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Sample records for octopus wunderpus photogenicus

  1. Individually Unique Body Color Patterns in Octopus (Wunderpus photogenicus) Allow for Photoidentification

    PubMed Central

    Huffard, Christine L.; Caldwell, Roy L.; DeLoach, Ned; Gentry, David Wayne; Humann, Paul; MacDonald, Bill; Moore, Bruce; Ross, Richard; Uno, Takako; Wong, Stephen

    2008-01-01

    Studies on the longevity and migration patterns of wild animals rely heavily on the ability to track individual adults. Non-extractive sampling methods are particularly important when monitoring animals that are commercially important to ecotourism, and/or are rare. The use of unique body patterns to recognize and track individual vertebrates is well-established, but not common in ecological studies of invertebrates. Here we provide a method for identifying individual Wunderpus photogenicus using unique body color patterns. This charismatic tropical octopus is commercially important to the underwater photography, dive tourism, and home aquarium trades, but is yet to be monitored in the wild. Among the adults examined closely, the configurations of fixed white markings on the dorsal mantle were found to be unique. In two animals kept in aquaria, these fixed markings were found not to change over time. We believe another individual was photographed twice in the wild, two months apart. When presented with multiple images of W. photogenicus, volunteer observers reliably matched photographs of the same individuals. Given the popularity of W. photogenicus among underwater photographers, and the ease with which volunteers can correctly identify individuals, photo-identification appears to be a practical means to monitor individuals in the wild. PMID:19009019

  2. Octopus

    SciTech Connect

    Strubbe, David

    2015-05-26

    Octopus is a scientific program aimed at the ab initio virtual experimentation on a hopefully ever-increasing range of system types. Electrons are described quantum-mechanically within density-functional theory (DFT), in its time-dependent form (TDDFT) when doing simulations in time. Nuclei are described classically as point particles. Electron-nucleus interaction is described within the pseudopotential approximation.

  3. Octopus automutilation syndrome.

    PubMed

    Reimschuessel, R; Stoskopf, M K

    1990-05-01

    This paper describes an automutilation syndrome (OAS) in three species of captive octopuses, Octopus dolfleini, O. bimaculoides, and O. maya, characterized by external arm and mantle lesions. Three clinical patterns in nine animals had similar and characteristic gross and histopathologic features. Axial nerve or brachial artery lesions were observed in six of the nine cases and vascular lesions were seen in two of eight cases with mantle ulcerations. A relationship between automutilation in the octopus and dysesthesias due to neural or vascular pathology is proposed. PMID:2351844

  4. Experimental evidence for spatial learning on octopuses (octopus bimaculoides).

    PubMed

    Boal, J G; Dunham, A W; Williams, K T; Hanlon, R T

    2000-09-01

    Octopuses forage far from temporary home dens to which they return for shelter. Spatial tasks may assess learning. Octopuses (Octopus bimaculoides) were placed in a novel arena, and their movements were tracked for 72 hr. Movements around the arena decreased across time, consistent with exploratory learning. Next, octopuses were given 23 hr to move around an arena; after a 24-hr delay, their memory of a burrow location was tested. Most remembered the location of the open burrow, demonstrating learning in 1 day. Finally, octopuses were trained to locate a single open escape burrow among 6 possible locations. Retention was tested after a week and was immediately followed by reversal training (location rotated 180 degrees ). Octopuses learned the original location of the burrow, remembering it for a week. Path lengths increased significantly after reversal, gradually improving and showing relearning. Octopuses show exploratory behavior, learning, and retention of spatial information.

  5. Cornea regeneration in the Pacific giant octopus, Octopus dofleini, and the common octopus, O. vulgaris.

    PubMed

    Dingerkus, G; Santoro, E D

    1981-04-15

    Cornea regeneration in a Pacific giant octopus, Octopus dofleini, occurred within 10 days after the injury was observed. Surgical removal of the cornea in a common octopi, O. vulgaris experimentally duplicated this cornea regeneration within a 10-day period. It is, therefore, concluded that besides sucking discs, arms, and nerve fibres, octopi can also regenerate corneal tissue. PMID:7238810

  6. Cornea regeneration in the Pacific giant octopus, Octopus dofleini, and the common octopus, O. vulgaris.

    PubMed

    Dingerkus, G; Santoro, E D

    1981-04-15

    Cornea regeneration in a Pacific giant octopus, Octopus dofleini, occurred within 10 days after the injury was observed. Surgical removal of the cornea in a common octopi, O. vulgaris experimentally duplicated this cornea regeneration within a 10-day period. It is, therefore, concluded that besides sucking discs, arms, and nerve fibres, octopi can also regenerate corneal tissue.

  7. The toxicology of Octopus maculosa: the blue-ringed octopus.

    PubMed

    Bonnet, M S

    1999-10-01

    The biotoxicology of the Australian blue-ringed octopus is detailed with the view of introducing it as a remedy into the homoeopathic Materia Medica and stimulating the second step of proving this venom. PMID:10582647

  8. Signal Use by Octopuses in Agonistic Interactions.

    PubMed

    Scheel, David; Godfrey-Smith, Peter; Lawrence, Matthew

    2016-02-01

    Cephalopods show behavioral parallels to birds and mammals despite considerable evolutionary distance [1, 2]. Many cephalopods produce complex body patterns and visual signals, documented especially in cuttlefish and squid, where they are used both in camouflage and a range of interspecific interactions [1, 3-5]. Octopuses, in contrast, are usually seen as solitary and asocial [6, 7]; their body patterns and color changes have primarily been interpreted as camouflage and anti-predator tactics [8-12], though the familiar view of the solitary octopus faces a growing list of exceptions. Here, we show by field observation that in a shallow-water octopus, Octopus tetricus, a range of visible displays are produced during agonistic interactions, and these displays correlate with the outcome of those interactions. Interactions in which dark body color by an approaching octopus was matched by similar color in the reacting octopus were more likely to escalate to grappling. Darkness in an approaching octopus met by paler color in the reacting octopus accompanied retreat of the paler octopus. Octopuses also displayed on high ground and stood with spread web and elevated mantle, often producing these behaviors in combinations. This study is the first to document the systematic use of signals during agonistic interactions among octopuses. We show prima facie conformity of our results to an influential model of agonistic signaling [13]. These results suggest that interactions have a greater influence on octopus evolution than has been recognized and show the importance of convergent evolution in behavioral traits. PMID:26832440

  9. Signal Use by Octopuses in Agonistic Interactions.

    PubMed

    Scheel, David; Godfrey-Smith, Peter; Lawrence, Matthew

    2016-02-01

    Cephalopods show behavioral parallels to birds and mammals despite considerable evolutionary distance [1, 2]. Many cephalopods produce complex body patterns and visual signals, documented especially in cuttlefish and squid, where they are used both in camouflage and a range of interspecific interactions [1, 3-5]. Octopuses, in contrast, are usually seen as solitary and asocial [6, 7]; their body patterns and color changes have primarily been interpreted as camouflage and anti-predator tactics [8-12], though the familiar view of the solitary octopus faces a growing list of exceptions. Here, we show by field observation that in a shallow-water octopus, Octopus tetricus, a range of visible displays are produced during agonistic interactions, and these displays correlate with the outcome of those interactions. Interactions in which dark body color by an approaching octopus was matched by similar color in the reacting octopus were more likely to escalate to grappling. Darkness in an approaching octopus met by paler color in the reacting octopus accompanied retreat of the paler octopus. Octopuses also displayed on high ground and stood with spread web and elevated mantle, often producing these behaviors in combinations. This study is the first to document the systematic use of signals during agonistic interactions among octopuses. We show prima facie conformity of our results to an influential model of agonistic signaling [13]. These results suggest that interactions have a greater influence on octopus evolution than has been recognized and show the importance of convergent evolution in behavioral traits.

  10. Interspecific evaluation of octopus escape behavior.

    PubMed

    Wood, James B; Anderson, Roland C

    2004-01-01

    The well-known ability of octopuses to escape enclosures is a behavior that can be fatal and, therefore, is an animal welfare issue. This study obtained survey data from 38 participants-primarily scientists and public aquarists who work with octopuses-on 25 described species of octopus. The study demonstrates that the likeliness to escape is species specific (p =.001). The study gives husbandry techniques to keep captive octopuses contained. This first interspecific study of octopus escape behavior allows readers to make informed species-specific husbandry choices.

  11. Contrasting activity patterns of two related octopus species, Octopus macropus and Octopus vulgaris.

    PubMed

    Meisel, Daniela V; Byrne, Ruth A; Kuba, Michael; Mather, Jennifer; Ploberger, Werner; Reschenhofer, Erhard

    2006-08-01

    Octopus macropus and Octopus vulgaris have overlapping habitats and are exposed to similar temporal changes. Whereas the former species is described as nocturnal in the field, there are conflicting reports about the activity time of the latter one. To compare activity patterns, the authors tested both species in the laboratory. Octopuses were exposed to a light-dark cycle and held under constant dim light for 7 days each. O. macropus showed nocturnal and light-cued activity. According to casual observations, O. vulgaris started out nocturnal but had switched to mostly diurnal when the experiment began. Individual variation of its activity was found. The different activity patterns of O. macropus and O. vulgaris might reflect their lifestyles, the latter species being more generalist.

  12. Octopuses (Enteroctopus dofleini) recognize individual humans.

    PubMed

    Anderson, Roland C; Mather, Jennifer A; Monette, Mathieu Q; Zimsen, Stephanie R M

    2010-01-01

    This study exposed 8 Enteroctopus dofleini separately to 2 unfamiliar individual humans over a 2-week period under differing circumstances. One person consistently fed the octopuses and the other touched them with a bristly stick. Each human recorded octopus body patterns, behaviors, and respiration rates directly after each treatment. At the end of 2 weeks, a body pattern (a dark Eyebar) and 2 behaviors (reaching arms toward or away from the tester and funnel direction) were significantly different in response to the 2 humans. The respiration rate of the 4 larger octopuses changed significantly in response to the 2 treatments; however, there was no significant difference in the 4 smaller octopuses' respiration. Octopuses' ability to recognize humans enlarges our knowledge of the perceptual ability of this nonhuman animal, which depends heavily on learning in response to visual information. Any training paradigm should take such individual recognition into consideration as it could significantly alter the octopuses' responses.

  13. Octopuses (Enteroctopus dofleini) recognize individual humans.

    PubMed

    Anderson, Roland C; Mather, Jennifer A; Monette, Mathieu Q; Zimsen, Stephanie R M

    2010-01-01

    This study exposed 8 Enteroctopus dofleini separately to 2 unfamiliar individual humans over a 2-week period under differing circumstances. One person consistently fed the octopuses and the other touched them with a bristly stick. Each human recorded octopus body patterns, behaviors, and respiration rates directly after each treatment. At the end of 2 weeks, a body pattern (a dark Eyebar) and 2 behaviors (reaching arms toward or away from the tester and funnel direction) were significantly different in response to the 2 humans. The respiration rate of the 4 larger octopuses changed significantly in response to the 2 treatments; however, there was no significant difference in the 4 smaller octopuses' respiration. Octopuses' ability to recognize humans enlarges our knowledge of the perceptual ability of this nonhuman animal, which depends heavily on learning in response to visual information. Any training paradigm should take such individual recognition into consideration as it could significantly alter the octopuses' responses. PMID:20563906

  14. Underwater bipedal locomotion by octopuses in disguise.

    PubMed

    Huffard, Christine L; Boneka, Farnis; Full, Robert J

    2005-03-25

    Here we report bipedal movement with a hydrostatic skeleton. Two species of octopus walk on two alternating arms using a rolling gait and appear to use the remaining six arms for camouflage. Octopus marginatus resembles a coconut, and Octopus (Abdopus) aculeatus, a clump of floating algae. Using underwater video, we analyzed the kinematics of their strides. Each arm was on the sand for more than half of the stride, qualifying this behavior as a form of walking.

  15. Octopus movement: push right, go left.

    PubMed

    Hooper, Scott L

    2015-05-01

    Octopus arms have essentially infinite degrees of freedom. New research shows that, despite this potentially great complexity, to locomote octopuses simply elongate one or more arms, thus pushing the body in the opposite direction, and do so without activating the arms in an ordered pattern.

  16. Octopus movement: push right, go left.

    PubMed

    Hooper, Scott L

    2015-05-01

    Octopus arms have essentially infinite degrees of freedom. New research shows that, despite this potentially great complexity, to locomote octopuses simply elongate one or more arms, thus pushing the body in the opposite direction, and do so without activating the arms in an ordered pattern. PMID:25942549

  17. Does Octopus vulgaris have preferred arms?

    PubMed

    Byrne, Ruth A; Kuba, Michael J; Meisel, Daniela V; Griebel, Ulrike; Mather, Jennifer A

    2006-08-01

    Previous behavioral studies in Octopus vulgaris revealed lateralization of eye use. In this study, the authors expanded the scope to investigate arm preferences. The octopus's generalist hunting lifestyle and the structure of their arms suggest that these animals have no need to designate specific arms for specific tasks. However, octopuses also show behaviors, like exploration, in which only single or small groups of arms are involved. Here the authors show that octopuses had a strong preference for anterior arm use to reach for and explore objects, which points toward a task division between anterior and posterior arms. Four out of 8 subjects also showed a lateral bias. In addition, octopuses had a preference for a specific arm to reach into a T maze to retrieve a food reward. These findings give evidence for limb-specialization in an animal whose 8 arms were believed to be equipotential.

  18. Cannibalistic behavior of octopus (Octopus vulgaris) in the wild.

    PubMed

    Hernández-Urcera, Jorge; Garci, Manuel E; Roura, Alvaro; González, Angel F; Cabanellas-Reboredo, Miguel; Morales-Nin, Beatriz; Guerra, Angel

    2014-11-01

    The first description of cannibalism in wild adult Octopus vulgaris is presented from 3 observations made in the Ría de Vigo (NW Spain), which were filmed by scuba divers. These records document common traits in cannibalistic behavior: (a) it was intercohort cannibalism; (b) attacks were made by both males and females; (c) in 2 of the records, the prey were transported to the den, which was covered with stones of different sizes; (d) the predator started to eat the tip of the arms of its prey; (e) predation on conspecifics occurred even if there were other abundant prey available (i.e., mussels); and (f) the prey/predator weight ratio in the 3 cases ranged from 20% to 25% body weight. The relationships between this behavior and sex, defense of territory, energy balance, food shortage, competition and predation, as well as how the attacker kills its victim are discussed. PMID:25198542

  19. Cannibalistic behavior of octopus (Octopus vulgaris) in the wild.

    PubMed

    Hernández-Urcera, Jorge; Garci, Manuel E; Roura, Alvaro; González, Angel F; Cabanellas-Reboredo, Miguel; Morales-Nin, Beatriz; Guerra, Angel

    2014-11-01

    The first description of cannibalism in wild adult Octopus vulgaris is presented from 3 observations made in the Ría de Vigo (NW Spain), which were filmed by scuba divers. These records document common traits in cannibalistic behavior: (a) it was intercohort cannibalism; (b) attacks were made by both males and females; (c) in 2 of the records, the prey were transported to the den, which was covered with stones of different sizes; (d) the predator started to eat the tip of the arms of its prey; (e) predation on conspecifics occurred even if there were other abundant prey available (i.e., mussels); and (f) the prey/predator weight ratio in the 3 cases ranged from 20% to 25% body weight. The relationships between this behavior and sex, defense of territory, energy balance, food shortage, competition and predation, as well as how the attacker kills its victim are discussed.

  20. Connecting your Apple to Octopus 7600's

    SciTech Connect

    Barton, G.W. Jr.

    1983-01-17

    In UCID-19588, Communicating between the Apple and the Wang, we described how to take Apple DOS text files and send them to the Wang, and how to return Wang files to the Apple. It is also possible to use your Apple as an Octopus terminal, and to exchange files with Octopus 7600's. Presumably, you can also talk to the Crays, or any other part of the system. This connection has another virtue. It eliminates one of the terminals in your office.

  1. Reproductive traits of the small Patagonian octopus Octopus tehuelchus

    NASA Astrophysics Data System (ADS)

    Storero, Lorena P.; Narvarte, Maite A.; González, Raúl A.

    2012-12-01

    This study evaluated the reproductive features of Octopus tehuelchus in three coastal environments of San Matías Gulf (Patagonia). Monthly samples of O. tehuelchus were used to estimate size at maturity, compare seasonal changes in oocyte size frequency distributions between sites as well as oocyte number and size between female maturity stage and sites. Females in Islote Lobos had a smaller size at maturity than females in San Antonio Bay and El Fuerte, probably as a consequence of a generally smaller body size. Males in San Antonio Bay were smaller at maturity than females. O. tehuelchus is a simultaneous terminal spawner. Fecundity (expressed as number of vitellogenic oocytes in ovary) was lower in Islote Lobos, and an increase in oocyte number in relation to female total weight was found. Females in San Antonio Bay had the largest oocytes, which may indicate higher energy reserves for the embryo and therefore higher juvenile survival. There was a close relationship between reproduction, growth and condition, represented as size at maturity, number and size of vitellogenic oocytes and period of maturity and spawning. Given the local variation in some reproductive features of O. tehuelchus, studies should focus on the environmental factors, which bring about this variation, and on how it affects the dynamics of local populations.

  2. An embodied view of octopus neurobiology.

    PubMed

    Hochner, Binyamin

    2012-10-23

    Octopuses have a unique flexible body and unusual morphology, but nevertheless they are undoubtedly a great evolutionary success. They compete successfully with vertebrates in their ecological niche using a rich behavioral repertoire more typical of an intelligent predator which includes extremely effective defensive behavior--fast escape swimming and an astonishing ability to adapt their shape and color to their environment. The most obvious characteristic feature of an octopus is its eight long and flexible arms, but these pose a great challenge for achieving the level of motor and sensory information processing necessary for their behaviors. First, coordinating motion is a formidable task because of the infinite degrees of freedom that have to be controlled; and second, it is hard to use body coordinates in this flexible animal to represent sensory information in a central control system. Here I will review experimental results suggesting that these difficulties, arising from the animal's morphology, have imposed the evolution of unique brain/body/behavior relationships best explained as intelligent behavior which emerges from the octopus's embodied organization. The term 'intelligent embodiment' comes from robotics and refers to an approach to designing autonomous robots in which the behavior emerges from the dynamic physical and sensory interactions of the agent's materials, morphology and environment. Consideration of the unusual neurobiology of the octopus in the light of its unique morphology suggests that similar embodied principles are instrumental for understanding the emergence of intelligent behavior in all biological systems.

  3. An embodied view of octopus neurobiology.

    PubMed

    Hochner, Binyamin

    2012-10-23

    Octopuses have a unique flexible body and unusual morphology, but nevertheless they are undoubtedly a great evolutionary success. They compete successfully with vertebrates in their ecological niche using a rich behavioral repertoire more typical of an intelligent predator which includes extremely effective defensive behavior--fast escape swimming and an astonishing ability to adapt their shape and color to their environment. The most obvious characteristic feature of an octopus is its eight long and flexible arms, but these pose a great challenge for achieving the level of motor and sensory information processing necessary for their behaviors. First, coordinating motion is a formidable task because of the infinite degrees of freedom that have to be controlled; and second, it is hard to use body coordinates in this flexible animal to represent sensory information in a central control system. Here I will review experimental results suggesting that these difficulties, arising from the animal's morphology, have imposed the evolution of unique brain/body/behavior relationships best explained as intelligent behavior which emerges from the octopus's embodied organization. The term 'intelligent embodiment' comes from robotics and refers to an approach to designing autonomous robots in which the behavior emerges from the dynamic physical and sensory interactions of the agent's materials, morphology and environment. Consideration of the unusual neurobiology of the octopus in the light of its unique morphology suggests that similar embodied principles are instrumental for understanding the emergence of intelligent behavior in all biological systems. PMID:23098601

  4. Intramantle inking: a stress behavior in Octopus bimaculoides (Mollusca: Cephalopoda).

    PubMed

    Bennett, Heather; Toll, Ronald B

    2011-11-01

    Several Pacific 2-spot octopuses (Octopus bimaculoides) shipped from California and held in a recirculating seawater system at Illinois College exhibited an unusual postshipping stress behavior not previously documented in the literature. Ink, normally ejected into the surrounding seawater, was uncharacteristically retained in the mantle cavity. We describe the resulting behaviors, discuss successful resuscitation efforts, and briefly consider the possible role(s) that ink may have played in the death of one octopus.

  5. Intramantle Inking: A Stress Behavior in Octopus bimaculoides (Mollusca: Cephalopoda)

    PubMed Central

    Toll, Ronald B

    2011-01-01

    Several Pacific 2-spot octopuses (Octopus bimaculoides) shipped from California and held in a recirculating seawater system at Illinois College exhibited an unusual postshipping stress behavior not previously documented in the literature. Ink, normally ejected into the surrounding seawater, was uncharacteristically retained in the mantle cavity. We describe the resulting behaviors, discuss successful resuscitation efforts, and briefly consider the possible role(s) that ink may have played in the death of one octopus. PMID:22330791

  6. Octopuses (Octopus bimaculoides) and cuttlefishes (Sepia pharaonis, S. officinalis) can conditionally discriminate.

    PubMed

    Hvorecny, Lauren M; Grudowski, Jessica L; Blakeslee, Carrie J; Simmons, Tiffany L; Roy, Paula R; Brooks, Jennifer A; Hanner, Rachel M; Beigel, Marie E; Karson, Miranda A; Nichols, Rachel H; Holm, Johanna B; Boal, Jean Geary

    2007-10-01

    In complex navigation using landmarks, an animal must discriminate between potential cues and show context (condition) sensitivity. Such conditional discrimination is considered a form of complex learning and has been associated primarily with vertebrates. We tested the hypothesis that octopuses and cuttlefish are capable of conditional discrimination. Subjects were trained in two maze configurations (the conditions) in which they were required to select one of two particular escape routes within each maze (the discrimination). Conditional discrimination could be demonstrated by selecting the correct escape route in each maze. Six of ten mud-flat octopuses (Octopus bimaculoides), 6 of 13 pharaoh cuttlefish (Sepia pharaonis), and one of four common cuttlefish (S. officinalis) demonstrated conditional discrimination by successfully solving both mazes. These experiments demonstrate that cephalopods are capable of conditional discrimination and extend the limits of invertebrate complex learning.

  7. Infiltrated plaques resulting from an injury caused by the common octopus (Octopus vulgaris): a case report.

    PubMed

    Haddad, Vidal; de Magalhães, Claudia Alves

    2014-01-01

    Several species of octopus are considered venomous due to toxins present in the glands connected to their "beak", which may be associated with hunt and kill of prey. Herein, we report an accident involving a common octopus (Octopus vulgaris) that injured an instructor during a practical biology lesson and provoked an inflamed infiltrated plaque on the hand of the victim. The lesion was present for about three weeks and was treated with cold compresses and anti-inflammatory drugs. It was healed ten days after leaving a hyperchromic macule at the bite site. The probable cause of the severe inflammation was the digestive enzymes of the glands and not the neurotoxins of the venom. PMID:25873938

  8. Neuroethology: self-recognition helps octopuses avoid entanglement.

    PubMed

    Crook, Robyn J; Walters, Edgar T

    2014-06-01

    How an octopus performs complex movements of its eight sucker-studded arms without entanglement has been a mystery. A new study has found that self-recognition of the octopus's skin by its suckers inhibits reflexive grasping of its own arms, simplifying the mechanisms needed to generate intricate arm behavior.

  9. Neuroethology: self-recognition helps octopuses avoid entanglement.

    PubMed

    Crook, Robyn J; Walters, Edgar T

    2014-06-01

    How an octopus performs complex movements of its eight sucker-studded arms without entanglement has been a mystery. A new study has found that self-recognition of the octopus's skin by its suckers inhibits reflexive grasping of its own arms, simplifying the mechanisms needed to generate intricate arm behavior. PMID:24892911

  10. Crystallins of the octopus lens. Recruitment from detoxification enzymes.

    PubMed

    Tomarev, S I; Zinovieva, R D; Piatigorsky, J

    1991-12-15

    The eye lens crystallins of the octopus Octopus dofleini were identified by sequencing abundant proteins and cDNAs. As in squid, the octopus crystallins have subunit molecular masses of 25-30 kDa, are related to mammalian glutathione S-transferases (GST), and are encoded in at least six genes. The coding regions and deduced amino acid sequences of four octopus lens cDNAs are 75-80% identical, while their non-coding regions are entirely different. Deduced amino acid sequences show 52-57% similarity with squid GST-like crystallins, but only 20-25% similarity with mammalian GST. These data suggest that the octopus and squid lens GST-like crystallin gene families expanded after divergence of these species. Northern blot hybridization indicated that the four octopus GST-like crystallin genes examined are lens-specific. Lens extracts showed about 40 times less GST activity using 1-chloro-2,4-dinitrobenzene as substrate than liver extracts of the octopus, indicating that the major GST-like crystallins are specialized for a lens structural role. A prominent 59-kDa crystallin polypeptide, previously observed in octopus but not squid and called omega-crystallin (Chiou, S.-H. (1988) FEBS Lett. 241, 261-264), has been identified as an aldehyde dehydrogenase. Since cytoplasmic aldehyde dehydrogenase is a major protein in elephant shrew lenses (eta-crystallin; Wistow, G., and Kim, H. (1991) J. Mol. Evol. 32, 262-269) the octopus aldehyde dehydrogenase crystallin provides the first example of a similar enzyme-crystallin in vertebrates and invertebrates. The use of detoxification stress proteins (GST and aldehyde dehydrogenase) as cephalopod crystallins indicates a common strategy for recruitment of enzyme-crystallins during the convergent evolution of vertebrate and invertebrate lenses. For historical reasons we propose that the octopus GST-like crystallins, like those of the squid, are called S-crystallins. PMID:1721068

  11. Metal accumulation and oxidative stress biomarkers in octopus (Octopus vulgaris) from Northwest Atlantic.

    PubMed

    Semedo, Miguel; Reis-Henriques, Maria Armanda; Rey-Salgueiro, Ledicia; Oliveira, Marta; Delerue-Matos, Cristina; Morais, Simone; Ferreira, Marta

    2012-09-01

    Metals are ubiquitous in the environment and accumulate in aquatic organisms and are known for their ability to enhance the production of reactive oxygen species (ROS). In aquatic species, oxidative stress mechanisms have been studied by measuring antioxidant enzyme activities and oxidative damages in tissues. The aim of this study was to apply and validate a set of oxidative stress biomarkers and correlate responses with metal contents in tissues of common octopus (Octopus vulgaris). Antioxidant enzyme activity (catalase--CAT, superoxide dismutase--SOD and glutathione S-transferases--GST), oxidative damages (lipid peroxidation--LPO and protein carbonyl content--PCO) and metal content (Cu, Zn, Pb, Cd and As) in the digestive gland and arm of octopus, collected in the NW Portuguese coast in different periods, were assessed after capture and after 14 days in captivity. CAT and SOD activities were highly responsive to fluctuations in metal concentrations and able to reduce oxidative damage, LPO and PCO in the digestive gland. CAT activity was also positively correlated with SOD and GST activities, which emphasizes that the three enzymes respond in a coordinated way to metal induced oxidative stress. Our results validate the use of oxidative stress biomarkers to assess metal pollution effects in this ecological and commercial relevant species. Moreover, octopus seems to have the ability to control oxidative damage by triggering an antioxidant enzyme coordinated response in the digestive gland.

  12. Uptake, transfer and elimination kinetics of paralytic shellfish toxins in common octopus (Octopus vulgaris).

    PubMed

    Lopes, Vanessa M; Baptista, Miguel; Repolho, Tiago; Rosa, Rui; Costa, Pedro Reis

    2014-01-01

    Marine phycotoxins derived from harmful algal blooms are known to be associated with mass mortalities in the higher trophic levels of marine food webs. Bivalve mollusks and planktivorous fish are the most studied vectors of marine phycotoxins. However, field surveys recently showed that cephalopod mollusks also constitute potential vectors of toxins. Thus, here we determine, for the first time, the time course of accumulation and depuration of paralytic shellfish toxins (PSTs) in the common octopus (Octopus vulgaris). Concomitantly, the underlying kinetics of toxin transfer between tissue compartments was also calculated. Naturally contaminated clams were used to orally expose the octopus to PSTs during 6 days. Afterwards, octopus specimens were fed with non-contaminated shellfish during 10 days of depuration period. Toxins reached the highest concentrations in the digestive gland surpassing the levels in the kidney by three orders of magnitude. PSTs were not detected in any other tissue analyzed. Net accumulation efficiencies of 42% for GTX5, 36% for dcSTX and 23% for C1+2 were calculated for the digestive gland. These compounds were the most abundant toxins in both digestive gland and the contaminated shellfish diet. The small differences in relative abundance of each toxin observed between the prey and the cephalopod predator indicates low conversion rates of these toxins. The depuration period was better described using an exponential decay model comprising a single compartment - the entire viscera. It is worth noting that since octopuses' excretion and depuration rates are low, the digestive gland is able to accumulate very high toxin concentrations for long periods of time. Therefore, the present study clearly shows that O. vulgaris is a high-potential vector of PSTs during and even after the occurrence of these toxic algal blooms.

  13. Uptake, transfer and elimination kinetics of paralytic shellfish toxins in common octopus (Octopus vulgaris).

    PubMed

    Lopes, Vanessa M; Baptista, Miguel; Repolho, Tiago; Rosa, Rui; Costa, Pedro Reis

    2014-01-01

    Marine phycotoxins derived from harmful algal blooms are known to be associated with mass mortalities in the higher trophic levels of marine food webs. Bivalve mollusks and planktivorous fish are the most studied vectors of marine phycotoxins. However, field surveys recently showed that cephalopod mollusks also constitute potential vectors of toxins. Thus, here we determine, for the first time, the time course of accumulation and depuration of paralytic shellfish toxins (PSTs) in the common octopus (Octopus vulgaris). Concomitantly, the underlying kinetics of toxin transfer between tissue compartments was also calculated. Naturally contaminated clams were used to orally expose the octopus to PSTs during 6 days. Afterwards, octopus specimens were fed with non-contaminated shellfish during 10 days of depuration period. Toxins reached the highest concentrations in the digestive gland surpassing the levels in the kidney by three orders of magnitude. PSTs were not detected in any other tissue analyzed. Net accumulation efficiencies of 42% for GTX5, 36% for dcSTX and 23% for C1+2 were calculated for the digestive gland. These compounds were the most abundant toxins in both digestive gland and the contaminated shellfish diet. The small differences in relative abundance of each toxin observed between the prey and the cephalopod predator indicates low conversion rates of these toxins. The depuration period was better described using an exponential decay model comprising a single compartment - the entire viscera. It is worth noting that since octopuses' excretion and depuration rates are low, the digestive gland is able to accumulate very high toxin concentrations for long periods of time. Therefore, the present study clearly shows that O. vulgaris is a high-potential vector of PSTs during and even after the occurrence of these toxic algal blooms. PMID:24316438

  14. Aggregata (Protozoa: Apicomplexa) infection in the common octopus Octopus vulgaris from the West Mediterranean Sea: The infection rates and possible effect of faunistic, environmental and ecological factors

    NASA Astrophysics Data System (ADS)

    Mayo-Hernández, E.; Barcala, E.; Berriatua, E.; García-Ayala, A.; Muñoz, P.

    2013-10-01

    Prevalence and distribution of the coccidian parasite Aggregata octopiana (Protozoa: Apicomplexa) in common octopus (Octopus vulgaris) in the Mediterranean Spanish coasts were studied. A total of 114 octopuses were sampled from 30 geographic sectors by trawl fleet, and whitish macroscopic oocysts typical of A. octopiana infection were recorded in 96% of octopuses in the digestive tract and mainly in intestine and spiral caecum. The univariate analysis showed that lesion extension varied according to specific octopus, environmental and faunistic variables. A subsequent multivariable analysis indicated that the risk of macroscopic lesions in the caecum was greater in males compared to females, in octopuses living in deeper compared to shallower waters and in hauls where the crustacean Pagurus excavatus was present. The study provides further evidence of the abundance of A. octopiana in octopus ecosystems urging for further studies to evaluate its health impact. The combined abundance of infected octopuses and P. excavatus merits attention.

  15. Arm coordination in octopus crawling involves unique motor control strategies.

    PubMed

    Levy, Guy; Flash, Tamar; Hochner, Binyamin

    2015-05-01

    To cope with the exceptional computational complexity that is involved in the control of its hyper-redundant arms [1], the octopus has adopted unique motor control strategies in which the central brain activates rather autonomous motor programs in the elaborated peripheral nervous system of the arms [2, 3]. How octopuses coordinate their eight long and flexible arms in locomotion is still unknown. Here, we present the first detailed kinematic analysis of octopus arm coordination in crawling. The results are surprising in several respects: (1) despite its bilaterally symmetrical body, the octopus can crawl in any direction relative to its body orientation; (2) body and crawling orientation are monotonically and independently controlled; and (3) contrasting known animal locomotion, octopus crawling lacks any apparent rhythmical patterns in limb coordination, suggesting a unique non-rhythmical output of the octopus central controller. We show that this uncommon maneuverability is derived from the radial symmetry of the arms around the body and the simple pushing-by-elongation mechanism by which the arms create the crawling thrust. These two together enable a mechanism whereby the central controller chooses in a moment-to-moment fashion which arms to recruit for pushing the body in an instantaneous direction. Our findings suggest that the soft molluscan body has affected in an embodied way [4, 5] the emergence of the adaptive motor behavior of the octopus.

  16. RETROSPECTIVE REVIEW OF MORTALITY IN GIANT PACIFIC OCTOPUS (ENTEROCTOPUS DOFLEINI).

    PubMed

    Seeley, Kathryn E; Clayton, Leigh A; Hadfield, Catherine A; Muth, Dillon; Mankowski, Joseph L; Kelly, Kathleen M

    2016-03-01

    The giant Pacific octopus (Enteroctopus dofleini) is a popular exhibit species in public display aquaria, but information on health and disease is limited. This retrospective review evaluates time in collection and describes antemortem clinical signs and pathology of giant Pacific octopuses in an aquarium setting. Between March 2004 and December 2013, there were 19 mortalities: eight males, 10 females, and one individual whose sex was not recorded. Average time spent in collection for all octopuses was 375 ± 173 days (males 351 ± 148 days, females 410 ± 196 days). Ten (52.6%) of the octopuses were sexually mature at the time of death, six (31.6%) were not sexually mature, and reproductive status could not be determined in three octopuses (15.8%). Minimal changes were noted on gross necropsy but branchitis was histologically evident in 14 octopuses, often in conjunction with amoeboid or flagellate parasites. Senescence, parasitism, and husbandry were all important contributors to mortality and should be considered when caring for captive octopuses.

  17. Allopatric speciation within a cryptic species complex of Australasian octopuses.

    PubMed

    Amor, Michael D; Norman, Mark D; Cameron, Hayley E; Strugnell, Jan M

    2014-01-01

    Despite extensive revisions over recent decades, the taxonomy of benthic octopuses (Family Octopodidae) remains in a considerable flux. Among groups of unresolved status is a species complex of morphologically similar shallow-water octopods from subtropical Australasia, including: Allopatric populations of Octopus tetricus on the eastern and western coasts of Australia, of which the Western Australian form is speculated to be a distinct or sub-species; and Octopus gibbsi from New Zealand, a proposed synonym of Australian forms. This study employed a combination of molecular and morphological techniques to resolve the taxonomic status of the 'tetricus complex'. Phylogenetic analyses (based on five mitochondrial genes: 12S rRNA, 16S rRNA, COI, COIII and Cytb) and Generalised Mixed Yule Coalescent (GMYC) analysis (based on COI, COIII and Cytb) distinguished eastern and Western Australian O. tetricus as distinct species, while O. gibbsi was found to be synonymous with the east Australian form (BS = >97, PP = 1; GMYC p = 0.01). Discrete morphological differences in mature male octopuses (based on sixteen morphological traits) provided further evidence of cryptic speciation between east (including New Zealand) and west coast populations; although females proved less useful in morphological distinction among members of the tetricus complex. In addition, phylogenetic analyses suggested populations of octopuses currently treated under the name Octopus vulgaris are paraphyletic; providing evidence of cryptic speciation among global populations of O. vulgaris, the most commercially valuable octopus species worldwide.

  18. Arm coordination in octopus crawling involves unique motor control strategies.

    PubMed

    Levy, Guy; Flash, Tamar; Hochner, Binyamin

    2015-05-01

    To cope with the exceptional computational complexity that is involved in the control of its hyper-redundant arms [1], the octopus has adopted unique motor control strategies in which the central brain activates rather autonomous motor programs in the elaborated peripheral nervous system of the arms [2, 3]. How octopuses coordinate their eight long and flexible arms in locomotion is still unknown. Here, we present the first detailed kinematic analysis of octopus arm coordination in crawling. The results are surprising in several respects: (1) despite its bilaterally symmetrical body, the octopus can crawl in any direction relative to its body orientation; (2) body and crawling orientation are monotonically and independently controlled; and (3) contrasting known animal locomotion, octopus crawling lacks any apparent rhythmical patterns in limb coordination, suggesting a unique non-rhythmical output of the octopus central controller. We show that this uncommon maneuverability is derived from the radial symmetry of the arms around the body and the simple pushing-by-elongation mechanism by which the arms create the crawling thrust. These two together enable a mechanism whereby the central controller chooses in a moment-to-moment fashion which arms to recruit for pushing the body in an instantaneous direction. Our findings suggest that the soft molluscan body has affected in an embodied way [4, 5] the emergence of the adaptive motor behavior of the octopus. PMID:25891406

  19. Allopatric speciation within a cryptic species complex of Australasian octopuses.

    PubMed

    Amor, Michael D; Norman, Mark D; Cameron, Hayley E; Strugnell, Jan M

    2014-01-01

    Despite extensive revisions over recent decades, the taxonomy of benthic octopuses (Family Octopodidae) remains in a considerable flux. Among groups of unresolved status is a species complex of morphologically similar shallow-water octopods from subtropical Australasia, including: Allopatric populations of Octopus tetricus on the eastern and western coasts of Australia, of which the Western Australian form is speculated to be a distinct or sub-species; and Octopus gibbsi from New Zealand, a proposed synonym of Australian forms. This study employed a combination of molecular and morphological techniques to resolve the taxonomic status of the 'tetricus complex'. Phylogenetic analyses (based on five mitochondrial genes: 12S rRNA, 16S rRNA, COI, COIII and Cytb) and Generalised Mixed Yule Coalescent (GMYC) analysis (based on COI, COIII and Cytb) distinguished eastern and Western Australian O. tetricus as distinct species, while O. gibbsi was found to be synonymous with the east Australian form (BS = >97, PP = 1; GMYC p = 0.01). Discrete morphological differences in mature male octopuses (based on sixteen morphological traits) provided further evidence of cryptic speciation between east (including New Zealand) and west coast populations; although females proved less useful in morphological distinction among members of the tetricus complex. In addition, phylogenetic analyses suggested populations of octopuses currently treated under the name Octopus vulgaris are paraphyletic; providing evidence of cryptic speciation among global populations of O. vulgaris, the most commercially valuable octopus species worldwide. PMID:24964133

  20. RETROSPECTIVE REVIEW OF MORTALITY IN GIANT PACIFIC OCTOPUS (ENTEROCTOPUS DOFLEINI).

    PubMed

    Seeley, Kathryn E; Clayton, Leigh A; Hadfield, Catherine A; Muth, Dillon; Mankowski, Joseph L; Kelly, Kathleen M

    2016-03-01

    The giant Pacific octopus (Enteroctopus dofleini) is a popular exhibit species in public display aquaria, but information on health and disease is limited. This retrospective review evaluates time in collection and describes antemortem clinical signs and pathology of giant Pacific octopuses in an aquarium setting. Between March 2004 and December 2013, there were 19 mortalities: eight males, 10 females, and one individual whose sex was not recorded. Average time spent in collection for all octopuses was 375 ± 173 days (males 351 ± 148 days, females 410 ± 196 days). Ten (52.6%) of the octopuses were sexually mature at the time of death, six (31.6%) were not sexually mature, and reproductive status could not be determined in three octopuses (15.8%). Minimal changes were noted on gross necropsy but branchitis was histologically evident in 14 octopuses, often in conjunction with amoeboid or flagellate parasites. Senescence, parasitism, and husbandry were all important contributors to mortality and should be considered when caring for captive octopuses. PMID:27010286

  1. Allopatric Speciation within a Cryptic Species Complex of Australasian Octopuses

    PubMed Central

    Amor, Michael D.; Norman, Mark D.; Cameron, Hayley E.; Strugnell, Jan M.

    2014-01-01

    Despite extensive revisions over recent decades, the taxonomy of benthic octopuses (Family Octopodidae) remains in a considerable flux. Among groups of unresolved status is a species complex of morphologically similar shallow-water octopods from subtropical Australasia, including: Allopatric populations of Octopus tetricus on the eastern and western coasts of Australia, of which the Western Australian form is speculated to be a distinct or sub-species; and Octopus gibbsi from New Zealand, a proposed synonym of Australian forms. This study employed a combination of molecular and morphological techniques to resolve the taxonomic status of the ‘tetricus complex’. Phylogenetic analyses (based on five mitochondrial genes: 12S rRNA, 16S rRNA, COI, COIII and Cytb) and Generalised Mixed Yule Coalescent (GMYC) analysis (based on COI, COIII and Cytb) distinguished eastern and Western Australian O. tetricus as distinct species, while O. gibbsi was found to be synonymous with the east Australian form (BS = >97, PP = 1; GMYC p = 0.01). Discrete morphological differences in mature male octopuses (based on sixteen morphological traits) provided further evidence of cryptic speciation between east (including New Zealand) and west coast populations; although females proved less useful in morphological distinction among members of the tetricus complex. In addition, phylogenetic analyses suggested populations of octopuses currently treated under the name Octopus vulgaris are paraphyletic; providing evidence of cryptic speciation among global populations of O. vulgaris, the most commercially valuable octopus species worldwide. PMID:24964133

  2. [Effect of freezing and cooking on the texture and electrophoretic pattern of the proteins of octopus arms (Octopus vulgaris)].

    PubMed

    Reyes, Genara; Nirchio, Mauro; Bello, Rafael; Borderías, Javier

    2014-09-01

    Texture is the most valuable feature in cephalopods. Factors that mainly affect the texture of octopus are: freezing, scalding and cooking. The aim of this study was to assess the effect of freezing, scalding and length of cooking time on the texture and electrophoretic pattern of proteins of octopus arms. Octopuses were trapped near Margarita Island and carried with ice to the laboratory where they were packed and subjected to: a) freezing at -27 degrees C or at -20 degrees C b) scalding c) cooking for 25 min, 35 min or 45 min. Shear force was determined by Kramer cell on strips of octopus arms. SDS-PAGE was done according to the Laemmli method with 12% polyacrilamide gels. A sensory evaluation of the preference of texture was carried out using a hedonic scale of 7-points and a non-trained panel. Octopus texture was not affected by freezing temperature or scalding. Frozen octopus was softer after cooking than fresh. The longer the cooking time was, the softer the octopus was. Myosin heavy chain (MHC) was not significantly affected by scalding or cooking; however large aggregates heavier than MHC, new bands and loss of resolution of the bands appeared. Myosin and paramyosin bands were more affected by freezing prior to cooking. PMID:26137796

  3. [Effect of freezing and cooking on the texture and electrophoretic pattern of the proteins of octopus arms (Octopus vulgaris)].

    PubMed

    Reyes, Genara; Nirchio, Mauro; Bello, Rafael; Borderías, Javier

    2014-09-01

    Texture is the most valuable feature in cephalopods. Factors that mainly affect the texture of octopus are: freezing, scalding and cooking. The aim of this study was to assess the effect of freezing, scalding and length of cooking time on the texture and electrophoretic pattern of proteins of octopus arms. Octopuses were trapped near Margarita Island and carried with ice to the laboratory where they were packed and subjected to: a) freezing at -27 degrees C or at -20 degrees C b) scalding c) cooking for 25 min, 35 min or 45 min. Shear force was determined by Kramer cell on strips of octopus arms. SDS-PAGE was done according to the Laemmli method with 12% polyacrilamide gels. A sensory evaluation of the preference of texture was carried out using a hedonic scale of 7-points and a non-trained panel. Octopus texture was not affected by freezing temperature or scalding. Frozen octopus was softer after cooking than fresh. The longer the cooking time was, the softer the octopus was. Myosin heavy chain (MHC) was not significantly affected by scalding or cooking; however large aggregates heavier than MHC, new bands and loss of resolution of the bands appeared. Myosin and paramyosin bands were more affected by freezing prior to cooking.

  4. Phosphoglycopeptide, a major constituent of the spermatophoric plasma of the octopus (Octopus dofleini martini).

    PubMed

    Brooks, D E; Tate, M E; Mann, T; Martin, A W

    1981-11-01

    A phosphoglycopeptide, accounting for approximately 90% of the characteristically high content of acid-soluble organically-bound phosphorus in the octopus spermatophoric plasma (4 mg P/ml), was identified. Electrophoretic and chromatographic purification, followed by chemical and enzymic hydrolysis, yielded D-galactose phosphate as a degradation product. The galactose and peptide moieties of the compound were linked via a phosphoryl rather than a glycosidic linkage but the peptide was devoid of aromatic amino acids. PMID:7299753

  5. Invertebrate neurobiology: visual direction of arm movements in an octopus.

    PubMed

    Niven, Jeremy E

    2011-03-22

    An operant task in which octopuses learn to locate food by a visual cue in a three-choice maze shows that they are capable of integrating visual and mechanosensory information to direct their arm movements to a goal.

  6. Amino and fatty acid dynamics of octopus (Octopus vulgaris) early life stages under ocean warming.

    PubMed

    Lopes, Vanessa M; Faleiro, Filipa; Baptista, Miguel; Pimentel, Marta S; Paula, José R; Couto, Ana; Bandarra, Narcisa; Anacleto, Patrícia; Marques, António; Rosa, Rui

    2016-01-01

    The oceans are becoming warmer, and the higher temperatures are expected to have a major impact on marine life at different levels of biological organization, especially at the most vulnerable early life stages. Thus, we hypothesize that the future warmer scenarios (here +3 °C) will affect the biochemical composition (amino acid - AA, and fatty acid-FA) of octopod (Octopus vulgaris) embryos and recently-hatched pelagic paralarvae. The main essential amino acids found in octopus embryos were arginine, leucine and lysine; while aspartic and glutamic acids, and taurine were the main non-essential amino acids. Palmitic, eicosapentaenoic and docosahexaenoic acids were the main FAs found in octopus tissues. Relevant ontogenetic changes were observed, namely a steep decrease in the content of many AAs, and a selective retention of FAs, thus evidencing the protein-based metabolism of these cephalopods. Temperature per si did not elicit significant changes in the overall FA composition, but was responsible for a significant decrease in the content of several AAs, indicating increased embryonic consumption.

  7. Amino and fatty acid dynamics of octopus (Octopus vulgaris) early life stages under ocean warming.

    PubMed

    Lopes, Vanessa M; Faleiro, Filipa; Baptista, Miguel; Pimentel, Marta S; Paula, José R; Couto, Ana; Bandarra, Narcisa; Anacleto, Patrícia; Marques, António; Rosa, Rui

    2016-01-01

    The oceans are becoming warmer, and the higher temperatures are expected to have a major impact on marine life at different levels of biological organization, especially at the most vulnerable early life stages. Thus, we hypothesize that the future warmer scenarios (here +3 °C) will affect the biochemical composition (amino acid - AA, and fatty acid-FA) of octopod (Octopus vulgaris) embryos and recently-hatched pelagic paralarvae. The main essential amino acids found in octopus embryos were arginine, leucine and lysine; while aspartic and glutamic acids, and taurine were the main non-essential amino acids. Palmitic, eicosapentaenoic and docosahexaenoic acids were the main FAs found in octopus tissues. Relevant ontogenetic changes were observed, namely a steep decrease in the content of many AAs, and a selective retention of FAs, thus evidencing the protein-based metabolism of these cephalopods. Temperature per si did not elicit significant changes in the overall FA composition, but was responsible for a significant decrease in the content of several AAs, indicating increased embryonic consumption. PMID:26724195

  8. Multiple object redshift determinations in clusters of galaxies using OCTOPUS

    NASA Astrophysics Data System (ADS)

    Mazure, A.; Proust, D.; Sodre, L.; Lund, G.; Capelato, H.

    1987-03-01

    The ESO multiobject facility, Octopus, was used to observe a sample of galaxy clusters such as SC2008-565 in an attempt to collect a large set of individual radial velocities. A dispersion of 114 A/mm was used, providing spectral coverage from 3800 to 5180 A. Octopus was found to be a well-adapted instrument for the rapid and simultaneous determination of redshifts in cataloged galaxy clusters.

  9. Multiple object redshift determinations in clusters of galaxies using OCTOPUS

    NASA Astrophysics Data System (ADS)

    Mazure, A.; Proust, D.; Sodre, L.; Capelato, H. V.; Lund, G.

    1988-04-01

    The ESO multiobject facility, Octopus, was used to observe a sample of galaxy clusters such as SC2008-565 in an attempt to collect a large set of individual radial velocities. A dispersion of 114 A/mm was used, providing spectral coverage from 3800 to 5180 A. Octopus was found to be a well-adapted instrument for the rapid and simultaneous determination of redshifts in cataloged galaxy clusters.

  10. The morphology and adhesion mechanism of Octopus vulgaris suckers.

    PubMed

    Tramacere, Francesca; Beccai, Lucia; Kuba, Michael; Gozzi, Alessandro; Bifone, Angelo; Mazzolai, Barbara

    2013-01-01

    The octopus sucker represents a fascinating natural system performing adhesion on different terrains and substrates. Octopuses use suckers to anchor the body to the substrate or to grasp, investigate and manipulate objects, just to mention a few of their functions. Our study focuses on the morphology and adhesion mechanism of suckers in Octopus vulgaris. We use three different techniques (MRI, ultrasonography, and histology) and a 3D reconstruction approach to contribute knowledge on both morphology and functionality of the sucker structure in O. vulgaris. The results of our investigation are two-fold. First, we observe some morphological differences with respect to the octopus species previously studied (i.e., Octopus joubini, Octopus maya, Octopus bimaculoides/bimaculatus and Eledone cirrosa). In particular, in O. vulgaris the acetabular chamber, that is a hollow spherical cavity in other octopuses, shows an ellipsoidal cavity which roof has an important protuberance with surface roughness. Second, based on our findings, we propose a hypothesis on the sucker adhesion mechanism in O. vulgaris. We hypothesize that the process of continuous adhesion is achieved by sealing the orifice between acetabulum and infundibulum portions via the acetabular protuberance. We suggest this to take place while the infundibular part achieves a completely flat shape; and, by sustaining adhesion through preservation of sucker configuration. In vivo ultrasonographic recordings support our proposed adhesion model by showing the sucker in action. Such an underlying physical mechanism offers innovative potential cues for developing bioinspired artificial adhesion systems. Furthermore, we think that it could possibly represent a useful approach in order to investigate any potential difference in the ecology and in the performance of adhesion by different species.

  11. The morphology and adhesion mechanism of Octopus vulgaris suckers.

    PubMed

    Tramacere, Francesca; Beccai, Lucia; Kuba, Michael; Gozzi, Alessandro; Bifone, Angelo; Mazzolai, Barbara

    2013-01-01

    The octopus sucker represents a fascinating natural system performing adhesion on different terrains and substrates. Octopuses use suckers to anchor the body to the substrate or to grasp, investigate and manipulate objects, just to mention a few of their functions. Our study focuses on the morphology and adhesion mechanism of suckers in Octopus vulgaris. We use three different techniques (MRI, ultrasonography, and histology) and a 3D reconstruction approach to contribute knowledge on both morphology and functionality of the sucker structure in O. vulgaris. The results of our investigation are two-fold. First, we observe some morphological differences with respect to the octopus species previously studied (i.e., Octopus joubini, Octopus maya, Octopus bimaculoides/bimaculatus and Eledone cirrosa). In particular, in O. vulgaris the acetabular chamber, that is a hollow spherical cavity in other octopuses, shows an ellipsoidal cavity which roof has an important protuberance with surface roughness. Second, based on our findings, we propose a hypothesis on the sucker adhesion mechanism in O. vulgaris. We hypothesize that the process of continuous adhesion is achieved by sealing the orifice between acetabulum and infundibulum portions via the acetabular protuberance. We suggest this to take place while the infundibular part achieves a completely flat shape; and, by sustaining adhesion through preservation of sucker configuration. In vivo ultrasonographic recordings support our proposed adhesion model by showing the sucker in action. Such an underlying physical mechanism offers innovative potential cues for developing bioinspired artificial adhesion systems. Furthermore, we think that it could possibly represent a useful approach in order to investigate any potential difference in the ecology and in the performance of adhesion by different species. PMID:23750233

  12. The Morphology and Adhesion Mechanism of Octopus vulgaris Suckers

    PubMed Central

    Tramacere, Francesca; Beccai, Lucia; Kuba, Michael; Gozzi, Alessandro; Bifone, Angelo; Mazzolai, Barbara

    2013-01-01

    The octopus sucker represents a fascinating natural system performing adhesion on different terrains and substrates. Octopuses use suckers to anchor the body to the substrate or to grasp, investigate and manipulate objects, just to mention a few of their functions. Our study focuses on the morphology and adhesion mechanism of suckers in Octopus vulgaris. We use three different techniques (MRI, ultrasonography, and histology) and a 3D reconstruction approach to contribute knowledge on both morphology and functionality of the sucker structure in O. vulgaris. The results of our investigation are two-fold. First, we observe some morphological differences with respect to the octopus species previously studied (i.e., Octopus joubini, Octopus maya, Octopus bimaculoides/bimaculatus and Eledone cirrosa). In particular, in O. vulgaris the acetabular chamber, that is a hollow spherical cavity in other octopuses, shows an ellipsoidal cavity which roof has an important protuberance with surface roughness. Second, based on our findings, we propose a hypothesis on the sucker adhesion mechanism in O. vulgaris. We hypothesize that the process of continuous adhesion is achieved by sealing the orifice between acetabulum and infundibulum portions via the acetabular protuberance. We suggest this to take place while the infundibular part achieves a completely flat shape; and, by sustaining adhesion through preservation of sucker configuration. In vivo ultrasonographic recordings support our proposed adhesion model by showing the sucker in action. Such an underlying physical mechanism offers innovative potential cues for developing bioinspired artificial adhesion systems. Furthermore, we think that it could possibly represent a useful approach in order to investigate any potential difference in the ecology and in the performance of adhesion by different species. PMID:23750233

  13. Pull or Push? Octopuses Solve a Puzzle Problem.

    PubMed

    Richter, Jonas N; Hochner, Binyamin; Kuba, Michael J

    2016-01-01

    Octopuses have large brains and exhibit complex behaviors, but relatively little is known about their cognitive abilities. Here we present data from a five-level learning and problem-solving experiment. Seven octopuses (Octopus vulgaris) were first trained to open an L shaped container to retrieve food (level 0). After learning the initial task all animals followed the same experimental protocol, first they had to retrieve this L shaped container, presented at the same orientation, through a tight fitting hole in a clear Perspex partition (level 1). This required the octopuses to perform both pull and release or push actions. After reaching criterion the animals advanced to the next stage of the test, which would be a different consistent orientation of the object (level 2) at the start of the trial, an opaque barrier (level 3) or a random orientation of the object (level 4). All octopuses were successful in reaching criterion in all levels of the task. At the onset of each new level the performance of the animals dropped, shown as an increase in working times. However, they adapted quickly so that overall working times were not significantly different between levels. Our findings indicate that octopuses show behavioral flexibility by quickly adapting to a change in a task. This can be compared to tests in other species where subjects had to conduct actions comprised of a set of motor actions that cannot be understood by a simple learning rule alone.

  14. Analyzing octopus movements using three-dimensional reconstruction.

    PubMed

    Yekutieli, Yoram; Mitelman, Rea; Hochner, Binyamin; Flash, Tamar

    2007-09-01

    Octopus arms, as well as other muscular hydrostats, are characterized by a very large number of degrees of freedom and a rich motion repertoire. Over the years, several attempts have been made to elucidate the interplay between the biomechanics of these organs and their control systems. Recent developments in electrophysiological recordings from both the arms and brains of behaving octopuses mark significant progress in this direction. The next stage is relating these recordings to the octopus arm movements, which requires an accurate and reliable method of movement description and analysis. Here we describe a semiautomatic computerized system for 3D reconstruction of an octopus arm during motion. It consists of two digital video cameras and a PC computer running custom-made software. The system overcomes the difficulty of extracting the motion of smooth, nonrigid objects in poor viewing conditions. Some of the trouble is explained by the problem of light refraction in recording underwater motion. Here we use both experiments and simulations to analyze the refraction problem and show that accurate reconstruction is possible. We have used this system successfully to reconstruct different types of octopus arm movements, such as reaching and bend initiation movements. Our system is noninvasive and does not require attaching any artificial markers to the octopus arm. It may therefore be of more general use in reconstructing other nonrigid, elongated objects in motion.

  15. Pull or Push? Octopuses Solve a Puzzle Problem.

    PubMed

    Richter, Jonas N; Hochner, Binyamin; Kuba, Michael J

    2016-01-01

    Octopuses have large brains and exhibit complex behaviors, but relatively little is known about their cognitive abilities. Here we present data from a five-level learning and problem-solving experiment. Seven octopuses (Octopus vulgaris) were first trained to open an L shaped container to retrieve food (level 0). After learning the initial task all animals followed the same experimental protocol, first they had to retrieve this L shaped container, presented at the same orientation, through a tight fitting hole in a clear Perspex partition (level 1). This required the octopuses to perform both pull and release or push actions. After reaching criterion the animals advanced to the next stage of the test, which would be a different consistent orientation of the object (level 2) at the start of the trial, an opaque barrier (level 3) or a random orientation of the object (level 4). All octopuses were successful in reaching criterion in all levels of the task. At the onset of each new level the performance of the animals dropped, shown as an increase in working times. However, they adapted quickly so that overall working times were not significantly different between levels. Our findings indicate that octopuses show behavioral flexibility by quickly adapting to a change in a task. This can be compared to tests in other species where subjects had to conduct actions comprised of a set of motor actions that cannot be understood by a simple learning rule alone. PMID:27003439

  16. Pull or Push? Octopuses Solve a Puzzle Problem

    PubMed Central

    Richter, Jonas N.; Hochner, Binyamin; Kuba, Michael J.

    2016-01-01

    Octopuses have large brains and exhibit complex behaviors, but relatively little is known about their cognitive abilities. Here we present data from a five-level learning and problem-solving experiment. Seven octopuses (Octopus vulgaris) were first trained to open an L shaped container to retrieve food (level 0). After learning the initial task all animals followed the same experimental protocol, first they had to retrieve this L shaped container, presented at the same orientation, through a tight fitting hole in a clear Perspex partition (level 1). This required the octopuses to perform both pull and release or push actions. After reaching criterion the animals advanced to the next stage of the test, which would be a different consistent orientation of the object (level 2) at the start of the trial, an opaque barrier (level 3) or a random orientation of the object (level 4). All octopuses were successful in reaching criterion in all levels of the task. At the onset of each new level the performance of the animals dropped, shown as an increase in working times. However, they adapted quickly so that overall working times were not significantly different between levels. Our findings indicate that octopuses show behavioral flexibility by quickly adapting to a change in a task. This can be compared to tests in other species where subjects had to conduct actions comprised of a set of motor actions that cannot be understood by a simple learning rule alone. PMID:27003439

  17. How do octopuses use their arms?

    PubMed

    Mather, J A

    1998-09-01

    A taxonomy of the movement patterns of the 8 flexible arms of octopuses is constructed. Components consist of movements of the arm itself, the ventral suckers and their stalks, as well as the relative position of arms and the skin web between them. Within 1 arm, combinations of components result in a variety of behaviors. At the level of all arms, 1 group of behaviors is described as postures, on the basis of the spread of all arms and the web to make a 2-dimensional surface whose position differs in the 3rd dimension. Another group of arm behaviors is actions, more or less coordinated and involving several to all arms. Arm control appears to be based on radial symmetry, relative equipotentiality of all arms, relative independence of each arm, and separability of components within the arm. The types and coordination of arm behaviors are discussed with relationship to biomechanical limits, muscle structures, and neuronal programming.

  18. Developmental and physiological challenges of octopus (Octopus vulgaris) early life stages under ocean warming.

    PubMed

    Repolho, Tiago; Baptista, Miguel; Pimentel, Marta S; Dionísio, Gisela; Trübenbach, Katja; Lopes, Vanessa M; Lopes, Ana Rita; Calado, Ricardo; Diniz, Mário; Rosa, Rui

    2014-01-01

    The ability to understand and predict the effects of ocean warming (under realistic scenarios) on marine biota is of paramount importance, especially at the most vulnerable early life stages. Here we investigated the impact of predicted environmental warming (+3 °C) on the development, metabolism, heat shock response and antioxidant defense mechanisms of the early stages of the common octopus, Octopus vulgaris. As expected, warming shortened embryonic developmental time by 13 days, from 38 days at 18 °C to 25 days at 21 °C. Concomitantly, survival decreased significantly (~29.9 %). Size at hatching varied inversely with temperature, and the percentage of smaller premature paralarvae increased drastically, from 0 % at 18 °C to 17.8 % at 21 °C. The metabolic costs of the transition from an encapsulated embryo to a free planktonic form increased significantly with warming, and HSP70 concentrations and glutathione S-transferase activity levels were significantly magnified from late embryonic to paralarval stages. Yet, despite the presence of effective antioxidant defense mechanisms, ocean warming led to an augmentation of malondialdehyde levels (an indicative of enhanced ROS action), a process considered to be one of the most frequent cellular injury mechanisms. Thus, the present study provides clues about how the magnitude and rate of ocean warming will challenge the buffering capacities of octopus embryos and hatchlings' physiology. The prediction and understanding of the biochemical and physiological responses to warmer temperatures (under realistic scenarios) is crucial for the management of highly commercial and ecologically important species, such as O. vulgaris. PMID:24100467

  19. Developmental and physiological challenges of octopus (Octopus vulgaris) early life stages under ocean warming.

    PubMed

    Repolho, Tiago; Baptista, Miguel; Pimentel, Marta S; Dionísio, Gisela; Trübenbach, Katja; Lopes, Vanessa M; Lopes, Ana Rita; Calado, Ricardo; Diniz, Mário; Rosa, Rui

    2014-01-01

    The ability to understand and predict the effects of ocean warming (under realistic scenarios) on marine biota is of paramount importance, especially at the most vulnerable early life stages. Here we investigated the impact of predicted environmental warming (+3 °C) on the development, metabolism, heat shock response and antioxidant defense mechanisms of the early stages of the common octopus, Octopus vulgaris. As expected, warming shortened embryonic developmental time by 13 days, from 38 days at 18 °C to 25 days at 21 °C. Concomitantly, survival decreased significantly (~29.9 %). Size at hatching varied inversely with temperature, and the percentage of smaller premature paralarvae increased drastically, from 0 % at 18 °C to 17.8 % at 21 °C. The metabolic costs of the transition from an encapsulated embryo to a free planktonic form increased significantly with warming, and HSP70 concentrations and glutathione S-transferase activity levels were significantly magnified from late embryonic to paralarval stages. Yet, despite the presence of effective antioxidant defense mechanisms, ocean warming led to an augmentation of malondialdehyde levels (an indicative of enhanced ROS action), a process considered to be one of the most frequent cellular injury mechanisms. Thus, the present study provides clues about how the magnitude and rate of ocean warming will challenge the buffering capacities of octopus embryos and hatchlings' physiology. The prediction and understanding of the biochemical and physiological responses to warmer temperatures (under realistic scenarios) is crucial for the management of highly commercial and ecologically important species, such as O. vulgaris.

  20. Molecular and functional characterization of a novel gonadotropin-releasing-hormone receptor isolated from the common octopus (Octopus vulgaris).

    PubMed

    Kanda, Atsuhiro; Takahashi, Toshio; Satake, Honoo; Minakata, Hiroyuki

    2006-04-01

    GnRH (gonadotropin-releasing hormone) plays a pivotal role in the regulation of reproduction in vertebrates through interaction with a specific receptor. Previously, we isolated a GnRH homologue, oct-GnRH, from the common octopus (Octopus vulgaris). In the present study, we have identified a GnRH receptor (oct-GnRHR) specific for oct-GnRH from Octopus brain. Oct-GnRHR includes domains and motifs typical of vertebrate GnRH receptors. The intron-inserted positions are conserved between oct-GnRHR and the chordate GnRHR genes. The oct-GnRHR expressed in Xenopus (South African clawed frog) oocytes was responsive to oct-GnRH, but not to any other HPLC fractions of the Octopus brain extract. These results show that oct-GnRHR is an authentic receptor for oct-GnRH. Southern blotting of reverse-transcription PCR products revealed that the oct-GnRHR mRNA was widely distributed in the central and peripheral nervous systems and in several peripheral tissues. In situ hybridization showed that oct-GnRHR mRNA was expressed in some regions involved in autonomic functions, feeding, memory and movement. Oct-GnRH was shown to induce steroidogenesis of testosterone, progesterone and 17beta-oestradiol in Octopus ovary and testis, where oct-GnRHR was abundantly expressed. These results suggest that oct-GnRH, like its vertebrate counterparts, acts as a multifunctional neurotransmitter, neuromodulator and hormone-like factor, both in Octopus central nervous system and peripheral tissues, and that both structure and functions of the GnRH family are, at least partially, evolutionarily conserved between octopuses and chordates.

