farther to the right along the rim. That selected entry point lies near the ripple of bright soil visible just outside the crater near the top center of this scene. The driving distance for Opportunity from the Sol 1,278 viewpoint to the selected entry point is about 40 meters (about 130 feet).

    This view is presented as a vertical projection with geometric seam correction.

  7. Forty Meters from Entry to Victoria Crater (Polar)

    NASA Technical Reports Server (NTRS)

    2007-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera during the rover's 1,278th Martian day, or sol, (Aug. 28, 2007) to take the images combined into this view. The rover was perched at the lip of Victoria Crater, which is about 800 meters (one-half mile) in diameter.

    After assessment of possible routes for Opportunity to descend into the crater, the rover team selected a site farther to the right along the rim. That selected entry point lies near the ripple of bright soil visible just outside the crater near the top center of this scene. The driving distance for Opportunity from the Sol 1,278 viewpoint to the selected entry point is about 40 meters (about 130 feet).

    This view is presented as a polar projection with geometric seam correction.

  8. Layers of 'Cabo Frio' in 'Victoria Crater' (Stereo)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This view of 'Victoria crater' is looking southeast from 'Duck Bay' towards the dramatic promontory called 'Cabo Frio.' The small crater in the right foreground, informally known as 'Sputnik,' is about 20 meters (about 65 feet) away from the rover, the tip of the spectacular, layered, Cabo Frio promontory itself is about 200 meters (about 650 feet) away from the rover, and the exposed rock layers are about 15 meters (about 50 feet) tall. This is a red-blue stereo anaglyph generated from images taken by the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity during the rover's 952nd sol, or Martian day, (Sept. 28, 2006) using the camera's 430-nanometer filters.

  9. Layers of 'Cape Verde' in 'Victoria Crater' (Enhanced)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This view of Victoria crater is looking north from 'Duck Bay' towards the dramatic promontory called 'Cape Verde.' The dramatic cliff of layered rocks is about 50 meters (about 165 feet) away from the rover and is about 6 meters (about 20 feet) tall. The taller promontory beyond that is about 100 meters (about 325 feet) away, and the vista beyond that extends away for more than 400 meters (about 1300 feet) into the distance. This is a false color rendering (enhanced to bring out details from within the shadowed regions of the scene) of images taken by the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity during the rover's 952nd sol, or Martian day, (Sept. 28, 2006) using the camera's 750-nanometer, 530-nanometer and 430-nanometer filters.

  10. Layers of 'Cape Verde' in 'Victoria Crater' (False Color)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This view of Victoria crater is looking north from 'Duck Bay' towards the dramatic promontory called 'Cape Verde.' The dramatic cliff of layered rocks is about 50 meters (about 165 feet) away from the rover and is about 6 meters (about 20 feet) tall. The taller promontory beyond that is about 100 meters (about 325 feet) away, and the vista beyond that extends away for more than 400 meters (about 1300 feet) into the distance. This is an enhanced false color rendering of images taken by the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity during the rover's 952nd sol, or Martian day, (Sept. 28, 2006) using the camera's 750-nanometer, 530-nanometer and 430-nanometer filters.

  11. Layers of 'Cape Verde' in 'Victoria Crater' (Stereo)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This view of Victoria crater is looking north from 'Duck Bay' towards the dramatic promontory called 'Cape Verde.' The dramatic cliff of layered rocks is about 50 meters (about 165 feet) away from the rover and is about 6 meters (about 20 feet) tall. The taller promontory beyond that is about 100 meters (about 325 feet) away, and the vista beyond that extends away for more than 400 meters (about 1300 feet) into the distance. This is a red-blue stereo anaglyph generated from images taken by the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity during the rover's 952nd sol, or Martian day, (Sept. 28, 2006) using the camera's 430-nanometer filters.

  12. Layers of 'Cabo Frio' in 'Victoria Crater' (False Color)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This view of 'Victoria crater' is looking southeast from 'Duck Bay' towards the dramatic promontory called 'Cabo Frio.' The small crater in the right foreground, informally known as 'Sputnik,' is about 20 meters (about 65 feet) away from the rover, the tip of the spectacular, layered, Cabo Frio promontory itself is about 200 meters (about 650 feet) away from the rover, and the exposed rock layers are about 15 meters (about 50 feet) tall. This is an enhanced false color rendering of images taken by the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity during the rover's 952nd sol, or Martian day, (Sept. 28, 2006) using the camera's 750-nanometer, 530-nanometer and 430-nanometer filters.

  13. Re-evaluation of the kinematics of Victoria Block using continuous GNSS data

    NASA Astrophysics Data System (ADS)

    Fernandes, R. M. S.; Miranda, J. M.; Delvaux, D.; Stamps, D. S.; Saria, E.

    2013-04-01

    The divergent boundary between the Somalia and Nubia plates is a complex tectonic domain where extensional processes are localized along narrow rift structures, isolating small blocks imbedded within the East African Rift. One of these tectonic units is the Victoria Block, which is the subject of this study. Here we process space-geodetic data for 37 permanent GNSS stations distributed along Nubia, Somalia and Victoria to (1) compute the motion of the three tectonic units in the ITRF2008 reference frame and (2) deduce the relative motion of Victoria with respect to its neighbouring plates. The Nubia Plate motion is computed from a set of 25 stations, the Somalia Plate motion from a set of 7 stations and the Victoria motion from a set of 5 stations. Although the number and distribution of the used stations is still not optimal, the good adjustment between observed and predicted motions confirms that Victoria acts as a rigid tectonic block. The instantaneous relative Euler poles for the Nubia-Victoria and Somalia-Victoria pairs are now evaluated as 10.66°N, 32.98E°, 0.120° Myr-1 and 8.02°S, 32.29°E, 0.159° Myr-1, respectively. The computation of the relative interplate velocities along Victoria's boundary is straightforward in most situations because the western and northeastern boundary segments correspond to well-developed rift basins, where extension is mostly normal to rift basin flanks and seismicity concentrates along narrow structures. This is particularly evident on the Western Branch between Victoria and Nubia. The southeastern limit of the Victoria Block is poorly defined, and geodetic data indicate that differential motion between Somalia and Victoria may be accommodated by a complex boundary area, which roughly encompasses the Masai Terrain. Geodetic observations of the Victoria-Somalia boundary along the Eastern Branch, particularly in the Manyara Rift, reveal highly oblique horizontal extension. In this region seismicity is sparse which suggests

  14. Health promotion in local churches in Victoria: an exploratory study.

    PubMed

    Ayton, Darshini; Manderson, Lenore; Smith, Ben J; Carey, Gemma

    2016-11-01

    Church-based health promotion has increasingly gained attention in strategies to address health disparities. In Australia, we have limited understanding of the role of local churches in health promotion and without this, how they might be involved in meaningful partnerships to tackle public health challenges. The objective of this qualitative study was to explore how churches are involved in health promotion in the state of Victoria. The research involved in-depth interviews with ministers from 30 churches in urban and rural Victoria, and case studies with 10 of these churches to enable further exploration. These case studies, conducted in 2010, included interviews with church staff, focus groups with volunteers, participant observation and document analysis. Analysis was iterative, utilising open, axial and thematic coding. Three different expressions of church - traditional, new modern and emerging - were identified and found to differentiate the levels and types of health promotion activity. Case studies illustrate the different expressions of how church mission influences health promotion activity. The traditional churches were involved particularly in disease screening and health education activities with their own, predominantly older congregation members. The new modern churches tended to have the material and human resources to be harnessed in health promotion activities involving congregation members and others. Emerging churches, in contrast, engaged in broad health-promoting activities, including disease prevention, lifestyle activities and socio-ecological approaches at a community level. These research findings highlight the opportunities and challenges of engaging with local churches in health promotion efforts and public health programmes to address health inequities.

  15. Offshore investigations on Wilkes land-Victoria land margin, Antarctica

    SciTech Connect

    Eittreim, S.L.

    1984-04-01

    In January 1984, the US Geological Survey research vessel S. P. Lee carried out investigations of the Antarctic continental margin in the Wilkes Land Victoria Land areas, using 24-channel and high-resolution seismic, sonobuoy refraction, gravity, magnetic, and bottom-sampling methods. This investigation augmented previous surveys of the Dumont d'Urville area by the French Petroleum Institute and explored new areas west and east to the boundary between the onshore Wilkes basin and the Victoria Land highlands. These surveys defined sediment thickness distribution and seismic stratigraphy in this frontier area. The tectonic style of the boundary between the East Antarctic craton and the younger crust of West Antarctica in the Ross Sea is revealed by one multichannel seismic line across this important boundary. The initial breakup of Antarctical from Australia occurred as a slowly spreading phase during the middle Cretaceous. According to Deep Sea Drilling Project results on the Tasman Rise, conditions of restricted circulation existed in the growing basin between the continents before the late Eocene. After the late Eocene, the major oceanic circulation pattern was established. Before that time, conditions were favorable for preservation of organic-carbon deposits on the sea floor. Among the questions to be addressed with this data are the following. How do apparent subsidence rates of this passive margin compare with others around the world. Does the onshore subglacial Wilkes basins to the Otway and Ceduna basins of Australia exists. What is the effect of the ice cap on the stratigraphy of this margin. Do the two major Tertiary ice advances have conspicuous seismic-stratigraphic signatures.

  16. PCBs in fish and their cestode parasites in Lake Victoria.

    PubMed

    Oluoch-Otiego, John; Oyoo-Okoth, Elijah; Kiptoo, Kipkorir Koross Godfrey; Chemoiwa, Emily J; Ngugi, Charles C; Simiyu, Gelas; Omutange, Elijah S; Ngure, Veronica; Opiyo, Mary A

    2016-08-01

    Polychlorinated biphenyls (PCBs) are classified as persistent organic pollutants (POPs) regulated by the Stockholm Convention (2001). Although their production and use was stopped almost three decades ago, PCBs are environmental persistent, toxic, and bioaccumulate in biota. We assessed the levels of 7 PCB congeners (IUPAC nos. 28, 52, 101, 118, 138, 153, and 180) in sediment and fish (Oreochromis niloticus, Lates niloticus, and Rastrineobola argentea) and evaluated the potential of cestode fish endoparasite (Monobothrioides sp., Proteocephalaus sp., and Ligula intestinalis) as biomonitors of PCBs in Lake Victoria, Kenya. The median concentration of Σ7PCBs in sediments and fish were 2.2-96.3 μg/kg dw and 300-3,000 μg/kg lw, respectively. At all the sampling sites, CB138, CB153, and CB180 were the dominant PCB congeners in sediment and fish samples. Compared to the muscle of the piscine host, Proteocephalaus sp. (infecting L. niloticus) biomagnified PCBs ×6-14 while Monobothrioides sp. (infecting O. niloticus) biomagnified PCBs ×4-8. Meanwhile, L. intestinalis (infecting R. argentea) biomagnified PCBs ×8-16 compared to the muscle of unparasitized fish. We demonstrate the occurrence of moderate to high levels of PCB in sediments and fish in Lake Victoria. We also provide evidence that fish parasites bioaccumulate higher levels of PCBs than their piscine hosts and therefore provide a promising biomonitor of PCBs. We urge further a long-term study to validate the use of the above cestode fish parasites as biomonitoring tools for PCBs.

  17. Impact of Land Use on Soil Respiration in Southwestern Victoria

    NASA Astrophysics Data System (ADS)

    Teodosio, B.; Daly, E.; Pauwels, V. R. N.

    2015-12-01

    Land use management is one of the key contributors to the global environmental change. Considerable changes in landscapes have been experienced in Southwestern Victoria, Australia in the past two decades. Eucalyptus globulus (blue gum) plantations have expanded, resulting in possible changes in the water and carbon balances of catchments. The shift from pastures to plantations could have a significant impact on the local carbon balance with possible effects on atmospheric CO2 concentration and vegetation productivity. We present preliminary measurements from a field study comparing soil respiration in a plantation and a pasture. Adjacent catchments in Southwestern Victoria, near Gatum, were used as study areas; the prominent difference between the two catchments is the land use, with one catchment being used as a pasture for livestock grazing and the other catchment being mainly planted with blue gums. The variability of soil respiration in the pasture is governed by differences in soil moisture and substrate content due to local features of the topography and livestock grazing. Soil respiration measurements in the plantation were taken on mounds, access tracks, and open spaces. Most observations on mounds had higher soil respiration possibly due to root and mycorrhizal respiration. The measurements in open spaces had comparable values with mound measurements; this might be due to a less limited radiation. The soil respiration between trees had lower values, possibly because of radiation limitation due to the canopy cover. These preliminary measurements allow us to compare soil respiration variability across catchments with different land uses. This is important to estimate CO2 fluxes from soil to the atmosphere in large areas and will be valuable in estimating gross primary production from measurements of net ecosystem exchange.

  18. The ontogenetic scaling of hydrodynamics and swimming performance in jellyfish (Aurelia aurita).

    PubMed

    McHenry, Matthew J; Jed, Jason

    2003-11-01

    It is not well understood how ontogenetic changes in the motion and morphology of aquatic animals influence the performance of swimming. The goals of the present study were to understand how changes in size, shape and behavior affect the hydrodynamics of jet propulsion in the jellyfish Aurelia aurita and to explore how such changes affect the ontogenetic scaling of swimming speed and cost of transport. We measured the kinematics of jellyfish swimming from video recordings and simulated the hydrodynamics of swimming with two computational models that calculated thrust generation by paddle and jet mechanisms. Our results suggest that thrust is generated primarily by jetting and that there is negligible thrust generation by paddling. We examined how fluid forces scaled with body mass using the jet model. Despite an ontogenetic increase in the range of motion by the bell diameter and a decrease in the height-to-diameter ratio, we found that thrust and acceleration reaction scaled with body mass as predicted by kinematic similarity. However, jellyfish decreased their pulse frequency with growth, and speed consequently scaled at a lower exponential rate than predicted by kinematic similarity. Model simulations suggest that the allometric growth in Aurelia results in swimming that is slower, but more energetically economical, than isometric growth with a prolate bell shape. The decrease in pulse frequency over ontogeny allows large Aurelia medusae to avoid a high cost of transport but generates slower swimming than if they maintained a high pulse frequency. Our findings suggest that ontogenetic change in the height-to-diameter ratio and pulse frequency of Aurelia results in swimming that is relatively moderate in speed but is energetically economical.

  19. Development studies of Aurelia (jellyfish) ephyrae which developed during the SLS-1 mission

    NASA Technical Reports Server (NTRS)

    Spangenberg, D. B.; Jernigan, T.; Mccombs, R.; Lowe, B. T.; Sampson, M.; Slusser, J.

    1994-01-01

    Aurelia polyps (scyphistomae) and ephyrae were exposed to microgravity for nine days aboard the space shuttle during the SLS-1 mission. During strobilation, polyps segment transversely and each segment develops into an ephyra. Polyps were induced to strobilate at 28 C, using iodine or thyroxine, at L(Launch)-48h, L-24h, and L+8h. Ephyrae developed in the groups tested in space and on Earth. The number of ephyrae formed per polyp was slightly higher in the L+8h groups as compared with those induced at L-24h and L-48h. On Earth, iodine is used by jellyfish to synthesize jellyfish-thyroxine (Jf T(sub 4)), needed for ephyra production. Since iodine-treated polyps strobilated and formed ephyrae in space, it appears that jellyfish can synthesize Jf-T(sub 4) in space. Indeed, two groups of polyps not given inducer formed ephryae in space, presumably due to enhanced Jf-T(sub 4) synthesis, utilization or accumulation. Some ephyrae that formed in space were also fixed in space on Mission Day (MD) 8; others were fixed post-flight. Examination of living ephyrae with the light microscope and fixed ones with the Scanning and Transmission Electron Microscopes revealed that those which developed in space were morphologically very similar to those which developed on Earth. Quantitation of arm numbers determined that there were no significant differences between space and Earth-developed ephyrae. Pulsing abnormalities, however, were found in greater number (18.3%) in space-developed ephyrae than in Earth-developed controls (2.9%). These abnormalities suggest abnormal development of the graviceptors, the neuromuscular system, or a defect in the integration between these systems in apparently microgravity-sensitive animals.

  20. Speciation and isotopic composition of sulfur in sediments from Jellyfish Lake, Palau

    USGS Publications Warehouse

    Bates, A.L.; Spiker, E. C.; Orem, W.H.; Burnett, W.C.

    1993-01-01

    Jellyfish Lake, Palau, is a meromictic marine lake with high organic productivity, low reactive Fe content, and anoxic bottom waters. Sediment samples from Jellyfish Lake were examined for the distribution of sulfur species and their isotopic signatures in order to gain a better understanding of sedimentary sulfur incorporation in Fe-poor environments. Surface samples were taken along a transect from a near-shore site to the center of the lake, and include a sample below oxic water, a sample below the chemocline layer, and samples below anoxic waters. Three additional samples were taken from a core, 2 m long, collected near the lake center. Sulfur to organic carbon weight ratios in all samples were lower than the expected value of 0.36 for normal marine sediment, probably because the lake water is deficient in reactive Fe to form iron sulfides. Total sulfur contents in the surface sediments indicated no changes with distance from shore; however, the sulfur content of the surface sample at the chemocline layer may be slightly higher. Total sulfur content increased with depth in the core and is inversely related to organic carbon content. Organic sulfur is the major sulfur species in the samples, followed in descending order by sulfate, disulfides and monosulfides. Sulfate sulfur isotope ??34S-values are positive (from +20.56 to +12.04???), reflecting the marine source of sulfate in Jellyfish Lake. Disulfide and monosulfide ??34S-values are negative (from -25.07 to -7.60???), because of fractionation during bacterial reduction of sulfate. Monosulfide ??34S-values are somewhat higher than those of disulfides, and they are close to the ??34S-values of organic sulfur. These results indicate that most of the organic sulfur is formed by reaction of bacteriogenic monosulfides, or possibly monosulfide-derived polysulfides, with organic matter in the sediment. ?? 1993.

  1. Ecosystem relevance of variable jellyfish biomass in the Irish Sea between years, regions and water types

    NASA Astrophysics Data System (ADS)

    Bastian, Thomas; Lilley, Martin K. S.; Beggs, Steven E.; Hays, Graeme C.; Doyle, Thomas K.

    2014-08-01

    Monitoring the abundance and distribution of taxa is essential to assess their contribution to ecosystem processes. For marine taxa that are difficult to study or have long been perceived of little ecological importance, quantitative information is often lacking. This is the case for jellyfish (medusae and other gelatinous plankton). In the present work, 4 years of scyphomedusae by-catch data from the 2007-2010 Irish Sea juvenile gadoid fish survey were analysed with three main objectives: (1) to provide quantitative and spatially-explicit species-specific biomass data, for a region known to have an increasing trend in jellyfish abundance; (2) to investigate whether year-to-year changes in catch-biomass are due to changes in the numbers or in the size of medusa (assessed as the mean mass per individual), and (3) to determine whether inter-annual variation patterns are consistent between species and water masses. Scyphomedusae were present in 97% of samples (N = 306). Their overall annual median catch-biomass ranged from 0.19 to 0.92 g m-3 (or 8.6 to 42.4 g m-2). Aurelia aurita and Cyanea spp. (Cyanea lamarckii and Cyanea capillata) made up 77.7% and 21.5% of the total catch-biomass respectively, but species contributions varied greatly between sub-regions and years. No consistent pattern was detected between the distribution and inter-annual variations of the two genera, and contrasting inter-annual patterns emerged when considering abundance either as biomass or as density. Significantly, A. aurita medusae were heavier in stratified than in mixed waters, which we hypothesize may be linked to differences in timing and yield of primary and secondary productions between water masses. These results show the vulnerability of time-series from bycatch datasets to phenological changes and highlight the importance of taking species- and population-specific distribution patterns into account when integrating jellyfish into ecosystem models.

  2. In vivo analysis of effects of venom from the jellyfish Chrysaora sp. in zebrafish (Danio rerio).

    PubMed

    Becerra-Amezcua, Mayra P; Guerrero-Legarreta, Isabel; González-Márquez, Humberto; Guzmán-García, Xochitl

    2016-04-01

    The jellyfishes of the genus Chrysaora are present in all of the world's oceans, but the toxicity of their venoms has not yet been thoroughly characterized. The zebrafish as a toxicology model can be used for general toxicity testing of drugs and the investigation of toxicological mechanisms. The aim of this study was to evaluate the effect of crude venom from jellyfish Chrysaora sp., a species of jellyfish observed in the tropical lagoons of the Gulf of Mexico, on the zebrafish Danio rerio. Juvenile zebrafish were injected with different concentrations of venom from Chrysaora sp. via intraperitoneal and subcutaneous injections. The effects of the venom were determined by histopathological analysis and through the measurement of hemolytic and phospholipase A2 activities. The crude venom was examined by SDS-PAGE. The effect of sublethal concentrations of crude venom from Chrysaora sp. on D. rerio was hemorrhaging in the eyes, while the histopathological analysis demonstrated that the primary organs targeted were the pseudobranch, which displayed hyperemia, and the gill, which displayed hyperplasia and hypertrophy. The blood analysis exhibited hemolysis, nuclear abnormalities, and echinocytes by the action of phospholipase A2, which was determined to have 596 units of activity/mg of protein in the venom. The crude venom has proteins with molecular weights ranging from 250 to 6 kDa, with more density in the bands corresponding to 70, 20 and 15 kDa. The venom of Chysaora sp. caused disturbances in circulation associated with vascular dilation due to the localized release of inflammatory mediators. The hemolysis of erythrocytes was caused by the action of phospholipase A2. These findings not only provide an excellent study model but also have a great pharmacological potential for designing new drugs and for the elucidation of the mechanisms of action of and treatment against stings.

  3. Jellyfish: Observational Properties of Extreme Ram-Pressure Stripping Events in Massive Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Conor, McPartland; Ebeling, Harald; Roediger, Elke

    2015-08-01

    We investigate the physical origin and observational signatures of extreme ram-pressure stripping (RPS) in 63 massive galaxy clusters at z=0.3-0.7, based on data in the F606W passband obtained with the Advanced Camera for Surveys aboard the Hubble Space Telescope. Using a training set of a dozen ``jellyfish" galaxies identified earlier in the same imaging data, we define quantitative morphological criteria to select candidate galaxies which are similar to known cases of RPS. Considering a sample of 16 ``jellyfish" galaxies (10 of which we present for the first time), we visually derive estimates of the projected direction of motion based on dynamical features such as apparent compression shocks and debris trails. Our findings suggest that the observed events occur primarily at large distances from the cluster core and involve infall trajectories featuring high impact parameters. Simple models of cluster growth show that such trajectories are consistent with two scenarios: 1) galaxy infall along filaments; and 2) infall at high velocities (≥1000 km/s) characteristic of cluster mergers. The observed distribution of events is best described by timescales of ˜few Myr in agreement with recent numerical simulations of RPS. The broader areal coverage of the Hubble Frontier Fields should provide an even larger sample of RPS events to determine the relative contributions of infall and cluster mergers. Prompted by the discovery of several jellyfish galaxies whose brightness in the F606W passband rivals or exceeds that of the respective brightest cluster galaxy, we attempt to constrain the luminosity function of galaxies undergoing RPS. The observed significant excess at the bright end compared to the luminosity functions of blue cluster members strongly suggests enhanced star formation, thus challenging theoretical and numerical studies according to which RPS merely displaces existing star-forming regions. In-depth studies of individual objects will help test our

  4. Reduced salinity increases susceptibility of zooxanthellate jellyfish to herbicide toxicity during a simulated rainfall event.

    PubMed

    Klein, Shannon G; Pitt, Kylie A; Carroll, Anthony R

    2016-02-01

    Accurately predicting how marine biota are likely to respond to changing ocean conditions requires accurate simulation of interacting stressors, exposure regimes and recovery periods. Jellyfish populations have increased in some parts of the world and, despite few direct empirical tests, are hypothesised to be increasing because they are robust to a range of environmental stressors. Here, we investigated the effects of contaminated runoff on a zooxanthellate jellyfish by exposing juvenile Cassiopea sp. medusae to a photosystem II (PSII) herbicide, atrazine and reduced salinity conditions that occur following rainfall. Four levels of atrazine (0ngL(-1), 10ngL(-1), 2μgL(-1), 20μgL(-1)) and three levels of salinity (35 ppt, 25 ppt, 17 ppt) were varied, mimicking the timeline of light, moderate and heavy rainfall events. Normal conditions were then slowly re-established over four days to mimic the recovery of the ecosystem post-rain and the experiment continued for a further 7 days to observe potential recovery of the medusae. Pulse-amplitude modulated (PAM) chlorophyll fluorescence, growth and bell contraction rates of medusae were measured. Medusae exposed to the combination of high atrazine and lowest salinity died. After 3 days of exposure, bell contraction rates were reduced by 88% and medusae were 16% smaller in the lowest salinity treatments. By Day 5 of the experiment, all medusae that survived the initial pulse event began to recover quickly. Although atrazine decreased YII under normal salinity conditions, YII was further reduced when medusae were exposed to both low salinity and atrazine simultaneously. Atrazine breakdown products were more concentrated in jellyfish tissues than atrazine at the end of the experiment, suggesting that although bioaccumulation occurred, atrazine was metabolised. Our results suggest that reduced salinity may increase the susceptibility of medusae to herbicide exposure during heavy rainfall events.

  5. Complete mitochondrial genome of the moon jellyfish, Aurelia sp. nov. (Cnidaria, Scyphozoa).

    PubMed

    Hwang, Dae-Sik; Park, Eunji; Won, Yong-Jin; Lee, Jae-Seong

    2014-02-01

    We sequenced 16,971 bp of the linear mitochondrial DNA of the moon jellyfish Aurelia sp. nov. and characterized it by comparing with Aurelia aurita. They had 13 protein-coding genes (PCGs), 16S rRNA and 12S rRNA with three tRNAs (tRNA-Leu, tRNA-Ser(TGA), tRNA-Met). Both have another two PCGs, orf969 and orf324 with telomeres at both ends. After comparison of Aurelia sp. nov. with Aurelia aurita, we found low-protein similarity of orf969 (59%) and orf324 (75%), respectively, while the other 13 PCGs showed 80% to 98% protein similarities.

  6. Analyzing Beach Recreationists' Preferences for the Reduction of Jellyfish Blooms: Economic Results from a Stated-Choice Experiment in Catalonia, Spain.

    PubMed

    Nunes, Paulo A L D; Loureiro, Maria L; Piñol, Laia; Sastre, Sergio; Voltaire, Louinord; Canepa, Antonio

    2015-01-01

    Jellyfish outbreaks and their consequences appear to be on the increase around the world, and are becoming particularly relevant in the Mediterranean. No previous studies have quantified tourism losses caused by jellyfish outbreaks. We used a stated-choice questionnaire and a Random Utility Model to estimate the amount of time respondents would be willing to add to their journey, in terms of reported extra travel time, in order to reduce the risk of encountering jellyfish blooms in the Catalan coast. The estimation results indicated that the respondents were willing to spend on average an additional 23.8% of their travel time to enjoy beach recreation in areas with a lower risk of jellyfish blooms. Using as a reference the opportunity cost of time, we found that the subsample of individuals who made a trade-off between the disutility generated by travelling longer in order to lower the risk of jellyfish blooms, and the utility gained from reducing this risk, are willing to pay on average €3.20 per beach visit. This estimate, combined with the respondents' mean income, yielded annual economic gains associated with reduction of jellyfish blooms on the Catalan coast around €422.57 million, or about 11.95% of the tourism expenditures in 2012. From a policy-making perspective, this study confirms the importance of the economic impacts of jellyfish blooms and the need for mitigation strategies. In particular, providing daily information using social media applications or other technical devices may reduce these social costs. The current lack of knowledge about jellyfish suggests that providing this information to beach recreationists may be a substantially effective policy instrument for minimising the impact of jellyfish blooms.

