Cyrilia sp. (Apicomplexa: Haemogregarinidae) in the Amazonian freshwater stingray Potamotrygon wallacei (cururu stingray) in different hydrological phases of the Rio Negro.

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Oliveira, A T; Araújo, M L G; Pantoja-Lima, J; Aride, P H R; Tavares-Dias, M; Brinn, R P; Marcon, J L

2017-01-01

Intraerythrocytic parasites are frequently found in fish, including elasmobranchs. The Amazonian rivers present well defined annual hydrological cycles that results in drastic modifications of the environmental conditions with deep implications in the life cycle of the whole associated biota in those fluvial systems. The freshwater stingray Potamotrygon wallacei (stingray cururu) is a new species restricted to the Middle Rio Negro basin and it is subject to strong alterations in their natural habitats (igapós) a result of the constant variations in the water level of Rio Negro. This work demonstrates the occurrence of intraerythrocytic parasite Cyrilia sp. in this stingray species. Additionally, the prevalence and quantification of hemoparasites in different phases of Rio Negro were also established. Field sampling was carried in the Archipelago of Mariuá, Middle Rio Negro, involving different stages of the water cycle. The intraerythrocytic parasites were quantified by direct counting in blood smears using a total counting of 2000 erythrocytes in each blood smear. The presence of parasites intraerythrocytic generates changes in the morphology of blood cell. The largest amount of the hemoparasites was recorded in the drought period. We observed a decreasing tendency in the number of parasites in the blood between the drought periods and inundation. We concluded that the level of Negro River influences the incidence of intraerythrocytic parasites in the cururu stingray and the drought represents the period of larger susceptibility to the infestation.

Cyrilia sp. (Apicomplexa: Haemogregarinidae in the Amazonian freshwater stingray Potamotrygon wallacei (cururu stingray in different hydrological phases of the Rio Negro

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A. T. Oliveira

Full Text Available Abstract Intraerythrocytic parasites are frequently found in fish, including elasmobranchs. The Amazonian rivers present well defined annual hydrological cycles that results in drastic modifications of the environmental conditions with deep implications in the life cycle of the whole associated biota in those fluvial systems. The freshwater stingray Potamotrygon wallacei (stingray cururu is a new species restricted to the Middle Rio Negro basin and it is subject to strong alterations in their natural habitats (igapós a result of the constant variations in the water level of Rio Negro. This work demonstrates the occurrence of intraerythrocytic parasite Cyrilia sp. in this stingray species. Additionally, the prevalence and quantification of hemoparasites in different phases of Rio Negro were also established. Field sampling was carried in the Archipelago of Mariuá, Middle Rio Negro, involving different stages of the water cycle. The intraerythrocytic parasites were quantified by direct counting in blood smears using a total counting of 2000 erythrocytes in each blood smear. The presence of parasites intraerythrocytic generates changes in the morphology of blood cell. The largest amount of the hemoparasites was recorded in the drought period. We observed a decreasing tendency in the number of parasites in the blood between the drought periods and inundation. We concluded that the level of Negro River influences the incidence of intraerythrocytic parasites in the cururu stingray and the drought represents the period of larger susceptibility to the infestation.

Maternal transfer of organohalogenated compounds in sharks and stingrays.

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Weijs, Liesbeth; Briels, Nathalie; Adams, Douglas H; Lepoint, Gilles; Das, Krishna; Blust, Ronny; Covaci, Adrian

2015-03-15

Elasmobranchs can bioaccumulate considerable amounts of persistent organic pollutants (POPs) and utilize several reproductive strategies thereby influencing maternal transfer of contaminants. This study provides preliminary data on the POP transfer from pregnant females to offspring of three species (Atlantic stingrays, bonnethead, blacktip sharks) with different reproduction modes (aplacental, placental viviparity). Polychlorinated biphenyl (PCB) levels were generally higher than any other POPs. Stingrays and blacktip shark embryos contained the lowest POP concentrations while bonnetheads and the blacktip adult female had the highest concentrations. Results suggest that POPs are more readily transferred from the mother to the embryo compared to what is transferred to ova in stingrays. Statistically significant differences in levels of selected POPs were found between embryos from the left and right uterus within the same litter as well as between female and male embryos within the same litter for bonnetheads, but not for the blacktip sharks. Copyright © 2015 Elsevier Ltd. All rights reserved.

Are you positive? Electric dipole polarity discrimination in the yellow stingray, Urobatis jamaicensis.

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Siciliano, Avery M; Kajiura, Stephen M; Long, John H; Porter, Marianne E

2013-10-01

It is well established that elasmobranchs can detect dipole electric fields. However, it is unclear whether they can discriminate between the anode and cathode. To investigate this subject, we employed a behavioral assay to determine the discriminatory ability of the yellow stingray, Urobatis jamaicensis. We conditioned stingrays with food rewards to bite either the anode (n=5) or the cathode (n=6) of a direct-current dipole located on the floor of an experimental tank. All individuals successfully performed the task after 18 to 22 days. Stingrays were then tested in experimental sessions when they were rewarded only after they identified the correct pole. Stingrays successfully discriminated between the poles at a rate greater than chance, ranging among individuals from a mean of 66% to 93% correct. During experimental sessions, stingrays conditioned to distinguish the anode performed similarly to those conditioned to distinguish the cathode. We hypothesize that the ability to discriminate anode from cathode is physiologically encoded, but its utility in providing spatial information under natural conditions remains to be demonstrated. The ability to discriminate polarity may eliminate ambiguity in induction-based magnetoreception and facilitate navigation with respect to the geomagnetic field.

The putative mechanism of Na(+) absorption in euryhaline elasmobranchs exists in the gills of a stenohaline marine elasmobranch, Squalus acanthias.

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Choe, Keith P; Edwards, Susan L; Claiborne, James B; Evans, David H

2007-02-01

We recently cloned an NHE3 orthologue from the gills of the euryhaline Atlantic stingray (Dasyatis sabina), and generated a stingray NHE3 antibody to unequivocally localize the exchanger to the apical side of epithelial cells that are rich with Na(+)/K(+)-ATPase (A MRC). We also demonstrated an increase in NHE3 expression when stingrays are in fresh water, suggesting that NHE3 is responsible for active Na(+) absorption. However, the vast majority of elasmobranchs are only found in marine environments. In the current study, immunohistochemistry with the stingray NHE3 antibody was used to localize the exchanger in the gills of the stenohaline marine spiny dogfish shark (Squalus acanthias). NHE3 immunoreactivity was confined to the apical side of cells with basolateral Na(+)/K(+)-ATPase and was excluded from cells with high levels of vacuolar H(+)-ATPase. Western blots detected a single protein of 88 kDa in dogfish gills, the same size as NHE3 in stingrays and mammals. These immunological data demonstrate that the putative cell type responsible for active Na(+) absorption in euryhaline elasmobranchs is also present in stenohaline marine elasmobranchs, and suggest that the inability of most elasmobranchs to survive in fresh water is not due to a lack of the gill ion transporters for Na(+) absorption.

[Management of bluespotted stingray injuries in Djibouti from July 2008 to July 2009].

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Aigle, L; Lions, C; Mottier, F; Ollivier, L

2010-06-01

Although stingray injuries have always been frequent in the Republic of Djibouti, it was not until July 2008 that the Bouffard Hospital developed a standardised management protocol. The purpose of this report is to describe that protocol and evaluate its impact on the outcome of stingray injuries based on a prospective study for the period between July 2008 and July 2009. During the study period, 12 stingray stings were treated. The treatment protocol that is based on a multidisciplinary approach involving the intensivist, anaesthesiologist, and surgeon achieved wound healing within one month. This outcome contrasts with previous publications that have generally described longer healing times with frequent infectious complications.

Magnetic field discrimination, learning, and memory in the yellow stingray (Urobatis jamaicensis).

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Newton, Kyle C; Kajiura, Stephen M

2017-07-01

Elasmobranch fishes (sharks, skates, and rays) have been hypothesized to use the geomagnetic field as a cue for orienting and navigating across a wide range of spatial scales. Magnetoreception has been demonstrated in many invertebrate and vertebrate taxa, including elasmobranchs, but this sensory modality and the cognitive abilities of cartilaginous fishes are poorly studied. Wild caught yellow stingrays, Urobatis jamaicensis (N = 8), underwent conditioning to associate a magnetic stimulus with a food reward in order to elicit foraging behaviors. Behavioral conditioning consisted of burying magnets and non-magnetic controls at random locations within a test arena and feeding stingrays as they passed over the hidden magnets. The location of the magnets and controls was changed for each trial, and all confounding sensory cues were eliminated. The stingrays learned to discriminate the magnetic stimuli within a mean of 12.6 ± 0.7 SE training sessions of four trials per session. Memory probes were conducted at intervals between 90 and 180 days post-learning criterion, and six of eight stingrays completed the probes with a ≥75% success rate and minimum latency to complete the task. These results show the fastest rate of learning and longest memory window for any batoid (skate or ray) to date. This study demonstrates that yellow stingrays, and possibly other elasmobranchs, can use a magnetic stimulus as a geographic marker for the location of resources and is an important step toward understanding whether these fishes use geomagnetic cues during spatial navigation tasks in the natural environment.

Injuries caused by freshwater stingrays in the Tapajós River Basin: a clinical and sociodemographic study

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Paulo Afonso Martins Abati

Full Text Available Abstract INTRODUCTION Freshwater stingray envenomations are an important cause of morbidity in riverine populations living in various regions of Brazil. The sequelae include temporary or permanent disability. This study aimed to identify sociodemographic, clinical, and therapeutic aspects related to stingray injuries in such populations. METHODS This cross-sectional study was conducted in the Extractive Reserve of Tapajos-Arapiuns, located in the municipalities of Santarém and Aveiro (Pará State. A convenience sample comprising 300 local adults was used to obtain data by means of a questionnaire/ interview. RESULTS Overall, 19 (6.3% participants reported having sustained a stingray injury in the 12 months prior to the study. All 19 were injured either while fishing (n=13 [68.4%] or engaging in other riverine activities. Most injuries [n=14 (73.7%] occurred from September through November, and most injured respondents [n=15 (78.9%] reported seeing stingrays at beaches. Severe pain and the appearance of ulcers in the later stages of envenomation were described by 18 (94.7% and 12 (63.2% participants, respectively. CONCLUSIONS Freshwater stingray injuries, which should be considered occupational injuries, are common in the study area, especially in places like beaches or in the lakes that form during the dry season, when stingrays are routinely observed. A significant proportion of respondents was unaware of the correct first aid measures and had insufficient resources to treat the complications of these injuries in the locality where they reside. Interactive activities involving local residents - such as lectures and the distribution of simple pamphlets providing information about stingray injuries - are needed.

Evolutionary bottlenecks in brackish water habitats drive the colonization of fresh water by stingrays.

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Kirchhoff, K N; Hauffe, T; Stelbrink, B; Albrecht, C; Wilke, T

2017-08-01

Species richness in freshwater bony fishes depends on two main processes: the transition into and the diversification within freshwater habitats. In contrast to bony fishes, only few cartilaginous fishes, mostly stingrays (Myliobatoidei), were able to colonize fresh water. Respective transition processes have been mainly assessed from a physiological and morphological perspective, indicating that the freshwater lifestyle is strongly limited by the ability to perform osmoregulatory adaptations. However, the transition history and the effect of physiological constraints on the diversification in stingrays remain poorly understood. Herein, we estimated the geographic pathways of freshwater colonization and inferred the mode of habitat transitions. Further, we assessed habitat-related speciation rates in a time-calibrated phylogenetic framework to understand factors driving the transition of stingrays into and the diversification within fresh water. Using South American and Southeast Asian freshwater taxa as model organisms, we found one independent freshwater colonization event by stingrays in South America and at least three in Southeast Asia. We revealed that vicariant processes most likely caused freshwater transition during the time of major marine incursions. The habitat transition rates indicate that brackish water species switch preferably back into marine than forth into freshwater habitats. Moreover, our results showed significantly lower diversification rates in brackish water lineages, whereas freshwater and marine lineages exhibit similar rates. Thus, brackish water habitats may have functioned as evolutionary bottlenecks for the colonization of fresh water by stingrays, probably because of the higher variability of environmental conditions in brackish water. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

Diet reconstruction and resource partitioning of a Caribbean marine mesopredator using stable isotope bayesian modelling.

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Alexander Tilley

Full Text Available The trophic ecology of epibenthic mesopredators is not well understood in terms of prey partitioning with sympatric elasmobranchs or their effects on prey communities, yet the importance of omnivores in community trophic dynamics is being increasingly realised. This study used stable isotope analysis of (15N and (13C to model diet composition of wild southern stingrays Dasyatis americana and compare trophic niche space to nurse sharks Ginglymostoma cirratum and Caribbean reef sharks Carcharhinus perezi on Glovers Reef Atoll, Belize. Bayesian stable isotope mixing models were used to investigate prey choice as well as viable Diet-Tissue Discrimination Factors for use with stingrays. Stingray δ(15N values showed the greatest variation and a positive relationship with size, with an isotopic niche width approximately twice that of sympatric species. Shark species exhibited comparatively restricted δ(15N values and greater δ(13C variation, with very little overlap of stingray niche space. Mixing models suggest bivalves and annelids are proportionally more important prey in the stingray diet than crustaceans and teleosts at Glovers Reef, in contrast to all but one published diet study using stomach contents from other locations. Incorporating gut contents information from the literature, we suggest diet-tissue discrimination factors values of Δ(15N ≈ 2.7‰ and Δ(13C ≈ 0.9‰ for stingrays in the absence of validation experiments. The wide trophic niche and lower trophic level exhibited by stingrays compared to sympatric sharks supports their putative role as important base stabilisers in benthic systems, with the potential to absorb trophic perturbations through numerous opportunistic prey interactions.

Diet reconstruction and resource partitioning of a Caribbean marine mesopredator using stable isotope bayesian modelling.

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Tilley, Alexander; López-Angarita, Juliana; Turner, John R

2013-01-01

The trophic ecology of epibenthic mesopredators is not well understood in terms of prey partitioning with sympatric elasmobranchs or their effects on prey communities, yet the importance of omnivores in community trophic dynamics is being increasingly realised. This study used stable isotope analysis of (15)N and (13)C to model diet composition of wild southern stingrays Dasyatis americana and compare trophic niche space to nurse sharks Ginglymostoma cirratum and Caribbean reef sharks Carcharhinus perezi on Glovers Reef Atoll, Belize. Bayesian stable isotope mixing models were used to investigate prey choice as well as viable Diet-Tissue Discrimination Factors for use with stingrays. Stingray δ(15)N values showed the greatest variation and a positive relationship with size, with an isotopic niche width approximately twice that of sympatric species. Shark species exhibited comparatively restricted δ(15)N values and greater δ(13)C variation, with very little overlap of stingray niche space. Mixing models suggest bivalves and annelids are proportionally more important prey in the stingray diet than crustaceans and teleosts at Glovers Reef, in contrast to all but one published diet study using stomach contents from other locations. Incorporating gut contents information from the literature, we suggest diet-tissue discrimination factors values of Δ(15)N ≈ 2.7‰ and Δ(13)C ≈ 0.9‰ for stingrays in the absence of validation experiments. The wide trophic niche and lower trophic level exhibited by stingrays compared to sympatric sharks supports their putative role as important base stabilisers in benthic systems, with the potential to absorb trophic perturbations through numerous opportunistic prey interactions.

The toxinology of stingrays

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Gholamhossein Mohebbi

2016-09-01

Full Text Available Background: Stingrays belong to Chondrichthyes class.They live in freshwaters and oceans all over the world. They have venomous spines next to the root of the tail. Their barbed stingers covered with secretory cells that cause a large number of serious human injuries. In this review, we evaluate the toxinology of these venomous animals. Results: Some of inoculated venom symptoms included the immediate and intense pain, inflammation and skin necrosis, bleeding wounds, acute edema, salivation, nausea, vomiting, diarrhea, fever, headaches, muscle cramps, tremors, paralysis, dyspnea, cardiovascular collapse, local vasoconstriction, seizures, coma, and rarely death. The venom contains 5-HT, 5-nucleotidase, acetylcholine , phosphodiesterase, proteolytic enzymes against casein, gelatin, and fibrinogen, and several toxins such as cystatins, galectin, peroxiredoxin 6, orpotrin and porflan, and other peptids and proteins including alpha subunit haemoglobin, ganglioside GM2 activator, glutathione s-transferase µ, leukocyte elastase inhibitor, transaldolase, ATP synthase, nucleoside diphosphate kinase and type III intermediate filament. Galectin has a diverse functions including anticoagulant, procoagulant, platelet-modulating, myotoxic and haemagglutination activities. Cystatins are potent inhibitors of cysteine proteinases, including papain and the cathepsins. Hydrolysis of lipids through PLA2 activity is one of the most important functions of peroxiredoxin-6. Orpotrin and porflan have vasoconstrictive and inflammatory effects, respectively. Conclusion: Stingray venoms have different toxins and bioactive molecules with diverse mechanisms of toxicities. A thorough understanding of the toxicities mechanisms and clinical manifestations of stingrays’ venoms will provide the ability to treat effectively and manage injuries with this animals by clinicians and toxinologists.

Functional consequences of structural differences in stingray sensory systems. Part I: mechanosensory lateral line canals.

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Jordan, Laura K; Kajiura, Stephen M; Gordon, Malcolm S

2009-10-01

Short range hydrodynamic and electrosensory signals are important during final stages of prey capture in elasmobranchs (sharks, skates and rays), and may be particularly useful for dorso-ventrally flattened batoids with mouths hidden from their eyes. In stingrays, both the lateral line canal and electrosensory systems are highly modified and complex with significant differences on ventral surfaces that relate to feeding ecology. This study tests functional hypotheses based on quantified differences in sensory system morphology of three stingray species, Urobatis halleri, Myliobatis californica and Pteroplatytrygon violacea. Part I investigates the mechanosensory lateral line canal system whereas part II focuses on the electrosensory system. Stingray lateral line canals include both pored and non-pored sections and differ in branching complexity and distribution. A greater proportion of pored canals and high pore numbers were predicted to correspond to increased response to water flow. Behavioral experiments were performed to compare responses of stingrays to weak water jets mimicking signals produced by potential prey at velocities of 10-20 cm s(-1). Bat rays, M. californica, have the most complex and broadly distributed pored canal network and demonstrated both the highest response rate and greater response intensity to water jet signals. Results suggest that U. halleri and P. violacea may rely on additional sensory input, including tactile and visual cues, respectively, to initiate stronger feeding responses. These results suggest that stingray lateral line canal morphology can indicate detection capabilities through responsiveness to weak water jets.

[Stingrays in rivers in southeastern Brazil: occurrence localities and impact on the population].

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Garrone Neto, Domingos; Haddad Junior, Vidal

2010-01-01

In this paper, our aim was to describe the process of colonization of the upper Paraná basin, southeastern Brazil, by stingrays, showing the current situation, likely trend and impact caused and discussing some management actions and mitigation measures. Interviews were held with riverbank people and health professionals, to gather information on occurrences of stingrays and accidents associated with these animals, along with underwater observations and collection of specimens, between 2004 and 2009 in localities in the States of São Paulo, Paraná and Mato Grosso do Sul, in the southeastern, southern and part of the central-western regions of Brazil. Three species of stingrays were identified in the study area, thus demonstrating that they were using the paths opened by the Tietê-Paraná Waterway to disperse. Sixteen victims of accidents involving these animals were found, mainly bathers and fishermen. Attention was drawn to the fact that these cases had not been reported, yet they presented high morbidity with notable temporary incapacity for work. This is the first report on biological invasion involving species of elasmobranchs in the literature and, because stingrays are colonizing densely populated areas and are expanding their range of distribution each year, it can be expected that their negative interactions with humans will intensify, with important changes in the epidemiological profile of accidents due to venomous animals occurring in southeastern Brazil.

Natural outbreak of Streptococcus agalactiae (GBS) infection in wild giant Queensland grouper, Epinephelus lanceolatus (Bloch), and other wild fish in northern Queensland, Australia.

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Bowater, R O; Forbes-Faulkner, J; Anderson, I G; Condon, K; Robinson, B; Kong, F; Gilbert, G L; Reynolds, A; Hyland, S; McPherson, G; Brien, J O'; Blyde, D

2012-03-01

Ninety-three giant Queensland grouper, Epinephelus lanceolatus (Bloch), were found dead in Queensland, Australia, from 2007 to 2011. Most dead fish occurred in northern Queensland, with a peak of mortalities in Cairns in June 2008. In 2009, sick wild fish including giant sea catfish, Arius thalassinus (Rüppell), and javelin grunter, Pomadasys kaakan (Cuvier), also occurred in Cairns. In 2009 and 2010, two disease epizootics involving wild stingrays occurred at Sea World marine aquarium. Necropsy, histopathology, bacteriology and PCR determined that the cause of deaths of 12 giant Queensland grouper, three wild fish, six estuary rays, Dasyatis fluviorum (Ogilby), one mangrove whipray, Himantura granulata (Macleay), and one eastern shovelnose ray, Aptychotrema rostrata (Shaw), was Streptococcus agalactiae septicaemia. Biochemical testing of 34 S. agalactiae isolates from giant Queensland grouper, wild fish and stingrays showed all had identical biochemical profiles. The 16S rRNA gene sequences of isolates confirmed all isolates were S. agalactiae; genotyping of selected S. agalactiae isolates showed the isolates from giant Queensland grouper were serotype Ib, whereas isolates from wild fish and stingrays closely resembled serotype II. This is the first report of S. agalactiae from wild giant Queensland grouper and other wild tropical fish and stingray species in Queensland, Australia. © 2012 Blackwell Publishing Ltd and State of Queensland.

Injuries by marine and freshwater stingrays: history, clinical aspects of the envenomations and current status of a neglected problem in Brazil.

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Junior, Vidal Haddad; Cardoso, João Luiz Costa; Neto, Domingos Garrone

2013-07-29

Stingrays are a group of rays - cartilaginous fish related to sharks - that have whiplike tails with barbed, usually venomous spines and are found around the world, especially the marine species. Despite recent reports of accidents involving these fish, they are not aggressive, reacting only when stepped on or improperly handled. Injuries by stingrays are seldom mentioned by historians, although they have always been present in riverine communities of inland waters and in South American coasts. Indeed, envenomations by stingrays are quite common in freshwater and marine fishing communities. Although having high morbidity, such injuries are neglected because they have low lethality and usually occur in remote areas, which favor the use of folk remedies. In the present review article, historical aspects of injuries caused by stingrays in Brazil and their distribution on the coast of São Paulo state and riverine communities of the North, Midwest and Southeast regions were studied. In addition, other aspects were analyzed such as clinical features, therapeutic methods, preventive measures and trends in occurrence of these accidents in the country, particularly in areas in which freshwater stingrays had not been previously registered, being introduced after breaching of natural barriers.