  1. Fecal hormones measured within giant Pacific octopuses Enteroctopus dofleini.

    PubMed

    Larson, Shawn E; Anderson, Roland C

    2010-09-01

    The captive husbandry of giant Pacific octopuses Enteroctopus dofleini is well understood, but their endocrine signatures are not well documented. The major vertebrate reproductive hormones--estrogen, progesterone, and testosterone--and the stress-related hormone corticosterone are relatively well known for many vertebrate species. However, few studies on these hormones within invertebrates have been conducted. Our hypothesis was that endocrine signatures within octopuses are similar to those found within vertebrates in response to reproductive activity and stress. Using standard immunoassay techniques, we measured fecal steroids within fecal samples collected from five female and three male giant Pacific octopuses housed at the Seattle Aquarium. The mean estrogen level ranged from 3.67 to 99.39 ng/g of feces, progesterone ranged from 44.35 to 231.71 ng/g feces, testosterone ranged from 9.30 to 18.18 ng/g feces, and corticosterone ranged from 10.91 to 22.14 ng/g feces. The results suggest that octopus fecal hormones are similar to those in vertebrates and may be useful in measuring ovarian activity and stress within captive female giant Pacific octopuses.

  2. Advances in the laboratory culture of octopuses for biomedical research.

    PubMed

    Hanlon, R T; Forsythe, J W

    1985-02-01

    Five species of Octopus were cultured in pilot, large-scale 2,600 liter circulating seawater systems. Improvements in system design, water management and culture methodology were described. These five species all produced large eggs and correspondingly large hatchlings that had no planktonic or larval stage and thus were easier to culture. Octopuses grew well only when fed live marine crustaceans, fishes and other molluscs. Growth occurred as a 4-7% increase in body weight per day during the early exponential growth phase and 2-4% during the latter 1/2 to 3/4 of the life cycle, which ranged from 6-15 months depending upon species. All species reproduced in captivity. Survival was 70-80% when octopuses were reared in individual containers, but in group culture survival dropped to as low as 40% by the adult stage. Causes of mortality were species-specific and included hatchling abnormalities, escapes, aggression, cannibalism, disease, senescence and laboratory accidents. Octopus bimaculoides showed superior qualities for laboratory culture. The future potential of providing American scientists with laboratory-cultured octopuses was discussed along with their uses in biomedical research.

  3. Fecal hormones measured within giant Pacific octopuses Enteroctopus dofleini.

    PubMed

    Larson, Shawn E; Anderson, Roland C

    2010-09-01

    The captive husbandry of giant Pacific octopuses Enteroctopus dofleini is well understood, but their endocrine signatures are not well documented. The major vertebrate reproductive hormones--estrogen, progesterone, and testosterone--and the stress-related hormone corticosterone are relatively well known for many vertebrate species. However, few studies on these hormones within invertebrates have been conducted. Our hypothesis was that endocrine signatures within octopuses are similar to those found within vertebrates in response to reproductive activity and stress. Using standard immunoassay techniques, we measured fecal steroids within fecal samples collected from five female and three male giant Pacific octopuses housed at the Seattle Aquarium. The mean estrogen level ranged from 3.67 to 99.39 ng/g of feces, progesterone ranged from 44.35 to 231.71 ng/g feces, testosterone ranged from 9.30 to 18.18 ng/g feces, and corticosterone ranged from 10.91 to 22.14 ng/g feces. The results suggest that octopus fecal hormones are similar to those in vertebrates and may be useful in measuring ovarian activity and stress within captive female giant Pacific octopuses. PMID:21192544

  4. Advances in the laboratory culture of octopuses for biomedical research.

    PubMed

    Hanlon, R T; Forsythe, J W

    1985-02-01

    Five species of Octopus were cultured in pilot, large-scale 2,600 liter circulating seawater systems. Improvements in system design, water management and culture methodology were described. These five species all produced large eggs and correspondingly large hatchlings that had no planktonic or larval stage and thus were easier to culture. Octopuses grew well only when fed live marine crustaceans, fishes and other molluscs. Growth occurred as a 4-7% increase in body weight per day during the early exponential growth phase and 2-4% during the latter 1/2 to 3/4 of the life cycle, which ranged from 6-15 months depending upon species. All species reproduced in captivity. Survival was 70-80% when octopuses were reared in individual containers, but in group culture survival dropped to as low as 40% by the adult stage. Causes of mortality were species-specific and included hatchling abnormalities, escapes, aggression, cannibalism, disease, senescence and laboratory accidents. Octopus bimaculoides showed superior qualities for laboratory culture. The future potential of providing American scientists with laboratory-cultured octopuses was discussed along with their uses in biomedical research. PMID:3981958

  5. Purification, cloning, and immunological characterization of arginine kinase, a novel allergen of Octopus fangsiao.

    PubMed

    Shen, Hai-Wang; Cao, Min-Jie; Cai, Qiu-Feng; Ruan, Mi-Mi; Mao, Hai-Yan; Su, Wen-Jin; Liu, Guang-Ming

    2012-03-01

    Arginine kinase (AK) is an important enzyme participating in energy metabolism in invertebrates, but, to date, there have been no reports that AK from octopus is an allergen. In this study, octopus AK was purified, and its molecular biological, immunological, and physicochemical characterizations were analyzed. The results showed that octopus AK was purified and confirmed by mass spectrometry for the first time, and its molecular mass was 38 kDa. The full-length gene sequence of octopus AK encompassed 1209 bp and was predicted to encode a protein with 348 amino acid residues. The homology of octopus AK and crustacean AK was about 54%, but the similarity between their three-dimensional structures was high. Octopus AK could react with mouse anti-shrimp AK and rabbit anti-crab AK polyclonal antibody singly. Octopus AK could also react with specific IgE of the sera from octopus-allergic patients effectively, whereas crab AK could inhibit the reaction between them. Finally, the IgE-binding activity of octopus AK could be reduced in the processes of thermal or acid-alkali treatment. In summary, AK was identified as a novel allergen in octopus, which had a sensitizing ability similar to that of crustacean AK. This is significant in allergy diagnosis and the treatment of octopus-allergic disorders.

  6. Laboratory maintenance, breeding, rearing, and biomedical research potential of the Yucatan octopus (Octopus maya).

    PubMed

    Van Heukelem, W F

    1977-10-01

    Eggs of the Yucatan octopus, Octopus maya, were collected at Campeche, Mexico, transported to Hawaii, and incubated in glass funnels. Benthic juveniles hatched from the large (17-mm) eggs and were reared on a variety of live and frozen foods. As many as 200 animals were reared for the first month in a 20-liter aquarium. No disease or parasite problems were encountered and nearly all well-fed juveniles survived to sexual maturity. The species was reared through four generations in the laboratory. Animals weighed 0.1 g at hatching and within 8.5 months attained an average weight of 3231 g. Mating was promiscuous and sperm were stored in the oviducts until spawning. Spawning occurred at 8-9 months of age. Up to 5,000 eggs were laid by large females and nearly 100% of fertilized eggs developed to hatching. Females brooded eggs during the 45-day period of development but artificial was as successful as natural incubation by the mother. Pos-reproductive senescent decline of both males and females was rapid and average life span was 300 days from hatching. Areas of biomedical research in which O maya could be a useful model were suggested and included neurobiology, comparative psychology, ontogeny of behavior, immunology, endocrinology, and studies of aging. PMID:592733

  7. An analog VLSI chip emulating polarization vision of Octopus retina.

    PubMed

    Momeni, Massoud; Titus, Albert H

    2006-01-01

    Biological systems provide a wealth of information which form the basis for human-made artificial systems. In this work, the visual system of Octopus is investigated and its polarization sensitivity mimicked. While in actual Octopus retina, polarization vision is mainly based on the orthogonal arrangement of its photoreceptors, our implementation uses a birefringent micropolarizer made of YVO4 and mounted on a CMOS chip with neuromorphic circuitry to process linearly polarized light. Arranged in an 8 x 5 array with two photodiodes per pixel, each consuming typically 10 microW, this circuitry mimics both the functionality of individual Octopus retina cells by computing the state of polarization and the interconnection of these cells through a bias-controllable resistive network.

  8. Biorobotic investigation on the muscle structure of an octopus tentacle.

    PubMed

    Mazzolai, Barbara; Laschi, Cecilia; Cianchetti, Matteo; Patanè, Francesco; Bassi-Luciani, Lorenzo; Izzo, Ivano; Dario, Paolo

    2007-01-01

    The present paper aims at understanding the biomechanics of an octopus tentacle as preliminary work for designing and developing a new robotic octopus tentacle. The biomechanical characterization of the biological material has been carried out on samples of Octopus vulgaris tentacles with engineering methods and tools, i.e. by biomechanical measurements of the tentacle elasticity and tension-compression stress/stretch curves. Another part of the activities has been devoted to the study of materials that can reproduce the viscoelastic behavior of the tentacle. The work presented here is part of the ongoing study and analysis on new design principles for actuation, sensing, and manipulation control, for robots with increased performance, in terms of dexterity, control, flexibility, applicability.

  9. LINCS: Livermore's network architecture. [Octopus computing network

    SciTech Connect

    Fletcher, J.G.

    1982-01-01

    Octopus, a local computing network that has been evolving at the Lawrence Livermore National Laboratory for over fifteen years, is currently undergoing a major revision. The primary purpose of the revision is to consolidate and redefine the variety of conventions and formats, which have grown up over the years, into a single standard family of protocols, the Livermore Interactive Network Communication Standard (LINCS). This standard treats the entire network as a single distributed operating system such that access to a computing resource is obtained in a single way, whether that resource is local (on the same computer as the accessing process) or remote (on another computer). LINCS encompasses not only communication but also such issues as the relationship of customer to server processes and the structure, naming, and protection of resources. The discussion includes: an overview of the Livermore user community and computing hardware, the functions and structure of each of the seven layers of LINCS protocol, the reasons why we have designed our own protocols and why we are dissatisfied by the directions that current protocol standards are taking.

  10. Role of olfaction in Octopus vulgaris reproduction.

    PubMed

    Polese, Gianluca; Bertapelle, Carla; Di Cosmo, Anna

    2015-01-01

    The olfactory system in any animal is the primary sensory system that responds to chemical stimuli emanating from a distant source. In aquatic animals "Odours" are molecules in solution that guide them to locate food, partners, nesting sites, and dangers to avoid. Fish, crustaceans and aquatic molluscs possess sensory systems that have anatomical similarities to the olfactory systems of land-based animals. Molluscs are a large group of aquatic and terrestrial animals that rely heavily on chemical communication with a generally dispersed sense of touch and chemical sensitivity. Cephalopods, the smallest class among extant marine molluscs, are predators with high visual capability and well developed vestibular, auditory, and tactile systems. Nevertheless they possess a well developed olfactory organ, but to date almost nothing is known about the mechanisms, functions and modulation of this chemosensory structure in octopods. Cephalopod brains are the largest of all invertebrate brains and across molluscs show the highest degree of centralization. The reproductive behaviour of Octopus vulgaris is under the control of a complex set of signal molecules such as neuropeptides, neurotransmitters and sex steroids that guide the behaviour from the level of individuals in evaluating mates, to stimulating or deterring copulation, to sperm-egg chemical signalling that promotes fertilization. These signals are intercepted by the olfactory organs and integrated in the olfactory lobes in the central nervous system. In this context we propose a model in which the olfactory organ and the olfactory lobe of O. vulgaris could represent the on-off switch between food intake and reproduction.

  11. I Know My Neighbour: Individual Recognition in Octopus vulgaris

    PubMed Central

    Tricarico, Elena; Borrelli, Luciana; Gherardi, Francesca; Fiorito, Graziano

    2011-01-01

    Background Little is known about individual recognition (IR) in octopuses, although they have been abundantly studied for their sophisticated behaviour and learning capacities. Indeed, the ability of octopuses to recognise conspecifics is suggested by a number of clues emerging from both laboratory studies (where they appear to form and maintain dominance hierarchies) and field observations (octopuses of neighbouring dens display little agonism between each other). To fill this gap in knowledge, we investigated the behaviour of 24 size-matched pairs of Octopus vulgaris in laboratory conditions. Methodology/Principal Findings The experimental design was composed of 3 phases: Phase 1 (acclimatization): 12 “sight-allowed” (and 12 “isolated”) pairs were maintained for 3 days in contiguous tanks separated by a transparent (and opaque) partition to allow (and block) the vision of the conspecific; Phase 2 (cohabitation): members of each pair (both sight-allowed and isolated) were transferred into an experimental tank and were allowed to interact for 15 min every day for 3 consecutive days; Phase 3 (test): each pair (both sight-allowed and isolated) was subject to a switch of an octopus to form pairs composed of either familiar (“sham switches”) or unfamiliar conspecifics (“real switches”). Longer latencies (i.e. the time elapsed from the first interaction) and fewer physical contacts in the familiar pairs as opposed to the unfamiliar pairs were used as proxies for recognition. Conclusions Octopuses appear able to recognise conspecifics and to remember the individual previously met for at least one day. To the best of our knowledge, this is the first experimental study showing the occurrence of a form of IR in cephalopods. Future studies should clarify whether this is a “true” IR. PMID:21533257

  12. Behavior and Body Patterns of the Larger Pacific Striped Octopus.

    PubMed

    Caldwell, Roy L; Ross, Richard; Rodaniche, Arcadio; Huffard, Christine L

    2015-01-01

    Over thirty years ago anecdotal accounts of the undescribed Larger Pacific Striped Octopus suggested behaviors previously unknown for octopuses. Beak-to-beak mating, dens shared by mating pairs, inking during mating and extended spawning were mentioned in publications, and enticed generations of cephalopod biologists. In 2012-2014 we were able to obtain several live specimens of this species, which remains without a formal description. All of the unique behaviors listed above were observed for animals in aquaria and are discussed here. We describe the behavior, body color patterns, and postures of 24 adults maintained in captivity. Chromatophore patterns of hatchlings are also shown.

  13. Behavior and Body Patterns of the Larger Pacific Striped Octopus

    PubMed Central

    Caldwell, Roy L.; Ross, Richard; Rodaniche, Arcadio; Huffard, Christine L.

    2015-01-01

    Over thirty years ago anecdotal accounts of the undescribed Larger Pacific Striped Octopus suggested behaviors previously unknown for octopuses. Beak-to-beak mating, dens shared by mating pairs, inking during mating and extended spawning were mentioned in publications, and enticed generations of cephalopod biologists. In 2012–2014 we were able to obtain several live specimens of this species, which remains without a formal description. All of the unique behaviors listed above were observed for animals in aquaria and are discussed here. We describe the behavior, body color patterns, and postures of 24 adults maintained in captivity. Chromatophore patterns of hatchlings are also shown. PMID:26266543

  14. Behavior and Body Patterns of the Larger Pacific Striped Octopus.

    PubMed

    Caldwell, Roy L; Ross, Richard; Rodaniche, Arcadio; Huffard, Christine L

    2015-01-01

    Over thirty years ago anecdotal accounts of the undescribed Larger Pacific Striped Octopus suggested behaviors previously unknown for octopuses. Beak-to-beak mating, dens shared by mating pairs, inking during mating and extended spawning were mentioned in publications, and enticed generations of cephalopod biologists. In 2012-2014 we were able to obtain several live specimens of this species, which remains without a formal description. All of the unique behaviors listed above were observed for animals in aquaria and are discussed here. We describe the behavior, body color patterns, and postures of 24 adults maintained in captivity. Chromatophore patterns of hatchlings are also shown. PMID:26266543

  15. Isolation and characterization of novel tachykinins from the posterior salivary gland of the common octopus Octopus vulgaris.

    PubMed

    Kanda, Atsuhiro; Iwakoshi-Ukena, Eiko; Takuwa-Kuroda, Kyoko; Minakata, Hiroyuki

    2003-01-01

    Two novel tachykinins (OctTK-I: Lys-Pro-Pro-Ser-Ser-Ser-Glu-Phe-Ile-Gly-Leu-Met-NH(2) and OctTK-II: Lys-Pro-Pro-Ser-Ser-Ser-Glu-Phe-Val-Gly-Leu-Met-NH(2)) were isolated from the posterior salivary gland of the octopus (Octopus vulgaris) using a contraction assay of the carp rectum. These peptides had in common the pentapeptide sequence -Phe-X-Gly-Leu-Met-NH(2) at the C-terminal and induced immediate contractions on the carp rectum and the guinea-pig ileum. cDNAs encoding their precursor proteins were cloned. The OctTK gene was expressed in the posterior salivary gland and the expression was localized in mucus-secreting cells of the gland. The results suggested that OctTKs might be secreted as a venomous substance acting on vertebrates such as fishes, which are the prey or natural enemies of the octopus. PMID:12576083

  16. Oxygen equilibria of Octopus dofleini hemocyanin.

    PubMed

    Miller, K I

    1985-08-13

    Oxygen binding by Octopus dofleini hemocyanin was examined under very nearly physiological conditions. The effects of pH, ionic composition, temperature, and aggregation were controlled so that the role each plays in modulating oxygen binding can be isolated. There is a very large effect of pH on affinity, the Bohr effect (delta log P50/delta pH = -1.7), which is the same at 10 and 20 degrees C. However, cooperativity is substantially altered over the same range of pHs at the two temperatures. The allosteric properties were examined by comparing the experimental data points to curves generated by use of the Monod-Wyman-Changeux model. A computer-fitting process was developed which allowed the individual allosteric parameters to be varied independently until the best fit could be determined. The relationship between kR and kT is responsible for the effect of pH on cooperativity. A change in the allosteric properties of the T form is primarily responsible for the differences due to temperature. Changing cation concentrations when the molecule is in the fully aggregated 51S form alters affinity without influencing cooperativity. The effect of Mg2+ is much greater than that of Na+. If the 51S decamer is dissociated to 11S monomers by removing divalent cations, oxygen binding is noncooperative. There is evidence for negative cooperativity, indicating heterogeneity of function within the subunit which contains seven oxygen binding domains. Association into decamers generates conformational change which results in a much wider range of allosteric function. PMID:4063340

  17. Role of olfaction in Octopus vulgaris reproduction.

    PubMed

    Polese, Gianluca; Bertapelle, Carla; Di Cosmo, Anna

    2015-01-01

    The olfactory system in any animal is the primary sensory system that responds to chemical stimuli emanating from a distant source. In aquatic animals "Odours" are molecules in solution that guide them to locate food, partners, nesting sites, and dangers to avoid. Fish, crustaceans and aquatic molluscs possess sensory systems that have anatomical similarities to the olfactory systems of land-based animals. Molluscs are a large group of aquatic and terrestrial animals that rely heavily on chemical communication with a generally dispersed sense of touch and chemical sensitivity. Cephalopods, the smallest class among extant marine molluscs, are predators with high visual capability and well developed vestibular, auditory, and tactile systems. Nevertheless they possess a well developed olfactory organ, but to date almost nothing is known about the mechanisms, functions and modulation of this chemosensory structure in octopods. Cephalopod brains are the largest of all invertebrate brains and across molluscs show the highest degree of centralization. The reproductive behaviour of Octopus vulgaris is under the control of a complex set of signal molecules such as neuropeptides, neurotransmitters and sex steroids that guide the behaviour from the level of individuals in evaluating mates, to stimulating or deterring copulation, to sperm-egg chemical signalling that promotes fertilization. These signals are intercepted by the olfactory organs and integrated in the olfactory lobes in the central nervous system. In this context we propose a model in which the olfactory organ and the olfactory lobe of O. vulgaris could represent the on-off switch between food intake and reproduction. PMID:25449183

  18. Morphologic, cytometric and functional characterization of the common octopus (Octopus vulgaris) hemocytes.

    PubMed

    Castellanos-Martínez, S; Prado-Alvarez, M; Lobo-da-Cunha, A; Azevedo, C; Gestal, C

    2014-05-01

    The hemocytes of Octopus vulgaris were morphologically and functionally characterized. Light and electron microscopy (TEM and SEM), and flow cytometry analyses revealed the existence of two hemocyte populations. Large granulocytes showed U-shaped nucleus, a mean of 11.6 μm±1.2 in diameter with basophilic granules, polysaccharide and lysosomic deposits in the cytoplasm. Small granulocytes measured a mean of 8.1 μm±0.7 in diameter, and have a round nucleus occupying almost the entire cell and few or not granules in the cytoplasm. Flow cytometry analysis showed that large granulocytes are the principal cells that develop phagocytosis of latex beads (rising up to 56%) and ROS after zymosan stimulation. Zymosan induced the highest production of both ROS and NO. This study is the first tread towards understanding the O. vulgaris immune system by applying new tools to provide a most comprehensive morpho-functional study of their hemocytes. PMID:24296436

  19. Morphologic, cytometric and functional characterization of the common octopus (Octopus vulgaris) hemocytes.

    PubMed

    Castellanos-Martínez, S; Prado-Alvarez, M; Lobo-da-Cunha, A; Azevedo, C; Gestal, C

    2014-05-01

    The hemocytes of Octopus vulgaris were morphologically and functionally characterized. Light and electron microscopy (TEM and SEM), and flow cytometry analyses revealed the existence of two hemocyte populations. Large granulocytes showed U-shaped nucleus, a mean of 11.6 μm±1.2 in diameter with basophilic granules, polysaccharide and lysosomic deposits in the cytoplasm. Small granulocytes measured a mean of 8.1 μm±0.7 in diameter, and have a round nucleus occupying almost the entire cell and few or not granules in the cytoplasm. Flow cytometry analysis showed that large granulocytes are the principal cells that develop phagocytosis of latex beads (rising up to 56%) and ROS after zymosan stimulation. Zymosan induced the highest production of both ROS and NO. This study is the first tread towards understanding the O. vulgaris immune system by applying new tools to provide a most comprehensive morpho-functional study of their hemocytes.

  20. The inkless octopuses (Cephalopoda: Octopodidae) of the southwest Atlantic.

    PubMed

    Gleadall, Ian G; Guerrero-Kommritz, Juergen; Hochberg, Frederick G; Laptikhovsky, Vladimir V

    2010-06-01

    Three inkless octopodids are described from the continental shelf off southeastern South America. These octopuses are a non-commercial by-catch in the Falkland Islands fishery. Muusoctopus eureka (Robson, 1929) is one of two common inkless octopuses and is of medium size, with orange-pink skin and a distinctive pattern of irregular dark markings, interspersed with white spots visible only in living or freshly dead specimens. The second common inkless octopus is M. longibrachus akambei, a new subspecies of the Chilean species Muusoctopus longibrachus ( Ibáñez, Sepúlveda and Chong, 2006 ). It has slender arms and is much larger at full maturity than M. eureka. It is a plain orange color when alive, pinkish cream when preserved. Muusoctopus bizikovi, sp. nov., is a smaller, rarer species, colored wine-red whether alive or preserved, and has a vestigial ink duct between the digestive gland and the anus. Relations with other species are discussed. This group of octopuses has often been associated with the genus Benthoctopus Grimpe, 1921 , which is a junior synonym of Bathypolypus Grimpe (a genus of small species characterized by much shorter arms and males with a robust copulatory organ bearing transverse lamellae). It is argued that the misleading characterization of the so-called Benthoctopus group of species as "smooth skinned" is based upon the artefactual appearance of specimens fixed and preserved suboptimally following a detrimental freeze-thaw cycle of fisheries material previously frozen while at sea.

  1. Nervous control of reproduction in Octopus vulgaris: a new model.

    PubMed

    Di Cristo, Carlo

    2013-06-01

    The classic study of Wells and Wells on the control of reproduction in Octopus demonstrated that the activity of the subpedunculate lobe of the brain and environmental illumination both inhibit the release of an unknown gonadotropin from the optic gland. This inhibitory control may be exerted by the neuropeptide Phe-Met-Arg-Phe-NH₂ (FMRFamide). It was later demonstrated that the olfactory lobe is also likely to be involved in the control of optic gland activity. The presence of gonadotropin-releasing hormone in the olfactory lobe suggested that it might exert an excitatory action on optic gland activity. Other neuropeptides have now been localised in the olfactory lobe: neuropeptide Y, galanin, corticotropin-releasing factor, Ala-Pro-Gly-Trp-NH₂ (APGWamide), as well as steroidogenic enzymes and an oestrogen receptor orthologue. This supports the hypothesis that this lobe may also play a part in the control of reproduction in Octopus. The olfactory lobe receives distant chemical stimuli and also appears to be an integrative centre containing a variety of neuropeptides involved in controlling the onset of sexual maturation of Octopus, via the optic gland hormone. This review attempts to summarise current knowledge about the role of the olfactory lobe and optic gland in the control of sexual maturation in Octopus, in the light of new findings and in the context of molluscan comparative physiology.

  2. Dancing With an Octopus: The Graceful Art of Collaboration

    ERIC Educational Resources Information Center

    Russell, Elizabeth Morgan

    2008-01-01

    Collaboration--working with like-minded others to achieve a common purpose--is an action-oriented strategy that can be considered as a way of reaching your goals. Because collaboration, as in dancing with an octopus, requires keeping track of many different points (or tentacles), planners who know when collaborations are more likely to work and…

  3. Video playback demonstrates episodic personality in the gloomy octopus.

    PubMed

    Pronk, R; Wilson, D R; Harcourt, R

    2010-04-01

    Coleoid cephalopods, including octopuses, cuttlefish and squid, rely mainly on visual signals when interacting with conspecifics, predators and prey. Presenting visual stimuli, such as models, photographs, mirrors and live conspecifics, can thus provide insight into cephalopod behaviour. These methods, however, have limitations - mirrors and live animals lack experimental control, whereas models and photographs sacrifice motion-based information. Video playback addresses these issues by presenting controlled, moving and realistic stimuli but, to date, video playback has not been used successfully with any cephalopod. Here, we developed a video playback technique for the gloomy octopus (Octopus tetricus) that incorporated recent advances in video technology. We then used this technique to test for personality, which we defined as behavioural differences between individuals that are consistent over time and across ecologically important contexts. We captured wild octopuses and tested them on 3 separate days over a 10 day period. On each test day, subjects were presented with videos of a food item, a novel object and a conspecific. These represented a foraging, novel and threatening context, respectively. A fourth video without a moving stimulus controlled for the playback monitor itself and potential artifacts associated with video playback. Experimental stimuli evoked unambiguous and biologically appropriate responses from the subjects. Furthermore, individuals' responses to the three experimental contexts were highly correlated within a given test day. However, within a given context, individuals behaved inconsistently across the 3 test days. The reordering of ranks suggests that rather than fulfilling the criteria for personality, gloomy octopus show temporal discontinuities, and hence display episodic personality.

  4. Resonance Raman spectroscopy of octopus rhodopsin and its photoproducts

    SciTech Connect

    Pande, C.; Pande, A.; Yue, K.T.; Callender, R.; Ebrey, T.G.; Tsuda, M.

    1987-08-11

    The authors report here the resonance Raman spectra of octopus rhodopsin and its photoproducts, bathorhodopsin and acid metarhodopsin. These studies were undertaken in order to make comparisons with the well-studied bovine pigments, so as to understand the similarities and the differences in pigment structure and photochemical processes between vertebrates and invertebrates. The flow method was used to obtain the Raman spectrum of rhodopsin at 13 /sup 0/C. The bathorhodopsin spectrum was obtained by computer subtraction of the spectra containing different photostationary mixtures of rhodopsin, isorhodopsin, hypsorhodopsin, and bathorhodopsin, obtained at 12 K using the pump-probe technique and from measurements at 80 K. Like their bovine counterparts, the Schiff base vibrational mode appears at approx. 1660 cm/sup -1/ in octopus rhodopsin and the photoproducts, bathorhodopsin and acid metarhodopsin, suggesting a proteonated Schiff base linkage between the chromophore and the protein. Differences between the Raman spectra of octopus rhodopsin and bathorhodopsin indicate that the formation of bathorhodopsin is associated with chromophore isomerization. This inference is substantiated by the chromophore chemical extraction data which show that, like the bovine system, octopus rhodopsin is an 11-cis pigment, while the photoproducts contain an all-trans pigment, in agreement with the previous work. The octopus rhodopsin and bathorhodopsin spectra show marked differences from their bovine counterparts in other respects, however. The differences are most dramatic in the structure-sensitive fingerprint and the HOOP regions. Thus, it appears that although the two species differ in the specific nature of the chromophore-protein interactions, the general process of visual transduction is the same.

  5. Brain and behavioural evidence for rest-activity cycles in Octopus vulgaris.

    PubMed

    Brown, Euan R; Piscopo, Stefania; De Stefano, Rosanna; Giuditta, Antonio

    2006-09-25

    Octopus vulgaris maintained under a 12/12h light/dark cycle exhibit a pronounced nocturnal activity pattern. Animals deprived of rest during the light period show a marked 'rebound' in activity in the following 24h. 'Active' octopuses attack faster than 'quiet' animals and brain activity recorded electrically intensifies during 'quiet' behaviour. Thus, in Octopus as in vertebrates, brain areas involved in memory or 'higher' processes exhibit 'off-line' activity during rest periods.

  6. Toxin and species identification of toxic octopus implicated into food poisoning in Taiwan.

    PubMed

    Wu, Ya-Jung; Lin, Chun-Lan; Chen, Chien-Hung; Hsieh, Cheng-Hong; Jen, Hsiao-Chin; Jian, Shi-Jie; Hwang, Deng-Fwu

    2014-12-01

    A food poisoning incident due to ingestion of unknown octopus occurred in Taipei in December, 2010. The serum and urine from victims (male 38 and 43 years old) were collected, determined the toxicity, and identified tetrodotoxin (TTX) by high-performance liquid chromatography with tandem mass spectrometry (LC-MS/MS). It was found that only urine contained the trace of TTX. Then, two retained specimen (one without blue ring in the skin and another with small blue ring in the skin) were collected from victims and examined for the toxicity and toxin. Meanwhile, 6 specimens of octopus without blue ring in the skin and 4 specimens of octopus with blue ring in the skin were re-collected from the market. Both retained octopus samples were found to contain TTX. However, re-collected market's octopus without blue ring in the skin did not show to contain TTX the and was identified as Octopus aegina by using the analysis of cytochrome b gene (Cyt b) and cytochrome c oxidase subunit I gene (COI). Only octopus with blue ring in the skin contained TTX and was identified as Hapalochlaena fasciata by using the analysis of Cyt b and COI. Therefore, this octopus food poisoning was caused by toxic octopus H. fasciata and the causative agent was TTX. PMID:25286395

  7. Toxin and species identification of toxic octopus implicated into food poisoning in Taiwan.

    PubMed

    Wu, Ya-Jung; Lin, Chun-Lan; Chen, Chien-Hung; Hsieh, Cheng-Hong; Jen, Hsiao-Chin; Jian, Shi-Jie; Hwang, Deng-Fwu

    2014-12-01

    A food poisoning incident due to ingestion of unknown octopus occurred in Taipei in December, 2010. The serum and urine from victims (male 38 and 43 years old) were collected, determined the toxicity, and identified tetrodotoxin (TTX) by high-performance liquid chromatography with tandem mass spectrometry (LC-MS/MS). It was found that only urine contained the trace of TTX. Then, two retained specimen (one without blue ring in the skin and another with small blue ring in the skin) were collected from victims and examined for the toxicity and toxin. Meanwhile, 6 specimens of octopus without blue ring in the skin and 4 specimens of octopus with blue ring in the skin were re-collected from the market. Both retained octopus samples were found to contain TTX. However, re-collected market's octopus without blue ring in the skin did not show to contain TTX the and was identified as Octopus aegina by using the analysis of cytochrome b gene (Cyt b) and cytochrome c oxidase subunit I gene (COI). Only octopus with blue ring in the skin contained TTX and was identified as Hapalochlaena fasciata by using the analysis of Cyt b and COI. Therefore, this octopus food poisoning was caused by toxic octopus H. fasciata and the causative agent was TTX.

  8. Elastic arteries in invertebrates: mechanics of the octopus aorta.

    PubMed

    Shadwick, R E; Gosline, J M

    1981-08-14

    The aorta of the octopus, Octopus dofleini, is a highly distensible, elastic tube. The circumferential elastic modulus increases with inflation in the physiological range from abut 10(4) to 10(5) newtons per square meter. Rubber-like fibers have been isolated, apparently for the first time, from the aorta of an invertebrate. These fibers have an elastic modulus, like elastin, of about 4 x 10(5) newtons per square meter and are present in sufficient quantity to account for the elastic properties of the intact vessel under physiological conditions. Thus the circulatory system of an invertebrate animal provides an "elastic reservoir" (much like that of the vertebrate system), which increases the efficiency of the circulation. PMID:7256277

  9. Octopus arm choice is strongly influenced by eye use.

    PubMed

    Byrne, Ruth A; Kuba, Michael J; Meisel, Daniela V; Griebel, Ulrike; Mather, Jennifer A

    2006-09-25

    This study aims to investigate the octopus' eye and arm coordination and raises the question if visual guidance determines choice of arm use. Octopuses possess eight seemingly identical arms but have recently been reported to show a preference as to which arm they use to initiate contact with objects. These animals also exhibit lateralized eye use, therefore, a connection between eye and arm preference seems possible. Seven Octopus vulgaris were observed during approach, contact initiation and exploration of plastic objects that were positioned on three different levels in the water column. The subjects most commonly used an arm to initiate contact with an object that was in a direct line between the eye used to look at the object, and the object itself. This indicates that choice of arm use is spatially rather opportunistic when depending on visual guidance. Additionally, first contact with an object was usually established by the central third of the arm and in arm contact sequences neighboring arms were the most likely to follow an arm already touching the object. Although results point towards strong eye/arm coordination, we did not find lateralized behavior in this experiment. Results are discussed from a neuro-anatomical, behavioral and ecological perspective.

  10. Octopus-like suction cups: from natural to artificial solutions.

    PubMed

    Tramacere, F; Follador, M; Pugno, N M; Mazzolai, B

    2015-05-13

    Octopus suckers are able to attach to all nonporous surfaces and generate a very strong attachment force. The well-known attachment features of this animal result from the softness of the sucker tissues and the surface morphology of the portion of the sucker that is in contact with objects or substrates. Unlike artificial suction cups, octopus suckers are characterized by a series of radial grooves that increase the area subjected to pressure reduction during attachment. In this study, we constructed artificial suction cups with different surface geometries and tested their attachment performances using a pull-off setup. First, smooth suction cups were obtained for casting; then, sucker surfaces were engraved with a laser cutter. As expected, for all the tested cases, the engraving treatment enhanced the attachment performance of the elastomeric suction cups compared with that of the smooth versions. Moreover, the results indicated that the surface geometry with the best attachment performance was the geometry most similar to octopus sucker morphology. The results obtained in this work can be utilized to design artificial suction cups with higher wet attachment performance.

  11. Octopus-like suction cups: from natural to artificial solutions.

    PubMed

    Tramacere, F; Follador, M; Pugno, N M; Mazzolai, B

    2015-06-01

    Octopus suckers are able to attach to all nonporous surfaces and generate a very strong attachment force. The well-known attachment features of this animal result from the softness of the sucker tissues and the surface morphology of the portion of the sucker that is in contact with objects or substrates. Unlike artificial suction cups, octopus suckers are characterized by a series of radial grooves that increase the area subjected to pressure reduction during attachment. In this study, we constructed artificial suction cups with different surface geometries and tested their attachment performances using a pull-off setup. First, smooth suction cups were obtained for casting; then, sucker surfaces were engraved with a laser cutter. As expected, for all the tested cases, the engraving treatment enhanced the attachment performance of the elastomeric suction cups compared with that of the smooth versions. Moreover, the results indicated that the surface geometry with the best attachment performance was the geometry most similar to octopus sucker morphology. The results obtained in this work can be utilized to design artificial suction cups with higher wet attachment performance. PMID:25970079

  12. Structure and mechanical properties of Octopus vulgaris suckers.

    PubMed

    Tramacere, Francesca; Kovalev, Alexander; Kleinteich, Thomas; Gorb, Stanislav N; Mazzolai, Barbara

    2014-02-01

    In this study, we investigate the morphology and mechanical features of Octopus vulgaris suckers, which may serve as a model for the creation of a new generation of attachment devices. Octopus suckers attach to a wide range of substrates in wet conditions, including rough surfaces. This amazing feature is made possible by the sucker's tissues, which are pliable to the substrate profile. Previous studies have described a peculiar internal structure that plays a fundamental role in the attachment and detachment processes of the sucker. In this work, we present a mechanical characterization of the tissues involved in the attachment process, which was performed using microindentation tests. We evaluated the elasticity modulus and viscoelastic parameters of the natural tissues (E ∼ 10 kPa) and measured the mechanical properties of some artificial materials that have previously been used in soft robotics. Such a comparison of biological prototypes and artificial material that mimics octopus-sucker tissue is crucial for the design of innovative artificial suction cups for use in wet environments. We conclude that the properties of the common elastomers that are generally used in soft robotics are quite dissimilar to the properties of biological suckers. PMID:24284894

  13. Structure and mechanical properties of Octopus vulgaris suckers

    PubMed Central

    Tramacere, Francesca; Kovalev, Alexander; Kleinteich, Thomas; Gorb, Stanislav N.; Mazzolai, Barbara

    2014-01-01

    In this study, we investigate the morphology and mechanical features of Octopus vulgaris suckers, which may serve as a model for the creation of a new generation of attachment devices. Octopus suckers attach to a wide range of substrates in wet conditions, including rough surfaces. This amazing feature is made possible by the sucker's tissues, which are pliable to the substrate profile. Previous studies have described a peculiar internal structure that plays a fundamental role in the attachment and detachment processes of the sucker. In this work, we present a mechanical characterization of the tissues involved in the attachment process, which was performed using microindentation tests. We evaluated the elasticity modulus and viscoelastic parameters of the natural tissues (E ∼ 10 kPa) and measured the mechanical properties of some artificial materials that have previously been used in soft robotics. Such a comparison of biological prototypes and artificial material that mimics octopus-sucker tissue is crucial for the design of innovative artificial suction cups for use in wet environments. We conclude that the properties of the common elastomers that are generally used in soft robotics are quite dissimilar to the properties of biological suckers. PMID:24284894

  14. Structure and mechanical properties of Octopus vulgaris suckers.

    PubMed

    Tramacere, Francesca; Kovalev, Alexander; Kleinteich, Thomas; Gorb, Stanislav N; Mazzolai, Barbara

    2014-02-01

    In this study, we investigate the morphology and mechanical features of Octopus vulgaris suckers, which may serve as a model for the creation of a new generation of attachment devices. Octopus suckers attach to a wide range of substrates in wet conditions, including rough surfaces. This amazing feature is made possible by the sucker's tissues, which are pliable to the substrate profile. Previous studies have described a peculiar internal structure that plays a fundamental role in the attachment and detachment processes of the sucker. In this work, we present a mechanical characterization of the tissues involved in the attachment process, which was performed using microindentation tests. We evaluated the elasticity modulus and viscoelastic parameters of the natural tissues (E ∼ 10 kPa) and measured the mechanical properties of some artificial materials that have previously been used in soft robotics. Such a comparison of biological prototypes and artificial material that mimics octopus-sucker tissue is crucial for the design of innovative artificial suction cups for use in wet environments. We conclude that the properties of the common elastomers that are generally used in soft robotics are quite dissimilar to the properties of biological suckers.

  15. Regeneration of bovine and octopus opsins in situ with natural and artificial retinals

    SciTech Connect

    Koutalos, Y.; Ebrey, T.G.; Tsuda, M.; Odashima, K.; Lien, T.; Park, M.H.; Shimizu, N.; Derguini, F.; Nakanishi, K.; Gilson, H.R.; Honig, B. )

    1989-03-21

    The authors consider the problem of color regulation in visual pigments for both bovine rhodopsin and octopus rhodopsin. Both pigments have 11-cis-retinal as their chromophore. These rhodopsins were bleached in their native membranes, and the opsins were regenerated with natural and artificial chromophores. Both bovine and octopus opsins were regenerated with the 9-cis- and 11-cis-retinal isomers, but the octopus opsin was additionally regenerated with the 13-cis and all-trans isomers. Titration of the octopus opsin with 11-cis-retinal gave an extinction coefficient for octopus rhodopsin of 27,000 {plus minus} 3,000 M{sup {minus}1} cm{sup {minus}1} at 475 nm. The absorption maxima of bovine artificial pigments formed by regenerating opsin with the 11-cis dihydro series of chromophores support a color regulation model for bovine rhodopsin in which the chromophore-binding site of the protein has two negative charges: one directly hydrogen bonded to the Schiff base nitrogen and another near carbon-13. Formation of octopus artificial pigments with both all-trans and 11-cis dihydro chromophores leads to a similar model for octopus rhodopsin and metarhodopsin: there are two negative charges in the chromophore-binding site, one directly hydrogen bonded to the Schiff base nitrogen and a second near carbon-13. The interaction of this second charge with the chromophore in octopus rhodopsin is weaker than in bovine, while in metarhodopsin it is as strong as in bovine.

  16. When do octopuses play? Effects of repeated testing, object type, age, and food deprivation on object play in Octopus vulgaris.

    PubMed

    Kuba, Michael J; Byrne, Ruth A; Meisel, Daniela V; Mather, Jennifer A

    2006-08-01

    Studying play behavior in octopuses is an important step toward understanding the phylogenetic origins and function of play as well as the cognitive abilities of invertebrates. Fourteen Octopus vulgaris (7 subadults and 7 adults) were presented 2 Lego objects and 2 different food items on 7 consecutive days under 2 different levels of food deprivation. Nine subjects showed play-like behavior with the Lego objects. There was no significant difference in play-like behavior corresponding to food deprivation, age, and sex of the octopuses. The sequence of behaviors, from exploration to play-like behavior, had a significant influence on the establishment of play-like behavior, as it occurred mostly on Days 3-6 of the 7-day experiment. The pattern of development of play-like activities after a period of exploration and habituation in this study agrees with the hypothesis that object play follows object exploration. A homologous origin of this behavioral trait in vertebrates and invertebrates is highly unlikely, as the last common ancestor might not have had the cognitive capacity to possess this trait.

  17. Bioinspired locomotion and grasping in water: the soft eight-arm OCTOPUS robot.

    PubMed

    Cianchetti, M; Calisti, M; Margheri, L; Kuba, M; Laschi, C

    2015-06-01

    The octopus is an interesting model for the development of soft robotics, due to its high deformability, dexterity and rich behavioural repertoire. To investigate the principles of octopus dexterity, we designed an eight-arm soft robot and evaluated its performance with focused experiments. The OCTOPUS robot presented here is a completely soft robot, which integrates eight arms extending in radial direction and a central body which contains the main processing units. The front arms are mainly used for elongation and grasping, while the others are mainly used for locomotion. The robotic octopus works in water and its buoyancy is close to neutral. The experimental results show that the octopus-inspired robot can walk in water using the same strategy as the animal model, with good performance over different surfaces, including walking through physical constraints. It can grasp objects of different sizes and shapes, thanks to its soft arm materials and conical shape. PMID:25970014

  18. Bioinspired locomotion and grasping in water: the soft eight-arm OCTOPUS robot.

    PubMed

    Cianchetti, M; Calisti, M; Margheri, L; Kuba, M; Laschi, C

    2015-05-13

    The octopus is an interesting model for the development of soft robotics, due to its high deformability, dexterity and rich behavioural repertoire. To investigate the principles of octopus dexterity, we designed an eight-arm soft robot and evaluated its performance with focused experiments. The OCTOPUS robot presented here is a completely soft robot, which integrates eight arms extending in radial direction and a central body which contains the main processing units. The front arms are mainly used for elongation and grasping, while the others are mainly used for locomotion. The robotic octopus works in water and its buoyancy is close to neutral. The experimental results show that the octopus-inspired robot can walk in water using the same strategy as the animal model, with good performance over different surfaces, including walking through physical constraints. It can grasp objects of different sizes and shapes, thanks to its soft arm materials and conical shape.

  19. Effect of additives in the shelflife extension of chilled and frozen stored Indian octopus (Cistopus indicus).

    PubMed

    Manimaran, Uthaman; Shakila, Robinson Jeya; Shalini, Rajendran; Sivaraman, Balasubramanian; Sumathi, Ganesan; Selvaganapathi, Rajendran; Jeyasekaran, Geevarathnam

    2016-02-01

    In this study, the effect of commercial additives viz. cafodos and altesa employed to treat Indian octopus (Cistopus indicus) was examined during chilled and frozen storage. Shelf lives of treated and untreated octopus in ice were 6 and 8 days, respectively in ice. Treated and untreated frozen octopus had a shelf life of 40 days. Autolytic and microbiological changes were not controlled by the additives, as evidenced through rapid reduction in non-protein nitrogen (NPN) and α-amino nitrogen (α-AN) compounds; as well as accumulation of water soluble ammoniacal nitrogen and total volatile base- nitrogen (TVB-N) compounds. Loss of texture and colour were the major quality defects noticed in treated octopus as a result of enhanced protein solubility. Therefore, the additives approved for use in octopus neither enhanced the shelf life nor improved the sensory quality. PMID:27162416

  20. Detection and temporal variation of (60)Co in the digestive glands of the common octopus, Octopus vulgaris, in the East China Sea.

    PubMed

    Morita, Takami; Otosaka, Shigeyoshi; Fujimoto, Ken; Nishiuchi, Kou; Kimoto, Katsunori; Yamada, Haruya; Kasai, Hiromi; Minakawa, Masayuki; Yoshida, Katsuhiko

    2010-08-01

    (60)Co were detected in common octopus specimens collected in the East China Sea in 1996-2005. The source of (60)Co has remained unclear yet. Stable isotope analyses showed that there was no difference in stable Co concentrations between octopus samples with (60)Co and without (60)Co. This result showed that the stable Co in the digestive gland of octopus potentially did not include a trace amount of (60)Co and the source of (60)Co existed independently. Furthermore, investigations of octopus in other area and other species indicated that the origin of the source of (60)Co occurred locally in the restricted area in the East China Sea and not in the coastal area of Japan. Concentrations of (60)Co have annually decreased with shorter half-life than the physical half-life. This decrease tendency suggests that the sources of (60)Co were identical and were temporary dumped into the East China Sea as a solid waste.

  1. Use of octopus as a bioindicator species: Baseline studies

    SciTech Connect

    Holdway, D.A.; Butty, J.S.; Brennan, S.E.; Ahokas, J.T.

    1995-12-31

    The Australian octopus Octopus pallidus, is abundant, territorial, has a large digestive gland. This study was undertaken to assess octopii as a potential bioindicator species by establishing the efficacy of capturing octopi using traplines, and determining the impact of various modifying factors on the activities of digestive gland mixed-function oxidase (MFO) enzymes including ethoxyresorufin O-deethylase (EROD), ethoxycoumarin O-deethylase (ECOD) and total P-450. Trap success rates in Port Phillip Bay were 15--28% for the ``potentially contaminated`` site and 85% for the reference site. Cytochrome P-450 showed significant seasonal differences, with no site or sex differences. Mean ({+-} SE) Autumn P-450 values of 74.8 ({+-}5.5) pmol/mg protein were higher than Winter values of 51.2 ({+-}7.6), which were higher than Spring values of 21.8 ({+-}4.0) pmol/mg protein. Summer P-450 values of 61.4 ({+-} 9.8) pmol/mg protein were only different from Spring values. Mean ({+-} SE) Spring ECOD activity of 3.3 ({+-} 0.7) pmol/min/mg protein was lower than Summer, Autumn and Winter ECOD values of 8.9 ({+-} 1.6) 6.5 ({+-} 1.2) and 8.6 ({+-} 2.3) pmol/min/mg protein respectively. Females had roughly half the ECOD activities of males (3.8 {+-} 0.8 compared to 7.4 {+-} 0.9 pmol/min/mg protein). All octopi digestive gland EROD activities were low (roughly 0.2 pmol/min/mg protein) with no sex, site nor seasonal differences. Potential for using octopus as a bioindicator appears promising but sensitivity to chemical exposure has yet to be determined.

  2. Comparative analysis of gene expression for convergent evolution of camera eye between octopus and human.

    PubMed

    Ogura, Atsushi; Ikeo, Kazuho; Gojobori, Takashi

    2004-08-01

    Although the camera eye of the octopus is very similar to that of humans, phylogenetic and embryological analyses have suggested that their camera eyes have been acquired independently. It has been known as a typical example of convergent evolution. To study the molecular basis of convergent evolution of camera eyes, we conducted a comparative analysis of gene expression in octopus and human camera eyes. We sequenced 16,432 ESTs of the octopus eye, leading to 1052 nonredundant genes that have matches in the protein database. Comparing these 1052 genes with 13,303 already-known ESTs of the human eye, 729 (69.3%) genes were commonly expressed between the human and octopus eyes. On the contrary, when we compared octopus eye ESTs with human connective tissue ESTs, the expression similarity was quite low. To trace the evolutionary changes that are potentially responsible for camera eye formation, we also compared octopus-eye ESTs with the completed genome sequences of other organisms. We found that 1019 out of the 1052 genes had already existed at the common ancestor of bilateria, and 875 genes were conserved between humans and octopuses. It suggests that a larger number of conserved genes and their similar gene expression may be responsible for the convergent evolution of the camera eye.

  3. Seasonal patterns of polycyclic aromatic hydrocarbons in digestive gland and arm of octopus (Octopus vulgaris) from the Northwest Atlantic.

    PubMed

    Semedo, Miguel; Oliveira, Marta; Gomes, Filipa; Reis-Henriques, Maria Armanda; Delerue-Matos, Cristina; Morais, Simone; Ferreira, Marta

    2014-05-15

    Among organic pollutants existing in coastal areas, polycyclic aromatic hydrocarbons (PAHs) are of great concern due to their ubiquity and carcinogenic potential. The aim of this study was to evaluate the seasonal patterns of PAHs in the digestive gland and arm of the common octopus (Octopus vulgaris) from the Northwest Atlantic Portuguese coast. In the different seasons, 18 PAHs were determined and the detoxification capacity of the species was evaluated. Ethoxyresorufin O-deethylase (EROD) and ethoxycoumarin O-deethylase (ECOD) activities were measured to assess phase I biotransformation capacity. Individual PAH ratios were used for major source (pyrolytic/petrogenic) analysis. Risks for human consumption were determined by the total toxicity equivalence approach. Generally, low levels of PAHs were detected in the digestive gland and in the arm of octopus, with a predominance of low molecular over high molecular weight compounds. PAHs exhibited seasonality in the concentrations detected and in their main emission sources. In the digestive gland, the highest total PAH levels were observed in autumn possibly related to fat availability in the ecosystem and food intake. The lack of PAH elimination observed in the digestive gland after captivity could be possibly associated to a low biotransformation capacity, consistent with the negligible/undetected levels of EROD and ECOD activity in the different seasons. The emission sources of PAHs found in the digestive gland varied from a petrogenic profile observed in winter to a pyrolytic pattern in spring. In the arm, the highest PAH contents were observed in June; nevertheless, levels were always below the regulatory limits established for food consumption. The carcinogenic potential calculated for all the sampling periods in the arm were markedly lower than the ones found in various aquatic species from different marine environments. The results presented in this study give relevant baseline data for environmental

  4. Seasonal patterns of polycyclic aromatic hydrocarbons in digestive gland and arm of octopus (Octopus vulgaris) from the Northwest Atlantic.

    PubMed

    Semedo, Miguel; Oliveira, Marta; Gomes, Filipa; Reis-Henriques, Maria Armanda; Delerue-Matos, Cristina; Morais, Simone; Ferreira, Marta

    2014-05-15

    Among organic pollutants existing in coastal areas, polycyclic aromatic hydrocarbons (PAHs) are of great concern due to their ubiquity and carcinogenic potential. The aim of this study was to evaluate the seasonal patterns of PAHs in the digestive gland and arm of the common octopus (Octopus vulgaris) from the Northwest Atlantic Portuguese coast. In the different seasons, 18 PAHs were determined and the detoxification capacity of the species was evaluated. Ethoxyresorufin O-deethylase (EROD) and ethoxycoumarin O-deethylase (ECOD) activities were measured to assess phase I biotransformation capacity. Individual PAH ratios were used for major source (pyrolytic/petrogenic) analysis. Risks for human consumption were determined by the total toxicity equivalence approach. Generally, low levels of PAHs were detected in the digestive gland and in the arm of octopus, with a predominance of low molecular over high molecular weight compounds. PAHs exhibited seasonality in the concentrations detected and in their main emission sources. In the digestive gland, the highest total PAH levels were observed in autumn possibly related to fat availability in the ecosystem and food intake. The lack of PAH elimination observed in the digestive gland after captivity could be possibly associated to a low biotransformation capacity, consistent with the negligible/undetected levels of EROD and ECOD activity in the different seasons. The emission sources of PAHs found in the digestive gland varied from a petrogenic profile observed in winter to a pyrolytic pattern in spring. In the arm, the highest PAH contents were observed in June; nevertheless, levels were always below the regulatory limits established for food consumption. The carcinogenic potential calculated for all the sampling periods in the arm were markedly lower than the ones found in various aquatic species from different marine environments. The results presented in this study give relevant baseline data for environmental

  5. Dielectric elastomer actuators for octopus inspired suction cups.

    PubMed

    Follador, M; Tramacere, F; Mazzolai, B

    2014-09-25

    Suction cups are often found in nature as attachment strategy in water. Nevertheless, the application of the artificial counterpart is limited by the dimension of the actuators and their usability in wet conditions. A novel design for the development of a suction cup inspired by octopus suckers is presented. The main focus of this research was on the modelling and characterization of the actuation unit, and a first prototype of the suction cup was realized as a proof of concept. The actuation of the suction cup is based on dielectric elastomer actuators. The presented device works in a wet environment, has an integrated actuation system, and is soft. The dimensions of the artificial suction cups are comparable to proximal octopus suckers, and the attachment mechanism is similar to the biological counterpart. The design approach proposed for the actuator allows the definition of the parameters for its development and for obtaining a desired pressure in water. The fabricated actuator is able to produce up to 6 kPa of pressure in water, reaching the maximum pressure in less than 300 ms.

  6. Dielectric elastomer actuators for octopus inspired suction cups.

    PubMed

    Follador, M; Tramacere, F; Mazzolai, B

    2014-01-01

    Suction cups are often found in nature as attachment strategy in water. Nevertheless, the application of the artificial counterpart is limited by the dimension of the actuators and their usability in wet conditions. A novel design for the development of a suction cup inspired by octopus suckers is presented. The main focus of this research was on the modelling and characterization of the actuation unit, and a first prototype of the suction cup was realized as a proof of concept. The actuation of the suction cup is based on dielectric elastomer actuators. The presented device works in a wet environment, has an integrated actuation system, and is soft. The dimensions of the artificial suction cups are comparable to proximal octopus suckers, and the attachment mechanism is similar to the biological counterpart. The design approach proposed for the actuator allows the definition of the parameters for its development and for obtaining a desired pressure in water. The fabricated actuator is able to produce up to 6 kPa of pressure in water, reaching the maximum pressure in less than 300 ms. PMID:25253019

  7. Ultra-fast Escape of a Octopus-inspired Rocket

    NASA Astrophysics Data System (ADS)

    Weymouth, Gabriel; Triantafyllou, Michael

    2013-11-01

    The octopus, squid, and other cephalopods inflate with water and then release a jet to accelerate in the opposite direction. This escape mechanism is particularly interesting in the octopus because they become initially quite bluff, yet this does not hinder them in achieving impressive bursts of speed. We examine this somewhat paradoxical maneuver using a simple deflating spheroid model in both potential and viscous flow. We demonstrate that the dynamic reduction of the width of the body completely changes the flow and forces acting on the escaping rocket in three ways. First, a body which reduces in size can generate an added mass thrust which counteracts the added mass inertia. Second, the motion of the shrinking wall acts similar to suction on a static wall, reducing separation and drag forces in a viscous fluid, but that this effects depends on the rate of size change. Third, using a combination of these two features it is possible to initially load the fluid with kinetic energy when heavy and bluff and then recover that energy when streamlined and light, enabling ultra-fast accelerations. As a notable example, these mechanisms allow a shrinking spheroid rocket in a heavy inviscid fluid to achieve speeds greater than an identical rocket in the vacuum of space. Southampton Marine and Maritime Institute.

  8. Melatonin in octopus (Octopus vulgaris): tissue distribution, daily changes and relation with serotonin and its acid metabolite.

    PubMed

    Muñoz, José L P; López Patiño, Marcos A; Hermosilla, Consuelo; Conde-Sieira, Marta; Soengas, José L; Rocha, Francisco; Míguez, Jesús M

    2011-08-01

    Information regarding melatonin production in molluscs is very limited. In this study the presence and daily fluctuations of melatonin levels were investigated in hemolymph, retina and nervous system-related structures in the cephalopod Octopus vulgaris. Adult animals were maintained in captivity under natural photoperiod and killed at different times in a regular daily cycle. Levels of melatonin, serotonin (5-HT) and its acid metabolite (5-hydroxyindole acetic acid, 5-HIAA) in the hemolymph, retina, optic lobe, and cerebral ganglion were assayed by HPLC. Melatonin content fluctuated rhythmically in the retina and hemolymph, peaking at night. In the retina, but not in the other neural tissues, the rhythm was opposite to that of 5-HT, which displayed basal levels at night. Also, 5-HIAA levels in the retina were higher during the night, supporting that rhythmic melatonin production could be linked to diurnal changes in 5-HT degradation. The high levels of melatonin found in the retina point to it as the major source of melatonin in octopus; in addition, a large variation of melatonin content was found in the optic lobe with maximal values at night. All these data suggest that melatonin might play a role in the transduction of the light-dark cycle information for adjustment of rhythmic physiological events in cephalopods.

  9. The octopus: a model for a comparative analysis of the evolution of learning and memory mechanisms.

    PubMed

    Hochner, Binyamin; Shomrat, Tal; Fiorito, Graziano

    2006-06-01

    Comparative analysis of brain function in invertebrates with sophisticated behaviors, such as the octopus, may advance our understanding of the evolution of the neural processes that mediate complex behaviors. Until the last few years, this approach was infeasible due to the lack of neurophysiological tools for testing the neural circuits mediating learning and memory in the brains of octopus and other cephalopods. Now, for the first time, the adaptation of modern neurophysiological methods to the study of the central nervous system of the octopus allows this avenue of research. The emerging results suggest that a convergent evolutionary process has led to the selection of vertebrate-like neural organization and activity-dependent long-term synaptic plasticity. As octopuses and vertebrates are very remote phylogenetically, this convergence suggests the importance of the shared properties for the mediation of learning and memory.

  10. Camouflaging in a complex environment--octopuses use specific features of their surroundings for background matching.

    PubMed

    Josef, Noam; Amodio, Piero; Fiorito, Graziano; Shashar, Nadav

    2012-01-01

    Living under intense predation pressure, octopuses evolved an effective and impressive camouflaging ability that exploits features of their surroundings to enable them to "blend in." To achieve such background matching, an animal may use general resemblance and reproduce characteristics of its entire surroundings, or it may imitate a specific object in its immediate environment. Using image analysis algorithms, we examined correlations between octopuses and their backgrounds. Field experiments show that when camouflaging, Octopus cyanea and O. vulgaris base their body patterns on selected features of nearby objects rather than attempting to match a large field of view. Such an approach enables the octopus to camouflage in partly occluded environments and to solve the problem of differences in appearance as a function of the viewing inclination of the observer.

  11. Molecular phylogeny of the benthic shallow-water octopuses (Cephalopoda: Octopodinae).

    PubMed

    Guzik, Michelle T; Norman, Mark D; Crozier, Ross H

    2005-10-01

    Octopus has been regarded as a "catch all" genus, yet its monophyly is questionable and has been untested. We inferred a broad-scale phylogeny of the benthic shallow-water octopuses (subfamily Octopodinae) using amino acid sequences of two mitochondrial DNA genes: Cytochrome oxidase subunit III and Cytochrome b apoenzyme, and the nuclear DNA gene Elongation Factor-1alpha. Sequence data were obtained from 26 Octopus species and from four related genera. Maximum likelihood and Bayesian approaches were implemented to estimate the phylogeny, and non-parametric bootstrapping was used to verify confidence for Bayesian topologies. Phylogenetic relationships between closely related species were generally well resolved, and groups delineated, but the genes did not resolve deep divergences well. The phylogenies indicated strongly that Octopus is not monophyletic, but several monophyletic groups were identified within the genus. It is therefore clear that octopodid systematics requires major revision.

  12. A "Mimic Octopus" in the Atlantic: Flatfish mimicry and camouflage by Macrotritopus defilippi.

    PubMed

    Hanlon, Roger T; Watson, Anya C; Barbosa, Alexandra

    2010-02-01

    The sand-dwelling octopus Macrotritopus defilippi was filmed or photographed in five Caribbean locations mimicking the swimming behavior (posture, style, speed, duration) and coloration of the common, sand-dwelling flounder Bothus lunatus. Each species was exceptionally well camouflaged when stationary, and details of camouflaging techniques are described for M. defilippi. Octopuses implemented flounder mimicry only during swimming, when their movement would give away camouflage in this open sandy habitat. Thus, both camouflage and fish mimicry were used by the octopuses as a primary defense against visual predators. This is the first documentation of flounder mimicry by an Atlantic octopus, and only the fourth convincing case of mimicry for cephalopods, a taxon renowned for its polyphenism that is implemented mainly by neurally controlled skin patterning, but also-as shown here-by their soft flexible bodies.

  13. Arm injury produces long-term behavioral and neural hypersensitivity in octopus.

    PubMed

    Alupay, Jean S; Hadjisolomou, Stavros P; Crook, Robyn J

    2014-01-13

    Cephalopod molluscs are the most neurally and behaviorally complex invertebrates, with brains rivaling those of some vertebrates in size and complexity. This has fostered the opinion that cephalopods, particularly octopuses, may experience vertebrate-like pain when injured. However, it is not known whether octopuses possess nociceptors or if their somatic sensory neurons exhibit sensitization after injury. Here we show that the octopus Abdopus aculeatus expresses nocifensive behaviors including arm autotomy, and displays marked neural hyperexcitability both in injured and uninjured arms for at least 24h after injury. These findings do not demonstrate that octopuses experience pain-like states; instead they add to the minimal existing literature on how cephalopods receive, process, and integrate noxious sensory information, potentially informing and refining regulations governing use of cephalopods in scientific research.

  14. Arm injury produces long-term behavioral and neural hypersensitivity in octopus.

    PubMed

    Alupay, Jean S; Hadjisolomou, Stavros P; Crook, Robyn J

    2014-01-13

    Cephalopod molluscs are the most neurally and behaviorally complex invertebrates, with brains rivaling those of some vertebrates in size and complexity. This has fostered the opinion that cephalopods, particularly octopuses, may experience vertebrate-like pain when injured. However, it is not known whether octopuses possess nociceptors or if their somatic sensory neurons exhibit sensitization after injury. Here we show that the octopus Abdopus aculeatus expresses nocifensive behaviors including arm autotomy, and displays marked neural hyperexcitability both in injured and uninjured arms for at least 24h after injury. These findings do not demonstrate that octopuses experience pain-like states; instead they add to the minimal existing literature on how cephalopods receive, process, and integrate noxious sensory information, potentially informing and refining regulations governing use of cephalopods in scientific research. PMID:24239646

  15. Sperm-attractant peptide influences the spermatozoa swimming behavior in internal fertilization in Octopus vulgaris.

    PubMed

    De Lisa, Emilia; Salzano, Anna Maria; Moccia, Francesco; Scaloni, Andrea; Di Cosmo, Anna

    2013-06-15

    Marine invertebrates exhibit both chemokinesis and chemotaxis phenomena, induced in most cases by the release of water-borne peptides or pheromones. In mollusks, several peptides released during egg-laying improve both male attraction and mating. Unlike other cephalopods, Octopus vulgaris adopts an indirect internal fertilization strategy. We here report on the identification and characterization of a chemoattractant peptide isolated from mature eggs of octopus females. Using two-chamber and time-lapse microscopy assays, we demonstrate that this bioactive peptide is able to increase sperm motility and induce chemotaxis by changing the octopus spermatozoa swimming behavior in a dose-dependent manner. We also provide evidence that chemotaxis in the octopus requires the presence of extracellular calcium and membrane protein phophorylation at tyrosine. This study is the first report on a sperm-activating factor in a non-free-spawning marine animal.