  7. Analyzing Beach Recreationists’ Preferences for the Reduction of Jellyfish Blooms: Economic Results from a Stated-Choice Experiment in Catalonia, Spain

    PubMed Central

    Nunes, Paulo A. L. D.; Loureiro, Maria L.; Piñol, Laia; Sastre, Sergio; Voltaire, Louinord; Canepa, Antonio

    2015-01-01

    Jellyfish outbreaks and their consequences appear to be on the increase around the world, and are becoming particularly relevant in the Mediterranean. No previous studies have quantified tourism losses caused by jellyfish outbreaks. We used a stated-choice questionnaire and a Random Utility Model to estimate the amount of time respondents would be willing to add to their journey, in terms of reported extra travel time, in order to reduce the risk of encountering jellyfish blooms in the Catalan coast. The estimation results indicated that the respondents were willing to spend on average an additional 23.8% of their travel time to enjoy beach recreation in areas with a lower risk of jellyfish blooms. Using as a reference the opportunity cost of time, we found that the subsample of individuals who made a trade-off between the disutility generated by travelling longer in order to lower the risk of jellyfish blooms, and the utility gained from reducing this risk, are willing to pay on average €3.20 per beach visit. This estimate, combined with the respondents’ mean income, yielded annual economic gains associated with reduction of jellyfish blooms on the Catalan coast around €422.57 million, or about 11.95% of the tourism expenditures in 2012. From a policy-making perspective, this study confirms the importance of the economic impacts of jellyfish blooms and the need for mitigation strategies. In particular, providing daily information using social media applications or other technical devices may reduce these social costs. The current lack of knowledge about jellyfish suggests that providing this information to beach recreationists may be a substantially effective policy instrument for minimising the impact of jellyfish blooms. PMID:26053674

  8. Modified Aequorin Shows Increased Bioluminescence Activity

    DTIC Science & Technology

    1993-08-18

    LW. Schultz, J.R. Deschamps, and KB. Ward. Preparation and Initial Characterization of Crystals of the Photoprotein Aequorin from Aequorea victoria ...C. Prasher, Virginia K Eckenrode, William W. Ward, Frank G. Prendergast, and Milton J. Cormier. Primary structure of the Aequorea victoria green...Prendergast, and William W. Ward. Chemical Structure of the Hexapeptide Chromophore of the Aequorea Green- Fluorescent Protein. Biochemistry 32: 1 212

  9. Modified Aequorin Shows Increased Bioluminescence Activity

    DTIC Science & Technology

    1993-08-18

    and Initial Characterization of Crystals of the Photoprotein Aequorin from Aequorea victoria . Proteins, Structure, & Genetics 15: 103-107. RELATED...Frank G. Prendergast, and Milton J. Cormier. Primary structure of the Aequorea victoria green-fluorescent protein. Gene 111 (2):229-233. PATENTS U.S...Hexapeptide Chromophore of the Aequorea Green- Fluorescent Protein. Biochemistry 32: 1212-1218. 1992 Dennis J. O’Kane, and Douglas C. Prasher

  10. Isolation and in vitro partial characterization of hemolytic proteins from the nematocyst venom of the jellyfish Stomolophus meleagris.

    PubMed

    Li, Rongfeng; Yu, Huahua; Xing, Ronge; Liu, Song; Qing, Yukun; Li, Kecheng; Li, Bing; Meng, Xiangtao; Cui, Jinhui; Li, Pengcheng

    2013-09-01

    Jellyfish venom contains various toxins and can cause itching, edema, muscle aches, shortness of breath, blood pressure depression, shock or even death after being stung. Hemolytic protein is one of the most hazardous components in the venom. The present study investigated the hemolytic activity of the nematocyst venom from jellyfish Stomolophus meleagris. Anion exchange chromatography, DEAE Sepharose Fast Flow, and gel filtration chromatography, Superdex200 had been employed to isolate hemolytic proteins from the nematocyst venom of jellyfish S. meleagris. Hemolysis of chicken red blood cells was used to quantify hemolytic potency of crude nematocyst venom and chromatography fractions during the purification process. Native-PAGE profile displayed one protein band in the purified hemolytic protein (SmTX); however, two protein bands with apparent molecular weights of ≈ 45 kDa and 52 kDa were observed in the reducing SDS-PAGE analysis. Approximately 70 μg/mL of SmTX caused 50% hemolysis (HU50) of the erythrocyte suspension. The hemolytic activity of SmTX was shown to be temperature and pH dependent, with the optimum temperature and pH being 37°C and pH 5.0. The present study is the first report of isolation and partial characterization of hemolytic proteins from the nematocyst venom of the jellyfish S. meleagris. The mechanism of the hemolytic activity of SmTX is not clear and deserves further investigation.

  11. Sensitivity analysis of the GNSS derived Victoria plate motion

    NASA Astrophysics Data System (ADS)

    Apolinário, João; Fernandes, Rui; Bos, Machiel

    2014-05-01

    Fernandes et al. (2013) estimated the angular velocity of the Victoria tectonic block from geodetic data (GNSS derived velocities) only.. GNSS observations are sparse in this region and it is therefore of the utmost importance to use the available data (5 sites) in the most optimal way. Unfortunately, the existing time-series were/are affected by missing data and offsets. In addition, some time-series were close to the considered minimal threshold value to compute one reliable velocity solution: 2.5-3.0 years. In this research, we focus on the sensitivity of the derived angular velocity to changes in the data (longer data-span for some stations) by extending the used data-span: Fernandes et al. (2013) used data until September 2011. We also investigate the effect of adding other stations to the solution, which is now possible since more stations became available in the region. In addition, we study if the conventional power-law plus white noise model is indeed the best stochastic model. In this respect, we apply different noise models using HECTOR (Bos et al. (2013), which can use different noise models and estimate offsets and seasonal signals simultaneously. The seasonal signal estimation is also other important parameter, since the time-series are rather short or have large data spans at some stations, which implies that the seasonal signals still can have some effect on the estimated trends as shown by Blewitt and Lavellee (2002) and Bos et al. (2010). We also quantify the magnitude of such differences in the estimation of the secular velocity and their effect in the derived angular velocity. Concerning the offsets, we investigate how they can, detected and undetected, influence the estimated plate motion. The time of offsets has been determined by visual inspection of the time-series. The influence of undetected offsets has been done by adding small synthetic random walk signals that are too small to be detected visually but might have an effect on the

  12. Analysis of the water balance of Lake Victoria

    NASA Astrophysics Data System (ADS)

    Nossent, J.; de Brabanter, W.; Bauwens, W.

    2009-04-01

    Lake Victoria is situated within an elevated plateau in the western part of Africa's Great Rift Valley and lies within the territory of three countries: Tanzania, Uganda and Kenya. It is Africa's largest lake and the second widest fresh water lake in the world in terms of surface area. It is also the source of the longest branch of the River Nile, the White Nile. The lake's shallowness, limited river inflow, and large surface area relative to its volume make it vulnerable to climate changes and fluctuations of the water level. This affects the surrounding countries and their people a lot, especially in terms of their food supply and economy. The aim of this study was to get more information on the causes of these fluctuations by analysing the water balance of the lake for the period 1970-1974. It was based both on historical data and measurements and new calculations, and compared with previous studies (e.g. Suttcliffe and Parks, 1999). Precipitation and evaporation over the lake surface were calculated with the Thiessen Polygons method, using measurements from stations around the lake and on the islands. The total inflow of the lake is the sum of the contributions of twelve subbasins. One of these subcatchments, the Nzoia-catchment, was modeled with SWAT (Soil and Water Assessment Tool), a physically based, semi-distributed river basin simulator, as a contribution to the development of a water balance model for Lake Victoria. To calculate the outflow at the Owen Falls Dam in Jinja (Uganda), gauge heights of the lake were used in combination with the "Agreed Curve" (the relationship between water level and flow that was set by the policy makers). As the lake is assumed to be a system with a closed mass balance, the combination of the variations in the above mentioned components resulted in changes of the lake's storage, leading to fluctuations of the water level. For the period 1970-1974 the calculated mean monthly evaporation is 133 mm, with a standard deviation

  13. Trends and disparities in sepsis hospitalisations in Victoria, Australia.

    PubMed

    Ore, Timothy

    2015-12-14

    Objective The aim of the present study was to determine the clinical and epidemiological characteristics of patients with sepsis admitted to hospitals in Victoria, Australia, during the period 2004-14. The data include incidence, severity and mortality.Methods In all, 44 222 sepsis hospitalisations were identified between 2004-05 and 2013-14 from the Victorian Admitted Episodes Dataset. The dataset contains clinical and demographic information on all admissions to acute public and private hospitals. Using the International Classification of Diseases (10th Revision) Australian Modification codes, incidence rates, severity of disease and mortality were calculated.Results Sepsis hospitalisation rates per 10 000 population increased significantly (P < 0.01) over the period, from 6.9 (95% confidence interval (CI) 5.6-7.8) to 10.0 (95% CI 9.1-11.1), an annual growth rate of 3.8%. The age-standardised in-hospital death rates per 100 000 population grew significantly (P < 0.01) from 9.2 (95% CI 7.8-10.4) in 2004-05 to 13.0 (95% CI 11.7-14.6) in 2013-14, an annual growth rate of 3.1%. Among people under 45 years of age, the 0-4 years age group had the highest hospitalisation rate (3.0 per 10 000 population; 95% CI 2.7-3.4). Nearly half (46.2%) of all sepsis hospitalisations were among patients born overseas, with a rate of 14.5 per 10 000 population (95% CI 12.4-16.2) in that group compared with a rate of 5.9 per 10 000 population (95% CI 5.3-6.7) for patients born in Australia. The age-standardised sepsis hospitalisation rate was 2.6-fold greater in the lowest compared with highest socioeconomic areas (12.7 per 10 000 population (95% CI 11.2-13.8) vs 4.8 per 10 000 population (95% CI 4.1-5.7), respectively).Conclusion This paper shows a significant upward trend in both sepsis separation rates and in-hospital death rates over the period; unlike sepsis, in-hospital death rates from all diagnoses fell over the same period. The results can be used to stimulate review of

  14. Cubozoan jellyfish: an Evo/Devo model for eyes and other sensory systems.

    PubMed

    Piatigorsky, Joram; Kozmik, Zbynek

    2004-01-01

    Cnidaria are the most basal phylum containing a well-developed visual system located on specialized sensory structures (rhopalia) with eyes and statocyts. We have been exploring the cubozoan jellyfish, Tripedalia cystophora. In addition to containing simple photoreceptive ocelli, each rhopalium in Tridedalia has a large and small complex, camera-type eye with a cellular lens containing three distinct families of crystallins which apparently serve non-lenticular functions. Thus, Tridpedalia recruited crystallins by a gene sharing strategy as have mollusks and vertebrates. Tripedalia has a single Pax gene, PaxB, which encodes a structural and functional Pax 2/5/8-like paired domain as well as an octapeptide and Pax6-like homeodomain. PaxB binds to and activates Tripedalia crystallin promoters (especially J3-crystallin) and the Drosophila rhodopsin rh6 gene in transfection tests and induces ectopic eyes in Drosophila. In situ hybridization showed that PaxB and crystallin genes are expressed in the lens, retina and statocysts. We suggest from these results that an ancestral PaxB gene was a primordial gene in eye evolution and that eyes and ears (mechanoreceptors) may have had a common evolutionary origin. Thus, the numerous structural and molecular features of Tridpalia rhopalia indicate that ancient cubozoan jellyfish are fascinating models for evo/devo insights into eyes and other sensory systems.

  15. Investigation into the hemolytic activity of tentacle venom from jellyfish Cyanea nozakii Kishinouye

    NASA Astrophysics Data System (ADS)

    Li, Cuiping; Yu, Huahua; Li, Rongfeng; Xing, Ronge; Liu, Song; Li, Pengcheng

    2016-03-01

    Cyanea nozakii Kishinouy e ( C. nozakii), a giant cnidarian of the class Scyphomedusae, order Semaeostomeae and family Cyaneidae, is widely distributed in the East China Sea, the Yellow Sea and the Bohai Sea, and is abundant from late summer to early autumn. Venom produced by C. nozakii during mass agglomerations can contaminate seawater resulting in death of the halobios and seriously damage commercial fisheries. Swimmers and fishermen commonly suff er painful stings from this jellyfish, resulting in local edema, tingling, breathing difficulties, depressed blood pressure and even death. Such effects arise from the complex mixture of biologically active molecules that make up jellyfish venom. In the present study, the hemolytic activity of venom from tentacles of C. nozakii and factors aff ecting its activity were assayed. The HU50 ( defined as the amount of protein required to lyse 50 % of erythrocytes) of the venom against dove and chicken erythrocytes was 34 and 59 μg/mL, respectively. Carboxylmethyl chitosan and glycerol could increase hemolytic activity at concentrations greater than 0.06% and 0.2 mol/L, respectively.

  16. Morphology controlling method for amorphous silica nanoparticles and jellyfish-like nanowires and their luminescence properties

    PubMed Central

    Liu, Haitao; Huang, Zhaohui; Huang, Juntong; Xu, Song; Fang, Minghao; Liu, Yan-gai; Wu, Xiaowen; Zhang, Shaowei

    2016-01-01

    Uniform silica nanoparticles and jellyfish-like nanowires were synthesized by a chemical vapour deposition method on Si substrates treated without and with Ni(NO3)2, using silicon powder as the source material. Composition and structural characterization using field emission scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy and fourier-transform infrared spectroscopy showed that the as-prepared products were silica nanoparticles and nanowires which have amorphous structures. The form of nanoparticles should be related to gas-phase nucleation procedure. The growth of the nanowires was in accordance with vapour-liquid-solid mechanism, followed by Ostwald ripening to form the jellyfish-like morphology. Photoluminescence and cathodoluminescence measurements showed that the silica products excited by different light sources show different luminescence properties. The emission spectra of both silica nanoparticles and nanowires are due to the neutral oxygen vacancies (≡Si-Si≡). The as-synthesized silica with controlled morphology can find potential applications in future nanodevices with tailorable photoelectric properties. PMID:26940294

  17. Ecosystem engineers in the pelagic realm: alteration of habitat by species ranging from microbes to jellyfish.

    PubMed

    Breitburg, Denise L; Crump, Byron C; Dabiri, John O; Gallegos, Charles L

    2010-08-01

    Ecosystem engineers are species that alter the physical environment in ways that create new habitat or change the suitability of existing habitats for themselves or other organisms. In marine systems, much of the focus has been on species such as corals, oysters, and macrophytes that add physical structure to the environment, but organisms ranging from microbes to jellyfish and finfish that reside in the water column of oceans, estuaries, and coastal seas alter the chemical and physical environment both within the water column and on the benthos. By causing hypoxia, changing light regimes, and influencing physical mixing, these organisms may have as strong an effect as species that fall more clearly within the classical category of ecosystem engineer. In addition, planktonic species, such as jellyfish, may indirectly alter the physical environment through predator-mediated landscape structure. By creating spatial patterns of habitats that vary in their rates of mortality due to predation, planktonic predators may control spatial patterns and abundances of species that are the direct creators or modifiers of physical habitat.

  18. Morphology controlling method for amorphous silica nanoparticles and jellyfish-like nanowires and their luminescence properties

    NASA Astrophysics Data System (ADS)

    Liu, Haitao; Huang, Zhaohui; Huang, Juntong; Xu, Song; Fang, Minghao; Liu, Yan-Gai; Wu, Xiaowen; Zhang, Shaowei

    2016-03-01

    Uniform silica nanoparticles and jellyfish-like nanowires were synthesized by a chemical vapour deposition method on Si substrates treated without and with Ni(NO3)2, using silicon powder as the source material. Composition and structural characterization using field emission scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy and fourier-transform infrared spectroscopy showed that the as-prepared products were silica nanoparticles and nanowires which have amorphous structures. The form of nanoparticles should be related to gas-phase nucleation procedure. The growth of the nanowires was in accordance with vapour-liquid-solid mechanism, followed by Ostwald ripening to form the jellyfish-like morphology. Photoluminescence and cathodoluminescence measurements showed that the silica products excited by different light sources show different luminescence properties. The emission spectra of both silica nanoparticles and nanowires are due to the neutral oxygen vacancies (≡Si-Si≡). The as-synthesized silica with controlled morphology can find potential applications in future nanodevices with tailorable photoelectric properties.

  19. Jellyfish collagen and alginate: Combined marine materials for superior chondrogenesis of hMSC.

    PubMed

    Pustlauk, W; Paul, B; Gelinsky, M; Bernhardt, A

    2016-07-01

    Marine, hybrid constructs of porous scaffolds from fibrillized jellyfish collagen and alginate hydrogel are mimicking both of the main tissue components of cartilage, thus being a promising approach for chondrogenic differentiation of human mesenchymal stem cells (hMSC). Investigating their potential for articular cartilage repair, the present study examined scaffolds being either infiltrated with an alginate-cell-suspension (ACS) or seeded with hMSC and embedded in alginate after cell adhesion (EAS). Hybrid constructs with 2×10(5) and 4.5×10(5)hMSC/scaffold were compared to hMSC encapsulated in pure alginate discs, both chondrogenically stimulated for 21days. Typical round, chondrocyte-like morphology was observed in pure alginate gels and ACS scaffolds, while cells in EAS were elongated and tightly attached to the collagen pores. Col 2 gene expression was comparable in all scaffold types examined. However, the Col 2/Col 1 ratio was higher for pure alginate discs and ACS scaffolds compared to EAS. In contrast, cells in EAS scaffolds displayed higher gene expression of Sox 9, Col 11 and ACAN compared to ACS and pure alginate. Secretion of sulfated glycosaminoglycans (sGAG) was comparable for ACS and EAS scaffolds. In conclusion hybrid constructs of jellyfish collagen and alginate support hMSC chondrogenic differentiation and provide more stable and constructs compared to pure hydrogels.

  20. Structural and Developmental Disparity in the Tentacles of the Moon Jellyfish Aurelia sp.1.

    PubMed

    Gold, David A; Nakanishi, Nagayasu; Hensley, Nicholai M; Cozzolino, Kira; Tabatabaee, Mariam; Martin, Michelle; Hartenstein, Volker; Jacobs, David K

    2015-01-01

    Tentacles armed with stinging cells (cnidocytes) are a defining trait of the cnidarians, a phylum that includes sea anemones, corals, jellyfish, and hydras. While cnidarian tentacles are generally characterized as structures evolved for feeding and defense, significant variation exists between the tentacles of different species, and within the same species across different life stages and/or body regions. Such diversity suggests cryptic distinctions exist in tentacle function. In this paper, we use confocal and transmission electron microscopy to contrast the structure and development of tentacles in the moon jellyfish, Aurelia species 1. We show that polyp oral tentacles and medusa marginal tentacles display markedly different cellular and muscular architecture, as well as distinct patterns of cellular proliferation during growth. Many structural differences between these tentacle types may reflect biomechanical solutions to different feeding strategies, although further work would be required for a precise mechanistic understanding. However, differences in cell proliferation dynamics suggests that the two tentacle forms lack a conserved mechanism of development, challenging the textbook-notion that cnidarian tentacles can be homologized into a conserved bauplan.

  1. What do Victoria family physicians think about housecalls?

    PubMed Central

    Hammett, Tess

    2013-01-01

    Objective To determine the proportion of family physicians doing housecalls, the types of patients they think are appropriate to visit at home, whether physicians are satisfied with the number of housecalls they make, reasons family physicians list for not doing housecalls, and what they consider acceptable remuneration and travel time for housecalls. Design A 12-question paper survey was formulated specifically for this study and piloted by 6 family physicians in British Columbia. It was then mailed with a cover letter to 250 physicians' offices and faxed back anonymously. Setting Family physicians' private offices in Victoria, BC, between December 1 and 19, 2010. Participants A total of 250 randomly selected family physicians from a list of 552 physicians practising in Victoria on the College of Physicians and Surgeons of British Columbia website. Main outcome measures Proportion of physicians doing housecalls, reasons stated for not doing housecalls, and mean acceptable remuneration and travel time for a housecall. Results A total of 73 surveys (29.2%) were returned, 5 of which were not fully completed but were included for the questions that were answered. Sixty-four physicians (87.7%) did at least 1 housecall in the past year, 23 (31.5%) did housecalls at least once a month, and 12 (16.4%) did them at least once a week. Of 71 respondents, 64 physicians (90.1%) listed lack of time as a barrier to performing housecalls, 37 (52.1%) listed unsatisfactory remuneration, and 35 (49.3%) listed lengthy travel times. Most physicians indicated that appropriate remuneration for a housecall was either $142.21 (n = 30, 42.9%) or $108.41 (n = 26, 37.1%). Thirty-seven physicians (52.9%) noted that 20 minutes was an acceptable maximum 1-way travel time for a housecall, while 29 (41.4%) listed 10 minutes. Conclusion Several systemic factors, including lack of time, unsatisfactory remuneration, and large geographic catchment areas, make it difficult for urban family physicians

  2. Exploring the Antibacterial and Antifungal Potential of Jellyfish-Associated Marine Fungi by Cultivation-Dependent Approaches

    PubMed Central

    Yue, Yang; Yu, Huahua; Li, Rongfeng; Xing, Ronge; Liu, Song; Li, Pengcheng

    2015-01-01

    Fungi isolated from marine invertebrates are of considerable importance as new promising sources of unique secondary metabolites with significant biomedical potential. However, the cultivable fungal community harbored in jellyfish was less investigated. In this work, we seek to recover symbiotic fungi from different tissues of jellyfish Nemopilema nomurai. A total of seven morphotypes were isolated, which were assigned into four genera (Aspergillus, Cladosporium, Purpureocillium, and Tilletiopsis) from two phyla (Ascomycota and Basidiomycota) by comparing the rDNA-ITS sequences with the reference sequences in GenBank. The most fungi were found in the inner tissues of subumbrella. Two of the cultivation-independent procedures, changing media type and co-cultivation, were employed to maximize the complexity of metabolites. Thus, thirteen EtOAc gum were obtained and fingerprinted by High Performance Liquid Chromatography (HPLC) equipped with a photodiode array (PDA) detector. Antibacterial and antifungal activities of these complex mixtures were tested against a panel of bacterial and fungal pathogens. The antimicrobial results showed that all of the 13 EtOAc extracts displayed different levels of antibacterial activity, three of which exhibited strong to significant antibacterial activity to the bacterial pathogens Staphylococcus aureus and Salmonella entrica. Antifungal activity indicated that the EtOAc extracts from pure culture of Aspergillus versicolor and co-culture of A. versicolor and Tilletiopsis sp. in rice media were promising for searching new compounds, with the maximal mycelial growth inhibition of 82.32% ± 0.61% for Rhizoctonia solani and 48.41% ± 11.02% for Botrytis cinerea at 200 μg/ml, respectively. This study is the first report on the antibacterial and antifungal activity of jellyfish-associated fungi and allows the first sight into cultivable fungal community residing in jellyfish. Induced metabolites by cultivation-dependent approaches

  3. Exploring the Antibacterial and Antifungal Potential of Jellyfish-Associated Marine Fungi by Cultivation-Dependent Approaches.

    PubMed

    Yue, Yang; Yu, Huahua; Li, Rongfeng; Xing, Ronge; Liu, Song; Li, Pengcheng

    2015-01-01

    Fungi isolated from marine invertebrates are of considerable importance as new promising sources of unique secondary metabolites with significant biomedical potential. However, the cultivable fungal community harbored in jellyfish was less investigated. In this work, we seek to recover symbiotic fungi from different tissues of jellyfish Nemopilema nomurai. A total of seven morphotypes were isolated, which were assigned into four genera (Aspergillus, Cladosporium, Purpureocillium, and Tilletiopsis) from two phyla (Ascomycota and Basidiomycota) by comparing the rDNA-ITS sequences with the reference sequences in GenBank. The most fungi were found in the inner tissues of subumbrella. Two of the cultivation-independent procedures, changing media type and co-cultivation, were employed to maximize the complexity of metabolites. Thus, thirteen EtOAc gum were obtained and fingerprinted by High Performance Liquid Chromatography (HPLC) equipped with a photodiode array (PDA) detector. Antibacterial and antifungal activities of these complex mixtures were tested against a panel of bacterial and fungal pathogens. The antimicrobial results showed that all of the 13 EtOAc extracts displayed different levels of antibacterial activity, three of which exhibited strong to significant antibacterial activity to the bacterial pathogens Staphylococcus aureus and Salmonella entrica. Antifungal activity indicated that the EtOAc extracts from pure culture of Aspergillus versicolor and co-culture of A. versicolor and Tilletiopsis sp. in rice media were promising for searching new compounds, with the maximal mycelial growth inhibition of 82.32% ± 0.61% for Rhizoctonia solani and 48.41% ± 11.02% for Botrytis cinerea at 200 μg/ml, respectively. This study is the first report on the antibacterial and antifungal activity of jellyfish-associated fungi and allows the first sight into cultivable fungal community residing in jellyfish. Induced metabolites by cultivation-dependent approaches

  4. Victorias energy efficiency and cogeneration project. Final report

    SciTech Connect

    1998-10-31

    This report describes a two-phase energy project currently contemplated for joint implementation at the Victorias Milling Company, a large sugar mill and refinery on the island of Negros in the Visayas region of the Philippines. The Energy Efficiency (EE) phase is expected to reduce of eliminate VMC`s fossil fuel consumption, which will have a direct and substantial impact on carbon emissions. Phase I is an EE project which involves the installation of equipment to reduce steam and electricity demand in the factories. Phase II, will involve retrofitting and increasing the capacity of the steam and power generation systems, and selling power to the grid. By increasing efficiency and output, the cogeneration project will allow the factory to use only bagasse sugar cane fiber waste as fuel for energy needs. The cogeneration project will also eliminate VMC`s electricity purchases and supply additional power for the island, which will offset generation capacity expansion on the island and the Visayas region.