Stingray tidal stream energy device - phase 3

International Nuclear Information System (INIS)

2005-01-01

The 150 kW Stingray demonstrator was designed, built and installed by The Engineering Business (EB) in 2002, becoming the world's first full-scale tidal stream generator. The concept and technology are described in the reports from Phases 1 and 2 of the project. This report provides an overview of Phase 3 - the re-installation of Stingray in Yell Sound in the Shetland Isles between July and September 2003 for further testing at slack water and on the flood tide to confirm basic machine characteristics, develop the control strategy and to demonstrate performance and power collection through periods of continuous operation. The overall aim was to demonstrate that electricity could be generated at a potentially commercially viable unit energy cost; cost modelling indicated a future unit energy cost of 6.7 pence/kWh when 100 MW capacity had been installed. The report describes: project objectives, targets and activities; design and production; marine operations including installation and demobilisation; environmental monitoring and impact, including pre-installation and post-decommissioning surveys; stakeholder involvement; test results on machine characteristics, sensor performance, power cycle analysis, power collection, transmission performance and efficiency, current data analysis; validation of the mathematical model; the background to the economic model; cost modelling; and compliance with targets set by the Department of Trade and Industry (DTI)

Stingray tidal stream energy device - phase 3

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

The 150 kW Stingray demonstrator was designed, built and installed by The Engineering Business (EB) in 2002, becoming the world's first full-scale tidal stream generator. The concept and technology are described in the reports from Phases 1 and 2 of the project. This report provides an overview of Phase 3 - the re-installation of Stingray in Yell Sound in the Shetland Isles between July and September 2003 for further testing at slack water and on the flood tide to confirm basic machine characteristics, develop the control strategy and to demonstrate performance and power collection through periods of continuous operation. The overall aim was to demonstrate that electricity could be generated at a potentially commercially viable unit energy cost; cost modelling indicated a future unit energy cost of 6.7 pence/kWh when 100 MW capacity had been installed. The report describes: project objectives, targets and activities; design and production; marine operations including installation and demobilisation; environmental monitoring and impact, including pre-installation and post-decommissioning surveys; stakeholder involvement; test results on machine characteristics, sensor performance, power cycle analysis, power collection, transmission performance and efficiency, current data analysis; validation of the mathematical model; the background to the economic model; cost modelling; and compliance with targets set by the Department of Trade and Industry (DTI).

Three new stingrays (Myliobatiformes: Dasyatidae) from the Indo-West Pacific.

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Last, Peter R; White, William T; Naylor, Gavin

2016-08-05

Three undescribed stingrays were discovered as part of a broader revision of the family Dasyatidae that formed part of the Chondrichthyan Tree of Life project. This research forms part of a sequence of papers on rays aimed at describing unnamed species for inclusion in a multi-authored guide to rays of the world. The first part of this series focused on a redefinition of genera of the family Dasyatidae. The new Indo-West Pacific taxa are represented by separate genera from three dasyatid subfamilies: Himantura australis sp. nov. (northern Australia and Papua New Guinea), Taeniura lessoni sp. nov. (Melanesia) and Telatrygon biasa sp. nov. (Indo-Malay Archipelago). Himantura australis sp. nov., which belongs to a complex of four closely related reticulate whiprays, differs subtly from its congeners in coloration, morphometrics and distribution. Taeniura lessoni sp. nov. is the second species in a genus containing the widely-distributed T. lymma, which is possibly the most abundant stingray in shallow coral-reef habitats of the Indo-Pacific, with the new species apparently restricted to Melanesia. Taeniura lessoni sp. nov. is distinguishable by the absence of a distinctive pair of vivid blue longitudinal stripes on the dorsolateral edges of the tail which is one of the most distinctive features of T. lymma. Telatrygon biasa sp. nov. belongs to a small, recently designated genus of stingrays represented by four species in the tropical Indo-West Pacific. Telatrygon biasa sp. nov. differs from these species in morphometrics. The new species differs markedly from T. zugei in its NADH2 sequence. Telatrygon crozieri is resurrected as a valid northern Indian Ocean representative of the T. zugei complex.

Local-regional anesthesia in the management of stingray stings: Experience of the Bouffard medical-surgical hospital in Djibouti.

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Vanoye, C; Lacroix, G; Le Gonidec, E; Couret, A; Benois, A; Peigne, V

2017-02-01

Stingray injuries are very painful. Systemic analgesics are ineffective, and the use of local-regional anesthesia has been reported. This retrospective descriptive study reviewed all cases of stingray injuries seen at the emergency department of the Bouffard Hospital (Djbouti, Africa) between 2011 and 2014. The study included 35 patients. Most of the injuries (n= 31, 89%) concerned the lower limbs. Median pain intensity was 6 [5-8] on a visual analog scale of 0 (no pain) to 10. The following systemic medications were administered: acetaminophen to 13 (27%) patients, morphine to 8 (23%), and tramadol to 6 (17%). In all, 25 (71%) patients received local-regional anesthesia, 15 (60%) by injections at the ankle. All procedures were successful, and no adverse event was reported. This study reports clinical data about stingray injuries in the Red Sea area and highlights the interest of local-regional anesthesia in their management. Most of the procedures were distal and could be performed by trained emergency physicians.

The Nature of the Stingray Nebula from Radio Observations

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Harvey-Smith, Lisa; Hardwick, Jennifer A.; De Marco, Orsola; Parthasarathy, Mudumba; Gonidakis, Ioannis; Akhter, Shaila; Cunningham, Maria; Green, James A.

2018-06-01

We have analysed the full suite of Australia Telescope Compact Array data for the Stingray planetary nebula. Data were taken in the 4- to 23-GHz range of radio frequencies between 1991 and 2016. The radio flux density of the nebula generally declined during that period, but between 2013 and 2016 it shows signs of halting that decline. We produced the first spatially resolved radio images of the Stingray nebula from data taken in 2005. A ring structure, which appears to be associated with the ring seen in HST images, was visible. In addition, we found a narrow extension to the radio emission towards the eastern and western edges of the nebula. We derived the emission measure of the nebula - this decreased between 1992 and 2011, suggesting that the nebula is undergoing recombination. The radio spectral index is broadly consistent with a free-free emission mechanism, however a single data point hints that a steeper spectral index has possibly emerged since 2013, which could indicate the presence of synchrotron emission. If a non-thermal component component has emerged, such as one associated with a region that is launching a jet or outflow, we predict that it would intensify in the years to come.

NHE3 in an ancestral vertebrate: primary sequence, distribution, localization, and function in gills.

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Choe, Keith P; Kato, Akira; Hirose, Shigehisa; Plata, Consuelo; Sindic, Aleksandra; Romero, Michael F; Claiborne, J B; Evans, David H

2005-11-01

In mammals, the Na+/H+ exchanger 3 (NHE3) is expressed with Na+/K+-ATPase in renal proximal tubules, where it secretes H+ and absorbs Na+ to maintain blood pH and volume. In elasmobranchs (sharks, skates, and stingrays), the gills are the dominant site of pH and osmoregulation. This study was conducted to determine whether epithelial NHE homologs exist in elasmobranchs and, if so, to localize their expression in gills and determine whether their expression is altered by environmental salinity or hypercapnia. Degenerate primers and RT-PCR were used to deduce partial sequences of mammalian NHE2 and NHE3 homologs from the gills of the euryhaline Atlantic stingray (Dasyatis sabina). Real-time PCR was then used to demonstrate that mRNA expression of the NHE3 homolog increased when stingrays were transferred to low salinities but not during hypercapnia. Expression of the NHE2 homolog did not change with either treatment. Rapid amplification of cDNA was then used to deduce the complete sequence of a putative NHE3. The 2,744-base pair cDNA includes a coding region for a 2,511-amino acid protein that is 70% identical to human NHE3 (SLC9A3). Antisera generated against the carboxyl tail of the putative stingray NHE3 labeled the apical membranes of Na+/K+-ATPase-rich epithelial cells, and acclimation to freshwater caused a redistribution of labeling in the gills. This study provides the first NHE3 cloned from an elasmobranch and is the first to demonstrate an increase in gill NHE3 expression during acclimation to low salinities, suggesting that NHE3 can absorb Na+ from ion-poor environments.

Ergasilus trygonophilus sp. nov. (Copepoda: Ergasilidae a branchial parasite of freshwater stingrays (Potamotrygonidae from state of Pará, Brazil

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Marcus V. Domingues

2010-10-01

Full Text Available Ergasilus trygonophilus sp. nov. is described from freshwater stingrays (Potamotrygon spp. and Plesiotrygon iwamae Rosa, Castello & Thorson, 1987 from the state of Pará, Brazil. The new species differs from all known species of Ergasilus Nordman, 1832 from Brazilian waters by possessing: (1 an elongate bullet-shaped cephalosome; (2 antennule setal formula 1: 10: 4: 4: 2 + 1 ae: 6 + 1 ae; (3 maxillule bearing two distal setae; and (4 terminal endopodal segment of leg 1 with rosette-like array of blunt spinules. This is the first species of a freshwater stingray Ergasilus reported from Brazil.

Development and Evaluation of the Stingray, an Amphibious Maritime Interdiction Operations Unmanned Ground Vehicle

Science.gov (United States)

2014-05-01

include: • Size and weight: The robot should fit in a Modular Lightweight Load-carrying Equipment ( MOLLE ) pouch and weigh approximately 1.5 Kg. • Ground...volumetric envelope for the Stingray was determined by the requirement to fit in a MOLLE pouch. It had repercussions in terms of the wheelbase, width

Antimicrobial and Anti-Proliferative Effects of Skin Mucus Derived from Dasyatis pastinaca (Linnaeus, 1758

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Virginia Fuochi

2017-11-01

Full Text Available Resistance to chemotherapy occurs in various diseases (i.e., cancer and infection, and for this reason, both are very difficult to treat. Therefore, novel antimicrobial and chemotherapic drugs are needed for effective antibiotic therapy. The aim of the present study was to assess the antimicrobial and anti-proliferative effects of skin mucus derived from Dasyatis pastinaca (Linnaeus, 1758. Our results showed that skin mucus exhibited a significant and specific antibacterial activity against Gram-negative bacteria but not against Gram-positive bacteria. Furthermore, we also observed a significant antifungal activity against some strains of Candida spp. Concerning anti-proliferative activity, we showed that fish mucus was specifically toxic for acute leukemia cells (HL60 with an inhibition of proliferation in a dose dependent manner (about 52% at 1000 μg/mL of fish skin mucous, FSM. Moreover, we did not observe effects in healthy cells, in neuroblastoma cells (SH-SY5Y, and multiple myeloma cell lines (MM1, U266. Finally, it exhibited strong expression and activity of chitinase which may be responsible, at least in part, for the aforementioned results.

Stiffening the stingray skeleton - an investigation of durophagy in myliobatid stingrays (Chondrichthyes, batoidea, myliobatidae).

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Summers, A P

2000-02-01

The stingray family Myliobatidae contains five durophagous (hard prey specialist) genera and two planktivorous genera. A suite of morphological features makes it possible for the hard prey specialists to crush mollusks and crustaceans in their cartilaginous jaws. These include: 1) flat, pavement-like tooth plates set in an elastic dental ligament; 2) multiple layers of calcified cartilage on the surface of the jaws; 3) calcified struts running through the jaws; and 4) a lever system that amplifies the force of the jaw adductors. Examination of a range of taxa reveals that the presence of multiple layers of calcified cartilage, previously described from just a few species, is a plesiomorphy of Chondrichthyes. Calcified struts within the jaw, called "trabecular cartilage," are found only in the myliobatid genera, including the planktivorous Manta birostris. In the durophagous taxa, the struts are concentrated under the area where prey is crushed, thereby preventing local buckling of the jaws. Trabecular cartilage develops early in ontogeny, and does not appear to develop as a direct result of the stresses associated with feeding on hard prey. A "nutcracker" model of jaw function is proposed. In this model, the restricted gape, fused mandibular and palatoquadrate symphyses, and asynchronous contraction of the jaw adductors function to amplify the closing force by 2-4 times. Copyright 2000 Wiley-Liss, Inc.

Enhancing the economic value and consumer preferences of commercial mondol stingray (Himantura gerardi) leather creative products

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Sahubawa, L.; Pertiwiningrum, A.; Rahmadian, Y.

2018-03-01

The research objectives were to design, assess the economic value and consumer preference level of stingray leather products. The research method included a product design, analysis of economic value and consumer preferences. Mondol stingray (Himantura gerardi) leather, with a length of 50 cm and width of 30 cm, were processed into ID card wallet, man and women’s wallet and key holder. The number of respondents involved to analyze the preference level is 75 respondents (students, lecturers and employees of Universitas Gadjah Mada). Indicators of consumer preferences were model, color, price and purchasing power. The price of ID card wallet is Rp. 450,000; women wallet is Rp. 650,000 and a key holder is Rp. 300,000. Consumer preferences on ID card wallet were as follow: 84 % stated very interesting model; 83 % stated very interesting color; 61 % stated cheap and 53 % had enough. Consumer preferences of women’s wallet were as follow: 81 % stated very interesting model; 84 % stated very interesting color; 56 % stated cheap and 57 % had enough. Consumer preferences on key holder were as follow: 49 % stated interesting model; 72 % stated very interesting color; 61 % stated cheap and 57 % had enough.

Seeing the forest before the trees-spatial orientation in freshwater stingrays (Potamotrygon motoro) in a hole-board task.

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Schluessel, V; Herzog, H; Scherpenstein, M

2015-10-01

Freshwater stingrays (Potamotrygon motoro) have been shown to use a variety of spatial learning strategies including directional, landmark and place learning. In the present study, the significance of landmarks and geometric cues was investigated in a hole-board task. The aim was to determine cue preferences and collect additional information on the orientation mechanisms used in elasmobranchs. In four experiments, five juvenile stingrays had to memorize a fixed goal location within either a rectangular or a circular arena in the presence of goal-associated, signaling landmarks, proximal and distal cues. Transfer tests elucidated which cues the rays used or favored to reach the goal position. All rays successfully solved three of four tasks; as expected, different strategies were used in the process. Small alterations in the positioning of signaling landmarks (causing a spatial conflict between the previous feeding location and the new position of the signaling landmark) caused individuals to visit both locations equally often, whereas large alterations caused animals to ignore signaling cues and return to the previous feeding location. In the last and most complex experiment, three of five rays found the feeding location by remembering the positions of both proximate and distal landmarks in addition to memorizing particular swimming paths. Results showed that rays generally placed more importance on the overall environmental or geometric arrangement of the arena than on (individual) landmarks. This seems ecologically feasible, as distinct landmarks (e.g. rocks, pieces of wood, water plants) in the rays' natural environment may be more easily altered, removed or obscured from view than global ones (e.g. a river bend), which tend to be more stable. Overall, these results confirm those of previous studies, in that freshwater stingrays orient visually, learn quickly and can apply various orientation strategies, which are not mutually exclusive. Copyright © 2015

A comparative analysis of feeding and trophic level ecology in stingrays (Rajiformes; Myliobatoidei and electric rays (Rajiformes: Torpedinoidei.

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Ian P Jacobsen

Full Text Available Standardised diets and trophic level (T L estimates were calculated for 75 ray species from the suborders Myliobatoidei (67 spp. and Torpedinoidei (8 spp.. Decapod crustaceans (31.71 ± 3.92% and teleost fishes (16.45 ± 3.43% made the largest contribution to the standardised diet of the Myliobatoidei. Teleost fishes (37.40 ± 16.09% and polychaete worms (31.96 ± 14.22% were the most prominent prey categories in the standardised diet of the suborder Torpedinoidei. Cluster analysis identified nine major trophic guilds the largest of which were decapod crustaceans (24 species, teleost fishes (11 species and molluscs (11 species. Trophic level estimates for rays ranged from 3.10 for Potamotrygon falkneri to 4.24 for Gymnura australis, Torpedo marmorata and T. nobiliana. Secondary consumers with a T L <4.00 represented 84% of the species examined, with the remaining 12 species (16% classified as tertiary consumers (T L ≥ 4.00. Tertiary consumers included electric rays (Torpedo, 3 spp. and Hypnos, 1 sp., butterfly rays (Gymnura, 4 spp., stingrays (2 spp. and Potamotrygonid stingrays (2 spp.. Feeding strategies were identified as the primary factor of influence with respect to Myliobatoidei and Torpedinoidei T L estimates with inter-family comparisons providing the greatest insight into Myliobatoidei and Torpedinoidei relationships.

PERUBAHAN KARAKTERISTIK SURIMI IKAN CUCUT DAN IKAN PARI AKIBAT PENGARUH PENGKOMPOSISIAN DAN PENYIMPANAN DINGIN DAGING LUMAT [Characteristic Changes of Shark and Stingray Surimi as Affected by Compositioning and Chill Storage of the Mince Fish

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Joko Santoso1

2008-06-01

Full Text Available This experiment was carried out to study the effects of leaching, compositioning, and chill storage of mince fish on the characteristic changes of surimi from shark and stingray fish. Three times leaching of mince fish could reduce the urea contents of the shark and stingray as much as 88% and 100%, respectively; with the salt soluble protein contents were 13.52% and 13.24%, respectively. Mixture of mince shark and stingray in proportion of 25% : 75% (A1B2 gave the highest value of gel strength being 209.29 g.cm in comparison with others composition. During chill storage, deterioration process still occurred as indicated by increasing value of acidity and contents of base volatile compounds i.e. total volatile base nitrogen (TVBN and tri-methyl amine (TMA; and also decreasing contents of urea and salt soluble protein. Deterioration process of mince fish also affected the physical characteristic of surimi i.e. decreasing values of gel strength, water holding capacity (WHC, and colour (whiteness.

[Peculiarities of the phospholipid and fatty acid composition of erythrocyte plasma membranes of the Black Sea fish].

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Silkin, Iu A; Silkina, E N; Zabelinskiĭ, S A

2012-01-01

The phospholipid and the fatty acid composition of the main phospholipids families of erythrocyte plasma membranes was studied in two species of cartilaginous fish: the common thrasher (Raja clavata L.) and the common stingray (Dasyatis pastinaca) and three bony fish species: the scorpion fish (Scorpaena porcus L.), the smarida (Spicara flexuosa Raf.), and the horse mackerel (Trachurus mediterraneus ponticus Aleev). It was shown that in the studied fish, 70.0-80.0 % of all membrane phospholipids were composed of phosphatidylcholine and phosphatidylethanolamine. Phosphatidylserine, monophosphoinositide, and sphingomyelin were minor components whose content in the erythrocyte membrane fluctuated from 3.0 % to 13.0 %. The fatty acid phospholipids composition was represented by a large specter of acids. From saturated acids, basic for plasma membranes are palmitic (C16: 0) and stearic (C18: 0) acids. From unsaturated acids, the larger part belong to mono-, tetra-, penta-, and hexaenoic acids in fish phospholipids. The calculation of the double bond index and of the unsaturation coefficient showed difference in the deformation ability of erythrocyte membranes of the studied fish.

Gill dimensions in near-term embryos of Amazonian freshwater stingrays (Elasmobranchii: Potamotrygonidae and their relationship to the lifestyle and habitat of neonatal pups

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Wallice Paxiúba Duncan

Full Text Available This comparative study of gill morphometrics in near-term embryos of freshwater stingray potamotrygonids examines gill dimensions in relation to neonatal lifestyle and habitat. In embryos of the potamotrygonids Paratrygon aiereba, Plesiotrygon iwamae, Potamotrygon motoro, Potamotrygon orbignyi, and cururu ray Potamotrygon sp. the number and length of filaments, total gill surface area, mass-specific surface area, water-blood diffusion distance, and anatomical diffusion factor were analysed. In all potamotrygonids, the 3rd branchial arch possessed a larger respiratory surface than the other gill arches. Larger embryos had more gill surface area and large spiracles, which are necessary to maintain the high oxygen uptake needed due to their larger body size. However, the higher mass-specific gill surface area observed in near-term embryos may be advantageous because neonates can use hypoxic environments as refuges against predators, as well as catch small prey that inhabit the same environment. As expected from their benthic mode of life, freshwater stingrays are sluggish animals compared to pelagic fishes. However, based on gill respiratory morphometry (such as gill area, mass-specific gill area, the water-blood diffusion barrier, anatomical diffusion factor, and relative opening of the spiracle, subtypes of lifestyles can be observed corresponding to: active, intermediate, and sluggish species according to Gray's scale.

A retrospective study of disease in elasmobranchs.

Science.gov (United States)

Garner, M M

2013-05-01

This report reviews diseases of 1546 elasmobranchs representing at least 60 species submitted to Northwest ZooPath from 1994 to 2010. Cownose rays (Rhinoptera bonasus) (78), southern rays (Dasyatis americana) (75), dusky smooth-hounds (Mustelus canis) (74), bonnethead sharks (Sphyrna tiburo) (66), and bamboo sharks (Hemiscylliidae) (56) were the most commonly submitted species. Infectious/inflammatory disease was most common (33.5%) followed by nutritional (11.9%, mostly emaciation), traumatic (11.3%), cardiovascular (5.5%, mostly shock), and toxin-associated disease (3.7%). Bacterial infections (518/1546, 15%) included sepsis (136/518, 26%), dermatitis (7%), branchitis (6%), and enteritis (4%). Fungal infections (10/1546, 0.6%) included dermatitis (30%), hepatitis (30%), and branchitis (20%). Viral or suspected viral infections or disease processes (15/1546, 1%) included papillomatosis (47%), herpesvirus (20%), and adenovirus (7%). Parasitic infections (137/1546, 9%) included nematodiasis (36/137, 26%), ciliate infections (23%), trematodiasis (20%), coccidiosis (6%), myxozoanosis (5%), amoebiasis (4%), cestodiasis (1%), and flagellate infections (1%). Inflammation of unknown cause (401/1546, 26%) included enteritis (55/401, 14%), branchitis (9%), encephalitis (9%), and dermatitis (7%). Traumatic diseases (174/1546, 11.3%) included skin trauma (103/174, 60%), stress/maladaptation (9%), and gut trauma (7%). Toxicoses (57/1546, 4%) included toxic gill disease (16/57, 26%), gas bubble disease (19%), fenbendazole (7%), ammonia (7%), chlorine (5%), and chloramine (3%). Species trends included visceral nematodiasis in black-nosed sharks (Carcharhinus acronotus) (55%); sepsis in dusky smooth-hounds (41%), blue-spotted stingrays (36%), southern rays (36%), and wobeggong sharks (Orectolobus spp) (69%); emaciation in bamboo (33%) and bonnethead (32%) sharks and freshwater stingrays (Potamotrygon motoro) (32%); and trauma in bonnethead sharks (30%).