  16. A "Mimic Octopus" in the Atlantic: Flatfish mimicry and camouflage by Macrotritopus defilippi.

    PubMed

    Hanlon, Roger T; Watson, Anya C; Barbosa, Alexandra

    2010-02-01

    The sand-dwelling octopus Macrotritopus defilippi was filmed or photographed in five Caribbean locations mimicking the swimming behavior (posture, style, speed, duration) and coloration of the common, sand-dwelling flounder Bothus lunatus. Each species was exceptionally well camouflaged when stationary, and details of camouflaging techniques are described for M. defilippi. Octopuses implemented flounder mimicry only during swimming, when their movement would give away camouflage in this open sandy habitat. Thus, both camouflage and fish mimicry were used by the octopuses as a primary defense against visual predators. This is the first documentation of flounder mimicry by an Atlantic octopus, and only the fourth convincing case of mimicry for cephalopods, a taxon renowned for its polyphenism that is implemented mainly by neurally controlled skin patterning, but also-as shown here-by their soft flexible bodies. PMID:20203250

  17. Camouflaging in a Complex Environment—Octopuses Use Specific Features of Their Surroundings for Background Matching

    PubMed Central

    Josef, Noam; Amodio, Piero; Fiorito, Graziano; Shashar, Nadav

    2012-01-01

    Living under intense predation pressure, octopuses evolved an effective and impressive camouflaging ability that exploits features of their surroundings to enable them to “blend in.” To achieve such background matching, an animal may use general resemblance and reproduce characteristics of its entire surroundings, or it may imitate a specific object in its immediate environment. Using image analysis algorithms, we examined correlations between octopuses and their backgrounds. Field experiments show that when camouflaging, Octopus cyanea and O. vulgaris base their body patterns on selected features of nearby objects rather than attempting to match a large field of view. Such an approach enables the octopus to camouflage in partly occluded environments and to solve the problem of differences in appearance as a function of the viewing inclination of the observer. PMID:22649542

  18. Results of a new OCTOPUS'' ECR ion source at 6. 4 GHz

    SciTech Connect

    Dupont, C.; Jongen, Y. ); Arakawa, K.; Yokota, W. ); Satoh, T.; Tachikawa, T. )

    1990-01-01

    The first OCTOPUS electron cyclstron resonance (ECR) multicharged heavy ion source was built in 1985 at the Centre de Recherches du Cyclotron of the University of Louvain (Belgium). This first source used an ECR frequency of 14.3 GHz in the injector stage and 8.5 GHz in the main confinement stage. A new OCTOPUS source has now been built for a new cyclotron to be installed at the Japan Atomic Energy Research Institute (JAERI). The design of this new OCTOPUS source is identical to the first OCTOPUS source, but uses an ECR frequency of 6.4 GHz in the main confinement stage. The experimental results are described, and a comparison is made between the two sources. However, the available data does not allow any clear conclusion to be drawn on frequency scaling.

  19. Self-recognition mechanism between skin and suckers prevents octopus arms from interfering with each other.

    PubMed

    Nesher, Nir; Levy, Guy; Grasso, Frank W; Hochner, Binyamin

    2014-06-01

    Controlling movements of flexible arms is a challenging task for the octopus because of the virtually infinite number of degrees of freedom (DOFs) [1, 2]. Octopuses simplify this control by using stereotypical motion patterns that reduce the DOFs, in the control space, to a workable few [2]. These movements are triggered by the brain and are generated by motor programs embedded in the peripheral neuromuscular system of the arm [3-5]. The hundreds of suckers along each arm have a tendency to stick to almost any object they contact [6-9]. The existence of this reflex could pose significant problems with unplanned interactions between the arms if not appropriately managed. This problem is likely to be accentuated because it is accepted that octopuses are "not aware of their arms" [10-14]. Here we report of a self-recognition mechanism that has a novel role in motor control, restraining the arms from interfering with each other. We show that the suckers of amputated arms never attach to octopus skin because a chemical in the skin inhibits the attachment reflex of the suckers. The peripheral mechanism appears to be overridden by central control because, in contrast to amputated arms, behaving octopuses sometime grab amputated arms. Surprisingly, octopuses seem to identify their own amputated arms, as they treat arms of other octopuses like food more often than their own. This self-recognition mechanism is a novel peripheral component in the embodied organization of the adaptive interactions between the octopus's brain, body, and environment [15, 16].

  20. Aldehyde dehydrogenase-derived omega-crystallins of squid and octopus. Specialization for lens expression.

    PubMed

    Zinovieva, R D; Tomarev, S I; Piatigorsky, J

    1993-05-25

    omega-Crystallin of the octopus lens is related to aldehyde dehydrogenases (ALDH) of vertebrates (Tomarev, S. I., Zinovieva, R. D., and Piatigorsky, J. (1991) J. Biol. Chem. 266, 24226-24231) and ALDH1/eta-crystallin of elephant shrews (Wistow, G., and Kim, H. (1991) J. Mol. Evol. 32, 262-269). Only very low amounts of omega-crystallin are present in the squid lens. Here, we have cloned omega-crystallin cDNAs of the octopus (Octopus dofleini) and squid (Ommastrephes sloani pacificus) lenses. The deduced amino acid sequences of omega-crystallin from these species are 78% identical to each other, 56-58% identical to cytoplasmic ALDH1 and mitochondrial ALDH2 of vertebrates (which are 66-68% identical to each other), and 40% identical to Escherichia coli and spinach ALDHs. These data are consistent with the idea that the ALDH1/ALDH2 gene duplication in vertebrates occurred after divergence of cephalopods from the line giving rise to vertebrates, but before the separation of squid and octopus. Southern blot hybridization indicated that omega-crystallin is encoded by few genes (possibly just one) in octopus and squid. Northern blot hybridization revealed two bands (2.7 and 9.0 kilobases) of omega-crystallin RNA in the octopus lens and one band (4.2 kilobases) in the squid lens; omega-crystallin RNAs were undetectable in numerous non-lens tissues of octopus and squid, suggesting lens-specific expression of this gene(s). Finally, extracts of the octopus lens had no detectable ALDH activity using different substrates, consistent with omega-crystallin having no enzymatic activity. Taken together, our results suggest that omega-crystallin evolved by duplication of an ancestral gene encoding ALDH and subsequently specialized for refraction in the transparent lens while losing ALDH activity and expression in other tissues. PMID:7684383

  1. Self-recognition mechanism between skin and suckers prevents octopus arms from interfering with each other.

    PubMed

    Nesher, Nir; Levy, Guy; Grasso, Frank W; Hochner, Binyamin

    2014-06-01

    Controlling movements of flexible arms is a challenging task for the octopus because of the virtually infinite number of degrees of freedom (DOFs) [1, 2]. Octopuses simplify this control by using stereotypical motion patterns that reduce the DOFs, in the control space, to a workable few [2]. These movements are triggered by the brain and are generated by motor programs embedded in the peripheral neuromuscular system of the arm [3-5]. The hundreds of suckers along each arm have a tendency to stick to almost any object they contact [6-9]. The existence of this reflex could pose significant problems with unplanned interactions between the arms if not appropriately managed. This problem is likely to be accentuated because it is accepted that octopuses are "not aware of their arms" [10-14]. Here we report of a self-recognition mechanism that has a novel role in motor control, restraining the arms from interfering with each other. We show that the suckers of amputated arms never attach to octopus skin because a chemical in the skin inhibits the attachment reflex of the suckers. The peripheral mechanism appears to be overridden by central control because, in contrast to amputated arms, behaving octopuses sometime grab amputated arms. Surprisingly, octopuses seem to identify their own amputated arms, as they treat arms of other octopuses like food more often than their own. This self-recognition mechanism is a novel peripheral component in the embodied organization of the adaptive interactions between the octopus's brain, body, and environment [15, 16]. PMID:24835454

  2. Lack of effect of tetrodotoxin and of an extract from the posterior salivary gland of the blue-ringed octopus following injection into the octopus and following application to its brachial nerve.

    PubMed

    Flachsenberger, W; Kerr, D I

    1985-01-01

    Lack of effect of tetrodotoxin and of an extract from the posterior salivary gland of the blue-ringed octopus following injection into the octopus and following application to its brachial nerve. Toxicon 23, 997-999, 1985. Injections of the blue-ringed octopus salivary gland extract and tetrodotoxin into the blue-ringed octopus have no ill-effect on the animals. Similarly, in vitro nerve preparations from the animal were not affected by these materials although they are both extremely potent on bioelectrically excitable preparations from other species. PMID:3006286

  3. Octopus vulgaris uses visual information to determine the location of its arm.

    PubMed

    Gutnick, Tamar; Byrne, Ruth A; Hochner, Binyamin; Kuba, Michael

    2011-03-22

    Octopuses are intelligent, soft-bodied animals with keen senses that perform reliably in a variety of visual and tactile learning tasks. However, researchers have found them disappointing in that they consistently fail in operant tasks that require them to combine central nervous system reward information with visual and peripheral knowledge of the location of their arms. Wells claimed that in order to filter and integrate an abundance of multisensory inputs that might inform the animal of the position of a single arm, octopuses would need an exceptional computing mechanism, and "There is no evidence that such a system exists in Octopus, or in any other soft bodied animal." Recent electrophysiological experiments, which found no clear somatotopic organization in the higher motor centers, support this claim. We developed a three-choice maze that required an octopus to use a single arm to reach a visually marked goal compartment. Using this operant task, we show for the first time that Octopus vulgaris is capable of guiding a single arm in a complex movement to a location. Thus, we claim that octopuses can combine peripheral arm location information with visual input to control goal-directed complex movements.

  4. The use of artificial crabs for testing predatory behavior and health in the octopus.

    PubMed

    Amodio, Piero; Andrews, Paul; Salemme, Marinella; Ponte, Giovanna; Fiorito, Graziano

    2014-01-01

    The willingness of the cephalopod mollusc Octopus vulgaris to attack a live crab is traditionally used as a method to assess the overall health and welfare of octopuses in the laboratory. This method requires placing a crab in the home tank of an animal, measuring the time (latency) taken for the octopus to initiate an attack and withdrawing the crab immediately prior to capture. The same crab is commonly used to assess multiple octopuses as part of daily welfare assessment. Growing concern for the welfare of crustaceans and a review of all laboratory practices for the care and welfare of cephalopods following the inclusion of this taxon in 2010/63/EU prompted a study of the utility of an artificial crab to replace a live crab in the assessment of octopus health. On consecutive days O. vulgaris (N=21) were presented with a live, a dead or an artificial crab, and the latency to attack measured. Despite differences in the predatory performance towards the three different crab alternatives, octopuses readily attacked the artificial (and the dead) crab, showing that they can generalize and respond appropriately towards artificial prey. Researchers should consider using an artificial crab to replace the use of a live crab as part of the routine health assessment of O. vulgaris.

  5. The use of artificial crabs for testing predatory behavior and health in the octopus.

    PubMed

    Amodio, Piero; Andrews, Paul; Salemme, Marinella; Ponte, Giovanna; Fiorito, Graziano

    2014-01-01

    The willingness of the cephalopod mollusc Octopus vulgaris to attack a live crab is traditionally used as a method to assess the overall health and welfare of octopuses in the laboratory. This method requires placing a crab in the home tank of an animal, measuring the time (latency) taken for the octopus to initiate an attack and withdrawing the crab immediately prior to capture. The same crab is commonly used to assess multiple octopuses as part of daily welfare assessment. Growing concern for the welfare of crustaceans and a review of all laboratory practices for the care and welfare of cephalopods following the inclusion of this taxon in 2010/63/EU prompted a study of the utility of an artificial crab to replace a live crab in the assessment of octopus health. On consecutive days O. vulgaris (N=21) were presented with a live, a dead or an artificial crab, and the latency to attack measured. Despite differences in the predatory performance towards the three different crab alternatives, octopuses readily attacked the artificial (and the dead) crab, showing that they can generalize and respond appropriately towards artificial prey. Researchers should consider using an artificial crab to replace the use of a live crab as part of the routine health assessment of O. vulgaris. PMID:24919978

  6. Octopus vulgaris uses visual information to determine the location of its arm.

    PubMed

    Gutnick, Tamar; Byrne, Ruth A; Hochner, Binyamin; Kuba, Michael

    2011-03-22

    Octopuses are intelligent, soft-bodied animals with keen senses that perform reliably in a variety of visual and tactile learning tasks. However, researchers have found them disappointing in that they consistently fail in operant tasks that require them to combine central nervous system reward information with visual and peripheral knowledge of the location of their arms. Wells claimed that in order to filter and integrate an abundance of multisensory inputs that might inform the animal of the position of a single arm, octopuses would need an exceptional computing mechanism, and "There is no evidence that such a system exists in Octopus, or in any other soft bodied animal." Recent electrophysiological experiments, which found no clear somatotopic organization in the higher motor centers, support this claim. We developed a three-choice maze that required an octopus to use a single arm to reach a visually marked goal compartment. Using this operant task, we show for the first time that Octopus vulgaris is capable of guiding a single arm in a complex movement to a location. Thus, we claim that octopuses can combine peripheral arm location information with visual input to control goal-directed complex movements. PMID:21396818

  7. Application of DNA Barcoding for Controlling of the Species from Octopus Genus

    PubMed Central

    Debenedetti, Francesco; Dalmasso, Alessandra; Bottero, Maria Teresa; Gilli, Maurizio; Gili, Stefano; Tepedino, Valentina

    2014-01-01

    The DNA barcoding proposes the use of a particular sequence from a single genomic region as the base for an identifying system capable to determine all animal species. This methodology comprises the analysis of a 655 base-pair region from the mithocondrial cytochrome C oxidase gene (COI). Its application in the species identification of fishery products has been very promising. However, in the last years some doubts about its usage have emerged. In this work, we make use of the DNA barcoding for the identification of some of the octopus species with higher commercial interest (Octopus membranaceus, Octopus vulgaris, Octopus aegina, Octopus cyanea) focusing the attention on the reliability and completeness of the available information on the databases. The study looked over 51 individuals apparently belonging to the Octopus genus. For the identification of O.aegina, O.cyanea, O.vulgaris species no particular problems were found. On the other hand, most of the samples of O.membranaceus, though they clearly presented the morphological characteristics of the species, were not identified with the biomolecular analyses. PMID:27800370

  8. Oxidation of Octopus vulgaris hemocyanin by nitrogen oxides

    SciTech Connect

    Salvato, B.; Giacometti, G.M.; Beltramini, M.; Zilio, F.; Giacometti, G.; Magliozzo, R.S.; Peisach, J.

    1989-01-24

    The reaction of Octopus vulgaris hemocyanin with nitrite was studied under a variety of conditions in which the green half-met derivative is formed. Analytical evidence shows that the amount of chemically detectable nitrite in various samples of the derivative is not proportional to the cupric copper detected by EPR. The kinetics of oxidation of hemocyanin as a function of protein concentration and pH, in the presence of nitrite and ascorbate, is consistent with a scheme in which NO/sub 2/ is the reactive oxidant. We suggest that the green half-methemocyanin contains a metal center with one cuprous and one cupric copper without an exogenous nitrogen oxide ligand.

  9. Selective effects of an octopus toxin on action potentials

    PubMed Central

    Dulhunty, Angela; Gage, Peter W.

    1971-01-01

    1. A lethal, water soluble toxin (Maculotoxin, MTX) with a molecular weight less than 540, can be extracted from the salivary glands of an octopus (Hapalochlaena maculosa). 2. MTX blocks action potentials in sartorius muscle fibres of toads without affecting the membrane potential. Delayed rectification is not inhibited by the toxin. 3. At low concentrations (10-6-10-5 g/ml.) MTX blocks action potentials only after a certain number have been elicited. The number of action potentials, which can be defined accurately, depends on the concentration of MTX and the concentration of sodium ions in the extracellular solution. 4. The toxin has no post-synaptic effect at the neuromuscular junction and it is concluded that it blocks neuromuscular transmission by inhibiting action potentials in motor nerve terminals. PMID:4330930

  10. Comparative morphology of changeable skin papillae in octopus and cuttlefish.

    PubMed

    Allen, Justine J; Bell, George R R; Kuzirian, Alan M; Velankar, Sachin S; Hanlon, Roger T

    2014-04-01

    A major component of cephalopod adaptive camouflage behavior has rarely been studied: their ability to change the three-dimensionality of their skin by morphing their malleable dermal papillae. Recent work has established that simple, conical papillae in cuttlefish (Sepia officinalis) function as muscular hydrostats; that is, the muscles that extend a papilla also provide its structural support. We used brightfield and scanning electron microscopy to investigate and compare the functional morphology of nine types of papillae of different shapes, sizes and complexity in six species: S. officinalis small dorsal papillae, Octopus vulgaris small dorsal and ventral eye papillae, Macrotritopus defilippi dorsal eye papillae, Abdopus aculeatus major mantle papillae, O. bimaculoides arm, minor mantle, and dorsal eye papillae, and S. apama face ridge papillae. Most papillae have two sets of muscles responsible for extension: circular dermal erector muscles arranged in a concentric pattern to lift the papilla away from the body surface and horizontal dermal erector muscles to pull the papilla's perimeter toward its core and determine shape. A third set of muscles, retractors, appears to be responsible for pulling a papilla's apex down toward the body surface while stretching out its base. Connective tissue infiltrated with mucopolysaccharides assists with structural support. S. apama face ridge papillae are different: the contraction of erector muscles perpendicular to the ridge causes overlying tissues to buckle. In this case, mucopolysaccharide-rich connective tissue provides structural support. These six species possess changeable papillae that are diverse in size and shape, yet with one exception they share somewhat similar functional morphologies. Future research on papilla morphology, biomechanics and neural control in the many unexamined species of octopus and cuttlefish may uncover new principles of actuation in soft, flexible tissue. PMID:24741712

  11. Comparative morphology of changeable skin papillae in octopus and cuttlefish.

    PubMed

    Allen, Justine J; Bell, George R R; Kuzirian, Alan M; Velankar, Sachin S; Hanlon, Roger T

    2014-04-01

    A major component of cephalopod adaptive camouflage behavior has rarely been studied: their ability to change the three-dimensionality of their skin by morphing their malleable dermal papillae. Recent work has established that simple, conical papillae in cuttlefish (Sepia officinalis) function as muscular hydrostats; that is, the muscles that extend a papilla also provide its structural support. We used brightfield and scanning electron microscopy to investigate and compare the functional morphology of nine types of papillae of different shapes, sizes and complexity in six species: S. officinalis small dorsal papillae, Octopus vulgaris small dorsal and ventral eye papillae, Macrotritopus defilippi dorsal eye papillae, Abdopus aculeatus major mantle papillae, O. bimaculoides arm, minor mantle, and dorsal eye papillae, and S. apama face ridge papillae. Most papillae have two sets of muscles responsible for extension: circular dermal erector muscles arranged in a concentric pattern to lift the papilla away from the body surface and horizontal dermal erector muscles to pull the papilla's perimeter toward its core and determine shape. A third set of muscles, retractors, appears to be responsible for pulling a papilla's apex down toward the body surface while stretching out its base. Connective tissue infiltrated with mucopolysaccharides assists with structural support. S. apama face ridge papillae are different: the contraction of erector muscles perpendicular to the ridge causes overlying tissues to buckle. In this case, mucopolysaccharide-rich connective tissue provides structural support. These six species possess changeable papillae that are diverse in size and shape, yet with one exception they share somewhat similar functional morphologies. Future research on papilla morphology, biomechanics and neural control in the many unexamined species of octopus and cuttlefish may uncover new principles of actuation in soft, flexible tissue.

  12. Beak measurements of octopus ( Octopus variabilis) in Jiaozhou Bay and their use in size and biomass estimation

    NASA Astrophysics Data System (ADS)

    Xue, Ying; Ren, Yiping; Meng, Wenrong; Li, Long; Mao, Xia; Han, Dongyan; Ma, Qiuyun

    2013-09-01

    Cephalopods play key roles in global marine ecosystems as both predators and preys. Regressive estimation of original size and weight of cephalopod from beak measurements is a powerful tool of interrogating the feeding ecology of predators at higher trophic levels. In this study, regressive relationships among beak measurements and body length and weight were determined for an octopus species ( Octopus variabilis), an important endemic cephalopod species in the northwest Pacific Ocean. A total of 193 individuals (63 males and 130 females) were collected at a monthly interval from Jiaozhou Bay, China. Regressive relationships among 6 beak measurements (upper hood length, UHL; upper crest length, UCL; lower hood length, LHL; lower crest length, LCL; and upper and lower beak weights) and mantle length (ML), total length (TL) and body weight (W) were determined. Results showed that the relationships between beak size and TL and beak size and ML were linearly regressive, while those between beak size and W fitted a power function model. LHL and UCL were the most useful measurements for estimating the size and biomass of O. variabilis. The relationships among beak measurements and body length (either ML or TL) were not significantly different between two sexes; while those among several beak measurements (UHL, LHL and LBW) and body weight (W) were sexually different. Since male individuals of this species have a slightly greater body weight distribution than female individuals, the body weight was not an appropriate measurement for estimating size and biomass, especially when the sex of individuals in the stomachs of predators was unknown. These relationships provided essential information for future use in size and biomass estimation of O. variabilis, as well as the estimation of predator/prey size ratios in the diet of top predators.

  13. Cryo-scanning electron microscopy investigation of the Octopus Vulgaris arm structures for the design of an octopus-like arm artefact.

    PubMed

    Minnocci, Antonio; Cianchetti, Matteo; Mazzolai, Barbara; Sebastiani, Luca; Laschi, Cecilia

    2015-12-01

    Octopus vulgaris is a cephalopod of the Octopodidae family. It has four pairs of arms and two rows of suckers which perform many functions, including bending and elongation. For this reason the octopus was chosen as model to develop a new generation of soft-body robots. In order to explain some of the fine structures of the octopus arm in relation to its specific ability, we examined the external and internal structures of O. vulgaris arms in a frozen-hydrated state using cryo-scanning electron microscopy. The arms showed skin with a very complex design that is useful to elongation, and a pore pattern distribution on their surface which is functional to cutaneous oxygen uptake. The analysis of freeze-fractured frozen-hydrated arm samples allowed us to describe the developmental differences in the relative proportion of the areas of axial nerve cord, intrinsic and extrinsic musculature, in relation to the growth of the arms and of the increase in functional capability. In the suckers, we analyzed the shedding mechanisms in the outer part of the infundibulum and described the outer and inner characteristics of the denticles, showing in detail their pore system, which is fundamental for their ability to explore the environment. These results are discussed by considering their possible application in the design of new octopus-like artefacts, which will be able to take advantage of some of these ultrastructure characteristics and achieve advanced bioinspired functionalities.

  14. Cryo-scanning electron microscopy investigation of the Octopus Vulgaris arm structures for the design of an octopus-like arm artefact.

    PubMed

    Minnocci, Antonio; Cianchetti, Matteo; Mazzolai, Barbara; Sebastiani, Luca; Laschi, Cecilia

    2015-12-01

    Octopus vulgaris is a cephalopod of the Octopodidae family. It has four pairs of arms and two rows of suckers which perform many functions, including bending and elongation. For this reason the octopus was chosen as model to develop a new generation of soft-body robots. In order to explain some of the fine structures of the octopus arm in relation to its specific ability, we examined the external and internal structures of O. vulgaris arms in a frozen-hydrated state using cryo-scanning electron microscopy. The arms showed skin with a very complex design that is useful to elongation, and a pore pattern distribution on their surface which is functional to cutaneous oxygen uptake. The analysis of freeze-fractured frozen-hydrated arm samples allowed us to describe the developmental differences in the relative proportion of the areas of axial nerve cord, intrinsic and extrinsic musculature, in relation to the growth of the arms and of the increase in functional capability. In the suckers, we analyzed the shedding mechanisms in the outer part of the infundibulum and described the outer and inner characteristics of the denticles, showing in detail their pore system, which is fundamental for their ability to explore the environment. These results are discussed by considering their possible application in the design of new octopus-like artefacts, which will be able to take advantage of some of these ultrastructure characteristics and achieve advanced bioinspired functionalities. PMID:26515907

  15. 76 FR 66655 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod and Octopus in the Bering Sea...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-27

    ... established by the final 2011 and 2012 harvest specifications for groundfish in the BSAI (76 FR 11139, March 1, 2011). NMFS closed directed fishing for octopus on January 13, 2011 (76 FR 3044, January 19, 2011) and prohibited retention of octopus on September 1, 2011 (76 FR 55276, September 7, 2011). As of October 15,...

  16. Soft robotic arm inspired by the octopus: I. From biological functions to artificial requirements.

    PubMed

    Margheri, L; Laschi, C; Mazzolai, B

    2012-06-01

    Octopuses are molluscs that belong to the group Cephalopoda. They lack joints and rigid links, and as a result, their arms possess virtually limitless freedom of movement. These flexible appendages exhibit peculiar biomechanical features such as stiffness control, compliance, and high flexibility and dexterity. Studying the capabilities of the octopus arm is a complex task that presents a challenge for both biologists and roboticists, the latter of whom draw inspiration from the octopus in designing novel technologies within soft robotics. With this idea in mind, in this study, we used new, purposively developed methods of analysing the octopus arm in vivo to create new biologically inspired design concepts. Our measurements showed that the octopus arm can elongate by 70% in tandem with a 23% diameter reduction and exhibits an average pulling force of 40 N. The arm also exhibited a 20% mean shortening at a rate of 17.1 mm s(-1) and a longitudinal stiffening rate as high as 2 N (mm s)(-1). Using histology and ultrasounds, we investigated the functional morphology of the internal tissues, including the sinusoidal arrangement of the nerve cord and the local insertion points of the longitudinal and transverse muscle fibres. The resulting information was used to create novel design principles and specifications that can in turn be used in developing a new soft robotic arm.

  17. The packaging problem: bivalve prey selection and prey entry techniques of the octopus Enteroctopus dofleini.

    PubMed

    Anderson, Roland C; Mather, Jennifer A

    2007-08-01

    Many predators face a complex step of prey preparation before consumption. Octopuses faced with bivalve prey use several techniques to penetrate the shells to gain access to the meat inside. When given prey of mussels Mytilus trossulus, Manila clams Venerupis philippinarum, and littleneck clams Protothaca staminea, Enteroctopus dofleini solved the problem differently. They pulled apart V. philippinarum and M. trossulus, which had the thinnest shells and the least pulling resistance. P. staminea were eaten after the shells had been chipped or had been penetrated by drilling, presumably to inject a toxin. Likely because of these differences, octopuses consumed more V. philippinarum and M. trossulus than P. staminea when the mollusks were given to them either 1 species at a time or all together. However, when the shells were separated and the penetration problem removed, the octopuses predominantly chose P. staminea and nearly ignored M. trossulus. When V. philippinarum were wired shut, octopuses switched techniques. These results emphasize that octopuses can learn on the basis of nonvisual information and monitor their body position to carry out feeding actions.

  18. The packaging problem: bivalve prey selection and prey entry techniques of the octopus Enteroctopus dofleini.

    PubMed

    Anderson, Roland C; Mather, Jennifer A

    2007-08-01

    Many predators face a complex step of prey preparation before consumption. Octopuses faced with bivalve prey use several techniques to penetrate the shells to gain access to the meat inside. When given prey of mussels Mytilus trossulus, Manila clams Venerupis philippinarum, and littleneck clams Protothaca staminea, Enteroctopus dofleini solved the problem differently. They pulled apart V. philippinarum and M. trossulus, which had the thinnest shells and the least pulling resistance. P. staminea were eaten after the shells had been chipped or had been penetrated by drilling, presumably to inject a toxin. Likely because of these differences, octopuses consumed more V. philippinarum and M. trossulus than P. staminea when the mollusks were given to them either 1 species at a time or all together. However, when the shells were separated and the penetration problem removed, the octopuses predominantly chose P. staminea and nearly ignored M. trossulus. When V. philippinarum were wired shut, octopuses switched techniques. These results emphasize that octopuses can learn on the basis of nonvisual information and monitor their body position to carry out feeding actions. PMID:17696656

  19. Unveiling the morphology of the acetabulum in octopus suckers and its role in attachment

    PubMed Central

    Tramacere, Francesca; Pugno, Nicola M.; Kuba, Michael J.; Mazzolai, Barbara

    2015-01-01

    In recent years, the attachment mechanism of the octopus sucker has attracted the interest of scientists from different research areas, including biology, engineering, medicine and robotics. From a technological perspective, the main goal is to identify the underlying mechanisms involved in sucker attachment for use in the development of new generations of artificial devices and materials. Recently, the understanding of the morphology of the sucker has been significantly improved; however, the mechanisms that allow attachment remain largely unknown. In this work, we present new anatomical findings: specifically, a protuberance in the acetabular roof in five different octopus species; previously, this protuberance was identified by the authors in Octopus vulgaris. Moreover, we discuss the role of the protuberance and other anatomical structures in attachment with minimal energy consumption. PMID:25657834

  20. Toxic exposure to ethylene dibromide and mercuric chloride: effects on laboratory-reared octopuses.

    PubMed

    Adams, P M; Hanlon, R T; Forsythe, J W

    1988-01-01

    The effects of acute and chronic exposure to either ethylene dibromide (EDB) or mercuric chloride (MC) were studied in laboratory-reared Octopus joubini, O. maya and O. bimaculoides. The advantages of using octopuses were that the responses were immediate, highly visible and sensitive. All species demonstrated signs of toxicity to acute and chronic exposure to EDB and to MC. A dosage-sensitive relationship for the loss and subsequent recovery of locomotor response and of chromatophore expansion was found for each species after acute exposure. For each species the LC50 for chronic exposure occurred within 12 hr at 100 mg/l for EDB and within 3 hr at 1,000 mg/l for MC. This study demonstrated the potential usefulness of laboratory-reared octopuses in evaluating the toxicity of marine environmental pollutants.

  1. [Substrate-inhibitory analysis of monoamine oxidase from hepatopancreas of the octopus Bathypolypus arcticus].

    PubMed

    Basova, I N; Iagodina, O V

    2012-01-01

    Study of the substrate-inhibitory specificity of mitochondrial monoamine oxidase (MAO) of hepatopancreas of the octopus Bathypolypus arcticus revealed distinctive peculiarities of catalytic properties of this enzyme. The studied enzyme, on one hand, like the classic MAO of homoiothermal animals, is able to deaminate tyramine, serotonin, benzylamine, tryptamine, beta-phenylethylamine, while, on the other hand, deaminates histamine and does not deaminate putrescine--classic substrates of diamine oxidase (DAO). Results of the substrate-inhibitory analysis with use of chlorgiline and deprenyl are indirect proofs of the existence in the octopus hepatopancreas of one molecular MAO form. Semicarbazide and pyronine G turned out to be weak irreversible inhibitors, four derivatives of acridine--irreversible inhibitors of the intermediate effectiveness with respect to the octopus hepatopancreas MAO; specificity of action of inhibitors at deamination of different substrates was equal.

  2. Concentrations of biogenic amines in fish, squid and octopus and their changes during storage.

    PubMed

    Hu, Yue; Huang, Zhiyong; Li, Jian; Yang, Hong

    2012-12-15

    The concentrations of seven biogenic amines (BA) were simultaneously determined in 74 samples of fish, squid and octopus, by the method of HPLC coupled with pre-column derivatisation. The relationship between the formation of BA in aquatic products and the growth of microbial flora during storage was also investigated. Results showed that putrescine, cadaverine, histamine and tyramine were the dominant BA in the studied samples, but the concentrations of histamine and tyramine were mostly less than 50 and 100 mgkg(-1), respectively. Freezing can effectively prevent the formation of BA, but the levels of putrescine, cadaverine, histamine and tyramine significantly increased (p<0.05) during storage at 4 and 25°C. The growth of mesophilic or psychrophilic bacteria in blue scad and octopus strongly and positively correlated with the formation of amines (such as putrescine, cadaverine, histamine and tyramine) during storage, except for histamine in octopus.

  3. Toxic exposure to ethylene dibromide and mercuric chloride: effects on laboratory-reared octopuses.

    PubMed

    Adams, P M; Hanlon, R T; Forsythe, J W

    1988-01-01

    The effects of acute and chronic exposure to either ethylene dibromide (EDB) or mercuric chloride (MC) were studied in laboratory-reared Octopus joubini, O. maya and O. bimaculoides. The advantages of using octopuses were that the responses were immediate, highly visible and sensitive. All species demonstrated signs of toxicity to acute and chronic exposure to EDB and to MC. A dosage-sensitive relationship for the loss and subsequent recovery of locomotor response and of chromatophore expansion was found for each species after acute exposure. For each species the LC50 for chronic exposure occurred within 12 hr at 100 mg/l for EDB and within 3 hr at 1,000 mg/l for MC. This study demonstrated the potential usefulness of laboratory-reared octopuses in evaluating the toxicity of marine environmental pollutants. PMID:3072470

  4. Bioactive Lipidic Extracts from Octopus (Paraoctopus limaculatus): Antimutagenicity and Antiproliferative Studies

    PubMed Central

    Moreno-Félix, Carolina; Wilson-Sánchez, Griselda; Cruz-Ramírez, Susana-Gabriela; Velázquez-Contreras, Carlos; Plascencia-Jatomea, Maribel; Acosta, Ana; Machi-Lara, Lorena; Aldana-Madrid, María-Lourdes; Ezquerra-Brauer, Josafat-Marina; Rocha-Alonzo, Fernando; Burgos-Hernández, Armando

    2013-01-01

    Fractions from an organic extract from fresh octopus (Paraoctopus limaculatus) were studied for biological activities such as antimutagenic and antiproliferative properties using Salmonella tester strains TA98 and TA100 with metabolic activation (S9) and a cancer cell line (B-cell lymphoma), respectively. A chloroform extract obtained from octopus tentacles was sequentially fractionated using thin layer chromatography (TLC), and each fraction was tested for antimutagenic and antiproliferative activities. Organic extract reduced the number of revertants caused by aflatoxin B1 showing a dose-response type of relationship. Sequential TLC fractionation of the active extracts produced several antimutagenic and/or antiproliferative fractions. Based on the results obtained, the isolated fractions obtained from octopus contain compounds with chemoprotective properties that reduce the mutagenicity of AFB1 and proliferation of cancer cell lines. PMID:23401709

  5. Reflector cells in the skin of Octopus dofleini.

    PubMed

    Brocco, S L; Cloney, R A

    1980-01-01

    The cells that form the reflecting layer beneath the chromatophore organs of the octopus are conspicuous elements of its dermal chromatic system. Each flattened, ellipsoidal reflector cell in this layer bears thousands of peripherally radiating, discoidal, reflecting lamellae. Each lamella consists of a proteinaceous reflecting platelet enveloped by the plasmalemma. The lamellae average 90 nm in thickness and have variable diameters with a maximum of about 1.7 micrometer. Sets of reflecting lamellae are organized into functional units called reflectosomes. The lamellae in each reflectosome form a parallel array - similar to a stack of coins. The average number of lamellae in a reflectosome is 11. Adjacent lamellae are uniformly separated by an extracellular gap of about 60 nm in embedded specimens. The reflectosomes are randomly disposed over the surface of the reflector cell. The observed organization of the reflectosomes is compatible with its role as a quarter-wave thin-film interference device. The alternating reflecting lamellae and intelamellar spaces constitute layers of high and low refractive indices. Using measurements of the thicknesses and refractive indices of the platelets and interlamellar spaces, we have calculated that the color of reflected light should be blue - green, as seen in vivo. The sequence of events leading to the definitive arrangement of the reflectosomes is uncertain. The reflector cells of O. dofleini are compared and contrasted with the iridophores of squid.

  6. Reflector cells in the skin of Octopus dofleini.

    PubMed

    Brocco, S L; Cloney, R A

    1980-01-01

    The cells that form the reflecting layer beneath the chromatophore organs of the octopus are conspicuous elements of its dermal chromatic system. Each flattened, ellipsoidal reflector cell in this layer bears thousands of peripherally radiating, discoidal, reflecting lamellae. Each lamella consists of a proteinaceous reflecting platelet enveloped by the plasmalemma. The lamellae average 90 nm in thickness and have variable diameters with a maximum of about 1.7 micrometer. Sets of reflecting lamellae are organized into functional units called reflectosomes. The lamellae in each reflectosome form a parallel array - similar to a stack of coins. The average number of lamellae in a reflectosome is 11. Adjacent lamellae are uniformly separated by an extracellular gap of about 60 nm in embedded specimens. The reflectosomes are randomly disposed over the surface of the reflector cell. The observed organization of the reflectosomes is compatible with its role as a quarter-wave thin-film interference device. The alternating reflecting lamellae and intelamellar spaces constitute layers of high and low refractive indices. Using measurements of the thicknesses and refractive indices of the platelets and interlamellar spaces, we have calculated that the color of reflected light should be blue - green, as seen in vivo. The sequence of events leading to the definitive arrangement of the reflectosomes is uncertain. The reflector cells of O. dofleini are compared and contrasted with the iridophores of squid. PMID:6244094

  7. Innovative use of the octopus stabilizer in the excision of a cardiac hydatid cyst.

    PubMed

    Musleh, Mohammud; Abuhussein, Nadia; Musleh, Ghassan; Waterworth, Paul

    2016-01-01

    Hydatid disease is caused through Echinococcus granulosus infection. Hydatid disease remains endemic in developing countries. The majority of cases involve the lungs or liver. We report the case of a patient diagnosed with concurrent mediastinal and cardiac cysts. In this patient, the Octopus IV cardiac stabilizer was used to rotate the heart after the excision of the mediastinal cyst, enabling the excision of a cyst adherent to left ventricle through a single median sternotomy incision. To date, there have been no reports of the application of the Octopus IV cardiac stabilizer in such a way. PMID:26921611

  8. Eye-independent, light-activated chromatophore expansion (LACE) and expression of phototransduction genes in the skin of Octopus bimaculoides.

    PubMed

    Ramirez, M Desmond; Oakley, Todd H

    2015-05-15

    Cephalopods are renowned for changing the color and pattern of their skin for both camouflage and communication. Yet, we do not fully understand how cephalopods control the pigmented chromatophore organs in their skin and change their body pattern. Although these changes primarily rely on eyesight, we found that light causes chromatophores to expand in excised pieces of Octopus bimaculoides skin. We call this behavior light-activated chromatophore expansion (or LACE). To uncover how octopus skin senses light, we used antibodies against r-opsin phototransduction proteins to identify sensory neurons that express r-opsin in the skin. We hypothesized that octopus LACE relies on the same r-opsin phototransduction cascade found in octopus eyes. By creating an action spectrum for the latency to LACE, we found that LACE occurred most quickly in response to blue light. We fit our action spectrum data to a standard opsin curve template and estimated the λmax of LACE to be 480 nm. Consistent with our hypothesis, the maximum sensitivity of the light sensors underlying LACE closely matches the known spectral sensitivity of opsin from octopus eyes. LACE in isolated preparations suggests that octopus skin is intrinsically light sensitive and that this dispersed light sense might contribute to their unique and novel patterning abilities. Finally, our data suggest that a common molecular mechanism for light detection in eyes may have been co-opted for light sensing in octopus skin and then used for LACE.

  9. Eye-independent, light-activated chromatophore expansion (LACE) and expression of phototransduction genes in the skin of Octopus bimaculoides

    PubMed Central

    Ramirez, M. Desmond; Oakley, Todd H.

    2015-01-01

    ABSTRACT Cephalopods are renowned for changing the color and pattern of their skin for both camouflage and communication. Yet, we do not fully understand how cephalopods control the pigmented chromatophore organs in their skin and change their body pattern. Although these changes primarily rely on eyesight, we found that light causes chromatophores to expand in excised pieces of Octopus bimaculoides skin. We call this behavior light-activated chromatophore expansion (or LACE). To uncover how octopus skin senses light, we used antibodies against r-opsin phototransduction proteins to identify sensory neurons that express r-opsin in the skin. We hypothesized that octopus LACE relies on the same r-opsin phototransduction cascade found in octopus eyes. By creating an action spectrum for the latency to LACE, we found that LACE occurred most quickly in response to blue light. We fit our action spectrum data to a standard opsin curve template and estimated the λmax of LACE to be 480 nm. Consistent with our hypothesis, the maximum sensitivity of the light sensors underlying LACE closely matches the known spectral sensitivity of opsin from octopus eyes. LACE in isolated preparations suggests that octopus skin is intrinsically light sensitive and that this dispersed light sense might contribute to their unique and novel patterning abilities. Finally, our data suggest that a common molecular mechanism for light detection in eyes may have been co-opted for light sensing in octopus skin and then used for LACE. PMID:25994633

  10. Eye-independent, light-activated chromatophore expansion (LACE) and expression of phototransduction genes in the skin of Octopus bimaculoides.

    PubMed

    Ramirez, M Desmond; Oakley, Todd H

    2015-05-15

    Cephalopods are renowned for changing the color and pattern of their skin for both camouflage and communication. Yet, we do not fully understand how cephalopods control the pigmented chromatophore organs in their skin and change their body pattern. Although these changes primarily rely on eyesight, we found that light causes chromatophores to expand in excised pieces of Octopus bimaculoides skin. We call this behavior light-activated chromatophore expansion (or LACE). To uncover how octopus skin senses light, we used antibodies against r-opsin phototransduction proteins to identify sensory neurons that express r-opsin in the skin. We hypothesized that octopus LACE relies on the same r-opsin phototransduction cascade found in octopus eyes. By creating an action spectrum for the latency to LACE, we found that LACE occurred most quickly in response to blue light. We fit our action spectrum data to a standard opsin curve template and estimated the λmax of LACE to be 480 nm. Consistent with our hypothesis, the maximum sensitivity of the light sensors underlying LACE closely matches the known spectral sensitivity of opsin from octopus eyes. LACE in isolated preparations suggests that octopus skin is intrinsically light sensitive and that this dispersed light sense might contribute to their unique and novel patterning abilities. Finally, our data suggest that a common molecular mechanism for light detection in eyes may have been co-opted for light sensing in octopus skin and then used for LACE. PMID:25994633

  11. Venom on ice: first insights into Antarctic octopus venoms.

    PubMed

    Undheim, E A B; Georgieva, D N; Thoen, H H; Norman, J A; Mork, J; Betzel, C; Fry, B G

    2010-11-01

    The venom of Antarctic octopus remains completely unstudied. Here, a preliminary investigation was conducted into the properties of posterior salivary gland (PSG) extracts from four Antarctica eledonine (Incirrata; Octopodidae) species (Adelieledone polymorpha, Megaleledone setebos, Pareledone aequipapillae, and Pareledone turqueti) collected from the coast off George V's Land, Antarctica. Specimens were assayed for alkaline phosphatase (ALP), acetylcholinesterase (AChE), proteolytic, phospholipase A(2) (PLA(2)), and haemolytic activities. For comparison, stomach tissue from Cirroctopus sp. (Cirrata; Cirroctopodidae) was also assayed for ALP, AChE, proteolytic and haemolytic activities. Dietary and morphological data were collected from the literature to explore the ecological importance of venom, taking an adaptive evolutionary approach. Of the incirrate species, three showed activities in all assays, while P. turqueti did not exhibit any haemolytic activity. There was evidence for cold-adaptation of ALP in all incirrates, while proteolytic activity in all except P. turqueti. Cirroctopus sp. stomach tissue extract showed ALP, AChE and some proteolytic activity. It was concluded that the AChE activity seen in the PSG extracts was possibly due to a release of household proteins, and not one of the secreted salivary toxins. Although venom undoubtedly plays an important part in prey capture and processing by Antarctica eledonines, no obvious adaptations to differences in diet or morphology were apparent from the enzymatic and haemolytic assays. However, several morphological features including enlarged PSG, small buccal mass, and small beak suggest such adaptations are present. Future studies should be conducted on several levels: Venomic, providing more detailed information on the venom compositions as well as the venom components themselves; ecological, for example application of serological or genetic methods in identifying stomach contents; and behavioural

  12. Octopus-inspired multi-arm robotic swimming.

    PubMed

    Sfakiotakis, M; Kazakidi, A; Tsakiris, D P

    2015-06-01

    The outstanding locomotor and manipulation characteristics of the octopus have recently inspired the development, by our group, of multi-functional robotic swimmers, featuring both manipulation and locomotion capabilities, which could be of significant engineering interest in underwater applications. During its little-studied arm-swimming behavior, as opposed to the better known jetting via the siphon, the animal appears to generate considerable propulsive thrust and rapid acceleration, predominantly employing movements of its arms. In this work, we capture the fundamental characteristics of the corresponding complex pattern of arm motion by a sculling profile, involving a fast power stroke and a slow recovery stroke. We investigate the propulsive capabilities of a multi-arm robotic system under various swimming gaits, namely patterns of arm coordination, which achieve the generation of forward, as well as backward, propulsion and turning. A lumped-element model of the robotic swimmer, which considers arm compliance and the interaction with the aquatic environment, was used to study the characteristics of these gaits, the effect of various kinematic parameters on propulsion, and the generation of complex trajectories. This investigation focuses on relatively high-stiffness arms. Experiments employing a compliant-body robotic prototype swimmer with eight compliant arms, all made of polyurethane, inside a water tank, successfully demonstrated this novel mode of underwater propulsion. Speeds of up to 0.26 body lengths per second (approximately 100 mm s(-1)), and propulsive forces of up to 3.5 N were achieved, with a non-dimensional cost of transport of 1.42 with all eight arms and of 0.9 with only two active arms. The experiments confirmed the computational results and verified the multi-arm maneuverability and simultaneous object grasping capability of such systems. PMID:25970151

  13. Octopus-inspired multi-arm robotic swimming.

    PubMed

    Sfakiotakis, M; Kazakidi, A; Tsakiris, D P

    2015-05-13

    The outstanding locomotor and manipulation characteristics of the octopus have recently inspired the development, by our group, of multi-functional robotic swimmers, featuring both manipulation and locomotion capabilities, which could be of significant engineering interest in underwater applications. During its little-studied arm-swimming behavior, as opposed to the better known jetting via the siphon, the animal appears to generate considerable propulsive thrust and rapid acceleration, predominantly employing movements of its arms. In this work, we capture the fundamental characteristics of the corresponding complex pattern of arm motion by a sculling profile, involving a fast power stroke and a slow recovery stroke. We investigate the propulsive capabilities of a multi-arm robotic system under various swimming gaits, namely patterns of arm coordination, which achieve the generation of forward, as well as backward, propulsion and turning. A lumped-element model of the robotic swimmer, which considers arm compliance and the interaction with the aquatic environment, was used to study the characteristics of these gaits, the effect of various kinematic parameters on propulsion, and the generation of complex trajectories. This investigation focuses on relatively high-stiffness arms. Experiments employing a compliant-body robotic prototype swimmer with eight compliant arms, all made of polyurethane, inside a water tank, successfully demonstrated this novel mode of underwater propulsion. Speeds of up to 0.26 body lengths per second (approximately 100 mm s(-1)), and propulsive forces of up to 3.5 N were achieved, with a non-dimensional cost of transport of 1.42 with all eight arms and of 0.9 with only two active arms. The experiments confirmed the computational results and verified the multi-arm maneuverability and simultaneous object grasping capability of such systems.

  14. Transcriptome Analysis of the Octopus vulgaris Central Nervous System

    PubMed Central

    Zhang, Xiang; Mao, Yong; Huang, Zixia; Qu, Meng; Chen, Jun; Ding, Shaoxiong; Hong, Jingni; Sun, Tiantian

    2012-01-01

    Background Cephalopoda are a class of Mollusca species found in all the world's oceans. They are an important model organism in neurobiology. Unfortunately, the lack of neuronal molecular sequences, such as ESTs, transcriptomic or genomic information, has limited the development of molecular neurobiology research in this unique model organism. Results With high-throughput Illumina Solexa sequencing technology, we have generated 59,859 high quality sequences from 12,918,391 paired-end reads. Using BLASTx/BLASTn, 12,227 contigs have blast hits in the Swissprot, NR protein database and NT nucleotide database with E-value cutoff 1e−5. The comparison between the Octopus vulgaris central nervous system (CNS) library and the Aplysia californica/Lymnaea stagnalis CNS ESTs library yielded 5.93%/13.45% of O. vulgaris sequences with significant matches (1e−5) using BLASTn/tBLASTx. Meanwhile the hit percentage of the recently published Schistocerca gregaria, Tilapia or Hirudo medicinalis CNS library to the O. vulgaris CNS library is 21.03%–46.19%. We constructed the Phylogenetic tree using two genes related to CNS function, Synaptotagmin-7 and Synaptophysin. Lastly, we demonstrated that O. vulgaris may have a vertebrate-like Blood-Brain Barrier based on bioinformatic analysis. Conclusion This study provides a mass of molecular information that will contribute to further molecular biology research on O. vulgaris. In our presentation of the first CNS transcriptome analysis of O. vulgaris, we hope to accelerate the study of functional molecular neurobiology and comparative evolutionary biology. PMID:22768275

  15. Egg brooding by deep-sea octopuses in the North Pacific Ocean.

    PubMed

    Voight, J R; Grehan, A J

    2000-02-01

    Videotapes made from the submersible Alvin on Baby Bare, a 2600-m-deep North Pacific basalt outcrop, and at two other deep-sea localities document that octopuses of the genera Graneledone and Benthoctopus attach their eggs to hard substrate and apparently brood them through development. The behavior of brooding females was generally similar to that of shallow-water octopuses, but the genera showed apparent differences. In addition to the high density of brooding females observed at Baby Bare, which may relate to the increased availability of exposed hard substrates for egg attachment and of prey, females are suggested to increasingly associate with hard substrates as they mature. The biology of Baby Bare may seem unduly unique because the outcrop is isolated on a sedimented plain and is among the few exposures of hard substrate other than hydrothermal vents that have been explored by submersible. On the sediment-covered ocean floor, the availability of hard substrate may strongly affect the distribution of brooding octopuses. The size and shape of boreholes in 19 of over 400 thyasirid clam shells collected from Baby Bare support the hypothesis that octopuses had preyed upon the clams.

  16. O-Crystallin, arginine kinase and ferritin from the octopus lens.

    PubMed

    Zinovieva, R D; Piatigorsky, J; Tomarev, S I

    1999-05-18

    Three proteins have been identified in the eye lens of the octopus, Octopus dofleini. A 22 kDa protein comprising 3-5% of the soluble protein of the lens is 35-43% identical to a family of phosphatidylethanolamine-binding proteins of vertebrates. Other members of this family include the immunodominant antigen of the filarial parasite, Onchocerca volvulus, putative odorant-binding proteins of Drosophila and a protein with unknown function of Caenorhabditis elegans. We have called this protein O-crystallin on the basis of its abundance in the transparent lens. O-Crystallin mRNA was detected only in the lens. Two tryptic peptides of another octopus lens protein, less abundant than O-crystallin, showed 80% identity to arginine kinase of invertebrates, a relative of creatine kinase of vertebrates. Finally, ferritin cDNA was isolated as an abundant cDNA from the octopus lens library. Northern blots showed that ferritin mRNA is not lens-specific. PMID:10350626

  17. D(--)-lactic acid and d(--)-lactate dehydrohgenase in octopus spermatozoa.

    PubMed

    Mann, T; Martin, A W; Thiersch, J B; Lutwak-Mann, C; Brooks, D E; Jones, R

    1974-08-01

    The spermatozoa of Octopus dofleini martini produce anaerobically D(-)-lactic acid and possess a very active D(-)-lactate dehydrogenase. In this respect, while resembling certain microorganisms, they differ strikingly from mammalian spermatozoa which produce L(+)-lactic acid and contain L(+)-lactate dehydrogenase. PMID:4366789

  18. Olfactory organ of Octopus vulgaris: morphology, plasticity, turnover and sensory characterization.

    PubMed

    Polese, Gianluca; Bertapelle, Carla; Di Cosmo, Anna

    2016-01-01

    The cephalopod olfactory organ was described for the first time in 1844 by von Kölliker, who was attracted to the pair of small pits of ciliated cells on each side of the head, below the eyes close to the mantle edge, in both octopuses and squids. Several functional studies have been conducted on decapods but very little is known about octopods. The morphology of the octopus olfactory system has been studied, but only to a limited extent on post-hatching specimens, and the only paper on adult octopus gives a minimal description of the olfactory organ. Here, we describe the detailed morphology of young male and female Octopus vulgaris olfactory epithelium, and using a combination of classical morphology and 3D reconstruction techniques, we propose a new classification for O. vulgaris olfactory sensory neurons. Furthermore, using specific markers such as olfactory marker protein (OMP) and proliferating cell nuclear antigen (PCNA) we have been able to identify and differentially localize both mature olfactory sensory neurons and olfactory sensory neurons involved in epithelium turnover. Taken together, our data suggest that the O. vulgaris olfactory organ is extremely plastic, capable of changing its shape and also proliferating its cells in older specimens. PMID:27069253

  19. Learning and memory in Octopus vulgaris: a case of biological plasticity.

    PubMed

    Zarrella, Ilaria; Ponte, Giovanna; Baldascino, Elena; Fiorito, Graziano

    2015-12-01

    Here we concisely summarize major aspects of the learning capabilities of the cephalopod mollusc Octopus vulgaris, a solitary living marine invertebrate. We aim to provide a backdrop against which neurobiology of these animals can be further interpreted and thus soliciting further interest for one of the most advanced members of invertebrate animals. PMID:26186237

  20. Rearing and growth of the Octopus Robsonella fontaniana (Cephalopoda: Octopodidae) from planktonic hatchlings to benthic juveniles.

    PubMed

    Uriarte, Iker; Hernández, Jorge; Dörner, Jessica; Paschke, Kurt; Farías, Ana; Crovetto, Enzo; Rosas, Carlos

    2010-04-01

    Globally, octopus larviculture is one of the challenges faced in the attempt to diversify aquaculture and achieve cephalopod farming. Currently, only juveniles of Octopus vulgaris, Octopus joubini, and Enteroctopus dofleini have been obtained at an experimental level. This is the first study to look at the characteristics of planktonic and benthic Robsonella fontaniana juveniles in an effort to analyze the morphometric changes occurring during their planktonic and benthic phases and to explore the feasibility of obtaining settlement under controlled conditions. The morphometric measurements varied exponentially over time and did not show different tendencies before and after settlement. Mantle growth in relation to total length fit a logarithmic regression, whereas arm length and eye diameter increased linearly with respect to total length throughout the entire paralarval and juvenile periods. This suggests that the size of the mantle decreases with age in proportion to the total octopus length, whereas the organs more directly involved in catching prey tend to increase in direct proportion to the total length. The present study shows that R. fontaniana can be reared from hatching through the final paralarval stage on a diet of Lithodes santolla (king crab) zoeae; after settlement, the juveniles can be reared on a diet of crab such as Petrolisthes. PMID:20413796

  1. Olfactory organ of Octopus vulgaris: morphology, plasticity, turnover and sensory characterization

    PubMed Central

    Polese, Gianluca; Bertapelle, Carla

    2016-01-01

    ABSTRACT The cephalopod olfactory organ was described for the first time in 1844 by von Kölliker, who was attracted to the pair of small pits of ciliated cells on each side of the head, below the eyes close to the mantle edge, in both octopuses and squids. Several functional studies have been conducted on decapods but very little is known about octopods. The morphology of the octopus olfactory system has been studied, but only to a limited extent on post-hatching specimens, and the only paper on adult octopus gives a minimal description of the olfactory organ. Here, we describe the detailed morphology of young male and female Octopus vulgaris olfactory epithelium, and using a combination of classical morphology and 3D reconstruction techniques, we propose a new classification for O. vulgaris olfactory sensory neurons. Furthermore, using specific markers such as olfactory marker protein (OMP) and proliferating cell nuclear antigen (PCNA) we have been able to identify and differentially localize both mature olfactory sensory neurons and olfactory sensory neurons involved in epithelium turnover. Taken together, our data suggest that the O. vulgaris olfactory organ is extremely plastic, capable of changing its shape and also proliferating its cells in older specimens. PMID:27069253

  2. OCTOPUS--A Church-Based Sex Education Program for Teens and Parents.

    ERIC Educational Resources Information Center

    Jacknik, Michele; And Others

    1984-01-01

    Describes OCTOPUS (Open Communication Regarding Teenagers or Parents Understanding of Sexuality), which was established as a forum for family discussion within a church setting. The program was designed to enhance communication skills, convey information, and help teenagers acquire appropriate morals and values. Feedback from four churches…

  3. Rearing and growth of the Octopus Robsonella fontaniana (Cephalopoda: Octopodidae) from planktonic hatchlings to benthic juveniles.

    PubMed

    Uriarte, Iker; Hernández, Jorge; Dörner, Jessica; Paschke, Kurt; Farías, Ana; Crovetto, Enzo; Rosas, Carlos

    2010-04-01

    Globally, octopus larviculture is one of the challenges faced in the attempt to diversify aquaculture and achieve cephalopod farming. Currently, only juveniles of Octopus vulgaris, Octopus joubini, and Enteroctopus dofleini have been obtained at an experimental level. This is the first study to look at the characteristics of planktonic and benthic Robsonella fontaniana juveniles in an effort to analyze the morphometric changes occurring during their planktonic and benthic phases and to explore the feasibility of obtaining settlement under controlled conditions. The morphometric measurements varied exponentially over time and did not show different tendencies before and after settlement. Mantle growth in relation to total length fit a logarithmic regression, whereas arm length and eye diameter increased linearly with respect to total length throughout the entire paralarval and juvenile periods. This suggests that the size of the mantle decreases with age in proportion to the total octopus length, whereas the organs more directly involved in catching prey tend to increase in direct proportion to the total length. The present study shows that R. fontaniana can be reared from hatching through the final paralarval stage on a diet of Lithodes santolla (king crab) zoeae; after settlement, the juveniles can be reared on a diet of crab such as Petrolisthes.

  4. Learning and memory in Octopus vulgaris: a case of biological plasticity.

    PubMed

    Zarrella, Ilaria; Ponte, Giovanna; Baldascino, Elena; Fiorito, Graziano

    2015-12-01

    Here we concisely summarize major aspects of the learning capabilities of the cephalopod mollusc Octopus vulgaris, a solitary living marine invertebrate. We aim to provide a backdrop against which neurobiology of these animals can be further interpreted and thus soliciting further interest for one of the most advanced members of invertebrate animals.

  5. Comparative molecular analysis of evolutionarily distant glyceraldehyde-3-phosphate dehydrogenase from Sardina pilchardus and Octopus vulgaris.

    PubMed

    Baibai, Tarik; Oukhattar, Laila; Mountassif, Driss; Assobhei, Omar; Serrano, Aurelio; Soukri, Abdelaziz

    2010-12-01

    The NAD(+)-dependent cytosolic glyceraldehyde-3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12), which is recognized as a key to central carbon metabolism in glycolysis and gluconeogenesis and as an important allozymic polymorphic biomarker, was purified from muscles of two marine species: the skeletal muscle of Sardina pilchardus Walbaum (Teleost, Clupeida) and the incompressible arm muscle of Octopus vulgaris (Mollusca, Cephalopoda). Comparative biochemical studies have revealed that they differ in their subunit molecular masses and in pI values. Partial cDNA sequences corresponding to an internal region of the GapC genes from Sardina and Octopus were obtained by polymerase chain reaction using degenerate primers designed from highly conserved protein motifs. Alignments of the deduced amino acid sequences were used to establish the 3D structures of the active site of two enzymes as well as the phylogenetic relationships of the sardine and octopus enzymes. These two enzymes are the first two GAPDHs characterized so far from teleost fish and cephalopod, respectively. Interestingly, phylogenetic analyses indicated that the sardina GAPDH is in a cluster with the archetypical enzymes from other vertebrates, while the octopus GAPDH comes together with other molluscan sequences in a distant basal assembly closer to bacterial and fungal orthologs, thus suggesting their different evolutionary scenarios.

  6. [Growth of Octopus maya (Mollusca: Cephalopoda) of the Yucatan coast, Mexico: a long-term analysis].

    PubMed

    Nepita Villanueva, M R; Defeo, O

    2001-03-01

    Growth of the octopus (Octopus maya) off Yucatan (Mexico) was estimated from a long-term study (seven years) by the length-based methods ELEFAN, PROJMAT and SLCA. Some 19,251 octopuses with a range of mantle length between 50 and 240 mm were sampled from commercial landings in 1983-1987, 1989 and 1992. The jackknife technique was applied to deal with uncertainty in growth estimates resulting from chance variations in sampling design. The growth index phi' was used for comparative purposes. Results differed markedly among methods: ELEFAN produced parameter estimates within the range reported in the literature, whereas PROJMAT and SLCA showed problems to converge in an optimum combination of parameters, and tended to underestimate them. Jackknife analysis revealed very low intraannual variability in phi' but high variability among years, especially when applying PROJMAT. No significant differences were found in precision parameters--percent error and coefficient of variation--among methods. Estimates of phi' derived by ELEFAN varied between 4.19 and 5.23 and agreed with those reported in the literature (between 4.25 and 4.91), whereas PROJMAT and SLCA estimates were significantly lower. We suggest the use of ELEFAN, together with jackknife, to estimate growth parameters of Octopus maya. PMID:11795175

  7. Resonance Raman studies of the HOOP modes in octopus bathorhodopsin with deuterium-labeled retinal chromophores

    SciTech Connect

    Deng, H.; Manor, D.; Weng, G.; Rath, P.; Callender, R.H. ); Koutalos, Y.; Ebrey, T. ); Gebhard, R.; Lugtenburg, J. ); Tsuda, M. )

    1991-05-07

    Resonance Raman spectra of the hydrogen out-of-plane (HOOP) vibrational modes in the retinal chromophore of octopus bathorhodopsin with deuterium label(s) along the polyene chain have been obtained. In clear contrast with bovine bathorhodopsin's HOOP modes, there are only two major HOOP bands at 887 and 940 cm{sup {minus}1} for octopus bathorhodopsin. On the basis of their isotopic shifts upon deuterium labeling, the authors have assigned the band at 887 cm{sup {minus}1} to C{sub 10}H and C{sub 14}H HOOP modes, and the band at 940 cm{sup {minus}1} to C{sub 11}H{double bond}C{sub 12}H A{sub u}-like HOOP mode. They found also that the C{sub 10}H and C{sub 14}H HOOP wags are also similar to those in the model-compound studies. However, they have found that the interaction between the C{sub 7}H and C{sub 8}H HOOP internal coordinates of the chromophore in octopus bathorhodopsin is different from that of the chromophore in solution. The twisted nature of the chromophore, semiquantitatively discussed here, likely affects the {lambda}{sub max} of the chromophore and its enthalpy. The nature of the HOOP modes of octopus bathorhodopsin differs substantially from those found in bovine bathorhodopsin.

  8. Sensory, biochemical and bacteriological properties of octopus (Cistopus indicus) stored in ice.

    PubMed

    Shalini, R; Shakila, R Jeya; Jeyasekaran, G; Jeevithan, E

    2015-10-01

    Octopus (Cistopus indicus) were examined for the changes in autolytic activity, ammoniacal nitrogen, non-protein nitrogen (NPN), total volatile base nitrogen (TVBN), free fatty acid (FFA) content, aerobic plate count (APC) and sensory quality based on Quality Index Method (QIM) during ice storage. They were sensorily acceptable up to 7 days when QIM score was 10.97 out of 16.00. Autolytic activity increased from the initial value of 174 to 619 nmoles Tyr/g/h within day 3 and later decreased. There was also an increase in NPN (34.88 to 76.16 mg %), ammoniacal nitrogen (0 to 7.30 ppm) and free fatty acid content (0.35 to 1.69 % of oleic acid) during storage. TVBN values did not correlate with the spoilage, as it increased from 28 to 145 mg% within day 5, exceeding the limit of acceptability; although total QIM score was 7.47. Aerobic plate count did not show significant change suggesting that the spoilage in octopus was not microbial. The rapid spoilage in octopus was mainly due to the release of NPN compounds following autolytic activity leading to the formation of ammoniacal nitrogen, rather than microbial spoilage. Hence, ammoniacal nitrogen can be taken as an index for spoilage of ice stored octopus. PMID:26396427

  9. Survival after severe envenomation by the blue-ringed octopus (Hapalochlaena maculosa).

    PubMed

    Walker, D G

    I report two cases of life-endangering respiratory failure after envenomation by a blue-ringed octopus (Hapalochlaena maculosa). Early and efficient support of respiratory function is vital in such cases. Cardiac asystole occurred in one patient. Both patients recovered completely after the vigorous application of routine resuscitation techniques. PMID:6669130

  10. Maculotoxin: a neurotoxin from the venom glands of the octopus Hapalochlaena maculosa identified as tetrodotoxin.

    PubMed

    Sheumack, D D; Howden, M E; Spence, I; Quinn, R J

    1978-01-13

    Maculotoxin, a potent neurotoxin isolated from the posterior salivary glands of the blue-ringed octopus. Hapalochlaena maculosa, has now been identified as tetrodotoxin. This is the first reported case in which tetrodotoxin has been found to occur in a venom. PMID:619451

  11. Molecular characterization of a KIF3B-like kinesin gene in the testis of Octopus tankahkeei (Cephalopoda, Octopus).

    PubMed

    Dang, Ran; Zhu, Jun-Quan; Tan, Fu-Qing; Wang, Wei; Zhou, Hong; Yang, Wan-Xi

    2012-05-01

    KIF3B is known for maintaining and assembling cilia and flagellum. To date, the function of KIF3B and its relationship with KIF3A during spermiogenesis in the cephalopod Octopus tankahkeei remains unknown. In the present study, we characterized a gene encoding a homologue of rat KIF3B in the O. tankahkeei testis and examined its temporal and spatial expression pattern during spermiogenesis. The cDNA of KIF3B was obtained with degenerate and RACE PCR and the distribution pattern of ot-kif3b were observed with RT-PCR. The morphological development during spermiogenesis was illustrated by histological and transmission electron microscopy and mRNA expression of ot-kif3b was observed by in situ hybridization. The 2,365 nucleotides cDNA consisted of a 102 bp 5' untranslated region (UTR), a 2,208 bp open reading frame (ORF) encoding a protein of 736 amino acids, and a 55 bp 3' UTR. Multiple alignments revealed that the putative Ot-KIF3B shared 68, 68, 69, 68, and 67% identity with that of Homo sapiens, Mus musculus, Gallus gallus, Danio rerio, and Xenopus laevis, respectively, along with high identities with Ot-KIF3A in fundamental structures. Ot-kif3b transcripts appeared gradually in early spermatids, increased in intermediate spermatids and maximized in drastically remodeled and final spermatids. The kif3b gene is identified and its expression pattern is demonstrated for the first time in O. tankahkeei. Compared to ot-kif3a reported by our laboratory before, our data suggested that the putative heterodimeric motor proteins Ot-KIF3A/B may be involved in intraspermatic transport and might contribute to structural changes during spermiogenesis.