  5. Establishing a sustainable childhood obesity monitoring system in regional Victoria.

    PubMed

    Crooks, Nicholas; Strugnell, Claudia; Bell, Colin; Allender, Steve

    2016-12-19

    Issue addressed: Childhood obesity poses a significant immediate and long-term burden to individuals, societies and health systems. Infrequent and inadequate monitoring has led to uncertainty about trends in childhood obesity prevalence in many countries. High-quality data, collected at regular intervals, over extended timeframes, with high response rates and timely feedback are essential to support prevention efforts. Our aim was to establish a sustainable childhood obesity monitoring system in regional Australia to collect accurate anthropometric and behavioural data, provide timely feedback to communities and build community engagement and capacity.Methods: All schools from six government regions of South-West Victoria were invited to participate. Passive (opt-out) consent was used to collect measured anthropometric and self-reported behavioural data from children in years 2, 4, and 6, aged 7-12 years.Results: We achieved a 70% school participation rate (n=46) and a 93% student response rate (n=2198) among government and independent schools. Results were reported within 10 weeks post data collection. Harnessing high levels of community engagement throughout the planning, data collection and reporting phases increased community capacity and data utility.Conclusions: The monitoring system achieved high response rates, community engagement and community capacity building, and delivered results back to the community in a timely manner.So what?: This system has the potential to provide sustainable monitoring of childhood obesity that is not dependent on external funding. The results of this monitoring will likely inform health promotion efforts in communities across the region.

  6. Forty Meters from Entry to Victoria Crater (Stereo)

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA09972 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA09972

    NASA's Mars Exploration Rover Opportunity used its navigation camera during the rover's 1,278th Martian day, or sol, (Aug. 28, 2007) to take the images combined into this stereo view. The rover was perched at the lip of Victoria Crater, which is about 800 meters (one-half mile) in diameter.

    After assessment of possible routes for Opportunity to descend into the crater, the rover team selected a site farther to the right along the rim. That selected entry point lies near the ripple of bright soil visible just outside the crater near the top center of this scene. The driving distance for Opportunity from the Sol 1,278 viewpoint to the selected entry point is about 40 meters (about 130 feet).

    This view combines a stereo pair and appears three-dimensional when seen through blue-red glasses. It is presented as a cylindrical-perspective projection with geometric seam correction.

  7. Mandatory bicycle helmet use: experience in Victoria, Australia.

    PubMed

    Vulcan, A P; Cameron, M H; Watson, W L

    1992-01-01

    On July 1, 1990, the legislation requiring wearing of an approved bicycle (safety) helmet by all pedal cyclists, unless exempted, came into effect in Victoria, Australia. The paper describes the more important activities which paved the way for this initiative and presents some preliminary information about the effect of the legislation on wearing rates and head injuries. Since 1980 there has been promotion of helmet use through bicycle education in schools, mass media publicity, support by professional organizations and community groups, bulk purchase schemes, and government rebates for helmet purchases. The Australian Standard for bicycle safety helmets has also been changed to meet community demands for lighter helmets with more provision for ventilation. There has been a steady increase in voluntary helmet use in Melbourne from 1983 to March 1990, as follows: 5% to 70% in primary school children; 2% to 20% in secondary students; and 27% to 40% in adults. In the period after the legislation, with relatively little enforcement, these three groups have shown substantial increases in helmet use rates, rising to 70-90% in most cases. Preliminary data show that the numbers of bicyclists with a head injury have dropped in the period since the legislation came into effect. The possible contributions to this reduction, of less bicycle use and lower risk of head injury in an accident, are discussed.

  8. Stratigraphie relations of australites in the Port Campbell Embayment, Victoria

    USGS Publications Warehouse

    Shoemakeri, E.M.; Ralph, Uhlherr H.

    1999-01-01

    In the Port Campbell Embayment of Victoria, australites have been found in situ in channel deposits of the Hanson Plain Sand of Pliocene and Pleistocene age. The large majority of the australites, however, occur as a lag deposit at the basal contact of the Sturgess Sand of late Pleistocene and Holocene age and are spatially correlated with ferruginous sandstone clasts that are derived from the Hanson Plain Sand. Some of the tektites are imbedded in or bonded to the ferruginous sandstone clasts, but most are found as individual tektite fragments. A few percent of the tektites have nearly perfectly preserved, complete aerodynamically shaped forms. The sandstone clasts and associated tektites have been reworked from the much older underlying Hanson Plain and have been locally concentrated in the lag deposit. Some tektites also occur at higher levels in the Sturgess Sand, almost invariably in association with stone flakes, exotic stones transported by the aborigines and, locally, with middens of mollusc shells. Circumstantial evidence indicates that the aborigines transported the tektites found in the upper part of the Sturgess, particularly at Stanhope Bay. As Port Campbell australites unequivocally occur in strata much older than the late Pleistocene and Holocene Sturgess, there is no longer any conflict between the apparent stratigraphie age of the tektites and the middle Pleistocene ages obtained by various Chronometrie methods. ?? Meteoritical Society, 1999.

  9. Injuries associated with fireworks in Victoria: an epidemiological overview

    PubMed Central

    Abdulwadud, O.; Ozanne-Smith, J.

    1998-01-01

    Objectives—To determine the epidemiological features of injuries associated with fireworks. Design—A retrospective study of reported cases. Subjects—Subjects were those who attended selected Victorian hospital emergency departments (n=17) and those admitted for firework related injuries (n=16). Results—The mean (SD) age of attenders at emergency department between January 1988 and June 1996, was 8.9 (6.2) years and most (88%) were under 18 years of age. Males accounted for 71% of the cases. The most common anatomical sites and types of injury were head (47%) and burns (88%), respectively. About 53% of the injuries were caused by firecrackers, the remainder by sparklers and penny bangers. Among those admitted to hospital between July 1987 and June 1996, the mean (SD) age was 22.9 (14.8) years and 50% were under 18 years of age. Males accounted for 87% of the cases. There was a significant difference in mean age between those admitted and not admitted to hospital, the former being significantly older. Conclusions—Although relatively rare, injuries from fireworks still occur in Victoria after legislative restrictions on their sale in 1985. Consequently, there is a potential risk for injuries among children, particularly from firecrackers. More enforcement of the regulations, education, and parental supervision are needed to prevent injuries from fireworks. PMID:9887417

  10. Remote sensing water observation for supporting Lake Victoria weed management.

    PubMed

    Cavalli, Rosa Maria; Laneve, Giovanni; Fusilli, Lorenzo; Pignatti, Stefano; Santini, Federico

    2009-05-01

    This paper aims to assess the suitability of remote sensing for enhancing the management of water body resources and for providing an inexpensive way to gather, on a wide area, weed infestation extent and optical parameter linked to the water body status. Remotely sensed satellite images and ancillary ground true data were used to produce land cover maps, trough classification techniques, and water compounds maps, applying radiative transfer models. The study proposed within the framework of the cooperation between Italian Foreign Affair Ministry (through the University of Rome) and Kenyan Authorities has been carried out on the Kenyan part of the Lake Victoria. This lake is one of the largest freshwater bodies of the world where, over the last few years environmental challenges and human impact have perturbed the ecological balance affecting the biodiversity. The objective of this research study is to define the thematic products, retrievable from satellite images, like weed abundance maps and water compound concentrations. These products, if provided with an appropriate time frequency, are useful to identify the preconditions for the occurrence of hazard events like abnormal macrophyte proliferation and to develop an up-to-date decision support system devoted to an apprised territory, environment and resource management.

  11. Spectral analysis of storm surge in Hong Kong Victoria Harbour

    NASA Astrophysics Data System (ADS)

    Tou, Stephen K. W.; Arumugam, K.

    Based on a linear model the dynamic characteristics of Victoria Harbour (Hong Kong) is obtained by means of spectral analysis of the storm surge hydrographs. The results show that the harbour is an ideal one which has a small gain factor and a flat response in the frequency range from 0 to 6 × 10 -5 Hz. The results also show that the power spectra possess the narrow band features which indicates that the periodic components associated with tidal motions are predominant over the random components. The power spectrum corresponding to a frequency of 2.3 × 10 -5 Hz is likely to be associated with the astronomical tides. The peaks in the power spectra at zero frequency suggest that the pumping mode of oscillations is dominant in a storm surge. This mode of oscillations represents the temporal variations in mean sea level. To demonstrate the full potential of the present model, more case studies should be conducted when surge as well as non-surge data are available.

  12. Mossbauer study of sediment cores from Victoria harbour, Hong Kong

    PubMed

    Tanner; Leong; Pan; Yu

    2000-12-01

    The concentrations of Fe and other abundant metals in 6 m-long sediment cores from four locations in the world's largest container port, Hong Kong, have been determined, in addition to physical characteristics and 210Pb activities. Fe is generally present at concentrations between 2% and 3% (depending on the particle size), similar to values found in granitic rocks. Its speciation was studied by room temperature Mossbauer spectroscopy. Two Fe(II) species and one Fe(III) species were found to be present in the cores. The relative proportions of Fe(II) and Fe(III) generally changed with the depth of sediment. Most noticeably, for the core taken from near the Star Ferry Pier at the Kowloon side of Victoria harbour, the proportion of Fe(II) was fairly constant down to 4.75 m, but then decreased with depth, so that near the core base (6 m depth), the iron was present almost exclusively as Fe(III). The colour of the core changed from olive grey to olive yellow between 5 and 6 m. According to the core chronology, this depth represents ca. 1900, before the ferry pier construction, when the harbour was unpolluted.

  13. Management of glioblastoma in Victoria, Australia (2006-2008).

    PubMed

    Gan, Hui K; Rosenthal, Mark A; Cher, Lawrence; Dally, Michael; Drummond, Katharine; Murphy, Michael; Thursfield, Vicky

    2015-09-01

    We describe the management of patients with newly diagnosed glioblastoma multiforme (GBM) in a population-based cohort and compare this to a previously studied cohort. We performed a retrospective cohort study of patients diagnosed with GBM from 2006-2008 in Victoria, Australia. Patients were identified from the population-based Victorian Cancer Registry and their treating doctors surveyed by questionnaire. Outcomes were then compared to a study of GBM patients who were diagnosed between 1998 and 2000 using an identical methodology. We reviewed 351 eligible patients. There were slightly more males (62%) and a minority had multifocal disease (13%). Total macroscopic resection, partial resection or biopsy only was performed in 32%, 37% and 24% of patients, respectively. The majority of patients were referred to a radiation oncologist and medical oncologist postoperatively. A total of 56% of patients were treated with postoperative radiotherapy with concurrent and sequential temozolomide and had a median survival of 14.4 months. This was significantly better than patients treated with postoperative radiotherapy alone in the current or earlier cohorts (2006-2008: median survival 6.2 months, p<0.0001 versus 1998-2000: 8.9 months, p<0.0001). This study demonstrates that postoperative chemoradiation has become the standard of care in this Victorian population with an associated improvement in median survival.

  14. Diversity of soil yeasts isolated from South Victoria Land, Antarctica

    USGS Publications Warehouse

    Connell, L.; Redman, R.; Craig, S.; Scorzetti, G.; Iszard, M.; Rodriguez, R.

    2008-01-01

    Unicellular fungi, commonly referred to as yeasts, were found to be components of the culturable soil fungal population in Taylor Valley, Mt. Discovery, Wright Valley, and two mountain peaks of South Victoria Land, Antarctica. Samples were taken from sites spanning a diversity of soil habitats that were not directly associated with vertebrate activity. A large proportion of yeasts isolated in this study were basidiomycetous species (89%), of which 43% may represent undescribed species, demonstrating that culturable yeasts remain incompletely described in these polar desert soils. Cryptococcus species represented the most often isolated genus (33%) followed by Leucosporidium (22%). Principle component analysis and multiple linear regression using stepwise selection was used to model the relation between abiotic variables (principle component 1 and principle component 2 scores) and yeast biodiversity (the number of species present at a given site). These analyses identified soil pH and electrical conductivity as significant predictors of yeast biodiversity. Species-specific PCR primers were designed to rapidly discriminate among the Dioszegia and Leucosporidium species collected in this study. ?? 2008 Springer Science+Business Media, LLC.

  15. Global Transcriptome Analysis of the Tentacle of the Jellyfish Cyanea capillata Using Deep Sequencing and Expressed Sequence Tags: Insight into the Toxin- and Degenerative Disease-Related Transcripts

    PubMed Central

    Liu, Dan; Wang, Qianqian; Ruan, Zengliang; He, Qian; Zhang, Liming

    2015-01-01

    Background Jellyfish contain diverse toxins and other bioactive components. However, large-scale identification of novel toxins and bioactive components from jellyfish has been hampered by the low efficiency of traditional isolation and purification methods. Results We performed de novo transcriptome sequencing of the tentacle tissue of the jellyfish Cyanea capillata. A total of 51,304,108 reads were obtained and assembled into 50,536 unigenes. Of these, 21,357 unigenes had homologues in public databases, but the remaining unigenes had no significant matches due to the limited sequence information available and species-specific novel sequences. Functional annotation of the unigenes also revealed general gene expression profile characteristics in the tentacle of C. capillata. A primary goal of this study was to identify putative toxin transcripts. As expected, we screened many transcripts encoding proteins similar to several well-known toxin families including phospholipases, metalloproteases, serine proteases and serine protease inhibitors. In addition, some transcripts also resembled molecules with potential toxic activities, including cnidarian CfTX-like toxins with hemolytic activity, plancitoxin-1, venom toxin-like peptide-6, histamine-releasing factor, neprilysin, dipeptidyl peptidase 4, vascular endothelial growth factor A, angiotensin-converting enzyme-like and endothelin-converting enzyme 1-like proteins. Most of these molecules have not been previously reported in jellyfish. Interestingly, we also characterized a number of transcripts with similarities to proteins relevant to several degenerative diseases, including Huntington’s, Alzheimer’s and Parkinson’s diseases. This is the first description of degenerative disease-associated genes in jellyfish. Conclusion We obtained a well-categorized and annotated transcriptome of C. capillata tentacle that will be an important and valuable resource for further understanding of jellyfish at the molecular

  16. Long-term fluctuations in circalunar Beach aggregations of the box jellyfish Alatina moseri in Hawaii, with links to environmental variability.

    PubMed

    Chiaverano, Luciano M; Holland, Brenden S; Crow, Gerald L; Blair, Landy; Yanagihara, Angel A

    2013-01-01

    The box jellyfish Alatina moseri forms monthly aggregations at Waikiki Beach 8-12 days after each full moon, posing a recurrent hazard to swimmers due to painful stings. We present an analysis of long-term (14 years: Jan 1998- Dec 2011) changes in box jellyfish abundance at Waikiki Beach. We tested the relationship of beach counts to climate and biogeochemical variables over time in the North Pacific Sub-tropical Gyre (NPSG). Generalized Additive Models (GAM), Change-Point Analysis (CPA), and General Regression Models (GRM) were used to characterize patterns in box jellyfish arrival at Waikiki Beach 8-12 days following 173 consecutive full moons. Variation in box jellyfish abundance lacked seasonality, but exhibited dramatic differences among months and among years, and followed an oscillating pattern with significant periods of increase (1998-2001; 2006-2011) and decrease (2001-2006). Of three climatic and 12 biogeochemical variables examined, box jellyfish showed a strong, positive relationship with primary production, >2 mm zooplankton biomass, and the North Pacific Gyre Oscillation (NPGO) index. It is clear that that the moon cycle plays a key role in synchronizing timing of the arrival of Alatina moseri medusae to shore. We propose that bottom-up processes, likely initiated by inter-annual regional climatic fluctuations influence primary production, secondary production, and ultimately regulate food availability, and are therefore important in controlling the inter-annual changes in box jellyfish abundance observed at Waikiki Beach.

  17. Long-Term Fluctuations in Circalunar Beach Aggregations of the Box Jellyfish Alatina moseri in Hawaii, with Links to Environmental Variability

    PubMed Central

    Chiaverano, Luciano M.; Holland, Brenden S.; Crow, Gerald L.; Blair, Landy; Yanagihara, Angel A.

    2013-01-01

    The box jellyfish Alatina moseri forms monthly aggregations at Waikiki Beach 8–12 days after each full moon, posing a recurrent hazard to swimmers due to painful stings. We present an analysis of long-term (14 years: Jan 1998– Dec 2011) changes in box jellyfish abundance at Waikiki Beach. We tested the relationship of beach counts to climate and biogeochemical variables over time in the North Pacific Sub-tropical Gyre (NPSG). Generalized Additive Models (GAM), Change-Point Analysis (CPA), and General Regression Models (GRM) were used to characterize patterns in box jellyfish arrival at Waikiki Beach 8–12 days following 173 consecutive full moons. Variation in box jellyfish abundance lacked seasonality, but exhibited dramatic differences among months and among years, and followed an oscillating pattern with significant periods of increase (1998–2001; 2006–2011) and decrease (2001–2006). Of three climatic and 12 biogeochemical variables examined, box jellyfish showed a strong, positive relationship with primary production, >2 mm zooplankton biomass, and the North Pacific Gyre Oscillation (NPGO) index. It is clear that that the moon cycle plays a key role in synchronizing timing of the arrival of Alatina moseri medusae to shore. We propose that bottom-up processes, likely initiated by inter-annual regional climatic fluctuations influence primary production, secondary production, and ultimately regulate food availability, and are therefore important in controlling the inter-annual changes in box jellyfish abundance observed at Waikiki Beach. PMID:24194856

  18. Antioxidant activity of the giant jellyfish Nemopilema nomurai measured by the oxygen radical absorbance capacity and hydroxyl radical averting capacity methods.

    PubMed

    Harada, Kazuki; Maeda, Toshimichi; Hasegawa, Yoshiro; Tokunaga, Takushi; Ogawa, Shinya; Fukuda, Kyoko; Nagatsuka, Norie; Nagao, Keiko; Ueno, Shunshiro

    2011-01-01

    The giant jellyfish Nemopilema nomurai (reaching sizes of up to 2 m diameter and 150 kg), which forms dense blooms, has caused extensive damage to fisheries by overloading trawl nets, while its toxic nematocysts cause dermatological symptoms. Giant jellyfish are currently discarded on the grounds of pest control. However, the giant jellyfish is considered to be edible and is part of Chinese cuisine. Therefore, we investigated whether any benefits for human health may be derived from consumption of the jellyfish in order to formulate medicated diets. Antioxidant activity of Nemopilema nomurai was measured using the oxygen radical absorbance capacity (ORAC) and hydroxyl radical averting capacity (HORAC) methods. Based on the results, the ORAC value of the giant jellyfish freeze-dried sample was 541 µmol trolox equivalent (TE)/100 g and the HORAC value was 3,687 µmol gallic acid equivalent (GAE)/100 g. On the other hand, the IC50 value of hydroxyl radical scavenging activity measured by using the electron spin resonance method was 3.3%. In conclusion, the results suggest that the freeze-dried powder of the giant jellyfish Nemopilema nomurai is a potentially beneficial food for humans.

  19. Development of Plant Gene Vectors for Tissue-Specific Expression Using GFP as a Reporter Gene

    NASA Technical Reports Server (NTRS)

    Jackson, Jacquelyn; Egnin, Marceline; Xue, Qi-Han; Prakash, C. S.

    1997-01-01

    Reporter genes are widely employed in plant molecular biology research to analyze gene expression and to identify promoters. Gus (UidA) is currently the most popular reporter gene but its detection requires a destructive assay. The use of jellyfish green fluorescent protein (GFP) gene from Aequorea Victoria holds promise for noninvasive detection of in vivo gene expression. To study how various plant promoters are expressed in sweet potato (Ipomoea batatas), we are transcriptionally fusing the intron-modified (mGFP) or synthetic (modified for codon-usage) GFP coding regions to these promoters: double cauliflower mosaic virus 35S (CaMV 35S) with AMV translational enhancer, ubiquitin7-intron-ubiquitin coding region (ubi7-intron-UQ) and sporaminA. A few of these vectors have been constructed and introduced into E. coli DH5a and Agrobacterium tumefaciens EHA105. Transient expression studies are underway using protoplast-electroporation and particle bombardment of leaf tissues.

  20. Role of Coherent Low-Frequency Motion in Excited-State Proton Transfer of Green Fluorescent Protein Studied by Time-Resolved Impulsive Stimulated Raman Spectroscopy.

    PubMed

    Fujisawa, Tomotsumi; Kuramochi, Hikaru; Hosoi, Haruko; Takeuchi, Satoshi; Tahara, Tahei

    2016-03-30

    Green fluorescent protein (GFP) from jellyfish Aequorea victoria, an essential bioimaging tool, luminesces via excited-state proton transfer (ESPT) in which the phenolic proton of the p-hydroxybenzylideneimidazolinone chromophore is transferred to Glu222 through a hydrogen-bond network. In this process, the ESPT mediated by the low-frequency motion of the chromophore has been proposed. We address this issue using femtosecond time-resolved impulsive stimulated Raman spectroscopy. After coherently exciting low-frequency modes (<300 cm(-1)) in the excited state of GFP, we examined the excited-state structural evolution and the ESPT dynamics within the dephasing time of the low-frequency vibration. A clear anharmonic vibrational coupling is found between one high-frequency mode of the chromophore (phenolic CH bend) and a low-frequency mode at ∼104 cm(-1). However, the data show that this low-frequency motion does not substantially affect the ESPT dynamics.

  1. The use of aequorin and its variants for Ca2+ measurements.

    PubMed

    Granatiero, Veronica; Patron, Maria; Tosatto, Anna; Merli, Giulia; Rizzuto, Rosario

    2014-01-01

    Ca(2+)-sensitive photoproteins are ideal agents for measuring the Ca(2+) concentration ([Ca(2+)]) in intracellular organelles because they can be modified to include specific targeting sequences. Aequorin was the first Ca(2+)-sensitive photoprotein probe used to measure the [Ca(2+)] inside specific intracellular organelles in intact cells. Aequorin is a 22-kDa protein produced by the jellyfish Aequorea victoria. On the binding of Ca(2+) to three high-affinity sites in aequorin, an irreversible reaction occurs in which the prosthetic group is released and a photon is emitted. Aequorin has become widely used for intracellular Ca(2+) measurements because it offers many advantages: For example, it can be targeted with precision, functions over a wide range of [Ca(2+)], and shows low buffering capacity. In this article we describe the main characteristics of the aequorin probe and review the reasons why it is widely used to measure intracellular [Ca(2+)].

  2. Assessment of space environmental factors by cytotoxicity bioassays

    NASA Astrophysics Data System (ADS)

    Hellweg, Christine E.; Arenz, Andrea; Baumstark-Khan, Christa

    2007-02-01

    Cellular bioassays for detection of cyto- and genotoxicity are useful in the risk assessment of space environmental factors. Such bioassay systems have the potential complement the physical detector systems used in space, insofar as they yield intrinsically biologically weighted measures of cellular responses. The experiment Cellular Responses to Radiation in Space (CERASP) has been selected by NASA/ESA to be performed on the International Space Station. It will supply basic information on the cellular response to radiation applied in microgravity. One of the biological endpoints under investigation will be survival reflected by radiation-dependent reduction of constitutive expression of the enhanced variant of green fluorescent protein (EGFP), originally isolated from the bioluminescent jellyfish Aequorea victoria. In this ground based study, the usefulness of this approach in comparison to standard techniques (colony forming ability test, MTT test) is shown.

  3. Protein cyclization enhanced thermostability and exopeptidase-resistance of green fluorescent protein.

    PubMed

    Zhao, Zhonglin; Ma, Xin; Li, Liang; Zhang, Wei; Ping, Shuzhen; Xu, Ming-Qun; Lin, Min

    2010-03-01

    A mutant of green fluorescent protein (GFPmut3*) from the jellyfish Aequorea victoria was cyclized in vitro and in vivo by the use of a naturally split intein from the dnaE gene of Synechocystis species PCC6803 (Ssp). Cyclization of GFPmut3* was confirmed by amino acid sequencing and resulted in an increased electrophoretic mobility compared with the linear GFPmut3*. The circular GFPmut3* was 5 degrees C more thermostable than the linear form and significantly more resistant to proteolysis of exopeptidase. The circular GFPmut3* also displayed increased relative fluorescence intensity. In addition, chemical stability of GFPmut3* against GdnHCl revealed more stability of the circular form compared with the linear form.

  4. Fluorescence imaging in the last two decades.

    PubMed

    Miyawaki, Atsushi

    2013-02-01

    In commemoration of the 20th anniversary of the molecular cloning of the gene for the green fluorescent protein from the jellyfish Aequorea victoria, I would like to reflect on the development of new fluorescence imaging technology in the last two decades. As this technology has become increasingly diversified, it has become more and more of a challenge to come up with a comprehensive and exhaustive review of it. Here I will focus on optogenetics and large-scale, three-dimensional reconstruction. Those two technological innovations have been achieved in the neuroscience community owing to the combined efforts of molecular biologists and light microscopists. In addition, modern fluorescence imaging has indeed improved our understanding of the spatiotemporal regulation of fundamental biological functions at cellular level. As an example, I will introduce some findings we made regarding the movement of biomolecules across the nuclear membrane. The above-mentioned imaging approaches are possible today but were impossible two decades ago.

  5. Optical studies of dynamical processes in fluorescent proteins

    NASA Astrophysics Data System (ADS)

    Liebig, Carl; Dennis, William; Kirkpatrick, Sean; Naik, Rajesh; Stone, Morley

    2002-03-01

    Green fluorescent protein (GFP) extracted from the bioluminescent jellyfish Aequorea Victoria[1] and its mutants are novel nanoscale systems, which have been shown to exhibit desirable linear and nonlinear optical properties[2]. In this paper, a combination of both linear and nonlinear optical spectroscopic techniques was used to investigate dynamical processes in fluorescent proteins in both aqueous solution and an organic polymer matrix. Experimental results were analyzed in terms of a Brownian oscillator model[3] and by comparison to computer simulations. [1] M. Chalfie, G. Euskirchen, W. W. Ward and D. C. Prasher, Science 263 (1994) 802. [2] Sean M. Kirkpatrick, Rajesh R. Naik, Morley O. Stone, J. Phys. Chem. B 105 (2001) 2867. [3] S. Mukamel, "Nonlinear Optical Spectroscopy", (Oxford University Press, New York, 1995) pp. 227.

  6. Subcellular Localization of GUS- and GFP-Tagged Proteins in Onion Epidermal Cells.

    PubMed

    von Arnim, Albrecht

    2007-02-01

    INTRODUCTIONRecombinant tags (i.e., reporter proteins) offer an excellent alternative to antibodies for determining the subcellular localization of proteins. The most user-friendly tags are the ß-glucuronidase (GUS) reporter enzyme from Escherichia coli and fluorescent proteins derived primarily from the green fluorescent protein (GFP) of the jellyfish Aequorea victoria. GUS is useful primarily as a tag to address nuclear localization, whereas GFP is more versatile. Moreover, GFP is detectable directly in living cells, whereas GUS is only detected indirectly by staining of fixed tissue. This may lead to artifacts or it may obscure problems with protein solubility. In this protocol, protein localization is routinely assayed after particle-mediated transient transformation of onion epidermal cells. With this method it can be determined rapidly whether a given fusion protein is active, and preliminary targeting data can be obtained.

  7. [Construction and characterization of TetR and GFP fusion protein].

    PubMed

    Zuo, Yan; Yang, Ke-Qian

    2005-01-01

    Tetracycline repressor gene (tetR) from E. coli transposon Tn10 was fused in frame with green fluorescent protein gene (gfp) from jellyfish Aequorea Victoria on an E. coli expression vector and the fusion protein (TR::GFP) was purified. The binding of TR::GFP with tetracycline (tc) was demonstrated by nitrocellulose filter binding assay. TR::GFP also maintained the fluorescence property of GFP. Most significantly, fluorescence emission intensity of TR::GFP increased by 2-fold in the presence of tc, from 1.132 to 2.214, while those of GFP and TetR showed little change under similar conditions. The results indicated TR::GFP possesses characteristics of a tetracycline biosensor.