Exploited but Unevaluated: DNA Barcoding Reveals Skates and Stingrays (Chordata, Chondrichthyes Species Landed in the Indonesian Fish Market

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Hawis Madduppa

2016-06-01

Full Text Available Reliable and precise species identification is important to fisheries management and conservation. However, many rays and skates in Indonesia are currently being exploited and landed into traditional fish market without a proper identification. Therefore, this study was conducted to identify species of skates and stingrays that were landed and traded in three fish markets in Indonesia (Palabuhanratu, Muara Saban, and Lampung using molecular techniques and to determine the conservation status of the identified species based on IUCN (International Union for Conservation of Nature and Natural Resources as well as defined by CITES (Convention on International Trade in Endangered Species. The mitochondrial cytochrome oxidase I (COI gene was amplified by polymerase chain reaction (PCR using a pair of primer, fish-BCL and fish-BCH. Of 29 tissue samples collected from the study sites, a total of five species were successfully identified: Dipturus chilensis (4, Himantura walga (1, Neotrygon kuhlii (11, Taeniura lymma (9 and Rhinoptera javanica (4. The Neighbor Joining phylogeny of mitochondrial lineages, based on partial COI gene sequences, the ingroup haplotypes were clustered into five main clades representing each species. The identified stingrays were being listed as vulnerable (D. chilensis and R. javanica, near threatened (H. walga and T. lymma, and data deficient (N. kuhlii by IUCN, with two species (D. chilensis and H. walga population were indicated decreased. Unfortunately, all of identified species have not been evaluated by CITES regarding their trade status. As a consequences, a valuable effort should be placed to create a scientific network for monitoring programmes not only on a local scale, and to make pressure on governments for adopting molecular techniques as tools for controlling and avoiding misidentification. Keywords: Mitochondrial DNA, Phylogeny, Coral Triangle, Taxonomy, Fisheries

REPRODUCTIVE BIOLOGY OF THE VENEZUELA ROUND STINGRAY UROTRYGON VENEZUELAE SCHULTZ FROM THE COLOMBIAN CARIBBEAN

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KELLY ACEVEDO

2015-06-01

Full Text Available As for most batoid species, little is known about the basic biology of the Venezuela round stingray Urotrygon venezuelae (Urotrygonidae. This study presents information about the reproductive biology of the species, including fecundity, embryonic development stage, relationship between maternal size and fecundity, gonadosomatic (GSI and hepatosomatic (HSI indices, sex ratios, maturity size and size at birth. With all this information, a preliminary reproductive cycle is proposed. A total of 269 specimens were caught with beach seine in Salguero beach, Colombian Caribbean Sea, between August 2005 and October 2006. We propose for U. venezuelae a biological cycle with three reproductive peaks: November-December, March-April and August. Size at sexual maturity was calculated in 176 mm (total length for females and 227 mm for males; fecundity ranged between one and six embryos per female. We found that cloacal diameter and liver weight were better predictors for fecundity than total length for U. venezuelae.

Swimming near the substrate: a simple robotic model of stingray locomotion

International Nuclear Information System (INIS)

Blevins, Erin; Lauder, George V

2013-01-01

Studies of aquatic locomotion typically assume that organisms move through unbounded fluid. However, benthic fishes swim close to the substrate and will experience significant ground effects, which will be greatest for fishes with wide spans such as benthic batoids and flatfishes. Ground effects on fixed-wing flight are well understood, but these models are insufficient to describe the dynamic interactions between substrates and undulating, oscillating fish. Live fish alter their swimming behavior in ground effect, complicating comparisons of near-ground and freestream swimming performance. In this study, a simple, stingray-inspired physical model offers insights into ground effects on undulatory swimmers, contrasting the self-propelled swimming speed, power requirements, and hydrodynamics of fins swimming with fixed kinematics near and far from a solid boundary. Contrary to findings for gliding birds and other fixed-wing fliers, ground effect does not necessarily enhance the performance of undulating fins. Under most kinematic conditions, fins do not swim faster in ground effect, power requirements increase, and the cost of transport can increase by up to 10%. The influence of ground effect varies with kinematics, suggesting that benthic fish might modulate their swimming behavior to minimize locomotor penalties and incur benefits from swimming near a substrate. (paper)

Paratrygon aiereba (Müller & Henle, 1841: the senior synonym of the freshwater stingray disceus thayeri Garman, 1913 (chondrichthyes: potamotrygonidae

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Ricardo S. Rosa

1990-01-01

Full Text Available A review of the original descriptions and available types of the South American freshwater stingrays Trygon aiereba Müller & Henle, 1841, Trygon strogylopterus Schomburgk, 1843 and Disceus thayeri Garman, 1913 indicates that these three nominal species are synonymous. The senior name, placed in the monotypic genus Paratrygon Duméril, 1865, established for Trygon aiereba, is available and valid. Based on its description, T. aiereba is a freshwater stingray. Therefore, this taxon is not the same as Raja ajereba Walbaum and Raja orbicularis Schneider, both names established for the marine "Aiereba" of Marcgrave, and which preferably should be treated as nomina dubia. Paratrygon does not replace Potamotrygon Garman, 1877 as the type genus, because the family name Potamotrygonidae Garman, 1877 has priority over Paratrygonidade Gill, 1893.A revisão das descrições originais e dos tipos existentes das raias de água doce Trygon aiereba Müller & Henle, 1841, Trygon strogylopterus Schomburgk, 1843, e Disceus thayeri Garman, 1913, indica que essas três espécies nominais são sinônimas. O nome sênior, colocado no gênero monotípico Paratrygon Duméril, 1865, estabelecido para T. aiereba, é disponível e válido. A descrição de T. aiereba corresponde claramente a uma raia de agua doce; portanto esta espécie não é um sinônimo de Raja ajereba Walbaum e de Raja orbicularis Schneider, ambos os nomes propostos para a "Aiereba " marinha de Marcgrave, e que preferivelmente devem ser tratados como nomina dubia. Paratrygon não substitui Potamotrygon Garman, 1877 como gênero-tipo, porque o nome de família Potamotrygonidae Garman, 1877 tem prioridade sobre Paratrygonidae Gill. 1893.

Development and evaluation of the Stingray, an amphibious maritime interdiction operations unmanned ground vehicle

Science.gov (United States)

Nguyen, Hoa G.; Castelli, Robin

2014-06-01

The U.S. Navy and Marine Corps conduct thousands of Maritime Interdiction Operations (MIOs) every year around the globe. Navy Visit, Board, Search, and Seizure (VBSS) teams regularly board suspect ships and perform search operations, often in hostile environments. There is a need for a small tactical robot that can be deployed ahead of the team to provide enhanced situational awareness in these boarding, breaching, and clearing operations. In 2011, the Space and Naval Warfare Systems Center Pacific conducted user evaluations on a number of small throwable robots and sensors, verified the requirements, and developed the key performance parameters (KPPs) for an MIO robot. Macro USA Corporation was then tasked to design and develop two prototype systems, each consisting of one control/display unit and two small amphibious Stingray robots. Technical challenges included the combination paddle wheel/shock-absorbing wheel, the tradeoff between impact resistance, size, and buoyancy, and achieving adequate traction on wet surfaces. This paper describes the technical design of these robots and the results of subsequent user evaluations by VBSS teams.

[An intriguing model for 5S rDNA sequences dispersion in the genome of freshwater stingray Potamotrygon motoro (Chondrichthyes: Potamotrygonidae)].

Science.gov (United States)

Cruz, V P; Oliveira, C; Foresti, F

2015-01-01

5S rDNA genes of the stingray Potamotrygon motoro were PCR replicated, purified, cloned and sequenced. Two distinct classes of segments of different sizes were obtained. The smallest, with 342 bp units, was classified as class I, and the largest, with 1900 bp units, was designated as class II. Alignment with the consensus sequences for both classes showed changes in a few bases in the 5S rDNA genes. TATA-like sequences were detected in the nontranscribed spacer (NTS) regions of class I and a microsatellite (GCT) 10 sequence was detected in the NTS region of class II. The results obtained can help to understand the molecular organization of ribosomal genes and the mechanism of gene dispersion.

HASIL TANGKAP SAMPINGAN (HTS KAPAL RAWAI TUNA DI SAMUDERA HINDIA YANG BERBASIS DI BENOA

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Bram Setyadji

2016-05-01

Dasyatidae (Dasyatis spp. were those which dominated the composition, followed by group of billfishes, sharks and stingrays, teleostei fishes, and sea turtle. By-catch in this research mostly categorised as by-product due to its high economic value except for lancetfish and rays (Dasyatidae which still categorised as discards.

Always chew your food: freshwater stingrays use mastication to process tough insect prey.

Science.gov (United States)

Kolmann, Matthew A; Welch, Kenneth C; Summers, Adam P; Lovejoy, Nathan R

2016-09-14

Chewing, characterized by shearing jaw motions and high-crowned molar teeth, is considered an evolutionary innovation that spurred dietary diversification and evolutionary radiation of mammals. Complex prey-processing behaviours have been thought to be lacking in fishes and other vertebrates, despite the fact that many of these animals feed on tough prey, like insects or even grasses. We investigated prey capture and processing in the insect-feeding freshwater stingray Potamotrygon motoro using high-speed videography. We find that Potamotrygon motoro uses asymmetrical motion of the jaws, effectively chewing, to dismantle insect prey. However, CT scanning suggests that this species has simple teeth. These findings suggest that in contrast to mammalian chewing, asymmetrical jaw action is sufficient for mastication in other vertebrates. We also determined that prey capture in these rays occurs through rapid uplift of the pectoral fins, sucking prey beneath the ray's body, thereby dissociating the jaws from a prey capture role. We suggest that the decoupling of prey capture and processing facilitated the evolution of a highly kinetic feeding apparatus in batoid fishes, giving these animals an ability to consume a wide variety of prey, including molluscs, fishes, aquatic insect larvae and crustaceans. We propose Potamotrygon as a model system for understanding evolutionary convergence of prey processing and chewing in vertebrates. © 2016 The Author(s).

Seussapex, a new genus of lecanicephalidean tapeworm (Platyhelminthes: Cestoda) from the stingray genus Himantura (Myliobatiformes: Dasyatidae) in the Indo-West Pacific with investigation of mode of attachment.

Science.gov (United States)

Jensen, Kirsten; Russell, Shelbi L

2014-06-01

A new lecanicephalidean genus, Seussapex gen. n., is erected for specimens collected from stingrays from the Indo-West Pacific resembling the little known species Tenia [sic] narinari MacCallum, 1917 from the spotted eagle ray, Aetobatus narinari (Euphrasen). Members of this new genus are unique in their possession of a multi-tiered apical structure comprising a bipartite apical modification of the scolex proper, and an externally bipartite apical organ with anterior and posterior glandular compartments internally. The appearance of the scolex varies dramatically depending on state of protrusion and/or evagination of these different parts which appear to be able to function independently. Seussapex karybares sp. n. parasitizing Himantura uarnak 2 (sensu Naylor et al., 2012) in northern Australia is described as the type species and Tenia [sic] narinari is transferred to the new genus. The two species differ in scolex length and width of the posterior dome-shaped portion of the apical organ. Histological sections of scoleces stained using the periodic acid-Schiff(PAS) reaction showed the surface of the anterior part of the apical organ and the anterior glandular compartment to stain PAS positive, suggesting a chemical mode of attachment to the host's intestinal mucosal surface. Extensive collecting efforts of stingrays in the Indo-West Pacific shows Seussapex gen. n. to be restricted to species of Himantura Miller et Henle and suggests additional diversity in this group of hosts. In addition, the host identity of Seussapex narinari (MacCallum, 1917) comb. n. is called into question.

Influence of ontogeny and environmental exposure on mercury accumulation in muscle and liver of male Round Stingrays.

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Lyons, Kady; Carlisle, Aaron B; Lowe, Christopher G

2017-09-01

Mercury tissue distribution and its dynamics are poorly understood in elasmobranchs. Total mercury was measured in liver and muscle of male Round Stingrays (Urobatis halleri) from Seal Beach, California, an anthropogenically impacted site, and from the offshore island of Santa Catalina, a less impacted site. Stable isotope analysis was also performed on the muscle and red blood cells (RBCs) of a subset of rays over a range of age classes to investigate mercury accumulation with respect to trophic ecology. Mercury in both tissues was found to be significantly greater in adults than juveniles in mainland rays; however, liver mercury accumulation drastically increased after maturity and was significantly greater in mainland adult rays than Catalina rays. There were no patterns in δ 15 N or δ 13 C with size in muscle; however, there were indications of seasonal changes in RBC δ 15 N, suggesting short term shifts in diet or behavior is likely linked to reproductive status as is mercury accumulation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Trauma and envenoming caused by stingrays and other fish in a fishing community in Pontal do Paranapanema, state of São Paulo, Brazil: epidemiology, clinical aspects, and therapeutic and preventive measures.

Science.gov (United States)

Haddad, Vidal; Fávero, Edson Luiz; Ribeiro, Felipe Augusto Horácio; Ancheschi, Bruno da Costa; Castro, Gabriel Isaac Pereira de; Martins, Rafael Costa; Pazuelo, Guilherme Borghini; Fujii, Jun Ricardo; Vieira, Rodolfo Brum; Garrone Neto, Domingos

2012-01-01

Accidents caused by fish are common in inland fishing communities in Brazil, being work-related injuries in the majority of cases. These populations have no information on the mechanisms of trauma or envenoming. Through a questionnaire administered to fishermen, we obtained clinical and epidemiological data on accidents in Rosana, Pontal do Paranapanema, State of São Paulo, Brazil. These data were analyzed and converted into an easily understood prevention and treatment program for the colony. Thirty-nine fishermen replied to the survey. All of the patients had been hurt by fish. Of those mentioned, the yellow catfish (Pimelodus maculatus) was the main fish species associated with injuries, but others also caused trauma to the fishermen. Six fishermen had been envenomed by stingrays. Pain and ulcers were the main symptoms and were described as intolerable. Approximately half of those injured were treated using traditional folk remedies. The fishermen suffered multiple accidents with catfish, which are venomous and cause intense pain, as well as trauma due to other fish, such as surubins, traíras, freshwater croakers, and piranhas. Approximately 16% of those interviewed presented with envenomation from stingrays. Our data and previous experience in the area led to the creation of a pamphlet with clear language that can effectively help fishermen in the region, an area in need of health services and disease prevention. This initiative also applies to the whole La Plata River basin, which has similar fauna.

Trauma and envenoming caused by stingrays and other fish in a fishing community in Pontal do Paranapanema, state of São Paulo, Brazil: epidemiology, clinical aspects, and therapeutic and preventive measures

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Vidal Haddad Junior

2012-04-01

Full Text Available INTRODUCTION: Accidents caused by fish are common in inland fishing communities in Brazil, being work-related injuries in the majority of cases. These populations have no information on the mechanisms of trauma or envenoming. METHODS: Through a questionnaire administered to fishermen, we obtained clinical and epidemiological data on accidents in Rosana, Pontal do Paranapanema, State of São Paulo, Brazil. These data were analyzed and converted into an easily understood prevention and treatment program for the colony. RESULTS: Thirty-nine fishermen replied to the survey. All of the patients had been hurt by fish. Of those mentioned, the yellow catfish (Pimelodus maculatus was the main fish species associated with injuries, but others also caused trauma to the fishermen. Six fishermen had been envenomed by stingrays. Pain and ulcers were the main symptoms and were described as intolerable. Approximately half of those injured were treated using traditional folk remedies. CONCLUSIONS: The fishermen suffered multiple accidents with catfish, which are venomous and cause intense pain, as well as trauma due to other fish, such as surubins, traíras, freshwater croakers, and piranhas. Approximately 16% of those interviewed presented with envenomation from stingrays. Our data and previous experience in the area led to the creation of a pamphlet with clear language that can effectively help fishermen in the region, an area in need of health services and disease prevention. This initiative also applies to the whole La Plata River basin, which has similar fauna.

Evaluation of empowerment program to increase production capacity of fishery processing business in Semarang City, Indonesia

Science.gov (United States)

Swastawati, F.; Roessali, W.; Wijayanti, I.; Anggo, A. D.

2018-01-01

This study aims to evaluate the empowerment program to increase the production capacity of fishery product processing. Empowerment program was the implementation and utilization of science and technology in the area (IPTEKDA) LIPI Indonesia for Higher Education. Activity carried out in 2016 on fish processing industry “Lumintu Group”. Implementation of activities includes the transfer of technology to increase production capacity, business capital assistance in the form of production equipment, production assistance, and business management. This study uses qualitative, descriptive analysis, data collection with observation, interviews, and questionnaires. The results showed that the total number of active members was 24 people, 50% of the members specially cultivated the smoked fish that is the type of Catfish (Arius thalassinus) and Stingray (Dasyatis sp), while 45.83% of members processed boneless milkfish, and 4,17% produce salted fish. Increased average production scale of 31.82% in smoked fish business, 12.4% in boneless milkfish and 38.89% in salted fish business. Willingness to return capital in the good category, meaning that all members were able to carry out the schedule of relative payback on time. Approximately 83.3% of the group members felt that the program that followed had greatly assisted in increasing the scale of business but hoped to improve skills in terms of processing and marketing.

Arraias em rios da região Sudeste do Brasil: locais de ocorrência e impactos sobre a população Stingrays in rivers in southeastern Brazil: occurrence localities and impact on the population

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Domingos Garrone Neto

2010-02-01

Full Text Available INTRODUÇÃO: No presente trabalho objetivamos descrever o processo de colonização da Bacia do Alto Paraná, Sudeste do Brasil, por arraias, demonstrando sua atual situação e provável tendência, os impactos gerados e discutindo algumas ações de manejo e medidas mitigadoras. MÉTODOS: Foram realizadas entrevistas com ribeirinhos e profissionais de saúde para o levantamento de informações sobre a ocorrência de arraias e acidentes associados a estes animais, além de coletas e observações subaquáticas de potamotrigonídeos, entre 2004 e 2009, em localidades situadas nos Estados de São Paulo, Paraná e Mato Grosso do Sul, no Sudeste, Sul e parte do Centro-Oeste do Brasil. RESULTADOS: Três espécies de arraias foram identificadas na área de estudo, demonstrando utilizar os caminhos abertos pela Hidrovia Tietê-Paraná para se dispersarem. Dezesseis vítimas de acidentes envolvendo esses animais foram encontradas, notadamente banhistas e pescadores, chamando a atenção pelo fato dos casos não serem notificados e apresentarem elevada morbidade, com marcante incapacidade temporária para o trabalho. CONCLUSÕES: Este é o primeiro relato de invasão biológica envolvendo espécies de elasmobrânquios conhecido na literatura e, pelas arraias estarem colonizando áreas densamente povoadas e ampliando sua área de distribuição a cada ano, é de se esperar que sua interação negativa com humanos se intensifique, provocando alterações importantes no perfil epidemiológico dos acidentes por animais peçonhentos ocorridos no sudeste brasileiro.INTRODUCTION: In this paper, our aim was to describe the process of colonization of the upper Paraná basin, southeastern Brazil, by stingrays, showing the current situation, likely trend and impact caused and discussing some management actions and mitigation measures. METHODS: Interviews were held with riverbank people and health professionals, to gather information on occurrences of stingrays

Humoral immune response against native or 60Co irradiated venom and mucus from stingray Paratrygon aiereba

International Nuclear Information System (INIS)

Thomazi, Gabriela Ortega Coelho; Alves, Glaucie Jussilane; Aires, Raquel da Silva; Turibio, Thompson de Oliveira; Rocha, Andre Moreira; Spencer, Patrick Jack; Nascimento, Nanci do; Seibert, Carla Simone

2015-01-01

Poisonings and traumas caused by poisonous freshwater fish such as rays are considered a major public health problem and draw attention because of accidents involving these animals cause serious local symptoms and are disabling, keeping the victim away from work. The therapy of these cases is based only on the symptoms of patients, which implies in its low efficiency, causing suffering for the victims. This study aims to evaluate and compare the humoral immune response in animals inoculated with native or 60 Co irradiated Paratrygon aiereba venom and mucus. Ionizing radiation has proven to be an excellent tool to decrease the toxicity of venoms and isolated toxins. The mucus and venom samples of P. aiereba were irradiated using gamma rays from a 60 Co source. Animals models were immunized with the native or irradiated mucus or venom. The assays were conducted to assess the production of antibodies by the immunized animals using enzyme immunoassay and western blotting. Preliminary results show the production of antibodies by the immunized animals. The resulting sera were also checked for antigenic cross- reactivity between venom and mucus, demonstrating the potential of mucus as an antigen for serum production for the specific treatment for accidents by stingrays. However, it is essential to carry out further tests in order to verify the neutralization of the toxin by antibodies formed by animals. (author)

Humoral immune response against native or {sup 60}Co irradiated venom and mucus from stingray Paratrygon aiereba

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Thomazi, Gabriela Ortega Coelho; Alves, Glaucie Jussilane; Aires, Raquel da Silva; Turibio, Thompson de Oliveira; Rocha, Andre Moreira; Spencer, Patrick Jack; Nascimento, Nanci do, E-mail: 0916@prof.itpacporto.com.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Seibert, Carla Simone, E-mail: carlaseibert@yahoo.com [Universidade Federal do Tocantins (UFT), Porto Nacional, TO (Brazil)

2015-07-01

Poisonings and traumas caused by poisonous freshwater fish such as rays are considered a major public health problem and draw attention because of accidents involving these animals cause serious local symptoms and are disabling, keeping the victim away from work. The therapy of these cases is based only on the symptoms of patients, which implies in its low efficiency, causing suffering for the victims. This study aims to evaluate and compare the humoral immune response in animals inoculated with native or {sup 60}Co irradiated Paratrygon aiereba venom and mucus. Ionizing radiation has proven to be an excellent tool to decrease the toxicity of venoms and isolated toxins. The mucus and venom samples of P. aiereba were irradiated using gamma rays from a {sup 60}Co source. Animals models were immunized with the native or irradiated mucus or venom. The assays were conducted to assess the production of antibodies by the immunized animals using enzyme immunoassay and western blotting. Preliminary results show the production of antibodies by the immunized animals. The resulting sera were also checked for antigenic cross- reactivity between venom and mucus, demonstrating the potential of mucus as an antigen for serum production for the specific treatment for accidents by stingrays. However, it is essential to carry out further tests in order to verify the neutralization of the toxin by antibodies formed by animals. (author)

The Rapid Evolution of the Exciting Star of the Stingray Nebula

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Reindl, N.; Rauch, T.; Parthasarathy, M.; Werner, K.; Kruk, J.W.; Hamann, W. R.; Sander, A.; Todt, H.