  12. The octopus genome and the evolution of cephalopod neural and morphological novelties.

    PubMed

    Albertin, Caroline B; Simakov, Oleg; Mitros, Therese; Wang, Z Yan; Pungor, Judit R; Edsinger-Gonzales, Eric; Brenner, Sydney; Ragsdale, Clifton W; Rokhsar, Daniel S

    2015-08-13

    Coleoid cephalopods (octopus, squid and cuttlefish) are active, resourceful predators with a rich behavioural repertoire. They have the largest nervous systems among the invertebrates and present other striking morphological innovations including camera-like eyes, prehensile arms, a highly derived early embryogenesis and a remarkably sophisticated adaptive colouration system. To investigate the molecular bases of cephalopod brain and body innovations, we sequenced the genome and multiple transcriptomes of the California two-spot octopus, Octopus bimaculoides. We found no evidence for hypothesized whole-genome duplications in the octopus lineage. The core developmental and neuronal gene repertoire of the octopus is broadly similar to that found across invertebrate bilaterians, except for massive expansions in two gene families previously thought to be uniquely enlarged in vertebrates: the protocadherins, which regulate neuronal development, and the C2H2 superfamily of zinc-finger transcription factors. Extensive messenger RNA editing generates transcript and protein diversity in genes involved in neural excitability, as previously described, as well as in genes participating in a broad range of other cellular functions. We identified hundreds of cephalopod-specific genes, many of which showed elevated expression levels in such specialized structures as the skin, the suckers and the nervous system. Finally, we found evidence for large-scale genomic rearrangements that are closely associated with transposable element expansions. Our analysis suggests that substantial expansion of a handful of gene families, along with extensive remodelling of genome linkage and repetitive content, played a critical role in the evolution of cephalopod morphological innovations, including their large and complex nervous systems.

  13. The octopus genome and the evolution of cephalopod neural and morphological novelties

    PubMed Central

    Albertin, Caroline B.; Simakov, Oleg; Mitros, Therese; Wang, Z. Yan; Pungor, Judit R.; Edsinger-Gonzalez, Eric; Brenner, Sydney; Ragsdale, Clifton W.; Rokhsar, Daniel S.

    2016-01-01

    Coleoid cephalopods (octopus, squid, and cuttlefish) are active, resourceful predators with a rich behavioral repertoire1. They have the largest nervous systems among the invertebrates2 and present other striking morphological innovations including camera-like eyes, prehensile arms, a highly derived early embryogenesis, and the most sophisticated adaptive coloration system among all animals1,3. To investigate the molecular bases of cephalopod brain and body innovations we sequenced the genome and multiple transcriptomes of the California two-spot octopus, Octopus bimaculoides. We found no evidence for hypothesized whole genome duplications in the octopus lineage4–6. The core developmental and neuronal gene repertoire of the octopus is broadly similar to that found across invertebrate bilaterians, except for massive expansions in two gene families formerly thought to be uniquely enlarged in vertebrates: the protocadherins, which regulate neuronal development, and the C2H2 superfamily of zinc finger transcription factors. Extensive mRNA editing generates transcript and protein diversity in genes involved in neural excitability, as previously described7, as well as in genes participating in a broad range of other cellular functions. We identified hundreds of cephalopod-specific genes, many of which showed elevated expression levels in such specialized structures as the skin, the suckers, and the nervous system. Finally, we found evidence for large-scale genomic rearrangements that are closely associated with transposable element expansions. Our analysis suggests that substantial expansion of a handful of gene families, along with extensive remodeling of genome linkage and repetitive content, played a critical role in the evolution of cephalopod morphological innovations, including their large and complex nervous systems. PMID:26268193

  14. The octopus genome and the evolution of cephalopod neural and morphological novelties.

    PubMed

    Albertin, Caroline B; Simakov, Oleg; Mitros, Therese; Wang, Z Yan; Pungor, Judit R; Edsinger-Gonzales, Eric; Brenner, Sydney; Ragsdale, Clifton W; Rokhsar, Daniel S

    2015-08-13

    Coleoid cephalopods (octopus, squid and cuttlefish) are active, resourceful predators with a rich behavioural repertoire. They have the largest nervous systems among the invertebrates and present other striking morphological innovations including camera-like eyes, prehensile arms, a highly derived early embryogenesis and a remarkably sophisticated adaptive colouration system. To investigate the molecular bases of cephalopod brain and body innovations, we sequenced the genome and multiple transcriptomes of the California two-spot octopus, Octopus bimaculoides. We found no evidence for hypothesized whole-genome duplications in the octopus lineage. The core developmental and neuronal gene repertoire of the octopus is broadly similar to that found across invertebrate bilaterians, except for massive expansions in two gene families previously thought to be uniquely enlarged in vertebrates: the protocadherins, which regulate neuronal development, and the C2H2 superfamily of zinc-finger transcription factors. Extensive messenger RNA editing generates transcript and protein diversity in genes involved in neural excitability, as previously described, as well as in genes participating in a broad range of other cellular functions. We identified hundreds of cephalopod-specific genes, many of which showed elevated expression levels in such specialized structures as the skin, the suckers and the nervous system. Finally, we found evidence for large-scale genomic rearrangements that are closely associated with transposable element expansions. Our analysis suggests that substantial expansion of a handful of gene families, along with extensive remodelling of genome linkage and repetitive content, played a critical role in the evolution of cephalopod morphological innovations, including their large and complex nervous systems. PMID:26268193

  15. The role of DNA methylation on Octopus vulgaris development and their perspectives

    PubMed Central

    Díaz-Freije, Eva; Gestal, Camino; Castellanos-Martínez, Sheila; Morán, Paloma

    2014-01-01

    DNA methylation is a common regulator of gene expression and development in mammalian and other vertebrate genomes. DNA methylation has been studied so far in a few bivalve mollusk species, finding a wide spectrum of levels. We focused our study in the common octopus, Octopus vulgaris, an important organism for neuroscience, physiology and ethology research as well as for human consumption. We aim to confirm the existence of DNA methylation in O. vulgaris and ultimately, if methylation plays a role in gene regulation during octopus development. We used a genome-wide approach, methylation-sensitive amplified polymorphism (MSAP), firstly in four different tissues from the same specimens from adult benthonic individuals to test whether gene expression is regulated by methylation. Secondly, we tested the hypothesis that methylation underlies development by assessing MSAP patters from paralarvae to adult developmental stages. Our data indicate that octopus genome is widely methylated since clear differences can be observed, and the methylation pattern changes with the development. The statistical analyses showed significant differences in methylation pattern between paralarvae, where higher internal cytosine methylation is observed, and the three other post-hatching stages. This suggests an important role of cytosine methylation during the first step of development, when major morphological changes take place. However, methylation seems to have little effect on gene expression during the benthonic phase, since no significant effect was revealed in the analyses of molecular variance (AMOVA) performed. Our observations highlight the importance of epigenetic mechanisms in the first developmental steps of the common octopus and opens new perspectives to overcome high mortality rate during paralarvae growth. Thus, better understanding the molecular regulation patterns could lead to new approaches that increase the efficiency of husbandry of this emergent species for

  16. Nuclear and mitochondrial markers reveal evidence for genetically segregated cryptic speciation in giant Pacific octopuses from Prince William Sound, Alaska

    USGS Publications Warehouse

    Toussaint, Rebecca K.; Scheel, David; Sage, G.K.; Talbot, S.L.

    2012-01-01

    Multiple species of large octopus are known from the north Pacific waters around Japan, however only one large species is known in the Gulf of Alaska (the giant Pacific octopus, Enteroctopus dofleini). Current taxonomy of E. dofleini is based on geographic and morphological characteristics, although with advances in genetic technology that is changing. Here, we used two mitochondrial genes (cytochrome b and cytochrome oxidase I), three nuclear genes (rhodopsin, octopine dehydrogenase, and paired-box 6), and 18 microsatellite loci for phylogeographic and phylogenetic analyses of octopuses collected from across southcentral and the eastern Aleutian Islands (Dutch Harbor), Alaska. Our results suggest the presence of a cryptic Enteroctopus species that is allied to, but distinguished from E. dofleini in Prince William Sound, Alaska. Existence of an undescribed and previously unrecognized taxon raises important questions about the taxonomy of octopus in southcentral Alaska waters.

  17. Occurrence of a tetrodotoxin-like compound in the eggs of the venomous blue-ringed octopus (Hapalochlaena maculosa).

    PubMed

    Sheumack, D D; Howden, M E; Spence, I

    1984-01-01

    A lethal toxin was isolated and partly purified from the eggs of the blue-ringed octopus, Hapalochlaena maculosa. Examination of the toxin by thin layer chromatography, isoelectric focusing and its effects upon the compound nerve action potentials of the toad sciatic nerve gave results that were indistinguishable from those displayed by authentic tetrodotoxin, the toxin present in the venom glands of the octopus. PMID:6441311

  18. Skin lesion-associated pathogens from Octopus vulgaris: first detection of Photobacterium swingsii, Lactococcus garvieae and betanodavirus.

    PubMed

    Fichi, G; Cardeti, G; Perrucci, S; Vanni, A; Cersini, A; Lenzi, C; De Wolf, T; Fronte, B; Guarducci, M; Susini, F

    2015-07-23

    The common octopus Octopus vulgaris Cuvier, 1798 is extremely important in fisheries and is a useful protein source in most Mediterranean countries. Here we investigated pathogens associated with skin lesions in 9 naturally deceased specimens that included both cultured and wild common octopus. Within 30 min after death, each octopus was stored at 4°C and microbiologically examined within 24 h. Bacterial colonies, cultured from swabs taken from the lesions, were examined using taxonomical and biochemical analyses. Vibrio alginolyticus and V. parahaemolyticus were only isolated from cultured animals. A conventional PCR targeting the 16S ribosomal RNA (rRNA) gene and sequencing were performed on 2 bacterial isolates that remained unidentified after taxonomical and biochemical analysis. The sequence results indicated that the bacteria had a 99% identity with Lactococcus garvieae and Photobacterium swingsii. L. garvieae was confirmed using a specific PCR based on the 16S-23S rRNA internal transcribed spacer region, while P. swingsii was confirmed by phylogenetic analyses. Although all animals examined were found to be infected by the protozoan species Aggregata octopiana localised in the intestines, it was also present in skin lesions of 2 of the animals. Betanodavirus was detected in both cultured and wild individuals by cell culture, PCR and electron microscopy. These findings are the first report of L. garvieae and betanodavirus from skin lesions of common octopus and the first identification of P. swingsii both in octopus skin lesions and in marine invertebrates in Italy. PMID:26203886

  19. Skin lesion-associated pathogens from Octopus vulgaris: first detection of Photobacterium swingsii, Lactococcus garvieae and betanodavirus.

    PubMed

    Fichi, G; Cardeti, G; Perrucci, S; Vanni, A; Cersini, A; Lenzi, C; De Wolf, T; Fronte, B; Guarducci, M; Susini, F

    2015-07-23

    The common octopus Octopus vulgaris Cuvier, 1798 is extremely important in fisheries and is a useful protein source in most Mediterranean countries. Here we investigated pathogens associated with skin lesions in 9 naturally deceased specimens that included both cultured and wild common octopus. Within 30 min after death, each octopus was stored at 4°C and microbiologically examined within 24 h. Bacterial colonies, cultured from swabs taken from the lesions, were examined using taxonomical and biochemical analyses. Vibrio alginolyticus and V. parahaemolyticus were only isolated from cultured animals. A conventional PCR targeting the 16S ribosomal RNA (rRNA) gene and sequencing were performed on 2 bacterial isolates that remained unidentified after taxonomical and biochemical analysis. The sequence results indicated that the bacteria had a 99% identity with Lactococcus garvieae and Photobacterium swingsii. L. garvieae was confirmed using a specific PCR based on the 16S-23S rRNA internal transcribed spacer region, while P. swingsii was confirmed by phylogenetic analyses. Although all animals examined were found to be infected by the protozoan species Aggregata octopiana localised in the intestines, it was also present in skin lesions of 2 of the animals. Betanodavirus was detected in both cultured and wild individuals by cell culture, PCR and electron microscopy. These findings are the first report of L. garvieae and betanodavirus from skin lesions of common octopus and the first identification of P. swingsii both in octopus skin lesions and in marine invertebrates in Italy.

  20. Life history of the bathyal octopus Pteroctopus tetracirrhus (Mollusca, Cephalopoda) in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Quetglas, Antoni; Ordines, Francesc; González, María; Franco, Ignacio

    2009-08-01

    The life cycle of the deep-sea octopus Pteroctopus tetracirrhus was studied from monthly samples obtained throughout the year in different areas of the western Mediterranean (mainly around the Balearic Islands and along the coast of the Iberian Peninsula). A total of 373 individuals (205 females, 168 males) were analyzed; females ranged from 4.5 to 14.0 cm mantle length (ML) and males from 4.5 to 11.5 cm ML. There were few small-sized octopuses (<7 cm ML) in the samples, which might indicate that these individuals inhabit rocky grounds that are not accessible to trawlers or waters deeper than the maximum depth sampled (800 m). The species occurred more frequently around the Balearic Islands than along the Iberian Peninsula as they appeared in 20% and 7%, respectively, of the hauls in these areas. The octopus inhabits the lower continental shelf and upper slope in both areas, primarily between 200 and 500 m depth. Modal lengths were followed from autumn, when recruits were caught by trawlers, to summer, when reproduction took place. Females grew from 8 to 10 cm ML from winter to spring, but this modal size did not increase further in summer; males grew from 7 to 9 cm ML from winter to spring. The total disappearance of large individuals after summer suggests a life cycle lasting a single year. The evolution of the monthly mean sizes showed that the growth was best described by log-linear functions in both sexes. The length at first maturity was clearly higher in females (12 cm ML) than in males (8 cm ML). A total of 30 different prey items, belonging to four major taxonomic groups (crustaceans, osteichthyes, cephalopods and gastropods), were identified in the stomach contents. The diet of the octopus was based on crustaceans and teleosts, which accounted for 75% and 23% of the prey items, respectively. Cephalopods and gastropods were accessory prey as they only represented 1.6% and 0.7%, respectively, of the total. The octopus showed a marked preference for the

  1. Combined Transcriptomic and Proteomic Analysis of the Posterior Salivary Gland from the Southern Blue-Ringed Octopus and the Southern Sand Octopus.

    PubMed

    Whitelaw, Brooke L; Strugnell, Jan M; Faou, Pierre; da Fonseca, Rute R; Hall, Nathan E; Norman, Mark; Finn, Julian; Cooke, Ira R

    2016-09-01

    This study provides comprehensive proteomic profiles from the venom producing posterior salivary glands of octopus (superorder Octopodiformes) species. A combined transcriptomic and proteomic approach was used to identify 1703 proteins from the posterior salivary gland of the southern blue-ringed octopus, Hapalochlaena maculosa and 1300 proteins from the posterior salivary gland of the southern sand octopus, Octopus kaurna. The two proteomes were broadly similar; clustering of proteins into orthogroups revealed 937 that were shared between species. Serine proteases were particularly diverse and abundant in both species. Other abundant proteins included a large number of secreted proteins, many of which had no known conserved domains, or homology to proteins with known function. On the basis of homology to known venom proteins, 23 putative toxins were identified in H. maculosa and 24 in O. kaurna. These toxins span nine protein families: CAP (cysteine rich secretory proteins, antigen 5, parthenogenesis related), chitinase, carboxylesterase, DNase, hyaluronidase, metalloprotease, phospholipase, serine protease and tachykinin. Serine proteases were responsible for 70.9% and 86.3% of putative toxin expression in H. maculosa and O. kaurna, respectively, as determined using intensity based absolute quantification (iBAQ) measurements. Phylogenetic analysis of the putative toxin serine proteases revealed a similar suite of diverse proteins present in both species. Posterior salivary gland composition of H. maculosa and O. kaurna differ in several key aspects. While O. kaurna expressed the proteinaceous neurotoxin, tachykinin, this was absent from H. maculosa, perhaps reflecting the acquisition of a potent nonproteinaceous neurotoxin, tetrodotoxin (TTX) produced by bacteria in the salivary glands of that species. The dispersal factor, hyaluronidase was particularly abundant in H. maculosa. Chitinase was abundant in both species and is believed to facilitate

  2. Combined Transcriptomic and Proteomic Analysis of the Posterior Salivary Gland from the Southern Blue-Ringed Octopus and the Southern Sand Octopus.

    PubMed

    Whitelaw, Brooke L; Strugnell, Jan M; Faou, Pierre; da Fonseca, Rute R; Hall, Nathan E; Norman, Mark; Finn, Julian; Cooke, Ira R

    2016-09-01

    This study provides comprehensive proteomic profiles from the venom producing posterior salivary glands of octopus (superorder Octopodiformes) species. A combined transcriptomic and proteomic approach was used to identify 1703 proteins from the posterior salivary gland of the southern blue-ringed octopus, Hapalochlaena maculosa and 1300 proteins from the posterior salivary gland of the southern sand octopus, Octopus kaurna. The two proteomes were broadly similar; clustering of proteins into orthogroups revealed 937 that were shared between species. Serine proteases were particularly diverse and abundant in both species. Other abundant proteins included a large number of secreted proteins, many of which had no known conserved domains, or homology to proteins with known function. On the basis of homology to known venom proteins, 23 putative toxins were identified in H. maculosa and 24 in O. kaurna. These toxins span nine protein families: CAP (cysteine rich secretory proteins, antigen 5, parthenogenesis related), chitinase, carboxylesterase, DNase, hyaluronidase, metalloprotease, phospholipase, serine protease and tachykinin. Serine proteases were responsible for 70.9% and 86.3% of putative toxin expression in H. maculosa and O. kaurna, respectively, as determined using intensity based absolute quantification (iBAQ) measurements. Phylogenetic analysis of the putative toxin serine proteases revealed a similar suite of diverse proteins present in both species. Posterior salivary gland composition of H. maculosa and O. kaurna differ in several key aspects. While O. kaurna expressed the proteinaceous neurotoxin, tachykinin, this was absent from H. maculosa, perhaps reflecting the acquisition of a potent nonproteinaceous neurotoxin, tetrodotoxin (TTX) produced by bacteria in the salivary glands of that species. The dispersal factor, hyaluronidase was particularly abundant in H. maculosa. Chitinase was abundant in both species and is believed to facilitate

  3. Coccidian infection may explain the differences in the life history of octopus host populations.

    PubMed

    Storero, Lorena P; Narvarte, Maite A

    2013-11-01

    The prevalence of coccidian parasites in three Octopus tehuelchus populations from San Matías Gulf (Patagonia, Argentina) is compared. The prevalence was similar between sexes, but varied between seasons (being highest during cold months) and sites. Islote Lobos had the highest prevalence (42.7-100%) followed by San Antonio Bay (0-66%) and El Fuerte (0-24.5%). Octopuses under 27 mm of dorsal mantle length showed a low prevalence (less than 50%), which increased with size. We hypothesize that the high prevalence of parasites, which affect the three populations differentially, could account for the observed variability in life-span and growth, size-frequency distributions, reproduction and densities of O. tehuelchus populations.

  4. Functional characterization on invertebrate and vertebrate tissues of tachykinin peptides from octopus venoms.

    PubMed

    Ruder, Tim; Ali, Syed Abid; Ormerod, Kiel; Brust, Andreas; Roymanchadi, Mary-Louise; Ventura, Sabatino; Undheim, Eivind A B; Jackson, Timothy N W; Mercier, A Joffre; King, Glenn F; Alewood, Paul F; Fry, Bryan G

    2013-09-01

    It has been previously shown that octopus venoms contain novel tachykinin peptides that despite being isolated from an invertebrate, contain the motifs characteristic of vertebrate tachykinin peptides rather than being more like conventional invertebrate tachykinin peptides. Therefore, in this study we examined the effect of three variants of octopus venom tachykinin peptides on invertebrate and vertebrate tissues. While there were differential potencies between the three peptides, their relative effects were uniquely consistent between invertebrate and vertebrae tissue assays. The most potent form (OCT-TK-III) was not only the most anionically charged but also was the most structurally stable. These results not only reveal that the interaction of tachykinin peptides is more complex than previous structure-function theories envisioned, but also reinforce the fundamental premise that animal venoms are rich resources of novel bioactive molecules, which are useful investigational ligands and some of which may be useful as lead compounds for drug design and development.

  5. The gyri of the octopus vertical lobe have distinct neurochemical identities.

    PubMed

    Shigeno, Shuichi; Ragsdale, Clifton W

    2015-06-15

    The cephalopod vertical lobe is the largest learning and memory structure known in invertebrate nervous systems. It is part of the visual learning circuit of the central brain, which also includes the superior frontal and subvertical lobes. Despite the well-established functional importance of this system, little is known about neuropil organization of these structures and there is to date no evidence that the five longitudinal gyri of the vertical lobe, perhaps the most distinctive morphological feature of the octopus brain, differ in their connections or molecular identities. We studied the histochemical organization of these structures in hatchling and adult Octopus bimaculoides brains with immunostaining for serotonin, octopus gonadotropin-releasing hormone (oGNRH), and octopressin-neurophysin (OP-NP). Our major finding is that the five lobules forming the vertical lobe gyri have distinct neurochemical signatures. This is most prominent in the hatchling brain, where the median and mediolateral lobules are enriched in OP-NP fibers, the lateral lobule is marked by oGNRH innervation, and serotonin immunostaining heavily labels the median and lateral lobules. A major source of input to the vertical lobe is the superior frontal lobe, which is dominated by a neuropil of interweaving fiber bundles. We have found that this neuropil also has an intrinsic neurochemical organization: it is partitioned into territories alternately enriched or impoverished in oGNRH-containing fascicles. Our findings establish that the constituent lobes of the octopus superior frontal-vertical system have an intricate internal anatomy, one likely to reflect the presence of functional subsystems within cephalopod learning circuitry.

  6. Octopus arm movements under constrained conditions: adaptation, modification and plasticity of motor primitives.

    PubMed

    Richter, Jonas N; Hochner, Binyamin; Kuba, Michael J

    2015-04-01

    The motor control of the eight highly flexible arms of the common octopus (Octopus vulgaris) has been the focus of several recent studies. Our study is the first to manage to introduce a physical constraint to an octopus arm and investigate the adaptability of stereotypical bend propagation in reaching movements and the pseudo-limb articulation during fetching. Subjects (N=6) were placed inside a transparent Perspex box with a hole at the center that allowed the insertion of a single arm. Animals had to reach out through the hole toward a target, to retrieve a food reward and fetch it. All subjects successfully adjusted their movements to the constraint without an adaptation phase. During reaching tasks, the animals showed two movement strategies: stereotypical bend propagation reachings, which were established at the hole of the Perspex box and variant waving-like movements that showed no bend propagations. During fetching movements, no complete pseudo-joint fetching was observed outside the box and subjects pulled their arms through the hole in a pull-in like movement. Our findings show that there is some flexibility in the octopus motor system to adapt to a novel situation. However, at present, it seems that these changes are more an effect of random choices between different alternative motor programs, without showing clear learning effects in the choice between the alternatives. Interestingly, animals were able to adapt the fetching movements to the physical constraint, or as an alternative explanation, they could switch the motor primitive fetching to a different motor primitive 'arm pulling'. PMID:25687436

  7. The gyri of the octopus vertical lobe have distinct neurochemical identities.

    PubMed

    Shigeno, Shuichi; Ragsdale, Clifton W

    2015-06-15

    The cephalopod vertical lobe is the largest learning and memory structure known in invertebrate nervous systems. It is part of the visual learning circuit of the central brain, which also includes the superior frontal and subvertical lobes. Despite the well-established functional importance of this system, little is known about neuropil organization of these structures and there is to date no evidence that the five longitudinal gyri of the vertical lobe, perhaps the most distinctive morphological feature of the octopus brain, differ in their connections or molecular identities. We studied the histochemical organization of these structures in hatchling and adult Octopus bimaculoides brains with immunostaining for serotonin, octopus gonadotropin-releasing hormone (oGNRH), and octopressin-neurophysin (OP-NP). Our major finding is that the five lobules forming the vertical lobe gyri have distinct neurochemical signatures. This is most prominent in the hatchling brain, where the median and mediolateral lobules are enriched in OP-NP fibers, the lateral lobule is marked by oGNRH innervation, and serotonin immunostaining heavily labels the median and lateral lobules. A major source of input to the vertical lobe is the superior frontal lobe, which is dominated by a neuropil of interweaving fiber bundles. We have found that this neuropil also has an intrinsic neurochemical organization: it is partitioned into territories alternately enriched or impoverished in oGNRH-containing fascicles. Our findings establish that the constituent lobes of the octopus superior frontal-vertical system have an intricate internal anatomy, one likely to reflect the presence of functional subsystems within cephalopod learning circuitry. PMID:25644267

  8. Octopus-Inspired Smart Adhesive Pads for Transfer Printing of Semiconducting Nanomembranes.

    PubMed

    Lee, Hochan; Um, Doo-Seung; Lee, Youngsu; Lim, Seongdong; Kim, Hyung-Jun; Ko, Hyunhyub

    2016-09-01

    By mimicking muscle actuation to control cavity-pressure-induced adhesion of octopus suckers, smart adhesive pads are developed in which the thermoresponsive actuation of a hydrogel layer on elastomeric microcavity pads enables excellent switchable adhesion in response to a thermal stimulus (maximum adhesive strength: 94 kPa, adhesion switching ratio: ≈293 for temperature change between 22 and 61 °C). PMID:27322886

  9. Octopus arm movements under constrained conditions: adaptation, modification and plasticity of motor primitives.

    PubMed

    Richter, Jonas N; Hochner, Binyamin; Kuba, Michael J

    2015-04-01

    The motor control of the eight highly flexible arms of the common octopus (Octopus vulgaris) has been the focus of several recent studies. Our study is the first to manage to introduce a physical constraint to an octopus arm and investigate the adaptability of stereotypical bend propagation in reaching movements and the pseudo-limb articulation during fetching. Subjects (N=6) were placed inside a transparent Perspex box with a hole at the center that allowed the insertion of a single arm. Animals had to reach out through the hole toward a target, to retrieve a food reward and fetch it. All subjects successfully adjusted their movements to the constraint without an adaptation phase. During reaching tasks, the animals showed two movement strategies: stereotypical bend propagation reachings, which were established at the hole of the Perspex box and variant waving-like movements that showed no bend propagations. During fetching movements, no complete pseudo-joint fetching was observed outside the box and subjects pulled their arms through the hole in a pull-in like movement. Our findings show that there is some flexibility in the octopus motor system to adapt to a novel situation. However, at present, it seems that these changes are more an effect of random choices between different alternative motor programs, without showing clear learning effects in the choice between the alternatives. Interestingly, animals were able to adapt the fetching movements to the physical constraint, or as an alternative explanation, they could switch the motor primitive fetching to a different motor primitive 'arm pulling'.

  10. Development of microsatellite markers to genetically differentiate populations of Octopus minor from Korea and China.

    PubMed

    Kang, Jung-Ha; Kim, Yi-Kyung; Park, Jung-Youn; An, Chel-Min; Jun, Je-Chun

    2012-08-01

    Of the more than 300 octopus species, Octopus minor is one of the most popular and economically important species in Eastern Asia, including Korea, along with O. vulgaris, O. ocellatus, and O. aegina. We developed 19 microsatellite markers from Octopus minor and eight polymorphic markers were developed to analyze the genetic diversity and relationships among four octopus populations from Korea and three from China. The number of alleles per locus varied from 10 to 49, and allelic richness per locus ranged from 2 to 16.4 across all populations. The average allele number among the populations was 11.1, with a minimum of 8.3 and a maximum of 13.6. The mean allelic richness was 8.7 in all populations. The Hardy-Weinberg equilibrium (HWE) test revealed significant deviation in 19 of the 56 single-locus sites, and null alleles were presumed in five of eight loci. The pairwise F ( ST ) values between populations from Korea and China differed significantly in all pairwise comparisons. The genetic distances between the China and Korea samples ranged from 0.161 to 0.454. The genetic distances among the populations from Korea ranged from 0.033 to 0.090, with an average of 0.062; those among populations from China ranged from 0.191 to 0.316, with an average of 0.254. The populations from Korea and China formed clearly separated into clusters via an unweighted pair group method with arithmetic mean dendrogram. Furthermore, a population from muddy flats on the western coast of the Korean Peninsula and one from a rocky area on Jeju Island formed clearly separated subclusters. An assignment test based on the allele distribution discriminated between the Korean and Chinese origins with 96.9 % accuracy.

  11. Development of microsatellite markers to genetically differentiate populations of Octopus minor from Korea and China.

    PubMed

    Kang, Jung-Ha; Kim, Yi-Kyung; Park, Jung-Youn; An, Chel-Min; Jun, Je-Chun

    2012-08-01

    Of the more than 300 octopus species, Octopus minor is one of the most popular and economically important species in Eastern Asia, including Korea, along with O. vulgaris, O. ocellatus, and O. aegina. We developed 19 microsatellite markers from Octopus minor and eight polymorphic markers were developed to analyze the genetic diversity and relationships among four octopus populations from Korea and three from China. The number of alleles per locus varied from 10 to 49, and allelic richness per locus ranged from 2 to 16.4 across all populations. The average allele number among the populations was 11.1, with a minimum of 8.3 and a maximum of 13.6. The mean allelic richness was 8.7 in all populations. The Hardy-Weinberg equilibrium (HWE) test revealed significant deviation in 19 of the 56 single-locus sites, and null alleles were presumed in five of eight loci. The pairwise F ( ST ) values between populations from Korea and China differed significantly in all pairwise comparisons. The genetic distances between the China and Korea samples ranged from 0.161 to 0.454. The genetic distances among the populations from Korea ranged from 0.033 to 0.090, with an average of 0.062; those among populations from China ranged from 0.191 to 0.316, with an average of 0.254. The populations from Korea and China formed clearly separated into clusters via an unweighted pair group method with arithmetic mean dendrogram. Furthermore, a population from muddy flats on the western coast of the Korean Peninsula and one from a rocky area on Jeju Island formed clearly separated subclusters. An assignment test based on the allele distribution discriminated between the Korean and Chinese origins with 96.9 % accuracy. PMID:22707143

  12. Phylogenetic analysis of the hyperthermophilic pink filament community in Octopus Spring, Yellowstone National Park

    SciTech Connect

    Reysenbach, A.L.; Wickham, G.S.; Pace, N.R.

    1994-06-01

    This study uses a molecular phylogenetic approach to characterize the pink filament community at the outflow of Octopus Spring in Yellowstone National Park. The temperature range of the spring is from 84 to 88 C. The authors show that the pink filaments are most closely related to the hydrogen-oxidizing bacterium Aquifex pyrophilus and a close relative Hydrogenobacter thermophilus. 38 refs., 4 figs., 1 tab.

  13. Distribution of tetrodotoxin in the body of the blue-ringed octopus (Hapalochlaena maculosa).

    PubMed

    Yotsu-Yamashita, Mari; Mebs, Dietrich; Flachsenberger, Wolfgang

    2007-03-01

    Tetrodotoxin (TTX) was quantitatively assayed in six specimens of semi-adult blue-ringed octopus, Hapalochlaena maculosa, by a post-column fluorescent-HPLC system. TTX was found to be present in all body parts, e.g. in high concentrations in the arms followed by the abdomen and cephalothorax. The toxin is not associated exclusively with the posterior salivary gland. PMID:17188731

  14. Soft-robotic arm inspired by the octopus: II. From artificial requirements to innovative technological solutions.

    PubMed

    Mazzolai, B; Margheri, L; Cianchetti, M; Dario, P; Laschi, C

    2012-06-01

    Soft robotics is a current focus in robotics research because of the expected capability of soft robots to better interact with real-world environments. As a point of inspiration in the development of innovative technologies in soft robotics, octopuses are particularly interesting 'animal models'. Octopus arms have unique biomechanical capabilities that combine significant pliability with the ability to exert a great deal of force, because they lack rigid structures but can change and control their degree of stiffness. The octopus arm motor capability is a result of the peculiar arrangement of its muscles and the properties of its tissues. These special abilities have been investigated by the authors in a specific study dedicated to identifying the key principles underlying these biological functions and deriving engineering requirements for robotics solutions. This paper, which is the second in a two-part series, presents how the identified requirements can be used to create innovative technological solutions, such as soft materials, mechanisms and actuators. Experiments indicate the ability of these proposed solutions to ensure the same performance as in the biological model in terms of compliance, elongation and force. These results represent useful and relevant components of innovative soft-robotic systems and suggest their potential use to create a new generation of highly dexterous, soft-bodied robots.

  15. Octopuses use a human-like strategy to control precise point-to-point arm movements.

    PubMed

    Sumbre, Germán; Fiorito, Graziano; Flash, Tamar; Hochner, Binyamin

    2006-04-18

    One of the key problems in motor control is mastering or reducing the number of degrees of freedom (DOFs) through coordination. This problem is especially prominent with hyper-redundant limbs such as the extremely flexible arm of the octopus. Several strategies for simplifying these control problems have been suggested for human point-to-point arm movements. Despite the evolutionary gap and morphological differences, humans and octopuses evolved similar strategies when fetching food to the mouth. To achieve this precise point-to-point-task, octopus arms generate a quasi-articulated structure based on three dynamic joints. A rotational movement around these joints brings the object to the mouth . Here, we describe a peripheral neural mechanism-two waves of muscle activation propagate toward each other, and their collision point sets the medial-joint location. This is a remarkably simple mechanism for adjusting the length of the segments according to where the object is grasped. Furthermore, similar to certain human arm movements, kinematic invariants were observed at the joint level rather than at the end-effector level, suggesting intrinsic control coordination. The evolutionary convergence to similar geometrical and kinematic features suggests that a kinematically constrained articulated limb controlled at the level of joint space is the optimal solution for precise point-to-point movements.

  16. An octopus-bioinspired solution to movement and manipulation for soft robots.

    PubMed

    Calisti, M; Giorelli, M; Levy, G; Mazzolai, B; Hochner, B; Laschi, C; Dario, P

    2011-09-01

    Soft robotics is a challenging and promising branch of robotics. It can drive significant improvements across various fields of traditional robotics, and contribute solutions to basic problems such as locomotion and manipulation in unstructured environments. A challenging task for soft robotics is to build and control soft robots able to exert effective forces. In recent years, biology has inspired several solutions to such complex problems. This study aims at investigating the smart solution that the Octopus vulgaris adopts to perform a crawling movement, with the same limbs used for grasping and manipulation. An ad hoc robot was designed and built taking as a reference a biological hypothesis on crawling. A silicone arm with cables embedded to replicate the functionality of the arm muscles of the octopus was built. This novel arm is capable of pushing-based locomotion and object grasping, mimicking the movements that octopuses adopt when crawling. The results support the biological observations and clearly show a suitable way to build a more complex soft robot that, with minimum control, can perform diverse tasks.

  17. Immunolocalization of choline acetyltransferase of common type in the central brain mass of Octopus vulgaris

    PubMed Central

    Casini, A.; Vaccaro, R.; D'Este, L.; Sakaue, Y.; Bellier, J.P.; Kimura, H.; Renda, T.G.

    2012-01-01

    Acetylcholine, the first neurotransmitter to be identified in the vertebrate frog, is widely distributed among the animal kingdom. The presence of a large amount of acetylcholine in the nervous system of cephalopods is well known from several biochemical and physiological studies. However, little is known about the precise distribution of cholinergic structures due to a lack of a suitable histochemical technique for detecting acetylcholine. The most reliable method to visualize the cholinergic neurons is the immunohistochemical localization of the enzyme choline acetyltransferase, the synthetic enzyme of acetylcholine. Following our previous study on the distribution patterns of cholinergic neurons in the Octopus vulgaris visual system, using a novel antibody that recognizes choline acetyltransferase of the common type (cChAT), now we extend our investigation on the octopus central brain mass. When applied on sections of octopus central ganglia, immunoreactivity for cChAT was detected in cell bodies of all central brain mass lobes with the notable exception of the subfrontal and subvertical lobes. Positive varicosed nerves fibers where observed in the neuropil of all central brain mass lobes. PMID:23027350

  18. Learning the inverse kinetics of an octopus-like manipulator in three-dimensional space.

    PubMed

    Giorelli, M; Renda, F; Calisti, M; Arienti, A; Ferri, G; Laschi, C

    2015-06-01

    This work addresses the inverse kinematics problem of a bioinspired octopus-like manipulator moving in three-dimensional space. The bioinspired manipulator has a conical soft structure that confers the ability of twirling around objects as a real octopus arm does. Despite the simple design, the soft conical shape manipulator driven by cables is described by nonlinear differential equations, which are difficult to solve analytically. Since exact solutions of the equations are not available, the Jacobian matrix cannot be calculated analytically and the classical iterative methods cannot be used. To overcome the intrinsic problems of methods based on the Jacobian matrix, this paper proposes a neural network learning the inverse kinematics of a soft octopus-like manipulator driven by cables. After the learning phase, a feed-forward neural network is able to represent the relation between manipulator tip positions and forces applied to the cables. Experimental results show that a desired tip position can be achieved in a short time, since heavy computations are avoided, with a degree of accuracy of 8% relative average error with respect to the total arm length. PMID:25970238

  19. Time-dependent density-functional theory in massively parallel computer architectures: the OCTOPUS project.

    PubMed

    Andrade, Xavier; Alberdi-Rodriguez, Joseba; Strubbe, David A; Oliveira, Micael J T; Nogueira, Fernando; Castro, Alberto; Muguerza, Javier; Arruabarrena, Agustin; Louie, Steven G; Aspuru-Guzik, Alán; Rubio, Angel; Marques, Miguel A L

    2012-06-13

    Octopus is a general-purpose density-functional theory (DFT) code, with a particular emphasis on the time-dependent version of DFT (TDDFT). In this paper we present the ongoing efforts to achieve the parallelization of octopus. We focus on the real-time variant of TDDFT, where the time-dependent Kohn-Sham equations are directly propagated in time. This approach has great potential for execution in massively parallel systems such as modern supercomputers with thousands of processors and graphics processing units (GPUs). For harvesting the potential of conventional supercomputers, the main strategy is a multi-level parallelization scheme that combines the inherent scalability of real-time TDDFT with a real-space grid domain-partitioning approach. A scalable Poisson solver is critical for the efficiency of this scheme. For GPUs, we show how using blocks of Kohn-Sham states provides the required level of data parallelism and that this strategy is also applicable for code optimization on standard processors. Our results show that real-time TDDFT, as implemented in octopus, can be the method of choice for studying the excited states of large molecular systems in modern parallel architectures. PMID:22562950

  20. Learning the inverse kinetics of an octopus-like manipulator in three-dimensional space.

    PubMed

    Giorelli, M; Renda, F; Calisti, M; Arienti, A; Ferri, G; Laschi, C

    2015-05-13

    This work addresses the inverse kinematics problem of a bioinspired octopus-like manipulator moving in three-dimensional space. The bioinspired manipulator has a conical soft structure that confers the ability of twirling around objects as a real octopus arm does. Despite the simple design, the soft conical shape manipulator driven by cables is described by nonlinear differential equations, which are difficult to solve analytically. Since exact solutions of the equations are not available, the Jacobian matrix cannot be calculated analytically and the classical iterative methods cannot be used. To overcome the intrinsic problems of methods based on the Jacobian matrix, this paper proposes a neural network learning the inverse kinematics of a soft octopus-like manipulator driven by cables. After the learning phase, a feed-forward neural network is able to represent the relation between manipulator tip positions and forces applied to the cables. Experimental results show that a desired tip position can be achieved in a short time, since heavy computations are avoided, with a degree of accuracy of 8% relative average error with respect to the total arm length.

  1. Immunolocalization of choline acetyltransferase of common type in the central brain mass of Octopus vulgaris.

    PubMed

    Casini, A; Vaccaro, R; D'Este, L; Sakaue, Y; Bellier, J P; Kimura, H; Renda, T G

    2012-07-19

    Acetylcholine, the first neurotransmitter to be identified in the vertebrate frog, is widely distributed among the animal kingdom. The presence of a large amount of acetylcholine in the nervous system of cephalopods is well known from several biochemical and physiological studies. However, little is known about the precise distribution of cholinergic structures due to a lack of a suitable histochemical technique for detecting acetylcholine. The most reliable method to visualize the cholinergic neurons is the immunohistochemical localization of the enzyme choline acetyltransferase, the synthetic enzyme of acetylcholine. Following our previous study on the distribution patterns of cholinergic neurons in the Octopus vulgaris visual system, using a novel antibody that recognizes choline acetyltransferase of the common type (cChAT), now we extend our investigation on the octopus central brain mass. When applied on sections of octopus central ganglia, immunoreactivity for cChAT was detected in cell bodies of all central brain mass lobes with the notable exception of the subfrontal and subvertical lobes. Positive varicosed nerves fibers where observed in the neuropil of all central brain mass lobes.

  2. Time-dependent density-functional theory in massively parallel computer architectures: the octopus project

    NASA Astrophysics Data System (ADS)

    Andrade, Xavier; Alberdi-Rodriguez, Joseba; Strubbe, David A.; Oliveira, Micael J. T.; Nogueira, Fernando; Castro, Alberto; Muguerza, Javier; Arruabarrena, Agustin; Louie, Steven G.; Aspuru-Guzik, Alán; Rubio, Angel; Marques, Miguel A. L.

    2012-06-01

    Octopus is a general-purpose density-functional theory (DFT) code, with a particular emphasis on the time-dependent version of DFT (TDDFT). In this paper we present the ongoing efforts to achieve the parallelization of octopus. We focus on the real-time variant of TDDFT, where the time-dependent Kohn-Sham equations are directly propagated in time. This approach has great potential for execution in massively parallel systems such as modern supercomputers with thousands of processors and graphics processing units (GPUs). For harvesting the potential of conventional supercomputers, the main strategy is a multi-level parallelization scheme that combines the inherent scalability of real-time TDDFT with a real-space grid domain-partitioning approach. A scalable Poisson solver is critical for the efficiency of this scheme. For GPUs, we show how using blocks of Kohn-Sham states provides the required level of data parallelism and that this strategy is also applicable for code optimization on standard processors. Our results show that real-time TDDFT, as implemented in octopus, can be the method of choice for studying the excited states of large molecular systems in modern parallel architectures.

  3. Purification and partial characterization of an agglutinin from Octopus maya serum.

    PubMed

    Alpuche, Juan; Pereyra, Ali; Mendoza-Hernández, Guillermo; Agundis, Concepción; Rosas, Carlos; Zenteno, Edgar

    2010-05-01

    A 66-kDa lectin (OmA) was purified from the serum of the Yucatan peninsula endemic octopus (Octopus maya) by a single step affinity chromatography on glutaraldehyde-fixed stroma from rat erythrocytes. OmA corresponds to 0.8% of the total circulating protein in the hemolymph; it is composed of three equal subunits of 22kDa each, and 7.4% of linked carbohydrates. The amino acids' composition indicated that agglutinin contained mainly aspartic and glutamic acids, and cysteine and methionine were identified in minor proportion. OmA agglutinates mainly rat, guinea pig, and rabbit erythrocytes, and this activity is partially inhibited by galactosamine, melobiose, galacturonic acid, mannose, and methyl alpha and beta galactosides. Hemagglutinating activity is not dependent on divalent cations, such as Ca(2+), Mg(2+), or Mn(2+). The OmA subunits showed no identity for any lectin in databases but partial identity with the type A hemocyanin from Octopus dolfleini hemolymph; the main similarities are related to tyrosinase domains and copper A and B sites that conform to the oxygen-binding site of hemocyanin. PMID:20105460

  4. Time-dependent density-functional theory in massively parallel computer architectures: the OCTOPUS project.

    PubMed

    Andrade, Xavier; Alberdi-Rodriguez, Joseba; Strubbe, David A; Oliveira, Micael J T; Nogueira, Fernando; Castro, Alberto; Muguerza, Javier; Arruabarrena, Agustin; Louie, Steven G; Aspuru-Guzik, Alán; Rubio, Angel; Marques, Miguel A L

    2012-06-13

    Octopus is a general-purpose density-functional theory (DFT) code, with a particular emphasis on the time-dependent version of DFT (TDDFT). In this paper we present the ongoing efforts to achieve the parallelization of octopus. We focus on the real-time variant of TDDFT, where the time-dependent Kohn-Sham equations are directly propagated in time. This approach has great potential for execution in massively parallel systems such as modern supercomputers with thousands of processors and graphics processing units (GPUs). For harvesting the potential of conventional supercomputers, the main strategy is a multi-level parallelization scheme that combines the inherent scalability of real-time TDDFT with a real-space grid domain-partitioning approach. A scalable Poisson solver is critical for the efficiency of this scheme. For GPUs, we show how using blocks of Kohn-Sham states provides the required level of data parallelism and that this strategy is also applicable for code optimization on standard processors. Our results show that real-time TDDFT, as implemented in octopus, can be the method of choice for studying the excited states of large molecular systems in modern parallel architectures.

  5. Combined effect of vacuum-packaging and oregano essential oil on the shelf-life of Mediterranean octopus (Octopus vulgaris) from the Aegean Sea stored at 4 degrees C.

    PubMed

    Atrea, I; Papavergou, A; Amvrosiadis, I; Savvaidis, I N

    2009-04-01

    The present study evaluated the use of vacuum packaging (alone) or with addition of oregano essential oil (EO), as an antimicrobial treatment for shelf-life extension of fresh Mediterranean octopus stored under refrigeration for a period of 23 days. Four different treatments were tested: A, control sample; under aerobic storage in the absence of oregano essential oil; VP, under vacuum packaging in the absence of oregano essential oil; and VO1, VO2, treated samples with oregano essential oil 0.2 and 0.4% (v/w), respectively, under VP. Of all the microorganisms enumerated, Pseudomonas spp., H2S-producing bacteria and lactic acid bacteria (LAB) were the groups that prevailed in octopus samples, irrespective of antimicrobial treatment. With regard to the chemical freshness indices determined, thiobarbituric acid (TBA) values were low in all octopus samples, as could have been expected from the low fat content of the product. Both trimethylamine nitrogen (TMA-N) and total volatile basic nitrogen (TVB-N) values of oregano treated under VP octopus samples were significantly lower compared to control samples during the entire refrigerated storage period. Based primarily on sensory evaluation (odor), the use of VP, VO1 and VO2 extended the shelf-life of fresh Mediterranean octopus by ca. 3, 11 and 20 days, respectively.

  6. Total lipids and fatty acids composition of the coastal and the deep-sea common octopus (Octopus vulgaris) populations: a comparative study.

    PubMed

    Ben-Youssef, Saoussen; Selmi, Salah; Ezzeddine-Najai, Sofia; Sadok, Saloua

    2008-01-01

    The aim of this work was to investigate biochemical differences between Octopus vulgaris caught off costal zone and from the deep-sea of the Golf of Gabès (South coast of Tunisia). In both fishing grounds, octopus total lipids constituted almost 1.5% of wet tissue showing no significant difference (p < 0.05). The percentage distribution of fatty acids was not significantly different, neither between males and females, nor between both areas. Polyunsaturated fatty acids constituted about 50 % of the total fatty acids. Docosahexaenoic (DHA; C22:6 omega 3), eicosapentaenoic (EPA; C20:5 omega 3) and the arachidonic acids (C20:4) were the most important of this group with percentages of 25, 14 and 10% respectively. The saturated fraction constituted almost 30% of the total fatty acids. The most dominant saturated fatty acids were palmitic acid (C16:0) and stearic acid (C18:0), with 18% and 7% respectively. The monounsaturated content was found to contribute only 10% of the total fatty acids. Most of the monounsaturated fat was present as oleic acid (C18:1) and palmitoleic acid (C16:1) with 2.5% and 1.5% respectively. The presence of arachidonic acid in substantial proportions with an omega 3 to omega 6 ratios of 3.9 to 1 is of special interest because of the role of cephalopods in the traditional Mediterranean diet.

  7. Gonad development during the early life of Octopus maya (Mollusca: Cephalopoda).

    PubMed

    Avila-Poveda, Omar Hernando; Colin-Flores, Rafael Francisco; Rosas, Carlos

    2009-02-01

    Gonad development during the early life of Octopus maya is described in terms of histological, morphometric, oocytes growth, and somatic-oocyte relationship data obtained from octopus cultured at the UMDI-UNAM, in Sisal, Yucatan, Mexico. This study is the first publication on gonad development during the early life of Octopus maya. A total of 83 O. maya specimens were used; their sizes ranged from 6.5 to 76 mm of total length (TL), 4 to 28 mm of dorsal mantle length (DML), 2.5 to 20 mm of ventral mantle length (VML), and 0.0180 to 7.2940 g of fixed body weight (fBW). Animals were weighed and measured only after preservation. A loss of 10% of living weight was estimated for juvenile octopuses after formalin preservation. The relation of length to weight (VML, DML, TL/fBW) pooled for both sexes had a strong positive correlation (r), as shown by a potential power function that was quite close to 1. Compound images were produced from numerous microscopic fields. The histological examination revealed that, 4 months after hatching, male octopus (24.5 mm DML and 7.2940 g fBW) were in gonad stages 2 (maturing) to 3 (mature), with spermatogonia and spermatocytes in the tubule wall and abundant spermatids and spermatozoa in the central lumen of the seminiferous tubules, suggesting the occurrence of different phases of gonad development at different maturity stages. In contrast, females (22.5 mm DML and 4.8210 g fBW) at the same time since hatching were immature (stage 1), with many oogonia, few oocytes, and germinal epithelium. This suggests that males reach maturity earlier than females, indicating a probable onset of maturity for males at around 4 months of culture or 8 g of wet body weight. Our results indicate the possibility that the size-at-weight can be recognized early with a degree of certainty that allows the sexes to be separated for culture purposes; but more detailed studies on reproduction in relation to endocrinology and nutrition are needed.

  8. Gonad development during the early life of Octopus maya (Mollusca: Cephalopoda).

    PubMed

    Avila-Poveda, Omar Hernando; Colin-Flores, Rafael Francisco; Rosas, Carlos

    2009-02-01

    Gonad development during the early life of Octopus maya is described in terms of histological, morphometric, oocytes growth, and somatic-oocyte relationship data obtained from octopus cultured at the UMDI-UNAM, in Sisal, Yucatan, Mexico. This study is the first publication on gonad development during the early life of Octopus maya. A total of 83 O. maya specimens were used; their sizes ranged from 6.5 to 76 mm of total length (TL), 4 to 28 mm of dorsal mantle length (DML), 2.5 to 20 mm of ventral mantle length (VML), and 0.0180 to 7.2940 g of fixed body weight (fBW). Animals were weighed and measured only after preservation. A loss of 10% of living weight was estimated for juvenile octopuses after formalin preservation. The relation of length to weight (VML, DML, TL/fBW) pooled for both sexes had a strong positive correlation (r), as shown by a potential power function that was quite close to 1. Compound images were produced from numerous microscopic fields. The histological examination revealed that, 4 months after hatching, male octopus (24.5 mm DML and 7.2940 g fBW) were in gonad stages 2 (maturing) to 3 (mature), with spermatogonia and spermatocytes in the tubule wall and abundant spermatids and spermatozoa in the central lumen of the seminiferous tubules, suggesting the occurrence of different phases of gonad development at different maturity stages. In contrast, females (22.5 mm DML and 4.8210 g fBW) at the same time since hatching were immature (stage 1), with many oogonia, few oocytes, and germinal epithelium. This suggests that males reach maturity earlier than females, indicating a probable onset of maturity for males at around 4 months of culture or 8 g of wet body weight. Our results indicate the possibility that the size-at-weight can be recognized early with a degree of certainty that allows the sexes to be separated for culture purposes; but more detailed studies on reproduction in relation to endocrinology and nutrition are needed. PMID:19218496

  9. Persistent Contamination of Octopuses and Mussels with Lipophilic Shellfish Toxins during Spring Dinophysis Blooms in a Subtropical Estuary

    PubMed Central

    Mafra, Luiz L.; Lopes, Daiana; Bonilauri, Vanessa C.; Uchida, Hajime; Suzuki, Toshiyuki

    2015-01-01

    This study investigates the occurrence of diarrhetic shellfish toxins (DSTs) and their producing phytoplankton species in southern Brazil, as well as the potential for toxin accumulation in co-occurring mussels (Perna perna) and octopuses (Octopus vulgaris). During the spring in 2012 and 2013, cells of Dinophysis acuminata complex were always present, sometimes at relatively high abundances (max. 1143 cells L−1), likely the main source of okadaic acid (OA) in the plankton (max. 34 ng L−1). Dinophysis caudata occurred at lower cell densities in 2013 when the lipophilic toxins pectenotoxin-2 (PTX-2) and PTX-2 seco acid were detected in plankton and mussel samples. Here, we report for the first time the accumulation of DSTs in octopuses, probably linked to the consumption of contaminated bivalves. Perna perna mussels were consistently contaminated with different DSTs (max. 42 µg kg−1), and all octopuses analyzed (n = 5) accumulated OA in different organs/tissues: digestive glands (DGs) > arms > gills > kidneys > stomach + intestine. Additionally, similar concentrations of 7-O-palmytoyl OA and 7-O-palmytoly dinophysistoxin-1 (DTX-1) were frequently detected in the hepatopancreas of P. perna and DGs of O. vulgaris. Therefore, octopuses can be considered a potential vector of DSTs to both humans and top predators such as marine mammals. PMID:26096277

  10. Persistent Contamination of Octopuses and Mussels with Lipophilic Shellfish Toxins during Spring Dinophysis Blooms in a Subtropical Estuary.

    PubMed

    Mafra, Luiz L; Lopes, Daiana; Bonilauri, Vanessa C; Uchida, Hajime; Suzuki, Toshiyuki

    2015-06-18

    This study investigates the occurrence of diarrhetic shellfish toxins (DSTs) and their producing phytoplankton species in southern Brazil, as well as the potential for toxin accumulation in co-occurring mussels (Perna perna) and octopuses (Octopus vulgaris). During the spring in 2012 and 2013, cells of Dinophysis acuminata complex were always present, sometimes at relatively high abundances (max. 1143 cells L-1), likely the main source of okadaic acid (OA) in the plankton (max. 34 ng L-1). Dinophysis caudata occurred at lower cell densities in 2013 when the lipophilic toxins pectenotoxin-2 (PTX-2) and PTX-2 seco acid were detected in plankton and mussel samples. Here, we report for the first time the accumulation of DSTs in octopuses, probably linked to the consumption of contaminated bivalves. Perna perna mussels were consistently contaminated with different DSTs (max. 42 µg kg-1), and all octopuses analyzed (n = 5) accumulated OA in different organs/tissues: digestive glands (DGs) > arms > gills > kidneys > stomach + intestine. Additionally, similar concentrations of 7-O-palmytoyl OA and 7-O-palmytoly dinophysistoxin-1 (DTX-1) were frequently detected in the hepatopancreas of P. perna and DGs of O. vulgaris. Therefore, octopuses can be considered a potential vector of DSTs to both humans and top predators such as marine mammals.

  11. Persistent Contamination of Octopuses and Mussels with Lipophilic Shellfish Toxins during Spring Dinophysis Blooms in a Subtropical Estuary.

    PubMed

    Mafra, Luiz L; Lopes, Daiana; Bonilauri, Vanessa C; Uchida, Hajime; Suzuki, Toshiyuki

    2015-06-01

    This study investigates the occurrence of diarrhetic shellfish toxins (DSTs) and their producing phytoplankton species in southern Brazil, as well as the potential for toxin accumulation in co-occurring mussels (Perna perna) and octopuses (Octopus vulgaris). During the spring in 2012 and 2013, cells of Dinophysis acuminata complex were always present, sometimes at relatively high abundances (max. 1143 cells L-1), likely the main source of okadaic acid (OA) in the plankton (max. 34 ng L-1). Dinophysis caudata occurred at lower cell densities in 2013 when the lipophilic toxins pectenotoxin-2 (PTX-2) and PTX-2 seco acid were detected in plankton and mussel samples. Here, we report for the first time the accumulation of DSTs in octopuses, probably linked to the consumption of contaminated bivalves. Perna perna mussels were consistently contaminated with different DSTs (max. 42 µg kg-1), and all octopuses analyzed (n = 5) accumulated OA in different organs/tissues: digestive glands (DGs) > arms > gills > kidneys > stomach + intestine. Additionally, similar concentrations of 7-O-palmytoyl OA and 7-O-palmytoly dinophysistoxin-1 (DTX-1) were frequently detected in the hepatopancreas of P. perna and DGs of O. vulgaris. Therefore, octopuses can be considered a potential vector of DSTs to both humans and top predators such as marine mammals. PMID:26096277

  12. Tuberculoventral neurons project to the multipolar cell area but not to the octopus cell area of the posteroventral cochlear nucleus.

    PubMed

    Wickesberg, R E; Whitlon, D; Oertel, D

    1991-11-15

    Tuberculoventral neurons in the deep layer of the dorsal cochlear nucleus (DCN) provide frequency-specific inhibition to neurons in the anteroventral cochlear nucleus (AVCN) of the mouse (Wickesberg and Oertel, '88, '90). The present experiments examine the projection from the deep DCN to the posteroventral cochlear nucleus (PVCN). Horseradish peroxidase (HRP) injections into the PVCN reveal that the multipolar cell area, but not the octopus cell area, is innervated by neurons in the deep layer of the DCN. Injections into the multipolar cell area, in the rostral and ventral PVCN, labeled neurons across the entire rostrocaudal extent of the deep DCN. The labeled tuberculoventral neurons generally lay within the band of labeled auditory nerve terminals in the DCN. Injections of HRP into the octopus cell area, in the dorsal caudal PVCN, labeled almost no cells within the band of auditory nerve fiber terminals that were labeled by the same injection. The inhibition from tuberculoventral neurons onto ventral cochlear nucleus (VCN) neurons is likely to be mediated by glycine (Wickesberg and Oertel, '90). Slices of the cochlear nuclear complex were immunolabeled by an antibody against glycine conjugated with glutaraldehyde to bovine serum albumin (Wenthold et al., '87). Glycine-like immunoreactivity was found throughout the DCN, the AVCN and the multipolar cell area, but there was little labeling in the octopus cell area. This finding provides independent evidence that tuberculoventral neurons do not innervate the octopus cell area and indicates that the octopus cell area is anatomically and functionally distinct.

  13. Microdistribution of tetrodotoxin in two species of blue-ringed octopuses (Hapalochlaena lunulata and Hapalochlaena fasciata) detected by fluorescent immunolabeling.

    PubMed

    Williams, Becky L; Stark, Michael R; Caldwell, Roy L

    2012-12-01

    Blue-ringed octopuses (genus Hapalochlaena) possess the potent neurotoxin tetrodotoxin (TTX). We examined the microdistribution of TTX in ten tissues of Hapalochlaena lunulata and Hapalochlaena fasciata by immunolabeling for fluorescent light microscopy (FLM). We visualized TTX throughout the posterior salivary gland, but the toxin was concentrated in cells lining the secretory tubules within the gland. Tetrodotoxin was present just beneath the epidermis of the integument (mantle and arms) and also concentrated in channels running through the dermis. This was suggestive of a TTX transport mechanism in the blood of the octopus, which would also explain the presence of the toxin in the blood-rich brachial hearts, gills, nephridia, and highly vascularized Needham's sac (testes contents). We also present the first report of TTX in any cephalopod outside of the genus Hapalochlaena. A specimen of Octopus bocki from French Polynesia contained a small amount of TTX in the digestive gland.

  14. Genetic structure of Octopus vulgaris (Cephalopoda, Octopodidae) in the central Mediterranean Sea inferred from the mitochondrial COIII gene.

    PubMed

    Fadhlaoui-Zid, Karima; Knittweis, Leyla; Aurelle, Didier; Nafkha, Chaala; Ezzeddine, Soufia; Fiorentino, Fabio; Ghmati, Hisham; Ceriola, Luca; Jarboui, Othman; Maltagliati, Ferruccio

    2012-01-01

    The polymorphism of the mitochondrial gene cytochrome oxidase III was studied in the Mediterranean octopus, Octopus vulgaris Cuvier, 1797. A total of 202 specimens from seven sampling sites were analysed with the aim of elucidating patterns of genetic structure in the central Mediterranean Sea and to give an insight into the phylogeny of the Octopus genus. Phylogenetic analyses showed that individuals from the central Mediterranean belong to the O. vulgaris species whose limits should nevertheless be clarified. Concerning genetic structure, two high-frequency haplotypes were present in all locations. The overall genetic divergence (Φ(ST)=0.05, P<0.05) indicated a significant genetic structuring in the study area and an AMOVA highlighted a significant break between western and eastern Mediterranean basins (Φ(CT)=0.094, P<0.05). Possible explanations for the observed patterns of genetic structuring are discussed with reference to their relevance for fisheries management.

  15. Microdistribution of tetrodotoxin in two species of blue-ringed octopuses (Hapalochlaena lunulata and Hapalochlaena fasciata) detected by fluorescent immunolabeling.

    PubMed

    Williams, Becky L; Stark, Michael R; Caldwell, Roy L

    2012-12-01

    Blue-ringed octopuses (genus Hapalochlaena) possess the potent neurotoxin tetrodotoxin (TTX). We examined the microdistribution of TTX in ten tissues of Hapalochlaena lunulata and Hapalochlaena fasciata by immunolabeling for fluorescent light microscopy (FLM). We visualized TTX throughout the posterior salivary gland, but the toxin was concentrated in cells lining the secretory tubules within the gland. Tetrodotoxin was present just beneath the epidermis of the integument (mantle and arms) and also concentrated in channels running through the dermis. This was suggestive of a TTX transport mechanism in the blood of the octopus, which would also explain the presence of the toxin in the blood-rich brachial hearts, gills, nephridia, and highly vascularized Needham's sac (testes contents). We also present the first report of TTX in any cephalopod outside of the genus Hapalochlaena. A specimen of Octopus bocki from French Polynesia contained a small amount of TTX in the digestive gland. PMID:22983011

  16. How nervous systems evolve in relation to their embodiment: what we can learn from octopuses and other molluscs.

    PubMed

    Hochner, Binyamin

    2013-01-01

    Cephalopods such as the octopus show the most advanced behavior among invertebrates, which they accomplish with an exceptionally flexible body plan. In this review I propose that the embodied organization approach, developed by roboticists to design efficient autonomous robots, is useful for understanding the evolution and development of the efficient adaptive interaction of animals with their environment, using the octopus as the leading example. The embodied organization approach explains adaptive behavior as emerging from the continuous dynamical and reciprocal physical and informational interactions between four elements: the controller, the mechanical and the sensory systems and the environment. In contrast to hierarchical organization, in embodied organization, self-organization processes can take part in the emergence of the adaptive properties. I first discuss how the embodiment concept explains covariation of body form, nervous system organization, and level of behavioral complexity using the Mollusca as an example. This is an ideal phylum to test such a qualitative correlation between body/brain/behavior, because they show the greatest variations of body plan within a single phylum. In some cases the covariation of nervous system and body structure seems to arise independently of close phylogenetic relationships. Next, I dwell on the octopus as an ideal model to test the embodiment concept within a single biological system. Here, the unusual body morphology of the octopus exposes the uniqueness of the four components comprising the octopus' embodiment. Considering together the results from behavioral, physiological, anatomical, and motor control research suggests that these four elements mutually influence each other. It is this mutual interactions and self-organization which have led to their unique evolution and development to create the unique and highly efficient octopus embodiment.