  8. Impact of cruise ship emissions in Victoria, BC, Canada

    NASA Astrophysics Data System (ADS)

    Poplawski, Karla; Setton, Eleanor; McEwen, Bryan; Hrebenyk, Dan; Graham, Mark; Keller, Peter

    2011-02-01

    Characterization of the effects of cruise ship emissions on local air quality is scarce. Our objective was to investigate community level concentrations of fine particulate matter (PM 2.5), nitrogen dioxide (NO 2) and sulphur dioxide (SO 2) associated with cruise ships in James Bay, Victoria, British Columbia (BC), Canada. Data obtained over four years (2005-2008) at the nearest air quality network site located 3.5 km from the study area, a CALPUFF modeling exercise (2007), and continuous measurements taken in the James Bay community over a three-month period during the 2009 cruise ship season were examined. Concentrations of PM 2.5 and nitrogen oxide (NO) were elevated on weekends with ships present with winds from the direction of the terminal to the monitoring station. SO 2 displayed the greatest impact from the presence of cruise ships in the area. Network data showed peaks in hourly SO 2 when ships were in port during all years. The CALPUFF modeling analysis found predicted 24-hour SO 2 levels to exceed World Health Organization (WHO) guidelines of 20 μg m -3 for approximately 3% of 24-hour periods, with a maximum 24-hour concentration in the community of 41 μg m -3; however, the CALPUFF model underestimated concentrations when predicted and measured concentrations were compared at the network site. Continuous monitoring at the location in the community predicted to experience highest SO 2 concentrations measured a maximum 24-hour concentration of 122 μg m -3 and 16% of 24-hour periods were above the WHO standard. The 10-minute concentrations of SO 2 reached up to 599 μg m -3 and exceeded the WHO 10-minute SO 2 guideline (500 μg m -3) for 0.03% of 10-minute periods. No exceedences of BC Provincial or Canadian guidelines or standards were observed.

  9. Evaluation of vehicle side airbag effectiveness in Victoria, Australia.

    PubMed

    D'Elia, Angelo; Newstead, Stuart; Scully, Jim

    2013-05-01

    Side airbag systems were first introduced into vehicles around 1995 to help protect occupants from injury in side impact crashes. International studies have shown that side airbags are effective in reducing the risk of death and injury, however, serious injuries can still occur even when side airbags deploy. The objective of this study was to use detailed injury information from insurance injury compensation claims data linked to Police reported crash data to determine the effectiveness of side airbags in reducing the risk of death or injury for occupants involved in side impact crashes in Victoria, Australia based on the specific body regions that side airbag systems are designed to protect. It was found that head and torso-protecting dual airbag systems designed to protect the head, neck, face, chest and abdomen are highly effective in reducing driver death or injury due to near side crashes. They were associated with a statistically significant reduction of 41.1% (25.9%, 53.2%) in the odds of death or injury across all body regions; and a 48.0% (28.0%, 62.4%) reduction in the odds of death or injury to the head, neck, face, chest and abdomen. The study did not find any evidence that torso-protecting airbags alone are effective in reducing death or injury. Analysis results indicate that head and torso-protecting side airbag systems in vehicles are a highly effective technology for reducing the risk of death or injury to vehicle occupants in near side crashes. The magnitude of the injury reduction benefits estimated indicate that fitment of this technology to all vehicles should be a high priority and will yield significant savings in overall road trauma.

  10. The Occurrence of Type S1A Serine Proteases in Sponge and Jellyfish

    NASA Technical Reports Server (NTRS)

    Rojas, Ana; Doolittle, Russell F.

    2003-01-01

    Although serine proteases are found in all kinds of cellular organisms and many viruses, the classic "chymotrypsin family" (Group S1A by th e 1998 Barrett nomenclature) has an unusual phylogenetic distribution , being especially common in animals, entirely absent from plants and protists, and rare among fungi. The distribution in Bacteria is larg ely restricted to the genus Streptomyces, although a few isolated occ urrences in other bacteria have been reported. The family may be enti rely absent from Archaea. Although more than a thousand sequences have been reported for enzymes of this type from animals, none of them ha ve been from early diverging phyla like Porifera or Cnidaria, We now report the existence of Group SlA serine proteases in a sponge (phylu m Porifera) and a jellyfish (phylum Cnidaria), making it safe to conc lude that all animal groups possess these enzymes.

  11. Effect of Venom from the Jellyfish Nemopilema nomurai on the Silkworm Bombyx mori L.

    PubMed

    Yu, Huahua; Li, Rongfeng; Chen, Xiaolin; Yue, Yang; Xing, Ronge; Liu, Song; Li, Pengcheng

    2015-09-24

    The silkworm Bombyx mori L. (B. mori) has a significant impact on the economy by producing more than 80% of the globally produced raw silk. The exposure of silkworm to pesticides may cause adverse effects on B. mori, such as a reduction in the production and quality of silk. This study aims to assay the effect of venom from the jellyfish Nemopilema nomurai on growth, cuticle and acetylcholinesterase (AChE) activity of the silkworm B. mori by the leaf dipping method. The experimental results revealed that the four samples caused neither antifeeding nor a lethal effect on B. mori. The sample SFV inhibited B. mori growth after 6 days of treatment in a dose-dependent manner. The samples SFV, DSFV and Fr-1 inhibited the precipitation and synthesis of chitin in the cuticle after 12 and 14 days of treatment. In the case of the four samples, the AChE was significantly improved after 14 days of treatment.

  12. Effect of Venom from the Jellyfish Nemopilema nomurai on the Silkworm Bombyx mori L

    PubMed Central

    Yu, Huahua; Li, Rongfeng; Chen, Xiaolin; Yue, Yang; Xing, Ronge; Liu, Song; Li, Pengcheng

    2015-01-01

    The silkworm Bombyx mori L. (B. mori) has a significant impact on the economy by producing more than 80% of the globally produced raw silk. The exposure of silkworm to pesticides may cause adverse effects on B. mori, such as a reduction in the production and quality of silk. This study aims to assay the effect of venom from the jellyfish Nemopilema nomurai on growth, cuticle and acetylcholinesterase (AChE) activity of the silkworm B. mori by the leaf dipping method. The experimental results revealed that the four samples caused neither antifeeding nor a lethal effect on B. mori. The sample SFV inhibited B. mori growth after 6 days of treatment in a dose-dependent manner. The samples SFV, DSFV and Fr-1 inhibited the precipitation and synthesis of chitin in the cuticle after 12 and 14 days of treatment. In the case of the four samples, the AChE was significantly improved after 14 days of treatment. PMID:26404374

  13. Exploring vortex enhancement and manipulation mechanisms in jellyfish that contributes to energetically efficient propulsion.

    PubMed

    Gemmell, Brad J; Costello, John H; Colin, Sean P

    2014-01-01

    The ability of animals to propel themselves efficiently through a fluid medium is ecologically advantageous. Flexible components that influence vortex interactions are widespread among animal propulsors. However the mechanisms by which vortices are enhanced and appropriately positioned for thrust generation are still poorly understood. Here, we describe how kinematic propulsor movements of a jellyfish can enhance and reposition a vortex ring that allows the recapture of wake energy for secondary thrust generation and efficient locomotion. We use high-speed video and digital particle image velocimetry (DPIV) to resolve kinematics simultaneously with fluid structures. These results provide new insight into how animals can manipulate fluid structures to reduce metabolic energy demands of swimming muscles and may have implications in bio-inspired design.

  14. Pelagia benovici sp. nov. (Cnidaria, Scyphozoa): a new jellyfish in the Mediterranean Sea.

    PubMed

    Piraino, Stefano; Aglieri, Giorgio; Martell, Luis; Mazzoldi, Carlotta; Melli, Valentina; Milisenda, Giacomo; Scorrano, Simonetta; Boero, Ferdinando

    2014-05-07

    A bloom of an unknown semaestome jellyfish species was recorded in the North Adriatic Sea from September 2013 to early 2014. Morphological analysis of several specimens showed distinct differences from other known semaestome species in the Mediterranean Sea and unquestionably identified them as belonging to a new pelagiid species within genus Pelagia. The new species is morphologically distinct from P. noctiluca, currently the only recognized valid species in the genus, and from other doubtful Pelagia species recorded from other areas of the world. Molecular analyses of mitochondrial cytochrome c oxidase subunit I (COI) and nuclear 28S ribosomal DNA genes corroborate its specific distinction from P. noctiluca and other pelagiid taxa, supporting the monophyly of Pelagiidae. Thus, we describe Pelagia benovici sp. nov. Piraino, Aglieri, Scorrano & Boero.

  15. Prokaryotic microbiota in the digestive cavity of the jellyfish Cotylorhiza tuberculata.

    PubMed

    Cortés-Lara, Sara; Urdiain, Mercedes; Mora-Ruiz, Merit; Prieto, Laura; Rosselló-Móra, Ramon

    2015-10-01

    The microbiota associated to the gastric cavity of four exemplars of the jellyfish Cotylorhiza tuberculata has been studied by means of cultured-dependent and -independent methods. The pyrosequencing approach rendered a very reduced diversity of Bacteria with four major groups shared by the four exemplars that made up to 95% of the total diversity. The culturing approach recovered low abundant organisms and some of them also detected by the pyrosequencing approach. The major key organisms were related to the genera Spiroplasma, Thalassospira, Tenacibaculum (from the pyrosequencing data), and Vibrio (from the cultivable fraction). Altogether the results indicate that C. tuberculata harbors an associated microbiota of very reduced diversity. On the other hand, some of the major key players may be potential pathogens and the host may serve as dispersal mechanism.

  16. Novel proteinaceous toxins from the box jellyfish (sea wasp) Carybdea rastoni.

    PubMed

    Nagai, H; Takuwa, K; Nakao, M; Ito, E; Miyake, M; Noda, M; Nakajima, T

    2000-08-28

    During summer and autumn, the box jellyfish (sea wasp) Carybdea rastoni is one of the most bothersome stinging pests to swimmers and bathers on the Japanese coast. Two labile but potent hemolytic toxins from the tentacles of Carybdea rastoni were isolated in their active forms using newly developed purification methods. The molecular masses of the isolated C. rastoni toxin-A and toxin-B (CrTX-A and CrTX-B) are 43 and 46 kDa, respectively, as calculated from SDS-PAGE. In the present study, we sequenced the full-length cDNA (1600 bp), which encodes both CrTX-A and CrTX-B. The deduced 450 amino acid sequence of the CrTXs, showed no significant homology with any known protein. This report presents the first complete sequence of a proteinaceous jellyfish toxin. Furthermore, it was revealed that CrTX-A was primarily localized in the nematocyst, whereas CrTX-B was detected only in the tentacle. Because the nematocyst is the organ responsible for the cnidarian sting, the remainder of the study focused on the toxicity of CrTX-A. We found that CrTX-A was fatally toxic to mice at 20 microg/kg (i.v.) and crayfish at 5 microg/kg (i.p.). Subcutaneously injected CrTX-A (0.1 microg) caused inflammation of mouse skin. These results showed that CrTX-A is responsible for the cutaneous inflammation observed in humans stung by C. rastoni.

  17. Cytotoxicity and hemolytic activity of jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae) venom.

    PubMed

    Kang, Changkeun; Munawir, Al; Cha, Mijin; Sohn, Eun-Tae; Lee, Hyunkyoung; Kim, Jong-Shu; Yoon, Won Duk; Lim, Donghyun; Kim, Euikyung

    2009-07-01

    The recent bloom of a giant jellyfish Nemopilema nomurai has caused a danger to sea bathers and fishery damages in the waters of China, Korea, and Japan. The present study investigated the cytotoxic and hemolytic activities of crude venom extract of N. nomurai using a number of in vitro assays. The jellyfish venom showed a much higher cytotoxic activity in H9C2 heart myoblast than in C2C12 skeletal myoblast (LC(50)=2 microg/mL vs. 12 microg/mL, respectively), suggesting its possible in vivo selective toxicity on cardiac tissue. This result is consistent with our previous finding that cardiovascular function is a target of the venom. In order to determine the stability of N. nomurai venom, its cytotoxicity was examined under the various temperature and pH conditions. The activity was relatively well retained at low environmental temperature (or=60 degrees C). In pH stability test, the venom has abruptly lost its activity at low pH environment (pH

  18. Jellyfish: the origin and distribution of extreme ram-pressure stripping events in massive galaxy clusters

    NASA Astrophysics Data System (ADS)

    McPartland, Conor; Ebeling, Harald; Roediger, Elke; Blumenthal, Kelly

    2016-01-01

    We investigate the observational signatures and physical origin of ram-pressure stripping (RPS) in 63 massive galaxy clusters at z = 0.3-0.7, based on images obtained with the Hubble Space Telescope. Using a training set of a dozen `jellyfish' galaxies identified earlier in the same imaging data, we define morphological criteria to select 211 additional, less obvious cases of RPS. Spectroscopic follow-up observations of 124 candidates so far confirmed 53 as cluster members. For the brightest and most favourably aligned systems, we visually derive estimates of the projected direction of motion based on the orientation of apparent compression shocks and debris trails. Our findings suggest that the onset of these events occurs primarily at large distances from the cluster core (>400 kpc), and that the trajectories of the affected galaxies feature high-impact parameters. Simple models show that such trajectories are highly improbable for galaxy infall along filaments but common for infall at high velocities, even after observational biases are accounted for, provided the duration of the resulting RPS events is ≲500 Myr. We thus tentatively conclude that extreme RPS events are preferentially triggered by cluster mergers, an interpretation that is supported by the disturbed dynamical state of many of the host clusters. This hypothesis implies that extreme RPS might occur also near the cores of merging poor clusters or even merging groups of galaxies. Finally, we present nine additional `jellyfish" galaxies at z > 0.3 discovered by us, thereby doubling the number of such systems known at intermediate redshift.

  19. Understanding virtual water flows: A multiregion input-output case study of Victoria

    NASA Astrophysics Data System (ADS)

    Lenzen, Manfred

    2009-09-01

    This article explains and interprets virtual water flows from the well-established perspective of input-output analysis. Using a case study of the Australian state of Victoria, it demonstrates that input-output analysis can enumerate virtual water flows without systematic and unknown truncation errors, an issue which has been largely absent from the virtual water literature. Whereas a simplified flow analysis from a producer perspective would portray Victoria as a net virtual water importer, enumerating the water embodiments across the full supply chain using input-output analysis shows Victoria as a significant net virtual water exporter. This study has succeeded in informing government policy in Australia, which is an encouraging sign that input-output analysis will be able to contribute much value to other national and international applications.

  20. Flow structure and transport characteristics of feeding and exchange currents generated by upside-down Cassiopea jellyfish.

    PubMed

    Santhanakrishnan, Arvind; Dollinger, Makani; Hamlet, Christina L; Colin, Sean P; Miller, Laura A

    2012-07-15

    Quantifying the flows generated by the pulsations of jellyfish bells is crucial for understanding the mechanics and efficiency of their swimming and feeding. Recent experimental and theoretical work has focused on the dynamics of vortices in the wakes of swimming jellyfish with relatively simple oral arms and tentacles. The significance of bell pulsations for generating feeding currents through elaborate oral arms and the consequences for particle capture are not as well understood. To isolate the generation of feeding currents from swimming, the pulsing kinematics and fluid flow around the benthic jellyfish Cassiopea spp. were investigated using a combination of videography, digital particle image velocimetry and direct numerical simulation. During the rapid contraction phase of the bell, fluid is pulled into a starting vortex ring that translates through the oral arms with peak velocities that can be of the order of 10 cm s(-1). Strong shear flows are also generated across the top of the oral arms throughout the entire pulse cycle. A coherent train of vortex rings is not observed, unlike in the case of swimming oblate medusae such as Aurelia aurita. The phase-averaged flow generated by bell pulsations is similar to a vertical jet, with induced flow velocities averaged over the cycle of the order of 1-10 mm s(-1). This introduces a strong near-horizontal entrainment of the fluid along the substrate and towards the oral arms. Continual flow along the substrate towards the jellyfish is reproduced by numerical simulations that model the oral arms as a porous Brinkman layer of finite thickness. This two-dimensional numerical model does not, however, capture the far-field flow above the medusa, suggesting that either the three-dimensionality or the complex structure of the oral arms helps to direct flow towards the central axis and up and away from the animal.

  1. Accumulation of nanoparticles in "jellyfish" mucus: a bio-inspired route to decontamination of nano-waste.

    PubMed

    Patwa, Amit; Thiéry, Alain; Lombard, Fabien; Lilley, Martin K S; Boisset, Claire; Bramard, Jean-François; Bottero, Jean-Yves; Barthélémy, Philippe

    2015-06-22

    The economic and societal impacts of nano-materials are enormous. However, releasing such materials in the environment could be detrimental to human health and the ecological biosphere. Here we demonstrate that gold and quantum dots nanoparticles bio-accumulate into mucus materials coming from natural species such as jellyfish. One strategy that emerges from this finding would be to take advantage of these trapping properties to remove nanoparticles from contaminated water.

  2. Stratigraphic architecture of bedrock reference section, Victoria Crater, Meridiani Planum, Mars

    USGS Publications Warehouse

    Edgar, Lauren A.; Grotzinger, John P.; Hayes, Alex G.; Rubin, David M.; Squyres, Steve W.; Bell, James F.; Herkenhoff, Ken E.

    2012-01-01

    The Mars Exploration Rover Opportunity has investigated bedrock outcrops exposed in several craters at Meridiani Planum, Mars, in an effort to better understand the role of surface processes in its geologic history. Opportunity has recently completed its observations of Victoria crater, which is 750 m in diameter and exposes cliffs up to ~15 m high. The plains surrounding Victoria crater are ~10 m higher in elevation than those surrounding the previously explored Endurance crater, indicating that the Victoria crater exposes a stratigraphically higher section than does the Endurance crater; however, Victoria strata overlap in elevation with the rocks exposed at the Erebus crater. Victoria crater has a well-developed geomorphic pattern of promontories and embayments that define the crater wall and that reveal thick bedsets (3–7m) of large-scale cross-bedding, interpreted as fossil eolian dunes. Opportunity was able to drive into the crater at Duck Bay, located on the western margin of Victoria crater. Data from the Microscopic Imager and Panoramic Camera reveal details about the structures, textures, and depositional and diagenetic events that influenced the Victoria bedrock. A lithostratigraphic subdivision of bedrock units was enabled by the presence of a light-toned band that lines much of the upper rim of the crater. In ascending order, three stratigraphic units are named Lyell, Smith, and Steno; Smith is the light-toned band. In the Reference Section exposed along the ingress path at Duck Bay, Smith is interpreted to represent a zone of diagenetic recrystallization; however, its upper contact also coincides with a primary erosional surface. Elsewhere in the crater the diagenetic band crosscuts the physical stratigraphy. Correlation with strata present at nearby promontory Cape Verde indicates that there is an erosional surface at the base of the cliff face that corresponds to the erosional contact below Steno. The erosional contact at the base of Cape Verde

  3. Monitoring the water balance of Lake Victoria, East Africa, from space

    NASA Astrophysics Data System (ADS)

    Swenson, Sean; Wahr, John

    2009-05-01

    SummaryUsing satellite gravimetric and altimetric data, we examine trends in water storage and lake levels of multiple lakes in the Great Rift Valley region of East Africa for the years 2003-2008. GRACE total water storage estimates reveal that water storage declined in much of East Africa, by as much as 60 {mm}/{year}, while altimetric data show that lake levels in some large lakes dropped by as much as 1-2 m. The largest declines occurred in Lake Victoria, the Earth's second largest freshwater body. Because the discharge from the outlet of Lake Victoria is used to generate hydroelectric power, the role of human management in the lake's decline has been questioned. By comparing catchment water storage trends to lake level trends, we confirm that climatic forcing explains only about 50decline. This analysis provides an independent means of assessing the relative impacts of climate and human management on the water balance of Lake Victoria that does not depend on observations of dam discharge, which may not be publically available. In the second part of the study, the individual components of the lake water balance are estimated. Satellite estimates of changes in lake level, precipitation, and evaporation are used with observed lake discharge to develop a parameterization for estimating subsurface inflows due to changes in groundwater storage estimated from satellite gravimetry. At seasonal timescales, this approach provides closure to Lake Victoria's water balance to within 17 {mm}/{month}. The third part of this study uses the water balance of a downstream water body, Lake Kyoga, to estimate the outflow from Lake Victoria remotely. Because Lake Kyoga is roughly 20 times smaller in area than Lake Victoria, its water balance is strongly influenced by inflow from Lake Victoria. Lake Kyoga has been shown to act as a linear reservoir, where its outflow is proportional to the height of the lake. This model can be used with satellite altimetric lake levels to estimate a

  4. Assessing Human Impacts on the Water Balance of Lake Victoria Using GRACE and Altimeters.

    NASA Astrophysics Data System (ADS)

    Swenson, S. C.; Wahr, J. M.

    2008-12-01

    GRACE has provided global estimates of vertically integrated water storage anomalies at monthly intervals with a useful spatial resolution of 300-500 km. Water levels of large lakes are now routinely monitored by satellite altimeters. By combining these datasets, it may be possible to separate the effects of climate and human management on lake levels. During the period 2002-2006, the levels of Lake Victoria dropped about two meters. Water storage changes of Lake Victoria and other large lakes in the East African Rift Valley are compared, and the relative impacts of climate and human management are shown to be of similar magnitude.

  5. Chemodenitrification in the cryoecosystem of Lake Vida, Victoria Valley, Antarctica.

    PubMed

    Ostrom, N E; Gandhi, H; Trubl, G; Murray, A E

    2016-11-01

    Lake Vida, in the Victoria Valley of East Antarctica, is frozen, yet harbors liquid brine (~20% salt, >6 times seawater) intercalated in the ice below 16 m. The brine has been isolated from the surface for several thousand years. The brine conditions (permanently dark, -13.4 °C, lack of O2 , and pH of 6.2) and geochemistry are highly unusual. For example, nitrous oxide (N2 O) is present at a concentration among the highest reported for an aquatic environment. Only a minor (17) O anomaly was observed in N2 O, indicating that this gas was predominantly formed in the lake. In contrast, the (17) O anomaly in nitrate (NO3-) in Lake Vida brine indicates that approximately half or more of the NO3- present is derived from atmospheric deposition. Lake Vida brine was incubated in the presence of (15) N-enriched substrates for 40 days. We did not detect microbial nitrification, dissimilatory reduction of NO3- to ammonium (NH4+), anaerobic ammonium oxidation, or denitrification of N2 O under the conditions tested. In the presence of (15) N-enriched nitrite (NO2-), both N2 and N2 O exhibited substantial (15) N enrichments; however, isotopic enrichment declined with time, which is unexpected. Additions of (15) N-NO2- alone and in the presence of HgCl2 and ZnCl2 to aged brine at -13 °C resulted in linear increases in the δ(15) N of N2 O with time. As HgCl2 and ZnCl2 are effective biocides, we interpret N2 O production in the aged brine to be the result of chemodenitrification. With this understanding, we interpret our results from the field incubations as the result of chemodenitrification stimulated by the addition of (15) N-enriched NO2- and ZnCl2 and determined rates of N2 O and N2 production of 4.11-41.18 and 0.55-1.75 nmol L(-1)  day(-1) , respectively. If these rates are representative of natural production, the current concentration of N2 O in Lake Vida could have been reached between 6 and 465 years. Thus, chemodenitrification alone is sufficient to explain the

  6. Modulation of jellyfish nematocyst discharges and management of human skin stings in Nemopilema nomurai and Carybdea mora.

    PubMed

    Pyo, Min-Jung; Lee, Hyunkyoung; Bae, Seong Kyong; Heo, Yunwi; Choudhary, Indu; Yoon, Won Duk; Kang, Changkeun; Kim, Euikyung

    2016-01-01

    Even though jellyfish sting is common today, its first aid guideline has never been clear enough in a scientific point of view and the use of vinegar appears to be not accepted in common throughout the world. In the present study, to develop rational first aid guidelines for the stings of Nemopilema nomurai (scyphozoa) and Carybdea mora (cubozoa), the modulatory effects of various kinds of rinsing solutions have been assessed on nematocyst discharge and human skin tests. Among the solutions tested, vinegar (4% acetic acid) immediately caused significant nematocyst discharge in N. nomurai but not in C. mora. On the other hand, ethanol (70%) notably stimulated nematocyst discharge in C. mora and relatively less in N. nomurai. Moreover, isopropanol, a widely used solvent in pharmaceutical products, caused extensive nematocyst discharges in both N. nomurai and C. mora. Whereas, seawater did not elicit any nematocyst discharge in both jellyfish species. In human skin test, the rinsing with seawater also ameliorated the stinging-associated symptoms (pain and redness) in C. mora as well as N. nomurai. From this study, seawater appears not to induce any nematocyst discharge and can be safely used as a first aid rinsing solution for the jellyfish stings.

  7. Firing the Sting: Chemically Induced Discharge of Cnidae Reveals Novel Proteins and Peptides from Box Jellyfish (Chironex fleckeri) Venom

    PubMed Central

    Jouiaei, Mahdokht; Casewell, Nicholas R.; Yanagihara, Angel A.; Nouwens, Amanda; Cribb, Bronwen W.; Whitehead, Darryl; Jackson, Timothy N. W.; Ali, Syed A.; Wagstaff, Simon C.; Koludarov, Ivan; Alewood, Paul; Hansen, Jay; Fry, Bryan G.