2014-01-01

Context: SAO244567, the exciting star of the Stingray nebula, is rapidly evolving. Previous analyses suggested that it has heated up from an effective temperature of about 21 kK in 1971 to over 50 kK in the 1990s. Canonical post-asymptotic giant branch evolution suggests a relatively high mass while previous analyses indicate a low-mass star. Aims: A comprehensive model-atmosphere analysis of UV and optical spectra taken during 1988-2006 should reveal the detailed temporal evolution of its atmospheric parameters and provide explanations for the unusually fast evolution. Methods: Fitting line profiles from static and expanding non-LTE model atmospheres to the observed spectra allowed us to study the temporal change of effective temperature, surface gravity, mass-loss rate, and terminal wind velocity. In addition, we determined the chemical composition of the atmosphere. Results: We find that the central star has steadily increased its effective temperature from 38 kK in 1988 to a peak value of 60 kK in 2002. During the same time, the star was contracting, as concluded from an increase in surface gravity from log g = 4.8 to 6.0 and a drop in luminosity. Simultaneously, the mass-loss rate declined from log(M/M (solar mass) yr (exp -1)) = -9.0 to -11.6 and the terminal wind velocity increased from v (infinity) = 1800 km s (exp -1) to 2800 km s (exp -1). Since around 2002, the star stopped heating and has cooled down again to 55 kK by 2006. It has a largely solar surface composition with the exception of slightly subsolar carbon, phosphorus, and sulfur. The results are discussed by considering different evolutionary scenarios. Conclusions: The position of SAO244567 in the log T (sub eff) -log g plane places the star in the region of sdO stars. By comparison with stellar-evolution calculations, we confirm that SAO244567 must be a low-mass star (M nebula with a kinematical age of only about 1000 years. We speculate that the star could be a late He-shell flash object

Physical Properties of the Very Young PN Hen3-1357 (Stingray Nebula) Based on Multiwavelength Observations

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Otsuka, Masaaki [Institute of Astronomy and Astrophysics Academia Sinica, 11F of Astronomy-Mathematics Building, AS/NTU. No.1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan, R.O.C. (China); Parthasarathy, M. [Indian Institute of Astrophysics, II B lock Koramangala, Bangalore 560034, Karnataka (India); Tajitsu, A. [Subaru Telescope, National Astronomical Observatory of Japan, 650 N Aohoku Place, Hilo, HI 96720 (United States); Hubrig, S., E-mail: otsuka@asiaa.sinica.edu.tw [Leibniz-Institut fuer Astrophysik Potsdam (AIP) An der Sternwarte 12, D-14482 Potsdam (Germany)

2017-03-20

We carried out a detailed analysis of the interesting and important very young planetary nebula (PN) Hen3-1357 (Stingray Nebula) based on a unique data set of optical to far-IR spectra and photometric images. We calculated the abundances of nine elements using collisionally excited lines (CELs) and recombination lines (RLs). The RL C/O ratio indicates that this PN is O-rich, which is also supported by the detection of the broad 9/18 μ m bands from amorphous silicate grains. The observed elemental abundances can be explained by asymptotic giant branch (AGB) nucleosynthesis models for initially 1–1.5 M {sub ⊙} stars with Z = 0.008. The Ne overabundance might be due to the enhancement of {sup 22}Ne isotope in the He-rich intershell. Using the spectrum of the central star synthesized by Tlusty as the ionization/heating source of the PN, we constructed the self-consistent photoionization model with Cloudy to the observed quantities and derived the gas and dust masses, dust-to-gas mass ratio, and core mass of the central star. About 80% of the total dust mass is from warm–cold dust component beyond ionization front. Comparison with other Galactic PNe indicates that Hen3-1357 is an ordinary amorphous silicate-rich and O-rich gas PN. Among other studied PNe, IC4846 shows many similarities in properties of the PN to Hen3-1357, although their post-AGB evolution is quite different from each other. Further monitoring of observations and comparisons with other PNe such as IC4846 are necessary to understand the evolution of Hen3-1357.

ANÁLISIS DE LAS CAPTURAS DE TIBURONES Y RAYAS EN LAS PESQUERÍAS ARTESANALES DE TÁRCOLES, PACÍFICO CENTRAL DE COSTA RICA

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Andrés López Garro

2011-07-01

sharpnose shark (Rhizoprionodon longurio (6.9% and the scalloped hammerhead shark (Sphyrna lewini (6.1%. The longtail stingray (Dasyatis longa and the whitenose shark (Nasolamia velox represented the 3.5% and 2.6% of the total catch, respectively.  During 75 fishing trips, we analyzed 6.458 fish individuals, of them only 4.4% (240 individuals were sharks and longtail stingrays. Among these, M. henlei was also the most abundant species (50.4%, followed by R. longurio (21.7%, D. longa (13.8%, N. velox (5.8%, S. lewini (5.8%, and M. lunulatus (2.5%. Considering the seasonality and abundance of smooth hound sharks in Herradura, we recommend a technical closure during the higher catch months (January-February and September-October. Also, we recommend protecting the Peñón, which is inhabited by adults of longtail stingray and juvenile scalloped hammerhead sharks.

Elasmobranchs observed in deepwaters (45-330m at Isla del Coco National Park, Costa Rica (Eastern Tropical Pacific

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Jorge Cortés

2012-11-01

Full Text Available Isla del Coco is an oceanic island 500km off the Pacific coast of Costa Rica. It is a National Park and its marine fauna has been relatively well protected. The island is famous for its elasmobranch (sharks, rays and skates sightings in shallow waters. Here we present a catalogue of the deepwater elasmobranchs observed with the DeepSee submersible. Five species of sharks, six species of skates and one ray have been observed between 45 and 330m depth. Triaenodon obesus, the white tip reef shark, was commonly observed between 80 and 301m, but only in the afternoons. Sphyrna lewini, the scalloped hammerhead shark, was observed as deep a 303m, but commonly between 45 and 90m, and close to the island. Odontaspis ferox, the smalltooth sand tiger shark, was observed between 82 and 316m. Echinorhinus cookei, the prickly shark, was observed between 91 and 320m. Rhincodon typus, the whale shark, was observed only close to the island, between 77 and 80m. Taeniura meyeni, the marbled ray, was observed only close to the island, between 45 and 90m. A Dasyatis sp., similar to the the diamond stingray, was observed only once close to the island at 60m; this is the first report of this genus at Isla del Coco National Park. Manta birostris, the giant manta, was only observed close to the island at 90m. Mobula tarapacana, the sicklefin devil ray, was observed between 60 and 326m, extending its maximum depth almost 10 times what has been reported. Aetobatus narinari, the spotted eagle ray, was observed only close to the island between 60 and 82m. Torpedo peruana, the Peruvian torpedo ray, was observed only once at 313m, and is the first record of this species from Isla del Coco National Park.

Necrosis cutánea severa por picadura de raya en el miembro inferior: presentación de un caso y revisión de la literatura Stingray injury causing severe cutaneous necrosis: case report and literature review

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M.A. Hoyos Franco

2009-12-01

Full Text Available El propósito de este trabajo es presentar nuestra experiencia con un caso de picadura por raya en el área maleolar interna del pie derecho de un hombre de 25 años, que sufrió mientras pescaba. Inicialmente presentó dolor urente, seguido de edema severo, con necrosis de la piel suprayacente. Ingresa a nuestra institución 24 horas después y con edema, eritema y secreción purulenta en el sitio afectado. Se inicia tratamiento con antibióticos sistémicos y se realizan tres lavados y desbridamientos en días subsecuentes. Evolucionó con solución de continuidad y exposición ósea sobre el maléolo interno en un área de 7 x 5 cms que se cubrió con un colgajo safeno interno de flujo reverso que evolucionó satisfactoriamente. Las lesiones ocasionadas por la picadura de raya (Myliobatidae son escasamente referidas en Cirugía Plástica, pues la lesión tisular severa de las extremidades es poco frecuente. Revisamos la fisiopatología, los tipos de lesiones que se producen y los principios de tratamiento.The purpose of this paper is to present our experience with one case of stingray injury, in a 25 years old man, while he was fishing, compromising his right feet at the internal malleolus. At the beginning he had severe pain, and during the first hours after the accident progressive edema was evident. He arrived to our hospital 24 hours later, when purulent discharge and eritem was obvious. Intravenous antibiotics were initiated and three surgical debridements where performed during the following week. After the process was complete, a soft tissue defect was created on the internal malleolus (7 x 5 cm. Reconstruction was achieved using a reverse internal saphenous flap that evolved satisfactorily. Severe skin injuries caused by stingrays (Myliobatidae have been reported shortly in plastic surgery literature, because these lesions usually heal without surgical procedures. We review skin injury physiopathology, showing the different kind of

Bioaccumulation of organohalogenated compounds in sharks and rays from the southeastern USA.

Science.gov (United States)

Weijs, Liesbeth; Briels, Nathalie; Adams, Douglas H; Lepoint, Gilles; Das, Krishna; Blust, Ronny; Covaci, Adrian

2015-02-01

Organohalogenated compounds are widespread in the marine environment and can be a serious threat to organisms in all levels of aquatic food webs, including elasmobranch species. Information about the concentrations of POPs (persistent organic pollutants) and of MeO-PBDEs (methoxylated polybrominated diphenyl ethers) in elasmobranchs is scarce and potential toxic effects are poorly understood. The aims of the present study were therefore to investigate the occurrence of multiple POP classes (PCBs, PBDEs, DDXs, HCB, CHLs) and of MeO-PBDEs in various elasmobranch species from different trophic levels in estuarine and marine waters of the southeastern United States. Overall, levels and patterns of PCBs, PBDEs, DDXs, HCB, CHLs and of MeO-PBDEs varied according to the species, maturity stage, gender and habitat type. The lowest levels of POPs were found in Atlantic stingrays and the highest levels were found in bull sharks. As both species are respectively near the bottom and at top of the trophic web, with juvenile bull sharks frequently feeding on Atlantic stingrays, these findings further suggest a bioaccumulation and biomagnification process with trophic position. MeO-PBDEs were not detected in Atlantic stingrays, but were found in all shark species. HCB was not found in Atlantic stingrays, bonnetheads or lemon sharks, but was detected in the majority of bull sharks examined. Comparison with previous studies suggests that Atlantic stingrays may be experiencing toxic effects of PCBs and DDXs on their immune system. However, the effect of these compounds on the health of shark species remains unclear. Copyright © 2014 Elsevier Inc. All rights reserved.

The 5S rDNA family evolves through concerted and birth-and-death evolution in fish genomes: an example from freshwater stingrays

Science.gov (United States)

2011-01-01

Background Ribosomal 5S genes are well known for the critical role they play in ribosome folding and functionality. These genes are thought to evolve in a concerted fashion, with high rates of homogenization of gene copies. However, the majority of previous analyses regarding the evolutionary process of rDNA repeats were conducted in invertebrates and plants. Studies have also been conducted on vertebrates, but these analyses were usually restricted to the 18S, 5.8S and 28S rRNA genes. The recent identification of divergent 5S rRNA gene paralogs in the genomes of elasmobranches and teleost fishes indicate that the eukaryotic 5S rRNA gene family has a more complex genomic organization than previously thought. The availability of new sequence data from lower vertebrates such as teleosts and elasmobranches enables an enhanced evolutionary characterization of 5S rDNA among vertebrates. Results We identified two variant classes of 5S rDNA sequences in the genomes of Potamotrygonidae stingrays, similar to the genomes of other vertebrates. One class of 5S rRNA genes was shared only by elasmobranches. A broad comparative survey among 100 vertebrate species suggests that the 5S rRNA gene variants in fishes originated from rounds of genome duplication. These variants were then maintained or eliminated by birth-and-death mechanisms, under intense purifying selection. Clustered multiple copies of 5S rDNA variants could have arisen due to unequal crossing over mechanisms. Simultaneously, the distinct genome clusters were independently homogenized, resulting in the maintenance of clusters of highly similar repeats through concerted evolution. Conclusions We believe that 5S rDNA molecular evolution in fish genomes is driven by a mixed mechanism that integrates birth-and-death and concerted evolution. PMID:21627815

Some preliminary notes on Surinam Sting Rays, including the description of a new species

NARCIS (Netherlands)

Boeseman, M.

1948-01-01

In Dr. D. C. Geijskes' collection of Surinam fishes, mentioned in my previous paper on this subject (Boeseman, 1948), I found six specimens belonging to the so-called "sting rays" (Dasyatidae), representing three different species, and all very interesting in some respects. I. Dasyatis schmardae

Community structure of elasmobranchs in estuaries along the northwest Gulf of Mexico

Science.gov (United States)

Plumlee, Jeffrey D.; Dance, Kaylan M.; Matich, Philip; Mohan, John A.; Richards, Travis M.; TinHan, Thomas C.; Fisher, Mark R.; Wells, R. J. David

2018-05-01

Estuaries promote high levels of productivity and biodiversity by providing habitat for many biological communities due to their wide range of environmental conditions. Estuarine systems serve as nurseries, areas for parturition, and feeding grounds for elasmobranchs. However, estuaries face an array of anthropogenic pressures, including overfishing, altered flow regimes, pollution, and habitat destruction. Given the vulnerability of estuarine ecosystems, observing long-term changes in community structure is essential to understanding the effects of anthropogenic stressors. Elasmobranch community structure was analyzed among eight estuaries in the northwest Gulf of Mexico to evaluate spatial and temporal variability in species abundance and diversity using bi-annual fisheries independent gillnet survey data over three decades (1985-2014). Ten species comprised 99.4% of elasmobranchs caught which included 35.3% bull sharks (Carcharhinus leucas), 18.1% bonnetheads (Sphyrna tiburo), 17.0% cownose rays (Rhinoptera bonasus), 13.4% blacktip sharks (Carcharhinus limbatus), 5.9% Atlantic stingrays (Dasyatis sabina), 3.1% Atlantic sharpnose sharks (Rhizoprionodon terraenovae), 2.7% spinner sharks (Carcharhinus brevipinna), 2.1% scalloped hammerheads (Sphyrna lewini), 1.7% finetooth sharks (Carcharhinus isodon), and 0.7% lemon sharks (Negaprion brevirostris). During the study period, elasmobranch community structure changed among estuaries and among decades. Bull sharks, bonnetheads, cownose rays, blacktip sharks, and spinner sharks all increased in abundance during the study period, whereas finetooth sharks and lemon sharks decreased over time. Higher latitude estuaries were dominated by bull sharks while lower latitude estuaries were dominated by cownose rays. Salinity was the most important environmental variable in predicting individual elasmobranch species abundance (deviance explained: 14.4 ± 6.5 SD), while temperature and depth also played a role in shaping community

Blood culture results from healthy captive and free-ranging elasmobranchs.

Science.gov (United States)

Mylniczenko, Natalie D; Harris, Brigita; Wilborn, Rachel E; Young, Forrest A

2007-09-01

Blood culture is a diagnostic tool used in confirming bacterial disease in teleostean and elasmobranch fishes. Unlike teleosts, elasmobranchs have a normal microflora in multiple organs, but their blood has generally been considered to be sterile. In regular exams of elasmobranchs conducted at a public aquarium, occasional blood samples have tested positive on culture. This finding prompted a blood culture survey of healthy captive and wild elasmobranchs (sharks and stingrays), which showed that 26.7% of all animals were positive. Stingrays alone showed a 50% occurrence of positive blood cultures, although the total number of animals was low and freshwater species were included in this number. When elasmobranchs other than stingrays were evaluated according to metabolic category, pelagic animals had a higher percentage of positive cultures than nonpelagic animals (38.7% versus 13.9%). These results indicate that a single positive blood culture without other corroborating diagnostics is not sufficient to confirm septicemia in elasmobranchs.

Rancang bangun industri penyamakan kulit ikan pari

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Sri Untari

2004-07-01

Full Text Available Stingray fish potential in Indonesia is big enough but has not yet been exploited maximally, only some area like Lampung which is already exploiting the stingray leather tanning them and sell to Java. From the result of the research, stringray leather could pieces the big enough advantage that was at the price of selling Rp. 68.000,- per pieces pay back periode in average, would obtain the advange before the tax Rp. 285.649.697,- peryear and the advantage after the tax Rp. 228.519.757,- per year, pay back periode before the tax was in 1 year and 10 months and back periode after the tax was in 2 years and 2 month. As for break event point 35.04% with the value Rp. 978.385.533,- with break event value point capacitie production 14.388 pieces per year. Based on the result of the calculation of investments criteria was NPV (net present value = Rp. 162.570.834,- (greater tan zero while IRR = 30,54% greater than SOCC (DF = 18% from the pay back periode = 2 year 1 month. Therefore from the market analysis and the production aspect, the effect of leather industry of stingray fish is so feasible that is competent to be developed in some areas having big potential stingray fish in Indonesia, so that it can improve the working opportunity and the effort for all of fishermen and their family.

Myological variability in a decoupled skeletal system: batoid cranial anatomy.

Science.gov (United States)

Kolmann, Matthew A; Huber, Daniel R; Dean, Mason N; Grubbs, R Dean

2014-08-01

Chondrichthyans (sharks, batoids, and chimaeras) have simple feeding mechanisms owing to their relatively few cranial skeletal elements. However, the indirect association of the jaws to the cranium (euhyostylic jaw suspension) has resulted in myriad cranial muscle rearrangements of both the hyoid and mandibular elements. We examined the cranial musculature of an abbreviated phylogenetic representation of batoid fishes, including skates, guitarfishes and with a particular focus on stingrays. We identified homologous muscle groups across these taxa and describe changes in gross morphology across developmental and functional muscle groups, with the goal of exploring how decoupling of the jaws from the skull has effected muscular arrangement. In particular, we focus on the cranial anatomy of durophagous and nondurophagous batoids, as the former display marked differences in morphology compared to the latter. Durophagous stingrays are characterized by hypertrophied jaw adductors, reliance on pennate versus fusiform muscle fiber architecture, tendinous rather than aponeurotic muscle insertions, and an overall reduction in mandibular kinesis. Nondurophagous stingrays have muscles that rely on aponeurotic insertions onto the skeletal structure, and display musculoskeletal specialization for jaw protrusion and independent lower jaw kinesis, relative to durophagous stingrays. We find that among extant chondrichthyans, considerable variation exists in the hyoid and mandibular muscles, slightly less so in hypaxial muscles, whereas branchial muscles are overwhelmingly conserved. As chondrichthyans occupy a position sister to all other living gnathostomes, our understanding of the structure and function of early vertebrate feeding systems rests heavily on understanding chondrichthyan cranial anatomy. Our findings highlight the incredible variation in muscular complexity across chondrichthyans in general and batoids in particular. © 2014 Wiley Periodicals, Inc.

Fishers' knowledge on the coast of Brazil.

Science.gov (United States)

Begossi, Alpina; Salivonchyk, Svetlana; Lopes, Priscila F M; Silvano, Renato A M

2016-06-01

Although fishers' knowledge has been recently considered into management programmes, there is still the need to establish a better understanding of fishers' perceptions and cognition. Fishers can provide novel information on the biology and ecology of species, which can potentially be used in the management of fisheries. The knowledge fishers have and how they classify nature is empirically based. It is common, for example, to observe that fishers' taxonomy is often represented by the generic level, one of the hierarchical categories of folk classification that is somewhat analogous to the Linnean genus, as it groups organisms of a higher rank than the folk species.In this study we compiled the knowledge fishers have on local fish, such as their folk names, diet and habitat. Five coastal communities widely distributed along the Brazilian coast were studied: two from the northeast (Porto Sauípe and Itacimirim, in Bahia State, n of interviewees = 34), two from the southeast (Itaipu at Niterói and Copacabana at Rio de Janeiro, Rio de Janeiro State, n = 35) and one from the south coast (Pântano do Sul, in Santa Catarina State, n = 23). Fish pictures were randomly ordered and the same order was presented to all interviewees (n = 92), when they were then asked about the species name and classification and its habitat and diet preferences. Fishers make clusters of fish species, usually hierarchically; fishers of the coast of Brazil use mostly primary lexemes (generic names) to name fish; and fishers did not differentiate between scientific species, since the same folk generic name included two different scientific species. Fishers provide information on species to which there is scarce or no information on diet and habitat, such as Rhinobatos percellens (chola guitarfish, arraia viola or cação viola), Sphoeroides dorsalis (marbled puffer, baiacu), Mycteroperca acutirostris (comb grouper, badejo) and Dasyatis guttata (longnose stingray, arraia, arraia

Amplitude Effects on Thrust Production for Undulatory Swimmers

Science.gov (United States)

Gater, Brittany; Bayandor, Javid

2017-11-01

Biological systems offer novel and efficient solutions to many engineering applications, including marine propulsion. It is of interest to determine how fish interact with the water around them, and how best to utilize the potential their methods offer. A stingray-like fin was chosen for analysis due to the maneuverability and versatility of stingrays. The stingray fin was modeled in 2D as a sinusoidal wave with an amplitude increasing from zero at the leading edge to a maximum at the trailing edge. Using this model, a parametric study was performed to examine the effects of the fin on surrounding water in CFD simulations. The results were analyzed both qualitatively, in terms of the pressure contours on the fin and vorticity in the trailing wake, and quantitatively, in terms of the resultant forces on the fin. The amplitude was found to have no effect on the average thrust during steady swimming, when the wave speed on the fin was approximately equal to the swimming speed. However, amplitude was shown to have a significant effect on thrust production when the fin was accelerating. This finding suggests that for undulatory swimmers, amplitude is less useful for controlling swimming speed, but can be used to great effect for augmenting thrust during acceleration.

Browse Title Index

African Journals Online (AJOL)

Items 451 - 500 of 1060 ... ... as a non-lethal method for stingray (Myliobatiformes) diet sampling, Abstract .... Semaeostomeae) along the Mediterranean coast of Tunisia, Abstract ... RJ Anderson, F Dufois, M Rouault, PW Froneman, AK Whitfield, ...

Elasmobranchs observed in deepwaters (45-330m at Isla del Coco National Park, Costa Rica (Eastern Tropical Pacific

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Jorge Cortés

2012-11-01

Full Text Available Isla del Coco is an oceanic island 500km off the Pacific coast of Costa Rica. It is a National Park and its marine fauna has been relatively well protected. The island is famous for its elasmobranch (sharks, rays and skates sightings in shallow waters. Here we present a catalogue of the deepwater elasmobranchs observed with the DeepSee submersible. Five species of sharks, six species of skates and one ray have been observed between 45 and 330m depth. Triaenodon obesus, the white tip reef shark, was commonly observed between 80 and 301m, but only in the afternoons. Sphyrna lewini, the scalloped hammerhead shark, was observed as deep a 303m, but commonly between 45 and 90m, and close to the island. Odontaspis ferox, the smalltooth sand tiger shark, was observed between 82 and 316m. Echinorhinus cookei, the prickly shark, was observed between 91 and 320m. Rhincodon typus, the whale shark, was observed only close to the island, between 77 and 80m. Taeniura meyeni, the marbled ray, was observed only close to the island, between 45 and 90m. A Dasyatis sp., similar to the the diamond stingray, was observed only once close to the island at 60m; this is the first report of this genus at Isla del Coco National Park. Manta birostris, the giant manta, was only observed close to the island at 90m. Mobula tarapacana, the sicklefin devil ray, was observed between 60 and 326m, extending its maximum depth almost 10 times what has been reported. Aetobatus narinari, the spotted eagle ray, was observed only close to the island between 60 and 82m. Torpedo peruana, the Peruvian torpedo ray, was observed only once at 313m, and is the first record of this species from Isla del Coco National Park.La Isla del Coco es una isla oceánica a 500km de la costa Pacífica de Costa Rica. Es un Parque Nacional donde la fauna marina ha estado relativamente bien protegida. La isla es famosa por los elasmobranquios (tiburones y rayas en aguas poco profundas. Aquí presentamos un cat

Horror Haapsalus / Kaisa Karu

Index Scriptorium Estoniae

Karu, Kaisa

2010-01-01

23.-25. aprillini Haapsalus toimuva 5. Haapsalu Õudus- ja Fantaasiafilmide festivali (HÕFF) filmidest: režissööride Yannick Dahan'i ja Benjamin Rocher "Hord", Srdjan Spasojevic'i "Serbia film", Cory McAbee "Stingray Sam", režissöör Tom Six' "Inimsajajalgne", Shinya Tsukamoto "Tetsuo"

Prey handling using whole-body fluid dynamics in batoids.