  17. Chemical Tools of Octopus maya during Crab Predation Are Also Active on Conspecifics.

    PubMed

    Pech-Puch, Dawrin; Cruz-López, Honorio; Canche-Ek, Cindy; Campos-Espinosa, Gabriela; García, Elpidio; Mascaro, Maite; Rosas, Carlos; Chávez-Velasco, Daniel; Rodríguez-Morales, Sergio

    2016-01-01

    Octopus maya is a major socio-economic resource from the Yucatán Peninsula in Mexico. In this study we report for the first time the chemical composition of the saliva of O. maya and its effect on natural prey, i.e. the blue crab (Callinectes sapidus), the crown conch snail (Melongena corona bispinosa), as well as conspecifics. Salivary posterior glands were collected from octopus caught by local fishers and extracted with water; this extract paralyzed and predigested crabs when it was injected into the third pereiopod. The water extract was fractionated by membrane ultrafiltration with a molecular weight cut-off of 3 kDa leading to a metabolic phase (>3 kDa) and a neurotoxic fraction (<3 kDa). The neurotoxic fraction injected in the crabs caused paralysis and postural changes. Crabs recovered to their initial condition within two hours, which suggests that the effects of the neurotoxic fraction were reversible. The neurotoxic fraction was also active on O. maya conspecifics, partly paralyzing and sedating them; this suggests that octopus saliva might be used among conspecifics for defense and for reduction of competition. Bioguided separation of the neurotoxic fraction by chromatography led to a paralysis fraction and a relaxing fraction. The paralyzing activity of the saliva was exerted by amino acids, while the relaxing activity was due to the presence of serotonin. Prey-handling studies revealed that O. maya punctures the eye or arthrodial membrane when predating blue crabs and uses the radula to bore through crown conch shells; these differing strategies may help O. maya to reduce the time needed to handle its prey.

  18. Chemical Tools of Octopus maya during Crab Predation Are Also Active on Conspecifics

    PubMed Central

    Pech-Puch, Dawrin; Cruz-López, Honorio; Canche-Ek, Cindy; Campos-Espinosa, Gabriela; García, Elpidio; Mascaro, Maite; Rosas, Carlos; Chávez-Velasco, Daniel; Rodríguez-Morales, Sergio

    2016-01-01

    Octopus maya is a major socio-economic resource from the Yucatán Peninsula in Mexico. In this study we report for the first time the chemical composition of the saliva of O. maya and its effect on natural prey, i.e. the blue crab (Callinectes sapidus), the crown conch snail (Melongena corona bispinosa), as well as conspecifics. Salivary posterior glands were collected from octopus caught by local fishers and extracted with water; this extract paralyzed and predigested crabs when it was injected into the third pereiopod. The water extract was fractionated by membrane ultrafiltration with a molecular weight cut-off of 3kDa leading to a metabolic phase (>3kDa) and a neurotoxic fraction (<3kDa). The neurotoxic fraction injected in the crabs caused paralysis and postural changes. Crabs recovered to their initial condition within two hours, which suggests that the effects of the neurotoxic fraction were reversible. The neurotoxic fraction was also active on O. maya conspecifics, partly paralyzing and sedating them; this suggests that octopus saliva might be used among conspecifics for defense and for reduction of competition. Bioguided separation of the neurotoxic fraction by chromatography led to a paralysis fraction and a relaxing fraction. The paralyzing activity of the saliva was exerted by amino acids, while the relaxing activity was due to the presence of serotonin. Prey-handling studies revealed that O. maya punctures the eye or arthrodial membrane when predating blue crabs and uses the radula to bore through crown conch shells; these differing strategies may help O. maya to reduce the time needed to handle its prey. PMID:26895025

  19. Chemical Tools of Octopus maya during Crab Predation Are Also Active on Conspecifics.

    PubMed

    Pech-Puch, Dawrin; Cruz-López, Honorio; Canche-Ek, Cindy; Campos-Espinosa, Gabriela; García, Elpidio; Mascaro, Maite; Rosas, Carlos; Chávez-Velasco, Daniel; Rodríguez-Morales, Sergio

    2016-01-01

    Octopus maya is a major socio-economic resource from the Yucatán Peninsula in Mexico. In this study we report for the first time the chemical composition of the saliva of O. maya and its effect on natural prey, i.e. the blue crab (Callinectes sapidus), the crown conch snail (Melongena corona bispinosa), as well as conspecifics. Salivary posterior glands were collected from octopus caught by local fishers and extracted with water; this extract paralyzed and predigested crabs when it was injected into the third pereiopod. The water extract was fractionated by membrane ultrafiltration with a molecular weight cut-off of 3 kDa leading to a metabolic phase (>3 kDa) and a neurotoxic fraction (<3 kDa). The neurotoxic fraction injected in the crabs caused paralysis and postural changes. Crabs recovered to their initial condition within two hours, which suggests that the effects of the neurotoxic fraction were reversible. The neurotoxic fraction was also active on O. maya conspecifics, partly paralyzing and sedating them; this suggests that octopus saliva might be used among conspecifics for defense and for reduction of competition. Bioguided separation of the neurotoxic fraction by chromatography led to a paralysis fraction and a relaxing fraction. The paralyzing activity of the saliva was exerted by amino acids, while the relaxing activity was due to the presence of serotonin. Prey-handling studies revealed that O. maya punctures the eye or arthrodial membrane when predating blue crabs and uses the radula to bore through crown conch shells; these differing strategies may help O. maya to reduce the time needed to handle its prey. PMID:26895025

  20. Composition and metabolism of phospholipids in Octopus vulgaris and Sepia officinalis hatchlings.

    PubMed

    Reis, Diana B; Acosta, Nieves G; Almansa, Eduardo; Tocher, Douglas R; Andrade, José P; Sykes, António V; Rodríguez, Covadonga

    2016-10-01

    The objective of the present study was to characterise the fatty acid (FA) profiles of the major phospholipids, of Octopus vulgaris and Sepia officinalis hatchlings, namely phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylinositol (PI) and phosphatidylethanolamine (PE); and to evaluate the capability of both cephalopod species on dietary phospholipid remodelling. Thus, O. vulgaris and S. officinalis hatchlings were in vivo incubated with 0.3μM of L-∝-1-palmitoyl-2-[1-(14)C]arachidonyl-PC or L-∝-1-palmitoyl-2-[1-(14)C]arachidonyl-PE. Octopus and cuttlefish hatchlings phospholipids showed a characteristic FA profiles with PC presenting high contents of 16:0 and 22:6n-3 (DHA); PS having high 18:0, DHA and 20:5n-3 (EPA); PI a high content of saturated FA; and PE showing high contents of DHA and EPA. Interestingly, the highest content of 20:4n-6 (ARA) was found in PE rather than PI. Irrespective of the phospholipid in which [1-(14)C]ARA was initially bound (either PC or PE), the esterification pattern of [1-(14)C]ARA in octopus lipids was similar to that found in their tissues with high esterification of this FA into PE. In contrast, in cuttlefish hatchlings [1-(14)C]ARA was mainly recovered in the same phospholipid that was provided. These results showed a characteristic FA profiles in the major phospholipids of the two species, as well as a contrasting capability to remodel dietary phospholipids, which may suggest a difference in phospholipase activities.

  1. What drives seasonal fluctuations of body condition in a semelparous income breeder octopus?

    NASA Astrophysics Data System (ADS)

    Quetglas, Antoni; Ordines, Francesc; Valls, Maria

    2011-09-01

    The vast majority of modern cephalopods is single-season breeders, or semelparous in the strict sense, that die soon after the reproduction takes place. Individual body condition in these marine invertebrates is expected to be highly affected by reproduction because: 1) the gonad weight of females, which represents <1% of body weight when immature, increases up to 20-50% during maturation; and 2) octopus females reduce or even cease their food intake during breeding. Based on this expectation, we analysed the interrelationship between condition and reproduction in the temperate octopus Eledone cirrhosa. Results from a previous work using biochemical analyses showed that reproduction in this species is not fuelled by stored reserves (capital breeder), but by food intakes (income breeder). Since income breeders depend strongly on food resources, the effect of several environmental variables related to food availability such as primary production, sea temperature (ST) and river discharges were also analysed. Condition showed a marked intrannual cycle independently of the sex and, noteworthy, the maturity stage. Given that immature individuals are not expected to display seasonal fluctuations in body condition related to maturation, these results preclude reproduction as a driving factor for the observed circannual cycle. Condition was significantly correlated with all the environmental variables analysed, except with ST at the depths where the species lives. Although this last result also precludes concurrent ST as a driving factor of body condition, those correlations suggest that condition might display an intrinsic seasonal cycle, as many other life-history traits in most species such as reproduction, migration or moulting. Finally, there also remains the possibility that condition in this octopus species is determined genetically, as has been reported in recent studies across different taxonomical groups.

  2. Composition and metabolism of phospholipids in Octopus vulgaris and Sepia officinalis hatchlings.

    PubMed

    Reis, Diana B; Acosta, Nieves G; Almansa, Eduardo; Tocher, Douglas R; Andrade, José P; Sykes, António V; Rodríguez, Covadonga

    2016-10-01

    The objective of the present study was to characterise the fatty acid (FA) profiles of the major phospholipids, of Octopus vulgaris and Sepia officinalis hatchlings, namely phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylinositol (PI) and phosphatidylethanolamine (PE); and to evaluate the capability of both cephalopod species on dietary phospholipid remodelling. Thus, O. vulgaris and S. officinalis hatchlings were in vivo incubated with 0.3μM of L-∝-1-palmitoyl-2-[1-(14)C]arachidonyl-PC or L-∝-1-palmitoyl-2-[1-(14)C]arachidonyl-PE. Octopus and cuttlefish hatchlings phospholipids showed a characteristic FA profiles with PC presenting high contents of 16:0 and 22:6n-3 (DHA); PS having high 18:0, DHA and 20:5n-3 (EPA); PI a high content of saturated FA; and PE showing high contents of DHA and EPA. Interestingly, the highest content of 20:4n-6 (ARA) was found in PE rather than PI. Irrespective of the phospholipid in which [1-(14)C]ARA was initially bound (either PC or PE), the esterification pattern of [1-(14)C]ARA in octopus lipids was similar to that found in their tissues with high esterification of this FA into PE. In contrast, in cuttlefish hatchlings [1-(14)C]ARA was mainly recovered in the same phospholipid that was provided. These results showed a characteristic FA profiles in the major phospholipids of the two species, as well as a contrasting capability to remodel dietary phospholipids, which may suggest a difference in phospholipase activities. PMID:27267253

  3. Liquid-crystalline octopus dendrimers: block molecules with unusual mesophase morphologies.

    PubMed

    Gehringer, Lionel; Bourgogne, Cyril; Guillon, Daniel; Donnio, Bertrand

    2004-03-31

    The synthesis and the mesomorphic properties of several new main-chain liquid-crystalline dendrimers, thereafter designated as octopus dendrimers in accordance with their eight sidearms, are reported. In these dendritic systems, the arborescence is ensured by anisotropic segments, acting as branching cells with a double multiplicity, which are incorporated at every node of the dendritic architecture. In such a way, these compounds radically differ from the classical end-functionalized liquid-crystalline dendrimers, the most commonly reported systems. Following our previous report on purely homolithic systems, that is, the building blocks constituting the dendritic matrix are all identical, several heterolithic systems made of different anisotropic blocks have been prepared. The dendritic branches and corresponding dendrimers were synthesized using a modular construction. Polarized optical microscopy and X-ray diffraction studies showed that all of these new octopus dendrimers exhibit either smectic-like or columnar phases with novel morphologies, the nature of the mesophases depending on the number of terminal chains attached to the peripheral groups. The mesomorphism of these heterolithic dendrimers is discussed in terms of their intrinsic architecture and compared to the analogous homolithic octopus systems. Models for the molecular organizations within both the smectic and the columnar phases are proposed on the basis of small Bragg angle X-ray diffraction studies and are supported by molecular modelizations. Moreover, this study showed that the mesophase stability is very sensitive to the nature and to the mutual arrangement (the spatial location) of the mesogenic segments within the dendritic matrix, illustrating the intimate relationships existing between the mesomorphic properties and the molecular architecture of these dendrimers.

  4. Indole Alkaloids from the Sea Anemone Heteractis aurora and Homarine from Octopus cyanea.

    PubMed

    Shaker, Kamel H; Göhl, Matthias; Müller, Tobias; Seifert, Karlheinz

    2015-11-01

    The two new indole alkaloids 2-amino-1,5-dihydro-5-(1H-indol-3-ylmethyl)-4H-imidazol-4-one (1), 2-amino-5-[(6-bromo-1H-indol-3-yl)methyl]-3,5-dihydro-3-methyl-4H-imidazol-4-one (2), and auramine (3) have been isolated from the sea anemone Heteractis aurora. Both indole alkaloids were synthesized for the confirmation of the structures. Homarine (4), along with uracil (5), hypoxanthine (6), and inosine (7) have been obtained from Octopus cyanea. PMID:26567952

  5. The complete mitochondrial genome of Octopus conispadiceus (Sasaki, 1917) (Cephalopoda: Octopodidae).

    PubMed

    Ma, Yuanyuan; Zheng, Xiaodong; Cheng, Rubin; Li, Qi

    2016-01-01

    In this paper, we determined the complete mitochondrial genome of Octopus conispadiceus (Cephalopoda: Octopodidae). The whole mitogenome of O. conispadiceus is 16,027 basepairs (bp) in length with a base composition of 41.4% A, 34.8% T, 16.1% C, 7.7% G and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and a major non-coding region (MNR). The gene arrangements of O. conispadiceus showed remarkable similarity to that of O. vulgaris, Amphioctopus fangsiao, Cistopus chinensis and C. taiwanicus. PMID:24971549

  6. Stereotypical reaching movements of the octopus involve both bend propagation and arm elongation.

    PubMed

    Hanassy, S; Botvinnik, A; Flash, T; Hochner, B

    2015-06-01

    The bend propagation involved in the stereotypical reaching movement of the octopus arm has been extensively studied. While these studies have analyzed the kinematics of bend propagation along the arm during its extension, possible length changes have been ignored. Here, the elongation profiles of the reaching movements of Octopus vulgaris were assessed using three-dimensional reconstructions. The analysis revealed that, in addition to bend propagation, arm extension movements involve elongation of the proximal part of the arm, i.e., the section from the base of the arm to the propagating bend. The elongations are quite substantial and highly variable, ranging from an average strain along the arm of -0.12 (i.e. shortening) up to 1.8 at the end of the movement (0.57 ± 0.41, n = 64 movements, four animals). Less variability was discovered in an additional set of experiments on reaching movements (0.64 ± 0.28, n = 30 movements, two animals), where target and octopus positions were kept more stationary. Visual observation and subsequent kinematic analysis suggest that the reaching movements can be broadly segregated into two groups. The first group involves bend propagation beginning at the base of the arm and propagating towards the arm tip. In the second, the bend is formed or present more distally and reaching is achieved mainly by elongation and straightening of the segment proximal to the bend. Only in the second type of movements is elongation significantly positively correlated with the distance of the bend from the target. We suggest that reaching towards a target is generated by a combination of both propagation of a bend along the arm and arm elongation. These two motor primitives may be combined to create a broad spectrum of reaching movements. The dynamical model, which recapitulates the biomechanics of the octopus muscular hydrostatic arm, suggests that achieving the observed elongation requires an extremely low ratio of longitudinal to transverse muscle

  7. Indole Alkaloids from the Sea Anemone Heteractis aurora and Homarine from Octopus cyanea.

    PubMed

    Shaker, Kamel H; Göhl, Matthias; Müller, Tobias; Seifert, Karlheinz

    2015-11-01

    The two new indole alkaloids 2-amino-1,5-dihydro-5-(1H-indol-3-ylmethyl)-4H-imidazol-4-one (1), 2-amino-5-[(6-bromo-1H-indol-3-yl)methyl]-3,5-dihydro-3-methyl-4H-imidazol-4-one (2), and auramine (3) have been isolated from the sea anemone Heteractis aurora. Both indole alkaloids were synthesized for the confirmation of the structures. Homarine (4), along with uracil (5), hypoxanthine (6), and inosine (7) have been obtained from Octopus cyanea.

  8. Stereotypical reaching movements of the octopus involve both bend propagation and arm elongation.

    PubMed

    Hanassy, S; Botvinnik, A; Flash, T; Hochner, B

    2015-05-13

    The bend propagation involved in the stereotypical reaching movement of the octopus arm has been extensively studied. While these studies have analyzed the kinematics of bend propagation along the arm during its extension, possible length changes have been ignored. Here, the elongation profiles of the reaching movements of Octopus vulgaris were assessed using three-dimensional reconstructions. The analysis revealed that, in addition to bend propagation, arm extension movements involve elongation of the proximal part of the arm, i.e., the section from the base of the arm to the propagating bend. The elongations are quite substantial and highly variable, ranging from an average strain along the arm of -0.12 (i.e. shortening) up to 1.8 at the end of the movement (0.57 ± 0.41, n = 64 movements, four animals). Less variability was discovered in an additional set of experiments on reaching movements (0.64 ± 0.28, n = 30 movements, two animals), where target and octopus positions were kept more stationary. Visual observation and subsequent kinematic analysis suggest that the reaching movements can be broadly segregated into two groups. The first group involves bend propagation beginning at the base of the arm and propagating towards the arm tip. In the second, the bend is formed or present more distally and reaching is achieved mainly by elongation and straightening of the segment proximal to the bend. Only in the second type of movements is elongation significantly positively correlated with the distance of the bend from the target. We suggest that reaching towards a target is generated by a combination of both propagation of a bend along the arm and arm elongation. These two motor primitives may be combined to create a broad spectrum of reaching movements. The dynamical model, which recapitulates the biomechanics of the octopus muscular hydrostatic arm, suggests that achieving the observed elongation requires an extremely low ratio of longitudinal to transverse muscle

  9. The complete mitochondrial genome of Octopus conispadiceus (Sasaki, 1917) (Cephalopoda: Octopodidae).

    PubMed

    Ma, Yuanyuan; Zheng, Xiaodong; Cheng, Rubin; Li, Qi

    2016-01-01

    In this paper, we determined the complete mitochondrial genome of Octopus conispadiceus (Cephalopoda: Octopodidae). The whole mitogenome of O. conispadiceus is 16,027 basepairs (bp) in length with a base composition of 41.4% A, 34.8% T, 16.1% C, 7.7% G and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and a major non-coding region (MNR). The gene arrangements of O. conispadiceus showed remarkable similarity to that of O. vulgaris, Amphioctopus fangsiao, Cistopus chinensis and C. taiwanicus.

  10. A multilevel approach to examining cephalopod growth using Octopus pallidus as a model.

    PubMed

    Semmens, Jayson; Doubleday, Zoë; Hoyle, Kate; Pecl, Gretta

    2011-08-15

    Many aspects of octopus growth dynamics are poorly understood, particularly in relation to sub-adult or adult growth, muscle fibre dynamics and repro-somatic investment. The growth of 5 month old Octopus pallidus cultured in the laboratory was investigated under three temperature regimes over a 12 week period: seasonally increasing temperatures (14-18°C); seasonally decreasing temperatures (18-14°C); and a constant temperature mid-way between seasonal peaks (16°C). Differences in somatic growth at the whole-animal level, muscle tissue structure and rate of gonad development were investigated. Continuous exponential growth was observed, both at a group and at an individual level, and there was no detectable effect of temperature on whole-animal growth rate. Juvenile growth rate (from 1 to 156 days) was also monitored prior to the controlled experiment; exponential growth was observed, but at a significantly faster rate than in the older experimental animals, suggesting that O. pallidus exhibit a double-exponential two-phase growth pattern. There was considerable variability in size-at-age even between individuals growing under identical thermal regimes. Animals exposed to seasonally decreasing temperatures exhibited a higher rate of gonad development compared with animals exposed to increasing temperatures; however, this did not coincide with a detectable decline in somatic growth rate or mantle condition. The ongoing production of new mitochondria-poor and mitochondria-rich muscle fibres (hyperplasia) was observed, indicated by a decreased or stable mean muscle fibre diameter concurrent with an increase in whole-body size. Animals from both seasonal temperature regimes demonstrated higher rates of new mitochondria-rich fibre generation relative to those from the constant temperature regime, but this difference was not reflected in a difference in growth rate at the whole-body level. This is the first study to record ongoing hyperplasia in the muscle tissue of an

  11. Microsatellite marker isolation and development for the giant Pacific Octopus (Enteroctopus dofleini)

    USGS Publications Warehouse

    Toussaint, Rebecca K.; Sage, G. Kevin; Talbot, Sandra L.; Scheel, David

    2012-01-01

    We isolated and developed 18 novel microsatellite markers for the giant Pacific octopus (Enteroctopus dofleini) and examined them for 31 individuals from Prince William Sound (PWS), Alaska. These loci displayed moderate levels of allelic diversity (averaging 11 alleles per locus) and heterozygosity (averaging 65%). Seven loci deviated from Hardy–Weinberg Equilibrium (HWE) due to heterozygote deficiency for the PWS population, although deviations were not observed for all these loci in other populations, suggesting the PWS population is not in mutation-drift equilibrium. These novel microsatellite loci yielded sufficient genetic diversity for potential use in population genetics, individual identification, and parentage studies.

  12. 76 FR 55276 - Fisheries of the Exclusive Economic Zone Off Alaska; Octopus in the Bering Sea and Aleutian Islands

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-07

    ... of the BSAI (76 FR 11139, March 1, 2011) and an apportionment from the non-specified reserve of groundfish (76 FR 17360, March 29, 2011). In accordance with Sec. 679.20(d)(2), the Administrator, Alaska... Economic Zone Off Alaska; Octopus in the Bering Sea and Aleutian Islands AGENCY: National Marine...

  13. 76 FR 17360 - Fisheries of the Exclusive Economic Zone Off Alaska; Octopus in the Bering Sea and Aleutian...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-29

    ... groundfish in the BSAI (76 FR 11139, March 1, 2011). The harvest specification for octopus included in the final 2011 and 2012 harvest specifications for groundfish in the BSAI (76 FR 11139, March 1, 2011) for... (76 FR 11139, March 1, 2011). In accordance with Sec. 679.20(a)(3) the Regional Administrator,...

  14. Tools and methods for experimental in-vivo measurement and biomechanical characterization of an Octopus vulgaris arm.

    PubMed

    Margheri, Laura; Mazzolai, Barbara; Cianchetti, Matteo; Dario, Paolo; Laschi, Cecilia

    2009-01-01

    This work illustrates new tools and methods for an in vivo and direct, but non-invasive, measurement of an octopus arm mechanical properties. The active elongation (longitudinal stretch) and the pulling force capability are measured on a specimen of Octopus vulgaris in order to quantitatively characterize the parameters describing the arm mechanics, for biomimetic design purposes. The novel approach consists of observing and measuring a living octopus with minimally invasive methods, which allow the animal to move with its complete ability. All tools are conceived in order to create a collaborative interaction with the animal for the acquisition of active measures. The data analysis is executed taking into account the presence of an intrinsic error due to the mobility of the subject and the aquatic environment. Using a system of two synchronized high-speed high-resolution cameras and purpose-made instruments, the maximum elongation of an arm and its rest length (when all muscles fibres are relaxed during propulsion movement) are measured and compared to define the longitudinal stretch, with the impressive average result of 194%. With a similar setup integrated with a force sensor, the pulling force capability is measured as a function of grasp point position along the arm. The measured parameters are used as real specifications for the design of an octopus-like arm with a biomimetic approach. PMID:19965276

  15. 76 FR 3044 - Fisheries of the Exclusive Economic Zone Off Alaska; Sculpins, Sharks, Squid, and Octopus in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-19

    ... harvest specifications for groundfish of the GOA (75 FR 11749, March 12, 2010). In accordance with Sec... Economic Zone Off Alaska; Sculpins, Sharks, Squid, and Octopus in the Gulf of Alaska AGENCY: National...: Temporary rule; closure. SUMMARY: NMFS is prohibiting directed fishing for sculpins, sharks, squid,...

  16. A soft body as a reservoir: case studies in a dynamic model of octopus-inspired soft robotic arm.

    PubMed

    Nakajima, Kohei; Hauser, Helmut; Kang, Rongjie; Guglielmino, Emanuele; Caldwell, Darwin G; Pfeifer, Rolf

    2013-01-01

    The behaviors of the animals or embodied agents are characterized by the dynamic coupling between the brain, the body, and the environment. This implies that control, which is conventionally thought to be handled by the brain or a controller, can partially be outsourced to the physical body and the interaction with the environment. This idea has been demonstrated in a number of recently constructed robots, in particular from the field of "soft robotics". Soft robots are made of a soft material introducing high-dimensionality, non-linearity, and elasticity, which often makes the robots difficult to control. Biological systems such as the octopus are mastering their complex bodies in highly sophisticated manners by capitalizing on their body dynamics. We will demonstrate that the structure of the octopus arm cannot only be exploited for generating behavior but also, in a sense, as a computational resource. By using a soft robotic arm inspired by the octopus we show in a number of experiments how control is partially incorporated into the physical arm's dynamics and how the arm's dynamics can be exploited to approximate non-linear dynamical systems and embed non-linear limit cycles. Future application scenarios as well as the implications of the results for the octopus biology are also discussed.

  17. Transcriptional and Biochemical Effects of Cadmium and Manganese on the Defense System of Octopus vulgaris Paralarvae

    PubMed Central

    Salamone, Monica; Mazzola, Salvatore; Cuttitta, Angela

    2015-01-01

    Due to anthropogenic activities the relative concentrations of cadmium and manganese have increased in the marine environment. Cephalopods are able to accumulate such metals and, as inhabitant of coastal waters, Octopus vulgaris is continuously exposed to anthropogenic activities. Since no study is available on the effects of heavy metals at molecular level in developing octopuses, herein we exposed 1-day-old paralarvae for 24 h to 10, 100, and 1000 μg/L of CdCl2 or MnCl2. Cd exerted a concentration-dependent inhibition of survival and a reduction in growth rate was shown while Mn exposure did not affect the survival rate even at the highest concentrations. Gene expression profiles of hsp70, sod, cat, and gst genes were analyzed by quantitative real-time PCR and defined patterns of transcription were observed. Moreover posttranscriptional analyses were also performed suggesting the impairment of metabolic functions, under strong oxidative conditions (as occurred in paralarvae exposed to Cd) or the complete detoxification events (as occurred in paralarvae exposed to Mn). PMID:25705660

  18. Octopus vulgaris (Cuvier, 1797) in the Mediterranean Sea: Genetic Diversity and Population Structure

    PubMed Central

    De Luca, Daniele; Catanese, Gaetano; Procaccini, Gabriele; Fiorito, Graziano

    2016-01-01

    The common octopus, Octopus vulgaris Cuvier 1797, is a largely exploited cephalopod species in the Mediterranean Sea and the Atlantic Ocean, as well as along the coasts of Africa, Brazil and Japan, where its taxonomic identity is still debated. The assessment of its genetic structure is a pressing need to correctly manage the resource and to avoid overfishing and collapsing of local stocks. Here we analysed genetic variation and population structure of O. vulgaris using thirteen microsatellite loci in seven sampling localities from the Mediterranean Sea and one from the Atlantic Ocean. We also used a DNA barcoding approach by COI gene fragment to understand the phylogenetic relationships among the specimens here investigated and the ones whose sequences are available in literature. Our results reveal high levels of allelic richness and moderate heterozygosity in all samples investigated, and a pronounced differentiation of the Atlantic and Sicilian specimens. This latter aspect seems to support the isolation of the biota within the Strait of Messina. A certain degree of differentiation was detected among the other geographic samples within the Mediterranean Sea, which is more compatible with an island model than isolation by distance. The occurrence of null alleles affected more genetic diversity indices than population structure estimations. This study provides new insights about the genetic diversity and structure of O. vulgaris in the area of interest, which can be used as guidelines for a fisheries management perspective. PMID:26881847

  19. Octopus lipid and vitamin E composition: interspecies, interorigin, and nutritional variability.

    PubMed

    Torrinha, Alvaro; Cruz, Rebeca; Gomes, Filipa; Mendes, Eulália; Casal, Susana; Morais, Simone

    2014-08-20

    Octopus vulgaris, Octopus maya, and Eledone cirrhosa from distinct marine environments [Northeast Atlantic (NEA), Northwest Atlantic (NWA), Eastern Central Atlantic, Western Central Atlantic (WCA), Pacific Ocean, and Mediterranean Sea] were characterized regarding their lipid and vitamin E composition. These species are those commercially more relevant worldwide. Significant interspecies and interorigin differences were observed. Unsaturated fatty acids account for more than 65% of total fatty acids, mostly ω-3 PUFA due to docosahexaenoic (18.4-29.3%) and eicosapentanoic acid (11.4-23.9%) contributions. The highest ω-3 PUFA amounts and ω-3/ω-6 ratios were quantified in the heaviest specimens, O. vulgaris from NWA, with high market price, and simultaneously in the lowest graded samples, E. cirrhosa from NEA, of reduced dimensions. Although having the highest cholesterol contents, E. cirrhosa from NEA and O. maya from WCA have also higher protective fatty acid indexes. Chemometric discrimination allowed clustering the selected species and several origins based on lipid and vitamin E profiles.

  20. Transcriptional and biochemical effects of cadmium and manganese on the defense system of Octopus vulgaris paralarvae.

    PubMed

    Nicosia, Aldo; Salamone, Monica; Mazzola, Salvatore; Cuttitta, Angela

    2015-01-01

    Due to anthropogenic activities the relative concentrations of cadmium and manganese have increased in the marine environment. Cephalopods are able to accumulate such metals and, as inhabitant of coastal waters, Octopus vulgaris is continuously exposed to anthropogenic activities. Since no study is available on the effects of heavy metals at molecular level in developing octopuses, herein we exposed 1-day-old paralarvae for 24 h to 10, 100, and 1000 μg/L of CdCl2 or MnCl2. Cd exerted a concentration-dependent inhibition of survival and a reduction in growth rate was shown while Mn exposure did not affect the survival rate even at the highest concentrations. Gene expression profiles of hsp70, sod, cat, and gst genes were analyzed by quantitative real-time PCR and defined patterns of transcription were observed. Moreover posttranscriptional analyses were also performed suggesting the impairment of metabolic functions, under strong oxidative conditions (as occurred in paralarvae exposed to Cd) or the complete detoxification events (as occurred in paralarvae exposed to Mn).

  1. Octopus vulgaris (Cuvier, 1797) in the Mediterranean Sea: Genetic Diversity and Population Structure.

    PubMed

    De Luca, Daniele; Catanese, Gaetano; Procaccini, Gabriele; Fiorito, Graziano

    2016-01-01

    The common octopus, Octopus vulgaris Cuvier 1797, is a largely exploited cephalopod species in the Mediterranean Sea and the Atlantic Ocean, as well as along the coasts of Africa, Brazil and Japan, where its taxonomic identity is still debated. The assessment of its genetic structure is a pressing need to correctly manage the resource and to avoid overfishing and collapsing of local stocks. Here we analysed genetic variation and population structure of O. vulgaris using thirteen microsatellite loci in seven sampling localities from the Mediterranean Sea and one from the Atlantic Ocean. We also used a DNA barcoding approach by COI gene fragment to understand the phylogenetic relationships among the specimens here investigated and the ones whose sequences are available in literature. Our results reveal high levels of allelic richness and moderate heterozygosity in all samples investigated, and a pronounced differentiation of the Atlantic and Sicilian specimens. This latter aspect seems to support the isolation of the biota within the Strait of Messina. A certain degree of differentiation was detected among the other geographic samples within the Mediterranean Sea, which is more compatible with an island model than isolation by distance. The occurrence of null alleles affected more genetic diversity indices than population structure estimations. This study provides new insights about the genetic diversity and structure of O. vulgaris in the area of interest, which can be used as guidelines for a fisheries management perspective. PMID:26881847

  2. Transcriptional and biochemical effects of cadmium and manganese on the defense system of Octopus vulgaris paralarvae.

    PubMed

    Nicosia, Aldo; Salamone, Monica; Mazzola, Salvatore; Cuttitta, Angela

    2015-01-01

    Due to anthropogenic activities the relative concentrations of cadmium and manganese have increased in the marine environment. Cephalopods are able to accumulate such metals and, as inhabitant of coastal waters, Octopus vulgaris is continuously exposed to anthropogenic activities. Since no study is available on the effects of heavy metals at molecular level in developing octopuses, herein we exposed 1-day-old paralarvae for 24 h to 10, 100, and 1000 μg/L of CdCl2 or MnCl2. Cd exerted a concentration-dependent inhibition of survival and a reduction in growth rate was shown while Mn exposure did not affect the survival rate even at the highest concentrations. Gene expression profiles of hsp70, sod, cat, and gst genes were analyzed by quantitative real-time PCR and defined patterns of transcription were observed. Moreover posttranscriptional analyses were also performed suggesting the impairment of metabolic functions, under strong oxidative conditions (as occurred in paralarvae exposed to Cd) or the complete detoxification events (as occurred in paralarvae exposed to Mn). PMID:25705660

  3. Octopus lipid and vitamin E composition: interspecies, interorigin, and nutritional variability.

    PubMed

    Torrinha, Alvaro; Cruz, Rebeca; Gomes, Filipa; Mendes, Eulália; Casal, Susana; Morais, Simone

    2014-08-20

    Octopus vulgaris, Octopus maya, and Eledone cirrhosa from distinct marine environments [Northeast Atlantic (NEA), Northwest Atlantic (NWA), Eastern Central Atlantic, Western Central Atlantic (WCA), Pacific Ocean, and Mediterranean Sea] were characterized regarding their lipid and vitamin E composition. These species are those commercially more relevant worldwide. Significant interspecies and interorigin differences were observed. Unsaturated fatty acids account for more than 65% of total fatty acids, mostly ω-3 PUFA due to docosahexaenoic (18.4-29.3%) and eicosapentanoic acid (11.4-23.9%) contributions. The highest ω-3 PUFA amounts and ω-3/ω-6 ratios were quantified in the heaviest specimens, O. vulgaris from NWA, with high market price, and simultaneously in the lowest graded samples, E. cirrhosa from NEA, of reduced dimensions. Although having the highest cholesterol contents, E. cirrhosa from NEA and O. maya from WCA have also higher protective fatty acid indexes. Chemometric discrimination allowed clustering the selected species and several origins based on lipid and vitamin E profiles. PMID:25087929

  4. OCTOPUS--a church-based sex education program for teens and parents.

    PubMed

    Jacknik, M; Isberner, F; Gumerman, S; Hayworth, R; Braunling-McMorrow, D

    1984-01-01

    OCTOPUS is the acronym for a rural, church-based sex education program for teens and parents. The tentacles symbolize the agencies and individuals involved in this multi-faceted community outreach program designed to promote "Open Communication Regarding Teenagers Or Parents Understanding of Sexuality." Its purpose was to establish a forum for family discussion within a church setting to enhance communication skills, convey factual information, and cultivate the development of a decision-making process to help parents help their teenagers acquire appropriate morals and values. The OCTOPUS program was a team effort comprised of nurses, health educators, and counselors with experience serving adolescents, ministers who sought to integrate religious views with sex education, and church and community members interested in improving dialogue between parents and teenagers about sexuality. The team developed a comprehensive yet flexible program that could be modified to meet each church's preferences. Generally, the topics were arranged into four two-hour sessions. Presentation methods included a combination of lectures, films, and pamphlets. Large and small group discussions were used for clarification and communication skills development. While the results of this program were not quantifiable, feedback from four churches and one-hundred participants has been highly favorable.

  5. Self-Assembly of Octopus Nanoparticles into Pre-Programmed Finite Clusters

    NASA Astrophysics Data System (ADS)

    Halverson, Jonathan; Tkachenko, Alexei

    2012-02-01

    The precise control of the spatial arrangement of nanoparticles (NP) is often required to take full advantage of their novel optical and electronic properties. NPs have been shown to self-assemble into crystalline structures using either patchy surface regions or complementary DNA strands to direct the assembly. Due to a lack of specificity of the interactions these methods lead to only a limited number of structures. An emerging approach is to bind ssDNA at specific sites on the particle surface making so-called octopus NPs. Using octopus NPs we investigate the inverse problem of the self-assembly of finite clusters. That is, for a given target cluster (e.g., arranging the NPs on the vertices of a dodecahedron) what are the minimum number of complementary DNA strands needed for the robust self-assembly of the cluster from an initially homogeneous NP solution? Based on the results of Brownian dynamics simulations we have compiled a set of design rules for various target clusters including cubes, pyramids, dodecahedrons and truncated icosahedrons. Our approach leads to control over the kinetic pathway and has demonstrated nearly perfect yield of the target.

  6. Differential proteins of the optic ganglion in octopus vulgaris under methanol stress revealed using proteomics.

    PubMed

    Huang, Lin; Huang, Qing-Yu; Chen, Hai-Bin; Huang, Fu-Sheng; Huang, He-Qing

    2011-10-01

    An analytical approach using the two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) technique separated the proteome from the optic ganglia of Octopus vulgaris (OVOG). Approximately 600 protein spots were detected from the extraction when applying 150 μg protein to a 2D-PAGE gel in the pH range 5.0-8.0. Compared to the control, significant changes of 18 protein spots were observed in OVOG under the stress of native seawater containing 2% methanol for 72 h. Among these spots, we found that eight were down-regulated and ten were up-regulated in the gels, which were further identified using both peptide mass fingerprinting and database searches. Significant proteins such as glyceraldehyde-3-phosphate dehydrogenase, alpha subunit of succinyl-CoA synthetase, alcohol dehydrogenase, and long-chain specific acyl-CoA dehydrogenase were up-regulated proteins, whereas putative ABC transporter was a down -regulated protein. These differential proteins at the level of subcellular localization were further classified using LOCtree software with a hierarchical system of support vector machines. We found that most of the differential proteins in the gel could be identified as mitochondrial proteins, suggesting that these protective or marker proteins might help to prevent methanol poisoning via the mitochondria in the optical ganglia. The results indicated that both beta-tubulin and beta-actin were potential biomarkers as up-regulated proteins for monitoring methanol toxicosis associated with fish foods such as octopus and shark.

  7. How does the blue-ringed octopus (Hapalochlaena lunulata) flash its blue rings?

    PubMed

    Mäthger, Lydia M; Bell, George R R; Kuzirian, Alan M; Allen, Justine J; Hanlon, Roger T

    2012-11-01

    The blue-ringed octopus (Hapalochlaena lunulata), one of the world's most venomous animals, has long captivated and endangered a large audience: children playing at the beach, divers turning over rocks, and biologists researching neurotoxins. These small animals spend much of their time in hiding, showing effective camouflage patterns. When disturbed, the octopus will flash around 60 iridescent blue rings and, when strongly harassed, bite and deliver a neurotoxin that can kill a human. Here, we describe the flashing mechanism and optical properties of these rings. The rings contain physiologically inert multilayer reflectors, arranged to reflect blue-green light in a broad viewing direction. Dark pigmented chromatophores are found beneath and around each ring to enhance contrast. No chromatophores are above the ring; this is unusual for cephalopods, which typically use chromatophores to cover or spectrally modify iridescence. The fast flashes are achieved using muscles under direct neural control. The ring is hidden by contraction of muscles above the iridophores; relaxation of these muscles and contraction of muscles outside the ring expose the iridescence. This mechanism of producing iridescent signals has not previously been reported in cephalopods and we suggest that it is an exceptionally effective way to create a fast and conspicuous warning display.

  8. Quantitative elemental imaging of octopus stylets using PIXE and the nuclear microprobe

    NASA Astrophysics Data System (ADS)

    Doubleday, Zoë; Belton, David; Pecl, Gretta; Semmens, Jayson

    2008-01-01

    By utilising targeted microprobe technology, the analysis of elements incorporated within the hard bio-mineralised structures of marine organisms has provided unique insights into the population biology of many species. As hard structures grow, elements from surrounding waters are incorporated effectively providing a natural 'tag' that is often unique to the animal's particular location or habitat. The spatial distribution of elements within octopus stylets was investigated, using the nuclear microprobe, to assess their potential for determining dispersal and population structure in octopus populations. Proton Induced X-ray Emission (PIXE) was conducted using the Dynamic Analysis method and GeoPIXE software package, which produced high resolution, quantitative elemental maps of whole stylet cross-sections. Ten elements were detected within the stylets which were heterogeneously distributed throughout the microstructure. Although Ca decreased towards the section edge, this trend was consistent between individuals and remained homogeneous in the inner region of the stylet, and thus appears a suitable internal standard for future microprobe analyses. Additional analyses used to investigate the general composition of the stylet structure suggested that they are amorphous and largely organic, however, there was some evidence of phosphatic mineralisation. In conclusion, this study indicates that stylets are suitable for targeted elemental analysis, although this is currently limited to the inner hatch region of the microstructure.

  9. Inter-cohort growth for three tropical resources: tilapia, octopus and lobster.

    PubMed

    Velázquez-Abunader, Iván; Gómez-Muñoz, Victor Manuel; Salas, Silvia; Ruiz-Velazco, Javier M J

    2015-09-01

    Growth parameters are an important component for the stock assessment of exploited aquatic species. However, it is often difficult to apply direct methods to estimate growth and to analyse the differences between males and females, particularly in tropical areas. The objective of this study was to analyse the inter-cohort growth of three tropical resources and discuss the possible fisheries management implications. A simple method was used to compare individual growth curves obtained from length frequency distribution analysis, illustrated by case studies of three tropical species from different aquatic environments: tilapia (Oreochromis aureus), red octopus (Octopus maya) and the Caribbean spiny lobster (Panulirus argus). The analysis undertaken compared the size distribution of males and females of a given cohort through modal progression analysis. The technique used proved to be useful for highlighting the differences in growth between females and males of a specific cohort. The potential effect of extrinsic and intrinsic factors on the organism's development as reflected in the size distribution of the cohorts is discussed.

  10. Octopus vulgaris (Cuvier, 1797) in the Mediterranean Sea: Genetic Diversity and Population Structure.

    PubMed

    De Luca, Daniele; Catanese, Gaetano; Procaccini, Gabriele; Fiorito, Graziano

    2016-01-01

    The common octopus, Octopus vulgaris Cuvier 1797, is a largely exploited cephalopod species in the Mediterranean Sea and the Atlantic Ocean, as well as along the coasts of Africa, Brazil and Japan, where its taxonomic identity is still debated. The assessment of its genetic structure is a pressing need to correctly manage the resource and to avoid overfishing and collapsing of local stocks. Here we analysed genetic variation and population structure of O. vulgaris using thirteen microsatellite loci in seven sampling localities from the Mediterranean Sea and one from the Atlantic Ocean. We also used a DNA barcoding approach by COI gene fragment to understand the phylogenetic relationships among the specimens here investigated and the ones whose sequences are available in literature. Our results reveal high levels of allelic richness and moderate heterozygosity in all samples investigated, and a pronounced differentiation of the Atlantic and Sicilian specimens. This latter aspect seems to support the isolation of the biota within the Strait of Messina. A certain degree of differentiation was detected among the other geographic samples within the Mediterranean Sea, which is more compatible with an island model than isolation by distance. The occurrence of null alleles affected more genetic diversity indices than population structure estimations. This study provides new insights about the genetic diversity and structure of O. vulgaris in the area of interest, which can be used as guidelines for a fisheries management perspective.

  11. Formation of a fluorous/organic biphasic supramolecular octopus assembly for enhanced porphyrin phosphorescence in air.

    PubMed

    Yang, Chi; Arvapally, Ravi K; Tekarli, Sammer M; Salazar, Gustavo A; Elbjeirami, Oussama; Wang, Xiaoping; Omary, Mohammad A

    2015-04-13

    The trinuclear triangle-shaped system [tris{3,5-bis(heptafluoropropyl)-1,2,4-triazolatosilver(I)}] (1) and the multi-armed square-shaped metalloporphyrin PtOEP or the free porphyrin base H2OEP serve as excellent octopus hosts (OEP=2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphine). Coupling of the fluorous/organic molecular octopi 1 and H2OEP or PtOEP by strong quadrupole-quadrupole and metal-π interactions affords the supramolecular assemblies [1⋅PtOEP] or [1⋅H2OEP] (2 a), which feature nanoscopic cavities surrounding the upper triangular and lower square cores. The fluorous/organic biphasic configuration of [1⋅PtOEP] leads to an increase in the phosphorescence of PtOEP under ambient conditions. Guest molecules can be included in the biphasic double-octopus assembly in three different site-selective modes.

  12. Sex identification and mating in the blue-ringed octopus, Hapalochlaena lunulata.

    PubMed

    Cheng; Caldwell

    2000-07-01

    We studied the reproductive behaviour of the blue-ringed octopus, Hapalochlaena lunulata, in the laboratory by examining 15 male-male and nine male-female interactions. The initiation of physical contact was independent of sex, size or residency status, and there were no noticeable changes in behaviour such as sexual displays associated with courtship or aggression prior to contact. Males did not distinguish between females or other males and copulated (defined as the insertion of the hectocotylus into the mantle cavity of another octopus) readily with both. Spermatophores were released in all copulations with females but not with males. The duration of copulation was significantly longer in male-female interactions (median 160.5 min) than in male-male interactions (median 30 s). Although male-male copulations ended passively with the withdrawal of the hectocotylus by the initiating animal, male-female copulations were always terminated by the females following an intense struggle. These studies suggest the inability of male H. lunulata to determine the sexual identity of potential mates prior to the insertion of the hectocotylus and demonstrate the active role of the female during copulation. Copyright 2000 The Association for the Study of Animal Behaviour. PMID:10924200

  13. How does the blue-ringed octopus (Hapalochlaena lunulata) flash its blue rings?

    PubMed

    Mäthger, Lydia M; Bell, George R R; Kuzirian, Alan M; Allen, Justine J; Hanlon, Roger T

    2012-11-01

    The blue-ringed octopus (Hapalochlaena lunulata), one of the world's most venomous animals, has long captivated and endangered a large audience: children playing at the beach, divers turning over rocks, and biologists researching neurotoxins. These small animals spend much of their time in hiding, showing effective camouflage patterns. When disturbed, the octopus will flash around 60 iridescent blue rings and, when strongly harassed, bite and deliver a neurotoxin that can kill a human. Here, we describe the flashing mechanism and optical properties of these rings. The rings contain physiologically inert multilayer reflectors, arranged to reflect blue-green light in a broad viewing direction. Dark pigmented chromatophores are found beneath and around each ring to enhance contrast. No chromatophores are above the ring; this is unusual for cephalopods, which typically use chromatophores to cover or spectrally modify iridescence. The fast flashes are achieved using muscles under direct neural control. The ring is hidden by contraction of muscles above the iridophores; relaxation of these muscles and contraction of muscles outside the ring expose the iridescence. This mechanism of producing iridescent signals has not previously been reported in cephalopods and we suggest that it is an exceptionally effective way to create a fast and conspicuous warning display. PMID:23053367

  14. Inter-cohort growth for three tropical resources: tilapia, octopus and lobster.

    PubMed

    Velázquez-Abunader, Iván; Gómez-Muñoz, Victor Manuel; Salas, Silvia; Ruiz-Velazco, Javier M J

    2015-09-01

    Growth parameters are an important component for the stock assessment of exploited aquatic species. However, it is often difficult to apply direct methods to estimate growth and to analyse the differences between males and females, particularly in tropical areas. The objective of this study was to analyse the inter-cohort growth of three tropical resources and discuss the possible fisheries management implications. A simple method was used to compare individual growth curves obtained from length frequency distribution analysis, illustrated by case studies of three tropical species from different aquatic environments: tilapia (Oreochromis aureus), red octopus (Octopus maya) and the Caribbean spiny lobster (Panulirus argus). The analysis undertaken compared the size distribution of males and females of a given cohort through modal progression analysis. The technique used proved to be useful for highlighting the differences in growth between females and males of a specific cohort. The potential effect of extrinsic and intrinsic factors on the organism's development as reflected in the size distribution of the cohorts is discussed. PMID:26666119

  15. Wind-driven upwelling effects on cephalopod paralarvae: Octopus vulgaris and Loliginidae off the Galician coast (NE Atlantic)

    NASA Astrophysics Data System (ADS)

    Otero, Jaime; Álvarez-Salgado, X. Antón; González, Ángel F.; Souto, Carlos; Gilcoto, Miguel; Guerra, Ángel

    2016-02-01

    Circulation patterns of coastal upwelling areas may have central consequences for the abundance and cross-shelf transport of the larval stages of many species. Previous studies have provided evidences that larvae distribution results from a combination of subtidal circulation, species-specific behaviour and larval sources. However, most of these works were conducted on organisms characterised by small-sized and abundant early life phases. Here, we studied the influence of the hydrography and circulation of the Ría de Vigo and adjacent shelf (NW Iberian upwelling system) on the paralarval abundance of two contrasting cephalopods, the benthic common octopus (Octopus vulgaris) and the pelagic squids (Loliginidae). We sampled repeatedly a cross-shore transect during the years 2003-2005 and used zero inflated models to accommodate the scarcity and patchy distribution of cephalopod paralarvae. The probability of catching early stages of both cephalopods was higher at night. Octopus paralarvae were more abundant in the surface layer at night whereas loliginids preferred the bottom layer regardless of the sampling time. Abundance of both cephalopods increased when shelf currents flowed polewards, water temperature was high and water column stability was low. The probability of observing an excess of zero catches decreased during the year for octopus and at high current speed for loliginids. In addition, the circulation pattern conditioned the body size distribution of both paralarvae; while the average size of the captured octopuses increased (decreased) with poleward currents at daylight (nighttime), squids were smaller with poleward currents regardless of the sampling time. These results contribute to the understanding of the effects that the hydrography and subtidal circulation of a coastal upwelling have on the fate of cephalopod early life stages.

  16. Immunohistochemical localization of two types of choline acetyltransferase in neurons and sensory cells of the octopus arm.

    PubMed

    Sakaue, Yuko; Bellier, Jean-Pierre; Kimura, Shin; D'Este, Loredana; Takeuchi, Yoshihiro; Kimura, Hiroshi

    2014-01-01

    Cholinergic structures in the arm of the cephalopod Octopus vulgaris were studied by immunohistochemistry using specific antisera for two types (common and peripheral) of acetylcholine synthetic enzyme choline acetyltransferase (ChAT): antiserum raised against the rat common type ChAT (cChAT), which is cross-reactive with molluscan cChAT, and antiserum raised against the rat peripheral type ChAT (pChAT), which has been used to delineate peripheral cholinergic structures in vertebrates, but not previously in invertebrates. Western blot analysis of octopus extracts revealed a single pChAT-positive band, suggesting that pChAT antiserum is cross-reactive with an octopus counterpart of rat pChAT. In immunohistochemistry, only neuronal structures of the octopus arm were stained by cChAT and pChAT antisera, although the pattern of distribution clearly differed between the two antisera. cChAT-positive varicose nerve fibers were observed in both the cerebrobrachial tract and neuropil of the axial nerve cord, while pChAT-positive varicose fibers were detected only in the neuropil of the axial nerve cord. After epitope retrieval, pChAT-positive neuronal cells and their processes became visible in all ganglia of the arm, including the axial and intramuscular nerve cords, and in ganglia of suckers. Moreover, pChAT-positive structures also became detectable in nerve fibers connecting the different ganglia, in smooth nerve fibers among muscle layers and dermal connective tissues, and in sensory cells of the suckers. These results suggest that the octopus arm has two types of cholinergic nerves: cChAT-positive nerves from brain ganglia and pChAT-positive nerves that are intrinsic to the arm.

  17. Population dynamics and stock assessment for Octopus maya (Cephalopoda: Octopodidae) fishery in the Campeche Bank, Gulf of Mexico.

    PubMed

    Arreguín-Sánchez, F; Solís-Ramírez, M J; González de la Rosa, M E

    2000-01-01

    The octopus (Octopus maya) is one of the most important fish resources in the Mexican Gulf of Mexico with a mean annual yield of 9000 ton, and a reasonable number of jobs created; O. maya represents 80% of the total octopus catch, followed by Octopus vulgaris. There are two artisanal fleets based on Octopus maya and a middle-size fleet that covers both species. Catch-at-length structured data from the artisanal fleets, for the 1994 season (August 1st to December 15th) were used to analyze the O. maya population dynamics and stock and to estimate the current level of exploitation. Von Bertalanffy growth parameters were: L infinity = 252 mm, mantle length; K = 1.4 year-1; oscillation parameters C = 1.0, WP = 0.6; and tz = 0.842 years. A rough estimate of natural mortality was M = 2.2, total mortality from catch curve Z = 8.77, and exploitation rate F/Z = 0.75. This last value suggests an intensive exploitation, even when yield per recruit analysis indicates both fleets may increase the minimum legal size on about 10% to increase yields. The length-based VPA also shows that the stock is being exploited under its maximum acceptable biological limit. These apparently contradictory results are explained by biological and behavioral characteristics of this species. Because most females die after reproduction, a new gross estimation of natural mortality was computed as M = 3.3. The new estimate of exploitation rate was F/Z = 0.57. This new value coincides with results from the length-VPA and the Thompson and Bell methods, the former suggesting that a reduction of 20% in fishing mortality may provide larger yields. This fishery resource is fully exploited and current management measures must be revised to sustain and probably optimize yields. PMID:11354940

  18. De Novo Transcriptome Sequencing of the Octopus vulgaris Hemocytes Using Illumina RNA-Seq Technology: Response to the Infection by the Gastrointestinal Parasite Aggregata octopiana

    PubMed Central

    Castellanos-Martínez, Sheila; Arteta, David; Catarino, Susana; Gestal, Camino

    2014-01-01

    Background Octopus vulgaris is a highly valuable species of great commercial interest and excellent candidate for aquaculture diversification; however, the octopus’ well-being is impaired by pathogens, of which the gastrointestinal coccidian parasite Aggregata octopiana is one of the most important. The knowledge of the molecular mechanisms of the immune response in cephalopods, especially in octopus is scarce. The transcriptome of the hemocytes of O. vulgaris was de novo sequenced using the high-throughput paired-end Illumina technology to identify genes involved in immune defense and to understand the molecular basis of octopus tolerance/resistance to coccidiosis. Results A bi-directional mRNA library was constructed from hemocytes of two groups of octopus according to the infection by A. octopiana, sick octopus, suffering coccidiosis, and healthy octopus, and reads were de novo assembled together. The differential expression of transcripts was analysed using the general assembly as a reference for mapping the reads from each condition. After sequencing, a total of 75,571,280 high quality reads were obtained from the sick octopus group and 74,731,646 from the healthy group. The general transcriptome of the O. vulgaris hemocytes was assembled in 254,506 contigs. A total of 48,225 contigs were successfully identified, and 538 transcripts exhibited differential expression between groups of infection. The general transcriptome revealed genes involved in pathways like NF-kB, TLR and Complement. Differential expression of TLR-2, PGRP, C1q and PRDX genes due to infection was validated using RT-qPCR. In sick octopuses, only TLR-2 was up-regulated in hemocytes, but all of them were up-regulated in caecum and gills. Conclusion The transcriptome reported here de novo establishes the first molecular clues to understand how the octopus immune system works and interacts with a highly pathogenic coccidian. The data provided here will contribute to identification of biomarkers

  19. RNA editing underlies temperature adaptation in K+ channels from polar octopuses.

    PubMed

    Garrett, Sandra; Rosenthal, Joshua J C

    2012-02-17

    To operate in the extreme cold, ion channels from psychrophiles must have evolved structural changes to compensate for their thermal environment. A reasonable assumption would be that the underlying adaptations lie within the encoding genes. Here, we show that delayed rectifier K(+) channel genes from an Antarctic and a tropical octopus encode channels that differ at only four positions and display very similar behavior when expressed in Xenopus oocytes. However, the transcribed messenger RNAs are extensively edited, creating functional diversity. One editing site, which recodes an isoleucine to a valine in the channel's pore, greatly accelerates gating kinetics by destabilizing the open state. This site is extensively edited in both Antarctic and Arctic species, but mostly unedited in tropical species. Thus adenosine-to-inosine RNA editing can respond to the physical environment.

  20. A review of simultaneous visual discrimination as a method of training octopuses.

    PubMed

    Boal, J G

    1996-05-01

    I have presented a review and critique of the procedures employed in simultaneous discrimination training experiments using octopuses as subjects. Procedural variables were analyzed statistically for their influence on experimental outcome. The variables most significantly associated with successful discriminations included use of a specific start location for subjects, shock as negative reinforcement, fewer trials per session, more sessions per day, and discriminations based on stimulus brightness. No experiment controlled all potential sources of inadvertent cues, and subjects' performances appeared to be sensitive to exact procedural details. The most common practice diminishing evidence for learning involved reward that coincided with the subject's pre-existing preferences. I found no evidence that sub-optimal experimental designs biased experimental outcomes in any significant and systematic way. Although there is sufficient reason for rejecting results of published simultaneous discrimination training experiments, careful conclusive experiments remain to be performed.

  1. Identical linkage and cooperativity of oxygen and carbon monoxide binding to Octopus dofleini hemocyanin.

    PubMed

    Connelly, P R; Gill, S J; Miller, K I; Zhou, G; van Holde, K E

    1989-02-21

    Employment of high-precision thin-layer methods has enabled detailed functional characterization of oxygen and carbon monoxide binding for (1) the fully assembled form with 70 binding sites and (2) the isolated chains with 7 binding sites of Octopus dofleini hemocyanin. The striking difference in the cooperativities of the two ligands for the assembled decamer is revealed through an examination of the binding capacities and the partition coefficient, determined as functions of the activities of both ligands. A global analysis of the data sets supported a two-state allosteric model assuming an allosteric unit of 7. Higher level allosteric interactions were not indicated. This contrasts to results obtained for arthropod hemocyanins. Oxygen and carbon monoxide experiments performed on the isolated subunit chain confirmed the presence of functional heterogeneity reported previously [Miller, K. (1985) Biochemistry 24, 4582-4586]. The analysis shows two types of binding sites in the ratio of 4:3. PMID:2719937

  2. Crystals of the carboxyl-terminal functional unit from Octopus dofleini hemocyanin.

    PubMed

    Cuff, M E; Hendrickson, W A; Lamy, J; Lamy, J N; Miller, K I; van Holde, K E

    1990-05-01

    The carboxyl-terminal oxygen-binding unit of the polypeptide from Octopus dofleini hemocyanin has been crystallized in a form suitable for three-dimensional X-ray analysis. This proteolytic fragment has a molecular weight of 47 kDa and reversibly binds O2 while exhibiting a slight Bohr effect. Two types of crystals have been grown. Type I crystals, currently under analysis, belong to the orthorhombic space group P2(1)2(1)2(1) and have unit cell dimensions of 92.6 A x 167.4 A x 59.2 A. A composition of two protein molecules per asymmetric unit and 50% solvent content is consistent with a self-rotation function that identifies a non-crystallographic 2-fold axis of symmetry relating these molecules. Diffraction extending beyond 1.9 A Bragg spacings can be detected with synchrotron X-radiation. PMID:2338711

  3. Neuroendocrine–Immune Systems Response to Environmental Stressors in the Cephalopod Octopus vulgaris

    PubMed Central

    Di Cosmo, Anna; Polese, Gianluca

    2016-01-01

    Under a continuous changing environment, animals are challenged with stresses and stimuli which demanding adaptation at behavioral and physiological levels. The adaptation strategies are finely regulated by animal nervous, endocrine, and immune systems. Although it's been established by now the usage of integrative approach to the study the endocrine and nervous systems (neuroendocrine), yet our understanding of how they cooperate with the immune system remains far from complete. The possible role that immune system plays as a component of the network has only been recognized recently. Octopus vulgaris is an important member of cephalopods and is considered as a model species, with considerable information about the neuroendocrine and immune systems. In the current review, we anticipate to shed light on the complexity and cross talk among the three systems and how they cooperate in setting physiological response to stresses-stimuli in O. vulgaris as a target species and primary example. PMID:27733834

  4. Biometrical relationships in developing eggs and neonates of Octopus vulgaris in relation to parental diet

    NASA Astrophysics Data System (ADS)

    Márquez, Lorenzo; Quintana, Daniel; Lorenzo, Antonio; Almansa, Eduardo

    2013-09-01

    Captive Octopus vulgaris adults were fed three mono-diets based on pilchard, crab and squid and allowed to grow until reproduction under controlled temperature. Spawns from each dietary treatment were isolated, and the embryonic development, egg length, width and wet weight, in addition to neonate dry weight, dorsal mantle length and ventral mantle length were monitored. Pilchard-diet spawns developed faster in terms of thermal time. Initial egg wet weight was higher for squid and crab diets. Irrespective of the parental diet, eggs passed through a swelling process so that egg width and wet weight increased in a nonlinear way, whereas egg length was left nearly unaffected. Egg length and initial wet weight showed a high correlation with neonate dry weight. Egg length, even at advanced incubation, can be used as a good proxy for neonate dry weight, this fact having potential implications for the ecological and aquaculture research on O. vulgaris.

  5. Identical linkage and cooperativity of oxygen and carbon monoxide binding to Octopus dofleini hemocyanin

    SciTech Connect

    Connelly, P.R.; Gill, S.J.; Miller, K.I.; Zhou, G.; van Holde, K.E. )

    1989-02-21

    Employment of high-precision thin-layer methods has enabled detailed functional characterization of oxygen and carbon monoxide binding for (1) the fully assembled form with 70 binding sites and (2) the isolated chains with 7 binding sites of octopus dofleini hemocyanin. The striking difference in the cooperativities of the two ligands for the assembled decamer is revealed through an examination of the binding capacities and the partition coefficient, determined as functions of the activities of both ligands. A global analysis of the data sets supported by a two-state allosteric model assuming an allosteric unit of 7. Higher level allosteric interactions were not indicated. This contrasts to results obtained for arthropod hemocyanins. Oxygen and carbon monoxide experiments performed on the isolated subunit chain confirmed the presence of functional heterogeneity reported previously. The analysis shows two types of binding sites in the ratio of 4:3.

  6. Behavioural and immunological responses to an immune challenge in Octopus vulgaris.

    PubMed

    Locatello, Lisa; Fiorito, Graziano; Finos, Livio; Rasotto, Maria B

    2013-10-01

    Behavioural and immunological changes consequent to stress and infection are largely unexplored in cephalopods, despite the wide employment of species such as Octopus vulgaris in studies that require their manipulation and prolonged maintenance in captivity. Here we explore O. vulgaris behavioural and immunological (i.e. haemocyte number and serum lysozyme activity) responses to an in vivo immune challenge with Escherichia coli lipopolysaccharides (LPS). Behavioural changes of immune-treated and sham-injected animals were observed in both sight-allowed and isolated conditions, i.e. visually interacting or not with a conspecific. Immune stimulation primarily caused a significant increase in the number of circulating haemocytes 4h after the treatment, while serum lysozyme activity showed a less clear response. However, the effect of LPS on the circulating haemocytes begins to vanish 24h after injection. Our observations indicate a significant change in behaviour consequent to LPS administration, with treated octopuses exhibiting a decrease of general activity pattern when kept in the isolated condition. A similar decrease was not observed in the sight-allowed condition, where we noticed a specific significant reduction only in the time spent to visually interact with the conspecific. Overall, significant, but lower, behavioural and immunological effects of injection were detected also in sham-injected animals, suggesting a non-trivial susceptibility to manipulation and haemolymph sampling. Our results gain importance in light of changes of the regulations for the use of cephalopods in scientific procedures that call for the prompt development of guidelines, covering many aspects of cephalopod provision, maintenance and welfare.

  7. Comparison of Reconstruction and Control algorithms on the ESO end-to-end simulator OCTOPUS

    NASA Astrophysics Data System (ADS)

    Montilla, I.; Béchet, C.; Lelouarn, M.; Correia, C.; Tallon, M.; Reyes, M.; Thiébaut, É.