    2015-01-01

    Cnidarian venom research has lagged behind other toxinological fields due to technical difficulties in recovery of the complex venom from the microscopic nematocysts. Here we report a newly developed rapid, repeatable and cost effective technique of venom preparation, using ethanol to induce nematocyst discharge and to recover venom contents in one step. Our model species was the Australian box jellyfish (Chironex fleckeri), which has a notable impact on public health. By utilizing scanning electron microscopy and light microscopy, we examined nematocyst external morphology before and after ethanol treatment and verified nematocyst discharge. Further, to investigate nematocyst content or “venom” recovery, we utilized both top-down and bottom-up transcriptomics–proteomics approaches and compared the proteome profile of this new ethanol recovery based method to a previously reported high activity and recovery protocol, based upon density purified intact cnidae and pressure induced disruption. In addition to recovering previously characterized box jellyfish toxins, including CfTX-A/B and CfTX-1, we recovered putative metalloproteases and novel expression of a small serine protease inhibitor. This study not only reveals a much more complex toxin profile of Australian box jellyfish venom but also suggests that ethanol extraction method could augment future cnidarian venom proteomics research efforts. PMID:25793725

  8. Diversity, Phylogeny and Expression Patterns of Pou and Six Homeodomain Transcription Factors in Hydrozoan Jellyfish Craspedacusta sowerbyi

    PubMed Central

    Hroudova, Miluse; Vojta, Petr; Strnad, Hynek; Krejcik, Zdenek; Ridl, Jakub; Paces, Jan; Vlcek, Cestmir; Paces, Vaclav

    2012-01-01

    Formation of all metazoan bodies is controlled by a group of selector genes including homeobox genes, highly conserved across the entire animal kingdom. The homeobox genes from Pou and Six classes are key members of the regulation cascades determining development of sensory organs, nervous system, gonads and muscles. Besides using common bilaterian models, more attention has recently been targeted at the identification and characterization of these genes within the basal metazoan phyla. Cnidaria as a diploblastic sister group to bilateria with simple and yet specialized organs are suitable models for studies on the sensory organ origin and the associated role of homeobox genes. In this work, Pou and Six homeobox genes, together with a broad range of other sensory-specific transcription factors, were identified in the transcriptome of hydrozoan jellyfish Craspedacusta sowerbyi. Phylogenetic analyses of Pou and Six proteins revealed cnidarian-specific sequence motifs and contributed to the classification of individual factors. The majority of the Craspedacusta sowerbyi Pou and Six homeobox genes are predominantly expressed in statocysts, manubrium and nerve ring, the tissues with sensory and nervous activities. The described diversity and expression patterns of Pou and Six factors in hydrozoan jellyfish highlight their evolutionarily conserved functions. This study extends the knowledge of the cnidarian genome complexity and shows that the transcriptome of hydrozoan jellyfish is generally rich in homeodomain transcription factors employed in the regulation of sensory and nervous functions. PMID:22558464

  9. Impact assessment of non-indigenous jellyfish species on the estuarine community dynamic: A model of medusa phase

    NASA Astrophysics Data System (ADS)

    Muha, Teja Petra; Teodósio, Maria Alexandra; Ben-Hamadou, Radhouan

    2017-03-01

    Non-indigenous jellyfish species (NIJS) Blackforida virginica have recently been introduced to the Guadiana Estuary. A modelling approach was used for the assessment of the species-specific impact on the native community, during the medusa phase. The novel interactions between NIJS and the native community are assessed through biomass variation including hydrodynamic and climatic variables. Sensitivity analysis shows that both native species, as well as NIJS highly depend on the water discharge regime, nutrient contribution and the amount of detritus production. Abiotic factors such as the Northern Atlantic Oscillation, water discharge, nutrient load and detritus production are the most influential factors for the dynamics of the estuarine ecosystem demonstrated by the model. Low water discharge and low nutrient retention rate appear to be the most favourable conditions for B. virginica. The species is a non-selective predator able to integrate into the system effectively and has caused a decrease in the biomass of other organisms in the estuarine ecosystem throughout the summer after dam removal. The B. virginica significant impact can be evaluated only when the jellyfish detritus food pathway is involved. The B. virginica predatory impact potential, as well as food preference, appears to be the most influential factors for the overall biomass variation. On the contrary, winter freshwater pulses reduce the survival rate of jellyfish polyps which results in a decrease of medusa during summer. The model presents a strong ecohydrology movement where the fluctuation of organism biomass strongly depends on the hydrological conditions including the amount of nutrient load.

  10. [Lipid variation in oocytes of the jellyfish Stomolophus meleagris (Scyphozoa: Rhizostomeae) from Las Guasimas Lagoon, Mexico, during gonadal development].

    PubMed

    Carvalho-Saucedo, Liliana; García-Domínguez, Federico; Rodríguez-Jaramillo, Carmen; López-Martínez, Juana

    2010-03-01

    The jellyfish Stomolophus meleagris has potential for commercial exploitation but there is little information on their reproductive biology. This paper seeks to evaluate some biochemical and demographic characteristics of the species. Samples were taken monthly during 2005 and 2006. Jellyfish collected in 2005 were used to describe the characteristics and quantity of oocyte triglycerides and phospholipids with the Sudan black technique, and to ascertain the degree of gonadal development and sex ratio by the hematoxylin-eosin technique. The 2006 jellyfish were used to determine the size at first maturity and protein and total lipids contents. Four stages of development in both sexes were determined, with a continuous gamete development. The highest percentage of mature organisms was recorded in April. The proportion of sexes was 0.7:1.3. We found higher concentrations of triglycerides than phospholipids in the cytoplasm. There was a positive correlation between triglycerides and the diameter of the oocyte. The size at first maturity for both sexes was 105 mm. The highest protein and lipids contents were obtained in April and March respectively.

  11. Structural Analysis of the Victoria Quadrangle (H2) of Mercury based on NASA MESSENGER Data

    NASA Astrophysics Data System (ADS)

    Galluzzi, Valentina

    2015-04-01

    Objective of this thesis is the mapping and structural analysis of the H2 quadrangle, “Victoria”, and a reconnaissance study of the geometry and kinematics of lobate scarps on Mercury. To this end, I produced a 1:3,000,000 geologic map of the area using the images provided by the NASA spacecraft MESSENGER, which has been orbiting the planet since March, 2011. The geologic map shows the distribution of smooth plains, intermediate plains, intercrater plains units and a classification of crater materials based on an empirical distinction among three stages of degradation. Structural mapping shows that the H2 quadrangle is dominated by N-S faults (here grouped into the Victoria system) to the east and NE-SW faults (Larrocha system) to the west, with the secondary existence of NW-SE-trending faults (Carnegie system) in the north-western area of the quadrangle. A systematic analysis of these systems has led to the following results. 1) The Victoria system is characterized by a main array of faults located along Victoria Rupes - Endeavour Rupes - Antoniadi Dorsum. The segmentation of this array into three different sectors changes from north to south and is spatially linked to the presence of three volcanic vents located at the boundaries between each sector and at the northern end of the Victoria Rupes sector, suggesting that volcanism and faulting are interrelated. 2) The main array of Carnegie system is kinematically linked and antithetical to the Victoria system. Both systems have arguably controlled the growth of a longitudinal, fault-free, crustal and gravimetric bulge in the central area of the Victoria quadrangle, which is interpreted as a regional contractional pop-up. 3) The Larrocha system is interrupted against the central bulge and thus is probably older than the Victoria and Carnegie systems. Buffered crater counting performed on the Victoria system confirms the young relative age of its fault segments with respect to the map units. The faults of the

  12. Jellyfish collagen stimulates production of TNF-α and IL-6 by J774.1 cells through activation of NF-κB and JNK via TLR4 signaling pathway.

    PubMed

    Putra, Agus Budiawan Naro; Nishi, Kosuke; Shiraishi, Ryusuke; Doi, Mikiharu; Sugahara, Takuya

    2014-03-01

    We previously reported that jellyfish collagen stimulates both the acquired and innate immune responses. In the acquired immune response, jellyfish collagen enhanced immunoglobulin production by lymphocytes in vitro and in vivo. Meanwhile, in the innate immune response jellyfish collagen promoted cytokine production and phagocytotic activity of macrophages. The facts that jellyfish collagen plays several potential roles in stimulating cytokine production by macrophages have further attracted us to uncover its mechanisms. We herein describe that the cytokine production-stimulating activity of jellyfish collagen was canceled by a Toll-like receptor 4 (TLR4) inhibitor. Moreover, jellyfish collagen stimulated phosphorylation of inhibitor of κBα (IκBα), promoted the translocation of nucleus factor-κB (NF-κB), and activated c-Jun N-terminal kinase (JNK). A JNK inhibitor also abrogated the cytokine production-stimulating activity of jellyfish collagen. These results suggest that jellyfish collagen may facilitate cytokine production by macrophages through activation of NF-κB and JNK via the TLR4 signaling pathways.

  13. Jellyfish stings

    MedlinePlus

    ... of Medicine, University of Hawaii at Manoa, Honolulu, HI. Jacob L. Heller, MD, MHA, Emergency Medicine, Virginia ... A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the ...

  14. Plastic Jellyfish.

    ERIC Educational Resources Information Center

    Moseley, Christine

    2000-01-01

    Presents an environmental science activity designed to enhance students' awareness of the hazards of plastic waste for wildlife in aquatic environments. Discusses how students can take steps to reduce the effects of plastic waste. (WRM)

  15. Equity Indicators: Measures of Socio-Economic Status at Victoria University.

    ERIC Educational Resources Information Center

    Sinclair, Genevieve; Doughney, James; Palermo, Josephine

    After a review of relevant literature on socioeconomic status (SES) and the ways in which is used for higher education institutional research and policy, a detailed data analysis of Victoria University (VU), Australia student data was undertaken. Between 10,000 and 15,000 domestic student addresses were geocoded to Australian Bureau of Statistics…

  16. A Survey of People with Intellectual Disabilities Living in Residential Aged Care Facilities in Victoria

    ERIC Educational Resources Information Center

    Bigby, C.; Webber, R.; Bowers, B.; McKenzie-Green, B.

    2008-01-01

    Background: Australia's national ageing policy recognises that people ageing with intellectual disability (ID) require particular attention, yet there is no policy framework concerning this population. This study describes the distribution and characteristics of people with ID in residential aged care in Victoria, provides insights into the…

  17. The Killing of the Workers' Educational Association of Victoria: A Myth Challenged

    ERIC Educational Resources Information Center

    Dadswell, Gordon

    2004-01-01

    On 21 March 1941, the Council of the Workers' Educational Association of Victoria, Australia, (the Association) voted the organisation out of existence. The demise was in no way contemplated, and there was no practical reason why the Council acted in the way it did. This paper is the story of the destruction of a successful adult education…

  18. Connections '96. Proceedings of a Faculty Conference (2nd, Victoria, British Columbia, Canada, May 1996).

    ERIC Educational Resources Information Center

    Dayton-Sakari, Mary, Ed.; Miller, Carole S., Ed.; Liedtke, Werner, Ed.

    This proceedings contains 19 papers presented at the second annual faculty conference at the University of Victoria (British Columbia, Canada). Papers cover a wide variety of disciplines, including preschool education, classroom communication, mathematics instruction, theater, attention deficit disorders, distance learning by rural home schoolers,…

  19. Increase in Meningococcal Serogroup W Disease, Victoria, Australia, 2013–2015

    PubMed Central

    Stevens, Kerrie; Sohail, Asma; Franklin, Lucinda J.; Bond, Katherine A.; Brahmi, Aicha; Romanes, Finn; Ong, Katherine S.

    2016-01-01

    In Victoria, Australia, invasive meningococcal disease caused by Neisseria meningitidis serogroup W increased from 4% of all cases in 2013 to 30% in 2015. This increase resulted largely from strains similar to those in the serogroup W sequence type 11 clonal complex, previously described in the United Kingdom and South America. PMID:27648521

  20. Visy Cares Hub and Victoria University: Making the Door of a University Open to the Community

    ERIC Educational Resources Information Center

    Broadbent, Robyn

    2011-01-01

    In 1999, a group of men embarked on a remarkable project that resulted in building a two million dollar youth centre in one of Melbourne's most disadvantaged communities. From the outset, Victoria University (VU) was a keen partner in the project. This project had key synergies with the current experiences of the University--a dual sector higher…

  1. Perception of Aquaculture Education to Support Further Growth of Aquaculture Industry in Victoria, Australia

    ERIC Educational Resources Information Center

    Awal, Sadiqul; Christie, Andrew; Watson, Matthew; Hannadige, Asanka G. T.

    2012-01-01

    Purpose: The central aim of this study was to determine the perception of aquaculture educational provisions in the state of Victoria, and whether they are sufficient to ultimately support further growth of the industry. Design/methodology/approach: Questionnaires were formulated and distributed to participants in a variety of ways, including via…

  2. Employment Shifts in the TAFE Workforce in Victoria, 1993-98. Working Paper.

    ERIC Educational Resources Information Center

    Shah, Chandra

    Data on the work force in Technical and Further Education (TAFE) institutes in Victoria, Australia, for 1993-1998 reveal a number of structural changes. First, the number of women staff increased from 46% to 53%, although men still constitute 54% of the teaching staff. As full-time staff employment dropped an average of 1.1% annually, part-time…

  3. Vulnerability to Bushfires in Rural Australia: A Case Study from East Gippsland, Victoria

    ERIC Educational Resources Information Center

    Whittaker, Joshua; Handmer, John; Mercer, David

    2012-01-01

    This paper investigates the nature and causes of vulnerability to bushfires in the Wulgulmerang district of East Gippsland, Victoria, in south-eastern Australia. In 2003 bushfires devastated the small population of this isolated farming district, destroying homes, agricultural assets and public infrastructure. The fires also adversely affected the…

  4. History and timing of human impact on Lake Victoria, East Africa.

    PubMed Central

    Verschuren, Dirk; Johnson, Thomas C; Kling, Hedy J; Edgington, David N; Leavitt, Peter R; Brown, Erik T; Talbot, Michael R; Hecky, Robert E

    2002-01-01

    Lake Victoria, the largest tropical lake in the world, suffers from severe eutrophication and the probable extinction of up to half of its 500+ species of endemic cichlid fishes. The continuing degradation of Lake Victoria's ecological functions has serious long-term consequences for the ecosystem services it provides, and may threaten social welfare in the countries bordering its shores. Evaluation of recent ecological changes in the context of aquatic food-web alterations, catchment disturbance and natural ecosystem variability has been hampered by the scarcity of historical monitoring data. Here, we present high-resolution palaeolimnological data, which show that increases in phytoplankton production developed from the 1930s onwards, which parallels human-population growth and agricultural activity in the Lake Victoria drainage basin. Dominance of bloom-forming cyanobacteria since the late 1980s coincided with a relative decline in diatom growth, which can be attributed to the seasonal depletion of dissolved silica resulting from 50 years of enhanced diatom growth and burial. Eutrophication-induced loss of deep-water oxygen started in the early 1960s, and may have contributed to the 1980s collapse of indigenous fish stocks by eliminating suitable habitat for certain deep-water cichlids. Conservation of Lake Victoria as a functioning ecosystem is contingent upon large-scale implementation of improved land-use practices. PMID:11839198

  5. From Aspiration to Destination: Understanding the Decisions of University Applicants in Regional Victoria

    ERIC Educational Resources Information Center

    Harvey, Andrew; Burnheim, Catherine; Joschko, Lucie; Luckman, Michael

    2012-01-01

    This paper examines the choices and destinations of prospective university students from three regional areas in Victoria. The study is based on information collected for tertiary applicants in the Gippsland, Bendigo and Mildura areas, all of which host a local university campus. Using application and enrollment data, we examine the choices that…

  6. 75 FR 9114 - FM Table of Allotments, Markham, Ganado, and Victoria, Texas

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-01

    ... COMMISSION 47 CFR Part 73 FM Table of Allotments, Markham, Ganado, and Victoria, Texas AGENCY: Federal... counterproposal filed by Fort Bend Broadcasting Company, licensee of Station KHTZ(FM), Ganado, Texas, to upgrade Station KHTZ(FM) from Channel 284C2 to Channel 235C and to modify its license accordingly....

  7. History and timing of human impact on Lake Victoria, East Africa.

    PubMed

    Verschuren, Dirk; Johnson, Thomas C; Kling, Hedy J; Edgington, David N; Leavitt, Peter R; Brown, Erik T; Talbot, Michael R; Hecky, Robert E

    2002-02-07

    Lake Victoria, the largest tropical lake in the world, suffers from severe eutrophication and the probable extinction of up to half of its 500+ species of endemic cichlid fishes. The continuing degradation of Lake Victoria's ecological functions has serious long-term consequences for the ecosystem services it provides, and may threaten social welfare in the countries bordering its shores. Evaluation of recent ecological changes in the context of aquatic food-web alterations, catchment disturbance and natural ecosystem variability has been hampered by the scarcity of historical monitoring data. Here, we present high-resolution palaeolimnological data, which show that increases in phytoplankton production developed from the 1930s onwards, which parallels human-population growth and agricultural activity in the Lake Victoria drainage basin. Dominance of bloom-forming cyanobacteria since the late 1980s coincided with a relative decline in diatom growth, which can be attributed to the seasonal depletion of dissolved silica resulting from 50 years of enhanced diatom growth and burial. Eutrophication-induced loss of deep-water oxygen started in the early 1960s, and may have contributed to the 1980s collapse of indigenous fish stocks by eliminating suitable habitat for certain deep-water cichlids. Conservation of Lake Victoria as a functioning ecosystem is contingent upon large-scale implementation of improved land-use practices.

  8. Compatibility of Ugandan Schistosoma mansoni isolates with Biomphalaria snail species from Lake Albert and Lake Victoria.

    PubMed

    Adriko, Moses; Standley, Claire J; Tinkitina, Benjamin; Mwesigwa, Gerald; Kristensen, Thomas K; Stothard, J Russell; Kabatereine, Narcis B

    2013-11-01

    In order to investigate the capacity of being intermediate host for Schistosoma mansoni, the Ugandan F1 generation of Biomphalaria snail species that were laboratory-bred from parent populations originally collected from either Lake Victoria or Lake Albert was challenged with sympatric and non-sympatric S. mansoni isolates. After a prepatent period of 20 days, a daily 10-hourly snail shedding for cercariae was done to determine the infection rate, cercarial production per hour and survival period of infected snails. The study suggests that when parasite strains from a different geographical origin is used for infection, survival of infected snails increase, leading to an increased transmission potential. Although earlier literature had indicated that the Lake Victoria Biomphalaria sudanica is refractory to S. mansoni, we showed that all Ugandan Biomphalaria spp., including B. sudanica from all locations, were highly susceptible to the S. mansoni isolates. Thus if B. choanomphala, which is an efficient intermediate host in Lake Victoria, is given an opportunity to occupy Lake Albert, it will most likely be compatible with the Albertine S. mansoni parasites. Equally, if B. stanleyi, currently restricted to Lake Albert invades Lake Victoria, it is likely to act as an efficient intermediate host. Future work should concentrate on intraspecific population-level differences in compatibility.

  9. What Do the Public Search for on the Catalogue of the State Library of Victoria?

    ERIC Educational Resources Information Center

    Waller, Vivienne

    2009-01-01

    This study examines what the public search for in the catalogue of the State Library of Victoria (SLV). As well as indicating the type of content being accessed, this gives an indication of what catalogue users expect of the State Library collection. A content analysis was undertaken of a random, stratified sample of 4,000 search queries typed in…

  10. Establishing an Online Community of Inquiry at the Distance Education Centre, Victoria

    ERIC Educational Resources Information Center

    Jackson, Luke C.; Jackson, Alun C.; Chambers, Dianne

    2013-01-01

    This pilot intervention focused on three courses that were redesigned to utilize the online environment to establish an online community of inquiry (CoI). The setting for this research study was the Distance Education Centre, Victoria (DECV), an Australian co-educational school with approximately 3000 students who, for a variety of reasons, are…

  11. Connections '98. Proceedings of a Faculty Conference (4th, Victoria, British Columbia, Canada, May 1998).

    ERIC Educational Resources Information Center

    Gibbons, Sandra L., Ed.; Anderson, John O., Ed.

    This proceedings contains 13 papers from the 1998 annual Faculty of Education conference at the University of Victoria, British Columbia (Canada). The papers are: (1) "Struggling with Re-Presentation, Voice, and Self in Narrative Research" (Marla Arvay); (2) "Women's Soccer in Canada: A Slow Road to Equity" (Meredith Bogle,…

  12. Connections '99. Proceedings of a Faculty Conference (5th, Victoria, British Columbia, Canada, May 1999).

    ERIC Educational Resources Information Center

    Gibbons, Sandra L., Ed.; Liedtke, Werner W., Ed.

    This proceedings contains 13 papers from the 1999 annual conference of the Faculty of Education, University of Victoria (British Columbia). The papers are: (1) "Sacred and the Profane in Advertising Art" (Bill Zuk, Robert Dalton); (2) "Finding the Fund$ in Fun Run: Evaluating the Effectiveness and Efficiency of Physical Activity…

  13. Connections '97. Proceedings of a Faculty Conference (3rd, Victoria, British Columbia, Canada, May 1997).

    ERIC Educational Resources Information Center

    Liedtke, Werner, Ed.

    This proceedings contains 17 papers presented at the third annual faculty conference at the University of Victoria (British Columbia, Canada). Papers cover a wide variety of disciplines and topics, including student teaching, athletics, researcher-teacher collaboration, hands-on science instruction, violence prevention, youth violence, counseling,…

  14. Testing the Marine Hypothesis for The Opportunity Landing Site at Victoria Crater

    NASA Astrophysics Data System (ADS)

    Parker, T. J.

    2006-12-01

    Hypothesis Summary: 1. Meridiani Planum is a marine sulfate platform deposit, analogous to terrestrial carbonate platforms but with sulfate mineralogy, laid down during one or multiple marine transgressions over the landing site region. 2. Outcrop laminations, ripples, and larger, dune-scale bedforms are subaqueous in origin, produced by tidal currents. Aqueous deposits may be interbedded with crossbedded aeolian deposits of same composition derived from subjacent water-lain deposits during lowstands. At the scale of observations made by Opportunity, the marine hypothesis differs from the consensus, sabkha model, in two relatively minor ways (but with important differences in the inferred paleoenvironments). 3. Blueberry and cobble "lag" on top of outcrop is a lag, but indicates erosion of perhaps many meters, even tens of meters or more of outcrop material from the region by water. Wind erosion has been very limited over geologic time (perhaps less than a meter locally). 4. Remarkably-flat, horizontal geomorphic surface of outcrop was produced by shallow standing water locally, controlling both deposition and erosion of the sulfate outcrop material to within a few meters of sea level. 5. Craters in the landing site exhibit a continuum of degradation states, with Endurance and Victoria typifying the best preserved craters visited (or to be visited) by Opportunity, and Erebus and Terra Nova representing the most degraded craters visited that are larger than 100 meters across. Terra Nova is similar to numerous kilometer-scale "rock ring" craters in the Meridiani Planum landing site. 6. "Serrated" rim at Victoria is similar to, but fresher in expression, rim morphology at Erebus Crater, and may indicate water pouring over crater rim during tidal or storm surges in water level across the region. Predictions to be tested at Victoria Crater: 1. The crater's ejecta and raised rim have been destroyed by tidal currents in shallow standing water. There is no Endurance

  15. Pleistocene desiccation in East Africa bottlenecked but did not extirpate the adaptive radiation of Lake Victoria haplochromine cichlid fishes.

    PubMed

    Elmer, Kathryn R; Reggio, Chiara; Wirth, Thierry; Verheyen, Erik; Salzburger, Walter; Meyer, Axel

    2009-08-11

    The Great Lakes region of East Africa, including Lake Victoria, is the center of diversity of the mega-diverse cichlid fishes (Perciformes: Teleostei). Paleolimnological evidence indicates dramatic desiccation of this lake ca. 18,000-15,000 years ago. Consequently, the hundreds of extant endemic haplochromine species in the lake must have either evolved since then or refugia must have existed, within that lake basin or elsewhere, from which Lake Victoria was recolonized. We studied the population history of the Lake Victoria region superflock (LVRS) of haplochromine cichlids based on nuclear genetic analysis (12 microsatellite loci from 400 haplochomines) of populations from Lake Kivu, Lake Victoria, and the connected and surrounding rivers and lakes. Population genetic analyses confirmed that Lake Kivu haplochromines colonized Lake Victoria. Coalescent analyses show a 30- to 50-fold decline in the haplochromine populations of Lake Victoria, Lake Kivu, and the region ca. 18,000-15,000 years ago. We suggest that this coincides with drastic climatic and geological changes in the late Pleistocene. The most recent common ancestor of the Lake Victoria region haplochromines was estimated to have existed about 4.5 million years ago, which corresponds to the first radiation of cichlids in Lake Tanganyika and the origin of the tribe Haplochrominii. This relatively old evolutionary origin may explain the high levels of polymorphism still found in modern haplochromines. This degree of polymorphism might have acted as a "genetic reservoir" that permitted the explosive radiation of hundreds of haplochromines and their array of contemporary adaptive morphologies.

  16. Local versus Generalized Phenotypes in Two Sympatric Aurelia Species: Understanding Jellyfish Ecology Using Genetics and Morphometrics

    PubMed Central

    Chiaverano, Luciano M.; Bayha, Keith W.; Graham, William M.

    2016-01-01

    For individuals living in environmentally heterogeneous environments, a key component for adaptation and persistence is the extent of phenotypic differentiation in response to local environmental conditions. In order to determine the extent of environmentally induced morphological variation in a natural population distributed along environmental gradients, it is necessary to account for potential genetic differences contributing to morphological differentiation. In this study, we set out to quantify geographic morphological variation in the moon jellyfish Aurelia exposed at the extremes of a latitudinal environmental gradient in the Gulf of Mexico (GoM). We used morphological data based on 28 characters, and genetic data taken from mitochondrial cytochrome oxidase I (COI) and nuclear internal transcribed spacer 1 (ITS-1). Molecular analyses revealed the presence of two genetically distinct species of Aurelia co-occurring in the GoM: Aurelia sp. 9 and Aurelia c.f. sp. 2, named for its divergence from (for COI) and similarity to (for ITS-1) Aurelia sp. 2 (Brazil). Neither species exhibited significant population genetic structure between the Northern and the Southeastern Gulf of Mexico; however, they differed greatly in the degree of geographic morphological variation. The morphology of Aurelia sp. 9 exhibited ecophenotypic plasticity and varied significantly between locations, while morphology of Aurelia c.f. sp. 2 was geographically invariant (i.e., canalized). The plastic, generalist medusae of Aurelia sp. 9 are likely able to produce environmentally-induced, “optimal” phenotypes that confer high relative fitness in different environments. In contrast, the non-plastic generalist individuals of Aurelia c.f. sp. 2 likely produce environmentally-independent phenotypes that provide the highest fitness across environments. These findings suggest the two Aurelia lineages co-occurring in the GoM were likely exposed to different past environmental conditions (i

  17. Framework for Integrated Water, Energy, and Environmental Resources Assessment, Planning, and Management: Lake Victoria Case Study

    NASA Astrophysics Data System (ADS)

    Georgakakos, A.; Yao, H.; Tidwell, A.

    2006-12-01

    This article describes a recent assessment study for Lake Victoria in East Africa. The study includes three interlinked components. The first pertains to Lake Victoria regulation and includes climate and hydrologic forecasting (seasonal, inter-annual, and centennial), and outflow regulation (water resources planning). The second pertains to energy system planning, and the third to environmental and socio-economic impact assessments. These components converge at the operational level where water, energy, and environmental management are harmonized through the use of a decision support system, the Lake Victoria Decision Support Tool. Some of the broad study findings are summarized below: (1)Lake Victoria is entering a new era in which sustainable water resources management is tightly linked to and can only be achieved by proactive energy planning. To meet this new challenge, and maximize the benefit of the decision support system, water and energy sector decisions must be institutionally coordinated. (2)Climate and hydrologic forecasts of sufficient skill are critical for effective water resources and energy planning and management. More specifically, extensive assessments with several GCMs and climate scenarios indicate that Lake Victoria will most likely be adversely impacted by climate change with potentially serious local and regional consequences. Furthermore, seasonal and inter-annual forecasts are very important in meeting medium term water and energy demands and minimizing the costs of thermal energy generation. (3)Wetland ecological and socio-economic benefits are comparable to power sector benefits, underscoring the need for more comprehensive evaluations of non-power water uses and integrative water, energy, and environmental planning and management. (4)Integrated forecast-decision systems are excellent means to bring to bear and make practically available advances in various water-related disciplines for the benefit of managers and policy makers.