Science.gov (United States)

Wilga, Cheryl D; Maia, Anabela; Nauwelaerts, Sandra; Lauder, George V

2012-02-01

Fluid flow generated by body movements is a foraging tactic that has been exploited by many benthic species. In this study, the kinematics and hydrodynamics of prey handling behavior in little skates, Leucoraja erinacea, and round stingrays, Urobatis halleri, are compared using kinematics and particle image velocimetry. Both species use the body to form a tent to constrain the prey with the pectoral fin edges pressed against the substrate. Stingrays then elevate the head, which increases the volume between the body and the substrate to generate suction, while maintaining pectoral fin contact with the substrate. Meanwhile, the tip of the rostrum is curled upwards to create an opening where fluid is drawn under the body, functionally analogous to suction-feeding fishes. Skates also rotate the rostrum upwards although with the open rostral sides and the smaller fin area weaker fluid flow is generated. However, skates also use a rostral strike behavior in which the rostrum is rapidly rotated downwards pushing fluid towards the substrate to potentially stun or uncover prey. Thus, both species use the anterior portion of the body to direct fluid flow to handle prey albeit in different ways, which may be explained by differences in morphology. Rostral stiffness and pectoral fin insertion onto the rostrum differ between skates and rays and this corresponds to behavioral differences in prey handling resulting in distinct fluid flow patterns. The flexible muscular rostrum and greater fin area of stingrays allow more extensive use of suction to handle prey while the stiff cartilaginous rostrum of skates lacking extensive fin insertion is used as a paddle to strike prey as well as to clear away sand cover. Copyright © 2011 Elsevier GmbH. All rights reserved.

Record of the freshwater stingrays Potamotrygon brachyura and P. motoro (Chondrichthyes, Potamotrygonidae in the lower Uruguay river, South America Registro das raias de água doce Potamotrygon brachyura e P. motoro (Potamotrygonidae no baixo rio Uruguai, America do Sul

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María Cristina Oddone

2012-06-01

Full Text Available Freshwater stingrays, or potamotrygonids, are restricted to Neotropical river drainages. These elasmobranchs are well adapted to freshwater environments and the number of described species gradually increases as further research is carried out. Some of the first studies on their systematics and natural history were carried out in the 1960s and 1970s in southern South America. However, there is no new published data on potamotrygonids from Uruguayan waters since then (except for local journal reports from sportive fishermen and specimens deposited in Uruguayan collections. The present study aims to record the recent occurrence of two species of potamotrygonids caught by sport fishermen, with comments on other published historical records for the same area. As many other elasmobranchs, these species have an important, but not always well understood, role in the Uruguayan rivers ecosystems.As raias de água doce ou potamotrigonídeos estão restritas às drenagens dos rios Neotropicais. Estas raias tem se adaptado bem aos ambientes de água doce e o número de espécies descritas aumenta gradualmente conforme as pesquisas na área se intensificam. Alguns dos primeiros estudos sobre a sistemática e a historia natural deste grupo foram realizados nas décadas de 1960 e 1970 na região Sul de América do Sul. Porém, há poucos dados publicados sobre potamotrigonídeos em águas uruguaias desde então (com exceção de registros de pescadores esportivos publicados em jornais locais, e espécimes depositados em coleções uruguaias. O presente estudo, portanto, tem como objetivo registrar a ocorrência de duas espécies de potamotrigonídeos no Uruguai capturados por pescadores esportivos assim como realizar uma compilação de ocorrências anteriores presentes na literatura. Como muitos outros elasmobrânquios, estas espécies possuem um papel importante nos ecossistemas dos rios uruguaios, embora não completamente compreendido.

Metabolic organization of freshwater, euryhaline, and marine elasmobranchs: implications for the evolution of energy metabolism in sharks and rays.

Science.gov (United States)

Speers-Roesch, B; Ip, Y K; Ballantyne, J S

2006-07-01

To test the hypothesis that the preference for ketone bodies rather than lipids as oxidative fuel in elasmobranchs evolved in response to the appearance of urea-based osmoregulation, we measured total non-esterified fatty acids (NEFA) in plasma as well as maximal activities of enzymes of intermediary metabolism in tissues from marine and freshwater elasmobranchs, including: the river stingray Potamotrygon motoro (shark Chiloscyllium punctatum (>300 mmol l(-1) plasma urea); and the euryhaline freshwater stingray Himantura signifer, which possesses intermediate levels of urea. H. signifer also were acclimated to half-strength seawater (15 per thousand) for 2 weeks to ascertain the metabolic effects of the higher urea level that results from salinity acclimation. Our results do not support the urea hypothesis. Enzyme activities and plasma NEFA in salinity-challenged H. signifer were largely unchanged from the freshwater controls, and the freshwater elasmobranchs did not show an enhanced capacity for extrahepatic lipid oxidation relative to the marine species. Importantly, and contrary to previous studies, extrahepatic lipid oxidation does occur in elasmobranchs, based on high carnitine palmitoyl transferase (CPT) activities in kidney and rectal gland. Heart CPT in the stingrays was detectable but low, indicating some capacity for lipid oxidation. CPT was undetectable in red muscle, and almost undetectable in heart, from C. punctatum as well as in white muscle from T. lymma. We propose a revised model of tissue-specific lipid oxidation in elasmobranchs, with high levels in liver, kidney and rectal gland, low or undetectable levels in heart, and none in red or white muscle. Plasma NEFA levels were low in all species, as previously noted in elasmobranchs. D-beta-hydroxybutyrate dehydrogenase (d-beta-HBDH) was high in most tissues confirming the importance of ketone bodies in elasmobranchs. However, very low d-beta-HBDH in kidney from T. lymma indicates that interspecific

Batoid locomotion: effects of speed on pectoral fin deformation in the little skate, Leucoraja erinacea.

Science.gov (United States)

Di Santo, Valentina; Blevins, Erin L; Lauder, George V

2017-02-15

Most batoids have a unique swimming mode in which thrust is generated by either oscillating or undulating expanded pectoral fins that form a disc. Only one previous study of the freshwater stingray has quantified three-dimensional motions of the wing, and no comparable data are available for marine batoid species that may differ considerably in their mode of locomotion. Here, we investigate three-dimensional kinematics of the pectoral wing of the little skate, Leucoraja erinacea , swimming steadily at two speeds [1 and 2 body lengths (BL) s -1 ]. We measured the motion of nine points in three dimensions during wing oscillation and determined that there are significant differences in movement amplitude among wing locations, as well as significant differences as speed increases in body angle, wing beat frequency and speed of the traveling wave on the wing. In addition, we analyzed differences in wing curvature with swimming speed. At 1 BL s -1 , the pectoral wing is convex in shape during the downstroke along the medio-lateral fin midline, but at 2 BL s -1 the pectoral fin at this location cups into the flow, indicating active curvature control and fin stiffening. Wing kinematics of the little skate differed considerably from previous work on the freshwater stingray, which does not show active cupping of the whole fin on the downstroke. © 2017. Published by The Company of Biologists Ltd.

Three new species of Merizocotyle Cerfontaine, 1894 (Monogenea: Monocotylidae) from the nasal tissues of dasyatid rays collected off Malaysian and Indonesian Borneo.

Science.gov (United States)

Chisholm, Leslie A; Whittington, Ian D

2012-06-01

Three new species of Merizocotyle Cerfontaine, 1894 (Monogenea: Monocotylidae) are described from the nasal tissues of stingrays collected off Borneo. Merizocotyle macrostrobus n. sp. is described from the dwarf whipray Himantura walga (Müller & Henle) collected in shallow waters off Sematan, Sarawak, Malaysia. This species can be distinguished from the other members of the genus by the morphology of the sclerotised male copulatory organ, which is long with many twists and loops. The vaginae of this species are also long and looped. Merizocotyle papillae n. sp. is described from the roughnose stingray Pastinachus solocirostris Last, Manjaji & Yearsley collected off Sematan and Mukah, Sarawak, Malaysia. It is distinguished from the other species of Merizocotyle by the morphology of the male copulatory organ, which is a sclerotised tube that expands slightly and then tapers at the distal end, and by the presence of papillae on the dorsal edge of the haptor. Merizocotyle rhadinopeos n. sp. is described from the whitenose whip ray Himantura uarnacoides (Bleeker) collected off Manggar, East Kalimantan, Indonesia. It can be differentiated by the male copulatory organ, which is a short, narrow, curved, sclerotised tube tapering distally, and the path of the ovary, which runs anteriorly to the base of the oötype. We also provide details of new host and/or locality records for M. australensis (Beverley-Burton & Williams, 1989) Chisholm, Wheeler & Beverley-Burton, 1995, M. icopae Beverley-Burton & Williams, 1989 and M. pseudodasybatis (Hargis, 1955) Chisholm, Wheeler & Beverley-Burton, 1995.

Suvised sportautod / Robert Koistinen, Aimo Niemi

Index Scriptorium Estoniae

Koistinen, Robert

2014-01-01

TM võrdleb: Abarth 595 Competizion, Alfa Romeo 4C, Audi S1 Sportback, Audi S3 Sedan, Audi RS Q3, BMW M235i, BMW M3, BMW M4, Chevrolet Corvette C7 Stingray, Jaguar F-Type R Coupé, Lamborghini Huracán LP 610-4, McLaren 650S Spider, Mercedes-Benz A 45 AMG, Mini Cooper S, Peugeot RCZ, R Porsche 911 Turbo S, Porsche Macan Turbo, Seat Leon SC Cupra, Subaru WRX STI, Toyota GT86 TRD, Volkswagen Golf R, Volkswagen Polo R WRC

The 1986 ARI (Army Research Institute) Survey of U.S. Army Recruits: Media Habits

Science.gov (United States)

1988-04-01

EDGAR M. JOHNSONCOI Technical Director Cmadn Technical review by Accesion For Curtis L. Gilroy NTAS CRA&:AI Laurel N. Oliver DI A UnC ABm~jc NOTICES...NBC SOURCE T681 X240 SOLID GOLD X241 SOUL TRAIN X242 AMERICAN BANDSTAND X243 DANCE FEVER U" X244 MOVIES ON NETWORK TV X755 MUSIC VIDEOS (NOT...BLACKE’S MAGIC Y080 MOONLIGHTING Y081 MACGIVER Y082 STINGRAY Y083 AIRWOLF Y084 THE A-TEAM Y085 HUNTER Y086 MIAMI VICE Y087 HARDCASTLE AND MCCORMICK Y088

The use of pelvic fins for benthic locomotion during foraging behavior in Potamotrygon motoro (Chondrichthyes: Potamotrygonidae

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Akemi Shibuya

2015-06-01

Full Text Available Synchronized bipedal movements of the pelvic fins provide propulsion (punting during displacement on the substrate in batoids with benthic locomotion. In skates (Rajidae this mechanism is mainly generated by the crural cartilages. Although lacking these anatomical structures, some stingray species show modifications of their pelvic fins to aid in benthic locomotion. This study describes the use of the pelvic fins for locomotory performance and body re-orientation in the freshwater stingray Potamotrygon motoro (Müller & Henle, 1841 during foraging. Pelvic fin movements of juvenile individuals of P. motoro were recorded in ventral view by a high-speed camera at 250-500 fields/s-1. Potamotrygon motoro presented synchronous, alternating and unilateral movements of the pelvic fins, similar to those reported in skates. Synchronous movements were employed during straightforward motion for pushing the body off the substrate as well as for strike feeding, whereas unilateral movements were used to maneuver the body to the right or left during both locomotion and prey capture. Alternating movements of the pelvic fins are similar to bipedal movements in terrestrial and semi-aquatic tetrapods. The pelvic fins showed coordinated movements during feeding even when stationary, indicating that they have an important function in maintaining body posture (station holding during prey capture and manipulation. The use of pelvic fins during prey stalking may be advantageous because it results in less substrate disturbance when compared to movements generated by pectoral fin undulation. The range of pelvic fin movements indicates more complex control and coordination of the pelvic radial muscles.

Observations of marine wildlife tourism effects on a non-focal species.

Science.gov (United States)

Rizzari, J R; Semmens, J M; Fox, A; Huveneers, C

2017-09-01

A radio-acoustic positioning system was used to assess the effects of shark cage-diving operators (SCDO) on the fine-scale movements of a non-focal species, the smooth stingray Bathytoshia brevicaudata. The results revealed that the time spent in the array was individually variable, but generally increased when SCDO were present and that the presence of SCDO may have the capacity to elicit changes in the space use of B. brevicaudata. These results indicate that the effects of marine wildlife tourism may extend beyond the focal species of interest. © 2017 The Fisheries Society of the British Isles.

APORTES A LA BIOLOGÍA DE TIBURONES Y RAYAS DEMERSALES EN LA REGIÓN NORTE DEL CARIBE COLOMBIANO

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Fabian Moreno

2008-09-01

Full Text Available El presente estudio es una contribución al conocimiento biológico de los peces cartilaginosos en la región norte del Caribe colombiano. Los ejemplares examinados se capturaron con una red demersal, se determinó su peso, longitud total y estado de madurez sexual. Adicionalmente se realizó la ubicación espacial de las capturas y la relación con las variables ambientales. Se capturaron un total de 21 individuos, colectando tres especies de rayas, Dasyatis americana, D. guttata y Rhinobatos percellens, dos de tiburones Mustelus minicanis y Rhizoprionodon porosus, la más común fue D. guttata con 56%, las tallas (longitud total fluctuaron entre los 1.760 - 394 mm en rayas y 595 - 585 mm en tiburones. Se obtuvieron más hembras que machos para todas las especies, con predominio de estados inmaduros y en maduración, solo se registró una hembra grávida deM. Minicanis con dos embriones.

Records of new and rare elasmobranchs from Taiwan.

Science.gov (United States)

Hsu, Hua Hsun; Joung, Shoou Jeng; Ebert, David A; Lin, Chia Yen

2013-01-01

Five new records of elasmobranchs collected from eastern Taiwan fish markets, Da-xi and Cheng-gong, are presented. Samples were caught by deepsea longliners and bottom trawlers which operate in northeastern waters off Taiwan between 2004 and 2012. These five new species records include the smalltooth sandtiger, Odontaspis ferox (Risso, 1810) (Lamniformes: Odontaspididae), salamander shark, Parmaturus pilosus Garman, 1906 (Carcharhiniformes: Scyliorhinidae), leadhued skate Notoraja tobitukai (Hiyama, 1940) (Rajiformes: Arhynchobatidae), giant skate Dipturus gigas (Ishiyama, 1958) (Rajiformes: Rajidae), and the pelagic stingray Pteroplatytrygon violacea (Bonaparte, 1832) (Myliobatiformes: Dasyatidae), Diagnostic characteristics for each species are given and a key to the genera Parmaturus and Dipturus from Taiwan is presented.

Field hearing measurements of the Atlantic sharpnose shark Rhizoprionodon terraenovae.

Science.gov (United States)

Casper, B M; Mann, D A

2009-12-01

Field measurements of hearing thresholds were obtained from the Atlantic sharpnose shark Rhizoprionodon terraenovae using the auditory evoked potential method (AEP). The fish had most sensitive hearing at 20 Hz, the lowest frequency tested, with decreasing sensitivity at higher frequencies. Hearing thresholds were lower than AEP thresholds previously measured for the nurse shark Ginglymostoma cirratum and yellow stingray Urobatis jamaicensis at frequencies sharks which have been observed in acoustic field attraction experiments. The sound pressure levels that would be equivalent to the particle acceleration thresholds of R. terraenovae were much higher than the sound levels which attracted closely related sharks suggesting a discrepancy between the hearing threshold experiments and the field attraction experiments.

Outsourcing neural active control to passive composite mechanics: a tissue engineered cyborg ray

Science.gov (United States)

Gazzola, Mattia; Park, Sung Jin; Park, Kyung Soo; Park, Shirley; di Santo, Valentina; Deisseroth, Karl; Lauder, George V.; Mahadevan, L.; Parker, Kevin Kit

2016-11-01

Translating the blueprint that stingrays and skates provide, we create a cyborg swimming ray capable of orchestrating adaptive maneuvering and phototactic navigation. The impossibility of replicating the neural system of batoids fish is bypassed by outsourcing algorithmic functionalities to the body composite mechanics, hence casting the active control problem into a design, passive one. We present a first step in engineering multilevel "brain-body-flow" systems that couple sensory information to motor coordination and movement, leading to behavior. This work paves the way for the development of autonomous and adaptive artificial creatures able to process multiple sensory inputs and produce complex behaviors in distributed systems and may represent a path toward soft-robotic "embodied cognition".

Hábitos alimentares e sobreposição trófica das raias Potamotrygon falkneri e Potamotrygon motoro (Chondrichthyes, Potamotrygonidae na planície alagável do alto rio Paraná, Brasil = Feeding habitats and trophic overlap of the freshwater stingrays Potamotrygon falkneri e Potamotrygon motoro (Chondrichthyes, Potamotrygonidae in the upper Paraná river floodplain, Brazil

Directory of Open Access Journals (Sweden)

Milza Celi Fedatto Abelha

2006-07-01

Full Text Available As raias Potamotrygon falkneri e Potamotrygon motoro foram avaliadas em relação à composição de suas dietas e a sobreposição do nicho trófico nos períodos de seca (agosto/2004 e cheia (janeiro/2005 na planície alagável do alto rio Paraná, em três estações de coleta próximas à ilha Mutum. Foram analisados 49 conteúdos estomacais de P. falkneri e 16 de P. motoro, obtidos de espécimes capturados através de pesca com anzol, fisga (arpão e espinhel. Os conteúdos estomacais foram analisados de acordo com os métodos de freqüência volumétrica e de ocorrência. A similaridade da dieta foi quantificada pelo índicede sobreposição de Pianka. As espécies revelaram flexibilidade alimentar, com ambas consumindo predominantemente moluscos na cheia, enquanto na seca a dieta de P. falkneri foi composta principalmente por peixes e a de P. motoro por insetos aquáticos. Os valores doíndice de sobreposição de nicho variaram entre 0,38 na seca (moderado e 0,94 na cheia (acentuado. A variação da composição das dietas foi atribuída às oscilações na disponibilidade dos recursos alimentares no ambiente.Feeding habits and trophic overlap of freshwater stingrays Potamotrygon falkneri e Potamotrygon motoro were evaluated in the upper Paraná river floodplain. Samples were collected during periods of drought (August/2004 and flood (January/2005 near Mutum island. Fishhook, harpoon and long line were used to capture the individuals and a total of 49 stomach contents of P. falkneri and 16 of P. motorowere analyzed. Diet composition was analyzed by the relative occurrence and volumetric frequencies. The trophic overlap was quantified by the index of niche overlap of Pianka. Results indicated that both species predominantly consumed mollusks during the floodseason, while in the drought season the diet of P. falkneri was composed mainly by fish and P. motoro for aquatic insects. The values of the index of niche overlap varied from 0.38, in

CRED Cumulative Map of Percent Scleractinian Coral Cover at Stingray Shoals

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

Dynamic Shape Capture of Free-Swimming Aquatic Life using Multi-view Stereo

Science.gov (United States)

Daily, David

2017-11-01

The reconstruction and tracking of swimming fish in the past has either been restricted to flumes, small volumes, or sparse point tracking in large tanks. The purpose of this research is to use an array of cameras to automatically track 50-100 points on the surface of a fish using the multi-view stereo computer vision technique. The method is non-invasive thus allowing the fish to swim freely in a large volume and to perform more advanced maneuvers such as rolling, darting, stopping, and reversing which have not been studied. The techniques for obtaining and processing the 3D kinematics and maneuvers of tuna, sharks, stingrays, and other species will be presented and compared. The National Aquarium and the Naval Undersea Warfare Center and.

Health issues for surfers.

Science.gov (United States)

Zoltan, Todd B; Taylor, Kenneth S; Achar, Suraj A

2005-06-15

Surfers are prone to acute injuries as well as conditions resulting from chronic environmental exposure. Sprains, lacerations, strains, and fractures are the most common types of trauma. Injury from the rider's own surfboard may be the prevailing mechanism. Minor wound infections can be treated on an outpatient basis with ciprofloxacin or trimethoprim-sulfamethoxazole. Jellyfish stings are common and may be treated with heat application. Other treatment regimens have had mixed results. Seabather's eruption is a pruritic skin reaction caused by exposure to nematocyst-containing coelenterate larvae. Additional surfing hazards include stingrays, coral reefs, and, occasionally, sharks. Otologic sequelae of surfing include auditory exostoses, tympanic membrane rupture, and otitis externa. Sun exposure and skin cancer risk are inherent dangers of this sport.

Debate: When it Comes to Modern Slavery, do Definitions Matter?

Directory of Open Access Journals (Sweden)

Fiona David

2015-09-01

Full Text Available On the 3rd of April 2015, Indonesian government officials visited the remote island village of Benjina.[1] This followed press reports by Associated Press (AP that Burmese men were being kept on Benjina island in cages, beaten with stingray tails and paid little or nothing, to fish for a company that occupies the port on the island, Pusaka Benjina Resources. [1] R McDowell and M Mason, ‘AP Investigation Prompts Emergency Rescue of 300 Plus Slaves’, AP,  3 April 2015, retrieved 23 July 2015, http://bigstory.ap.org/article/197048ef871f4b56b4a129d0e3c0f129/fishermen-rush-be-rescued-amid-indonesian-slavery-probe

Water-cooled spacecraft : DART to be launched by Russian Volna (Stingray) rocket

NARCIS (Netherlands)

Van Baten, T.; Buursink, J.; Hartmann, L.

2002-01-01

A25 September 2005, Barents Sea, near Murmansk.Ten metres under the surface of the sea, the launch tube of the Mstislav, a Rostropovich class nuclear submarine, grinds open. The countdown for the launch of a Volna R-29R slbm (Submarine-Launched Ballistic Missile) starts: For many years, satellites

CRED Towed-Diver Benthic Characterization Surveys at Stingray Shoals, Marianas Archipelago in 2003

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — To support NOAA Coral Reef Conservation Program (CRCP) long-term goals for sustainable management and conservation of coral reef ecosystems, towed-diver surveys...

Comparative anatomy of the extraocular muscles in four Myliobatoidei rays (Batoidea, Myliobatiformes).

Science.gov (United States)

Cunha, Carlo M; Oliveira, Luciano E; Kfoury, José R

2016-05-01

Extraocular muscles are classically grouped as four rectus and two oblique muscles. However, their description and potential associations with species behavior are limited. The objective was to characterize extraocular muscles in four Myliobatoidei rays from diverse habitats with divergent behaviors. Heads (10 per species) of Dasyatis hypostigma, Gymnura altavela, Mobula thurstoni and Pteroplatytrygon violacea were decalcified and dissected to characterize and describe extraocular muscles. Principal component analysis (PCA) was used to evaluate relationships between muscle length and species; for P. violacea, D. hypostigma and G. altavela, these were qualitatively and quantitatively consistent with the general pattern of extraocular muscles in vertebrates. In contrast, for M. thurstoni, the two oblique muscles were completely fused and there was a seventh extraocular muscle, named m. lateral rectus β (both were apparently novel findings in this species). There were also significant differences in eye disposition in the chondrocranium. The PCA axis 1 (rectus muscles) and PCA axis 2 (oblique muscles) accounted for 98.47% of data variability. Extraocular muscles had significant differences in length and important anatomical differences among sampled species that facilitated grouping species according to their life history. In conclusion, extraocular muscles are not uniform in all vertebrate species, thereby providing another basis for comparative studies. © 2016 Anatomical Society.