    Extremely Large Telescopes are very challenging concerning their Adaptive Optics requirements. Their diameters, the specifications demanded by the science for which they are being designed for, and the planned use of Extreme Adaptive Optics systems, imply a huge increment in the number of degrees of freedom in the deformable mirrors. It is necessary to study new reconstruction algorithms to implement the real time control in Adaptive Optics at the required speed. We have studied the performance, applied to the case of the European ELT, of three different algorithms: the matrix-vector multiplication (MVM) algorithm, considered as a reference; the Fractal Iterative Method (FrIM); and the Fourier Transform Reconstructor (FTR). The algorithms have been tested on ESO's OCTOPUS software, which simulates the atmosphere, the deformable mirror, the sensor and the closed-loop control. The MVM is the default reconstruction and control method implemented in OCTOPUS, but it scales in O(N2) operations per loop so it is not considered as a fast algorithm for wave-front reconstruction and control on an Extremely Large Telescope. The two other methods are the fast algorithms studied in the E-ELT Design Study. The performance, as well as their response in the presence of noise and with various atmospheric conditions, has been compared using a Single Conjugate Adaptive Optics configuration for a 42 m diameter ELT, with a total amount of 5402 actuators. Those comparisons made on a common simulator allow to enhance the pros and cons of the various methods, and give us a better understanding of the type of reconstruction algorithm that an ELT demands.

  8. Thermopreference, tolerance and metabolic rate of early stages juvenile Octopus maya acclimated to different temperatures.

    PubMed

    Noyola, Javier; Caamal-Monsreal, Claudia; Díaz, Fernando; Re, Denisse; Sánchez, Adolfo; Rosas, Carlos

    2013-01-01

    Thermopreference, tolerance and oxygen consumption rates of early juveniles Octopus maya (O. maya; weight range 0.38-0.78g) were determined after acclimating the octopuses to temperatures (18, 22, 26, and 30°C) for 20 days. The results indicated a direct relationship between preferred temperature (PT) and acclimated temperature, the PT was 23.4°C. Critical Thermal Maxima, (CTMax; 31.8±1.2, 32.7±0.9, 34.8±1.4 and 36.5±1.0) and Critical Thermal Minima, (CTMin; 11.6±0.2, 12.8±0.6, 13.7±1.0, 19.00±0.9) increased significantly (P<0.05) with increasing acclimation temperatures. The endpoint for CTMax was ink release and for CTMin was tentacles curled, respectively. A thermal tolerance polygon over the range of 18-30°C resulted in a calculated area of 210.0°C(2). The oxygen consumption rate increased significantly α=0.05 with increasing acclimation temperatures between 18 and 30°C. Maximum and minimum temperature quotients (Q10) were observed between 26-30°C and 22-26°C as 3.03 and 1.71, respectively. These results suggest that O. maya has an increased capability for adapting to moderate temperatures, and suggest increased culture potential in subtropical regions southeast of México.

  9. Thermopreference, tolerance and metabolic rate of early stages juvenile Octopus maya acclimated to different temperatures.

    PubMed

    Noyola, Javier; Caamal-Monsreal, Claudia; Díaz, Fernando; Re, Denisse; Sánchez, Adolfo; Rosas, Carlos

    2013-01-01

    Thermopreference, tolerance and oxygen consumption rates of early juveniles Octopus maya (O. maya; weight range 0.38-0.78g) were determined after acclimating the octopuses to temperatures (18, 22, 26, and 30°C) for 20 days. The results indicated a direct relationship between preferred temperature (PT) and acclimated temperature, the PT was 23.4°C. Critical Thermal Maxima, (CTMax; 31.8±1.2, 32.7±0.9, 34.8±1.4 and 36.5±1.0) and Critical Thermal Minima, (CTMin; 11.6±0.2, 12.8±0.6, 13.7±1.0, 19.00±0.9) increased significantly (P<0.05) with increasing acclimation temperatures. The endpoint for CTMax was ink release and for CTMin was tentacles curled, respectively. A thermal tolerance polygon over the range of 18-30°C resulted in a calculated area of 210.0°C(2). The oxygen consumption rate increased significantly α=0.05 with increasing acclimation temperatures between 18 and 30°C. Maximum and minimum temperature quotients (Q10) were observed between 26-30°C and 22-26°C as 3.03 and 1.71, respectively. These results suggest that O. maya has an increased capability for adapting to moderate temperatures, and suggest increased culture potential in subtropical regions southeast of México. PMID:24229799

  10. Lactogenic Activity of an Enzymatic Hydrolysate from Octopus vulgaris and Carica papaya in SD Rats.

    PubMed

    Cai, Bingna; Chen, Hua; Sun, Han; Sun, Huili; Wan, Peng; Chen, Deke; Pan, Jianyu

    2015-11-01

    The traditional Chinese medicine theory believes that octopus papaya soup can stimulate milk production in lactating women. The objective of this study was to determine whether dietary supplementation with an enzymatic hydrolysate of Octopus vulgaris and Carica papaya (EHOC) could increase milk production and nutritional indexes in Sprague Dawley (SD) rats. Female SD rats (n = 24) were fed a control diet (n = 8), EHOC-supplemented diet, or a positive control diet (Shengruzhi) from day 10 of pregnancy to day 10 of lactation. Maternal serum, mammary gland (day 10 of lactation), milk, and pup weight (daily) were collected for analysis. Results showed that the EHOC diet obviously elevated daily milk yield and pup weight compared to the control group (P < .05). The EHOC diet was found to increase the concentration of prolactin (PRL), progesterone (P), estradiol (E2), and growth hormone (GH) significantly in the circulation and mammary gland. Mammary glands of EHOC-treated dams showed clear lobuloalveolar development and proliferation of myoepithelial cells, but no striking variations were observed among the groups. Furthermore, the nutrition content and immune globulin concentration in the milk of EHOC-supplemented dams were higher than those of the control group, especially the cholesterol, glucose, and IgG were higher by 44.98% (P < .001), 42.76% (P < .01), and 42.23% (P < .01), respectively. In conclusion, this article demonstrates that EHOC administration has beneficial effects on milk production in the dams and on performance of the dam and pup. These results indicate that EHOC could be explored as a potentially lactogenic nutriment for lactating women. PMID:26270883

  11. Lactogenic Activity of an Enzymatic Hydrolysate from Octopus vulgaris and Carica papaya in SD Rats.

    PubMed

    Cai, Bingna; Chen, Hua; Sun, Han; Sun, Huili; Wan, Peng; Chen, Deke; Pan, Jianyu

    2015-11-01

    The traditional Chinese medicine theory believes that octopus papaya soup can stimulate milk production in lactating women. The objective of this study was to determine whether dietary supplementation with an enzymatic hydrolysate of Octopus vulgaris and Carica papaya (EHOC) could increase milk production and nutritional indexes in Sprague Dawley (SD) rats. Female SD rats (n = 24) were fed a control diet (n = 8), EHOC-supplemented diet, or a positive control diet (Shengruzhi) from day 10 of pregnancy to day 10 of lactation. Maternal serum, mammary gland (day 10 of lactation), milk, and pup weight (daily) were collected for analysis. Results showed that the EHOC diet obviously elevated daily milk yield and pup weight compared to the control group (P < .05). The EHOC diet was found to increase the concentration of prolactin (PRL), progesterone (P), estradiol (E2), and growth hormone (GH) significantly in the circulation and mammary gland. Mammary glands of EHOC-treated dams showed clear lobuloalveolar development and proliferation of myoepithelial cells, but no striking variations were observed among the groups. Furthermore, the nutrition content and immune globulin concentration in the milk of EHOC-supplemented dams were higher than those of the control group, especially the cholesterol, glucose, and IgG were higher by 44.98% (P < .001), 42.76% (P < .01), and 42.23% (P < .01), respectively. In conclusion, this article demonstrates that EHOC administration has beneficial effects on milk production in the dams and on performance of the dam and pup. These results indicate that EHOC could be explored as a potentially lactogenic nutriment for lactating women.

  12. Model based optimization of feeding regimens in aquaculture: application to the improvement of Octopus vulgaris viability in captivity.

    PubMed

    Hormiga, José A; Almansa, Eduardo; Sykes, António V; Torres, Néstor V

    2010-09-01

    The culture of common octopus (Octopus vulgaris), one important candidate to the aquaculture diversification, faces significant difficulties, mainly related with an inadequate first development stages diet. A mathematical model integrating disperse information on the nutrient composition throughout the species ontogenic development as well as on the effects of broodstock feeding and diet composition data of O. vulgaris, allowed us to predict the time evolution of paralarvae nutritional composition in terms of protein and lipid fractions and to design an optimal diet composition with the objective to ensure the maximal survival. The optimization routine showed that a diet based on the spider crab (Maja squinado) zoea composition is the most suitable for reaching the best survival rates. Results are verified by comparison with available experimental data. The obtained results and the prospective developments are a good example of how the systemic, quantitative model based approach can be used to analyse and contribute to the understanding of complex biological systems. PMID:20005909

  13. Determination of the average orientation of DNA in the octopus sperm [ital Eledone] [ital cirrhossa] through polarized light scattering

    SciTech Connect

    Shapiro, D.B.; Maestre, M.F.; McClain, W.M.; Hull, P.G.; Shi, Y.; Quinby-Hunt, M.S.; Hearst, J.E.; Hunt, A.J. )

    1994-08-20

    The coupled-dipole approximation has been used to model polarized light-scattering data obtained from the sperm of the octopus [ital Eledone] [ital cirrhosa]. Mueller scattering-matrix elements (which describe how a sample alters the intensity and degree of polarization of scattered light) were measured as a function of angle. The sample was modeled as a helical fiber believed to correspond to a DNA protein complex. It was necessary to propose an inherent anisotropy in the polarizability of the fiber in order to fit the data. The direction of the principle axes of the polarizability were determined by comparing the model with experimental data. The results suggest that the 2-nm DNA fibers are perpendicular to the thick fiber that defines the helical geometry of the octopus sperm head.

  14. A numerical investigation of flow around octopus-like arms: near-wake vortex patterns and force development.

    PubMed

    Kazakidi, A; Vavourakis, V; Tsakiris, D P; Ekaterinaris, J A

    2015-01-01

    The fluid dynamics of cephalopods has so far received little attention in the literature, due to their complexity in structure and locomotion. The flow around octopuses, in particular, can be complicated due to their agile and dexterous arms, which frequently display some of the most diverse mechanisms of motion. The study of this flow amounts to a specific instance of the hydrodynamics problem for rough tapered cylinder geometries. The outstanding manipulative and locomotor skills of octopuses could inspire the development of advanced robotic arms, able to operate in fluid environments. Our primary aim was to study the hydrodynamic characteristics of such bio-inspired robotic models and to derive the hydrodynamic force coefficients as a concise description of the vortical flow effects. Utilizing computational fluid dynamic methods, the coefficients were computed on realistic morphologies of octopus-like arm models undergoing prescribed solid-body movements; such motions occur in nature for short durations in time, e.g. during reaching movements and exploratory behaviors. Numerical simulations were performed on translating, impulsively rotating, and maneuvering arms, around which the flow field structures were investigated. The results reveal in detail the generation of complex vortical flow structures around the moving arms. Hydrodynamic forces acting on a translating arm depend on the angle of incidence; forces generated during impulsive rotations of the arms are independent of their exact morphology and the angle of rotation; periodic motions based on a slow recovery and a fast power stroke are able to produce considerable propulsive thrust while harmonic motions are not. Parts of these results have been employed in bio-inspired models of underwater robotic mechanisms. This investigation may further assist elucidating the hydrodynamics underlying aspects of octopus locomotion and exploratory behaviors.

  15. A numerical investigation of flow around octopus-like arms: near-wake vortex patterns and force development.

    PubMed

    Kazakidi, A; Vavourakis, V; Tsakiris, D P; Ekaterinaris, J A

    2015-01-01

    The fluid dynamics of cephalopods has so far received little attention in the literature, due to their complexity in structure and locomotion. The flow around octopuses, in particular, can be complicated due to their agile and dexterous arms, which frequently display some of the most diverse mechanisms of motion. The study of this flow amounts to a specific instance of the hydrodynamics problem for rough tapered cylinder geometries. The outstanding manipulative and locomotor skills of octopuses could inspire the development of advanced robotic arms, able to operate in fluid environments. Our primary aim was to study the hydrodynamic characteristics of such bio-inspired robotic models and to derive the hydrodynamic force coefficients as a concise description of the vortical flow effects. Utilizing computational fluid dynamic methods, the coefficients were computed on realistic morphologies of octopus-like arm models undergoing prescribed solid-body movements; such motions occur in nature for short durations in time, e.g. during reaching movements and exploratory behaviors. Numerical simulations were performed on translating, impulsively rotating, and maneuvering arms, around which the flow field structures were investigated. The results reveal in detail the generation of complex vortical flow structures around the moving arms. Hydrodynamic forces acting on a translating arm depend on the angle of incidence; forces generated during impulsive rotations of the arms are independent of their exact morphology and the angle of rotation; periodic motions based on a slow recovery and a fast power stroke are able to produce considerable propulsive thrust while harmonic motions are not. Parts of these results have been employed in bio-inspired models of underwater robotic mechanisms. This investigation may further assist elucidating the hydrodynamics underlying aspects of octopus locomotion and exploratory behaviors. PMID:24730546

  16. Respiratory failure and lethal hypotension due to blue-ringed octopus and tetrodotoxin envenomation observed and counteracted in animal models.

    PubMed

    Flachsenberger, W A

    The effects of crude blue-ringed octopus venom gland extract and tetrodotoxin (TTX) on anaesthetised rats and rabbits were studied. Paralysis of the respiratory musculature causing anoxia and cyanosis was overcome with positive, artificial respiration. The second lethal mechanism of the toxins: rapid and severe hypotension, had to be counteracted peripherally, since neural transmission had been drastically reduced by the toxins. Noradrenaline, d-amphetamine, phenylephrine and methoxamine, agonists acting on vascular adrenergic a-receptors, were tested. PMID:3573123

  17. Identification of a Δ5-like fatty acyl desaturase from the cephalopod Octopus vulgaris (Cuvier 1797) involved in the biosynthesis of essential fatty acids.

    PubMed

    Monroig, Oscar; Navarro, Juan C; Dick, James R; Alemany, Frederic; Tocher, Douglas R

    2012-08-01

    Long-chain polyunsaturated fatty acids (LC-PUFA) have been identified as essential compounds for common octopus (Octopus vulgaris), but precise dietary requirements have not been determined due, in part, to the inherent difficulties of performing feeding trials on paralarvae. Our objective is to establish the essential fatty acid (EFA) requirements for paralarval stages of the common octopus through characterisation of the enzymes of endogenous LC-PUFA biosynthetic pathways. In this study, we isolated a cDNA with high homology to fatty acyl desaturases (Fad). Functional characterisation in recombinant yeast showed that the octopus Fad exhibited Δ5-desaturation activity towards saturated and polyunsaturated fatty acyl substrates. Thus, it efficiently converted the yeast's endogenous 16:0 and 18:0 to 16:1n-11 and 18:1n-13, respectively, and desaturated exogenously added PUFA substrates 20:4n-3 and 20:3n-6 to 20:5n-3 (EPA) and 20:4n-6 (ARA), respectively. Although the Δ5 Fad enables common octopus to produce EPA and ARA, the low availability of its adequate substrates 20:4n-3 and 20:3n-6, either in the diet or by limited endogenous synthesis from C(18) PUFA, might indicate that EPA and ARA are indeed EFA for this species. Interestingly, the octopus Δ5 Fad can also participate in the biosynthesis of non-methylene-interrupted FA, PUFA that are generally uncommon in vertebrates but have been found previously in marine invertebrates, including molluscs, and now also confirmed to be present in specific tissues of common octopus.

  18. Selection of reliable reference genes for RT-qPCR studies in Octopus vulgaris paralarvae during development and immune-stimulation.

    PubMed

    García-Fernández, P; Castellanos-Martínez, S; Iglesias, J; Otero, J J; Gestal, C

    2016-07-01

    The common octopus, Octopus vulgaris is a new candidate species for aquaculture. However, rearing of octopus paralarvae is hampered by high mortality and poor growth rates that impede its entire culture. The study of genes involved in the octopus development and immune response capability could help to understand the key of paralarvae survival and thus, to complete the octopus life cycle. Quantitative real-time PCR (RT-qPCR) is the most frequently tool used to quantify the gene expression because of specificity and sensitivity. However, reliability of RT-qPCR requires the selection of appropriate normalization genes whose expression must be stable across the different experimental conditions of the study. Hence, the aim of the present work is to evaluate the stability of six candidate genes: β-actin (ACT), elongation factor 1-α (EF), ubiquitin (UBI), β-tubulin (TUB), glyceraldehyde 3-phosphate dehydrogenase (GADPH) and ribosomal RNA 18 (18S) in order to select the best reference gene. The stability of gene expression was analyzed using geNorm, NormFinder and Bestkeeper, in octopus paralarvae of seven developmental stages (embryo, paralarvae of 0, 10, 15, 20, 30 and 34days) and paralarvae of 20days after challenge with Vibrio lentus and Vibrio splendidus. The results were validated by measuring the expression of PGRP, a stimuli-specific gene. Our results showed UBI, EF and 18S as the most suitable reference genes during development of octopus paralarvae, and UBI, ACT and 18S for bacterial infection. These results provide a basis for further studies exploring molecular mechanism of their development and innate immune defense. PMID:27267177

  19. Deep-sea octopus (Graneledone boreopacifica) conducts the longest-known egg-brooding period of any animal.

    PubMed

    Robison, Bruce; Seibel, Brad; Drazen, Jeffrey

    2014-01-01

    Octopuses typically have a single reproductive period and then they die (semelparity). Once a clutch of fertilized eggs has been produced, the female protects and tends them until they hatch. In most shallow-water species this period of parental care can last from 1 to 3 months, but very little is known about the brooding of deep-living species. In the cold, dark waters of the deep ocean, metabolic processes are often slower than their counterparts at shallower depths. Extrapolations from data on shallow-water octopus species suggest that lower temperatures would prolong embryonic development periods. Likewise, laboratory studies have linked lower temperatures to longer brooding periods in cephalopods, but direct evidence has not been available. We found an opportunity to directly measure the brooding period of the deep-sea octopus Graneledone boreopacifica, in its natural habitat. At 53 months, it is by far the longest egg-brooding period ever reported for any animal species. These surprising results emphasize the selective value of prolonged embryonic development in order to produce competitive hatchlings. They also extend the known boundaries of physiological adaptations for life in the deep sea.

  20. Deep-sea octopus (Graneledone boreopacifica) conducts the longest-known egg-brooding period of any animal.

    PubMed

    Robison, Bruce; Seibel, Brad; Drazen, Jeffrey

    2014-01-01

    Octopuses typically have a single reproductive period and then they die (semelparity). Once a clutch of fertilized eggs has been produced, the female protects and tends them until they hatch. In most shallow-water species this period of parental care can last from 1 to 3 months, but very little is known about the brooding of deep-living species. In the cold, dark waters of the deep ocean, metabolic processes are often slower than their counterparts at shallower depths. Extrapolations from data on shallow-water octopus species suggest that lower temperatures would prolong embryonic development periods. Likewise, laboratory studies have linked lower temperatures to longer brooding periods in cephalopods, but direct evidence has not been available. We found an opportunity to directly measure the brooding period of the deep-sea octopus Graneledone boreopacifica, in its natural habitat. At 53 months, it is by far the longest egg-brooding period ever reported for any animal species. These surprising results emphasize the selective value of prolonged embryonic development in order to produce competitive hatchlings. They also extend the known boundaries of physiological adaptations for life in the deep sea. PMID:25075745

  1. Deep-Sea Octopus (Graneledone boreopacifica) Conducts the Longest-Known Egg-Brooding Period of Any Animal

    PubMed Central

    Robison, Bruce; Seibel, Brad; Drazen, Jeffrey

    2014-01-01

    Octopuses typically have a single reproductive period and then they die (semelparity). Once a clutch of fertilized eggs has been produced, the female protects and tends them until they hatch. In most shallow-water species this period of parental care can last from 1 to 3 months, but very little is known about the brooding of deep-living species. In the cold, dark waters of the deep ocean, metabolic processes are often slower than their counterparts at shallower depths. Extrapolations from data on shallow-water octopus species suggest that lower temperatures would prolong embryonic development periods. Likewise, laboratory studies have linked lower temperatures to longer brooding periods in cephalopods, but direct evidence has not been available. We found an opportunity to directly measure the brooding period of the deep-sea octopus Graneledone boreopacifica, in its natural habitat. At 53 months, it is by far the longest egg-brooding period ever reported for any animal species. These surprising results emphasize the selective value of prolonged embryonic development in order to produce competitive hatchlings. They also extend the known boundaries of physiological adaptations for life in the deep sea. PMID:25075745

  2. The octopus vertical lobe modulates short-term learning rate and uses LTP to acquire long-term memory.

    PubMed

    Shomrat, Tal; Zarrella, Ilaria; Fiorito, Graziano; Hochner, Binyamin

    2008-03-11

    Analyzing the processes and neuronal circuitry involved in complex behaviors in phylogenetically remote species can help us understand the evolution and function of these systems. Cephalopods, with their vertebrate-like behaviors but much simpler brains, are ideal for such an analysis. The vertical lobe (VL) of Octopus vulgaris is a pivotal brain station in its learning and memory system. To examine the organization of the learning and memory circuitry and to test whether the LTP that we discovered in the VL is involved in behavioral learning, we tetanized the VL to induce a global synaptic enhancement of the VL pathway. The effects of tetanization on learning and memory of a passive avoidance task were compared to those of transecting the same pathway. Tetanization accelerated and transection slowed short-term learning to avoid attacking a negatively reinforced object. However, both treatments impaired long-term recall the next day. Our results suggest that the learning and memory system in the octopus, as in mammals [9], is separated into short- and long-term memory sites. In the octopus, the two memory sites are not independent; the VL, which mediates long-term memory acquisition through LTP, also modulates the circuitry controlling behavior and short-term learning.

  3. Role of the tertiary structure in the diphenol oxidase activity of Octopus vulgaris hemocyanin.

    PubMed

    Campello, S; Beltramini, M; Giordano, G; Di Muro, P; Marino, S M; Bubacco, L

    2008-03-15

    The functional differences between the oxygen transport protein Hemocyanin and the enzymes Tyrosinase and Catechol oxidase are believed to be governed, at least in part, by the tertiary structure, which differs in these molecules and controls the accessibility of their copper containing active site for substrate(s). Accordingly, Octopus vulgaris Hemocyanin catalyses the o-diphenol oxidation to o-quinone at a very low rate. The crystallographic structure of one of the functional units (called Odg) of O. dofleini Hemocyanin shows two domains, a mainly alpha-helical domain that directly binds the copper ions of the reaction center and a beta-strand domain that precludes access to the active site to ligands bigger than molecular oxygen. In this work, we have first cleaved the whole protein and then purified different oxygen binding functional units from O. vulgaris Hemocyanin. These functional units were used in activity assays with l-DOPA, the paradigmatic substrate for Catechol oxidase. All functional units show a negligible enzymatic activity. The procedure to generate the functional units induces in only one of them a proteolytic cleavage. Amino terminal sequencing and mass spectroscopy of the fragments allow to place the cleavage site between the alpha and beta domains of the functional unit homologous to Odd, in the O. dofleini sequence. An increase, up to three orders of magnitude, of Tyrosinase-like activity was observed when the cleaved Odd-like was incubated with the substrate in the presence of trifluoroethanol or hexafluoroisopropanol. PMID:18237542

  4. Arrangement of subunits and domains within the Octopus dofleini hemocyanin molecule.

    PubMed Central

    Miller, K I; Schabtach, E; van Holde, K E

    1990-01-01

    Native Octopus dofleini hemocyanin appears as a hollow cylinder in the electron microscope. It is composed of 10 polypeptide subunits, each folded into seven globular oxygen-binding domains. The native structure reassociates spontaneously from subunits in the presence of Mg2+ ions. We have selectively removed the C-terminal domain and purified the resulting six-domain subunits. Although these six-domain subunits do not associate efficiently at pH 7.2, they undergo nearly complete reassociation at pH 8.0. The resulting molecule looks like the native cylindrical whole molecule but lacks the usual fivefold protrusions into the central cavity. Partially reassociated mixtures show dimers of the subunit that have a characteristic parallelogram shape when lying flat on the electron microscope grid, and a "boat" form in side view. Removal of the C-terminal domain from monomers results in the removal of two characteristically placed domains in the dimers. These observations allow the development of a model for the arrangement of the subunits within the whole molecule. The model predicts exactly the views seen in the electron microscope of both whole molecule and dimeric intermediates. Images PMID:2304914

  5. Arrangement of subunits and domains within the Octopus dofleini hemocyanin molecule.

    PubMed

    Miller, K I; Schabtach, E; van Holde, K E

    1990-02-01

    Native Octopus dofleini hemocyanin appears as a hollow cylinder in the electron microscope. It is composed of 10 polypeptide subunits, each folded into seven globular oxygen-binding domains. The native structure reassociates spontaneously from subunits in the presence of Mg2+ ions. We have selectively removed the C-terminal domain and purified the resulting six-domain subunits. Although these six-domain subunits do not associate efficiently at pH 7.2, they undergo nearly complete reassociation at pH 8.0. The resulting molecule looks like the native cylindrical whole molecule but lacks the usual fivefold protrusions into the central cavity. Partially reassociated mixtures show dimers of the subunit that have a characteristic parallelogram shape when lying flat on the electron microscope grid, and a "boat" form in side view. Removal of the C-terminal domain from monomers results in the removal of two characteristically placed domains in the dimers. These observations allow the development of a model for the arrangement of the subunits within the whole molecule. The model predicts exactly the views seen in the electron microscope of both whole molecule and dimeric intermediates. PMID:2304914

  6. cDNA cloning of the Octopus dofleini hemocyanin: sequence of the carboxyl-terminal domain.

    PubMed

    Lang, W H

    1988-09-20

    A cDNA library was constructed in pUC 19, using poly(A+) RNA purified from Octopus dofleini branchial gland, which is the site of hemocyanin biosynthesis in cephalopods. The library was screened with an oligonucleotide probe derived from a portion of the partially known sequence of the C-terminal domain of Paroctopus dofleini dofleini. The clone with the longest insert--called pHC1--was sequenced and used as a probe for Northern blotting. It hybridized to a 9.5-kb RNA species, which was also visible as a band after ethidium bromide staining. The cDNA insert (approximately 1200 bp) of pHC1 contained an open reading frame of 1071 bp coding for 357 amino acids. In this insert, a region coding for 42 amino acids from the N-terminal end of the C-terminal domain is missing. These were obtained by sequencing a cloned primer extension product. By comparing our sequence with Helix pomatia beta c-hemocyanin unit D, we found 42.9% identical and 11.5% similar residues. One putative copper binding site (site B) was identified by homology to Helix hemocyanin and arthropodan hemocyanin. The location of a second possible site was identified. PMID:3207675

  7. An investigation of the nature of Bohr, Root, and Haldane effects in Octopus dofleini hemocyanin.

    PubMed

    Miller, K I; Mangum, C P

    1988-01-01

    1. The pH dependence of Octopus dofleini hemocyanin oxygenation is so great that below pH 7.0 the molecule does not become fully oxygenated, even in pure O2 at 1 atm pressure. However, the curves describing percent oxygenation as a function of PO2 appear to be gradually increasing in oxygen saturation, rather than leveling out at less than full saturation. Hill plots indicate that at pH 6.6 and below the molecule is stabilized in its low affinity conformation. Thus, the low saturation of this hemocyanin in air is due to the very large Bohr shift, and not to the disabling of one or more functionally distinct O2 binding sites on the native molecule. 2. Experiments in which pH was monitored continuously while oxygenation was manipulated in the presence of CO2 provide no evidence of O2 linked binding of CO2. While CO2 does influence O2 affinity independently of pH, its effect may be due to high levels of HCO3- and CO3-, rather than molecular CO2, and it may entail a lowering of the activities of the allosteric effectors Mg2+ and Ca2+. PMID:3150406

  8. Ultra-fast escape maneuver of an octopus-inspired robot.

    PubMed

    Weymouth, G D; Subramaniam, V; Triantafyllou, M S

    2015-01-01

    We design and test an octopus-inspired flexible hull robot that demonstrates outstanding fast-starting performance. The robot is hyper-inflated with water, and then rapidly deflates to expel the fluid so as to power the escape maneuver. Using this robot we verify for the first time in laboratory testing that rapid size-change can substantially reduce separation in bluff bodies traveling several body lengths, and recover fluid energy which can be employed to improve the propulsive performance. The robot is found to experience speeds over ten body lengths per second, exceeding that of a similarly propelled optimally streamlined rigid rocket. The peak net thrust force on the robot is more than 2.6 times that on an optimal rigid body performing the same maneuver, experimentally demonstrating large energy recovery and enabling acceleration greater than 14 body lengths per second squared. Finally, over 53% of the available energy is converted into payload kinetic energy, a performance that exceeds the estimated energy conversion efficiency of fast-starting fish. The Reynolds number based on final speed and robot length is [Formula: see text]. We use the experimental data to establish a fundamental deflation scaling parameter [Formula: see text] which characterizes the mechanisms of flow control via shape change. Based on this scaling parameter, we find that the fast-starting performance improves with increasing size. PMID:25643048

  9. Dynamics of underwater legged locomotion: modeling and experiments on an octopus-inspired robot.

    PubMed

    Calisti, M; Corucci, F; Arienti, A; Laschi, C

    2015-08-01

    This paper studies underwater legged locomotion (ULL) by means of a robotic octopus-inspired prototype and its associated model. Two different types of propulsive actions are embedded into the robot model: reaction forces due to leg contact with the ground and hydrodynamic forces such as the drag arising from the sculling motion of the legs. Dynamic parameters of the model are estimated by means of evolutionary techniques and subsequently the model is exploited to highlight some distinctive features of ULL. Specifically, the separation between the center of buoyancy (CoB)/center of mass and density affect the stability and speed of the robot, whereas the sculling movements contribute to propelling the robot even when its legs are detached from the ground. The relevance of these effects is demonstrated through robotic experiments and model simulations; moreover, by slightly changing the position of the CoB in the presence of the same feed-forward activation, a number of different behaviors (i.e. forward and backward locomotion at different speeds) are achieved. PMID:26226238

  10. On gonadic maturation and reproductive strategy in deep-sea benthic octopus Graneledone macrotyla

    NASA Astrophysics Data System (ADS)

    Guerra, Ángel; Sieiro, María Pilar; Roura, Álvaro; Portela, Julio M.; del Río, José Luís

    2013-09-01

    The new information reported in this paper is based on five maturing and mature females of the large-tuberculate octopus Graneledone macrotyla. These specimens were caught in bottom trawl surveys ATLANTIS 2009 (February 24 to April 1, 2009) and ATLANTIS 2010 (March 9 to April 5, 2010) carried out off the Argentinean Economic Exclusive Zone. Capture depth ranged from 475 to 921 m and sea bottom temperature between 2.8 and 3.1 °C. Development of the complex ovary, oviducts, and oviducal glands during gonadic maturation is described. The absence of spermathecae in the oviducal glands and the presence of fertilized eggs inside the ovary suggested that fertilization took place within the ovary. Histological techniques showed the presence of four types of oocytes. Maturing oocyte size-frequency distribution was polymodal. Fluorescence reaction showed that atresia occurred in both early and later oocyte maturation stages. Atresia affected 48-55 % of the initial number of oocytes. The maximum observed potential fecundity was estimated at 250-300 eggs. G. macrotyla showed a group-synchronous ovulation pattern, regulative atresia, and a batching spawning pattern with a few egg batches spawned intermittently over an extended period of spawning.

  11. Ultra-fast escape maneuver of an octopus-inspired robot.

    PubMed

    Weymouth, G D; Subramaniam, V; Triantafyllou, M S

    2015-02-02

    We design and test an octopus-inspired flexible hull robot that demonstrates outstanding fast-starting performance. The robot is hyper-inflated with water, and then rapidly deflates to expel the fluid so as to power the escape maneuver. Using this robot we verify for the first time in laboratory testing that rapid size-change can substantially reduce separation in bluff bodies traveling several body lengths, and recover fluid energy which can be employed to improve the propulsive performance. The robot is found to experience speeds over ten body lengths per second, exceeding that of a similarly propelled optimally streamlined rigid rocket. The peak net thrust force on the robot is more than 2.6 times that on an optimal rigid body performing the same maneuver, experimentally demonstrating large energy recovery and enabling acceleration greater than 14 body lengths per second squared. Finally, over 53% of the available energy is converted into payload kinetic energy, a performance that exceeds the estimated energy conversion efficiency of fast-starting fish. The Reynolds number based on final speed and robot length is [Formula: see text]. We use the experimental data to establish a fundamental deflation scaling parameter [Formula: see text] which characterizes the mechanisms of flow control via shape change. Based on this scaling parameter, we find that the fast-starting performance improves with increasing size.

  12. Electron-microscopic observations of the gravity receptor epithelia of normal and spinner juvenile Octopus maya.

    PubMed

    Fermin, C D; Colmers, W F; Igarashi, M

    1985-01-01

    Light and electron microscopy of the gravity receptor epithelia (maculae) of statocysts of normal and "spinner" juvenile Octopus maya showed differences between the structures of the hair cells, supporting cells, and afferent neurons of these cephalopods. The maculae of spinner animals were approximately 30% smaller in their surface area and had 40% fewer hair cells. Moreover, the average distance between randomly-chosen hair bundles in scanning electron micrographs of maculae of normal animals was significantly greater (4.33 +/- 6.47 microns) than those of maculae of spinner animals (3.38 +/- 4.90 microns; P less than 0.0001). The sectional area of the supporting cell's microvilli in spinner maculae was larger (0.16 +/- 0.18 microns) than those of normal (0.10 +/- 0.10 micron; P less than 0.0001) O. maya. The morphological differences observed between certain structural components of the maculae of normal and spinner O. maya may be related to the absence and/or malformation of the neuroepithelial suprastructures in spinners. This may have direct or indirect effects to their inability to orient to gravity with these organs. PMID:2861903

  13. OCTOPUS Negatively Regulates BIN2 to Control Phloem Differentiation in Arabidopsis thaliana.

    PubMed

    Anne, Pauline; Azzopardi, Marianne; Gissot, Lionel; Beaubiat, Sébastien; Hématy, Kian; Palauqui, Jean-Christophe

    2015-10-01

    The phloem is a vascular strand that conducts photoassimilates and systemic signals throughout the plant to coordinate growth. To date, few molecular genetic determinants have been identified to control both specification and differentiation of this tissue [1-3]. Among them, OCTOPUS (OPS) protein was previously identified as a polarly localized plasma membrane-associated protein of unknown biochemical function whose broad provascular expression becomes restricted to the phloem upon differentiation [2]. OPS loss-of-function mutants showed an altered vascular network in cotyledons and an intermittent phloem differentiation in the root [2, 4]. Here, we demonstrate a role for OPS as a positive regulator of the brassinosteroid (BR) signaling pathway. Indeed, transgenic lines overexpressing OPS (OPS-OE) display the hallmarks of constitutively overactivated BR mutants. Physiological and genetic analyses place OPS as a positive regulator of the BR signaling pathway upstream of the key transcription factors BES1 and BZR1. Directed protein interactions with known BR signaling proteins identified BIN2, a GSK3 protein involved in multiple signaling pathways, as a partner of OPS. This interaction recruits BIN2 to the plasma membrane, thus preventing its inhibitory activity in the nucleus. Finally, both bikinin (a potent inhibitor of GSK3 [5]) treatment and downstream dominant mutants bes1-D [6] and bzr1-D [7] can rescue phloem defects of ops in the root. Together, our data show that OPS antagonizes BIN2 to promote phloem differentiation. PMID:26387715

  14. An octopus toxin, maculotoxin, selectively blocks sodium current in squid axons.

    PubMed Central

    Gage, P W; Moore, J W; Westerfield, M

    1976-01-01

    1. A low molecular weight, stable, cationic neurotoxin (maculotoxin, MTX) extracted from the posterior salivary glands of the octopus Hapalochlaena maculosa, blocked sodium current in voltage-clamped squid axons without affecting potassium current. 2. The effectiveness of MTX was increased by repetitive, brief, depolarizing pulses but not by a single prolonged depolarization. 3. The potency of MTX decreased at pHs from 8 to 9. Effectiveness could be restored be restored by lowering the pH to 7-1 again. It was concluded that MTX is active in its cationic form. 4. MTX affected sodium conductance kinetics, slowing the turn-on of sodium current. This effect was most noticeable with small deploarizations but became progressively less with larger depolarizations. Neither the turn-off of sodium current nor sodium inactivation kinetics were affected by the toxin. 5. MTX inhibited sodium current without inhibiting sodium gating current. 6. The effectiveness of MTX was not detectably changed when calcium concentration was varied from 50 to 10 mM, or sodium concentration was varied from 225 to 750 mM. PMID:957253

  15. Dynamics of underwater legged locomotion: modeling and experiments on an octopus-inspired robot.

    PubMed

    Calisti, M; Corucci, F; Arienti, A; Laschi, C

    2015-07-30

    This paper studies underwater legged locomotion (ULL) by means of a robotic octopus-inspired prototype and its associated model. Two different types of propulsive actions are embedded into the robot model: reaction forces due to leg contact with the ground and hydrodynamic forces such as the drag arising from the sculling motion of the legs. Dynamic parameters of the model are estimated by means of evolutionary techniques and subsequently the model is exploited to highlight some distinctive features of ULL. Specifically, the separation between the center of buoyancy (CoB)/center of mass and density affect the stability and speed of the robot, whereas the sculling movements contribute to propelling the robot even when its legs are detached from the ground. The relevance of these effects is demonstrated through robotic experiments and model simulations; moreover, by slightly changing the position of the CoB in the presence of the same feed-forward activation, a number of different behaviors (i.e. forward and backward locomotion at different speeds) are achieved.

  16. The ultrastructure of the spermatozoon of Octopus ocellatus Gray, 1849 (Cephalopoda: Octopoda)

    NASA Astrophysics Data System (ADS)

    Yang, Jianmin; Wang, Weijun; Zheng, Xiaodong; Zhou, Quanli; Zhang, Yu; Sun, Guohua; Liu, Xiangquan

    2011-01-01

    Morphology of the spermatozoon of Octopus ocellatus was studied by light, scanning electron, and transmission electron microscopes. Sperm are 600-700 μm long, with a large number of granules in diameter about 130 nm. Each spermatozoon is composed of a head, neck, and tail. The head is made up of an acrosomal complex anterior to the nucleus. The spiral acrosomal complex consists of an electron-lucent vesicle, lacuna, and an electron-dense acrosomal vesicle. Additionally, the spiral acrosomal vesicle has numerous equidistant striations, and is surrounded by many small granules (20 nm diameter). A long straight nucleus, which is electron-densed, has a deep posterior concavity, the nuclear vacuole. At the terminal end of the nucleus is a sleeve-like structure with a concave posterior nuclear fossa (PNF). The neck is short connecting the PNF. The basal body is located in the PNF and gives rise to the axoneme. This structure connects the head, neck, and tail. The tail is divided into a middle piece and a principal piece. The middle piece, having a 9+9+2 arrangement, is surrounded by a mitochondrial sheath and terminates by an electron-dense fibrous sheath. The principal piece is the longest part of the sperm with coarse fibers tapering posteriorly. The results of this study shall provide some useful information for artificial breeding of this species.

  17. Vault-poly-ADP-ribose polymerase in the Octopus vulgaris brain: a regulatory factor of actin polymerization dynamic.

    PubMed

    De Maio, Anna; Natale, Emiliana; Rotondo, Sergio; Di Cosmo, Anna; Faraone-Mennella, Maria Rosaria

    2013-09-01

    Our previous behavioural, biochemical and immunohistochemical analyses conducted in selected regions (supra/sub oesophageal masses) of the Octopus vulgaris brain detected a cytoplasmic poly-ADP-ribose polymerase (more than 90% of total enzyme activity). The protein was identified as the vault-free form of vault-poly-ADP-ribose polymerase. The present research extends and integrates the biochemical characterization of poly-ADP-ribosylation system, namely, reaction product, i.e., poly-ADP-ribose, and acceptor proteins, in the O. vulgaris brain. Immunochemical analyses evidenced that the sole poly-ADP-ribose acceptor was the octopus cytoskeleton 50-kDa actin. It was present in both free, endogenously poly-ADP-ribosylated form (70kDa) and in complex with V-poly-ADP-ribose polymerase and poly-ADP-ribose (260kDa). The components of this complex, alkali and high salt sensitive, were purified and characterized. The kind and the length of poly-ADP-ribose corresponded to linear chains of 30-35 ADP-ribose units, in accordance with the features of the polymer synthesized by the known vault-poly-ADP-ribose polymerase. In vitro experiments showed that V-poly-ADP-ribose polymerase activity of brain cytoplasmic fraction containing endogenous actin increased upon the addition of commercial actin and was highly reduced by ATP. Anti-actin immunoblot of the mixture in the presence and absence of ATP showed that the poly-ADP-ribosylation of octopus actin is a dynamic process balanced by the ATP-dependent polymerization of the cytoskeleton protein, a fundamental mechanism for synaptic plasticity.

  18. Structure formation in binary mixtures of surfactants: vesicle opening-up to bicelles and octopus-like micelles

    NASA Astrophysics Data System (ADS)

    Noguchi, Hiroshi

    Micelle formation in binary mixtures of surfactants is studied using a coarse-grained molecular simulation. When a vesicle composed of lipid and detergent types of molecules is ruptured, a disk-shaped micelle, the bicelle, is typically formed. It is found that cup-shaped vesicles and bicelles connected with worm-like micelles are also formed depending on the surfactant ratio and critical micelle concentration. The obtained octopus shape of micelles agree with those observed in the cryo-TEM images reported in [S. Jain and F. S. Bates, Macromol. 37, 1511 (2004).]. Two types of connection structures between the worm-like micelles and the bicelles are revealed.

  19. Rapid method for controlling the correct labeling of products containing common octopus (Octopus vulgaris) and main substitute species (Eledone cirrhosa and Dosidicus gigas) by fast real-time PCR.

    PubMed

    Espiñeira, Montserrat; Vieites, Juan M

    2012-12-15

    The TaqMan real-time PCR has the highest potential for automation, therefore representing the currently most suitable method for screening, allowing the detection of fraudulent or unintentional mislabeling of species. This work describes the development of a real-time polymerase chain reaction (RT-PCR) system for the detection and identification of common octopus (Octopus vulgaris) and main substitute species (Eledone cirrhosa and Dosidicus gigas). This technique is notable for the combination of simplicity, speed, sensitivity and specificity in an homogeneous assay. The method can be applied to all kinds of products; fresh, frozen and processed, including those undergoing intensive processes of transformation. This methodology was validated to check how the degree of food processing affects the method and the detection of each species. Moreover, it was applied to 34 commercial samples to evaluate the labeling of products made from them. The methodology herein developed is useful to check the fulfillment of labeling regulations for seafood products and to verify traceability in commercial trade and for fisheries control.

  20. Rapid method for controlling the correct labeling of products containing common octopus (Octopus vulgaris) and main substitute species (Eledone cirrhosa and Dosidicus gigas) by fast real-time PCR.

    PubMed

    Espiñeira, Montserrat; Vieites, Juan M

    2012-12-15

    The TaqMan real-time PCR has the highest potential for automation, therefore representing the currently most suitable method for screening, allowing the detection of fraudulent or unintentional mislabeling of species. This work describes the development of a real-time polymerase chain reaction (RT-PCR) system for the detection and identification of common octopus (Octopus vulgaris) and main substitute species (Eledone cirrhosa and Dosidicus gigas). This technique is notable for the combination of simplicity, speed, sensitivity and specificity in an homogeneous assay. The method can be applied to all kinds of products; fresh, frozen and processed, including those undergoing intensive processes of transformation. This methodology was validated to check how the degree of food processing affects the method and the detection of each species. Moreover, it was applied to 34 commercial samples to evaluate the labeling of products made from them. The methodology herein developed is useful to check the fulfillment of labeling regulations for seafood products and to verify traceability in commercial trade and for fisheries control. PMID:22980826

  1. Sequence of the Octopus dofleini hemocyanin subunit: structural and evolutionary implications.

    PubMed

    Miller, K I; Cuff, M E; Lang, W F; Varga-Weisz, P; Field, K G; van Holde, K E

    1998-05-15

    Sequencing of the subunit of the hemocyanin of Octopus dofleini has been completed from a cDNA library. This represents the first molluscan hemocyanin to be completely sequenced. The sequence determined is for one of the two distinguishable cDNAs which have been recognized for this protein. The protein subunit has 2896 amino acids and contains seven functional units, each carrying two sets of three invariant histidine residues constituting the binding sites (A and B) for two copper atoms. The accompanying paper identifies this site in the C-terminal functional unit (Odg). Differences in sequence for the two cDNAs, for the region in which both are available, are concentrated in the "linker regions" between functional units. The sequences of the seven units exhibit high similarity, averaging about 40% identity, with a concentration of conserved sequences in the region surrounding the copper binding sites. The sequences around the B-site show significant homology to the sequences of arthropod hemocyanins. Comparison of the functional unit sequences in terms of hydrophobicity and surface exposure profiles, as well as regions of probable secondary structure, indicate that all functional units probably have a common tertiary folding; the protein subunit is a string of similarly folded beads. A number of putative N-linked carbohydrate binding sites can be recognized in the sequence; one of these corresponds to the carbohydrate observed in the X-ray diffraction study of functional unit Odg as disclosed in the accompying paper. Phylogenetic analysis of the sequences of the O. dofleini functional units, and comparison with other available molluscan sequences indicates that the multi-domain subunit structure must have arisen over a relatively brief period, preceeding the differentiation of major molluscan types. PMID:9614945

  2. Expression analysis of HSP70 in the testis of Octopus tankahkeei under thermal stress.

    PubMed

    Long, Ling-Li; Han, Ying-Li; Sheng, Zhang; Du, Chen; Wang, You-Fa; Zhu, Jun-Quan

    2015-09-01

    The gene encoding heat shock protein 70 (HSP70) was identified in Octopus tankahkeei by homologous cloning and rapid amplification of cDNA ends (RACE). The full-length cDNA (2471 bp) consists of a 5'-untranslated region (UTR) (89 bp), a 3'-UTR (426 bp), and an open reading frame (1956 bp) that encodes 651 amino acid residues with a predicted molecular mass of 71.8 kDa and an isoelectric point of 5.34. Based on the amino acid sequence analysis and multiple sequence alignment, this cDNA is a member of cytoplasmic hsp70 subfamily of the hsp70 family and was designated as ot-hsp70. Tissue expression analysis showed that HSP70 expression is highest in the testes when all examined organs were compared. Immunohistochemistry analysis, together with hematoxylin-eosin staining, revealed that the HSP70 protein was expressed in all spermatogenic cells, but not in fibroblasts. In addition, O. tankahkeei were heat challenged by exposure to 32 °C seawater for 2 h, then returned to 13 °C for various recovery time (0-24 h). Relative expression of ot-hsp70 mRNA in the testes was measured at different time points post-challenge by quantitative real-time PCR. A clear time-dependent mRNA expression of ot-hsp70 after thermal stress indicates that the HSP70 gene is inducible. Ultrastructural changes of the heat-stressed testis were observed by transmission electron microscopy. We suggest that HSP70 plays an important role in spermatogenesis and testis protection against thermal stress in O. tankahkeei. PMID:26033497

  3. Expression analysis of HSP70 in the testis of Octopus tankahkeei under thermal stress.

    PubMed

    Long, Ling-Li; Han, Ying-Li; Sheng, Zhang; Du, Chen; Wang, You-Fa; Zhu, Jun-Quan

    2015-09-01

    The gene encoding heat shock protein 70 (HSP70) was identified in Octopus tankahkeei by homologous cloning and rapid amplification of cDNA ends (RACE). The full-length cDNA (2471 bp) consists of a 5'-untranslated region (UTR) (89 bp), a 3'-UTR (426 bp), and an open reading frame (1956 bp) that encodes 651 amino acid residues with a predicted molecular mass of 71.8 kDa and an isoelectric point of 5.34. Based on the amino acid sequence analysis and multiple sequence alignment, this cDNA is a member of cytoplasmic hsp70 subfamily of the hsp70 family and was designated as ot-hsp70. Tissue expression analysis showed that HSP70 expression is highest in the testes when all examined organs were compared. Immunohistochemistry analysis, together with hematoxylin-eosin staining, revealed that the HSP70 protein was expressed in all spermatogenic cells, but not in fibroblasts. In addition, O. tankahkeei were heat challenged by exposure to 32 °C seawater for 2 h, then returned to 13 °C for various recovery time (0-24 h). Relative expression of ot-hsp70 mRNA in the testes was measured at different time points post-challenge by quantitative real-time PCR. A clear time-dependent mRNA expression of ot-hsp70 after thermal stress indicates that the HSP70 gene is inducible. Ultrastructural changes of the heat-stressed testis were observed by transmission electron microscopy. We suggest that HSP70 plays an important role in spermatogenesis and testis protection against thermal stress in O. tankahkeei.

  4. Octopus S-crystallins with endogenous glutathione S-transferase (GST) activity: sequence comparison and evolutionary relationships with authentic GST enzymes.

    PubMed Central

    Chiou, S H; Yu, C W; Lin, C W; Pan, F M; Lu, S F; Lee, H J; Chang, G G

    1995-01-01

    S-Crystallin is a major protein present in the lenses of cephalopods (octopus and squid). To facilitate the cloning of this crystallin gene, cDNA was constructed from the poly(A)+ mRNA of octopus lenses, and amplified by PCR for nucleotide sequencing. Sequencing of 10 of 15 positive clones coding for this crystallin revealed three distinct S-crystallin isoforms with 61-64% identity in nucleotide sequences and 42-58% similarity in amino acid sequences when compared with homologous crystallins in squid lenses. These charge-isomeric crystallins also show between 26 and 33% amino acid sequence identity to four major classes of glutathione S-transferase (GST), a major detoxification enzyme present in most mammalian tissues. For further analysis, expression of one of the S-crystallin cDNAs was carried out in the bacterial expression system pQE-30, and the S-crystallin protein produced in Escherichia coli was purified to homogeneity to determine the enzymic properties. We found that the expressed octopus S-crystallin possessed much lower GST activity than the authentic GSTs from other tissues. Sequence comparison and construction of phylogenetic trees for S-crystallins from squid and octopus lenses and various classes of GSTs revealed that S-crystallins represent a multigene family which is structurally related to Alpha-class GSTs and probably derived from the ancestral GST by gene duplication and subsequent multiple mutational substitutions. Images Figure 2 Figure 3 Figure 6 Figure 7 PMID:7639695

  5. [Comparative visual field study using the Octopus 2,000R with the global analysis program G1 with the grid pattern].

    PubMed

    Kieselbach, G F; Juen, S

    1988-01-01

    At the Universitäts-Augenklinik Innsbruck patients with diabetic macular edema are treated with grid pattern since February 1986. Thirty-two eyes from 18 patients were tested with the program G1 on perimeter Octopus 2000R before and after grid pattern. The evaluated parameters presented by the program G1 are discussed. PMID:3362513

  6. Intra-organismal distribution of tetrodotoxin in two species of blue-ringed octopuses (Hapalochlaena fasciata and H. lunulata).

    PubMed

    Williams, Becky L; Caldwell, Roy L

    2009-09-01

    In-depth studies on the intra-organismal distribution of toxin may yield valuable clues about potential ecological functions. The distribution of tetrodotoxin (TTX) in previously unexamined tissues of two species of blue-ringed octopuses, wild-caught Hapalochlaena fasciata and Hapalochlaena lunulata from the aquarium industry, was surveyed. Tissues from each individual were examined separately. Tetrodotoxin was detected in posterior salivary gland (PSG), arm, mantle, anterior salivary glands, digestive gland, testes contents, brachial heart, nephridia, gill, and oviducal gland of H. fasciata. By contrast TTX was found only in the PSG, mantle tissue, and ink of H. lunulata. The highest concentrations of TTX resided in the PSG of both species; however, the arms and mantle contained the greatest absolute amounts of TTX. Minimum total amounts of TTX per octopus ranged from 60 to 405 microg in H. fasciata and from 0 to 174 microg in H. lunulata and correlated well with the amounts in the PSG. Transport of TTX in the blood is loosely suggested by the presence of the toxin in blood-rich organs such as the gill and brachial hearts. The distributional data also suggest both offensive and defensive functions of TTX.

  7. DNA damage and metal accumulation in four tissues of feral Octopus vulgaris from two coastal areas in Portugal.

    PubMed

    Raimundo, Joana; Costa, Pedro M; Vale, Carlos; Costa, Maria Helena; Moura, Isabel

    2010-10-01

    The alkaline comet assay has been employed for the first time to estimate the basal DNA damage in the digestive gland, gills, kidney and gonads of Octopus vulgaris. Octopuses were captured in two coastal areas adjacent to the cities of Matosinhos (N) and Olhão (S), Portugal. The area of Matosinhos is influenced by discharges of the Douro River, city of Porto, industries and intensive agriculture, while Olhão is an important fisheries port. Previous works point to contrasting metal availability in the two coastal areas. Among the analysed tissues digestive gland presented the highest levels of Zn, Cu, Cd and Pb. Tissues of specimens from Matosinhos exhibited high levels of Cd and from Olhão enhanced Pb concentrations. The DNA damages in digestive gland, gills and kidney were more accentuated in specimens from Matosinhos than from Olhão, suggesting a stronger effect of contaminants. Elevated strand breakages were registered in digestive gland, recognised for its ability to store and detoxify accumulated metals. The DNA damages in kidney, gills and gonads were lower, reflecting reduced metal accumulation or efficient detoxification. The broad variability of damages in the three tissues may also mirror tissue function, specific defences to genotoxicants and cell-cycle turnover.

  8. Quaternary Structure Heterogeneity of Oligomeric Proteins: A SAXS and SANS Study of the Dissociation Products of Octopus vulgaris Hemocyanin

    PubMed Central

    Spinozzi, Francesco; Mariani, Paolo; Mičetić, Ivan; Ferrero, Claudio; Pontoni, Diego; Beltramini, Mariano

    2012-01-01

    Octopus vulgaris hemocyanin shows a particular self-assembling pattern, characterized by a hierarchical organization of monomers. The highest molecular weight aggregate is a decamer, the stability of which in solution depends on several parameters. Different pH values, buffer compositions, H2O/D2O ratios and Hofmeister’s salts result in modifications of the aggregation state of Octopus vulgaris hemocyanin. The new QUAFIT method, recently applied to derive the structure of the decameric and the monomeric assembly from small-angle scattering data, is used here to model the polydisperse system that results from changing the solution conditions. A dataset of small-angle X-rays and neutron scattering curves is analysed by QUAFIT to derive structure, composition and concentration of different assemblies present in solution. According to the hierarchy of the association/dissociation processes and the possible number of different aggregation products in solution, each sample has been considered as a heterogeneous mixture composed of the entire decamer, the dissociated “loose” monomer and all the intermediate dissociation products. Scattering curves corresponding to given experimental conditions are well fitted by using a linear combination of single particle form factors. QUAFIT has proved to be a method of general validity to describe solutions of proteins that, even after purification processes, result to be intrinsically heterogeneous. PMID:23166737

  9. Genetic differentiation of Octopus minor (Mollusca, Cephalopoda) off the northern coast of China as revealed by amplified fragment length polymorphisms.

    PubMed

    Yang, J M; Sun, G H; Zheng, X D; Ren, L H; Wang, W J; Li, G R; Sun, B C

    2015-01-01

    Octopus minor (Sasaki, 1920) is an economically important cephalopod that is found in the northern coastal waters of China. In this study, we investigated genetic differentiation in fishery populations using amplified fragment length polymorphisms (AFLPs). A total of 150 individuals were collected from five locations: Dalian (DL), Yan-tai (YT), Qingdao (QD), Lianyungang (LY), and Zhoushan (ZS), and 243 reproducible bands were amplified using five AFLP primer combinations. The percentage of polymorphic bands ranged from 53.33 to 76.08%. Nei's genetic identity ranged from 0.9139 to 0.9713, and the genetic distance ranged from 0.0291 to 0.0900. A phylogenetic tree was constructed using the unweighted pair group method with arithmetic mean, based on the genetic distance. The DL and YT populations originated from one clade, while the QD, LY, and ZS populations originated from another. The results indicate that the O. minor stock consisted of two genetic populations with an overall significantly analogous FST value (0.1088, P < 0.05). Most of the variance was within populations. These findings will be important for more sustainable octopus fisheries, so that this marine resource can be conserved for its long-term utilization. PMID:26634529

  10. Two new species of dicyemid mesozoans (Dicyemida: Dicyemidae) from Octopus maya Voss & Solis-Ramirez (Octopodidae) off Yucatan, Mexico.

    PubMed

    Castellanos-Martinez, Sheila; Aguirre-Macedo, M Leopoldina; Furuya, Hidetaka

    2016-07-01

    Two new dicyemid species are described from the endemic cephalopod Octopus maya Voss & Solis-Ramirez collected off Yucatan, Mexico. The renal sacs of 40 juvenile and adult octopuses from four localities were examined. Dicyema hochbergi n. sp. is a medium-sized species that reaches 2,245 µm in length. The vermiform stages consist of 18-24 peripheral cells, a conical calotte and the extension of the axial cell between the base and middle of the metapolar cells. Infusoriform embryos consist of 39 cells with urn cell containing one germinal cell, two nuclei and solid refringent bodies. Dicyema mexcayae n. sp. is a relatively small species that reaches 1,114 µm in length. The vermiform stages are constituted by 14-16 peripheral cells, an elongate calotte and the axial cell extending forward to the middle of the metapolar cells. The infusoriform embryos consist of 37 cells, two solid refringent bodies and urn cells with two nuclei each. The present study represents the first description of a dicyemid species from O. maya and increases the number of described species from Mexican waters to 11. PMID:27307168

  11. Characterization of proteases from Planomicrobium sp. L-2 isolated from the gastrointestinal tract of Octopus variabilis (Sasaki)

    NASA Astrophysics Data System (ADS)

    Jin, Yulan; Wang, Yurong; Xiao, Lin; Lin, Xiukun

    2016-05-01

    A crude protease produced from Planomicrobium sp. L-2 is described, and its effectiveness as an additive in liquid detergent evaluated. We isolate the protease-producing Planomicrobium sp. L-2 from the gastrointestinal tract of Octopus variabilis. At least three caseinolytic protease clear bands were observed in zymogram analysis. The crude alkaline protease was highly tolerant of a pH range from 7.0 to 9.0, and temperatures to 50°C after incubation for 1 h. Proteolytic enzymes were stable towards three surfactants (5% Tween 80, 1% Triton X-100 and 0.05% SDS) and an oxidizing agent (1% hydrogen peroxide), in addition to being highly stable and compatible with popular commercial laundry powered detergent brands available in China. Our study demonstrates the potential these proteases have for development into novel classes of detergent additive. This study also suggests that the gastrointestinal tract of Octopus variabilis may be a rich source of commercially valuable strains of enzyme.

  12. Using Age-Based Life History Data to Investigate the Life Cycle and Vulnerability of Octopus cyanea

    PubMed Central

    Herwig, Jade N.; Depczynski, Martial; Roberts, John D.; Semmens, Jayson M.; Gagliano, Monica; Heyward, Andrew J.

    2012-01-01

    Octopus cyanea is taken as an unregulated, recreationally fished species from the intertidal reefs of Ningaloo, Western Australia. Yet despite its exploitation and importance in many artisanal fisheries throughout the world, little is known about its life history, ecology and vulnerability. We used stylet increment analysis to age a wild O. cyanea population for the first time and gonad histology to examine their reproductive characteristics. O. cyanea conforms to many cephalopod life history generalisations having rapid, non-asymptotic growth, a short life-span and high levels of mortality. Males were found to mature at much younger ages and sizes than females with reproductive activity concentrated in the spring and summer months. The female dominated sex-ratios in association with female brooding behaviours also suggest that larger conspicuous females may be more prone to capture and suggests that this intertidal octopus population has the potential to be negatively impacted in an unregulated fishery. Size at age and maturity comparisons between our temperate bordering population and lower latitude Tanzanian and Hawaiian populations indicated stark differences in growth rates that correlate with water temperatures. The variability in life history traits between global populations suggests that management of O. cyanea populations should be tailored to each unique set of life history characteristics and that stylet increment analysis may provide the integrity needed to accurately assess this. PMID:22912898

  13. Two new species of dicyemid mesozoans (Dicyemida: Dicyemidae) from Octopus maya Voss & Solis-Ramirez (Octopodidae) off Yucatan, Mexico.

    PubMed

    Castellanos-Martinez, Sheila; Aguirre-Macedo, M Leopoldina; Furuya, Hidetaka

    2016-07-01

    Two new dicyemid species are described from the endemic cephalopod Octopus maya Voss & Solis-Ramirez collected off Yucatan, Mexico. The renal sacs of 40 juvenile and adult octopuses from four localities were examined. Dicyema hochbergi n. sp. is a medium-sized species that reaches 2,245 µm in length. The vermiform stages consist of 18-24 peripheral cells, a conical calotte and the extension of the axial cell between the base and middle of the metapolar cells. Infusoriform embryos consist of 39 cells with urn cell containing one germinal cell, two nuclei and solid refringent bodies. Dicyema mexcayae n. sp. is a relatively small species that reaches 1,114 µm in length. The vermiform stages are constituted by 14-16 peripheral cells, an elongate calotte and the axial cell extending forward to the middle of the metapolar cells. The infusoriform embryos consist of 37 cells, two solid refringent bodies and urn cells with two nuclei each. The present study represents the first description of a dicyemid species from O. maya and increases the number of described species from Mexican waters to 11.

  14. Genetic differentiation of Octopus minor (Mollusca, Cephalopoda) off the northern coast of China as revealed by amplified fragment length polymorphisms.

    PubMed

    Yang, J M; Sun, G H; Zheng, X D; Ren, L H; Wang, W J; Li, G R; Sun, B C

    2015-12-02

    Octopus minor (Sasaki, 1920) is an economically important cephalopod that is found in the northern coastal waters of China. In this study, we investigated genetic differentiation in fishery populations using amplified fragment length polymorphisms (AFLPs). A total of 150 individuals were collected from five locations: Dalian (DL), Yan-tai (YT), Qingdao (QD), Lianyungang (LY), and Zhoushan (ZS), and 243 reproducible bands were amplified using five AFLP primer combinations. The percentage of polymorphic bands ranged from 53.33 to 76.08%. Nei's genetic identity ranged from 0.9139 to 0.9713, and the genetic distance ranged from 0.0291 to 0.0900. A phylogenetic tree was constructed using the unweighted pair group method with arithmetic mean, based on the genetic distance. The DL and YT populations originated from one clade, while the QD, LY, and ZS populations originated from another. The results indicate that the O. minor stock consisted of two genetic populations with an overall significantly analogous FST value (0.1088, P < 0.05). Most of the variance was within populations. These findings will be important for more sustainable octopus fisheries, so that this marine resource can be conserved for its long-term utilization.

  15. Intra-organismal distribution of tetrodotoxin in two species of blue-ringed octopuses (Hapalochlaena fasciata and H. lunulata).

    PubMed

    Williams, Becky L; Caldwell, Roy L

    2009-09-01

    In-depth studies on the intra-organismal distribution of toxin may yield valuable clues about potential ecological functions. The distribution of tetrodotoxin (TTX) in previously unexamined tissues of two species of blue-ringed octopuses, wild-caught Hapalochlaena fasciata and Hapalochlaena lunulata from the aquarium industry, was surveyed. Tissues from each individual were examined separately. Tetrodotoxin was detected in posterior salivary gland (PSG), arm, mantle, anterior salivary glands, digestive gland, testes contents, brachial heart, nephridia, gill, and oviducal gland of H. fasciata. By contrast TTX was found only in the PSG, mantle tissue, and ink of H. lunulata. The highest concentrations of TTX resided in the PSG of both species; however, the arms and mantle contained the greatest absolute amounts of TTX. Minimum total amounts of TTX per octopus ranged from 60 to 405 microg in H. fasciata and from 0 to 174 microg in H. lunulata and correlated well with the amounts in the PSG. Transport of TTX in the blood is loosely suggested by the presence of the toxin in blood-rich organs such as the gill and brachial hearts. The distributional data also suggest both offensive and defensive functions of TTX. PMID:19481562

  16. Differential postsynaptic distribution of GluRs 1-4 on cartwheel and octopus cell somata in the gerbil cochlear nucleus.