  18. Regional nitrogen budget of the Lake Victoria Basin, East Africa: syntheses, uncertainties and perspectives

    NASA Astrophysics Data System (ADS)

    Zhou, Minghua; Brandt, Patric; Pelster, David; Rufino, Mariana C.; Robinson, Timothy; Butterbach-Bahl, Klaus

    2014-10-01

    Using the net anthropogenic nitrogen input (NANI) approach we estimated the N budget for the Lake Victoria Basin in East Africa. The NANI of the basin ranged from 887 to 3008 kg N km-2 yr-1 (mean: 1827 kg N km-2 yr-1) for the period 1995-2000. The net nitrogen release at basin level is due primarily to livestock and human consumption of feed and foods, contributing between 69% and 85%. Atmospheric oxidized N deposition contributed approximately 14% to the NANI of the Lake Victoria Basin, while either synthetic N fertilizer imports or biological N fixations only contributed less than 6% to the regional NANI. Due to the low N imports of feed and food products (<20 kg N km-2 yr-1), nitrogen release to the watershed must be derived from the mining of soil N stocks. The fraction of riverine N export to Lake Victoria accounted for 16%, which is much lower than for watersheds located in Europe and USA (25%). A significant reduction of the uncertainty of our N budget estimate for Lake Victoria Basin would be possible if better data on livestock systems and riverine N export were available. Our study indicates that at present soil N mining is the main source of nitrogen in the Lake Victoria Basin. Thus, sustainable N management requires increasing agricultural N inputs to guarantee food security and rehabilitation and protection of soils to minimize environmental costs. Moreover, to reduce N pollution of the lake, improving management of human and animal wastes needs to be carefully considered in future.

  19. Changes in bacterial community metabolism and composition during the degradation of dissolved organic matter from the jellyfish Aurelia aurita in a Mediterranean coastal lagoon.

    PubMed

    Blanchet, Marine; Pringault, Olivier; Bouvy, Marc; Catala, Philippe; Oriol, Louise; Caparros, Jocelyne; Ortega-Retuerta, Eva; Intertaglia, Laurent; West, Nyree; Agis, Martin; Got, Patrice; Joux, Fabien

    2015-09-01

    Spatial increases and temporal shifts in outbreaks of gelatinous plankton have been observed over the past several decades in many estuarine and coastal ecosystems. The effects of these blooms on marine ecosystem functioning and particularly on the dynamics of the heterotrophic bacteria are still unclear. The response of the bacterial community from a Mediterranean coastal lagoon to the addition of dissolved organic matter (DOM) from the jellyfish Aurelia aurita, corresponding to an enrichment of dissolved organic carbon (DOC) by 1.4, was assessed for 22 days in microcosms (8 l). The high bioavailability of this material led to (i) a rapid mineralization of the DOC and dissolved organic nitrogen from the jellyfish and (ii) the accumulation of high concentrations of ammonium and orthophosphate in the water column. DOM from jellyfish greatly stimulated heterotrophic prokaryotic production and respiration rates during the first 2 days; then, these activities showed a continuous decay until reaching those measured in the control microcosms (lagoon water only) at the end of the experiment. Bacterial growth efficiency remained below 20%, indicating that most of the DOM was respired and a minor part was channeled to biomass production. Changes in bacterial diversity were assessed by tag pyrosequencing of partial bacterial 16S rRNA genes, DNA fingerprints, and a cultivation approach. While bacterial diversity in control microcosms showed little changes during the experiment, the addition of DOM from the jellyfish induced a rapid growth of Pseudoalteromonas and Vibrio species that were isolated. After 9 days, the bacterial community was dominated by Bacteroidetes, which appeared more adapted to metabolize high-molecular-weight DOM. At the end of the experiment, the bacterial community shifted toward a higher proportion of Alphaproteobacteria. Resilience of the bacterial community after the addition of DOM from the jellyfish was higher for metabolic functions than diversity

  20. Jellyfish: Special Tools for Biological Research on Earth and in Space

    NASA Technical Reports Server (NTRS)

    Spangenberg, Dorothy B.

    1991-01-01

    The most intriguing nature of the jellyfish polyps is their ability to metamorphose, giving rise to tiny immature medusae called ephyrae which have a different form or shape from the polyps. The Aurelia Metamorphosis Test System was used to determine the subtle effects of hydrocarbons found in oil spills and the effects of X-irradiation on developing ephyrae. Currently, this test system is used to determine the effects of the gravity-less environment of outer space on the development and behavior of ephyrae. For this purpose, the effects of clinostat rotation on development of the ephyrae and their gravity receptor are being studied. The behavior of the ephyrae during 0 gravity achieved for short intervals of 30 seconds in parabolic flight is examined. The developing ephyrae and the mature ephyrae are exposed to gravity-less environment of outer space via a six or seven day shuttle experiment. If gravity receptors do form in outer space, they will be studied in detail using various types of microscopes, including the electron microscope, to determin whether they developed normally in space as compared with control on Earth.

  1. The state of water in living systems: from the liquid to the jellyfish.

    PubMed

    Henry, M

    2005-12-14

    The status of water in living systems is reviewed both from philosophical and scientific viewpoints. Starting from antique Mediterranean civilizations (Sumerian, Egyptian, Hebrew, Greek), a world trip is proposed through Norse myths, Siberian Shamanism, Hinduism, Taoism, Buddhism, Shinto, Mayan, Aztec, Inca, Aboriginal and African philosophies in order to convince that all humans share the same qualitative idea that water was a pre-requisite for life apparition. The quantitative aspect of the problem is further analyzed at the light of the scientific contributions from two leading scientists: R.A. Gortner and E.T. Jaynes. With Gortner's work it is demonstrated using the concrete example of the Jellyfish submitted at a Faraday discussion held in London in 1930, how a paradigm shift has occurred in the thirties concerning the status of bound water in the living cell. With Jaynes' work, the disastrous consequences of the entrenchment of diffusion theory in biology are critically examined and the exact meaning of the second law of thermodynamics for biological systems is given using the concrete example of muscle contraction. In conclusion, the importance of distinguishing between an ontological and epistemological level of knowledge is stressed and suggestions for reconciling scientific and philosophical approaches are given.

  2. To flap or not to flap: a discussion between a fish and a jellyfish

    NASA Astrophysics Data System (ADS)

    Martin, Nathan; Roh, Chris; Idrees, Suhail; Gharib, Morteza

    2016-11-01

    Fish and jellyfish are known to swim by flapping and by periodically contracting respectively, but which is the more effective propulsion mechanism? In an attempt to answer this question, an experimental comparison is made between simplified versions of these motions to determine which generates the greatest thrust for the least power. The flapping motion is approximated by pitching plates while periodic contractions are approximated by clapping plates. A machine is constructed to operate in either a flapping or a clapping mode between Reynolds numbers 1,880 and 11,260 based on the average plate tip velocity and span. The effect of the total sweep angle, total sweep time, plate flexibility, and duty cycle are investigated. The average thrust generated and power required per cycle are compared between the two modes when their total sweep angle and total sweep time are identical. In general, operating in the clapping mode required significantly more power to generate a similar thrust compared to the flapping mode. However, modifying the duty cycle for clapping caused the effectiveness to approach that of flapping with an unmodified duty cycle. These results suggest that flapping is the more effective propulsion mechanism within the range of Reynolds numbers tested. This work was supported by the Charyk Bio-inspired Laboratory at the California Institute of Technology, the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469, and the Summer Undergraduate Research Fellowships program.

  3. The Jellyfish hunter--Jack Barnes: a pioneer medical toxinologist in Australia.

    PubMed

    Pearn, John; Fenner, Peter

    2006-12-01

    Dr Jack Handyside Barnes (1922-1985) was one of the small and elite group of Pacific marine toxinologists whose work was characterised by an uncompromising rugged persona, a focussed resolve to solve challenging problems of human clinical envenomation, and who conducted curiosity-driven research under conditions of scientific isolation. He was a pioneering advocate for the preservation of marine heritage, particularly that of the Great Barrier Reef. A former military commando who later became a general medical practitioner with extensive surgical and obstetric skills, in 1947 he was appointed the Medical Superintendent of Thursday Island in the Torres Strait. Later (from January 1953), he worked indefatigably as a general medical practitioner in Cairns, in tropical North Australia. For four decades (1945-1985), Jack Barnes undertook detailed laboratory, clinical and field research into invertebrate envenomation, particularly medusan toxinology. In 1960 he discovered the species responsible for the Irukandji syndrome, a small carybdeid named Carukia barnesi in his honour. He invented the research technique for the extraction of venom from the world's most venomous creature, the Pacific box Jellyfish, Chironex fleckeri. By 1960, he had published taxonomic details of nematocyst structure and clinical envenomation details consequent upon stings by Physalia, Cyanea, Chironex, Chiropsalmus and Carukia. This paper is a précis of the chronology of his life, contributions and influence.

  4. A specific antimicrobial protein CAP-1 from Pseudomonas sp. isolated from the jellyfish Cyanea capillata.

    PubMed

    Yin, Manman; Liu, Dan; Xu, Feng; Xiao, Liang; Wang, Qianqian; Wang, Beilei; Chang, Yinlong; Zheng, Jiemin; Tao, Xia; Liu, Guoyan; Zhang, Liming

    2016-01-01

    A bacterium strain, designated as CMF-2, was isolated from the jellyfish Cyanea capillata and its culture supernatant exhibited a significant antimicrobial activity. The strain CMF-2 was identified as Pseudomonas sp. based on the morphological, biochemical and physiological characteristics as well as 16S rRNA sequence analysis. In this study, an antimicrobial protein, named as CAP-1, was isolated from the culture of CMF-2 through ammonium sulfate precipitation and gel filtration chromatography. According to the result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), a major band indicated that the antimicrobial protein had a molecular mass of about 15 kDa, and it was identified as a hypothetical protein by MALDI-TOF-MS analysis and Mascot searching. CAP-1 displayed a broad antimicrobial spectrum against the indicator bacteria and fungus, including Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Candida albicans, especially some marine-derived microorganisms such as Vibrio vulnificus, Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio cholera, and Vibrio anguillarum, but showed little impact on tumor cells and normal human cells. The protein CAP-1 remained a stable antimicrobial activity in a wide range of temperature (20-80°C) and pH (2-10) conditions. These results suggested that CAP-1 might have a specific antimicrobial function not due to cytotoxicity.

  5. Jellyfish skin polysaccharides: extraction and inhibitory activity on macrophage-derived foam cell formation.

    PubMed

    Zhang, Hai-Lin; Cui, Shao-Hua; Zha, Xue-Qiang; Bansal, Vibha; Xue, Lei; Li, Xiao-Long; Hao, Ran; Pan, Li-Hua; Luo, Jian-Ping

    2014-06-15

    In this work, response surface methodology was used to determine optimum conditions for extraction of polysaccharides from jellyfish skin (JSP). The optimum parameters were found to be raw material to water ratio 1:7.5 (w/v), extraction temperature 100°C and extraction time 4h. Under these conditions, the JSP yield reached 1.007 mg/g. Papain (15 U/mL) in combination with Sevag reagent was beneficial in removing proteins from JSP. After precipitation with ethanol at final concentration of 40%, 60% and 80% in turn, three polysaccharide fractions of JSP1, JSP2 and JSP3 were obtained from JSP, respectively. The three fractions exhibited different physicochemical properties with respect to molecular weight distribution, monosaccharide composition, infrared absorption spectra, and glycosyl bond composition. In addition, JSP3 showed strong inhibitory effects on oxidized low-density lipoprotein (oxLDL) induced conversion of macrophages into foam cells, which possibly attributed to the down-regulation of some atherogenesis-related gene expressions.

  6. Cardiovascular effects of Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom in rats.

    PubMed

    Kim, Euikyung; Lee, Seunghwan; Kim, Jong-Shu; Yoon, Won Duk; Lim, Donghyun; Hart, Andrew J; Hodgson, Wayne C

    2006-12-15

    Over the past few years, populations of the giant jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae) have increased dramatically in the waters of China, Korea, and Japan without any definitive reason. This has resulted in severe damage to fisheries in the areas. During a pilot study, we observed that the venom of N. nomurai produced a functional cardiac depression in mice. However, the mechanism of action was not examined. In the present study, we investigated the cardiovascular effects of nematocyst-derived venom from N. nomurai in anesthetized rats. Venom (0.1-2.4 mg protein/kg, i.v.) produced dose-dependent hypotension (65+/-12% of initial at a cumulative dose of 3 mg/kg) and bradycardia (80+/-5% of initial at a cumulative dose of 3 mg/kg). At the highest dose, this was characterized by a transient decrease in blood pressure (phase 1) followed by a return to basal level and then a slower decrease in blood pressure (phase 2). Venom also produced a decrease in rate and force of contraction in the rat isolated atria. Interestingly, venom induced a contraction of isolated aortic rings which was blocked by felodipine but not by prazosin, suggesting the contraction is mediated by calcium channel activation. These results suggest that the negative inotropic and chronotropic effects of the venom of N. nomurai may be due to a direct effect on the heart.

  7. ACE Inhibitory and Antioxidant Activities of Collagen Hydrolysates from the Ribbon Jellyfish (Chrysaora sp.)

    PubMed Central

    Latiff, Aishah Abd; Gan, Chee-Yuen; Abedin, Md. Zainul; Alias, Abd Karim

    2014-01-01

    Summary Collagen isolated from the ribbon jellyfish (Chrysaora sp.) was hydrolysed using three different proteases (i.e. trypsin, alcalase and Protamex) to obtain bioactive peptides. Angiotensin-I-converting enzyme (ACE) inhibitory activity and antioxidant activities (i.e. ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity) of the peptides were measured and compared, and the effect of the duration of hydrolysis on the bioactivity (ACE inhibitory and antioxidant activities) of peptides was also evaluated. FRAP activity was the highest in Protamex-induced (25–27 mM) and trypsin-induced hydrolysates (24–26 mM) at 7 and 9 h, respectively. Conversely, hydrolysates produced by trypsin for 1 and 3 h showed the highest DPPH radical scavenging activities (94 and 92%, respectively). Trypsin-induced hydrolysates (at 3 h) also showed the highest ACE inhibitory activity (89%). The peptide sequences with the highest activities were identified using tandem mass spectrometry, and the results show that the hydrolysates had a high content of hydrophobic amino acids as well as unique amino acid sequences, which likely contribute to their biological activities. PMID:27904323

  8. Heavy metals affect regulatory volume decrease (RVD) in nematocytes isolated from the jellyfish Pelagia noctiluca.

    PubMed

    Morabito, R; Marino, A; La Spada, G

    2013-06-01

    The environmental contamination caused by heavy metals raises the question of their effect on biological systems. Among bio-indicators useful to monitor the toxicological effects of these chemicals, Cnidarians offer a unique model. Cnidarians possess highly specialized stinging cells, termed nematocytes, which respond to hyposmotic solution with well established homeostatic parameters as an acute osmotic phase (OP), leading to cell swelling, and then a slower regulatory volume decrease (RVD) phase, causing cell shrinkage. Here we report the effect of 65% artificial sea water (ASW) containing heavy metals, such as Cd, La, Co, Cu and Zn (concentrations comprised between 100 and 0.1 μM) on both OP and RVD in nematocytes isolated from the jellyfish Pelagia noctiluca by 605 mM NaSCN plus 0.01 mM Ca(2+). The exposure of the cells to Co and La inhibited RVD but not OP. However, Cu, Cd and Zn prevented the OP in a dose-dependent manner and, hence, also the detection of RVD. These results suggest that, in isolated nematocytes, heavy metal pollutants impair RVD either directly or indirectly through interference with the OP, thus negating RVD. Although further studies need to clarify the exact mechanisms whereby heavy metals exert their toxicity, it is evident that nematocytes of Cnidarians could serve as a model for ecotoxicological investigations.

  9. Fluorescent Proteins as Biomarkers and Biosensors: Throwing Color Lights on Molecular and Cellular Processes

    PubMed Central

    Stepanenko, Olesya V.; Verkhusha, Vladislav V.; Kuznetsova, Irina M.; Uversky, Vladimir N.; Turoverov, K.K.

    2010-01-01

    Green fluorescent protein (GFP) from jellyfish Aequorea victoria is the most extensively studied and widely used in cell biology protein. GFP-like proteins constitute a fast growing family as several naturally occurring GFP-like proteins have been discovered and enhanced mutants of Aequorea GFP have been created. These mutants differ from wild-type GFP by conformational stability, quantum yield, spectroscopic properties (positions of absorption and fluorescence spectra) and by photochemical properties. GFP-like proteins are very diverse, as they can be not only green, but also blue, orange-red, far-red, cyan, and yellow. They also can have dual-color fluorescence (e.g., green and red) or be non-fluorescent. Some of them possess kindling property, some are photoactivatable, and some are photoswitchable. This review is an attempt to characterize the main color groups of GFP-like proteins, describe their structure and mechanisms of chromophore formation, systemize data on their conformational stability and summarize the main trends of their utilization as markers and biosensors in cell and molecular biology. PMID:18691124

  10. Fluorescent proteins as biomarkers and biosensors: throwing color lights on molecular and cellular processes.

    PubMed

    Stepanenko, Olesya V; Verkhusha, Vladislav V; Kuznetsova, Irina M; Uversky, Vladimir N; Turoverov, K K

    2008-08-01

    Green fluorescent protein (GFP) from jellyfish Aequorea victoria is the most extensively studied and widely used in cell biology protein. GFP-like proteins constitute a fast growing family as several naturally occurring GFP-like proteins have been discovered and enhanced mutants of Aequorea GFP have been created. These mutants differ from wild-type GFP by conformational stability, quantum yield, spectroscopic properties (positions of absorption and fluorescence spectra) and by photochemical properties. GFP-like proteins are very diverse, as they can be not only green, but also blue, orange-red, far-red, cyan, and yellow. They also can have dual-color fluorescence (e.g., green and red) or be non-fluorescent. Some of them possess kindling property, some are photoactivatable, and some are photoswitchable. This review is an attempt to characterize the main color groups of GFP-like proteins, describe their structure and mechanisms of chromophore formation, systemize data on their conformational stability and summarize the main trends of their utilization as markers and biosensors in cell and molecular biology.

  11. 75 FR 71467 - Exelon Nuclear Texas Holdings, LLC, Early Site Permit Application for the Victoria County Station...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-23

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION Exelon Nuclear Texas Holdings, LLC, Early Site Permit Application for the Victoria County Station... Contention Preparation AGENCY: Nuclear Regulatory Commission (NRC or the Commission). ACTION: Notice...

  12. Draft Genome Sequences of 15 Staphylococcus aureus Isolates Recovered from Raw Milk and Associated Milk Filters from Victoria, Australia

    PubMed Central

    McMillan, Kate; Allnutt, Theodore R.

    2017-01-01

    ABSTRACT This study describes draft whole genomes of 15 Staphylococcus aureus isolates from dairy farms located in Victoria, Australia. Two novel sequence types (ST3183 and ST3184) were identified among these isolates. PMID:28082499

  13. 78 FR 60826 - Foreign-Trade Zone 155-Calhoun/Victoria Counties, Texas; Authorization of Production Activity...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-02

    ... Production Activity; Caterpillar, Inc. (Excavator and Frame Assembly Production); Victoria, Texas On May 29... proposed production activity to the Foreign-Trade Zones (FTZ) Board on behalf of Caterpillar, Inc.,...

  14. A pharmacological investigation of the venom extract of the Australian box jellyfish, Chironex fleckeri, in cardiac and vascular tissues.

    PubMed

    Hughes, Richard J A; Angus, James A; Winkel, Kenneth D; Wright, Christine E

    2012-02-25

    The pharmacology of Australian box jellyfish, Chironex fleckeri, unpurified (crude) nematocyst venom extract (CVE) was investigated in rat isolated cardiac and vascular tissues and in anaesthetised rats. In small mesenteric arteries CVE (0.01-30 μg/ml) caused contractions (EC(50) 1.15±0.19 μg/ml) that were unaffected by prazosin (0.1 μM), bosentan (10 μM), CGRP(8-37) (1 μM) or tetrodotoxin (1 μM). Box jellyfish antivenom (5-92.6 units/ml) caused rightward shifts of the CVE concentration-response curve with no change in the maximum. In the presence of l-NAME (100 μM) the sensitivity and maximum response to CVE were increased, whilst MgSO(4) (6 mM) decreased both parameters. CVE (1-10 μg/ml) caused inhibition of the contractile response to electrical sympathetic nerve stimulation. Left atrial responses to CVE (0.001-30 μg/ml) were bi-phasic, composed of an initial positive inotropy followed by a marked negative inotropy and atrial standstill. CVE (0.3 μg/ml) elicited a marked decrease in right atrial rate followed by atrial standstill at 3 μg/ml. These responses were unaffected by 1 μM of propranolol, atropine or CGRP(8-37). Antivenom (54 and 73 units/ml) caused rightward shifts of the CVE concentration-response curve and prevented atrial standstill in left and right atria. The effects of CVE do not appear to involve autonomic nerves, post-synaptic α(1)- or β(1)-adrenoceptors, or muscarinic, endothelin or CGRP receptors, but may occur through direct effects on the cardiac and vascular muscle. Box jellyfish antivenom was effective in attenuating CVE-induced responses in isolated cardiac and vascular tissues.

  15. Clearance rates of ephyrae and small medusae of the common jellyfish Aurelia aurita offered different types of prey

    NASA Astrophysics Data System (ADS)

    Riisgård, Hans Ulrik; Madsen, Caroline V.

    2011-01-01

    Prey selection and knowledge of the amounts of water processed by the early stages of the common jellyfish Aurelia aurita may at certain times of the year be crucial for understanding the plankton dynamics in marine ecosystems with mass occurrences of this jellyfish. In the present study we used two different methods ("clearance method" and "ingestion-rate method") to estimate the amount of water cleared per unit of time of different types and sizes of prey organisms offered to A. aurita ephyrae and small medusae. The mean clearance rates of medusae, estimated with Artemia sp. nauplii as prey by both methods, agreed well, namely 3.8 ± 1.4 l h - 1 by the clearance method and 3.2 ± 1.1 l h - 1 by the ingestion-rate method. Both methods showed that copepods (nauplii and adults) and mussel veligers are captured with considerably lower efficiency, 22 to 37% and 14 to 30%, respectively, than Artemia salina nauplii. By contrast, the water processing rates of ephyrae measured by the clearance method with A. salina nauplii as prey were 3 to 5 times lower than those measured by the ingestion-rate method. This indicates that the prerequisite of full mixing for using the clearance method may not have been fulfilled in the ephyrae experiments. The study demonstrates that the predation impact of the young stages of A. aurita is strongly dependent on its developmental stage (ephyra versus medusa), and the types and sizes of prey organisms. The estimated prey-digestion time of 1.3 h in a steady-state feeding experiment with constant prey concentration supports the reliability of the ingestion-rate method, which eliminates the negative "container effects" of the clearance method, and it seems to be useful in future jellyfish studies, especially on small species/younger stages in which both type and number of prey can be easily and precisely assessed.

  16. Flexibly deployed Pax genes in eye development at the early evolution of animals demonstrated by studies on a hydrozoan jellyfish.

    PubMed

    Suga, Hiroshi; Tschopp, Patrick; Graziussi, Daria F; Stierwald, Michael; Schmid, Volker; Gehring, Walter J

    2010-08-10

    Pax transcription factors are involved in a variety of developmental processes in bilaterians, including eye development, a role typically assigned to Pax-6. Although no true Pax-6 gene has been found in nonbilateral animals, some jellyfish have eyes with complex structures. In the cubozoan jellyfish Tripedalia, Pax-B, an ortholog of vertebrate Pax-2/5/8, had been proposed as a regulator of eye development. Here we have isolated three Pax genes (Pax-A, Pax-B, and Pax-E) from Cladonema radiatum, a hydrozoan jellyfish with elaborate eyes. Cladonema Pax-A is strongly expressed in the retina, whereas Pax-B and Pax-E are highly expressed in the manubrium, the feeding and reproductive organ. Misexpression of Cladonema Pax-A induces ectopic eyes in Drosophila imaginal discs, whereas Pax-B and Pax-E do not. Furthermore, Cladonema Pax-A paired domain protein directly binds to the 5' upstream region of eye-specific Cladonema opsin genes, whereas Pax-B does not. Our data suggest that Pax-A, but not Pax-B or Pax-E, is involved in eye development and/or maintenance in Cladonema. Phylogenetic analysis indicates that Pax-6, Pax-B, and Pax-A belong to different Pax subfamilies, which diverged at the latest before the Cnidaria-Bilateria separation. We argue that our data, showing the involvement of Pax genes in hydrozoan eye development as in bilaterians, supports the monophyletic evolutionary origin of all animal eyes. We then propose that during the early evolution of animals, distinct classes of Pax genes, which may have played redundant roles at that time, were flexibly deployed for eye development in different animal lineages.

  17. In depth analysis of the in vivo toxicity of venom from the jellyfish Stomolophus meleagris.

    PubMed

    Li, Rongfeng; Yu, Huahua; Yue, Yang; Liu, Song; Xing, Ronge; Chen, Xiaolin; Wang, Xueqin; Li, Pengcheng

    2014-12-15

    Jellyfish Stomolophus meleagris, a synonym of Nemopilema nomurai, which has often bloomed in the China Sea in recent years, is becoming an increasing threat to human health and life as a result of its strong toxicity. Each year, hundreds of thousands of people were stung, especially in the high season, and the victims suffered itch, edema, myalgia, dyspnea, hypotension, shock and even death. Here, we present the in-depth analysis of the in vivo toxicity of the venom from the jellyfish S. meleagris by using both an acute toxicological approach and pathological analyses. The venom showed an LD50 of approximately 2.92 μg/g body weight in mice following an intravenous injection and caused renal glomerular swelling, renal vesicle stricture, renal tubules dilatation, hepatic blood sinusoid dilatation, pulmonary edema and malignant pleural effusion. The pathological sections analysis showed that the kidney and liver were significantly damaged, but the heart, spleen and stomach had no observed changes. Additionally, the hemanalysis showed an increase of white blood cells (WBC), middle cells (Mid), alanine aminotransferase (ALT), blood urine nitrogen (BUN) and uric acid (UA) in the blood. Moreover, the mice also displayed convulsions, mouth bleeding, piloerection, dyspnea and death after the injection of the venom. In conclusion, this venom has a strong toxicity to the kidney of the mice and the acute renal failure might be one of the most important factors for the death after a severe sting. Hopefully, the present study will provide a significant reference for the treatment of stings by the jellyfish S. meleagris in the future.

  18. Jellyfish support high energy intake of leatherback sea turtles (Dermochelys coriacea): video evidence from animal-borne cameras.