Hábitos alimentares e sobreposição trófica das raias Potamotrygon falkneri e Potamotrygon motoro (Chondrichthyes, Potamotrygonidae na planície alagável do alto rio Paraná, Brasil - DOI: 10.4025/actascibiolsci.v28i3.208 Feeding habitats and trophic overlap of the freshwater stingrays Potamotrygon falkneri e Potamotrygon motoro (Chondrichthyes, Potamotrygonidae in the upper Paraná river floodplain, Brazil - DOI: 10.4025/actascibiolsci.v28i3.208

Directory of Open Access Journals (Sweden)

Edson Fontes de Oliveira

2007-11-01

Full Text Available As raias Potamotrygon falkneri e Potamotrygon motoro foram avaliadas em relação à composição de suas dietas e a sobreposição do nicho trófico nos períodos de seca (agosto/2004 e cheia (janeiro/2005 na planície alagável do alto rio Paraná, em três estações de coleta próximas à ilha Mutum. Foram analisados 49 conteúdos estomacais de P. falkneri e 16 de P. motoro, obtidos de espécimes capturados através de pesca com anzol, fisga (arpão e espinhel. Os conteúdos estomacais foram analisados de acordo com os métodos de freqüência volumétrica e de ocorrência. A similaridade da dieta foi quantificada pelo índice de sobreposição de Pianka. As espécies revelaram flexibilidade alimentar, com ambas consumindo predominantemente moluscos na cheia, enquanto na seca a dieta de P. falkneri foi composta principalmente por peixes e a de P. motoro por insetos aquáticos. Os valores do índice de sobreposição de nicho variaram entre 0,38 na seca (moderado e 0,94 na cheia (acentuado. A variação da composição das dietas foi atribuída à s oscilações na disponibilidade dos recursos alimentares no ambiente.Feeding habits and trophic overlap of freshwater stingrays Potamotrygon falkneri e Potamotrygon motoro were evaluated in the upper Paraná river floodplain. Samples were collected during periods of drought (August/2004 and flood (January/2005 near Mutum island. Fishhook, harpoon and long line were used to capture the individuals and a total of 49 stomach contents of P. falkneri and 16 of P. motoro were analyzed. Diet composition was analyzed by the relative occurrence and volumetric frequencies. The trophic overlap was quantified by the index of niche overlap of Pianka. Results indicated that both species predominantly consumed mollusks during the flood season, while in the drought season the diet of P. falkneri was composed mainly by fish and P. motoro for aquatic insects. The values of the index of niche overlap varied from 0

Improved age control on early Homo fossils from the upper Burgi Member at Koobi Fora, Kenya

DEFF Research Database (Denmark)

Nielsen, Trine Kellberg

2013-01-01

Turkana Basin (Kenya). We identify the base of the Olduvai subchron (bC2n) plus a short isolated interval of consistently normal polarity that we interpret to be the Pre-Olduvai event. Combined with precession-forced (∼20 kyr [thousands of years]) wet–dry climate cycles resolved by Sr isotope ratios......, the magnetostratigraphic data allow us to construct an age model for the UBU deposits. We provide detailed age constraints for 15 hominin fossils from Area 131, showing that key specimens such as cranium KNM-ER 1470, partial face KNM-ER 62000 and mandibles KNM-ER 1482, KNM-ER 1801, and KNM-ER 1802 can be constrained...... the wet–dry climate cycles, supporting the hypothesis that the lacustrine Turkana Basin was a refugium during regionally dry periods. By establishing the observed first appearance datum of a marine-derived stingray in UBU deposits at 2.058 ± 0.034 Ma, we show that at this time the Turkana Basin...

Wake topology of under-actuated rajiform batoid robots

Science.gov (United States)

Valdivia Y Alvarado, Pablo; Weymouth, Gabriel; Thekoodan, Dilip; Patrikalakis, Nicholas

2011-11-01

Under-actuated continuous soft robots are designed to have modes of vibration that match desired body motions using minimal actuation. The desired modes of vibration are enabled by flexible continuous bodies with heterogenous material distributions. Errors or intentional approximations in the manufactured material distributions alter the achieved body motions and influence the resulting locomotion performance. An under-actuated continuous soft robot designed to mimic rajiform batoids such as stingrays is used to investigate the influence that fin kinematics variations have on wake topology, and the trade-offs that simplifying the body material structure has on achievable swimming performance. Pectoral fin kinematics in rajiform batoids are defined by traveling waves along the fin cord with particular amplitude envelopes along both the fin cord and span. Digital particle image velocimetry (DPIV) analysis of a prototype's wake structure and immersed-boundary numerical simulations are used to clarify the role of traveling wave wavelength, fin flapping frequency, and amplitude envelope characteristics on the resulting wake topology and swimming performance.

Orders out of chaos--molecular phylogenetics reveals the complexity of shark and stingray tapeworm relationships.

Science.gov (United States)

Caira, Janine N; Jensen, Kirsten; Waeschenbach, Andrea; Olson, Peter D; Littlewood, D Timothy J

2014-01-01

Novel molecular data are presented to resolve the long-standing issue of the non-monophyly of the elasmobranch-hosted tapeworm order Tetraphyllidea relative to the other acetabulate eucestode orders. Bayesian inference analyses of various combinations of full ssrDNA, and full or partial lsrDNA (D1-D3), sequence data, which included 134 species representing 97 genera across the 15 eucestode orders, were conducted. New ssrDNA data were generated for 82 species, partial lsrDNA data for 53 species, and full lsrDNA data for 29 species. The monophyly of each of the elasmobranch-hosted orders Cathetocephalidea, Litobothriidea, Lecanicephalidea and Rhinebothriidea was confirmed, as was the non-monophyly of the Tetraphyllidea. Two relatively stable groups of tetraphyllidean taxa emerged and are hereby designated as new orders. The Onchoproteocephalidea n. ord. is established to recognise the integrated nature of one undescribed and 10 described genera of hook-bearing tetraphyllideans, previously placed in the family Onchobothriidae, with the members of the order Proteocephalidea. The Phyllobothriidea n. ord. is established for a subset of 12 non-hooked genera characterised by scoleces bearing four bothridia each with an anterior accessory sucker; most parasitise sharks and have been assigned to the Phyllobothriidae at one time or another. Tentative ordinal placements are suggested for eight additional genera; placements for the remaining tetraphyllidean genera have not yet emerged. We propose that these 17 genera remain in the "Tetraphyllidea". Among these, particularly labile across analyses were Anthobothrium, Megalonchos, Carpobothrium, Calliobothrium and Caulobothrium. The unique association of Chimaerocestus with holocephalans, rather than with elasmobranchs, appears to represent a host-switching event. Both of the non-elasmobranch hosted clades of acetabulate cestodes (i.e. Proteocephalidea and Cyclophyllidea and their kin) appear to have had their origins with elasmobranch cestodes. Across analyses, the sister group to the clade of "terrestrial" cestode orders was found to be an elasmobranch-hosted genus, as was the sister to the freshwater fish- and tetrapod-hosted Proteocephalidea. Whilst further data are required to resolve outstanding nomenclatural and phylogenetic issues, the present analyses contribute significantly to an understanding of the evolutionary radiation of the entire Cestoda. Clearly, elasmobranch tapeworms comprise the backbone of cestode phylogeny. Copyright © 2013 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Novel Compounds From Shark and Stingray Epidermal Mucus With Antimicrobial Activity Against Wound Infection Pathogens

Science.gov (United States)

2014-03-01

consistency compared to mucus from any of the ray species. While this difference is difficult to describe, the terms “ gelatinous ” or “sticky” are...visualized using silver stain (Figure 3). As observed with the ray species, protein patterns for clearnose skates are consistent among individuals of the...three clearnose skates, Raja eglanteria, visualized with silver stain. Molecular weights of standard proteins are in kilodaltons (kD). 9

Novel Compounds from Shark and Stingray Epidermal Mucus With Antimicrobial Activity Against Wound Infection Pathogens

Science.gov (United States)

2013-03-01

Extraction with Enzymes Collaborators at Daemen College also tested papain and pepsin for their abilities to liberate proteins from the mucus...pellet. Papain is a cysteine protease and a common active ingredient in meat tenderizers. It is often used to dissociate cells in the first step of cell...various treatments with Papain and Pepsin. Lane 1: EDTA-DTT extract; Lane 2-4: Mucus pellet + Papain for 30, 40, and 60 min; Lane 5: Mucus pellet

Surgical hazards posed by marine and freshwater animals in Florida.

Science.gov (United States)

Howard, R J; Burgess, G H

1993-11-01

Marine and freshwater animals can cause injury to humans by biting, stinging, being poisonous to eat, and causing infections. Biting aquatic animals in Florida include sharks, barracudas, alligators, and moray eels. Devitalized tissue should be débrided, and vascular, neurologic, and tendinous injuries should be repaired. Radiographs should be obtained to examine the injury sit for fractures and retained foreign bodies (teeth). The spines of stingrays and marine catfish can cause soft tissue injury and infection. The spine has a recurved, serrated shape that may cause further injury and break if it is pulled out. The venom may cause local tissue necrosis requiring débridement. Soft tissue infections with marine Vibrio bacteria can occur after eating raw oysters or receiving even minor injuries from marine animals. Thirty-one individuals developed soft tissue infections, 49 developed sepsis, and 23 developed both sepsis and soft tissue infection with marine Vibrio species during a 12-year period. Sixteen patients developed necrotizing soft tissue infections. Treatment is with antibiotics and débridement when necrosis occurs.

Auditory evoked potential measurements in elasmobranchs

Science.gov (United States)

Casper, Brandon; Mann, David

2005-04-01

Auditory evoked potentials (AEP) were first used to examine hearing in elasmobranchs by Corwin and Bullock in the late 1970s and early 1980s, marking the first time AEPs had been measured in fishes. Results of these experiments identified the regions of the ear and brain in which sound is processed, though no actual hearing thresholds were measured. Those initial experiments provided the ground work for future AEP experiments to measure fish hearing abilities in a manner that is much faster and more convenient than classical conditioning. Data will be presented on recent experiments in which AEPs were used to measure the hearing thresholds of two species of elasmobranchs: the nurse shark, Ginglymostoma cirratum, and the yellow stingray, Urobatis jamaicencis. Audiograms were analyzed and compared to previously published audiograms obtained using classical conditioning with results indicating that hearing thresholds were similar for the two methods. These data suggest that AEP testing is a viable option when measuring hearing in elasmobranchs and can increase the speed in which future hearing measurements can be obtained.

Isopods (Isopoda: Aegidae, Cymothoidae, Gnathiidae associated with Venezuelan marine fishes (Elasmobranchii, Actinopterygii

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Lucy Bunkley-Williams

2006-12-01

Full Text Available The parasitic isopod fauna of fishes in the southern Caribbean is poorly known. In examinations of 12 639 specimens of 187 species of Venezuelan fishes, the authors found 10 species in three families of isopods (Gnathiids, Gnathia spp. from Diplectrum radiale *, Heteropriacanthus cruentatus *, Orthopristis ruber * and Trachinotus carolinus *; two aegids, Rocinela signata from Dasyatis guttata *, H. cruentatus *, Haemulon aurolineatum *, H. steindachneri * and O. ruber ; and Rocinela sp. from Epinephelus flavolimbatus *; five cymothoids: Anilocra haemuli from Haemulon boschmae *, H. flavolineatum * and H. steindachneri *; Anilocra cf haemuli from Heteropriacanthus cruentatus *; Haemulon bonariense*, O. ruber*, Cymothoa excisa in H. cruentatus *; Cymothoa oestrum in Chloroscombrus chrysurus, H. cruentatus* and Priacanthus arenatus ; Cymothoa sp. in O. ruber; Livoneca sp. from H. cruentatus *; and Nerocila fluviatilis from H. cruentatus * and P. arenatus *. The Rocinela sp. and A. cf haemuli in the southern Caribbean could represent new species. The abundance of A. cf haemuli appears to have drastically reduced from 1994 to 1999 in the Gulf of Cariaco. The Cymothoa sp. represents an undescribed species that is apparently host specific to O. ruber . It does not occur in the Gulf of Cariaco, but is relatively abundant on the Caribbean coast of Sucre State, Venezuela. The Livoneca sp. is an undescribed species host specific to Diapterus rhombeus, Cymothoa excisa and C. oestrum were thought to have distinct host preferences, but both infected the Heteropriacanthus cruentatus in the present study.Gnathia spp. are reported from Venezuelan waters for the first time. Twenty new host records* are noted. The fish-associated isopod fauna is much more extensive and important than has previously been suspected. Rev. Biol. Trop. 54 (Suppl. 3: 175-188. Epub 2007 Jan. 15.Se conoce muy poco acerca de la fauna de isópodos parásitos de peces en el Caribe Sur. Tras

Hypothesis and Theory: Revisiting Views on the Co-evolution of the Melanocortin Receptors and the Accessory Proteins, MRAP1 and MRAP2.

Science.gov (United States)

Dores, Robert M

2016-01-01

The evolution of the melanocortin receptors (MCRs) is closely associated with the evolution of the melanocortin-2 receptor accessory proteins (MRAPs). Recent annotation of the elephant shark genome project revealed the sequence of a putative MRAP1 ortholog. The presence of this sequence in the genome of a cartilaginous fish raises the possibility that the mrap1 and mrap2 genes in the genomes of gnathostome vertebrates were the result of the chordate 2R genome duplication event. The presence of a putative MRAP1 ortholog in a cartilaginous fish genome is perplexing. Recent studies on melanocortin-2 receptor (MC2R) in the genomes of the elephant shark and the Japanese stingray indicate that these MC2R orthologs can be functionally expressed in CHO cells without co-expression of an exogenous mrap1 cDNA. The novel ligand selectivity of these cartilaginous fish MC2R orthologs is discussed. Finally, the origin of the mc2r and mc5r genes is reevaluated. The distinctive primary sequence conservation of MC2R and MC5R is discussed in light of the physiological roles of these two MCR paralogs.

Place learning prior to and after telencephalon ablation in bamboo and coral cat sharks (Chiloscyllium griseum and Atelomycterus marmoratus).

Science.gov (United States)

Fuss, Theodora; Bleckmann, Horst; Schluessel, Vera

2014-01-01

This study assessed complex spatial learning and memory in two species of shark, the grey bamboo shark (Chiloscyllium griseum) and the coral cat shark (Atelomycterus marmoratus). It was hypothesized that sharks can learn and apply an allocentric orientation strategy. Eight out of ten sharks successfully completed the initial training phase (by locating a fixed goal position in a diamond maze from two possible start points) within 14.9 ± 7.6 sessions and proceeded to seven sets of transfer tests, in which sharks had to perform under altered environmental conditions. Transfer tests revealed that sharks had oriented and solved the tasks visually, using all of the provided environmental cues. Unintentional cueing did not occur. Results correspond to earlier studies on spatial memory and cognitive mapping in other vertebrates. Future experiments should investigate whether sharks possess a cognitive spatial mapping system as has already been found in several teleosts and stingrays. Following the completion of transfer tests, sharks were subjected to ablation of most of the pallium, which compromised their previously acquired place learning abilities. These results indicate that the telencephalon plays a crucial role in the processing of information on place learning and allocentric orientation strategies.

Three new species of Echinobothrium (Cestoda: Diphyllidea) from Indo-Pacific stingrays of the genus Pastinachus (Rajiformes: Dasyatidae)

Czech Academy of Sciences Publication Activity Database

Kuchta, Roman; Caira, J. N.

2010-01-01

Roč. 57, č. 3 (2010), s. 185-196 ISSN 0015-5683 R&D Projects: GA AV ČR KJB600960902; GA ČR GAP506/10/1994; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : Borneo * Echinobothrium nataliae * Echinobothrium reginae * Echinobothrium vojtai * hook formula * Madagascar * Macrobothridium Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.533, year: 2010

A new species of Acanthobothrium (Eucestoda: Onchobothriidae in Aetobatus cf. narinari (Myliobatidae from Campeche, México

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Erick Rodríguez-Ibarra

2018-03-01

Full Text Available Abstract The helminthological examination of nine individuals of Aetobatus cf. narinari (spotted eagle ray; raya pinta; arraia pintada revealed the presence of an undescribed species of cestode of the genus Acanthobothrium. The stingrays were collected from four locations in México: Laguna Términos, south of Isla del Carmen and the marine waters north of Isla del Carmen and Champotón, in the State of Campeche, and Isla Holbox, State of Quintana Roo. The new species, nominated Acanthobothrium marquesi, is a category 3 species (i.e, the strobila is long, has more than 50 proglottids, the numerous testicles greater than 80, and has asymmetrically-lobed ovaries; at the present, the only category 3 species that has been reported in the Western Atlantic Ocean is Acanthobothrium tortum. Acanthobothrium marquesi n. sp. can be distinguished from A. tortum by length (26.1 cm vs. 10.6 cm, greater number of proglottids (1,549 vs. 656, a larger scolex (707 µm long by 872 µm wide vs. 699 µm long by 665 µm wide, larger bothridia (626 µm long by 274 µm wide vs. 563 µm long by 238 µm wide. This is the first report of a species of Acanthobothrium from the Mexican coast of the Gulf México.

Elasmobranch bycatch in the Italian Adriatic pelagic trawl fishery

Science.gov (United States)

Fortuna, Caterina Maria; Moro, Fabrizio; Sala, Antonello

2018-01-01

Elasmobranchs are among the most threatened long-lived marine species worldwide, and incidental capture is a major source of mortality. The northern central Adriatic Sea, though one of the most overfished basins of the Mediterranean Sea, supports a very valuable marine biodiversity, including elasmobranchs. This study assesses the impact of the northern central Adriatic pelagic trawl fishery on common smooth-hound (Mustelus mustelus), spiny dogfish (Squalus acanthias), common eagle ray (Myliobatis aquila), and pelagic stingray (Pteroplatytrygon violacea) by examining incidental catches recorded between 2006 and 2015. The distribution of bycatch events was evaluated using geo-referenced data. Generalized Linear Models were computed to standardize the catch of the four species and to predict the relative abundance of bycatch events. Data analysis shows that most bycatch events involving all four species occurred in the northern Adriatic Sea. The models predicted significant, distinct temporal patterns of standardized catches in line with previous investigations. Water depth, season, and fishing region were the best predictors to explain bycatch events. The present data suggest that the northern Adriatic may be an important nursery area for several elasmobranchs. They also highlight the urgent need for a better understanding of the interactions between elasmobranchs and fisheries to develop and apply suitable, ad hoc management measures. PMID:29377920

A new species of Acanthobothrium (Eucestoda: Onchobothriidae) in Aetobatus cf. narinari (Myliobatidae) from Campeche, México.

Science.gov (United States)

Rodríguez-Ibarra, Erick; Pulido-Flores, Griselda; Violante-González, Juan; Monks, Scott

2018-01-01

The helminthological examination of nine individuals of Aetobatus cf. narinari (spotted eagle ray; raya pinta; arraia pintada) revealed the presence of an undescribed species of cestode of the genus Acanthobothrium. The stingrays were collected from four locations in México: Laguna Términos, south of Isla del Carmen and the marine waters north of Isla del Carmen and Champotón, in the State of Campeche, and Isla Holbox, State of Quintana Roo. The new species, nominated Acanthobothrium marquesi, is a category 3 species (i.e, the strobila is long, has more than 50 proglottids, the numerous testicles greater than 80, and has asymmetrically-lobed ovaries); at the present, the only category 3 species that has been reported in the Western Atlantic Ocean is Acanthobothrium tortum. Acanthobothrium marquesi n. sp. can be distinguished from A. tortum by length (26.1 cm vs. 10.6 cm), greater number of proglottids (1,549 vs. 656), a larger scolex (707 µm long by 872 µm wide vs. 699 µm long by 665 µm wide), larger bothridia (626 µm long by 274 µm wide vs. 563 µm long by 238 µm wide). This is the first report of a species of Acanthobothrium from the Mexican coast of the Gulf México.

Elasmobranch bycatch in the Italian Adriatic pelagic trawl fishery.

Directory of Open Access Journals (Sweden)

Sara Bonanomi

Full Text Available Elasmobranchs are among the most threatened long-lived marine species worldwide, and incidental capture is a major source of mortality. The northern central Adriatic Sea, though one of the most overfished basins of the Mediterranean Sea, supports a very valuable marine biodiversity, including elasmobranchs. This study assesses the impact of the northern central Adriatic pelagic trawl fishery on common smooth-hound (Mustelus mustelus, spiny dogfish (Squalus acanthias, common eagle ray (Myliobatis aquila, and pelagic stingray (Pteroplatytrygon violacea by examining incidental catches recorded between 2006 and 2015. The distribution of bycatch events was evaluated using geo-referenced data. Generalized Linear Models were computed to standardize the catch of the four species and to predict the relative abundance of bycatch events. Data analysis shows that most bycatch events involving all four species occurred in the northern Adriatic Sea. The models predicted significant, distinct temporal patterns of standardized catches in line with previous investigations. Water depth, season, and fishing region were the best predictors to explain bycatch events. The present data suggest that the northern Adriatic may be an important nursery area for several elasmobranchs. They also highlight the urgent need for a better understanding of the interactions between elasmobranchs and fisheries to develop and apply suitable, ad hoc management measures.

A test of the utility of DNA barcoding in the radiation of the freshwater stingray genus Potamotrygon (Potamotrygonidae, Myliobatiformes

Directory of Open Access Journals (Sweden)

Daniel Toffoli

2008-01-01

Full Text Available DNA barcoding is a recently proposed global standard in taxonomy based on DNA sequences. The two main goals of DNA barcoding methodology are assignment of specimens to a species and discovery of new species. There are two main underlying assumptions: i reciprocal monophyly of species, and ii intraspecific divergence is always less than interspecific divergence. Here we present a phylogenetic analysis of the family Potamotrygonidae based on mitochondrial cytochrome c oxidase I gene, sampling 10 out of the 18 to 20 valid species including two non-described species. Potamotrygonidae systematics is still not fully resolved with several still-to-be-described species while some other species are difficult to delimit due to overlap in morphological characters and because of sharing a complex color patterns. Our results suggest that the family passed through a process of rapid speciation and that the species Potamotrygon motoro, P. scobina, and P. orbignyi share haplotypes extensively. Our results suggest that systems of identification of specimens based on DNA sequences, together with morphological and/or ecological characters, can aid taxonomic studies, but delimitation of new species based on threshold values of genetic distances are overly simplistic and misleading.

Direct Drive Wave Energy Buoy

Energy Technology Data Exchange (ETDEWEB)

Rhinefrank, Kenneth [Columbia Power Technologies, Inc., Charlottesville, VA (United States); Lamb, Bradford [Columbia Power Technologies, Inc., Charlottesville, VA (United States); Prudell, Joseph [Columbia Power Technologies, Inc., Charlottesville, VA (United States); Hammagren, Erik [Columbia Power Technologies, Inc., Charlottesville, VA (United States); Lenee-Bluhm, Pukha [Columbia Power Technologies, Inc., Charlottesville, VA (United States)

2016-08-22

This Project aims to satisfy objectives of the DOE’s Water Power Program by completing a system detailed design (SDD) and other important activities in the first phase of a utility-scale grid-connected ocean wave energy demonstration. In early 2012, Columbia Power (CPwr) had determined that further cost and performance optimization was necessary in order to commercialize its StingRAY wave energy converter (WEC). CPwr’s progress toward commercialization, and the requisite technology development path, were focused on transitioning toward a commercial-scale demonstration. This path required significant investment to be successful, and the justification for this investment required improved annual energy production (AEP) and lower capital costs. Engineering solutions were developed to address these technical and cost challenges, incorporated into a proposal to the US Department of Energy (DOE), and then adapted to form the technical content and statement of project objectives of the resulting Project (DE-EE0005930). Through Project cost-sharing and technical collaboration between DOE and CPwr, and technical collaboration with Oregon State University (OSU), National Renewable Energy Lab (NREL) and other Project partners, we have demonstrated experimentally that these conceptual improvements have merit and made significant progress towards a certified WEC system design at a selected and contracted deployment site at the Wave Energy Test Site (WETS) at the Marine Corps Base in Oahu, HI (MCBH).