    PubMed

    Schwartz, I R; Keh, A; Eager, P R

    2000-09-01

    Differences were demonstrated in the distribution of glutamate receptors (GluR) 1, 2, 2/3 and 4 postsynaptic immunoreactivity (PSIR) on the somata of cartwheel and octopus cells in the adult gerbil cochlear nucleus (CN). Montages of electron micrographs of cartwheel and octopus cells immunoreacted with antibodies to GluR 1, 2, 2/3 and 4 were prepared. The number of synaptic terminals with PSIR were counted on all cells for each antibody, normalized to the total length of somatic surface analyzed. The density of terminals apposed to PSIR on octopus cells was similar for the antibodies GluR1, 2/3 and 4, but significantly less for GluR2. On cartwheel somata the numbers of terminals apposed to immunoreactive postsynaptic specializations with GluR1, 2, 2/3 or 4 were not significantly different from each other. The density of terminals apposed to GluR2/3 and 4 positive postsynaptic specializations was significantly less on cartwheel cells than on octopus somata. The data suggest that the decreased presence of the GluR2 subunit, which confers calcium impermeability to the assembled receptor and slower gating kinetics to receptors with a high GluR4 content, is the major difference in the AMPA receptors on the somata of these cell types. The presence on cartwheel cells of a majority of AMPA receptors which contain GluR2 may account for the fact that cartwheel cells respond to shocks to the auditory nerve with 100 ms excitatory postsynaptic potentials (EPSPs), while octopus cells, most of whose AMPA receptors lack GluR2, respond with 1 ms EPSPs.

  17. Positive Catch & Economic Benefits of Periodic Octopus Fishery Closures: Do Effective, Narrowly Targeted Actions ‘Catalyze’ Broader Management?

    PubMed Central

    Oliver, Thomas A.; Oleson, Kirsten L. L.; Ratsimbazafy, Hajanaina; Raberinary, Daniel; Benbow, Sophie; Harris, Alasdair

    2015-01-01

    Overview Eight years of octopus fishery records from southwest Madagascar reveal significant positive impacts from 36 periodic closures on: (a) fishery catches and (b) village fishery income, such that (c) economic benefits from increased landings outweigh costs of foregone catch. Closures covered ~20% of a village’s fished area and lasted 2-7 months. Fishery Catches from Each Closed Site Octopus landings and catch per unit effort (CPUE) significantly increased in the 30 days following a closure’s reopening, relative to the 30 days before a closure (landings: +718%, p<0.0001; CPUE: +87%, p<0.0001; n = 36). Open-access control sites showed no before/after change when they occurred independently of other management (“no ban”, n = 17/36). On the other hand, open-access control sites showed modest catch increases when they extended a 6-week seasonal fishery shutdown (“ban”, n = 19/36). The seasonal fishery shutdown affects the entire region, so confound all potential control sites. Fishery Income in Implementing Villages In villages implementing a closure, octopus fishery income doubled in the 30 days after a closure, relative to 30 days before (+132%, p<0.001, n = 28). Control villages not implementing a closure showed no increase in income after “no ban” closures and modest increases after “ban” closures. Villages did not show a significant decline in income during closure events. Net Economic Benefits from Each Closed Site Landings in closure sites generated more revenue than simulated landings assuming continued open-access fishing at that site (27/36 show positive net earnings; mean +$305/closure; mean +57.7% monthly). Benefits accrued faster than local fishers’ time preferences during 17-27 of the 36 closures. High reported rates of illegal fishing during closures correlated with poor economic performance. Broader Co-Management We discuss the implications of our findings for broader co-management arrangements, particularly for catalyzing

  18. Assembly of Octopus dofleini hemocyanin. A study of the kinetics by sedimentation, light scattering and electron microscopy.

    PubMed

    van Holde, K E; Miller, K; Schabtach, E; Libertini, L

    1991-01-20

    The kinetics of association of Octopus dofleini hemocyanin subunits to form the native decameric molecule have been studied with a combination of sedimentation, light scattering and electron microscopy. The reaction, initiated by addition of magnesium, is relatively slow, requiring hours to reach completion, with monomer and decamer as predominant molecular species throughout. Analysis of the light-scattering data, including stopped-flow studies, reveals an initial lag period in the reaction, followed by a second-order process that is rate limiting. The lag period depends on both protein and magnesium ion concentration. Electron microscope studies reveal intermediates in the process, and support a model of assembly in which nucleation begins at the dimer level. Theoretical models for the process are compared. PMID:1992165

  19. Real-space grids and the Octopus code as tools for the development of new simulation approaches for electronic systems.

    PubMed

    Andrade, Xavier; Strubbe, David; De Giovannini, Umberto; Larsen, Ask Hjorth; Oliveira, Micael J T; Alberdi-Rodriguez, Joseba; Varas, Alejandro; Theophilou, Iris; Helbig, Nicole; Verstraete, Matthieu J; Stella, Lorenzo; Nogueira, Fernando; Aspuru-Guzik, Alán; Castro, Alberto; Marques, Miguel A L; Rubio, Angel

    2015-12-21

    Real-space grids are a powerful alternative for the simulation of electronic systems. One of the main advantages of the approach is the flexibility and simplicity of working directly in real space where the different fields are discretized on a grid, combined with competitive numerical performance and great potential for parallelization. These properties constitute a great advantage at the time of implementing and testing new physical models. Based on our experience with the Octopus code, in this article we discuss how the real-space approach has allowed for the recent development of new ideas for the simulation of electronic systems. Among these applications are approaches to calculate response properties, modeling of photoemission, optimal control of quantum systems, simulation of plasmonic systems, and the exact solution of the Schrödinger equation for low-dimensionality systems.

  20. Real-space grids and the Octopus code as tools for the development of new simulation approaches for electronic systems

    NASA Astrophysics Data System (ADS)

    Andrade, Xavier; Strubbe, David; De Giovannini, Umberto; Larsen, Ask Hjorth; Oliveira, Micael J. T.; Alberdi-Rodriguez, Joseba; Varas, Alejandro; Theophilou, Iris; Helbig, Nicole; Verstraete, Matthieu J.; Stella, Lorenzo; Nogueira, Fernando; Aspuru-Guzik, Alán; Castro, Alberto; Marques, Miguel A. L.; Rubio, Angel

    Real-space grids are a powerful alternative for the simulation of electronic systems. One of the main advantages of the approach is the flexibility and simplicity of working directly in real space where the different fields are discretized on a grid, combined with competitive numerical performance and great potential for parallelization. These properties constitute a great advantage at the time of implementing and testing new physical models. Based on our experience with the Octopus code, in this article we discuss how the real-space approach has allowed for the recent development of new ideas for the simulation of electronic systems. Among these applications are approaches to calculate response properties, modeling of photoemission, optimal control of quantum systems, simulation of plasmonic systems, and the exact solution of the Schr\\"odinger equation for low-dimensionality systems.

  1. Real-space grids and the Octopus code as tools for the development of new simulation approaches for electronic systems.

    PubMed

    Andrade, Xavier; Strubbe, David; De Giovannini, Umberto; Larsen, Ask Hjorth; Oliveira, Micael J T; Alberdi-Rodriguez, Joseba; Varas, Alejandro; Theophilou, Iris; Helbig, Nicole; Verstraete, Matthieu J; Stella, Lorenzo; Nogueira, Fernando; Aspuru-Guzik, Alán; Castro, Alberto; Marques, Miguel A L; Rubio, Angel

    2015-12-21

    Real-space grids are a powerful alternative for the simulation of electronic systems. One of the main advantages of the approach is the flexibility and simplicity of working directly in real space where the different fields are discretized on a grid, combined with competitive numerical performance and great potential for parallelization. These properties constitute a great advantage at the time of implementing and testing new physical models. Based on our experience with the Octopus code, in this article we discuss how the real-space approach has allowed for the recent development of new ideas for the simulation of electronic systems. Among these applications are approaches to calculate response properties, modeling of photoemission, optimal control of quantum systems, simulation of plasmonic systems, and the exact solution of the Schrödinger equation for low-dimensionality systems. PMID:25721500

  2. Body size, growth and life span: implications for the polewards range shift of Octopus tetricus in south-eastern Australia.

    PubMed

    Ramos, Jorge E; Pecl, Gretta T; Moltschaniwskyj, Natalie A; Strugnell, Jan M; León, Rafael I; Semmens, Jayson M

    2014-01-01

    Understanding the response of any species to climate change can be challenging. However, in short-lived species the faster turnover of generations may facilitate the examination of responses associated with longer-term environmental change. Octopus tetricus, a commercially important species, has undergone a recent polewards range shift in the coastal waters of south-eastern Australia, thought to be associated with the southerly extension of the warm East Australian Current. At the cooler temperatures of a polewards distribution limit, growth of a species could be slower, potentially leading to a bigger body size and resulting in a slower population turnover, affecting population viability at the extreme of the distribution. Growth rates, body size, and life span of O. tetricus were examined at the leading edge of a polewards range shift in Tasmanian waters (40°S and 147°E) throughout 2011. Octopus tetricus had a relatively small body size and short lifespan of approximately 11 months that, despite cooler temperatures, would allow a high rate of population turnover and may facilitate the population increase necessary for successful establishment in the new extended area of the range. Temperature, food availability and gender appear to influence growth rate. Individuals that hatched during cooler and more productive conditions, but grew during warming conditions, exhibited faster growth rates and reached smaller body sizes than individuals that hatched into warmer waters but grew during cooling conditions. This study suggests that fast growth, small body size and associated rapid population turnover may facilitate the range shift of O. tetricus into Tasmanian waters.

  3. Body size, growth and life span: implications for the polewards range shift of Octopus tetricus in south-eastern Australia.

    PubMed

    Ramos, Jorge E; Pecl, Gretta T; Moltschaniwskyj, Natalie A; Strugnell, Jan M; León, Rafael I; Semmens, Jayson M

    2014-01-01

    Understanding the response of any species to climate change can be challenging. However, in short-lived species the faster turnover of generations may facilitate the examination of responses associated with longer-term environmental change. Octopus tetricus, a commercially important species, has undergone a recent polewards range shift in the coastal waters of south-eastern Australia, thought to be associated with the southerly extension of the warm East Australian Current. At the cooler temperatures of a polewards distribution limit, growth of a species could be slower, potentially leading to a bigger body size and resulting in a slower population turnover, affecting population viability at the extreme of the distribution. Growth rates, body size, and life span of O. tetricus were examined at the leading edge of a polewards range shift in Tasmanian waters (40°S and 147°E) throughout 2011. Octopus tetricus had a relatively small body size and short lifespan of approximately 11 months that, despite cooler temperatures, would allow a high rate of population turnover and may facilitate the population increase necessary for successful establishment in the new extended area of the range. Temperature, food availability and gender appear to influence growth rate. Individuals that hatched during cooler and more productive conditions, but grew during warming conditions, exhibited faster growth rates and reached smaller body sizes than individuals that hatched into warmer waters but grew during cooling conditions. This study suggests that fast growth, small body size and associated rapid population turnover may facilitate the range shift of O. tetricus into Tasmanian waters. PMID:25090250

  4. Dose-dependent effects of the clinical anesthetic isoflurane on Octopus vulgaris: a contribution to cephalopod welfare.

    PubMed

    Polese, Gianluca; Winlow, William; Di Cosmo, Anna

    2014-12-01

    Recent progress in animal welfare legislation relating to invertebrates has provoked interest in methods for the anesthesia of cephalopods, for which different approaches to anesthesia have been tried but in most cases without truly anesthetizing the animals. For example, several workers have used muscle relaxants or hypothermia as forms of "anesthesia." Several inhalational anesthetics are known to act in a dose-dependent manner on the great pond snail Lymnaea stagnalis, a pulmonate mollusk. Here we report, for the first time, on the effects of clinical doses of the well-known inhalational clinical anesthetic isoflurane on the behavioral responses of the common octopus Octopus vulgaris. In each experiment, isoflurane was equilibrated into a well-aerated seawater bath containing a single adult O. vulgaris. Using a web camera, we recorded each animal's response to touch stimuli eliciting withdrawal of the arms and siphon and observed changes in the respiratory rate and the chromatophore pattern over time (before, during, and after application of the anesthetic). We found that different animals of the same size responded with similar behavioral changes as the isoflurane concentration was gradually increased. After gradual application of 2% isoflurane for a maximum of 5 min (at which time all the responses indicated deep anesthesia), the animals recovered within 45-60 min in fresh aerated seawater. Based on previous findings in gastropods, we believe that the process of anesthesia induced by isoflurane is similar to that previously observed in Lymnaea. In this study we showed that isoflurane is a good, reversible anesthetic for O. vulgaris, and we developed a method for its use. PMID:25369208

  5. Dose-dependent effects of the clinical anesthetic isoflurane on Octopus vulgaris: a contribution to cephalopod welfare.

    PubMed

    Polese, Gianluca; Winlow, William; Di Cosmo, Anna

    2014-12-01

    Recent progress in animal welfare legislation relating to invertebrates has provoked interest in methods for the anesthesia of cephalopods, for which different approaches to anesthesia have been tried but in most cases without truly anesthetizing the animals. For example, several workers have used muscle relaxants or hypothermia as forms of "anesthesia." Several inhalational anesthetics are known to act in a dose-dependent manner on the great pond snail Lymnaea stagnalis, a pulmonate mollusk. Here we report, for the first time, on the effects of clinical doses of the well-known inhalational clinical anesthetic isoflurane on the behavioral responses of the common octopus Octopus vulgaris. In each experiment, isoflurane was equilibrated into a well-aerated seawater bath containing a single adult O. vulgaris. Using a web camera, we recorded each animal's response to touch stimuli eliciting withdrawal of the arms and siphon and observed changes in the respiratory rate and the chromatophore pattern over time (before, during, and after application of the anesthetic). We found that different animals of the same size responded with similar behavioral changes as the isoflurane concentration was gradually increased. After gradual application of 2% isoflurane for a maximum of 5 min (at which time all the responses indicated deep anesthesia), the animals recovered within 45-60 min in fresh aerated seawater. Based on previous findings in gastropods, we believe that the process of anesthesia induced by isoflurane is similar to that previously observed in Lymnaea. In this study we showed that isoflurane is a good, reversible anesthetic for O. vulgaris, and we developed a method for its use.

  6. Body Size, Growth and Life Span: Implications for the Polewards Range Shift of Octopus tetricus in South-Eastern Australia

    PubMed Central

    Ramos, Jorge E.; Pecl, Gretta T.; Moltschaniwskyj, Natalie A.; Strugnell, Jan M.; León, Rafael I.; Semmens, Jayson M.

    2014-01-01

    Understanding the response of any species to climate change can be challenging. However, in short-lived species the faster turnover of generations may facilitate the examination of responses associated with longer-term environmental change. Octopus tetricus, a commercially important species, has undergone a recent polewards range shift in the coastal waters of south-eastern Australia, thought to be associated with the southerly extension of the warm East Australian Current. At the cooler temperatures of a polewards distribution limit, growth of a species could be slower, potentially leading to a bigger body size and resulting in a slower population turnover, affecting population viability at the extreme of the distribution. Growth rates, body size, and life span of O. tetricus were examined at the leading edge of a polewards range shift in Tasmanian waters (40°S and 147°E) throughout 2011. Octopus tetricus had a relatively small body size and short lifespan of approximately 11 months that, despite cooler temperatures, would allow a high rate of population turnover and may facilitate the population increase necessary for successful establishment in the new extended area of the range. Temperature, food availability and gender appear to influence growth rate. Individuals that hatched during cooler and more productive conditions, but grew during warming conditions, exhibited faster growth rates and reached smaller body sizes than individuals that hatched into warmer waters but grew during cooling conditions. This study suggests that fast growth, small body size and associated rapid population turnover may facilitate the range shift of O. tetricus into Tasmanian waters. PMID:25090250

  7. Signature lipids and stable carbon isotope analyses of Octopus Spring hyperthermophilic communities compared with those of Aquificales representatives

    NASA Technical Reports Server (NTRS)

    Jahnke, L. L.; Eder, W.; Huber, R.; Hope, J. M.; Hinrichs, K. U.; Hayes, J. M.; Des Marais, D. J.; Cady, S. L.; Summons, R. E.

    2001-01-01

    The molecular and isotopic compositions of lipid biomarkers of cultured Aquificales genera have been used to study the community and trophic structure of the hyperthermophilic pink streamers and vent biofilm from Octopus Spring. Thermocrinis ruber, Thermocrinis sp. strain HI 11/12, Hydrogenobacter thermophilus TK-6, Aquifex pyrophilus, and Aquifex aeolicus all contained glycerol-ether phospholipids as well as acyl glycerides. The n-C(20:1) and cy-C(21) fatty acids dominated all of the Aquificales, while the alkyl glycerol ethers were mainly C(18:0). These Aquificales biomarkers were major constituents of the lipid extracts of two Octopus Spring samples, a biofilm associated with the siliceous vent walls, and the well-known pink streamer community (PSC). Both the biofilm and the PSC contained mono- and dialkyl glycerol ethers in which C(18) and C(20) alkyl groups were prevalent. Phospholipid fatty acids included both the Aquificales n-C(20:1) and cy-C(21), plus a series of iso-branched fatty acids (i-C(15:0) to i-C(21:0)), indicating an additional bacterial component. Biomass and lipids from the PSC were depleted in (13)C relative to source water CO(2) by 10.9 and 17.2 per thousand, respectively. The C(20-21) fatty acids of the PSC were less depleted than the iso-branched fatty acids, 18.4 and 22.6 per thousand, respectively. The biomass of T. ruber grown on CO(2) was depleted in (13)C by only 3.3 per thousand relative to C source. In contrast, biomass was depleted by 19.7 per thousand when formate was the C source. Independent of carbon source, T. ruber lipids were heavier than biomass (+1.3 per thousand). The depletion in the C(20-21) fatty acids from the PSC indicates that Thermocrinis biomass must be similarly depleted and too light to be explained by growth on CO(2). Accordingly, Thermocrinis in the PSC is likely to have utilized formate, presumably generated in the spring source region.

  8. Signature Lipids and Stable Carbon Isotope Analyses of Octopus Spring Hyperthermophilic Communities Compared with Those of Aquificales Representatives

    PubMed Central

    Jahnke, Linda L.; Eder, Wolfgang; Huber, Robert; Hope, Janet M.; Hinrichs, Kai-Uwe; Hayes, John M.; Des Marais, David J.; Cady, Sherry L.; Summons, Roger E.

    2001-01-01

    The molecular and isotopic compositions of lipid biomarkers of cultured Aquificales genera have been used to study the community and trophic structure of the hyperthermophilic pink streamers and vent biofilm from Octopus Spring. Thermocrinis ruber, Thermocrinis sp. strain HI 11/12, Hydrogenobacter thermophilus TK-6, Aquifex pyrophilus, and Aquifex aeolicus all contained glycerol-ether phospholipids as well as acyl glycerides. The n-C20:1 and cy-C21 fatty acids dominated all of the Aquificales, while the alkyl glycerol ethers were mainly C18:0. These Aquificales biomarkers were major constituents of the lipid extracts of two Octopus Spring samples, a biofilm associated with the siliceous vent walls, and the well-known pink streamer community (PSC). Both the biofilm and the PSC contained mono- and dialkyl glycerol ethers in which C18 and C20 alkyl groups were prevalent. Phospholipid fatty acids included both the Aquificales n-C20:1 and cy-C21, plus a series of iso-branched fatty acids (i-C15:0 to i-C21:0), indicating an additional bacterial component. Biomass and lipids from the PSC were depleted in 13C relative to source water CO2 by 10.9 and 17.2‰, respectively. The C20–21 fatty acids of the PSC were less depleted than the iso-branched fatty acids, 18.4 and 22.6‰, respectively. The biomass of T. ruber grown on CO2 was depleted in 13C by only 3.3‰ relative to C source. In contrast, biomass was depleted by 19.7‰ when formate was the C source. Independent of carbon source, T. ruber lipids were heavier than biomass (+1.3‰). The depletion in the C20–21 fatty acids from the PSC indicates that Thermocrinis biomass must be similarly depleted and too light to be explained by growth on CO2. Accordingly, Thermocrinis in the PSC is likely to have utilized formate, presumably generated in the spring source region. PMID:11679343

  9. Ontogeny of tetrodotoxin levels in blue-ringed octopuses: maternal investment and apparent independent production in offspring of Hapalochlaena lunulata.

    PubMed

    Williams, Becky L; Hanifin, Charles T; Brodie, Edmund D; Caldwell, Roy L

    2011-01-01

    Many organisms provision offspring with antipredator chemicals. Adult blue-ringed octopuses (Hapalochlaena spp.) harbor tetrodotoxin (TTX), which may be produced by symbiotic bacteria. Regardless of the ultimate source, we find that females invest TTX into offspring and offspring TTX levels are significantly correlated with female TTX levels. Because diversion of TTX to offspring begins during the earliest stages of egg formation, when females are still actively foraging and looking for mates, females may face an evolutionary tradeoff between provisioning larger stores of TTX in eggs and retaining that TTX for their own defense and offense (venom). Given that total TTX levels appear to increase during development and that female TTX levels correlate with those of offspring, investment may be an active adaptive process. Even after eggs have been laid, TTX levels continue to increase, suggesting that offspring or their symbionts begin producing TTX independently. The maternal investment of TTX in offspring of Hapalochlaena spp. represents a rare examination of chemical defenses, excepting ink, in cephalopods.

  10. Identification and Expression of Acetylcholinesterase in Octopus vulgaris Arm Development and Regeneration: a Conserved Role for ACHE?

    PubMed

    Fossati, Sara Maria; Candiani, Simona; Nödl, Marie-Therese; Maragliano, Luca; Pennuto, Maria; Domingues, Pedro; Benfenati, Fabio; Pestarino, Mario; Zullo, Letizia

    2015-08-01

    Acetylcholinesterase (ACHE) is a glycoprotein with a key role in terminating synaptic transmission in cholinergic neurons of both vertebrates and invertebrates. ACHE is also involved in the regulation of cell growth and morphogenesis during embryogenesis and regeneration acting through its non-cholinergic sites. The mollusk Octopus vulgaris provides a powerful model for investigating the mechanisms underlying tissue morphogenesis due to its high regenerative power. Here, we performed a comparative investigation of arm morphogenesis during adult arm regeneration and embryonic arm development which may provide insights on the conserved ACHE pathways. In this study, we cloned and characterized O. vulgaris ACHE, finding a single highly conserved ACHE hydrophobic variant, characterized by prototypical catalytic sites and a putative consensus region for a glycosylphosphatidylinositol (GPI)-anchor attachment at the COOH-terminus. We then show that its expression level is correlated to the stage of morphogenesis in both adult and embryonic arm. In particular, ACHE is localized in typical neuronal sites when adult-like arm morphology is established and in differentiating cell locations during the early stages of arm morphogenesis. This possibility is also supported by the presence in the ACHE sequence and model structure of both cholinergic and non-cholinergic sites. This study provides insights into ACHE conserved roles during processes of arm morphogenesis. In addition, our modeling study offers a solid basis for predicting the interaction of the ACHE domains with pharmacological blockers for in vivo investigations. We therefore suggest ACHE as a target for the regulation of tissue morphogenesis.

  11. A new species of pouched octopus, Cistopus Gray, 1849 (Cephalopoda: Octopodidae) from the southwest coast of India.

    PubMed

    Sreeja, Vijayamma; Norman, Mark D; Kumar, Appukuttannair Biju

    2015-12-16

    Octopuses of the genus Cistopus Gray, 1849 are commercially valuable catches in the cephalopod fisheries of India. The primary and unique diagnostic character of this genus is the possession of eight small mucous pouches embedded in the oral faces of the webs between the bases of each arm. Historically only a single species of Cistopus, C. indicus, had been reported from Indian waters. In reviewing the octopod fauna off the Kerala coast, we have detected three species of Cistopus, of which one is described here as a new species. Cistopus platinoidus sp. nov. is distinct from Cistopus species described to date (C. indicus, C. taiwanicus and C. chinensis) on the basis of sucker counts, the number and position of enlarged suckers in males, and presence/absence of a calamus. Our studies of catch composition of Kerala octopod fisheries indicate a higher diversity of target species than previously suspected, including a number of undescribed species. Taxonomic resolution and collation of biological and distributional data are required for effective monitoring and management of these valuable fisheries.

  12. Cryptic speciation and the circumpolarity debate: A case study on endemic Southern Ocean octopuses using the COI barcode of life

    NASA Astrophysics Data System (ADS)

    Allcock, A. Louise; Barratt, Iain; Eléaume, Marc; Linse, Katrin; Norman, Mark D.; Smith, Peter J.; Steinke, Dirk; Stevens, Darren W.; Strugnell, Jan M.

    2011-03-01

    Three hundred and fifty specimens of the endemic Southern Ocean octopus genus Pareledone, were sequenced for the barcoding gene COI. Geographic coverage comprised the South Shetland Islands, the Ross Sea, Adélie Land, George V Land, the Weddell Sea, under the site of the former Larsen B ice shelf, Prydz Bay, the South Orkney Islands and the Amundsen Sea. The greatest number of specimens was captured at the three first-mentioned localities. At least 11 species were represented in the samples and the analyses revealed cryptic species. Six species were found to have extended distributions. Circumpolarity is supported for at least one species. Evidence is presented for a barrier to gene flow to the west of the Antarctic Peninsula, with haplotypes of P. aequipapillae becoming progressively more diverse in a clockwise direction from the South Shetland Islands to the Amundsen Sea. This pattern is akin to that seen in ring species, although we suggest that comparatively warm bottom water acts as a physical barrier preventing completion of the ring.

  13. Conservative nature of oestradiol signalling pathways in the brain lobes of octopus vulgaris involved in reproduction, learning and motor coordination.

    PubMed

    De Lisa, E; Paolucci, M; Di Cosmo, A

    2012-02-01

    Oestradiol plays crucial roles in the mammalian brain by modulating reproductive behaviour, neural plasticity and pain perception. The cephalopod Octopus vulgaris is considered, along with its relatives, to be the most behaviourally advanced invertebrate, although the neurophysiological basis of its behaviours, including pain perception, remain largely unknown. In the present study, using a combination of molecular and imaging techniques, we found that oestradiol up-regulated O. vulgaris gonadotrophin-releasing hormone (Oct-GnRH) and O. vulgaris oestrogen receptor (Oct-ER) mRNA levels in the olfactory lobes; in turn, Oct-ER mRNA was regulated by NMDA in lobes involved in learning and motor coordination. Fluorescence resonance energy transfer analysis revealed that oestradiol binds Oct-ER causing conformational modifications and nuclear translocation consistent with the classical genomic mechanism of the oestrogen receptor. Moreover, oestradiol triggered a calcium influx and cyclic AMP response element binding protein phosphorylation via membrane receptors, providing evidence for a rapid nongenomic action of oestradiol in O. vulgaris. In the present study, we demonstrate, for the first time, the physiological role of oestradiol in the brain lobes of O. vulgaris involved in reproduction, learning and motor coordination.

  14. Structure and function of the carboxyl-terminal oxygen-binding domain from the subunit of Octopus dofleini hemocyanin.

    PubMed

    Miller, K I; van Holde, K E; Toumadje, A; Johnson, W C; Lamy, J

    1988-09-20

    The C-terminal domain, Od-1, of the 7-domain subunit of Octopus dofleini hemocyanin has been prepared by partial trypsinolysis followed by ion-exchange chromatography. It binds oxygen reversibly and is homogeneous in molecular weight. Its physical properties have been compared with those of the subunit. The domain molecular weight is found by sedimentation equilibrium to be 4.7 X 10(4), in excellent agreement with the result recently obtained in our laboratory from cDNA sequencing of this domain [Lang, W. H. (1988) Biochemistry (preceding paper in this issue)]. It has a sedimentation coefficient of 3.8 S. Both the molecular weight and sedimentation coefficient are consistent with the domain constituting approximately one-seventh of the Mr 3.5 X 10(5) subunit. Its amino acid composition and carbohydrate content differ significantly from that of the whole subunit, confirming the heterogeneity in domains previously established on an immunological basis. Circular dichroism predicts similar secondary structure for the domain and subunit. The domain does not self-associate in the presence of Mg2+ but does bind to the whole molecule in a ratio of approximately 1 domain/subunit. The oxygen affinity of this domain is quite low. It shows intrinsic magnesium and Bohr effects similar to those of the whole molecule but of greatly reduced magnitude. PMID:3207676

  15. Cloning and sequencing of Octopus dofleini hemocyanin cDNA: derived sequences of functional units Ode and Odf.

    PubMed

    Lang, W H; van Holde, K E

    1991-01-01

    A number of additional cDNA clones coding for portions of the very large polypeptide chain of Octopus dofleini hemocyanin were isolated and sequenced. These data reveal two very similar coding sequences, which we have denoted "A-type" and "G-type." We have obtained complete A-type sequences coding for functional units Ode and Odf; consequently a total of three such unit sequences are now known from a single subunit of one molluscan hemocyanin. This presents the opportunity to make sequence comparisons within one hemocyanin subunit. Domains within one subunit show on the average 42% identity in amino acid residues; corresponding functional units from hemocyanins of different species show degrees of identity of 53-75%. Therefore, molluscan hemocyanins already existed before the individual molluscan classes diverged in the early Cambrian. Sequence comparisons of molluscan hemocyanins with arthropodan hemocyanins and tyrosinases allow us to identify the ligands of the "Copper B" site with high probability. Possible ligands for the "Copper A" site are proposed, based on sequence comparisons between molluscan hemocyanins and tyrosinases. Besides two histidine side chains, a methionine side chain might be involved in binding of Copper A, a result not in conflict with spectroscopic studies. PMID:1898774

  16. A new species of pouched octopus, Cistopus Gray, 1849 (Cephalopoda: Octopodidae) from the southwest coast of India.

    PubMed

    Sreeja, Vijayamma; Norman, Mark D; Kumar, Appukuttannair Biju

    2015-01-01

    Octopuses of the genus Cistopus Gray, 1849 are commercially valuable catches in the cephalopod fisheries of India. The primary and unique diagnostic character of this genus is the possession of eight small mucous pouches embedded in the oral faces of the webs between the bases of each arm. Historically only a single species of Cistopus, C. indicus, had been reported from Indian waters. In reviewing the octopod fauna off the Kerala coast, we have detected three species of Cistopus, of which one is described here as a new species. Cistopus platinoidus sp. nov. is distinct from Cistopus species described to date (C. indicus, C. taiwanicus and C. chinensis) on the basis of sucker counts, the number and position of enlarged suckers in males, and presence/absence of a calamus. Our studies of catch composition of Kerala octopod fisheries indicate a higher diversity of target species than previously suspected, including a number of undescribed species. Taxonomic resolution and collation of biological and distributional data are required for effective monitoring and management of these valuable fisheries. PMID:26701522

  17. Identification and Expression of Acetylcholinesterase in Octopus vulgaris Arm Development and Regeneration: a Conserved Role for ACHE?

    PubMed

    Fossati, Sara Maria; Candiani, Simona; Nödl, Marie-Therese; Maragliano, Luca; Pennuto, Maria; Domingues, Pedro; Benfenati, Fabio; Pestarino, Mario; Zullo, Letizia

    2015-08-01

    Acetylcholinesterase (ACHE) is a glycoprotein with a key role in terminating synaptic transmission in cholinergic neurons of both vertebrates and invertebrates. ACHE is also involved in the regulation of cell growth and morphogenesis during embryogenesis and regeneration acting through its non-cholinergic sites. The mollusk Octopus vulgaris provides a powerful model for investigating the mechanisms underlying tissue morphogenesis due to its high regenerative power. Here, we performed a comparative investigation of arm morphogenesis during adult arm regeneration and embryonic arm development which may provide insights on the conserved ACHE pathways. In this study, we cloned and characterized O. vulgaris ACHE, finding a single highly conserved ACHE hydrophobic variant, characterized by prototypical catalytic sites and a putative consensus region for a glycosylphosphatidylinositol (GPI)-anchor attachment at the COOH-terminus. We then show that its expression level is correlated to the stage of morphogenesis in both adult and embryonic arm. In particular, ACHE is localized in typical neuronal sites when adult-like arm morphology is established and in differentiating cell locations during the early stages of arm morphogenesis. This possibility is also supported by the presence in the ACHE sequence and model structure of both cholinergic and non-cholinergic sites. This study provides insights into ACHE conserved roles during processes of arm morphogenesis. In addition, our modeling study offers a solid basis for predicting the interaction of the ACHE domains with pharmacological blockers for in vivo investigations. We therefore suggest ACHE as a target for the regulation of tissue morphogenesis. PMID:25112677

  18. Immunohistochemical observations of methionine-enkephalin and delta opioid receptor in the digestive system of Octopus ocellatus.

    PubMed

    Sha, Ailong; Sun, Hushan; Wang, Yiyan

    2013-02-01

    The study was designed to determine whether methionine-enkephalin (met-Enk) or delta opioid receptor was present in the digestive system of Octopus ocellatus. The results showed that they were both in the bulbus oris, esophagus, crop, stomach, gastric cecum, intestine, posterior salivary glands of O. ocellatus, one of them, met-Enk in the rectum, anterior salivary glands, digestive gland. And the distributions were extensive in the digestive system. Strong or general met-Enk immunoreactivity was observed in the inner epithelial cells of the bulbus oris, esophagus, stomach, gastric cecum, intestine, anterior salivary glands and the adventitia of the intestine and rectum, and so was the delta opioid receptor immunoreactivity in the inner epithelial cells of the bulbus oris, esophagus, and crop, however, they were weak in other parts. Combining with delta opioid receptor, met-Enk may be involved in the regulations of food intake, absorption, movement of gastrointestinal smooth muscle and secretion of digestive gland. The different densities of met-Enk and delta opioid receptor may be related to the different functions in the digestive system of O. ocellatus.

  19. Reproductive traits of sandbird octopus, Amphioctopus aegina (Gray, 1849) from Mandapam coastal waters (Palk Bay), Southeast Coast of India

    NASA Astrophysics Data System (ADS)

    Ignatius, Boby; Srinivasan, Muthukumarasamy; Balakrishnan, Srinivasan

    2011-09-01

    The sandbird octopus Amphioctopus aegina (Gray, 1849) is one of the important octopod species in trawl catches in Mandapam waters (Palk Bay). The reproductive biology of this species from these waters was studied from October 2001 to September 2002. In the majority of months(Jan-June), the sex ratio was biased towards males. The ratios of males to females increased consistently with respect to weight Total weight at first maturity were 78.78g for females and 40.8 g for males. Four maturity stags were recognized for females and two for males. Maturation and spawning occur all year round, with a peak during October and another peak during January-February. In males, no definite seasonal changes were observed in gonadosomatic index (GSI) values. In females there were two peaks in GSI values during October and January-February. For individuals of a DML range of 67-85 mm fecundity varied between 2,962-8,820 oocytes. The average relative fecundity was estimated at 68 to 83 and the average number oocytes per gram of ovary were 488 to 539.

  20. Conformation and structural changes of diblock copolymers with octopus-like micelle formation in the presence of external stimuli

    NASA Astrophysics Data System (ADS)

    Dammertz, K.; Saier, A. M.; Marti, O.; Amirkhani, M.

    2014-04-01

    External stimuli such as vapours and electric fields can be used to manipulate the formation of AB-diblock copolymers on surfaces. We study the conformational variation of PS-b-PMMA (polystyrene-block-poly(methyl methacrylate)), PS and PMMA adsorbed on mica and their response to saturated water or chloroform atmospheres. Using specimens with only partial polymer coverage, new unanticipated effects were observed. Water vapour, a non-solvent for all three polymers, was found to cause high surface mobility. In contrast, chloroform vapour (a solvent for all three polymers) proved to be less efficient. Furthermore, the influence of an additional applied electric field was investigated. A dc field oriented parallel to the sample surface induces the formation of polymer islands which assemble into wormlike chains. Moreover, PS-b-PMMA forms octopus-like micelles (OLMs) on mica. Under the external stimuli mentioned above, the wormlike formations of OLMs are able to align in the direction of the external electric field. In the absence of an electric field, the OLMs disaggregate and exhibit phase separated structures under chloroform vapour.

  1. Cloning and sequencing of Octopus dofleini hemocyanin cDNA: derived sequences of functional units Ode and Odf.

    PubMed Central

    Lang, W H; van Holde, K E

    1991-01-01

    A number of additional cDNA clones coding for portions of the very large polypeptide chain of Octopus dofleini hemocyanin were isolated and sequenced. These data reveal two very similar coding sequences, which we have denoted "A-type" and "G-type." We have obtained complete A-type sequences coding for functional units Ode and Odf; consequently a total of three such unit sequences are now known from a single subunit of one molluscan hemocyanin. This presents the opportunity to make sequence comparisons within one hemocyanin subunit. Domains within one subunit show on the average 42% identity in amino acid residues; corresponding functional units from hemocyanins of different species show degrees of identity of 53-75%. Therefore, molluscan hemocyanins already existed before the individual molluscan classes diverged in the early Cambrian. Sequence comparisons of molluscan hemocyanins with arthropodan hemocyanins and tyrosinases allow us to identify the ligands of the "Copper B" site with high probability. Possible ligands for the "Copper A" site are proposed, based on sequence comparisons between molluscan hemocyanins and tyrosinases. Besides two histidine side chains, a methionine side chain might be involved in binding of Copper A, a result not in conflict with spectroscopic studies. Images PMID:1898774

  2. Tailored Synthesis of Octopus-type Janus Nanoparticles for Synergistic Actively-Targeted and Chemo-Photothermal Therapy.

    PubMed

    Zhang, Lingyu; Chen, Yinyin; Li, Zilu; Li, Lu; Saint-Cricq, Philippe; Li, Chunxia; Lin, Jun; Wang, Chungang; Su, Zhongmin; Zink, Jeffrey I

    2016-02-01

    A facile, reproducible, and scalable method was explored to construct uniform Au@poly(acrylic acid) (PAA) Janus nanoparticles (JNPs). The as-prepared JNPs were used as templates to preferentially grow a mesoporous silica (mSiO2 ) shell and Au branches separately modified with methoxy-poly(ethylene glycol)-thiol (PEG) to improve their stability, and lactobionic acid (LA) for tumor-specific targeting. The obtained octopus-type PEG-Au-PAA/mSiO2 -LA Janus NPs (PEG-OJNP-LA) possess pH and NIR dual-responsive release properties. Moreover, DOX-loaded PEG-OJNP-LA, upon 808 nm NIR light irradiation, exhibit obviously higher toxicity at the cellular and animal levels compared with chemotherapy or photothermal therapy alone, indicating the PEG-OJNP-LA could be utilized as a multifunctional nanoplatform for in vitro and in vivo actively-targeted and chemo-photothermal cancer therapy. PMID:26732130

  3. Ontogeny of tetrodotoxin levels in blue-ringed octopuses: maternal investment and apparent independent production in offspring of Hapalochlaena lunulata.

    PubMed

    Williams, Becky L; Hanifin, Charles T; Brodie, Edmund D; Caldwell, Roy L

    2011-01-01

    Many organisms provision offspring with antipredator chemicals. Adult blue-ringed octopuses (Hapalochlaena spp.) harbor tetrodotoxin (TTX), which may be produced by symbiotic bacteria. Regardless of the ultimate source, we find that females invest TTX into offspring and offspring TTX levels are significantly correlated with female TTX levels. Because diversion of TTX to offspring begins during the earliest stages of egg formation, when females are still actively foraging and looking for mates, females may face an evolutionary tradeoff between provisioning larger stores of TTX in eggs and retaining that TTX for their own defense and offense (venom). Given that total TTX levels appear to increase during development and that female TTX levels correlate with those of offspring, investment may be an active adaptive process. Even after eggs have been laid, TTX levels continue to increase, suggesting that offspring or their symbionts begin producing TTX independently. The maternal investment of TTX in offspring of Hapalochlaena spp. represents a rare examination of chemical defenses, excepting ink, in cephalopods. PMID:21165679

  4. Puptrak 1.0--a new semiautomated system for pupillometry with the Octopus perimeter: a preliminary report.

    PubMed

    Fankhauser, F; Flammer, J

    1989-11-01

    A provisional, semiautomated version of a system for automated testing of the afferent pupillary reflex with perimetric methods under controlled conditions is described. The target projected onto the perimeter cupola is used as the stimulus for triggering the pupillary response. In a modification to the Octopus 201, the pupil is illuminated by two IR LED diodes, while the pupillary responses are recorded by the onboard IR sensitive TV camera built into the perimetric unit. Measurements of the pupillary area as a function of time and stimulus luminance have been performed and have resulted in consistent results. Here, one perimetric program, working with stimuli above the threshold for the afferent pupillary light reflex is described. The present setup works with system-specific software and standard hardware, the central data processing unit being a desk-top computer (IBM PC AT-03). The mating of an automated pupillary measuring unit to an automated perimeter may open the door for a more widespread evaluation of the value and the clinical application range of pupillary perimetry and may be of interest in other areas of visual and clinical psychophysics. The shortcomings of the present system, in particular insufficient temporal resolution and lack of full automation, are being removed at the present time.

  5. First descriptions of dicyemid mesozoans (Dicyemida: Dicyemidae) from Australian octopus (Octopodidae) and cuttlefish (Sepiidae), including a new record of Dicyemennea in Australian waters.

    PubMed

    Catalano, Sarah R

    2013-09-01

    Three new species of dicyemid mesozoans are described for the first time from Australian octopus and cuttlefish species. Dicyemennea floscephalum sp. n. is described from Octopus berrima Stranks et Norman (southern keeled octopus) collected from Spencer Gulf and Gulf St. Vincent, South Australia, Australia and represents the first description of a species of Dicyemennea Whitman, 1883 from Australian waters. Dicyema papuceum sp. n. and D. furuyi sp. n. are described from Sepia papuensis Hoyle (Papuan cuttlefish) collected from Shark Bay, Western Australia, Australia. Dicyemennea floscephalum sp. n. is a medium to large species that reaches approximately 4.9 mm in length. The vermiform stages are characterised by having 23-28 peripheral cells, and a disc-shaped, flower-like calotte in larger individuals. An anterior abortive axial cell is absent in vermiform embryos and verruciform cells were not observed in nematogens and rhombogens. Infusoriform embryos comprise 37 cells; one nucleus is present in each urn cell. Dicyema papuceum sp. n. is a small species that reaches approximately 1.1 mm in length. The vermiform stages are characterised by having 30-33 peripheral cells and a relatively small, cap-shaped calotte. An anterior abortive axial cell is absent in vermiform embryos and verruciform cells were occasionally observed in nematogens. Infusoriform embryos comprise 37 cells; two nuclei are present in each urn cell. Dicyema furuyi sp. n. is a large species that reaches approximately 5.3 mm in length. The vermiform stages are characterised by having 22-24 peripheral cells and an elongate calotte. An anterior abortive axial cell is absent in vermiform embryos and verruciform cells were not observed in nematogens and rhombogens. Infusoriform embryos comprise 37 cells; one nucleus is present in each urn cell. Three secondary nematogens were also observed in the right renal appendages of two host individuals, confirming the occurrence of this form. PMID:24261132

  6. First descriptions of dicyemid mesozoans (Dicyemida: Dicyemidae) from Australian octopus (Octopodidae) and cuttlefish (Sepiidae), including a new record of Dicyemennea in Australian waters.

    PubMed

    Catalano, Sarah R

    2013-09-01

    Three new species of dicyemid mesozoans are described for the first time from Australian octopus and cuttlefish species. Dicyemennea floscephalum sp. n. is described from Octopus berrima Stranks et Norman (southern keeled octopus) collected from Spencer Gulf and Gulf St. Vincent, South Australia, Australia and represents the first description of a species of Dicyemennea Whitman, 1883 from Australian waters. Dicyema papuceum sp. n. and D. furuyi sp. n. are described from Sepia papuensis Hoyle (Papuan cuttlefish) collected from Shark Bay, Western Australia, Australia. Dicyemennea floscephalum sp. n. is a medium to large species that reaches approximately 4.9 mm in length. The vermiform stages are characterised by having 23-28 peripheral cells, and a disc-shaped, flower-like calotte in larger individuals. An anterior abortive axial cell is absent in vermiform embryos and verruciform cells were not observed in nematogens and rhombogens. Infusoriform embryos comprise 37 cells; one nucleus is present in each urn cell. Dicyema papuceum sp. n. is a small species that reaches approximately 1.1 mm in length. The vermiform stages are characterised by having 30-33 peripheral cells and a relatively small, cap-shaped calotte. An anterior abortive axial cell is absent in vermiform embryos and verruciform cells were occasionally observed in nematogens. Infusoriform embryos comprise 37 cells; two nuclei are present in each urn cell. Dicyema furuyi sp. n. is a large species that reaches approximately 5.3 mm in length. The vermiform stages are characterised by having 22-24 peripheral cells and an elongate calotte. An anterior abortive axial cell is absent in vermiform embryos and verruciform cells were not observed in nematogens and rhombogens. Infusoriform embryos comprise 37 cells; one nucleus is present in each urn cell. Three secondary nematogens were also observed in the right renal appendages of two host individuals, confirming the occurrence of this form.

  7. Serotonin is a facilitatory neuromodulator of synaptic transmission and "reinforces" long-term potentiation induction in the vertical lobe of Octopus vulgaris.

    PubMed

    Shomrat, T; Feinstein, N; Klein, M; Hochner, B

    2010-08-11

    The modern cephalopod mollusks (coleoids) are considered the most behaviorally advanced invertebrate, yet little is known about the neurophysiological basis of their behaviors. Previous work suggested that the vertical lobe (VL) of cephalopods is a crucial site for the learning and memory components of these behaviors. We are therefore studying the neurophysiology of the VL in Octopus vulgaris and have discovered a robust activity-dependent long-term potentiation (LTP) of the synaptic input to the VL. Moreover, we have shown that the VL and its LTP are involved in behavioral long-term memory acquisition. To advance our understanding of the VL as a learning neural network we explore the possible involvement of neuromodulation in VL function. Here we examine whether the well studied serotonergic modulation in simple models of learning in gastropods mollusks is conserved in the octopus VL. We demonstrate histochemically that the VL is innervated by afferent terminals containing 5-HT immunoreactivity (5-HT-IR). Physiologically, 5-HT has a robust facilitatory effect on synaptic transmission and activity-dependent LTP induction. These results suggest that serotonergic neuromodulation is a part of a reinforcing/reward signaling system conserved in both simple and complex learning systems of mollusks. However, there are notable functional differences. First, the effective concentration of 5-HT in the VL is rather high (100 microM); secondly, only neuropilar regions but not cell bodies in the VL are innervated by terminals containing 5-HT-IR. Thirdly, repetitive or long exposures to 5-HT do not lead to a clear long-term facilitation. We propose that in the octopus VL, while the basic facilitatory properties of molluscan 5-HT system are conserved, the system has adapted to convey signals from other brain areas to reinforce the activity-dependent associations at specific sites in the large connections matrix in the VL.

  8. Sphero-echinocytosis of human red blood cells caused by snake, red-back spider, bee and blue-ringed octopus venoms and its inhibition by snake sera.

    PubMed

    Flachsenberger, W; Leigh, C M; Mirtschin, P J

    1995-06-01

    It was found that bee (Apis mellifera) venom, red-back spider (Latrodectus mactans) venom, blue-ringed octopus (Hapalochlaena maculosa) venom, ten different snake venoms, phospholipase A2 and four snake toxins caused sphero-echinocytosis of human red blood cells at 200 ng/ml. Most venoms and toxins lost the ability to deform human red blood cells when their components of less than mol. wt 10,000 were applied. In a number of cases the sphero-echinocytotic effect was also inhibited by blood sera of Notechis scutatus and Pseudonaja textilis. PMID:7676470

  9. Involvement of a Serpin serine protease inhibitor (OoSerpin) from mollusc Octopus ocellatus in antibacterial response.

    PubMed

    Wei, Xiumei; Xu, Jie; Yang, Jianmin; Liu, Xiangquan; Zhang, Ranran; Wang, Weijun; Yang, Jialong

    2015-01-01

    Serpin is an important member of serine protease inhibitors (SPIs), which is capable of regulating proteolytic events and involving in a variety of physiological processes. In present study, a Serpin homolog was identified from Octopus ocellatus (designated as OoSerpin). Full-length cDNA of OoSerpin was of 1735 bp, containing a 5' untranslated region of 214 bp, a 3' UTR of 282 bp, and an open reading frame of 1239 bp. The open reading frame encoded a polypeptide of 412 amino acids which has a predicted molecular weight of 46.5 kDa and an isoelectric point of 8.52. The OoSerpin protein shares 37% sequence identity with other Serpins from Mus musculus (NP_941373) and Ixodes scapularis (XP_002407493). The existence of a conserved SERPIN domain strongly suggested that OoSerpin was a member of the Serpin subfamily. Expression patterns of OoSerpin, both in tissues and towards bacterial stimulation, were then characterized. The mRNA of OoSerpin was constitutively expressed at different levels in all tested tissues of untreated O. ocellatus, including mantle (lowest), muscle, renal sac, gill, hemocyte, gonad, systemic heart, and hepatopancreas (highest). The transcriptional level of OoSerpin was significantly up-regulated (P<0.01) in O. ocellatus upon bacterial challenges with Vibrio anguillarum and Micrococcus luteus, indicating its involvement in the antibacterial immune response. Furthermore, rOoSerpin, the recombinant protein of OoSerpin, exhibited strong abilities to inhibit proteinase activities of trypsin and chymotrypsin as well as the growth of Escherichia coli. Our results demonstrate that OoSerpin is a potential antibacterial factor involved in the immune response of O. ocellatus against bacterial infection.

  10. Involvement of a Serpin serine protease inhibitor (OoSerpin) from mollusc Octopus ocellatus in antibacterial response.

    PubMed

    Wei, Xiumei; Xu, Jie; Yang, Jianmin; Liu, Xiangquan; Zhang, Ranran; Wang, Weijun; Yang, Jialong

    2015-01-01

    Serpin is an important member of serine protease inhibitors (SPIs), which is capable of regulating proteolytic events and involving in a variety of physiological processes. In present study, a Serpin homolog was identified from Octopus ocellatus (designated as OoSerpin). Full-length cDNA of OoSerpin was of 1735 bp, containing a 5' untranslated region of 214 bp, a 3' UTR of 282 bp, and an open reading frame of 1239 bp. The open reading frame encoded a polypeptide of 412 amino acids which has a predicted molecular weight of 46.5 kDa and an isoelectric point of 8.52. The OoSerpin protein shares 37% sequence identity with other Serpins from Mus musculus (NP_941373) and Ixodes scapularis (XP_002407493). The existence of a conserved SERPIN domain strongly suggested that OoSerpin was a member of the Serpin subfamily. Expression patterns of OoSerpin, both in tissues and towards bacterial stimulation, were then characterized. The mRNA of OoSerpin was constitutively expressed at different levels in all tested tissues of untreated O. ocellatus, including mantle (lowest), muscle, renal sac, gill, hemocyte, gonad, systemic heart, and hepatopancreas (highest). The transcriptional level of OoSerpin was significantly up-regulated (P<0.01) in O. ocellatus upon bacterial challenges with Vibrio anguillarum and Micrococcus luteus, indicating its involvement in the antibacterial immune response. Furthermore, rOoSerpin, the recombinant protein of OoSerpin, exhibited strong abilities to inhibit proteinase activities of trypsin and chymotrypsin as well as the growth of Escherichia coli. Our results demonstrate that OoSerpin is a potential antibacterial factor involved in the immune response of O. ocellatus against bacterial infection. PMID:25449372

  11. Normal Values for the Full Visual Field, Corrected for Age- and Reaction Time, Using Semiautomated Kinetic Testing on the Octopus 900 Perimeter

    PubMed Central

    Grobbel, Julia; Dietzsch, Janko; Johnson, Chris A.; Vonthein, Reinhard; Stingl, Katarina; Weleber, Richard G.; Schiefer, Ulrich

    2016-01-01

    Purpose To determine normal values of the visual field (VF), corrected for age and reaction time (RT) for semiautomated kinetic perimetry (SKP) on the Octopus 900 perimeter, create a model describing the age-dependency of these values, and assess test–retest reliability for each isopter. Methods Eighty-six eyes of 86 ophthalmologically healthy subjects (age 11–79 years, 34 males, 52 females) underwent full-field kinetic perimetry with the Octopus 900 instrument. Stimulus size, luminance, velocity, meridional angle, subject age, and their interactions, were used to create a smooth multiple regression mathematical model (V/4e, III/4e, I/4e, I/3e, I/2e, I/1e, and I/1a isopters). Fourteen subjects (2 from each of 7 age groups) were evaluated on three separate sessions to assess test–retest reliability of the isopters. Reaction time (RT) was tested by presenting 12 designated RT-vectors between 10° and 20° within the seeing areas for the III/4e isopter (stimulus velocity, 3°/second). Four RT- vectors were presented at the nasal (0° or 180°), superotemporal (45°), and inferior (270°) meridians. Results The model fit was excellent (r2 = 0.94). The test–retest variability was less than 5°, and the median decrease in this deviation attributed to aging, per decade, for all age groups and for all stimulus sizes was 0.8°. No significant learning effect was observed for any age group or isopter. Conclusion Age-corrected and RT-corrected normative threshold values for full-field kinetic perimetry can be adequately described by a smooth multiple linear regression mathematical model. Translational Relevance A description of the entire kinetic VF is useful for assessing a full characterization of VF sensitivity, determining function losses associated with ocular and neurologic diseases, and for providing a more comprehensive analysis of structure–function relationships. PMID:26966641

  12. Analysis of the 3’ untranslated regions of α-tubulin and S-crystallin mRNA and the identification of CPEB in dark- and light-adapted octopus retinas

    PubMed Central

    Kelly, Shannan; Yamamoto, Hideki

    2008-01-01

    Purpose We previously reported the differential expression and translation of mRNA and protein in dark- and light-adapted octopus retinas, which may result from cytoplasmic polyadenylation element (CPE)–dependent mRNA masking and unmasking. Here we investigate the presence of CPEs in α-tubulin and S-crystallin mRNA and report the identification of cytoplasmic polyadenylation element binding protein (CPEB) in light- and dark-adapted octopus retinas. Methods 3’-RACE and sequencing were used to isolate and analyze the 3’-UTRs of α-tubulin and S-crystallin mRNA. Total retinal protein isolated from light- and dark-adapted octopus retinas was subjected to western blot analysis followed by CPEB antibody detection, PEP-171 inhibition of CPEB, and dephosphorylation of CPEB. Results The following CPE-like sequence was detected in the 3’-UTR of isolated long S-crystallin mRNA variants: UUUAACA. No CPE or CPE-like sequences were detected in the 3’-UTRs of α-tubulin mRNA or of the short S-crystallin mRNA variants. Western blot analysis detected CPEB as two putative bands migrating between 60-80 kDa, while a third band migrated below 30 kDa in dark- and light-adapted retinas. Conclusions The detection of CPEB and the identification of the putative CPE-like sequences in the S-crystallin 3’-UTR suggest that CPEB may be involved in the activation of masked S-crystallin mRNA, but not in the regulation of α-tubulin mRNA, resulting in increased S-crystallin protein synthesis in dark-adapted octopus retinas. PMID:18682811

  13. Thermal biology of prey (Melongena corona bispinosa, Strombus pugilis, Callinectes similis, Libinia dubia) and predators (Ocyurus chrysurus, Centropomus undecimalis) of Octopus maya from the Yucatan Peninsula.

    PubMed

    Noyola Regil, Javier; Mascaro, Maite; Díaz, Fernando; Denisse Re, Ana; Sánchez-Zamora, Adolfo; Caamal-Monsreal, Claudia; Rosas, Carlos

    2015-10-01

    On the Yucatan Peninsula there is an upwelling which allows access to a body of cold water that controls temperature in this area. This modulates the ecology and distribution of organisms that inhabit the continental shelf. The objective of this study was to determine the effect of different acclimation temperatures on the thermal biology of prey as mollusc, crustacean (Melongena corona bispinosa, Strombus pugilis, Callinectes similis, Libinia dubia) and predators as fish (Ocyurus chrysurus, Centropomus undecimalis) of Octopus maya. Octopus prey preferred temperatures between 23.5°C and 26.0°C, while predators preferred temperatures 26.4-28.5°C. The species with largest thermal windows were M. corona bispinosa (328.8°C(2)), C. similis (322.8°C(2)), L. dubia (319.2°C(2)), C. undecimalis (288.6°C(2)), O. chrysurus (237.5°C(2)), while the smallest thermal window was for S. pugilis (202.0°C(2)). The acclimation response ratios (ARR) estimated for prey ranged from 0.24-0.55 in animals exposed to CTMax and 0.21-0.65 in those exposed to CTMin. Amongst predators, ARR ranged from 0.30 to 0.60 and 0.41 to 0.53 for animals exposed to CTMax and CTMin, respectively. Correlating the optimal temperature limits of prey and predators with surface temperatures on the continental shelf and those 4m deep showed that the main prey, Callinectes similis and L. dubia, shared a thermal niche and that an increase in temperature could force these species to migrate to other sites to find optimal temperatures for their physiological functions. As a consequence the continental shelf community would undergo a structural change. Predators were found to be near their optimal temperatures in surface temperatures on the continental shelf. We conclude that they would remain in the area in a warming scenario. The size of the thermal window was related to the type of ecosystem inhabited by these species. These ARR intervals allowed us to categorize the species as temperate or tropical

  14. Thermal biology of prey (Melongena corona bispinosa, Strombus pugilis, Callinectes similis, Libinia dubia) and predators (Ocyurus chrysurus, Centropomus undecimalis) of Octopus maya from the Yucatan Peninsula.

    PubMed

    Noyola Regil, Javier; Mascaro, Maite; Díaz, Fernando; Denisse Re, Ana; Sánchez-Zamora, Adolfo; Caamal-Monsreal, Claudia; Rosas, Carlos

    2015-10-01

    On the Yucatan Peninsula there is an upwelling which allows access to a body of cold water that controls temperature in this area. This modulates the ecology and distribution of organisms that inhabit the continental shelf. The objective of this study was to determine the effect of different acclimation temperatures on the thermal biology of prey as mollusc, crustacean (Melongena corona bispinosa, Strombus pugilis, Callinectes similis, Libinia dubia) and predators as fish (Ocyurus chrysurus, Centropomus undecimalis) of Octopus maya. Octopus prey preferred temperatures between 23.5°C and 26.0°C, while predators preferred temperatures 26.4-28.5°C. The species with largest thermal windows were M. corona bispinosa (328.8°C(2)), C. similis (322.8°C(2)), L. dubia (319.2°C(2)), C. undecimalis (288.6°C(2)), O. chrysurus (237.5°C(2)), while the smallest thermal window was for S. pugilis (202.0°C(2)). The acclimation response ratios (ARR) estimated for prey ranged from 0.24-0.55 in animals exposed to CTMax and 0.21-0.65 in those exposed to CTMin. Amongst predators, ARR ranged from 0.30 to 0.60 and 0.41 to 0.53 for animals exposed to CTMax and CTMin, respectively. Correlating the optimal temperature limits of prey and predators with surface temperatures on the continental shelf and those 4m deep showed that the main prey, Callinectes similis and L. dubia, shared a thermal niche and that an increase in temperature could force these species to migrate to other sites to find optimal temperatures for their physiological functions. As a consequence the continental shelf community would undergo a structural change. Predators were found to be near their optimal temperatures in surface temperatures on the continental shelf. We conclude that they would remain in the area in a warming scenario. The size of the thermal window was related to the type of ecosystem inhabited by these species. These ARR intervals allowed us to categorize the species as temperate or tropical

  15. Genetic differentiation of octopuses from different habitats near the Korean Peninsula and eastern China based on analysis of the mDNA cytochrome C oxidase 1 gene.

    PubMed

    Kang, J-H; Park, J-Y; Choi, T-J

    2012-11-21

    Distributed along the coastal waters of Korea and China, Octopus minor is found in various habitats, including the mud flats in the southern and western coasts of the Korean Peninsula and the rocky areas around Jeju Island; however, the genetic relationships among the different populations are unknown and have not been studied. We compared 630-nucleotide sequences of the CO1 gene from O. minor specimens collected from five regions around the Korean Peninsula and three regions from eastern China in order to determine population structure and genetic relationships. Based on the sequences at 12 polymorphic sites in this region, 11 haplotypes were identified from 85 specimens. Individuals from Jeju Island had unique haplotypes, including two haplotypes not found in the other populations. Nucleotide and haplotype diversity for all populations ranged from 0.03-0.37 and 0.20-0.64, respectively. Pairwise F(ST) values indicated significant genetic differences in populations from Korea and China. An UPGMA dendrogram showed separation of the eight populations into three clusters; one included only the Jeju population, another included the rest of the Korean populations and some from Dalian, China; a third cluster consisted of two other populations from China. We conclude that there are discrete genetic differences in O. minor from the different habitats, suggesting that the populations should be considered as management units in the ongoing recovery program.

  16. Genetic differentiation of octopuses from different habitats near the Korean Peninsula and eastern China based on analysis of the mDNA cytochrome C oxidase 1 gene.

    PubMed

    Kang, J-H; Park, J-Y; Choi, T-J

    2012-01-01

    Distributed along the coastal waters of Korea and China, Octopus minor is found in various habitats, including the mud flats in the southern and western coasts of the Korean Peninsula and the rocky areas around Jeju Island; however, the genetic relationships among the different populations are unknown and have not been studied. We compared 630-nucleotide sequences of the CO1 gene from O. minor specimens collected from five regions around the Korean Peninsula and three regions from eastern China in order to determine population structure and genetic relationships. Based on the sequences at 12 polymorphic sites in this region, 11 haplotypes were identified from 85 specimens. Individuals from Jeju Island had unique haplotypes, including two haplotypes not found in the other populations. Nucleotide and haplotype diversity for all populations ranged from 0.03-0.37 and 0.20-0.64, respectively. Pairwise F(ST) values indicated significant genetic differences in populations from Korea and China. An UPGMA dendrogram showed separation of the eight populations into three clusters; one included only the Jeju population, another included the rest of the Korean populations and some from Dalian, China; a third cluster consisted of two other populations from China. We conclude that there are discrete genetic differences in O. minor from the different habitats, suggesting that the populations should be considered as management units in the ongoing recovery program. PMID:23212336

  17. Surface orientation affects the direction of cone growth by Leptolyngbya sp. strain C1, a likely architect of coniform structures Octopus Spring (Yellowstone National Park).

    PubMed

    Reyes, Kristina; Gonzalez, Nicolas I; Stewart, Joshua; Ospino, Frank; Nguyen, Dickie; Cho, David T; Ghahremani, Nahal; Spear, John R; Johnson, Hope A

    2013-02-01

    Laminated, microbially produced stromatolites within the rock record provide some of the earliest evidence for life on Earth. The chemical, physical, and biological factors that lead to the initiation of these organosedimentary structures and shape their morphology are unclear. Modern coniform structures with morphological features similar to stromatolites are found on the surface of cyanobacterial/microbial mats. They display a vertical element of growth, can have lamination, can be lithified, and observably grow with time. To begin to understand the microbial processes and interactions required for cone formation, we determined the phylogenetic composition of the microbial community of a coniform structure from a cyanobacterial mat at Octopus Spring, Yellowstone National Park, and reconstituted coniform structures in vitro. The 16S rRNA clone library from the coniform structure was dominated by Leptolyngbya sp. Other cyanobacteria and heterotrophic bacteria were present in much lower abundance. The same Leptolyngbya sp. identified in the clone library was also enriched in the laboratory and could produce cones in vitro. When coniform structures were cultivated in the laboratory, the initial incubation conditions were found to influence coniform morphology. In addition, both the angle of illumination and the orientation of the surface affected the angle of cone formation demonstrating how external factors can influence coniform, and likely, stromatolite morphology.

  18. The Octopus, the Squid and the Tortoise

    ERIC Educational Resources Information Center

    Caruth, Gail D.; Caruth, Donald L.

    2013-01-01

    What is the role of the Doctor of Philosophy (PhD) today? This is not a new question. In 1903, William James questioned the value of the degree as an indicator of teaching ability. Unfortunately, the issue James raised has never been resolved. Move forward in time to 1990. Theodore Ziolkowski essentially agreed with James, but raised additional…

  19. We'll Paint the Octopus Red.

    ERIC Educational Resources Information Center

    Stuve-Bodeen, Stephanie

    This children's book tells the story of a little girl who has a new baby brother with Down syndrome. Her contemplation of the advantages and disadvantages of having a sibling is highlighted. When she finds out the baby has Down syndrome, her initial reaction is that the baby won't be able to do all the wonderful things she has thought they would…

  20. The Testing Octopus: A Tentacle for Curriculum-or-How Do You Dance with an Octopus?

    ERIC Educational Resources Information Center

    Pechman, Ellen M.; Gonzales, Maria Luisa

    This paper examines long-range problems caused by test-controlled schooling. It looks at the demands of both curricular and accountability uses of tests from the point of view of the urban school district's testing office. On the basis of interviews with 12 New Orleans teachers and the experiences of the authors in working in two large city…

  1. The Onomastic Octopus. Museum Data Bank Research Report No. 3.

    ERIC Educational Resources Information Center

    Chenhall, Robert G.

    Activities and information needs in museums and a project undertaken by the Margaret Woodbury Strong Museum to develop systematic solutions to problems in cataloging museum collections are described. Museum activities are grouped in three categories: (1) initial--acquisition, accession, registration, identification, and restoration; (2)…

  2. Storage in the LLNL Octopus network: an overview and reflections

    SciTech Connect

    Coleman, S.; Watson, R.