    PubMed

    Heaslip, Susan G; Iverson, Sara J; Bowen, W Don; James, Michael C

    2012-01-01

    The endangered leatherback turtle is a large, highly migratory marine predator that inexplicably relies upon a diet of low-energy gelatinous zooplankton. The location of these prey may be predictable at large oceanographic scales, given that leatherback turtles perform long distance migrations (1000s of km) from nesting beaches to high latitude foraging grounds. However, little is known about the profitability of this migration and foraging strategy. We used GPS location data and video from animal-borne cameras to examine how prey characteristics (i.e., prey size, prey type, prey encounter rate) correlate with the daytime foraging behavior of leatherbacks (n = 19) in shelf waters off Cape Breton Island, NS, Canada, during August and September. Video was recorded continuously, averaged 1:53 h per turtle (range 0:08-3:38 h), and documented a total of 601 prey captures. Lion's mane jellyfish (Cyanea capillata) was the dominant prey (83-100%), but moon jellyfish (Aurelia aurita) were also consumed. Turtles approached and attacked most jellyfish within the camera's field of view and appeared to consume prey completely. There was no significant relationship between encounter rate and dive duration (p = 0.74, linear mixed-effects models). Handling time increased with prey size regardless of prey species (p = 0.0001). Estimates of energy intake averaged 66,018 kJ • d(-1) but were as high as 167,797 kJ • d(-1) corresponding to turtles consuming an average of 330 kg wet mass • d(-1) (up to 840 kg • d(-1)) or approximately 261 (up to 664) jellyfish • d(-1). Assuming our turtles averaged 455 kg body mass, they consumed an average of 73% of their body mass • d(-1) equating to an average energy intake of 3-7 times their daily metabolic requirements, depending on estimates used. This study provides evidence that feeding tactics used by leatherbacks in Atlantic Canadian waters are highly profitable and our results are consistent with estimates of mass gain prior to

  19. The Cambrian Ross Orogeny in northern Victoria Land (Antarctica) and New Zealand: A synthesis

    USGS Publications Warehouse

    Federico, L.; Capponi, G.; Crispini, L.; Bradshaw, J.D.

    2007-01-01

    In the Cambrian, the paleo-Pacific margin of the Gondwana supercontinent included East Antarctica, Australia, Tasmania and New Zealand and was affected by themajor Ross-Delamerian Orogeny. In Antarctica, evidence suggests that this resulted from oblique subduction and that in northern Victoria Land it was accompanied by the opening and subsequent closure of a back-arc basin. Comparison of the type and timing of sedimentary, magmatic and metamorphic events in areas noted above shows strong similarities between northern Victoria Land and New Zealand. In both regions Middle Cambrian volcanites are interpreted as arc/back-arc assemblages produced by west-directed subduction; sediments interbedded with the volcanites show provenance both from the arc and from the Gondwana margin and therefore place the basin close to the continent. Back-arc closure in the Late Cambrian was likely accomplished through a second subduction system

  20. Strain and displacement measurements for the June 9, 1980 Victoria, Mexico Earthquake

    NASA Astrophysics Data System (ADS)

    Darby, D.; Nyland, E.; Suarez, F.; Chavez, D.; Gonzalez, J.

    A microgeodetic network 22 km south east of Est. Guadalupe Victoria, Baja California Norte, installed in late May 1980, has been resurveyed in an experiment that started 12 hours after the June 9, 1980 Victoria earthquake, which had an epicenter at 10 km depth about 12 km from the network. The resurvey was complete by June 13. Both the initial observations and the resurvey were done with HP3800 distance meter equipment. Some angular control was provided with a Wild T3 theodolite. The network underwent a compressive strain of 7 ± 3 micro strain essentially parallel the Cerro Prieto fault about the time of the earthquake. Strains of this size are associated with simple dislocation models of earthquakes of this magnitude. Its direction appears to be anomalous however. This may indicate compression related to soil liquefaction processes or strain near the end of the slip plane.

  1. Environmental impacts of cage culture in Lake Victoria: the case of Shirati Bay-Sota, Tanzania.

    PubMed

    Kashindye, Benedicto Boniphace; Nsinda, P; Kayanda, R; Ngupula, G W; Mashafi, C A; Ezekiel, C N

    2015-01-01

    The experimental cage culture was conducted at Shirati bay, Lake Victoria from February to August 2013, to investigate the impacts of the small scale cage culture on the environment. Three locations along the cages, at the intermediate and one in the offshore (control) were sampled for water quality parameters, phytoplankton and macro invertebrates. A notable increase in nutrient concentration was observed after the set of cages among the stations. However DO, pH, and water transparency showed no major changes and was within the recommended ranges. Cyanophytes an indicator of inorganic pollution dominated before and after the set of cages, an increase in phytoplankton numerical abundance was observed after stocking of fish in cages. In addition there was an increase in the invertebrate community especially bivalves and gastropods. In conclusion we found no consistent environmental change caused by cage culture, and therefore it can be allowed in Lake Victoria, Tanzania part, with close monitoring of its impacts.

  2. A fresh insight into transmission of schistosomiasis: a misleading tale of Biomphalaria in Lake Victoria.

    PubMed

    Standley, Claire J; Wade, Christopher M; Stothard, J Russell

    2011-01-01

    Lake Victoria is a known hot-spot for Schistosoma mansoni, which utilises freshwater snails of the genus Biomphalaria as intermediate hosts. Different species of Biomphalaria are associated with varying parasite compatibility, affecting local transmission. It is thought that two species, B. choanomphala and B. sudanica, inhabit Lake Victoria; despite their biomedical importance, the taxonomy of these species has not been thoroughly examined. This study combined analysis of morphological and molecular variables; the results demonstrated that molecular groupings were not consistent with morphological divisions. Habitat significantly predicted morphotype, suggesting that the different Lake Victorian forms of Biomphalaria are ecophentoypes of one species. The nomenclature should be revised accordingly; the names B. choanomphala choanomphala and B. c. sudanica are proposed. From a public health perspective, these findings can be utilised by policy-makers for better understanding of exposure risk, resulting in more effective and efficient control initiatives.

  3. [Occurrence and seasonal changes of antibiotics in the Victoria Harbour and the Pearl River, South China].

    PubMed

    Xu, Wei-hai; Zhang, Gan; Zou, Shi-chun; Li, Xiang-dong; Liu, Yu-chun

    2006-12-01

    The occurrence and seasonal changes of antibiotics in the Victoria Harbour and the Pearl River were studied using high-performance liquid chromatography-electrospray ionization tandem mass spectrometry with multiple reaction monitoring (MRM). The results showed that the concentrations of antibiotics were mainly below the limit of quantification (LOQ) in the ambient marine water of Victoria Harbour. However, except for amoxicillin, all the target antibiotics were detected in the Pearl River during high (summer) and low (early spring) water seasons with the concentrations ranging from 13 to 69 ng x L(-1) and from 70 to 489 ng x L(-1), respectively. The concentrations of antibiotics in the Pearl River are all higher than that in America and other western developed countries, no matter in spring or summer. The concentrations of antibiotics showed sensitive daily changes in the high water season.

  4. VLUIS, a land use data product for Victoria, Australia, covering 2006 to 2013.

    PubMed

    Morse-McNabb, Elizabeth; Sheffield, Kathryn; Clark, Rob; Lewis, Hayden; Robson, Susan; Cherry, Don; Williams, Steve

    2015-11-24

    Land Use Information is a key dataset required to enable an understanding of the changing nature of our landscapes and the associated influences on natural resources and regional communities. The Victorian Land Use Information System (VLUIS) data product has been created within the State Government of Victoria to support land use assessments. The project began in 2007 using stakeholder engagement to establish product requirements such as format, classification, frequency and spatial resolution. Its genesis is significantly different to traditional methods, incorporating data from a range of jurisdictions to develop land use information designed for regular on-going creation and consistency. Covering the entire landmass of Victoria, the dataset separately describes land tenure, land use and land cover. These variables are co-registered to a common spatial base (cadastral parcels) across the state for the period 2006 to 2013; biennially for land tenure and land use, and annually for land cover. Data is produced as a spatial GIS feature class.

  5. VLUIS, a land use data product for Victoria, Australia, covering 2006 to 2013

    PubMed Central

    Morse-McNabb, Elizabeth; Sheffield, Kathryn; Clark, Rob; Lewis, Hayden; Robson, Susan; Cherry, Don; Williams, Steve

    2015-01-01

    Land Use Information is a key dataset required to enable an understanding of the changing nature of our landscapes and the associated influences on natural resources and regional communities. The Victorian Land Use Information System (VLUIS) data product has been created within the State Government of Victoria to support land use assessments. The project began in 2007 using stakeholder engagement to establish product requirements such as format, classification, frequency and spatial resolution. Its genesis is significantly different to traditional methods, incorporating data from a range of jurisdictions to develop land use information designed for regular on-going creation and consistency. Covering the entire landmass of Victoria, the dataset separately describes land tenure, land use and land cover. These variables are co-registered to a common spatial base (cadastral parcels) across the state for the period 2006 to 2013; biennially for land tenure and land use, and annually for land cover. Data is produced as a spatial GIS feature class. PMID:26602150

  6. A Fresh Insight into Transmission of Schistosomiasis: A Misleading Tale of Biomphalaria in Lake Victoria

    PubMed Central

    Standley, Claire J.; Wade, Christopher M.; Stothard, J. Russell

    2011-01-01

    Lake Victoria is a known hot-spot for Schistosoma mansoni, which utilises freshwater snails of the genus Biomphalaria as intermediate hosts. Different species of Biomphalaria are associated with varying parasite compatibility, affecting local transmission. It is thought that two species, B. choanomphala and B. sudanica, inhabit Lake Victoria; despite their biomedical importance, the taxonomy of these species has not been thoroughly examined. This study combined analysis of morphological and molecular variables; the results demonstrated that molecular groupings were not consistent with morphological divisions. Habitat significantly predicted morphotype, suggesting that the different Lake Victorian forms of Biomphalaria are ecophentoypes of one species. The nomenclature should be revised accordingly; the names B. choanomphala choanomphala and B. c. sudanica are proposed. From a public health perspective, these findings can be utilised by policy-makers for better understanding of exposure risk, resulting in more effective and efficient control initiatives. PMID:22046308

  7. New fossil teeth of Theropithecus oswaldi (Cercopithecoidea) from the Early Pleistocene at Cueva Victoria (SE Spain).

    PubMed

    Ferràndez-Cañadell, Carles; Ribot, Francesc; Gibert, Lluís

    2014-09-01

    The presence of Theropithecus oswaldi in Europe was first reported in 1995 from the Early Pleistocene site of Cueva Victoria (SE Spain), showing the dispersal of this genus above 30° north latitude and into Europe. Later claims of the presence in Italy of Theropithecus in the Early Pleistocene, based on vertebral remains, are controversial. Here we report four additional teeth of T. oswaldi from Cueva Victoria. These and the previously described tooth correspond to a minimum of two individuals. The presence of T. oswaldi in North Africa and SE Iberia during the Early Pleistocene suggests a possible faunal dispersal from Africa into Europe through the Straits of Gibraltar, which would have acted as a filter bridge.

  8. B chromosomes have a functional effect on female sex determination in Lake Victoria cichlid fishes.

    PubMed

    Yoshida, Kohta; Terai, Yohey; Mizoiri, Shinji; Aibara, Mitsuto; Nishihara, Hidenori; Watanabe, Masakatsu; Kuroiwa, Asato; Hirai, Hirohisa; Hirai, Yuriko; Matsuda, Yoichi; Okada, Norihiro

    2011-08-01

    The endemic cichlid fishes in Lake Victoria are a model system for speciation through adaptive radiation. Although the evolution of the sex-determination system may also play a role in speciation, little is known about the sex-determination system of Lake Victoria cichlids. To understand the evolution of the sex-determination system in these fish, we performed cytogenetic analysis in 11 cichlid species from Lake Victoria. B chromosomes, which are present in addition to standard chromosomes, were found at a high prevalence rate (85%) in these cichlids. In one species, B chromosomes were female-specific. Cross-breeding using females with and without the B chromosomes demonstrated that the presence of the B chromosomes leads to a female-biased sex ratio in this species. Although B chromosomes were believed to be selfish genetic elements with little effect on phenotype and to lack protein-coding genes, the present study provides evidence that B chromosomes have a functional effect on female sex determination. FISH analysis using a BAC clone containing B chromosome DNA suggested that the B chromosomes are derived from sex chromosomes. Determination of the nucleotide sequences of this clone (104.5 kb) revealed the presence of several protein-coding genes in the B chromosome, suggesting that B chromosomes have the potential to contain functional genes. Because some sex chromosomes in amphibians and arthropods are thought to be derived from B chromosomes, the B chromosomes in Lake Victoria cichlids may represent an evolutionary transition toward the generation of sex chromosomes.

  9. Late Pleistocene Desiccation of Lake Victoria and Rapid Evolution of Cichlid Fishes

    NASA Astrophysics Data System (ADS)

    Johnson, Thomas C.; Scholz, Christopher A.; Talbot, Michael R.; Kelts, Kerry; Ricketts, R. D.; Ngobi, Gideon; Beuning, Kristina; Ssemmanda, Immacculate; McGill, J. W.

    1996-08-01

    Lake Victoria is the largest lake in Africa and harbors more than 300 endemic species of haplochromine cichlid fish. Seismic reflection profiles and piston cores show that the lake not only was at a low stand but dried up completely during the Late Pleistocene, before 12,400 carbon-14 years before the present. These results imply that the rate of speciation of cichlid fish in this tropical lake has been extremely rapid.

  10. Satellite-Based Assessment of the spatial extent of Aquatic Vegetation in Lake Victoria

    NASA Astrophysics Data System (ADS)

    Clark, W.; Aligeti, N.; Jeyaprakash, T.; Martins, M.; Stodghill, J.; Winstanley, H.

    2011-12-01

    Lake Victoria in Africa is the second largest freshwater lake in the world and is known for its abundance of aquatic wildlife. In particular over 200 different fish species are caught and sold by local fisherman. The lake is a major contributor to the local economy as a corridor of transportation, source of drinking water, and source of hydropower. However, the invasion of aquatic vegetation such as water hyacinth in the lake has disrupted each of these markets. Aquatic vegetation now covers a substantial area of the coastline blocking waterways, disrupting hydropower, hindering the collection of drinking water and decreasing the profitability of fishing. The vegetation serves as a habitat for disease carrying mosquitoes as well as snakes and snails that spread the parasitic disease bilharzia. The current control measures of invasive aquatic vegetation rely on biological, chemical and mechanical control. The objective of this study was to utilize remote sensing to map aquatic vegetation within Lake Victoria from 2000 to 2011. MODIS, Landsat 4-5TM, and Landsat 7-ETM imagery was employed to perform change detections in vegetation and identify the extent of aquatic vegetation throughout the years. The efficiency of containment efforts were evaluated and ideal time for application of such efforts were suggested. A methodology for aquatic vegetation surveillance was created. The results of this project were presented as a workshop to the Lake Victoria Fisheries Organization, SERVIR, and other partner organizations. The workshop provided instruction into the use of NASA and other satellite derived products. Time series animations of the spatial extent of aquatic vegetation within the lake were created. By identifying seasons of decreased aquatic vegetation, ideal times to employ control efforts were identified. SERVIR will subsequently utilize the methodologies and mapping results of this study to develop operational aquatic vegetation surveillance for Lake Victoria.

  11. Leuconidae (Crustacea: Cumacea) from the collections of the Museum Victoria, Australia.

    PubMed

    Gerken, Sarah

    2016-01-21

    The collections of the Museum Victoria have yielded six new leuconid species in five genera from Australian waters: Austroleucon adiazetos n. sp., A. dolosolevis n. sp., Eudorellopsis mykteros n. sp., Kontiloleucon australiensis n. gen., n. sp., Leucon (Alytoleucon) dolichorhinos n. sp., Ommatoleucon megalopos n. sp. as well as the new genus Kontiloleucon. Leucon (Leucon) echinolophotos n. sp. is a new species from off Enderby Land, Antarctica. Keys to the Australian leuconid genera and species are included.

  12. Urban eutrophication and its spurring conditions in the Murchison Bay of Lake Victoria.

    PubMed

    Kabenge, Martin; Wang, Hongtao; Li, Fengting

    2016-01-01

    The efficiency of Lake Victoria in providing its ecosystem services to riparian states, both immediate and along the Nile river basin, is strongly related to its water quality. Over the past few decades, eutrophication has increased in the lake arising from increased inflow of nutrients. This study was carried out in the Murchison Bay area of Lake Victoria with the aims of assessing the progress of eutrophication nutrient enrichment into the lake between 1990 and 2014. Using Landsat satellite floating algae index (FAI) products and data from laboratory analysis of water samples, the study revealed that floating algae reoccurred periodically with coverage varying between 1 and 18 km(2). The findings also indicated that the range of nitrate-nitrogen concentrations increased greatly with maximum concentrations recorded at 31.2 mg l(-1) in 2007 from 0.084 mg l(-1) in 1990. The soluble reactive phosphorus concentration range showed a maximum of 1.45 mg l(-1) in 2007 from 0.043 mg l(-1) in 1990. The chlorophyll levels increased from an average of 17 μg l(-1) in 1992 by threefold in 1996 but had however declined and halved in intensity by 2011. The eutrophication that has occurred in Lake Victoria over the past decades has been due to pollution from industrial, residential, and agricultural areas within the catchment.

  13. Parameterization of the inherent optical properties of Murchison Bay, Lake Victoria.

    PubMed

    Okullo, Willy; Ssenyonga, Taddeo; Hamre, Børge; Frette, Oyvind; Sørensen, K; Stamnes, Jakob J; Steigen, Andreas; Stamnes, Knut

    2007-12-20

    Lake Victoria, Africa's largest freshwater lake, suffers greatly from negative changes in biomass of species of fish and also from severe eutrophication. The continuing deterioration of Lake Victoria's ecological functions has great long-term consequences for the ecosystem benefits it provides to the countries bordering its shores. However, knowledge about temporal and spatial variations of optical properties and how they relate to lake constituents is important for a number of reasons such as remote sensing, modeling of underwater light fields, and long-term monitoring of lake waters. Based on statistical analysis of data from optical measurements taken during half a year of weekly cruises in Murchison Bay, Lake Victoria, we present a three-component model for the absorption and a two-component model for the scattering of light in the UV and the visible regions of the solar spectrum along with tests of their ranges of validity. The three-component input to the model for absorption is the chlorophyll-a (Chl-a), total suspended materials concentrations, and yellow substance absorption, while the two-component input to the model for scattering is the Chl-a concentration and total suspended materials.

  14. Parameterization of the inherent optical properties of Murchison Bay, Lake Victoria

    NASA Astrophysics Data System (ADS)

    Okullo, Willy; Ssenyonga, Taddeo; Hamre, Børge; Frette, Øyvind; Sørensen, K.; Stamnes, Jakob J.; Steigen, Andreas; Stamnes, Knut

    2007-12-01

    Lake Victoria, Africa's largest freshwater lake, suffers greatly from negative changes in biomass of species of fish and also from severe eutrophication. The continuing deterioration of Lake Victoria's ecological functions has great long-term consequences for the ecosystem benefits it provides to the countries bordering its shores. However, knowledge about temporal and spatial variations of optical properties and how they relate to lake constituents is important for a number of reasons such as remote sensing, modeling of underwater light fields, and long-term monitoring of lake waters. Based on statistical analysis of data from optical measurements taken during half a year of weekly cruises in Murchison Bay, Lake Victoria, we present a three-component model for the absorption and a two-component model for the scattering of light in the UV and the visible regions of the solar spectrum along with tests of their ranges of validity. The three-component input to the model for absorption is the chlorophyll-a (Chl-a), total suspended materials concentrations, and yellow substance absorption, while the two-component input to the model for scattering is the Chl-a concentration and total suspended materials.

  15. Mapping dominant annual land cover from 2009 to 2013 across Victoria, Australia using satellite imagery

    PubMed Central

    Sheffield, Kathryn; Morse-McNabb, Elizabeth; Clark, Rob; Robson, Susan; Lewis, Hayden

    2015-01-01

    There is a demand for regularly updated, broad-scale, accurate land cover information in Victoria from multiple stakeholders. This paper documents the methods used to generate an annual dominant land cover (DLC) map for Victoria, Australia from 2009 to 2013. Vegetation phenology parameters derived from an annual time series of the Moderate Resolution Imaging Spectroradiometer Vegetation Indices 16-day 250 m (MOD13Q1) product were used to generate annual DLC maps, using a three-tiered hierarchical classification scheme. Classification accuracy at the broadest (primary) class level was over 91% for all years, while it ranged from 72 to 81% at the secondary class level. The most detailed class level (tertiary) had accuracy levels ranging from 61 to 68%. The approach used was able to accommodate variable climatic conditions, which had substantial impacts on vegetation growth patterns and agricultural production across the state between both regions and years. The production of an annual dataset with complete spatial coverage for Victoria provides a reliable base data set with an accuracy that is fit-for-purpose for many applications. PMID:26602009

  16. Genetic structure of pelagic and littoral cichlid fishes from Lake Victoria.

    PubMed

    Takeda, Miyuki; Kusumi, Junko; Mizoiri, Shinji; Aibara, Mitsuto; Mzighani, Semvua Isa; Sato, Tetsu; Terai, Yohey; Okada, Norihiro; Tachida, Hidenori

    2013-01-01

    The approximately 700 species of cichlids found in Lake Victoria in East Africa are thought to have evolved over a short period of time, and they represent one of the largest known examples of adaptive radiation. To understand the processes that are driving this spectacular radiation, we must determine the present genetic structure of these species and elucidate how this structure relates to the ecological conditions that caused their adaptation. We analyzed the genetic structure of two pelagic and seven littoral species sampled from the southeast area of Lake Victoria using sequences from the mtDNA control region and 12 microsatellite loci as markers. Using a Bayesian model-based clustering method to analyze the microsatellite data, we separated these nine species into four groups: one group composed of pelagic species and another three groups composed mainly of rocky-shore species. Furthermore, we found significant levels of genetic variation between species within each group at both marker loci using analysis of molecular variance (AMOVA), although the nine species often shared mtDNA haplotypes. We also found significant levels of genetic variation between populations within species. These results suggest that initial groupings, some of which appear to have been related to habitat differences, as well as divergence between species within groups took place among the cichlid species of Lake Victoria.

  17. A reinterpretation of geomorphological evidence for Glacial Lake Victoria, McMurdo Dry Valleys, Antarctica

    NASA Astrophysics Data System (ADS)

    McGowan, Hamish A.; Neil, David T.; Speirs, Johanna C.

    2014-03-01

    The largely snow and ice free McMurdo Dry Valleys of Antarctica are one of the coldest and driest locations on Earth. It has been proposed that during the Last Glacial Maximum (LGM) to the early Holocene large lakes up to 200 m deep and 100 km2 in area occupied these valleys. We present the first topographic survey of features reported to be shorelines from one such lake, Glacial Lake Victoria, in Victoria Valley. In combination with the analysis of laser altimetry data obtained from the NASA Airborne Topographic Mapper system and cosmogenic dating of granite boulders we show that the features previously thought to be shorelines are not horizontally or linearly continuous. Rather, we conclude that they are scars from ancient slope mass movement deposits. 10Be cosmogenic dating indicates that their formation is on timescales of at least 160 ka before present and not 20 ka as the LGM mega-lake hypothesis suggests. We conclude that the geomorphic features believed to be shorelines and which underpin the LGM mega-lake hypothesis in Victoria Valley are mass movement deposits and not lake shorelines. Our results support an emerging body of literature unable to find evidence to verify the McMurdo Dry Valleys LGM mega-lake hypothesis. Accordingly we suggest caution in invoking such significant landscape features in discussions of the environmental past of this unique region until such time as further research provides an unequivocal history of the region's geomorphic past.

  18. Mapping dominant annual land cover from 2009 to 2013 across Victoria, Australia using satellite imagery.

    PubMed

    Sheffield, Kathryn; Morse-McNabb, Elizabeth; Clark, Rob; Robson, Susan; Lewis, Hayden

    2015-11-24

    There is a demand for regularly updated, broad-scale, accurate land cover information in Victoria from multiple stakeholders. This paper documents the methods used to generate an annual dominant land cover (DLC) map for Victoria, Australia from 2009 to 2013. Vegetation phenology parameters derived from an annual time series of the Moderate Resolution Imaging Spectroradiometer Vegetation Indices 16-day 250 m (MOD13Q1) product were used to generate annual DLC maps, using a three-tiered hierarchical classification scheme. Classification accuracy at the broadest (primary) class level was over 91% for all years, while it ranged from 72 to 81% at the secondary class level. The most detailed class level (tertiary) had accuracy levels ranging from 61 to 68%. The approach used was able to accommodate variable climatic conditions, which had substantial impacts on vegetation growth patterns and agricultural production across the state between both regions and years. The production of an annual dataset with complete spatial coverage for Victoria provides a reliable base data set with an accuracy that is fit-for-purpose for many applications.

  19. Pervasive, tholeiitic refertilisation and heterogeneous metasomatism in Northern Victoria Land lithospheric mantle (Antarctica)

    NASA Astrophysics Data System (ADS)

    Pelorosso, Beatrice; Bonadiman, Costanza; Coltorti, Massimo; Faccini, Barbara; Melchiorre, Massimiliano; Ntaflos, Theodoros; Gregoire, Michel

    2016-04-01

    The petrology of peridotite xenoliths in the Cenozoic volcanics from Greene Point (Northern Victoria Land, Antarctica) provides new constraints on the characterisation of the lithospheric mantle beneath the West Antarctic Rift. Based on mineral major and trace element models, this mantle domain is proposed to represent a residuum after 10% and 20% partial melting. Moreover, melting models and isotopic results for Sr and Nd systematics highlight the substantial contribution of tholeiitic melts percolating through peridotites. Close correlation with trace element contents in clinopyroxene phenocrysts from Ferrar and Karoo tholeiites allows us to ascribe this refertilisation event to the Jurassic. This asthenospheric melt was also able to transfer a garnet signature to the Northern Victoria Land mantle segment. The rare presence of glass and secondary phases indicate that Greene Point xenoliths were heterogeneously affected by alkaline metasomatism, probably related to the West Antarctic Rift System opening; this has also been widely observed in other Northern Victoria Land localities (i.e., Baker Rocks). Temperature and fO2 were calculated (950 °C; Δlog fO2 (QFM), - 1.70 to - 0.39) at a fixed pressure of 15 kbar, confirming the tendency of the anhydrous Greene Point xenolith population to have higher equilibration temperatures and comparable redox conditions, compared to the nearby amphibole-bearing peridotites from Baker Rocks.

  20. Setting the Pace: New Insights into Central Pattern Generator Interactions in Box Jellyfish Swimming

    PubMed Central

    Stöckl, Anna Lisa; Petie, Ronald; Nilsson, Dan-Eric

    2011-01-01

    Central Pattern Generators (CPGs) produce rhythmic behaviour across all animal phyla. Cnidarians, which have a radially symmetric nervous system and pacemaker centres in multiples of four, provide an interesting comparison to bilaterian animals for studying the coordination between CPGs. The box jellyfish Tripedalia cystophora is remarkable among cnidarians due to its most elaborate visual system. Together with their ability to actively swim and steer, they use their visual system for multiple types of behaviour. The four swim CPGs are directly regulated by visual input. In this study, we addressed the question of how the four pacemaker centres of this radial symmetric cnidarian interact. We based our investigation on high speed camera observations of the timing of swim pulses of tethered animals (Tripedalia cystophora) with one or four rhopalia, under different simple light regimes. Additionally, we developed a numerical model of pacemaker interactions based on the inter pulse interval distribution of animals with one rhopalium. We showed that the model with fully resetting coupling and hyperpolarization of the pacemaker potential below baseline fitted the experimental data best. Moreover, the model of four swim pacemakers alone underscored the proportion of long inter pulse intervals (IPIs) considerably. Both in terms of the long IPIs as well as the overall swim pulse distribution, the simulation of two CPGs provided a better fit than that of four. We therefore suggest additional sources of pacemaker control than just visual input. We provide guidelines for future research on the physiological linkage of the cubozoan CPGs and show the insight from bilaterian CPG research, which show that pacemakers have to be studied in their bodily and nervous environment to capture all their functional features, are also manifest in cnidarians. PMID:22073288

  1. Jellyfish Lake, Palau: Regeneration of C, N, Si, and P in anoxic marine lake sediments

    USGS Publications Warehouse

    Lyons, W.B.; Lent, R.M.; Burnett, W.C.; Chin, P.; Landing, W.M.; Orem, W.H.; McArthur, J.M.