Selenium and Mercury Interactions in Apex Predators from the Gulf of Trieste (Northern Adriatic Sea

Directory of Open Access Journals (Sweden)

Jadran Faganeli

2018-02-01

Full Text Available Since the environmental levels of selenium (Se can moderate the bioaccumulation and toxicity of mercury (Hg in marine organisms, their interactions were studied in seawater, sediments, plankton and the benthic (Bull ray Pteromylaeus bovinus, Eagle ray Myliobatis aquila and the pelagic (Pelagic stingray Dasyiatis violacea rays, as apex predators in the Gulf of Trieste (Northern Adriatic Sea. Male and female rays showed no difference in the Se contents in muscle tissue. Pelagic species contained higher Se levels in muscle but slightly lower levels in the livers of both genders. The Hg/Se ratios in seawater dissolved and colloidal fractions, plankton and sediment were <0.5, while those in particulate matter were <1.3. In benthic ray species, a parallel increase in Se and Hg in muscle was observed, so that an increased in Hg (MeHg bioaccumulation results in Se coaccumulation. The Hg/Se ratios (molar in muscle and liver of pelagic and benthic rays were <1.4 and <0.7, respectively. The low levels of Hg in muscle and liver in all the ray species corresponded to low Hg/Se ratios and increases in muscle and liver to 1 at 7 µg/g, dry weight (dw and 5 µg/g dw, respectively, i.e., about 1.6 µg/g wet weight (ww.

Who's My Daddy? Considerations for the influence of sexual selection on multiple paternity in elasmobranch mating systems.

Science.gov (United States)

Lyons, Kady; Chabot, Chris L; Mull, Christopher G; Paterson Holder, Corinne N; Lowe, Christopher G

2017-08-01

Polyandry resulting in multiply-sired litters has been documented in the majority of elasmobranch species examined to date. Although commonly observed, reasons for this mating system remain relatively obscure, especially in batoids. The round stingray ( Urobatis halleri ) is an abundant, well-studied elasmobranch distributed throughout the northeastern Pacific that we used to explore hypotheses regarding multiple paternity in elasmobranchs. Twenty mid- to late-term pregnant females were sampled off the coast of southern California and their litters analyzed for the occurrence of multiple paternity using five nuclear microsatellite loci. In addition, embryo sizes and their position within the female reproductive system (i.e., right or left uterus) were recorded and used to make inferences for patterns of ovulation. Multiple paternity was observed in 90% of litters and male reproductive success within litters was relatively even among sires. High variability in testes mass was observed suggesting that sperm competition is high in this species, although male reproductive success per litter appeared to be relatively even. Using embryo size as a proxy for fertilization, females were found to exhibit a variety of ovulation patterns that could function to limit a male's access to eggs and possibly promote high rates of multiple paternity. Our study highlights that elasmobranch mating systems may be more varied and complex than presumed and further investigation is warranted.

Calcified cartilage or bone? Collagens in the tessellated endoskeletons of cartilaginous fish (sharks and rays).

Science.gov (United States)

Seidel, Ronald; Blumer, Michael; Pechriggl, Elisabeth-Judith; Lyons, Kady; Hall, Brian K; Fratzl, Peter; Weaver, James C; Dean, Mason N

2017-10-01

The primary skeletal tissue in elasmobranchs -sharks, rays and relatives- is cartilage, forming both embryonic and adult endoskeletons. Only the skeletal surface calcifies, exhibiting mineralized tiles (tesserae) sandwiched between a cartilage core and overlying fibrous perichondrium. These two tissues are based on different collagens (Coll II and I, respectively), fueling a long-standing debate as to whether tesserae are more like calcified cartilage or bone (Coll 1-based) in their matrix composition. We demonstrate that stingray (Urobatis halleri) tesserae are bipartite, having an upper Coll I-based 'cap' that merges into a lower Coll II-based 'body' zone, although tesserae are surrounded by cartilage. We identify a 'supratesseral' unmineralized cartilage layer, between tesserae and perichondrium, distinguished from the cartilage core in containing Coll I and X (a common marker for mammalian mineralization), in addition to Coll II. Chondrocytes within tesserae appear intact and sit in lacunae filled with Coll II-based matrix, suggesting tesserae originate in cartilage, despite comprising a diversity of collagens. Intertesseral joints are also complex in their collagenous composition, being similar to supratesseral cartilage closer to the perichondrium, but containing unidentified fibrils nearer the cartilage core. Our results indicate a unique potential for tessellated cartilage in skeletal biology research, since it lacks features believed diagnostic for vertebrate cartilage mineralization (e.g. hypertrophic and apoptotic chondrocytes), while offering morphologies amenable for investigating the regulation of complex mineralized ultrastructure and tissues patterned on multiple collagens. Copyright © 2017 Elsevier Inc. All rights reserved.

Previous 60-Co radiation from Paratrygon aiereba mucus induces the production of highly responsive antibodies and a better immune response in mice

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Thomazi, Gabriela Ortega Coelho; Alves, Glaucie Jussilane; Turíbio, Thompson de Oliveira; Rocha, André Moreira; Aires, Raquel da Silva; Jácome, Larissa Barros Silvestre; Spencer, Patrick Jack, E-mail: gabiortegacoelho@usp.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil). Centro de Biotecnologia; Costa, Andrea da; Rodrigues, Jaqueline Pollizeli; Galisteo Júnior, Andrés Jimenez; Andrade Júnior, Heitor Franco de, E-mail: hfandrad@usp.br, E-mail: raquelaires@itpacporto.com.br [Universidade de São Paulo (USP), São Paulo, SP (Brazil). Laboratório de Protozoologia; Seibert, Carla Simone, E-mail: seibertcs@uft.edu.br [Universidade Federal do Tocantins (UFT), Porto Nacional, TO (Brazil)

2017-07-01

Wounds from stinging freshwater stingrays are painful, difficult to heal and cause extensive necrosis and systemic phenomena. The treatment is symptomatic, of low efficiency and there is no therapy, which causes more suffering to the injured. This study aimed to evaluate the immune response induced by the native or irradiated by 60-Co gamma from Paratrygon aiereba mucus. IPEN’s Committee on Ethics in the Use of Animals (n.º126/2013) and lanes captured under license from the Chico Mendes Institute for Biodiversity Conservation (n.º6781-1/2014) approved this research. For the assays, sera from Swiss mice previously immunized against native or irradiated mucus were used. The proliferation of splenic B cells in response to mucus was evaluated by the In Vitro Induced Antibody Production method and serum and splenic cytokines were also quantified. Our data demonstrate that the irradiated mucus of P. aiereba induces greater production of antibodies and more immunological memory in the mice. Spleen cells from animals immunized against irradiated mucus produced IFN-γ, TNF-α and IL-10, and serum TNF-α (immunized group against irradiated mucus) and IL-6 and IL-17 (immunized group against native mucus). The results corroborate the use of ionizing radiation, with production of highly responsive antibodies and better immune response, besides proving that Paratrygon aiereba mucus is capable of stimulating cellular and humoral adaptive immune response, contributing to the continuity of associated investigations. (author)

Previous 60-Co radiation from Paratrygon aiereba mucus induces the production of highly responsive antibodies and a better immune response in mice

International Nuclear Information System (INIS)

Thomazi, Gabriela Ortega Coelho; Alves, Glaucie Jussilane; Turíbio, Thompson de Oliveira; Rocha, André Moreira; Aires, Raquel da Silva; Jácome, Larissa Barros Silvestre; Spencer, Patrick Jack

2017-01-01

Wounds from stinging freshwater stingrays are painful, difficult to heal and cause extensive necrosis and systemic phenomena. The treatment is symptomatic, of low efficiency and there is no therapy, which causes more suffering to the injured. This study aimed to evaluate the immune response induced by the native or irradiated by 60-Co gamma from Paratrygon aiereba mucus. IPEN’s Committee on Ethics in the Use of Animals (n.º126/2013) and lanes captured under license from the Chico Mendes Institute for Biodiversity Conservation (n.º6781-1/2014) approved this research. For the assays, sera from Swiss mice previously immunized against native or irradiated mucus were used. The proliferation of splenic B cells in response to mucus was evaluated by the In Vitro Induced Antibody Production method and serum and splenic cytokines were also quantified. Our data demonstrate that the irradiated mucus of P. aiereba induces greater production of antibodies and more immunological memory in the mice. Spleen cells from animals immunized against irradiated mucus produced IFN-γ, TNF-α and IL-10, and serum TNF-α (immunized group against irradiated mucus) and IL-6 and IL-17 (immunized group against native mucus). The results corroborate the use of ionizing radiation, with production of highly responsive antibodies and better immune response, besides proving that Paratrygon aiereba mucus is capable of stimulating cellular and humoral adaptive immune response, contributing to the continuity of associated investigations. (author)

Morfometria de raias continentais (Chondrichthyes, Potamotrygonidae do alto rio Paraná, Brasil = Morphometry of upper Paraná river freshwater stingrays (Chondrichthyes, Potamotrygonidae

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Antonio Guilherme Cândido da Silva

2007-10-01

Full Text Available Potamotrygonidae constitui o único grupo recente de Chondrichthyes cujo habitat está restrito, exclusivamente, a águas continentais. Na planície de inundação do Alto rio Paraná, espécies desta família estabeleceram-se após o fechamento das comportas da usina hidrelétrica de Itaipu, a jusante. O objetivo deste trabalho foi, utilizando medidas corporais, identificar diferenças morfométricas entre indivíduos de Potamotrygon cf. motoro (Natterer in Müller & Henle, 1841 e Potamotrygon falkneri Castex & Maciel, 1963 capturadosnesta região, bem como estimar o tamanho com que machos destas espécies atingem a maturidade gonadal. Machos de P. falkneri e P. cf. motoro das populações avaliadas atingem a maturidade gonadal com largura do disco variando em torno de 26 cm e 23 cm, respectivamente. Na comparação das espécies, P. cf. motoro apresentou maior distânciaproporcional entre as narinas e maior comprimento proporcional da cauda e dos espiráculos. Identificou-se dimorfismo sexual secundário para P. falkneri, consistindo da presença de fileiras laterais de espinhos na cauda das fêmeas. Estudos futuros de morfologiafuncional e ecomorfologia poderão esclarecer o significado das diferenças morfométricas para o modo de vida destas espécies.Potamotrygonidae is the only extant chondrichthyan group restricted exclusively to freshwater. This family invaded the UpperParaná river system after the closing of Itaipu Dam. This study aimed to identify morphometric differences between Potamotrygon cf. motoro (Natterer in Müller & Henle, 1841 and Potamotrygon falkneri Castex & Maciel, 1963 sampled in that area, and estimate male size at gonadal maturation. P. falkneri and P. cf. motoro males reach gonadal maturation at 26 cm and 23 cm disc width, respectively. Comparing both species, P. cf. motoro presented larger tail, spiracles and distance between nostrils. Lateral small stings on tails ofP. falkneri females were observed as secondary sexual dimorphism. Further studies on functional morphology and ecomorphology may point the meaning of morphometric differences to these species’ ecological interactions.

Marine envenomations in returning French travellers seen in a tropical diseases unit, 2008-13.

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Henn, Aurélia; Pérignon, Alice; Monsel, Gentiane; Larréché, Sébastien; Caumes, Eric

2016-02-01

Travel and aquatic activities are increasing in tropical regions. The risk and the spectrum of marine envenomation are unknown in travellers. This work aims to evaluate the prevalence and the characteristics of marine envenomations in returning travellers. We retrospectively studied the medical charts of all returning travellers presenting with a health problem in a French tropical disease unit between 2008 and 2013, with focus on travellers complaining of marine envenomation. Characteristics of each type of envenomation are described. Of the 3315 travellers seen during the study period, 43 consulted for a presumed marine envenomation. Six patients were excluded, leaving 37 cases of confirmed marine envenomation. It corresponds to a prevalence of 1.1%. Sex ratio was balanced with 18 men and 19 women. Median age was 42 years (range 25-68 years). Median travel duration was 14 days (range: 6-62 days). The main travel destination was Southeast Asia in 10 cases, followed by islands of East Africa in seven cases. Median elapsed time between envenomation and consultation was 14 days (range: 2-130 days). The purpose of travel was tourism in all cases. The main clinical aspects were oedema, sting marks, cellulitis and flagellations. Eleven cases were presumably caused by corals, 10 by stonefish, 8 by jellyfish, 2 by weever fish, 2 by starfish, 2 by stingray, 1 by lionfish and 1 by sea anemone. Prevalence of marine envenomation is low in returning travellers. They are mostly caused by corals, stonefish and jellyfish. © International Society of Travel Medicine, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Direct microCT imaging of non-mineralized connective tissues at high resolution.

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Naveh, Gili R S; Brumfeld, Vlad; Dean, Mason; Shahar, Ron; Weiner, Steve

2014-01-01

The 3D imaging of soft tissues in their native state is challenging, especially when high resolution is required. An X-ray-based microCT is, to date, the best choice for high resolution 3D imaging of soft tissues. However, since X-ray attenuation of soft tissues is very low, contrasting enhancement using different staining materials is needed. The staining procedure, which also usually involves tissue fixation, causes unwanted and to some extent unknown tissue alterations. Here, we demonstrate that a method that enables 3D imaging of soft tissues without fixing and staining using an X-ray-based bench-top microCT can be applied to a variety of different tissues. With the sample mounted in a custom-made loading device inside a humidity chamber, we obtained soft tissue contrast and generated 3D images of fresh, soft tissues with a resolution of 1 micron voxel size. We identified three critical conditions which make it possible to image soft tissues: humidified environment, mechanical stabilization of the sample and phase enhancement. We demonstrate the capability of the technique using different specimens: an intervertebral disc, the non-mineralized growth plate, stingray tessellated radials (calcified cartilage) and the collagenous network of the periodontal ligament. Since the scanned specimen is fresh an interesting advantage of this technique is the ability to scan a specimen under load and track the changes of the different structures. This method offers a unique opportunity for obtaining valuable insights into 3D structure-function relationships of soft tissues.

Tropical dermatology: marine and aquatic dermatology.

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Haddad, Vidal; Lupi, Omar; Lonza, Juan Pedro; Tyring, Stephen K

2009-11-01

Dermatoses caused by marine organisms are frequently seen in dermatology clinics worldwide. Cutaneous injuries after exposure to marine environments include bacterial and fungal infections and lesions caused by aquatic plants and protists. Some of these diseases are well known by dermatologists, such as Vibrio vulnificus septicemia and erysipeloid, but others are uncommon, such as envenomation caused by ingestion or contact with certain dinoflagellates or cyanobacteria, which are associated with rashes that can begin within minutes after exposure. Many marine/aquatic invertebrates, such as sponges, cnidarians, echinoderms, crustaceans, and mollusks, are associated with different kinds of dermatologic lesions that can vary from irritant or allergic contact dermatitis to physical trauma and envenomations. These cutaneous lesions may result in mild local reactions or can be associated with severe systemic reactions. Invertebrate animals, such as cnidarians, sea urchins, and worms, and aquatic vertebrates, such as venomous fishes and stingrays, are commonly associated with skin lesions in many countries, where they can constitute occupational dermatoses among fishermen and scuba divers, but they can also be observed among persons who contact these animals in kitchens or beaches. The presence of unusual lesions, a recent travel history, and/or a report of contact with an aquatic environment (including ownership of a marine or freshwater aquarium) should alert the dermatologist to the etiology of the cutaneous problems. After completing this learning activity, participants should be able to recognize the cutaneous manifestations of marine/aquatic infections, bites, stings, and wounds, etc., treat the cutaneous manifestations of marine/aquatic injuries, and help prevent marine/aquatic injuries.

A new species of Neotropical freshwater stingray of the genus Potamotrygon Garman, 1877 from the Río Madrede Díos, Peru (Chondrichthyes: Potamotrygonidae

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João Paulo C.B. da Silva

2011-01-01

Full Text Available Potamotrygon tatianae sp. nov., is described from Río Madre de Díos, Peru, upper Rio Madeira basin. The new species is distinguished from all congeners by a unique combination of characters, including its dorsal color pattern formed by a relatively slender, highly convoluted, beige to dark brown vermicular pattern, a single row of dorsal tail spines, and a relatively longer tail posterior to caudal stings. Potamotrygon tatianae sp. nov., occurs sympatrically with other species of Potamotrygon (P. falkneri, P. orbignyi and P. motoro. From the similar species P. falkneri, P. tatianae sp. nov., is further distinguished by the absence of circular, reniform, and oval spots, by its proportionally much longer tail, by having dorsal tail spines in one irregular row, and by features of the ventral lateral-line canal, dermal denticles and neurocranium. From P. orbignyi, the new species is distinct by lacking a reticulate pattern on dorsal disc and by the presence of two angular cartilages. From P. motoro, P. tatianae sp. nov., is further separated by the lack of ocelli formed by strong black concentric rings, by the more flattened aspect of its head and disc, and by having smaller and more numerous teeth. The discovery of a new species that so closely resembles a congeneric form in color pattern, a feature highly variable within the latter, highlights the importance of examining large series of individuals and of detailed morphological analyses in revealing the potentially highly cryptic nature of the diversity within the family.

A new species of Euzetia (Monogenea: Monocotylidae on the gills of Rhinoptera bonasus (Rhinopteridae from Ciudad del Carmen, Campeche, México Una especie nueva de Euzetia (Monogenea: Monocotylidae de las branquias de Rhinoptera bonasus (Rhinopteridae de Ciudad del Carmen, Campeche, México

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Griselda Pulido-Flores

2008-08-01

Full Text Available Euzetia lamothei n. sp. (Monogenea: Euzetiinae is described from the gills of the stingray, Rhinoptera bonasus, collected from marine waters near Ciudad del Carmen, Campeche, Mexico. The species is assigned to Euzetia Chisholm and Whittington, 2001 because it has a haptor with 10 peripheral loculi and 1 central loculus flanked by 2 lateral loculi. The species described herein can be distinguished from the only known member of the genus, E.occultum, by the morphology of the male copulatory organ, the vas deferens sigmoid, and the presence of a vaginal chamber. Euzetia lamothei n. sp. was found on 1 of 7 R.bonasus (14%. This species is the first record of a member of the genus from the neotropics, the first from Mexico, and the second report of a monocotylid from Rhinoptera.Se describe Euzetia lamothei n. sp. (Monogenea: Euzetiinae, parásito de la branquias de la mantarraya Rhinoptera bonasus, recolectada en Ciudad del Carmen, Campeche, México. Los ejemplares se asignaron a Euzetia Chisholm y Whittington, 2001 porque presentan un haptor con 10 loculi periféricos y 1 loculus central flanqueado por 2 loculi laterales. La especie aquí descrita se distingue de E.occultum por la morfología del órgano copulador, el vaso deferente sigmoide y la presencia de una cámara vaginal. Euzetia lamothei n. sp. se encontró en 1 de 7 R.bonasus (14%. Esta especie representa el primer registro de un miembro del género en el neotrópico, además es el primer registro en México, y el segundo de un monocotílido de Rhinoptera.

An investigation of the co-evolutionary relationships between onchobothriid tapeworms and their elasmobranch hosts.

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Caira, J N; Jensen, K

2001-07-01

There is general consensus that the living elasmobranchs comprise a monophyletic taxon. There is evidence that, among tetraphyllidean tapeworms, the approximately 201 hooked species (Onchobothriidae) may also comprise a monophyletic group. Determinations of host specificity are contingent upon correct specific identifications. Since 1960, over 200 new elasmobranch species and over 100 new onchobothriid species have been described. Some confidence can be placed in host and parasite identifications of recent studies, but specific identifications provided in older literature in many cases are suspect. There is some consensus among published works on the phylogenetic relationships among elasmobranchs. Phylogenetic relationships among onchobothriids remain largely unresolved. Elasmobranchs have been poorly sampled for onchobothriids; records exist for approximately 20% of the 911 species and approximately 44% of the 170 elasmobranch genera. Onchobothriids are remarkably host specific, exhibiting essentially oioxenous specificity for their definitive hosts. Multiple onchobothriid species commonly parasitise the same host species; in some cases these are congeners, in other cases these are members of two different onchobothriid genera. There is substantial incongruence between available host and parasite phylogenies. For example, Acanthobothrium is by far the most ubiquitous onchobothriid genus, parasitising almost all orders of elasmobranchs known to host onchobothriids, yet, there is no evidence of major clades of Acanthobothrium corresponding to postulated major subgroupings of elasmobranchs (e.g. Galea and Squalea or sharks and rays). Potamotrygonocestus appears to be among the most basal onchobothriid groups, yet it parasitises one of the most derived elasmobranch groups (the freshwater stingray genus Potamotrygon). It appears that congeners parasitising the same host species are not necessarily each other's closest relatives. At this point the preliminary and

PENGEMBANGAN MAKANAN FORMULA ANAK BALITA MENGGUNAKAN BERBAGAI JENIS IKAN LAUT DAN RUMPUT LAUT

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Uken Soetrisno

2012-11-01

Full Text Available ABSTRACT Background:  Deficiency in energy, protein and micronutrient of children under five years can cause growth faltering, besides the delayed in mental development and easily infected. Indonesia is highly potential in marine food sources, included fishes and seaweeds which are rich in macro and micronutrients. Formulated food made of fish were well accepted, but was not proven to improve growth significantly; while usage of seaweeds has not been explored. Objectives:  To produce formulated food, which contain macro and micronutrient that important for growth and mental development. The results will encourage usage of marine food sources and development of feasible food processing. Methods:  Food base included carbohydrate sources: rice flour, sweet corn, yellow yam, and sweet plaintain; protein sources: stingray, shark, tuna, greyfish and soybean. Sources of micronutrients were vegetables and seaweeds. Cooking oil and sugar were added to make 400 kCal energy content per 100 g formula and improve taste. Quality evaluation were tested: protein score, nutrient content, sensoric test and water absorbability of the formulated food.Results: Four kinds of formula were developed and well accepted by the panelist. Those formula have low water absorbtion and good sensoric quality. Protein scores are 84-97%, higher than that of soybean. Content of folate, vitamin A, iodine and Zn per 100 g formula can fulfill 70-110% daily allowance of children under five years old. Conclusions: Formulated food based on marine fishes and seaweeds were well accepted, with calculated protein scores were higher than soybean’s. Micronutrients content were high in all formula. There is a need to explore all potential benefits of the marine food sources, both protein sources and seaweeds, to develop other formulated foods for children. [Penel Gizi Makan 2007, 30(1: 1-7] Keywords:  food formula, marine fishes, seaweeds, sensoric quality, children under five years old.