    1996-01-01

    Sediment cores from Jellyfish Lake were processed under an inert atmosphere and the pore waters extracted and analyzed for the following parameters: pH, titration alkalinity (TA), Cl-, H4SiO4, PO43-, NH4+, Ca2-, Mg2+, SO42-, and H2S. Additionally, in one set of pore-water samples (core 10), the ??13C of the ??CO2 was also determined. The TA, H4SiO4, PO43-, NH4+, and H2S increased with depth in the pore waters above anoxic bottom-water values. H2S values increased to 3.8 ??M. In one case, both H4SiO4 and PO43- concentrations increased to a maximum value and then decreased with depth, suggesting removal into solid phases. The H4SiO4 concentrations are equal to or greater than pore-water values observed in sediments underlying upwelling areas. PO43- concentrations are, in general, lower than pore-water values from terrigenous nearshore areas but higher than nearshore carbonate pore-water values from Florida Bay or Bermuda. The Ca2+, Cl-, and Mg2+: Cl- ratios show slight decreases in the top 15-20 cm, suggesting that authigenic carbonate may be forming. This suggestion is supported by the fact that the pore waters are saturated with respect to CaCO3 due to the very high TAs. The ??13C measurements of the pore-water ??CO2 are from a shorter core. These measurements reach their most negative concentration at 72 cm and then become slightly heavier. This change is accompanied by a decrease in TA, suggesting the onset of methanogenesis at this location in this core.

  2. Recombinant expression and solution structure of antimicrobial peptide aurelin from jellyfish Aurelia aurita

    SciTech Connect

    Shenkarev, Zakhar O.; Panteleev, Pavel V.; Balandin, Sergey V.; Finkina, Ekaterina I.; Arseniev, Alexander S.; Ovchinnikova, Tatiana V.

    2012-12-07

    Highlights: Black-Right-Pointing-Pointer Aurelin was overexpressed in Escherichia coli, and its spatial structure was studied by NMR. Black-Right-Pointing-Pointer Aurelin compact structure encloses helical regions cross-linked by three disulfide bonds. Black-Right-Pointing-Pointer Aurelin shows structural homology to the BgK and ShK toxins of sea anemones. Black-Right-Pointing-Pointer Aurelin binds to the anionic lipid vesicles, but does not interact with zwitterionic ones. Black-Right-Pointing-Pointer Aurelin binds to DPC micelle surface with moderate affinity via two helical regions. -- Abstract: Aurelin is a 40-residue cationic antimicrobial peptide isolated from the mezoglea of a scyphoid jellyfish Aurelia aurita. Aurelin and its {sup 15}N-labeled analogue were overexpressed in Escherichia coli and purified. Antimicrobial activity of the recombinant peptide was examined, and its spatial structure was studied by NMR spectroscopy. Aurelin represents a compact globule, enclosing one 3{sub 10}-helix and two {alpha}-helical regions cross-linked by three disulfide bonds. The peptide binds to anionic lipid (POPC/DOPG, 3:1) vesicles even at physiological salt concentration, it does not interact with zwitterionic (POPC) vesicles and interacts with the DPC micelle surface with moderate affinity via two {alpha}-helical regions. Although aurelin shows structural homology to the BgK and ShK toxins of sea anemones, its surface does not possess the 'functional dyad' required for the high-affinity interaction with the K{sup +}-channels. The obtained data permit to correlate the modest antibacterial properties and membrane activity of aurelin.

  3. Mitochondrial genome of the freshwater jellyfish Craspedacusta sowerbyi and phylogenetics of Medusozoa.

    PubMed

    Zou, Hong; Zhang, Jin; Li, Wenxiang; Wu, Shangong; Wang, Guitang

    2012-01-01

    The 17,922 base pairs (bp) nucleotide sequence of the linear mitochondrial DNA (mtDNA) molecule of the freshwater jellyfish Craspedacusta sowerbyi (Hydrozoa, Trachylina, Limnomedusae) has been determined. This sequence exhibits surprisingly low A+T content (57.1%), containing genes for 13 energy pathway proteins, a small and a large subunit rRNAs, and methionine and tryptophan tRNAs. Mitochondrial ancestral medusozoan gene order (AMGO) was found in the C. sowerbyi, as those found in Cubaia aphrodite (Hydrozoa, Trachylina, Limnomedusae), discomedusan Scyphozoa and Staurozoa. The genes of C. sowerbyi mtDNA are arranged in two clusters with opposite transcriptional polarities, whereby transcription proceeds toward the ends of the DNA molecule. Identical inverted terminal repeats (ITRs) flank the ends of the mitochondrial DNA molecule, a characteristic typical of medusozoans. In addition, two open reading frames (ORFs) of 354 and 1611 bp in length were found downstream of the large subunit rRNA gene, similar to the two ORFs of ORF314 and polB discovered in the linear mtDNA of C. aphrodite, discomedusan Scyphozoa and Staurozoa. Phylogenetic analyses of C. sowerbyi and other cnidarians were carried out based on both nucleotide and inferred amino acid sequences of the 13 mitochondrial energy pathway genes. Our working hypothesis supports the monophyletic Medusozoa being a sister group to Octocorallia (Cnidaria, Anthozoa). Within Medusozoa, the phylogenetic analysis suggests that Staurozoa may be the earliest diverging class and the sister group of all other medusozoans. Cubozoa and coronate Scyphozoa form a clade that is the sister group of Hydrozoa plus discomedusan Scyphozoa. Hydrozoa is the sister group of discomedusan Scyphozoa. Semaeostomeae is a paraphyletic clade with Rhizostomeae, while Limnomedusae (Trachylina) is the sister group of hydroidolinans and may be the earliest diverging lineage among Hydrozoa.

  4. [Molecular identification and detection of moon jellyfish (Aurelia sp.) based on partial sequencing of mitochondrial 16S rDNA and COI].

    PubMed

    Wang, Jian-Yan; Zhen, Yu; Wang, Guo-shan; Mi, Tie-Zhu; Yu, Zhi-gang

    2013-03-01

    Taking the moon jellyfish Aurelia sp. commonly found in our coastal sea areas as test object, its genome DNA was extracted, the partial sequences of mt-16S rDNA (650 bp) and mt-COI (709 bp) were PCR-amplified, and, after purification, cloning, and sequencing, the sequences obtained were BLASTn-analyzed. The sequences of greater difference with those of the other jellyfish were chosen, and eight specific primers for the mt-16S rDNA and mt-COI of Aurelia sp. were designed, respectively. The specificity test indicated that the primer AS3 for the mt-16S rDNA and the primer AC3 for the mt-COI were excellent in rapidly detecting the target jellyfish from Rhopilema esculentum, Nemopilema nomurai, Cyanea nozakii, Acromitus sp., and Aurelia sp., and thus, the techniques for the molecular identification and detection of moon jellyfish were preliminarily established, which could get rid of the limitations in classical morphological identification of Aurelia sp. , being able to find the Aurelia sp. in the samples more quickly and accurately.

  5. Isolation and characterization of a novel protein toxin from the Hawaiian box jellyfish (sea wasp) Carybdea alata.

    PubMed

    Nagai, H; Takuwa, K; Nakao, M; Sakamoto, B; Crow, G L; Nakajima, T

    2000-08-28

    The box jellyfish (sea wasp) Carybdea alata Reynaud, 1830 (Cubozoa) is distributed widely in the tropics. The sting of C. alata causes severe pain and cutaneous inflammation in humans. We successfully isolated C. alata toxin-A (CaTX-A, 43 kDa) and -B (CaTX-B, 45 kDa) for the first time from the tentacle of C. alata collected at a site along the Hawaiian shore. The experimental results showed that CaTX-A, but not CaTX-B, is present in the nematocyst, the organ responsible for stinging. Both CaTX-A and -B showed potent hemolytic activity, with CaTX-A being lethally toxic to crayfish when administered via intraperitoneal injection. Furthermore, we sequenced the cDNA encoding CaTX-A. The deduced amino acid sequence of CaTX-A (463 amino acids) showed 43.7% homology to Carybdea rastoni toxins (CrTXs) but not with any other known proteins. Therefore, these jellyfish toxins potentially represent a novel class of bioactive proteins. Secondary structure analysis of CaTX-A and CrTXs suggested the presence of amphiphilic alpha-helices, which are also seen in several known hemolytic or cytolytic protein toxins, including peptide toxins.

  6. Screening of extraction methods for glycoproteins from jellyfish ( Rhopilema esculentum) oral-arms by high performance liquid chromatography

    NASA Astrophysics Data System (ADS)

    Ren, Guoyan; Li, Bafang; Zhao, Xue; Zhuang, Yongliang; Yan, Mingyan; Hou, Hu; Zhang, Xiukun; Chen, Li

    2009-03-01

    In order to select an optimum extraction method for the target glycoprotein (TGP) from jellyfish ( Rhopilema esculentum) oral-arms, a high performance liquid chromatography (HPLC)-assay for the determination of the TGP was developed. Purified target glycoprotein was taken as a standard glycoprotein. The results showed that the calibration curves for peak area plotted against concentration for TGP were linear ( r = 0.9984, y = 4.5895 x+47.601) over concentrations ranging from 50 to 400 mgL-1. The mean extraction recovery was 97.84% (CV2.60%). The fractions containing TGP were isolated from jellyfish ( R. esculentum) oral-arms by four extraction methods: 1) water extraction (WE), 2) phosphate buffer solution (PBS) extraction (PE), 3) ultrasound-assisted water extraction (UA-WE), 4) ultrasound-assisted PBS extraction (UA-PE). The lyophilized extract was dissolved in Milli-Q water and analyzed directly on a short TSK-GEL G4000PWXL (7.8 mm×300 mm) column. Our results indicated that the UA-PE method was the optimum extraction method selected by HPLC.

  7. Cloning a Chymotrypsin-Like 1 (CTRL-1) Protease cDNA from the Jellyfish Nemopilema nomurai

    PubMed Central

    Heo, Yunwi; Kwon, Young Chul; Bae, Seong Kyeong; Hwang, Duhyeon; Yang, Hye Ryeon; Choudhary, Indu; Lee, Hyunkyoung; Yum, Seungshic; Shin, Kyoungsoon; Yoon, Won Duk; Kang, Changkeun; Kim, Euikyung

    2016-01-01

    An enzyme in a nematocyst extract of the Nemopilema nomurai jellyfish, caught off the coast of the Republic of Korea, catalyzed the cleavage of chymotrypsin substrate in an amidolytic kinetic assay, and this activity was inhibited by the serine protease inhibitor, phenylmethanesulfonyl fluoride. We isolated the full-length cDNA sequence of this enzyme, which contains 850 nucleotides, with an open reading frame of 801 encoding 266 amino acids. A blast analysis of the deduced amino acid sequence showed 41% identity with human chymotrypsin-like (CTRL) and the CTRL-1 precursor. Therefore, we designated this enzyme N. nomurai CTRL-1. The primary structure of N. nomurai CTRL-1 includes a leader peptide and a highly conserved catalytic triad of His69, Asp117, and Ser216. The disulfide bonds of chymotrypsin and the substrate-binding sites are highly conserved compared with the CTRLs of other species, including mammalian species. Nemopilema nomurai CTRL-1 is evolutionarily more closely related to Actinopterygii than to Scyphozoan (Aurelia aurita) or Hydrozoan (Hydra vulgaris). The N. nomurai CTRL1 was amplified from the genomic DNA with PCR using specific primers designed based on the full-length cDNA, and then sequenced. The N. nomurai CTRL1 gene contains 2434 nucleotides and four distinct exons. The 5′ donor splice (GT) and 3′ acceptor splice sequences (AG) are wholly conserved. This is the first report of the CTRL1 gene and cDNA structures in the jellyfish N. nomurai. PMID:27399771

  8. Abrupt Changes in the Marmara Pelagic Ecosystem during the recent jellyfish Liriope tetraphylla invasion and mucilage events

    NASA Astrophysics Data System (ADS)

    Erkan Kideys, Ahmet; Yüksek, Ahsen; Sur, Halil Ibrahim

    2013-04-01

    In this study, meteorological and hydrographical conditions as well as chemical and biological parameters have been examined for the period 2005-2009 to determine the impact and cause of the massive mucilage phenomenon observed in the Sea of Marmara in October 2007. Results showed that there is a decrease pattern in chl concentration as well as both phytoplankton and zooplankton abundances from August till October in 2007 whilst the jellyfish Liriope tetraphylla had bloom levels. This period coincided with the maximum intensity of pelagic fishing throughout the years. Nitrogen/phosphate ratio increased prior to the mucilage formation. Invasive Liriope tetraphylla abundance increased exponentially in August and died in masses as a result of starvation and meteorological / oceanographic conditions. In October, following the mucilage matter production another new species for the region Gonyaulax fragilis was observed in high abundance through the basin. It is worthy to note that during basin wide samplings conducted in the Sea of Marmara in both 2005 and 2006, high abundances of Liriope tetraphylla have been detected particularly at the northern parts where no mucilage event was observed. We suggest that overfishing in the Sea of Marmara provided a ground for the establishment of the invasive jellyfish and accompanying mucilage event was due to by synergic combinations of several factors.

  9. Macrobenthic community structure and species composition in the Yellow Sea and East China Sea in jellyfish bloom

    NASA Astrophysics Data System (ADS)

    Peng, Songyao; Li, Xinzheng; Wang, Hongfa; Zhang, Baolin

    2014-05-01

    To understand the characteristics of macrobenthic structures and the relationship between environment and benthic assemblages in jellyfish bloom, we studied the macrobenthos and related environmental factors in the coastal waters of the Yellow Sea and East China Sea. Data were collected during two seasonal cruises in April and August of 2011, and analyzed with multivariate statistical methods. Up to 306 macrobenthic species were registered from the research areas, including 115 species of Polychaeta, 78 of Crustacea, 61 of Mollusca, 30 of Echinodermata, and 22 of other groups. Nine polychaete species occurred at frequencies higher than 25% from the sampling stations: Lumbrineris longifolia, Notomastus latericeus, Ninöe palmata, Ophelina acuminata, Nephtys oligobranchia, Onuphis geophiliformis, Glycera chirori, Terebellides stroemii, and Aricidea fragilis. Both the average biomass and abundance of macrobenthos are higher in August (23.8 g/m2 and 237.7 ind./m2) than those in April (11.3 g/m2 and 128 ind./m2); the dissimilarity of macrobenthic structures among stations is as high as 70%. In terms of the dissimilarity values, we divided the stations into four clusters in spring and eight in summer. The ABC curve shows that the macrofauna communities in high jellyfish abundance were not changed. Canonical correspondence analysis showed that depth, temperature, median grain size, total organic carbon of sediment and total nitrogen in sediment were important factors affecting the macrozoobenthic community in the study area.

  10. New family of allomorphic jellyfishes, Drymonematidae (Scyphozoa, Discomedusae), emphasizes evolution in the functional morphology and trophic ecology of gelatinous zooplankton.

    PubMed

    Bayha, Keith M; Dawson, Michael N

    2010-12-01

    Molecular analyses have revealed many cryptic species in the oceans, often permitting small morphological differences to be recognized as diagnosing species, but less commonly leading to consideration of cryptic ecology. Here, based on analyses of three nuclear DNA sequence markers (ribosomal 18S, 28S, and internal transcribed spacer 1 [ITS1]), two mitochondrial DNA markers (cytochrome c oxidase subunit I [COI] and ribosomal 16S), and 55 morphological features, we revise the classification of the enigmatic jellyfish genus Drymonema. We describe a new scyphozoan family, Drymonematidae, elevating the previous subfamily Drymonemidae to accommodate three species: the type species D. dalmatinum from the Mediterranean region, for which we identify a neotype; the western South Atlantic species D. gorgo; and a new species, D. larsoni from the western Atlantic and Caribbean, which also is described here. This revision emphasizes the remarkable morphological disparity of Drymonematidae from all other scyphomedusae, including allometric growth of the bell margin distal of the rhopalia, an annular zone of tentacles on the subumbrella, and ontogenetic loss of gastric filaments. Anatomical innovations are likely functionally related to predatory specialization on large gelatinous zooplankton, most notably the phylogenetically younger moon jellyfish Aurelia, indicating evolution of the feeding niche in Drymonematidae. This family-level revision contributes to the growing body of evidence that scyphomedusae are far more taxonomically rich, their biogeography is a more detailed mosaic, and their phenotypes are more nuanced than traditionally thought. Ecological and evolutionary responses to environmental change, past or future, are likely to be commensurately diverse.

  11. Predicting aqueous copper and zinc accumulation in the upside-down jellyfish Cassiopea maremetens through the use of biokinetic models.

    PubMed

    Templeman, Michelle A; Kingsford, Michael J

    2015-07-01

    Jellyfish have a demonstrated capability to accumulate metals within their tissues, but to date, there have been no quantitative assessments of accumulation and retention rates and patterns. Bioconcentration patterns of copper and zinc in the upside-down jellyfish Cassiopea maremetens were modelled over a 28-day study (14 days exposure followed by 14 days clearance). C. maremetens accumulated copper over 14 days with the maximum calculated copper concentrations at 33.78 μg g(-1) dry weight and bioconcentrated to 99 times water concentrations. Zinc was also accumulated during the exposure period and retained for longer. The maximum theoretical zinc concentration was 125.1 μg g(-1) dry weight with a kinetic bioconcentration factor of 104. The patterns of uptake and retention were different between the elements. The use of kinetic models provided adequate predictions of aqueous metal uptake and retention in C. maremetens. This species has the capacity to very rapidly absorb measurable metals from short-term water-metal exposure.

  12. Nitrogen and phosphorus budget of a polyculture system of sea cucumber ( Apostichopus japonicus), jellyfish ( Rhopilema esculenta) and shrimp ( Fenneropenaeus chinensis)

    NASA Astrophysics Data System (ADS)

    Li, Junwei; Dong, Shuanglin; Gao, Qinfeng; Zhu, Changbo

    2014-06-01

    The nitrogen (N) and phosphorus (P) budget and the ecological efficiency of a polyculture system of sea cucumber ( Apostichopus japonicus), jellyfish ( Rhopilema esculenta) and shrimp ( Fenneropenaeus chinensis) were studied in a cofferdam, 120.2 ha in size. The nutrients were supplied by spring tide inflow. In total, 139600 kg N yr-1 and 9730 kg P yr-1 input to the system; while 118900 kg N yr-1 and 2840 kg P yr-1 outflowed from the system concurrently, thus the outflow was 85.7% (N) and 29.2% (P) of inflow. The production of N and P was 889.5 kg yr-1 and 49.28 kg yr-1 (sea cucumber) and 204 kg yr-1 and 18.03 kg yr-1 (jellyfish and shrimp), respectively. The utilization rate of N and P by polycultured animals was 7.8‰ and 6.9‰, respectively, 21.9% and 38% higher than that of monocultured sea cucumber. Our results indicated that the polyculture system was an efficient culture system of animals and a remediation system of coastal environment as well; it scavenged 14.3% and 70.8% of N and P, respectively. Such an ecological efficiency may be improved further by increasing either the stocking density or the size of sea cucumber or both.

  13. Use of the A. victoria green fluorescent protein to study protein dynamics in vivo.

    PubMed

    Kahana, J A; Silver, P A

    2001-05-01

    Fluorescent molecules serve as valuable tools for the detection of numerous biochemical phenomena and have been employed for protein localization, quantitation of gene expression, detection of nucleic acids, cell sorting and determination of chemical concentrations. However, the use of such techniques generally requires significant nonphysiological perturbations to the biological system being studied; therefore, they are not always appropriate for the observation of dynamic phenomena. Green fluorescent protein (GFP), cloned from jellyfish, has been used to overcome many of these problems. It is a small, extremely stable fluorescent protein that has been successfully expressed and detected in a wide variety of organisms, both in intact form and fused to other proteins. This overview unit describes the use of this proteinaceous fluorophore for in vivo observation of cellular phenomena.

  14. High prevalence of non-synonymous substitutions in mtDNA of cichlid fishes from Lake Victoria.

    PubMed

    Shirai, Kazumasa; Inomata, Nobuyuki; Mizoiri, Shinji; Aibara, Mitsuto; Terai, Yohey; Okada, Norihiro; Tachida, Hidenori

    2014-12-01

    When a population size is reduced, genetic drift may fix slightly deleterious mutations, and an increase in nonsynonymous substitution is expected. It has been suggested that past aridity has seriously affected and decreased the populations of cichlid fishes in Lake Victoria, while geographical studies have shown that the water levels in Lake Tanganyika and Lake Malawi have remained fairly constant. The comparably stable environments in the latter two lakes might have kept the populations of cichlid fishes large enough to remove slightly deleterious mutations. The difference in the stability of cichlid fish population sizes between Lake Victoria and the Lakes Tanganyika and Malawi is expected to have caused differences in the nonsynonymous/synonymous ratio, ω (=dN/dS), of the evolutionary rate. Here, we estimated ω and compared it between the cichlids of the three lakes for 13 mitochondrial protein-coding genes using maximum likelihood methods. We found that the lineages of the cichlids in Lake Victoria had a significantly higher ω for several mitochondrial loci. Moreover, positive selection was indicated for several codons in the mtDNA of the Lake Victoria cichlid lineage. Our results indicate that both adaptive and slightly deleterious molecular evolution has taken place in the Lake Victoria cichlids' mtDNA genes, whose nonsynonymous sites are generally conserved.

  15. Population-structure and genetic diversity in a haplochromine cichlid fish [corrected] of a satellite lake of Lake Victoria.

    PubMed

    Abila, Romulus; Barluenga, Marta; Engelken, Johannes; Meyer, Axel; Salzburger, Walter

    2004-09-01

    The approximately 500 species of the cichlid fish species flock of Lake Victoria, East Africa, have evolved in a record-setting 100,000 years and represent one of the largest adaptive radiations. We examined the population structure of the endangered cichlid species Xystichromis phytophagus from Lake Kanyaboli, a satellite lake to Lake Victoria in the Kenyan Yala wetlands. Two sets of molecular markers were analysed--sequences of the mitochondrial control region as well as six microsatellite loci--and revealed surprisingly high levels of genetic variability in this species. Mitochondrial DNA sequences failed to detect population structuring among the three sample populations. A model-based population assignment test based on microsatellite data revealed that the three populations most probably aggregate into a larger panmictic population. However, values of population pairwise FST indicated moderate levels of genetic differentiation for one population. Eleven distinct mitochondrial haplotypes were found among 205 specimens of X. phytophagus, a relatively high number compared to the total number of 54 haplotypes that were recovered from hundreds of specimens of the entire cichlid species flock of Lake Victoria. Most of the X. phytophagus mitochondrial DNA haplotypes were absent from the main Lake Victoria, corroborating the putative importance of satellite lakes as refugia for haplochromine cichlids that went extinct from the main lake in the last decades and possibly during the Late Pleistocene desiccation of Lake Victoria.

  16. Glacial geomorphology of the Victoria Valley System, Ross Sea Region, Antarctica

    NASA Astrophysics Data System (ADS)

    Bockheim, James G.; McLeod, Malcolm

    2013-07-01

    During the 2011-2012 austral summer, we had the opportunity to verify a surficial geology map prepared nearly 50 years ago for the Victoria Valley system (VVS), the largest of the McMurdo Dry Valleys. We used high-resolution landsat images and a digital elevation model to identify landforms and prepare detailed maps of each of the five valleys in the VVS, including lateral and end moraines, rock glaciers, gelifluction sheets, gravel ripples, and hummocky and ice-cored drifts. Our mapping suggests that the Bull drift is less extensive than previously thought, attains a maximum elevation of ~ 750 m in Balham and Barwick Valleys and the upper Bull Pass region, and does not occur in McKelvey Valley. We found Insel drift to 850 m elevation in eastern McKelvey Valley and upper Bull Pass and were able to trace Insel drift down Bull Pass where it becomes Peleus drift in Wright Valley. The Victoria Lower Glacier likely responded to grounding of ice in the Ross Embayment and was out-of-phase with alpine glaciers elsewhere in the VVS. We amplified and quantified Calkin's relative chronology and provide here our multiple-parameter relative chronology for the McMurdo Dry Valleys that is based on surface-boulder weathering, soil weathering, salt stage, degree of development of the desert pavement, and form of patterned ground. Except for Victoria Lower Valley, we correlate Packard drift with Taylor II drift (ca., 120 ka), Vida drift with Taylor III drift (ca., 300 ka), Bull drift with Taylor IVb drift (2.7-3.5 Ma, and Insel drift with Peleus drift (> 3.7 Ma, < 5.4 Ma). The lack of a strong correlation between soil salt stage and depth of visible salts with elevation leads us to question whether a high-level lake (ca., 200 m deep) existed in the VVS during the early Holocene.

  17. Metals in Nile perch (Lates niloticus) and suspended particulate matter from Lake Victoria, Tanzania.

    PubMed

    Machiwa, John F

    2005-01-01

    A study was conducted to assess the levels of pollutant metals in suspended particulate matter and Nile perch from Lake Victoria. The metals in particulate matter were determined to ascertain their concentrations at the base of the food chain. Nile perch samples were collected in September 2003 from five major fish processing factories at the shores of Lake Victoria in Mwanza and Musoma. The concentrations of total Hg, Pb, Cd, and Cu were generally low in particulate matter and in most locations were close to or below their limits of detection. The concentrations of Zn were high in suspended particulate matter, the highest being 219.4 +/- 153.0 microg L(-1) found in particulate matter from Nungwe Bay in the southern part of Lake Victoria. Nile perch generally contained low levels of heavy metals; the range for Pb was <0.01-0.08 microg g(-1) ww, Cd was <0.001-0.04 microg g(-1) ww, Cu was 0.01-0.97 microg g(-1) ww, and Zn was <0.01-18.94 microg g(-1) ww. The concentration of total mercury ranged between 31.0 and 684.2 ng g(-1) ww; generally, it was below the Food and Agriculture Organization of the United Nations/World Health Organization (1000 ng total Hg g(-1) ww for piscivorous fish species) maximum allowable level. Indeed, all Nile perch samples that weighed less than 10 kg had less than 200 ng total Hg g(-1) ww and therefore are safe for regular consumption by at-risk groups such as children and pregnant women. Levels of mercury and other heavy metals in Nile perch at present is, therefore, not a severe environmental issue; however, urgent regulatory measures should be taken to minimize metal input into the lake to maintain the current levels in the fish.