KEBIJAKAN PENGELOLAAN HASIL TANGKAPAN SAMPINGAN TUNA LONGLINE DI SAMUDERA HINDIA

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Budi Nugraha

2013-11-01

Full Text Available Tuna longline atau rawai tuna merupakan salah satu alat tangkap yang sangat efektif untuk menangkap tuna. Selain efektif alat tangkap ini juga merupakan alat tangkap yang selektif terhadap hasil tangkapannya. Namun demikian, alat tangkap ini masih menimbulkan suatu masalah dimana ikan hasil tangkapan yang diperoleh tidak semuanya merupakan hasil tangkapan utama (target species, ada sebagian yang merupakan hasil tangkapan sampingan (by-catch. Sebagian besar hasil tangkapan sampingan tuna longline memiliki nilai ekonomis, hanya jenis pari lumpur dan ikan naga yang tidak memiliki nilai ekonomis. Namun demikian, justru yang tidak memiliki nilai ekonomis mendominasi hasil tangkapan sampingan pada perikanan tuna longline. Oleh karena itu perlu adanya tindak lanjut dengan menyusun peraturan atau regulasi yang terkait dengan pengelolaan ikan hasil tangkapan sampingan dan pengelolaan yang benar terhadap hasil tangkapan tersebut beserta habitatnya agar terjaga kelestarian sumberdayanya dan juga tetap menjadi sumber pendapatan masyarakat.Tulisan ini membahas secara ringkas tentang isu hasil tangkapan sampingan pada perikanan tuna longline, komposisi jenisnya, pemanfaatannya dan kebijakannya. Tuna longline is one of the most effective fishing gears to catch tuna. In addition, this fishing gear is selective to catch tuna. However, this gear is still causing a problem where some species other than their target species were caught as by-catch. Most of by-catch species from the tuna longliners have an economic value, except pelagic stingrays and lancetfish. In fact, these by-catch species (non economical-valued species dominated the longline catch. Therefore, it is needed to develop rules or regulations related to the management of the fish by-products, and properly manage the fishing activities on these by-catch species and habitat preservation to preserve its resources and also remain as a source of income. This paper briefly discusses the issue of by

Molecular systematics of the freshwater stingrays (myliobatiformes: potamotrygonidae) of the Amazon, Orinoco, Magdalena, Esequibo, Caribbean, and Maracaibo basins (Colombia - Venezuela): evidence from three mitochondrial genes.

Science.gov (United States)

Garcia, David Alejandro; Lasso, Carlos Andres; Morales, Monica; Caballero, Susana Josefina

2016-11-01

Lack of adequate information about the taxonomic and evolutionary relationships, ecology, biology, and distribution of several species belonging to the family Potamotrygonidae makes these species vulnerable to anthropic activities, including commercial overexploitation for the ornamental fish market. The aim of this study was to investigate the systematic relationships among genera and species belonging to this family by analyses of three mitochondrial gene regions. Samples were collected from the main river basins in Colombia and Venezuela for four genera and seven species of the family, as well as for what appear to be unidentified species. Three mitochondrial molecular markers COI, Cytb, and ATP6 were amplified and sequenced. Maximum likelihood and Bayesian inference analysis were performed to obtain topologies for each marker and for a concatenated dataset including the three genes. Small dataset may compromise some methods estimations of sequence divergence in the ATP6 marker. Monophyly of the four genera in Potamotrygonidae was confirmed and phylogenetic relationships among members of the Potamotrygon genus were not clearly resolved. However, results obtained with the molecular marker Cytb appear to offer a good starting point to differentiate among genera and species as a tool that could be used for barcoding. The application of this gene as a barcode could be applied for management and regulation of extraction practices for these genera. Sequencing complete mitochondrial genomes would be the next step for testing evolutionary hypothesis among these genera. Population structure analyses should be undertaken for Paratrygon, Potamotrygon magdalenae and motoro.

Indiscriminate Fisheries: Understanding the Foodweb of the Great Tonle Sap Lake, Cambodia

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Hannah, L.; Kaufman, L.

2014-12-01

Indiscriminate fisheries target multiple species with multiple gear types. In contrast to well-studied, industrialized single-species, single-gear fisheries, little theory and little but growing literature on practice exists for indiscriminate fisheries. Indiscriminate fisheries are disproportionately important in low-income countries, providing most of the animal protein intake in countries such as Cambodia and Bangladesh. Indiscriminate fisheries may be either freshwater or marine, but here we focus on what may be the largest freshwater indiscriminate fishery in the world. Cambodia's freshwater fishery stands out because it provides the majority of animal protein to over 3 million people living in poverty. The fishery of the Tonle Sap lake is one of the largest, if not the largest contributor to this freshwater fish take, and is perhaps the largest freshwater fishery in the world. In contrast to its importance, very little is known about the foodweb ecology of this system, or how community management which now governs the entire fishery, interacts with biological and physical factors such as climate change.The foodweb of the Tonle Sap has changed dramatically due to high fishing pressure. A system that once harbored giant catfish, barbs and stingrays is now dominated by fish under 20cm in length. The simplification of the system may not have reduced its productivity. Theory of indiscriminate fisheries suggests that r-selected species may be favored and that biomass available for harvest may be maximized, while being more sensitive to environmental fluctuations such as climate change due to food web simplification. The r-selection and size predictions of theory have been confirmed by observations of the Tonle Sap. Early model results suggest sensitivity to environmental stochasticity. The interaction of these ecological changes with social systems will be tested in the Tonle Sap. Fisheries management across the lake has been transferred to community management

Elemental markers in elasmobranchs: effects of environmental history and growth on vertebral chemistry.

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Smith, Wade D; Miller, Jessica A; Heppell, Selina S

2013-01-01

Differences in the chemical composition of calcified skeletal structures (e.g. shells, otoliths) have proven useful for reconstructing the environmental history of many marine species. However, the extent to which ambient environmental conditions can be inferred from the elemental signatures within the vertebrae of elasmobranchs (sharks, skates, rays) has not been evaluated. To assess the relationship between water and vertebral elemental composition, we conducted two laboratory studies using round stingrays, Urobatis halleri, as a model species. First, we examined the effects of temperature (16°, 18°, 24°C) on vertebral elemental incorporation (Li/Ca, Mg/Ca, Mn/Ca, Zn/Ca, Sr/Ca, Ba/Ca). Second, we tested the relationship between water and subsequent vertebral elemental composition by manipulating dissolved barium concentrations (1x, 3x, 6x). We also evaluated the influence of natural variation in growth rate on elemental incorporation for both experiments. Finally, we examined the accuracy of classifying individuals to known environmental histories (temperature and barium treatments) using vertebral elemental composition. Temperature had strong, negative effects on the uptake of magnesium (DMg) and barium (DBa) and positively influenced manganese (DMn) incorporation. Temperature-dependent responses were not observed for lithium and strontium. Vertebral Ba/Ca was positively correlated with ambient Ba/Ca. Partition coefficients (DBa) revealed increased discrimination of barium in response to increased dissolved barium concentrations. There were no significant relationships between elemental incorporation and somatic growth or vertebral precipitation rates for any elements except Zn. Relationships between somatic growth rate and DZn were, however, inconsistent and inconclusive. Variation in the vertebral elemental signatures of U. halleri reliably distinguished individual rays from each treatment based on temperature (85%) and Ba exposure (96%) history. These

Invasive Lionfish (Pterosis volitans) Pose Public Health Threats.

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Diaz, James H

2015-01-01

health threats that include (1) serving as the second most common cause of venomous fish puncture injuries next to stingrays; (2) interrupting the marine seafood chain on reef systems that support commercial fisheries; and (3) bioconcentrating heat-stable algal toxins capable of causing CFP.

Effects of EMF Emissions from Cables and Junction Boxes on Marine Species

Energy Technology Data Exchange (ETDEWEB)

Dhanak, Manhar [Florida Atlantic Univ., Boca Raton, FL (United States); Spieler, Richard [Nova Southeastern Univ., Fort Lauderdale, FL (United States); Kilfoyle, Kirk [Nova Southeastern Univ., Fort Lauderdale, FL (United States); Jermain, Robert F. [Nova Southeastern Univ., Fort Lauderdale, FL (United States); Frankenfield, John [Florida Atlantic Univ., Boca Raton, FL (United States); Ravenna, Shirley [Florida Atlantic Univ., Boca Raton, FL (United States); Dibiasio, Christopher [Florida Atlantic Univ., Boca Raton, FL (United States); Coulson, Robert [Florida Atlantic Univ., Boca Raton, FL (United States); Henderson, Ed [Florida Atlantic Univ., Boca Raton, FL (United States); Venezia, William [Naval Surface Warfare Center (NSWC), Carderock Division (United States)

2016-09-29

Studies have shown that diverse aquatic species are electrosensitive. Many fishes, and marine mammals, can either detect, navigate by, or are affected by electromagnetic fields (EMF) with various sensitivities, and their behavior may be impacted by unnatural EMF emissions in the water column. Sharks, rays and skates are known to have the highest sensitivity to electric fields. Electric field emissions in the range 0.5–100 micro volt/m appear to attract them, and emissions over 100 micro volt/m to repulse them. A marine hydrokinetic MHK device will have multiple components and associated multiple submarine cables on the seafloor and running through the water column and would potentially increase the level of EMF emissions to which the marine species at the site may be exposed to. There are therefore concerns amongst stakeholders that EMF emissions associated with MHK devices and their components may act as barriers to species migration, cause disorientation, change community compositions and ecosystems, and that they may attract sharks, leading to a local increase in the risk of shark attacks. However, field data to validate and model potential relationships between observed responses and the EMF emissions in situ are sparse. A program of experimental field surveys were conducted off the coast of South Florida, USA to characterize the electromagnetic field (EMF) emissions in the water column from a submarine cable, and to monitor for responses of local aquatic species. The field surveys were conducted at the South Florida Ocean Measurement Facility (SFOMF) off Fort Lauderdale, which is a cabled offshore in-water navy range. It consists of multiple active submarine power cables and a number of junction boxes, with the capability to transmit AC/DC power at a range of strength and frequencies. The site includes significant marine life activities and community structure, including highly mobile species, such as sharks, stingrays, mammals and turtles. SFOMF therefore

Improved age control on early Homo fossils from the upper Burgi Member at Koobi Fora, Kenya.

Science.gov (United States)

Joordens, Josephine C A; Dupont-Nivet, Guillaume; Feibel, Craig S; Spoor, Fred; Sier, Mark J; van der Lubbe, Jeroen H J L; Nielsen, Trine Kellberg; Knul, Monika V; Davies, Gareth R; Vonhof, Hubert B

2013-12-01

To address questions regarding the evolutionary origin, radiation and dispersal of the genus Homo, it is crucial to be able to place the occurrence of hominin fossils in a high-resolution chronological framework. The period around 2 Ma (millions of years ago) in eastern Africa is of particular interest as it is at this time that a more substantial fossil record of the genus Homo is first found. Here we combine magnetostratigraphy and strontium (Sr) isotope stratigraphy to improve age control on hominin-bearing upper Burgi (UBU) deposits in Areas 105 and 131 on the Karari Ridge in the eastern Turkana Basin (Kenya). We identify the base of the Olduvai subchron (bC2n) plus a short isolated interval of consistently normal polarity that we interpret to be the Pre-Olduvai event. Combined with precession-forced (~20 kyr [thousands of years]) wet-dry climate cycles resolved by Sr isotope ratios, the magnetostratigraphic data allow us to construct an age model for the UBU deposits. We provide detailed age constraints for 15 hominin fossils from Area 131, showing that key specimens such as cranium KNM-ER 1470, partial face KNM-ER 62000 and mandibles KNM-ER 1482, KNM-ER 1801, and KNM-ER 1802 can be constrained between 1.945 ± 0.004 and 2.058 ± 0.034 Ma, and thus older than previously estimated. The new ages are consistent with a temporal overlap of two species of early Homo that can be distinguished by their facial morphology. Further, our results show that in this time interval, hominins occurred throughout the wet-dry climate cycles, supporting the hypothesis that the lacustrine Turkana Basin was a refugium during regionally dry periods. By establishing the observed first appearance datum of a marine-derived stingray in UBU deposits at 2.058 ± 0.034 Ma, we show that at this time the Turkana Basin was hydrographically connected to the Indian Ocean, facilitating dispersal of fauna between these areas. From a biogeographical perspective, we propose that the Indian Ocean

KAJIAN EFEK MULTIPLIER PRODUK UNGGULAN BERBASIS KLUSTER UKM PENGOLAHAN IKAN ASAP

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Yusmar Ardhi Hidayat

2015-05-01

Full Text Available The purpose of this research are to analyze scale of production of leading commodities and multiplier effect of cultivation and smoked fish in Wonosari, Bonang Demak. This research applies census method in collecting data from all business unit which identified as leading commodities in Wirosari Village, Bonang, Demak Regency. Regarding survey conducted, there are 18 catfish breeders and 49 smoked fish small business used as respondent. Primary data used in this research are rate of production in basis goods, land area, capital, raw materials, manpower, and income multiplier. To support empirical discussion, tools of analysis used in this research are descriptive statistics and income multiplier. Results of this research are primary commodities in Wonosari Village are smoked fish and fresh cat fish. Total production of smoked fish reaches 6.4 Ton each day for with type of smoked fish such as river cat fish, tongkol, sting-ray, cat fish, and other river fish. Meanwhile total production of catfish breeding reaches 105 Ton in first harvest after 2-3 months. Based on that number, smoked fish business promise higher profit than profits catfish breeding. Tujuan penelitian ini adalah menganalisis tingkat produksi dan efek multiplier produk unggulan budidaya dan pengasapan ikan di Desa Wonosari, Bonang Kabupaten Demak. Penelitian mengunakan metode sensus dengan mencari data dari semua unit usaha yang merupakan produk unggulan di Desa Wirosari, Bonang Kecamatan Demak. Responden yang diperoleh sejumlah 18 pembudidaya ikan dan 49 usaha pengasapan ikan. Data primer yang akan digunakan yaitu data jumlah produksi komoditas unggulan, luas lahan, jumlah modal, bahan baku, tenaga kerja, dan multiplier pendapatan. Alat analisis yang digunakan dalam penelitian ini adalah statistik deskriptif, dan indeks multiplier pendapatan. Hasil penelitian menunjukkan bahwa komoditas unggulan Desa Wonosari Kecamatan Bonang Kabupaten Demak adalah Ikan Asap dan Budidaya Ikan Lele

Apatite mineralization in elasmobranch skeletons via a polyphosphate intermediate

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Omelon, Sidney; Lacroix, Nicolas; Lildhar, Levannia; Variola, Fabio; Dean, Mason

2014-05-01

All vertebrate skeletons are stiffened with apatite, a calcium phosphate mineral. Control of apatite mineralization is essential to the growth and repair of the biology of these skeletons, ensuring that apatite is deposited in the correct tissue location at the desired time. The mechanism of this biochemical control remains debated, but must involve increasing the localized apatite saturation state. It was theorized in 1923 that alkaline phosphatase (ALP) activity provides this control mechanism by increasing the inorganic phosphate (Pi) concentration via dephosphorylation of phosphorylated molecules. The ALP substrate for biological apatite is not known. We propose that polyphosphates (polyPs) produced by mitochondria may be the substrate for biological apatite formation by ALP activity. PolyPs (PO3-)n, also known as condensed phosphates, represent a concentrated, bioavailable Pi-storage strategy. Mitochondria import Pi and synthesize phosphate polymers through an unknown biochemical mechanism. When chelated with calcium and/or other cations, the effective P-concentration of these neutrally charged, amorphous, polyP species can be very high (~ 0.5 M), without inducing phosphate mineral crystallization. This P-concentration in the low Pi-concentration biological environment offers a method of concentrating P well above an apatite supersaturation required for nucleation. Bone is the most studied mineralized skeletal tissue. However, locating and analyzing active mineralizing areas is challenging. We studied calcified cartilage skeletons of elasmobranch fishes (sharks, stingrays and relatives) to analyse the phosphate chemistry in this continually mineralizing skeleton. Although the majority of the elasmobranch skeleton is unmineralized cartilage, it is wrapped in an outer layer of mineralized tissue comprised of small tiles called tesserae. These calcified tesserae continually grow through the formation of new mineral on their borders. Co-localization of ALP and

The venomous toadfish Thalassophryne nattereri (niquim or miquim: report of 43 injuries provoked in fishermen of Salinópolis (Pará State and Aracaju (Sergipe State, Brazil O peixe-sapo venenoso Thalassophryne nattereri (niquim ou miquim: relato de 43 acidentes provocados em pescadores de Salinópolis (Pará e Aracaju (Sergipe, Brasil

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Vidal Haddad Junior

2003-08-01

Full Text Available Fishes of family Batrachoididae are responsible for great number of injuries in fishermen in North and Northeast regions of Brazil. The genus Thalassophryne presents various venomous species of fishes found in the Brazilian coast, T. nattereri being the most common of them. The venom is ejected through two hollow spines on the dorsal fin and two on pre-opercular regions, which present a venomous gland in the base and can be erected or depressed by the fish. The manifestations of the envenoming were intense local pain, edema and erythema in 43 patients observed in Salinópolis (Pará State and Aracaju (Sergipe State. There were no systemic manifestations, but necrosis was detected in eight and bacterial infection in ten injured fishermen. The circumstances of the contacts and therapeutic aspects are discussed. Envenoming by the genus Thalassophryne is important and frequent and should be considered of moderate severity grade, since there are not the excruciating pain or the massive local necrosis provoked by scorpionfishes (Scorpaena or stingrays injuries nor the systemic manifestations that are the most important marker of severe envenoming.Os peixes da família Batrachoididae causam um grande número de acidentes em pescadores das regiões Norte e Nordeste do Brasil. O gênero Thalassophryne apresenta várias espécies no Brasil e a espécie Thalassophryne nattereri é a mais comum, todas apresentando veneno. O veneno é inoculado por duas espículas ocas na nadadeira dorsal e duas nas regiões pré-operculares, ligadas a uma glândula de veneno na base. Os envenenamentos causaram dor intensa, edema e eritema iniciais em 43 pescadores observados em Salinópolis (Pará e Aracaju (Sergipe. Em todos os casos, não ocorreram fenômenos sistêmicos dignos de nota, mas ocorreu necrose local em oito pacientes e infecção bacteriana em dez. As circunstâncias dos acidentes são comentadas, assim como aspectos terapêuticos. Nossa conclusão foi que o

Diet of the freshwater stingray Potamotrygon motoro (Chondrichthyes: Potamotrygonidae on Marajó Island (Pará, Brazil Dieta da raia de água doce Potamotrygon motoro (Chondrichthyes: Potamotrygonidae na Ilha de Marajó (Pará, Brasil

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MP. Almeida

2010-02-01

Full Text Available The stomach contents of 137 examples of Potamotrygon motoro caught in 3 locations (Muaná, Afuá and Lake Arari on Marajó Island were analysed. The values of the Index of Relative Importance (IRI and its respective percentage (%IRI were calculated. The level of repletion 1 (¼ full was the most representative for both sexes, as well as for immature and mature specimens. Most of the food items found were well-digested. The food items identification indicated the presence of 15 orders, including insects, mollusks, crustaceans, annelids and fish. Differences in diet were observed among the locations studied when comparing %IRI, crustaceans being the most preferred in Afuá, fish in Lake Arari and mollusks in Muaná.O conteúdo estomacal de 137 exemplares de Potamotrygon motoro provenientes de 3 localidades (Muaná, Afuá e Lago Arari na ilha de Marajó foi analisado. Os valores do Índice Relativo de Importância (IRI e respectiva porcentagem (%IRI foram calculados. O nível de repleção 1 (¼ cheio foi o mais representativo para ambos os sexos, assim como para exemplares imaturos e maduros. A maioria dos itens alimentares analisados encontrava-se bastante digerido. A identificação dos itens alimentares indicou a presença de 15 ordens, incluindo insetos, moluscos, crustáceos, anelídeos e peixes. Diferenças na dieta entre os locais amostrados foram observadas ao se comparar as %IRI, sendo crustáceos o item preferencial em Afuá, peixes no Lago Arari e moluscos em Muaná.

Notes on the Bull shark Carcharhinus leucas in the lagoon region of Cananéia, Brazil

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V Sadowsky

1971-12-01

tamanhos oscilaram ent re 768-812 mm. O comprimento do menor jovem livre encontrado foi de 697 mm, sendo que jovens de presumivelmente 9 a 12 meses têm de 98 a 112 cm; entre 21 e 24 meses alcançam 124 a 128 cm, ou seja, os tamanhos que apresentam quando emigram para mar aberto. Não ficou confirmado o fenômeno da inibição alimentar nas fêmeas capturadas, já observado em genetrizes da mesma espécie durante o período de parição no delta do Mississippi. O conteúdo estomacal apresentou, por ordem decrescente de abundância: Arius spixii (13; Chloroscombrus chrysurus (7; A. grandicassus (6; A. barbus (4; Felichtys marinus (3; Genidens genide ns (2; Chanophorus tajacica (2; Carcharhinus porosus (2; Conodon nobilis, Caranx crysos, scomberomorus maculatus, Sphyrna tiburo, Rhinoptera brasiliensis, Dasyatis americana, Diapterus rhombeus (1, além de cerca de 25/30 exemplares de Callinectes sp.

Morfometria de raias continentais (Chondrichthyes, Potamotrygonidae do alto rio Paraná, Brasil - DOI: 10.4025/actascibiolsci.v29i4.885 Morphometry of upper Paraná river freshwater stingrays (Chondrichthyes, Potamotrygonidae - DOI: 10.4025/actascibiolsci.v29i4.885

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Erivelto Goulart

2008-02-01

Full Text Available Potamotrygonidae constitui o único grupo recente de Chondrichthyes cujo habitat está restrito, exclusivamente, a águas continentais. Na planície de inundação do Alto rio Paraná, espécies desta família estabeleceram-se após o fechamento das comportas da usina hidrelétrica de Itaipu, a jusante. O objetivo deste trabalho foi, utilizando medidas corporais, identificar diferenças morfométricas entre indivíduos de Potamotrygon cf. motoro (Natterer in Müller & Henle, 1841 e Potamotrygon falkneri Castex & Maciel, 1963 capturados nesta região, bem como estimar o tamanho com que machos destas espécies atingem a maturidade gonadal. Machos de P. falkneri e P. cf. motoro das populações avaliadas atingem a maturidade gonadal com largura do disco variando em torno de 26 cm e 23 cm, respectivamente. Na comparação das espécies, P. cf. motoro apresentou maior distância proporcional entre as narinas e maior comprimento proporcional da cauda e dos espiráculos. Identificou-se dimorfismo sexual secundário para P. falkneri, consistindo da presença de fileiras laterais de espinhos na cauda das fêmeas. Estudos futuros de morfologia funcional e ecomorfologia poderão esclarecer o significado das diferenças morfométricas para o modo de vida destas espécies.Potamotrygonidae is the only extant chondrichthyan group restricted exclusively to freshwater. This family invaded the Upper Paraná river system after the closing of Itaipu Dam. This study aimed to identify morphometric differences between Potamotrygon cf. motoro (Natterer in Müller & Henle, 1841 and Potamotrygon falkneri Castex & Maciel, 1963 sampled in that area, and estimate male size at gonadal maturation. P. falkneri and P. cf. motoro males reach gonadal maturation at 26 cm and 23 cm disc width, respectively. Comparing both species, P. cf. motoro presented larger tail, spiracles and distance between nostrils. Lateral small stings on tails of P. falkneri females were observed as secondary sexual dimorphism. Further studies on functional morphology and ecomorphology may point the meaning of morphometric differences to these species’ ecological interactions.