    1984-02-28

    The paper reviews the environment and characteristics of the central storage system at the Lawrence Livermore National Laboratory Computation Center. It then discusses some lessons learned from the successes and problems during 15 years of experience with this system and finally indicates some future directions.

  3. Flexible Octopus-Shaped Hydrogel Particles for Specific Cell Capture.

    PubMed

    Chen, Lynna; An, Harry Z; Haghgooie, Ramin; Shank, Aaron T; Martel, Joseph M; Toner, Mehmet; Doyle, Patrick S

    2016-04-01

    Multiarm hydrogel microparticles with varying geometry are fabricated to specifically capture cells expressing epithelial cell adhesion molecule. Results show that particle shape influences cell-capture efficiency due to differences in surface area, hydrodynamic effects, and steric constraints. These findings can lead to improved particle design for cell separation and diagnostic applications. PMID:26929053

  4. "Do octopuses have a brain?" Knowledge, perceptions and attitudes towards neuroscience at school.

    PubMed

    Sperduti, Alessandra; Crivellaro, Federica; Rossi, Paola Francesca; Bondioli, Luca

    2012-01-01

    The present study contributes to the question of school literacy about the brain, with an original survey conducted on Italian students from the 3(rd) to 10(th) grades (n=508). The main goal was to test student's knowledge, attitudes, and interests about neuroscience, to assess needs, prospects, and difficulties in teaching about the brain from elementary to high school. A written questionnaire, maintaining anonymity, asked 12 close-ended multiple choice questions on topics related to human and animal brains, plus one facultative open-ended question about interests and curiosities on brain topics. The results show that respondents have a fragmentary level of basic knowledge about the brain, with aspects related to brain functions and consciousness the most challenging. As expected, degrees of performance improve with school level; elementary school students answered correctly an average number of 5.3 questions, middle school 6.5, and high school 7.4. Overall, students show great interest in the brain, as shown by the large number of questions gathered through the open-ended question (n=384). Other topics are addressed, mostly related to brain structure/functions and the role of the brain in the everyday life. The survey indicates the need of more thorough school programs on this subject, reinforced by interdisciplinary teaching where comparative anatomy and evolutionary aspects of brain development are covered.

  5. Profiling Community College Journals: An Exercise in Putting Shoes on an Octopus?

    ERIC Educational Resources Information Center

    Lumsden, D. Barry; Singleton-Jackson, Jill

    2000-01-01

    Identifies (1) which community college journals have gone out of business since 1984; (2) which new journals have been launched since 1984; and (3) the current names of journals that, since 1984, have changed their names. Provides contact information for eighteen journals still in business. (PGS)

  6. "The Teacher Is an Octopus": Uncovering Preservice English Language Teachers' Prior Beliefs through Metaphor Analysis

    ERIC Educational Resources Information Center

    Farrell, Thomas S. C.

    2006-01-01

    Preservice teachers come to any teacher education course with prior experiences, knowledge and beliefs about learning and teaching. Additionally, the belief systems of preservice teachers often serve as a lens through which they view the content of the teacher education program. Consequently, it is essential that teacher educators take these prior…

  7. Male-male and male-female aggression may influence mating associations in wild octopuses (Abdopus aculeatus).

    PubMed

    Huffard, Christine L; Caldwell, Roy L; Boneka, Farnis

    2010-02-01

    Abdopus aculeatus engages in frequent aggression and copulation, exhibits male mate-choice, and employs multiple mating tactics. Here we draw upon established hypotheses to compare male-male aggression (MMA) and male-female aggression (MFA), as they relate to their mating behavior in the wild. When contesting for females, males appear to balance mate preference (resource value) with perceived chances of winning contests (resource holding potential). Although males spent more time mating with and contesting for large "Adjacent Guarded" females (those occupying a den within arm's reach of a large "Adjacent Guarding" male), they exhibited higher rates of aggression over nonadjacent "Temporarily Guarded" females that may be more accessible. The major determinant of male-male aggressive success was size, and this factor may dictate the expression of conditional mating tactics in males. "Adjacent Guarding" males were the largest and most aggressively successful males, earning the most time copulating with females. They are considered to have the highest resource holding potential (RHP) in MMA. By contrast, in MFA, some larger individuals fled from smaller individuals, indicating that RHP appears to be a function of both size and sex in intersexual aggression. This result suggests variation in aggressiveness, or potential for severe injury-even sexual cannibalism during MFA. Male-female aggression may also be influenced by the sexual nonreceptivity of some individuals, or attempts by both sexes to increase foraging behavior by delaying mate-guarding activity.

  8. Structure formation of lipid membranes: Membrane self-assembly and vesicle opening-up to octopus-like micelles

    NASA Astrophysics Data System (ADS)

    Noguchi, Hiroshi

    2013-02-01

    We briefly review our recent studies on self-assembly and vesicle rupture of lipid membranes using coarse-grained molecular simulations. For single component membranes, lipid molecules self-assemble from random gas states to vesicles via disk-shaped clusters. Clusters aggregate into larger clusters, and subsequently the large disks close into vesicles. The size of vesicles are determined by kinetics than by thermodynamics. When a vesicle composed of lipid and detergent types of molecules is ruptured, a disk-shaped micelle called bicelle can be formed. When both surfactants have negligibly low critical micelle concentration, it is found that bicelles connected with worm-like micelles are also formed depending on the surfactant ratio and spontaneous curvature of the membrane monolayer.

  9. “Do Octopuses Have a Brain?” Knowledge, Perceptions and Attitudes towards Neuroscience at School

    PubMed Central

    Sperduti, Alessandra; Crivellaro, Federica; Rossi, Paola Francesca; Bondioli, Luca

    2012-01-01

    The present study contributes to the question of school literacy about the brain, with an original survey conducted on Italian students from the 3rd to 10th grades (n = 508). The main goal was to test student's knowledge, attitudes, and interests about neuroscience, to assess needs, prospects, and difficulties in teaching about the brain from elementary to high school. A written questionnaire, maintaining anonymity, asked 12 close-ended multiple choice questions on topics related to human and animal brains, plus one facultative open-ended question about interests and curiosities on brain topics. The results show that respondents have a fragmentary level of basic knowledge about the brain, with aspects related to brain functions and consciousness the most challenging. As expected, degrees of performance improve with school level; elementary school students answered correctly an average number of 5.3 questions, middle school 6.5, and high school 7.4. Overall, students show great interest in the brain, as shown by the large number of questions gathered through the open-ended question (n = 384). Other topics are addressed, mostly related to brain structure/functions and the role of the brain in the everyday life. The survey indicates the need of more thorough school programs on this subject, reinforced by interdisciplinary teaching where comparative anatomy and evolutionary aspects of brain development are covered. PMID:23082231

  10. Molecular phylogeny and evolution of the proteins encoded by coleoid (cuttlefish, octopus, and squid) posterior venom glands.

    PubMed

    Ruder, Tim; Sunagar, Kartik; Undheim, Eivind A B; Ali, Syed A; Wai, Tak-Cheung; Low, Dolyce H W; Jackson, Timothy N W; King, Glenn F; Antunes, Agostinho; Fry, Bryan G

    2013-04-01

    In this study, we report for the first time a detailed evaluation of the phylogenetic history and molecular evolution of the major coleoid toxins: CAP, carboxypeptidase, chitinase, metalloprotease GON-domain, hyaluronidase, pacifastin, PLA2, SE-cephalotoxin and serine proteases, with the carboxypeptidase and GON-domain documented for the first time in the coleoid venom arsenal. We show that although a majority of sites in these coleoid venom-encoding genes have evolved under the regime of negative selection, a very small proportion of sites are influenced by the transient selection pressures. Moreover, nearly 70 % of these episodically adapted sites are confined to the molecular surface, highlighting the importance of variation of the toxin surface chemistry. Coleoid venoms were revealed to be as complex as other venoms that have traditionally been the recipient of the bulk of research efforts. The presence of multiple peptide/protein types in coleoids similar to those present in other animal venoms identifies a convergent strategy, revealing new information as to what characteristics make a peptide/protein type amenable for recruitment into chemical arsenals. Coleoid venoms have significant potential not only for understanding fundamental aspects of venom evolution but also as an untapped source of novel toxins for use in drug design and discovery.

  11. First record of three species of octopodidae and gonatidae, cephalopods in the East/Japan Sea.

    PubMed

    Kim, Yeonghye; Lee, Dong Woo; Hong, Byung Kyu; Chun, Young Yull

    2008-07-01

    Three species of the unrecorded octopus and squids, Octopus megalops, Berryteuthis magister and Gonatopsis makko were collected for the first time from the East/Japan Sea in June, 2005. New Korean names proposed for these three species are "Big-eye octopus, Mako gonate squid, Schoolmater gonate squid" for the O. megalops, B. magister and G. makko, respectively. We report detailed taxonomic descriptions of these species.

  12. 78 FR 69591 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Halibut and Crab Prohibited...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-20

    ... BSAI (78 FR 13813, March 1, 2013) are revised as follows in Tables 10, 12, and 14: Table 10--Final 2013... PSC monitoring includes skates, sculpins, sharks, squids, and octopuses. Note: Seasonal or...

  13. 77 FR 19146 - Fisheries of the Economic Exclusive Zone Off Alaska; Shallow-Water Species Fishery by Vessels...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-30

    ... of the GOA (77 FR 15194, March 14, 2012), for the period 1200 hrs, A.l.t., January 20, 2012, through..., octopuses, and sculpins. This prohibition does not apply to fishing for pollock by vessels using...

  14. 76 FR 17034 - Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands; Final 2011...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-28

    ... Register on Tuesday, March 1, 2011 (76 FR 11139). Tables providing information on 2011 and 2012 Directed... 43 Octopuses 128 128 Sculpins 4,420 4,420 Hook-and-line and pot ICA Pacific cod..... 500 500...

  15. 77 FR 54837 - Fisheries of the Economic Exclusive Zone Off Alaska; Shallow-Water Species Fishery by Vessels...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-06

    ... of the GOA (77 FR 15194, March 14, 2012), for the period 1200 hrs, A.l.t., September 1, 2012, through..., octopuses, and sculpins. This prohibition does not apply to fishing for pollock by vessels using...

  16. 78 FR 69649 - North Pacific Fishery Management Council; Public Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-20

    ...- Stevens Act section 302(g)(1)(e), and the National Standard 2 guidelines (78 FR 43066). The peer review...: Discussion paper on Eastern Gulf of Alaska (EGOA) skate fishery and GOA octopus fishery; Adopt final...

  17. Sensing the sea bed

    NASA Astrophysics Data System (ADS)

    2009-07-01

    William Wilcock and a team of scientists and engineers drilled holes in the sea floor, and inadvertently provided a breeding ground for octopuses, in their attempt to understand deep-ocean hydrothermal venting.

  18. 77 FR 33103 - Fisheries of the Economic Exclusive Zone Off Alaska; Shallow-Water Species Fishery by Vessels...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-05

    ... of the GOA (77 FR 15194, March 14, 2012), for the period 1200 hrs, A.l.t., April 1, 2012, through..., octopuses, and sculpins. This prohibition does not apply to fishing for pollock by vessels using...

  19. 77 FR 42193 - Fisheries of the Economic Exclusive Zone Off Alaska; Shallow-Water Species Fishery by Vessels...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-18

    ... specifications for groundfish of the GOA (77 FR 15194, March 14, 2012), for the period 1200 hrs, A.l.t., July 1..., octopuses, and sculpins. This prohibition does not apply to fishing for pollock by vessels using...

  20. Computer program for automatic generation of BWR control rod patterns

    SciTech Connect

    Taner, M.S.; Levine, S.H.; Hsia, M.Y. )

    1990-01-01

    A computer program named OCTOPUS has been developed to automatically determine a control rod pattern that approximates some desired target power distribution as closely as possible without violating any thermal safety or reactor criticality constraints. The program OCTOPUS performs a semi-optimization task based on the method of approximation programming (MAP) to develop control rod patterns. The SIMULATE-E code is used to determine the nucleonic characteristics of the reactor core state.

  1. Inspiration, simulation and design for smart robot manipulators from the sucker actuation mechanism of cephalopods.

    PubMed

    Grasso, Frank W; Setlur, Pradeep

    2007-12-01

    Octopus arms house 200-300 independently controlled suckers that can alternately afford an octopus fine manipulation of small objects and produce high adhesion forces on virtually any non-porous surface. Octopuses use their suckers to grasp, rotate and reposition soft objects (e.g., octopus eggs) without damaging them and to provide strong, reversible adhesion forces to anchor the octopus to hard substrates (e.g., rock) during wave surge. The biological 'design' of the sucker system is understood to be divided anatomically into three functional groups: the infundibulum that produces a surface seal that conforms to arbitrary surface geometry; the acetabulum that generates negative pressures for adhesion; and the extrinsic muscles that allow adhered surfaces to be rotated relative to the arm. The effector underlying these abilities is the muscular hydrostat. Guided by sensory input, the thousands of muscle fibers within the muscular hydrostats of the sucker act in coordination to provide stiffness or force when and where needed. The mechanical malleability of octopus suckers, the interdigitated arrangement of their muscle fibers and the flexible interconnections of its parts make direct studies of their control challenging. We developed a dynamic simulator (ABSAMS) that models the general functioning of muscular hydrostat systems built from assemblies of biologically constrained muscular hydrostat models. We report here on simulation studies of octopus-inspired and artificial suckers implemented in this system. These simulations reproduce aspects of octopus sucker performance and squid tentacle extension. Simulations run with these models using parameters from man-made actuators and materials can serve as tools for designing soft robotic implementations of man-made artificial suckers and soft manipulators.

  2. Ethnoecological knowledge of the artisan fishermen of octopi in the community of Coroa Vermelha.

    PubMed

    Martins, Viviane S; Schiavetti, Alexandre; Souto, Francisco J B

    2011-06-01

    Coral reefs are quite diverse ecosystems that carry out several ecological functions and plays a relevant socioeconomic role. The artisan fishing of octopi (Octopus spp.) is practiced for the survival of part of the inhabitants of Coroa Vermelha community, in the south of the state of Bahia. We intended to study the knowledge of the octopi fishermen of Coroa Vermelha using the comprehensive ethnoecological proposal of Marques. The data were collected between July, 2006 and April, 2008 through direct observation and from interviews with fishermen met by chance and through the "native specialists" criterion. Twenty semi-structured interviews were carried out following an itinerary of pre-established questions about the activity of octopi capture, and the biological and ecological aspects of the resource. The data showed that the fishermen have knowledge about biological and ecological aspects of the octopi. Two capture techniques are used: octopus fishing (polvejamento) in the reefs and through diving. Two specific folk are recognized: the "normal octopus" (Octopus insularis) and the "east octopus" (Octopus macropus (?)). The intervieews demonstrated ecological knowledge sometimes compatible with the scientific literature, mainly in which concerns the trophic ecology and behavior of the octopi. PMID:21670875

  3. Sodium pump molecular activity and membrane lipid composition in two disparate ectotherms, and comparison with endotherms.

    PubMed

    Turner, Nigel; Hulbert, A J; Else, Paul L

    2005-02-01

    Previous research has shown that the lower sodium pump molecular activity observed in tissues of ectotherms compared to endotherms, is largely related to the lower levels of polyunsaturates and higher levels of monounsaturates found in the cell membranes of ectotherms. Marine-based ectotherms, however, have very polyunsaturated membranes, and in the current study, we measured molecular activity and membrane lipid composition in tissues of two disparate ectothermic species, the octopus (Octopus vulgaris) and the bearded dragon lizard (Pogona vitticeps), to determine whether the high level of membrane polyunsaturation generally observed in marine-based ectotherms is associated with an increased sodium pump molecular activity relative to other ectotherms. Phospholipids from all tissues of the octopus were highly polyunsaturated and contained high concentrations of the omega-3 polyunsaturate, docosahexaenoic acid (22:6 (n-3)). In contrast, phospholipids from bearded dragon tissues contained higher proportions of monounsaturates and lower proportions of polyunsaturates. Sodium pump molecular activity was only moderately elevated in tissues of the octopus compared to the bearded dragon, despite the much greater level of polyunsaturation in octopus membranes. When the current data were combined with data for the ectothermic cane toad, a significant (P = 0.003) correlation was observed between sodium pump molecular activity and the content of 22:6 (n-3) in the surrounding membrane. These results are discussed in relation to recent work which shows a similar relationship in endotherms.

  4. Functional chondroitin sulfate from Enteroctopus dofleini containing a 3-O-sulfo glucuronic acid residue.

    PubMed

    Higashi, Kyohei; Okamoto, Yusuke; Mukuno, Ann; Wakai, Jun; Hosoyama, Saori; Linhardt, Robert J; Toida, Toshihiko

    2015-12-10

    There are several reports that chondroitin sulfate containing K-type units [GlcA (3S)-GalNAc (4S)] exhibiting similar levels of neurite outgrowth promoting activities as CS having high amounts of B-, D- and E-type disulfated disaccharides. Although CS containing K-type units possess important biological activities, there are only few sources, such as king crab cartilage, squid cartilage or sea cucumber. In this study, CS containing 13.9% of K-type units was found in octopus (Enteroctopus dofleini) cartilage using different substrate specificities of chondroitinases. The 2D NMR spectra showed cross-peaks assigned to protons on sugar ring of GlcA (3S), demonstrating the presence of K-type units in octopus CS. Furthermore, proportion of fucosylated disaccharide units in octopus CS was very low. Octopus CS showed high affinity for growth factors and stimulated neurite outgrowth of hippocampal neurons, similar to the activity of squid CS-E. These results strongly suggest that octopus cartilage is a rich source of CS-K and has important biological activities.

  5. Functional chondroitin sulfate from Enteroctopus dofleini containing a 3-O-sulfo glucuronic acid residue.

    PubMed

    Higashi, Kyohei; Okamoto, Yusuke; Mukuno, Ann; Wakai, Jun; Hosoyama, Saori; Linhardt, Robert J; Toida, Toshihiko

    2015-12-10

    There are several reports that chondroitin sulfate containing K-type units [GlcA (3S)-GalNAc (4S)] exhibiting similar levels of neurite outgrowth promoting activities as CS having high amounts of B-, D- and E-type disulfated disaccharides. Although CS containing K-type units possess important biological activities, there are only few sources, such as king crab cartilage, squid cartilage or sea cucumber. In this study, CS containing 13.9% of K-type units was found in octopus (Enteroctopus dofleini) cartilage using different substrate specificities of chondroitinases. The 2D NMR spectra showed cross-peaks assigned to protons on sugar ring of GlcA (3S), demonstrating the presence of K-type units in octopus CS. Furthermore, proportion of fucosylated disaccharide units in octopus CS was very low. Octopus CS showed high affinity for growth factors and stimulated neurite outgrowth of hippocampal neurons, similar to the activity of squid CS-E. These results strongly suggest that octopus cartilage is a rich source of CS-K and has important biological activities. PMID:26428158

  6. Phylogenetic relationships among major species of japanese coleoid cephalopods (Mollusca: Cephalopoda) using three mitochondrial DNA sequences.

    PubMed

    Takumiya, Mikio; Kobayashi, Mari; Tsuneki, Kazuhiko; Furuya, Hidetaka

    2005-02-01

    Phylogenetic relationships among 36 species of major coleoid cephalopods from Japanese waters were studied using partial sequences of three mitochondrial genes, 16S rDNA, 12S rDNA, and cytochrome c oxidase subunit I gene. Octopoda and Decapoda were monophylic groups. Within Sepioidea, Sepiadariidae and Sepiolidae were not closely related to Sepiidae, but rather related to Teuthoidea. Sepiidae with a distinct calcareous shell formed a single cluster. Myopsida was closely related to Oegopsida. Within Octopoda, Opisthoteuthis depressa and Argonauta argo diverged earlier than Octopodiidae. The common octopuses in Japanese waters were separated into three clusters. The first cluster occupied a basal position, and includes large-sized octopuses, such as Enteroctopus dofleini and Octopus (Paroctopus) conispadiceus from the continental shelf and upper slope. The second cluster consisted of long-armed octopuses, such as O. ornatus, O. minor, and O. sasakii. The third cluster contained small- to medium-sized octopus, such as Amphioctopus fangsiao, A. areolatus, O. cyaneus, and O. vulgaris, in which several species possess ocelli on the web. The second cluster formed the sister group to the third cluster. PMID:15738635

  7. Computer program for optimal BWR congtrol rod programming

    SciTech Connect

    Taner, M.S.; Levine, S.H.; Carmody, J.M.

    1995-12-31

    A fully automated computer program has been developed for designing optimal control rod (CR) patterns for boiling water reactors (BWRs). The new program, called OCTOPUS-3, is based on the OCTOPUS code and employs SIMULATE-3 (Ref. 2) for the analysis. There are three aspects of OCTOPUS-3 that make it successful for use at PECO Energy. It incorporates a new feasibility algorithm that makes the CR design meet all constraints, it has been coupled to a Bourne Shell program 3 to allow the user to run the code interactively without the need for a manual, and it develops a low axial peak to extend the cycle. For PECO Energy Co.`s limericks it increased the energy output by 1 to 2% over the traditional PECO Energy design. The objective of the optimization in OCTOPUS-3 is to approximate a very low axial peaked target power distribution while maintaining criticality, keeping the nodal and assembly peaks below the allowed maximum, and meeting the other constraints. The user-specified input for each exposure point includes: CR groups allowed-to-move, target k{sub eff}, and amount of core flow. The OCTOPUS-3 code uses the CR pattern from the previous step as the initial guess unless indicated otherwise.

  8. Phylogenetic relationships among major species of japanese coleoid cephalopods (Mollusca: Cephalopoda) using three mitochondrial DNA sequences.

    PubMed

    Takumiya, Mikio; Kobayashi, Mari; Tsuneki, Kazuhiko; Furuya, Hidetaka

    2005-02-01

    Phylogenetic relationships among 36 species of major coleoid cephalopods from Japanese waters were studied using partial sequences of three mitochondrial genes, 16S rDNA, 12S rDNA, and cytochrome c oxidase subunit I gene. Octopoda and Decapoda were monophylic groups. Within Sepioidea, Sepiadariidae and Sepiolidae were not closely related to Sepiidae, but rather related to Teuthoidea. Sepiidae with a distinct calcareous shell formed a single cluster. Myopsida was closely related to Oegopsida. Within Octopoda, Opisthoteuthis depressa and Argonauta argo diverged earlier than Octopodiidae. The common octopuses in Japanese waters were separated into three clusters. The first cluster occupied a basal position, and includes large-sized octopuses, such as Enteroctopus dofleini and Octopus (Paroctopus) conispadiceus from the continental shelf and upper slope. The second cluster consisted of long-armed octopuses, such as O. ornatus, O. minor, and O. sasakii. The third cluster contained small- to medium-sized octopus, such as Amphioctopus fangsiao, A. areolatus, O. cyaneus, and O. vulgaris, in which several species possess ocelli on the web. The second cluster formed the sister group to the third cluster.

  9. How vertebrate and invertebrate visual pigments differ in their mechanism of photoactivation

    PubMed Central

    Nakagawa, Masashi; Iwasa, Tatsuo; Kikkawa, Satoshi; Tsuda, Motoyuki; Ebrey, Thomas G.

    1999-01-01

    In vertebrate visual pigments, a glutamic acid serves as a negative counterion to the positively charged chromophore, a protonated Schiff base of retinal. When photoisomerization leads to the Schiff base deprotonating, the anionic glutamic acid becomes protonated, forming a neutral species that activates the visual cascade. We show that in octopus rhodopsin, the glutamic acid has no anionic counterpart. Thus, the “counterion” is already neutral, so no protonated form of an initially anionic group needs to be created to activate. This helps to explain another observation—that the active photoproduct of octopus rhodopsin can be formed without its Schiff base deprotonating. In this sense, the mechanism of light activation of octopus rhodopsin is simpler than for vertebrates, because it eliminates one of the steps required for vertebrate rhodopsins to achieve their activating state. PMID:10339563

  10. Predation Risk within Fishing Gear and Implications for South Australian Rock Lobster Fisheries

    PubMed Central

    Briceño, Felipe; Linnane, Adrian Joseph; Quiroz, Juan Carlos; Gardner, Caleb; Pecl, Gretta Tatyana

    2015-01-01

    Depredation of southern rock lobster (Jasus edwardsii) within fishing gear by the Maori octopus (Pinnoctopus cordiformis) has economic and ecological impacts on valuable fisheries in South Australia. In addition, depredation rates can be highly variable resulting in uncertainties for the fishery. We examined how in-pot lobster predation was influenced by factors such as lobster size and sex, season, fishing zone, and catch rate. Using mixed modelling techniques, we found that in-pot predation risk increased with lobster size and was higher for male lobsters. In addition, the effect of catch rate of lobsters on predation risk by octopus differed among fishing zones. There was both a seasonal and a spatial component to octopus predation, with an increased risk within discrete fishing grounds in South Australia at certain times of the year. Information about predation within lobster gear can assist fishery management decision-making, potentially leading to significant reduction in economic losses to the fishery. PMID:26489035

  11. Performance of an improved first generation optical CT scanner for 3D dosimetry

    NASA Astrophysics Data System (ADS)

    Qian, Xin; Adamovics, John; Wuu, Cheng-Shie

    2013-12-01

    Performance analysis of a modified 3D dosimetry optical scanner based on the first generation optical CT scanner OCTOPUS is presented. The system consists of PRESAGE™ dosimeters, the modified 3D scanner, and a new developed in-house user control panel written in Labview program which provides more flexibility to optimize mechanical control and data acquisition technique. The total scanning time has been significantly reduced from initial 8 h to ∼2 h by using the modified scanner. The functional performance of the modified scanner has been evaluated in terms of the mechanical integrity uncertainty of the data acquisition process. Optical density distribution comparison between the modified scanner, OCTOPUS and the treatment plan system has been studied. It has been demonstrated that the agreement between the modified scanner and treatment plans is comparable with that between the OCTOPUS and treatment plans.

  12. Predation Risk within Fishing Gear and Implications for South Australian Rock Lobster Fisheries.

    PubMed

    Briceño, Felipe; Linnane, Adrian Joseph; Quiroz, Juan Carlos; Gardner, Caleb; Pecl, Gretta Tatyana

    2015-01-01

    Depredation of southern rock lobster (Jasus edwardsii) within fishing gear by the Maori octopus (Pinnoctopus cordiformis) has economic and ecological impacts on valuable fisheries in South Australia. In addition, depredation rates can be highly variable resulting in uncertainties for the fishery. We examined how in-pot lobster predation was influenced by factors such as lobster size and sex, season, fishing zone, and catch rate. Using mixed modelling techniques, we found that in-pot predation risk increased with lobster size and was higher for male lobsters. In addition, the effect of catch rate of lobsters on predation risk by octopus differed among fishing zones. There was both a seasonal and a spatial component to octopus predation, with an increased risk within discrete fishing grounds in South Australia at certain times of the year. Information about predation within lobster gear can assist fishery management decision-making, potentially leading to significant reduction in economic losses to the fishery.

  13. Predation Risk within Fishing Gear and Implications for South Australian Rock Lobster Fisheries.

    PubMed

    Briceño, Felipe; Linnane, Adrian Joseph; Quiroz, Juan Carlos; Gardner, Caleb; Pecl, Gretta Tatyana

    2015-01-01

    Depredation of southern rock lobster (Jasus edwardsii) within fishing gear by the Maori octopus (Pinnoctopus cordiformis) has economic and ecological impacts on valuable fisheries in South Australia. In addition, depredation rates can be highly variable resulting in uncertainties for the fishery. We examined how in-pot lobster predation was influenced by factors such as lobster size and sex, season, fishing zone, and catch rate. Using mixed modelling techniques, we found that in-pot predation risk increased with lobster size and was higher for male lobsters. In addition, the effect of catch rate of lobsters on predation risk by octopus differed among fishing zones. There was both a seasonal and a spatial component to octopus predation, with an increased risk within discrete fishing grounds in South Australia at certain times of the year. Information about predation within lobster gear can assist fishery management decision-making, potentially leading to significant reduction in economic losses to the fishery. PMID:26489035

  14. Alternative diets for maintaining and rearing cephalopods in captivity.

    PubMed

    DeRusha, R H; Forsythe, J W; DiMarco, F P; Hanlon, R T

    1989-07-01

    The requirement of live marine prey for cephalopod mariculture has restricted its practicality for inland research laboratories, commercial enterprises and home aquarists. We evaluated acceptability and resultant growth on: (a) frozen marine shrimps, (b) live and frozen marine polychaete worms, (c) live and frozen marine crabs, (d) frozen marine fishes, (e) live adult brine shrimp, (f) live freshwater fish and (g) live freshwater crayfish. The diets were presented for periods of 2 to 11 weeks to octopuses, cuttlefishes or squids and in most trials the results were compared to animals fed control diets of live marine shrimps, crabs or fish. Overall, frozen marine shrimp proved to be the best alternative diet tested. Adult Octopus maya on frozen marine shrimp diets grew as well as those on control diets at 2.8% body weight per day (%/d) compared to 2.0%/d on live freshwater crayfish, 1.4%/d on live marine polychaete worms and 0.8%/d on live freshwater fish (Tilapia sp.). Juvenile Octopus maya and Octopus bimaculoides also grew comparably to controls when fed frozen marine shrimps; growth rates ranged from near 3.0%/d at 3 months of age to nearly 2.5%/d at 6 months of age. Thus, these alternatives are acceptable as the octopuses end their exponential growth phase at an age of 3 - 5 months. Attempts to rear O. maya hatchlings and juveniles (up to 1 month of age) on dead foods resulted in high mortality and slow or negative growth. No live or dead alternative diet has been found yet that will promote good growth and survival in hatchling octopuses. Hatchling F3 generation Sepia officinalis (the European cuttlefish) were reared for 6 weeks exclusively on adult brine shrimp (Artemia salina).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2761235

  15. The Fine Structure of Some Retinal Photoreceptors

    PubMed Central

    Moody, M. F.; Robertson, J. D.

    1960-01-01

    An electron microscope study has been made of octopus and amphibian photoreceptors, after fixing with KMnO4 and embedding in araldite. What has previously been seen as a single dense stratum bounding the tubular compartments (octopus) or the double membrane discs (rods and cones), now shows a double structure. We interpret this as showing that these tubules and discs have similar bounding surfaces, which are probably directly related to the cell membrane. This is confirmed by the finding that the tubules and discs are (at least occasionally) continuous with the cell membrane. PMID:14423794

  16. Method for depleting BWRs using optimal control rod patterns

    SciTech Connect

    Taner, M.S.; Levine, S.H. ); Hsiao, M.Y. )

    1991-01-01

    Control rod (CR) programming is an essential core management activity for boiling water reactors (BWRs). After establishing a core reload design for a BWR, CR programming is performed to develop a sequence of exposure-dependent CR patterns that assure the safe and effective depletion of the core through a reactor cycle. A time-variant target power distribution approach has been assumed in this study. The authors have developed OCTOPUS to implement a new two-step method for designing semioptimal CR programs for BWRs. The optimization procedure of OCTOPUS is based on the method of approximation programming and uses the SIMULATE-E code for nucleonics calculations.

  17. Phylogenetic relationships among Octopodidae species in coastal waters of China inferred from two mitochondrial DNA gene sequences.

    PubMed

    Lü, Z M; Cui, W T; Liu, L Q; Li, H M; Wu, C W

    2013-09-19

    Octopus in the family Octopodidae (Mollusca: Cephalopoda) has been generally recognized as a "catch-all" genus. The monophyly of octopus species in China's coastal waters has not yet been studied. In this paper, we inferred the phylogeny of 11 octopus species (family Octopodidae) in China's coastal waters using nucleotide sequences of two mitochondrial DNA genes: cytochrome c oxidase subunit I (COI) and 16S rRNA. Sequence analysis of both genes revealed that the 11 species of Octopodidae fell into four distinct groups, which were genetically distant from one another and exhibited identical phylogenetic resolution. The phylogenies indicated strongly that the genus Octopus in China's coastal waters is also not monophyletic, and it is therefore clear that the Octopodidae systematics in this area requires major revision. It is demonstrated that partial sequence information of both the mitochondrial genes 16S rRNA and COI could be used as diagnostic molecular markers in the identification and resolution of the taxonomic ambiguity of Octopodidae species.

  18. A flow visualization study of single-arm sculling movement emulating cephalopod thrust generation

    NASA Astrophysics Data System (ADS)

    Kazakidi, Asimina; Gnanamanickam, Ebenezer P.; Tsakiris, Dimitris P.; Ekaterinaris, John A.

    2014-11-01

    In addition to jet propulsion, octopuses use arm-swimming motion as an effective means of generating bursts of thrust, for hunting, defense, or escape. The individual role of their arms, acting as thrust generators during this motion, is still under investigation, in view of an increasing robotic interest for alternative modes of propulsion, inspired by the octopus. Computational studies have revealed that thrust generation is associated with complex vortical flow patterns in the wake of the moving arm, however further experimental validation is required. Using the hydrogen bubble technique, we studied the flow disturbance around a single octopus-like robotic arm, undergoing two-stroke sculling movements in quiescent fluid. Although simplified, sculling profiles have been found to adequately capture the fundamental kinematics of the octopus arm-swimming behavior. In fact, variation of the sculling parameters alters considerably the generation of forward thrust. Flow visualization revealed the generation of complex vortical structures around both rigid and compliant arms. Increased disturbance was evident near the tip, particularly at the transitional phase between recovery and power strokes. These results are in good qualitative agreement with computational and robotic studies. Work funded by the ESF-GSRT HYDRO-ROB Project PE7(281).

  19. 77 FR 22683 - Fisheries of the Exclusive Economic Zone Off Alaska; Gulf of Alaska; Final 2012 and 2013 Harvest...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ... 14, 2012 (77 FR 15194). A table providing information on 2012 GOA non-American Fisheries Act (AFA... 14, 2012 (77 FR 15194), the following corrections are made to Table 22: 1. On page 15216, in Table 22...,028 106 Octopuses Annual Gulfwide 0.0176 1,455 26 Sculpins Annual Gulfwide 0.0176 5,731 101 \\1\\...

  20. 75 FR 38454 - Fisheries of the Exclusive Economic Zone Off Alaska; Skates Management in the Bering Sea and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-02

    ... accountability measures (AMs) and conform to the National Standard 1 (NS1) guidelines (74 FR 3178, January 16...'' category in response to a rapidly developing directed fishery (69 FR 26313, May 12, 2004). A retrospective... and AMs must be implemented by January 1, 2011. Skate, shark, sculpin, and octopus groups...

  1. 75 FR 5541 - Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands; Final 2009...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-03

    ...). General regulations governing U.S. fisheries also appear at 50 CFR part 600. On February 17, 2009 (74 FR... temporary rule (FR Doc. E9-3297) published on February 17, 2009, at 74 FR 7359, is corrected as follows: On... monitoring includes sculpins, sharks, skates, and octopus. Classification This action is authorized under...

  2. Sensational Sea Life: A Teacher-Friendly Thematic Unit [with CD-ROM]. R.E.A.D. A.N.D. F.E.E.D. Series.

    ERIC Educational Resources Information Center

    Klingborg, Beverly; Cardinalli, Antonina

    This book is the second in a series of thematic units designed especially for children who are deaf and hard of hearing in kindergarten through the elementary grades. The unit focuses on sea creatures and is divided into seven sections. Five sections contain lessons on particular sea animals including whales, turtles, starfish, octopuses, and…

  3. Continuum robot arms inspired by cephalopods

    NASA Astrophysics Data System (ADS)

    Walker, Ian D.; Dawson, Darren M.; Flash, Tamar; Grasso, Frank W.; Hanlon, Roger T.; Hochner, Binyamin; Kier, William M.; Pagano, Christopher C.; Rahn, Christopher D.; Zhang, Qiming M.

    2005-05-01

    In this paper, we describe our recent results in the development of a new class of soft, continuous backbone ("continuum") robot manipulators. Our work is strongly motivated by the dexterous appendages found in cephalopods, particularly the arms and suckers of octopus, and the arms and tentacles of squid. Our ongoing investigation of these animals reveals interesting and unexpected functional aspects of their structure and behavior. The arrangement and dynamic operation of muscles and connective tissue observed in the arms of a variety of octopus species motivate the underlying design approach for our soft manipulators. These artificial manipulators feature biomimetic actuators, including artificial muscles based on both electro-active polymers (EAP) and pneumatic (McKibben) muscles. They feature a "clean" continuous backbone design, redundant degrees of freedom, and exhibit significant compliance that provides novel operational capacities during environmental interaction and object manipulation. The unusual compliance and redundant degrees of freedom provide strong potential for application to delicate tasks in cluttered and/or unstructured environments. Our aim is to endow these compliant robotic mechanisms with the diverse and dexterous grasping behavior observed in octopuses. To this end, we are conducting fundamental research into the manipulation tactics, sensory biology, and neural control of octopuses. This work in turn leads to novel approaches to motion planning and operator interfaces for the robots. The paper describes the above efforts, along with the results of our development of a series of continuum tentacle-like robots, demonstrating the unique abilities of biologically-inspired design.

  4. 76 FR 59064 - Fisheries of the Exclusive Economic Zone Off Alaska; Shallow-Water Species by Vessels Using Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-23

    ... under Sec. 679.21(d)(7)(i) on September 3, 2011 (76 FR 55726, September 7, 2011) and subsequent reopener from September 14, 2011 to September 16, 2011 (76 FR 57679, September 16, 2011). As of September 19..., sharks, sculpins, and octopus. Classification This action responds to the best available...

  5. 75 FR 11778 - Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands; Final 2010...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... on December 2, 2009 (74 FR 63100). Comments were invited and accepted through January 4, 2010. NMFS... 2010 and 2011 harvest specifications (74 FR 63100, December 2, 2009) based largely on information...\\ ``Other species'' includes sculpins, sharks, skates, and octopus. Forage fish, as defined at Sec....

  6. Draft Genome Sequence of the Moderately Thermophilic Bacterium Schleiferia thermophila Strain Yellowstone (Bacteroidetes).

    PubMed

    Thiel, Vera; Hamilton, Trinity L; Tomsho, Lynn P; Burhans, Richard; Gay, Scott E; Ramaley, Robert F; Schuster, Stephan C; Steinke, Laurey; Bryant, Donald A

    2014-08-28

    The draft genome sequence of the moderately thermophilic bacterium Schleiferia thermophila strain Yellowstone (Bacteroidetes), isolated from Octopus Spring (Yellowstone National Park, WY, USA) was sequenced and comprises 2,617,694 bp in 35 contigs. The draft genome is predicted to encode 2,457 protein coding genes and 37 tRNA encoding genes and two rRNA operons.

  7. 75 FR 76352 - Fisheries of the Exclusive Economic Zone Off Alaska; Gulf of Alaska; Proposed 2011 and 2012...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-08

    ... final rule to implement Amendment 87 to the FMP on October 6, 2010 (75 FR 61639), effective November 5... respect to the management of octopuses. The Council, in response to the fishing industry's concerns that... Register on March 12, 2010 (75 FR 11749) . The exceptions to this are the establishment of individual...

  8. Black Studies: A Key to the Future

    ERIC Educational Resources Information Center

    Johnson, Whittington B.; Nichols, Ted

    1977-01-01

    Concludes that black studies programs should develop an octopus-like academic structure which reaches out in several directions, simultaneously: initiating and illuminating, discerning and fostering, observing and directing, collecting and disseminating; all with one goal in view, exploring the black experience within a universal perspective.…

  9. Rooting for radium

    NASA Astrophysics Data System (ADS)

    2008-05-01

    Willard Moore and his colleagues collected 200-litre samples of sea water from depths of up to 1,000 metres and stirred up the odd octopus in order to determine the input of submarine groundwater discharge into the Atlantic Ocean.

  10. Cavitational Iron Microparticles Generation By Plasma Procedures For Medical Applications

    NASA Astrophysics Data System (ADS)

    Bica, Ioan; Bunoiu, Madalin; Chirigiu, Liviu; Spunei, Marius; Juganaru, Iulius

    2012-12-01

    The paper presents the experimental installation for the production, in argon plasma, of cavitational iron microparticles (pore microspheres, microtubes and octopus-shaped microparticles). Experimental results are presented and discussed and it is shown that absorbant particles with a minimum iron content are obtained by the plasma procedures

  11. Optics clustered to output unique solutions: A multi-laser facility for combined single molecule and ensemble microscopy

    NASA Astrophysics Data System (ADS)

    Clarke, David T.; Botchway, Stanley W.; Coles, Benjamin C.; Needham, Sarah R.; Roberts, Selene K.; Rolfe, Daniel J.; Tynan, Christopher J.; Ward, Andrew D.; Webb, Stephen E. D.; Yadav, Rahul; Zanetti-Domingues, Laura; Martin-Fernandez, Marisa L.

    2011-09-01

    Optics clustered to output unique solutions (OCTOPUS) is a microscopy platform that combines single molecule and ensemble imaging methodologies. A novel aspect of OCTOPUS is its laser excitation system, which consists of a central core of interlocked continuous wave and pulsed laser sources, launched into optical fibres and linked via laser combiners. Fibres are plugged into wall-mounted patch panels that reach microscopy end-stations in adjacent rooms. This allows multiple tailor-made combinations of laser colours and time characteristics to be shared by different end-stations minimising the need for laser duplications. This setup brings significant benefits in terms of cost effectiveness, ease of operation, and user safety. The modular nature of OCTOPUS also facilitates the addition of new techniques as required, allowing the use of existing lasers in new microscopes while retaining the ability to run the established parts of the facility. To date, techniques interlinked are multi-photon/multicolour confocal fluorescence lifetime imaging for several modalities of fluorescence resonance energy transfer (FRET) and time-resolved anisotropy, total internal reflection fluorescence, single molecule imaging of single pair FRET, single molecule fluorescence polarisation, particle tracking, and optical tweezers. Here, we use a well-studied system, the epidermal growth factor receptor network, to illustrate how OCTOPUS can aid in the investigation of complex biological phenomena.

  12. Sex Education in Rural Churches.

    ERIC Educational Resources Information Center

    Isberner, Fred R.; And Others

    1990-01-01

    Describes Open Communication Teens or Parents Understanding Sexuality (OCTOPUS), rural teenage pregnancy prevention program. Program presented in religious setting to improve sexual attitudes and parent-child communication. Finds that participants generally gained in knowledge and self-assessment, but teenagers showed no improvement in attitude…

  13. Draft Genome Sequence of the Deinococcus-Thermus Bacterium Meiothermus ruber Strain A

    SciTech Connect

    Thiel, Vera; Tomsho, Lynn P.; Burhans, Richard; Gay, Scott E.; Schuster, Stephan C.; Ward, David M.; Bryant, Donald A.

    2015-03-26

    The draft genome sequence of the Deinococcus-Thermus group bacterium Meiothermus ruber strain A, isolated from a cyanobacterial enrichment culture obtained from Octopus Spring (Yellowstone National Park, WY), comprises 2,968,099 bp in 170 contigs. It is predicted to contain 2,895 protein-coding genes, 44 tRNA-coding genes, and 2 rRNA operons.

  14. Marine envenomations.

    PubMed

    Balhara, Kamna S; Stolbach, Andrew

    2014-02-01

    This article describes the epidemiology and presentation of human envenomation from marine organisms. Venom pathophysiology, envenomation presentation, and treatment options are discussed for sea snake, stingray, spiny fish, jellyfish, octopus, cone snail, sea urchin, and sponge envenomation. The authors describe the management of common exposures that cause morbidity as well as the keys to recognition and treatment of life-threatening exposures. PMID:24275176

  15. Optics clustered to output unique solutions: a multi-laser facility for combined single molecule and ensemble microscopy.

    PubMed

    Clarke, David T; Botchway, Stanley W; Coles, Benjamin C; Needham, Sarah R; Roberts, Selene K; Rolfe, Daniel J; Tynan, Christopher J; Ward, Andrew D; Webb, Stephen E D; Yadav, Rahul; Zanetti-Domingues, Laura; Martin-Fernandez, Marisa L

    2011-09-01

    Optics clustered to output unique solutions (OCTOPUS) is a microscopy platform that combines single molecule and ensemble imaging methodologies. A novel aspect of OCTOPUS is its laser excitation system, which consists of a central core of interlocked continuous wave and pulsed laser sources, launched into optical fibres and linked via laser combiners. Fibres are plugged into wall-mounted patch panels that reach microscopy end-stations in adjacent rooms. This allows multiple tailor-made combinations of laser colours and time characteristics to be shared by different end-stations minimising the need for laser duplications. This setup brings significant benefits in terms of cost effectiveness, ease of operation, and user safety. The modular nature of OCTOPUS also facilitates the addition of new techniques as required, allowing the use of existing lasers in new microscopes while retaining the ability to run the established parts of the facility. To date, techniques interlinked are multi-photon/multicolour confocal fluorescence lifetime imaging for several modalities of fluorescence resonance energy transfer (FRET) and time-resolved anisotropy, total internal reflection fluorescence, single molecule imaging of single pair FRET, single molecule fluorescence polarisation, particle tracking, and optical tweezers. Here, we use a well-studied system, the epidermal growth factor receptor network, to illustrate how OCTOPUS can aid in the investigation of complex biological phenomena.

  16. Application of FRAMIS to K/sub D/ data

    SciTech Connect

    Storch, N.

    1980-03-20

    This report documents an application of the FRAMIS relational data base management system. A geochemical data base of ion exchange distribution coefficients (K/sub D/) is created and maintained by using very simple commands. Reports are automatically generated. Familiarity with the LLL Octopus Time-Sharing System and FRAMIS is assumed.

  17. Hearing characteristics of cephalopods: modeling and environmental impact study.

    PubMed

    Zhang, Yunfeng; Shi, Feng; Song, Jiakun; Zhang, Xugang; Yu, Shiliang

    2015-01-01

    Cephalopods (octopus, squid and cuttlefish) are some of the most intriguing molluscs, and they represent economically important commercial marine species for fisheries. Previous studies have shown that cephalopods are sensitive to underwater particle motion, especially at low frequencies in the order of 10 Hz. The present paper deals with quantitative modeling of the statocyst system in three cephalopod species: Octopus vulgaris, Sepia officinalis and Loligo vulgaris. The octopus's macula/statolith organ was modeled as a 2nd-order dynamic oscillator using parameter values estimated from scanning electron micrograph images. The modeling results agree reasonably well with experimental data (acceleration threshold) in the three cephalopod species. Insights made from quantitative modeling and simulating the particle motion sensing mechanism of cephalopods elucidated their underwater particle motion detection capabilities. Sensitivity to emerging environmental issues, such as low frequency noise caused by near-shore wind farms and increasing levels of carbon dioxide in the ocean, and sensitivity to sounds produced by impending landslides were investigated in octopus using the model. PMID:24920389

  18. Electronics Engineering Department, EE technical review

    SciTech Connect

    Not Available

    1983-12-01

    Progress is briefly summarized in the following areas: a microprocessor-controlled octopus line-switching network, implementation of CAMAC-based interlocks on the Mirror Fusion Test Facility, fiber optics in the nuclear test program, protection circuits and instrumentation interface for long-pulse MFTF neutral beams, and a high-power pulsed microwave source designated MGX. (LEW)

  19. User's guide for the ICS (Integrated Communications System) database system: Version 1. 1

    SciTech Connect

    Konrad, A.

    1987-08-01

    The ICS database was implemented in support of the Integrated Communications System (ICS) Project. Additionally, it is linked to the LBLSTAFF database using the OCTOPUS, ICS, and SERVICE subfiles so that staff need not maintain employee information such as mailstop, payroll account number, termination date, etc. This relieves the staff of tracking mailstop changes and other personal information.

  20. Data analysis using multiple filters

    SciTech Connect

    Nakanishi, K.K.; Burr, N.C.

    1982-08-25

    Several programs have been written for the OCTOPUS and LLNL Seismic Observatory's PRIME computer system. These programs are used to compute spectral amplitude as a function of time for various frequency bands, and to display the results using either contour levels or color graphics.

  1. Self-assembly of polymeric micelles into complex but regular superstructures based on highly controllable core-core fusion between the micelles.

    PubMed

    Wang, Liangyan; Wang, Yafen; Miao, Han; Chen, Daoyong

    2016-06-14

    Herein, we report a facile but highly controllable method to induce core-core fusion for not only spherical but also worm-like polymeric micelles, leading to various complex but regular superstructures including "random worm-like co-micelles", "block worm-like co-micelles" and octopus-like superparticles. PMID:27192018

  2. DASLL: design automation system at Lawrence Livermore. User's reference manual

    SciTech Connect

    Magnuson, W.G. Jr.; Willett, G.W.

    1980-04-01

    This manual shows how to use the DASLL system to lay out printed circuit boards using the OCTOPUS CDC 7600 computer system and other equipment at Lawrence Livermore Laboratory. This information will also be found very useful for those converting or analyzing the DASLL system.

  3. Hearing characteristics of cephalopods: modeling and environmental impact study.

    PubMed

    Zhang, Yunfeng; Shi, Feng; Song, Jiakun; Zhang, Xugang; Yu, Shiliang

    2015-01-01

    Cephalopods (octopus, squid and cuttlefish) are some of the most intriguing molluscs, and they represent economically important commercial marine species for fisheries. Previous studies have shown that cephalopods are sensitive to underwater particle motion, especially at low frequencies in the order of 10 Hz. The present paper deals with quantitative modeling of the statocyst system in three cephalopod species: Octopus vulgaris, Sepia officinalis and Loligo vulgaris. The octopus's macula/statolith organ was modeled as a 2nd-order dynamic oscillator using parameter values estimated from scanning electron micrograph images. The modeling results agree reasonably well with experimental data (acceleration threshold) in the three cephalopod species. Insights made from quantitative modeling and simulating the particle motion sensing mechanism of cephalopods elucidated their underwater particle motion detection capabilities. Sensitivity to emerging environmental issues, such as low frequency noise caused by near-shore wind farms and increasing levels of carbon dioxide in the ocean, and sensitivity to sounds produced by impending landslides were investigated in octopus using the model.

  4. The dark side of the mushroom spring microbial mat: Life in the shadow of chlorophototrophs. I. Microbial diversity based on 16S rRNA gene amplicons and metagenomics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microbial-mat communities in the effluent channels of Octopus and Mushroom Springs within the Lower Geyser Basin at Yellowstone National Park have been studied for nearly 50 years. The emphasis has mostly focused on the chlorophototrophic bacterial organisms of the phyla Cyanobacteria and Chloroflex...

  5. The hemocyanin from a living fossil, the cephalopod Nautilus pompilius: protein structure, gene organization, and evolution.

    PubMed

    Bergmann, Sandra; Lieb, Bernhard; Ruth, Peter; Markl, Jürgen

    2006-03-01

    By electron microscopic and immunobiochemical analyses we have confirmed earlier evidence that Nautilus pompilius hemocyanin (NpH) is a ring-like decamer (M(r) = approximately 3.5 million), assembled from 10 identical copies of an approximately 350-kDa polypeptide. This subunit in turn is substructured into seven sequential covalently linked functional units of approximately 50 kDa each (FUs a-g). We have cloned and sequenced the cDNA encoding the complete polypeptide; it comprises 9198 bp and is subdivided into a 5' UTR of 58 bp, a 3' UTR of 365 bp, and an open reading frame for a signal peptide of 21 amino acids plus a polypeptide of 2903 amino acids (M(r) = 335,881). According to sequence alignments, the seven FUs of Nautilus hemocyanin directly correspond to the seven FU types of the previously sequenced hemocyanin "OdH" from the cephalopod Octopus dofleini. Thirteen potential N-glycosylation sites are distributed among the seven Nautilus hemocyanin FUs; the structural consequences of putatively attached glycans are discussed on the basis of the published X-ray structure for an Octopus dofleini and a Rapana thomasiana FU. Moreover, the complete gene structure of Nautilus hemocyanin was analyzed; it resembles that of Octopus hemocyanin with respect to linker introns but shows two internal introns that differ in position from the three internal introns of the Octopus hemocyanin gene. Multiple sequence alignments allowed calculation of a rather robust phylogenetic tree and a statistically firm molecular clock. This reveals that the last common ancestor of Nautilus and Octopus lived 415 +/- 24 million years ago, in close agreement with fossil records from the early Devonian. PMID:16501879

  6. Referential gestures in fish collaborative hunting.

    PubMed

    Vail, Alexander L; Manica, Andrea; Bshary, Redouan

    2013-01-01

    In humans, referential gestures intentionally draw the attention of a partner to an object of mutual interest, and are considered a key element in language development. Outside humans, referential gestures have only been attributed to great apes and, most recently, ravens. This was interpreted as further evidence for the comparable cognitive abilities of primates and corvids. Here we describe a signal that coral reef fishes, the grouper Plectropomus pessuliferus marisrubri and coral trout Plectropomus leopardus, use to indicate hidden prey to cooperative hunting partners, including giant moray eels Gymnothorax javanicus, Napoleon wrasses Chelinus undulatus and octopuses Octopus cyanea. We provide evidence that the signal possesses the five attributes proposed to infer a referential gesture: it is directed towards an object, mechanically ineffective, directed towards a potential recipient, receives a voluntary response and demonstrates hallmarks of intentionality. Thus, referential gesture use is not restricted to large-brained vertebrates.

  7. Evolution of multicellular animals as deduced from 5S rRNA sequences: a possible early emergence of the Mesozoa.

    PubMed Central

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

    1984-01-01

    The nucleotide sequences of 5S rRNA from a mesozoan Dicyema misakiense and three metazoan species, i.e., an acorn-worm Saccoglossus kowalevskii, a moss-animal Bugula neritina, and an octopus Octopus vulgaris have been determined. A phylogenic tree of multicellular animals has been constructed from 73 5S rRNA sequences available at present including those from the above four sequences. The tree suggests that the mesozoan is the most ancient multicellular animal identified so far, its emergence time being almost the same as that of flagellated or ciliated protozoans. The branching points of planarians and nematodes are a little later than that of the mesozoan but are clearly earlier than other metazoan groups including sponges and jellyfishes. Many metazoan groups seem to have diverged within a relatively short period. PMID:6539911

  8. Evolution of multicellular animals as deduced from 5S rRNA sequences: a possible early emergence of the Mesozoa.

    PubMed

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

    1984-06-25

    The nucleotide sequences of 5S rRNA from a mesozoan Dicyema misakiense and three metazoan species, i.e., an acorn-worm Saccoglossus kowalevskii, a moss-animal Bugula neritina, and an octopus Octopus vulgaris have been determined. A phylogenic tree of multicellular animals has been constructed from 73 5S rRNA sequences available at present including those from the above four sequences. The tree suggests that the mesozoan is the most ancient multicellular animal identified so far, its emergence time being almost the same as that of flagellated or ciliated protozoans. The branching points of planarians and nematodes are a little later than that of the mesozoan but are clearly earlier than other metazoan groups including sponges and jellyfishes. Many metazoan groups seem to have diverged within a relatively short period.

  9. Evolution of multicellular animals as deduced from 5S rRNA sequences: a possible early emergence of the Mesozoa.

    PubMed

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

    1984-06-25

    The nucleotide sequences of 5S rRNA from a mesozoan Dicyema misakiense and three metazoan species, i.e., an acorn-worm Saccoglossus kowalevskii, a moss-animal Bugula neritina, and an octopus Octopus vulgaris have been determined. A phylogenic tree of multicellular animals has been constructed from 73 5S rRNA sequences available at present including those from the above four sequences. The tree suggests that the mesozoan is the most ancient multicellular animal identified so far, its emergence time being almost the same as that of flagellated or ciliated protozoans. The branching points of planarians and nematodes are a little later than that of the mesozoan but are clearly earlier than other metazoan groups including sponges and jellyfishes. Many metazoan groups seem to have diverged within a relatively short period. PMID:6539911

  10. New measurements of radial velocities in clusters of galaxies. II

    NASA Astrophysics Data System (ADS)

    Proust, D.; Mazure, A.; Sodre, L.; Capelato, H.; Lund, G.

    1988-03-01

    Heliocentric radial velocities are determined for 100 galaxies in five clusters, on the basis of 380-518-nm observations obtained using a CCD detector coupled by optical fibers to the OCTOPUS multiobject spectrograph at the Cassegrain focus of the 3.6-m telescope at ESO La Silla. The data-reduction procedures and error estimates are discussed, and the results are presented in tables and graphs and briefly characterized.

  11. Draft Genome Sequence of the Moderately Thermophilic Bacterium Schleiferia thermophila Strain Yellowstone (Bacteroidetes)

    PubMed Central

    Thiel, Vera; Hamilton, Trinity L.; Tomsho, Lynn P.; Burhans, Richard; Gay, Scott E.; Ramaley, Robert F.; Schuster, Stephan C.; Steinke, Laurey

    2014-01-01

    The draft genome sequence of the moderately thermophilic bacterium Schleiferia thermophila strain Yellowstone (Bacteroidetes), isolated from Octopus Spring (Yellowstone National Park, WY, USA) was sequenced and comprises 2,617,694 bp in 35 contigs. The draft genome is predicted to encode 2,457 protein coding genes and 37 tRNA encoding genes and two rRNA operons. PMID:25169864

  12. Corrigendum: First principles calculation of field emission from nanostructures using time-dependent density functional theory: A simplified approach

    NASA Astrophysics Data System (ADS)

    Tawfik, Sherif A.; El-Sheikh, S. M.; Salem, N. M.

    2016-09-01

    Recently we have become aware that the description of the quantum wave functions in Sec. 2.1 is incorrect. In the published version of the paper, we have stated that the states are expanded in terms of plane waves. However, the correct description of the quantum states in the context of the real space implementation (using the Octopus code) is that states are represented by discrete points in a real space grid.

  13. Study of Optimal Perimetric Testing in Children (OPTIC): Feasibility, Reliability and Repeatability of Perimetry in Children

    PubMed Central

    Patel, Dipesh E.; Cumberland, Phillippa M.; Walters, Bronwen C.; Russell-Eggitt, Isabelle; Rahi, Jugnoo S.

    2015-01-01

    Purpose To investigate feasibility, reliability and repeatability of perimetry in children. Methods A prospective, observational study recruiting 154 children aged 5–15 years, without an ophthalmic condition that affects the visual field (controls), identified consecutively between May 2012 and November 2013 from hospital eye clinics. Perimetry was undertaken in a single sitting, with standardised protocols, in a randomised order using the Humphrey static (SITA 24–2 FAST), Goldmann and Octopus kinetic perimeters. Data collected included test duration, subjective experience and test quality (incorporating examiner ratings on comprehension of instructions, fatigue, response to visual and auditory stimuli, concentration and co-operation) to assess feasibility and reliability. Testing was repeated within 6 months to assess repeatability. Results Overall feasibility was very high (Goldmann=96.1%, Octopus=89% and Humphrey=100% completed the tests). Examiner rated reliability was ‘good’ in 125 (81.2%) children for Goldmann, 100 (64.9%) for Octopus and 98 (63.6%) for Humphrey perimetry. Goldmann perimetry was the most reliable method in children under 9 years of age. Reliability improved with increasing age (multinomial logistic regression (Goldmann, Octopus and Humphrey), p<0.001). No significant differences were found for any of the three test strategies when examining initial and follow-up data outputs (Bland-Altman plots, n=43), suggesting good test repeatability, although the sample size may preclude detection of a small learning effect. Conclusions Feasibility and reliability of formal perimetry in children improves with age. By the age of 9 years, all the strategies used here were highly feasible and reliable. Clinical assessment of the visual field is achievable in children as young as 5 years, and should be considered where visual field loss is suspected. Since Goldmann perimetry is the most effective strategy in children aged 5–8 years and this

  14. ATA diagnostic data handling system: an overview

    SciTech Connect

    Chambers, F.W.; Kallman, J.; McDonald, J.; Slominski, M.

    1984-06-14

    The functions to be performed by the ATA diagnostic data handling system are discussed. The capabilities of the present data acquisition system (System 0) are presented. The goals for the next generation acquisition system (System 1), currently under design, are discussed. Facilities on the Octopus system for data handling are reviewed. Finally, we discuss what has been learned about diagnostics and computer based data handling during the past year.

  15. Some LLNL (Lawrence Livermore National Laboratory) experience on the CRAY X-MP/24

    SciTech Connect

    Nelson, H.

    1984-03-01

    The historical situation leading to LLNL's use of an X-P/2 is briefly covered. The configuration of the LLNL machine and its place in the Octopus network is shown. The basic equation of multi-processing performance is introduced and some typical cases are mentioned. The performance of three codes: (1) Tim Axelrods' version of SIMPLE; (2) the Class-7 test; and (3) the Cray-Blitz chess program are discussed.

  16. Program TOMSCAT

    SciTech Connect

    Frank, A.M.

    1980-05-30

    Program TOMSCAT is an interactive code that calculates the scattering spectrum and background for a Thomson-scattering diagnostic in typical magnetic fusion plasmas. Thomson scattering yields values of the plasma electron temperature T/sub e/ and electron density N/sub e/. This program is intended as an aid for designing Thomson-scattering systems, so all experimental parameters are input by the user. The code is operational on OCTOPUS.

  17. Network evaluation for F-Division

    SciTech Connect

    Boyd, J.K.; Carr, R.B.; Lee, F.D.

    1986-05-16

    This report contains an evaluation of the computer and computer network needs of F-Division. The main intent is to identify ways in which all computational aspects of F-Division might interact more effectively. This includes the physics, engineering, and clerical staffs. Consideration is given to usage of the Octopus computer system, computer control of experiments, data analysis, computer aided design (CAD) and word processing issues.

  18. Inducibility of human atrial fibrillation in an in silico model reflecting local acetylcholine distribution and concentration.

    PubMed

    Hwang, Minki; Lee, Hyun-Seung; Pak, Hui-Nam; Shim, Eun Bo

    2016-01-01

    Vagal nerve activity has been known to play a crucial role in the induction and maintenance of atrial fibrillation (AF). However, it is unclear how the distribution and concentration of local acetylcholine (ACh) promotes AF. In this study, we investigated the effect of the spatial distribution and concentration of ACh on fibrillation patterns in an in silico human atrial model. A human atrial action potential model with an ACh-dependent K(+) current (IKAch) was used to examine the effect of vagal activation. A simulation of cardiac wave dynamics was performed in a realistic 3D model of the atrium. A model of the ganglionated plexus (GP) and nerve was developed based on the "octopus hypothesis". The pattern of cardiac wave dynamics was examined by applying vagal activation to the GP areas or randomly. AF inducibility in the octopus hypothesis-based GP and nerve model was tested. The effect of the ACh concentration level was also examined. In the single cell simulation, an increase in the ACh concentration shortened APD90 and increased the maximal slope of the restitution curve. In the 3D simulation, a random distribution of vagal activation promoted wavebreaks while ACh secretion limited to the GP areas did not induce a noticeable change in wave dynamics. The octopus hypothesis-based model of the GP and nerve exhibited AF inducibility at higher ACh concentrations. In conclusion, a 3D in silico model of the GP and parasympathetic nerve based on the octopus model exhibited higher AF inducibility with higher ACh concentrations. PMID:26807030

  19. Draft Genome Sequence of the Deinococcus-Thermus Bacterium Meiothermus ruber Strain A

    PubMed Central

    Thiel, Vera; Tomsho, Lynn P.; Burhans, Richard; Gay, Scott E.; Schuster, Stephan C.; Ward, David M.

    2015-01-01

    The draft genome sequence of the Deinococcus-Thermus group bacterium Meiothermus ruber strain A, isolated from a cyanobacterial enrichment culture obtained from Octopus Spring (Yellowstone National Park, WY), comprises 2,968,099 bp in 170 contigs. It is predicted to contain 2,895 protein-coding genes, 44 tRNA-coding genes, and 2 rRNA operons. PMID:25814606

  20. Osmotic/ionic status of body fluids in the euryhaline cephalopod suggest possible parallel evolution of osmoregulation.

    PubMed

    Sakamoto, Tatsuya; Ogawa, Satoshi; Nishiyama, Yudai; Akada, Chiaki; Takahashi, Hideya; Watanabe, Taro; Minakata, Hiroyuki; Sakamoto, Hirotaka

    2015-01-01

    Acclimation from marine to dilute environments constitutes among the dramatic evolutionary transitions in the history of life. Such adaptations have evolved in multiple lineages, but studies of the blood/hemolymph homeostasis mechanisms are limited to those using evolutionarily advanced Deuterostome (chordates) and Ecdysozoa (crustaceans). Here, we examined hemolymph homeostasis in the advanced Lophotrochozoa/mollusc, the other unexplored taxa, and its possible regulation by the vasopressin/oxytocin superfamily peptides known to be implicated in fluid homeostasis in Chordata and Arthropoda. The hemolymph osmotic and ionic status in the euryhaline cephalopod (Octopus ocellatus) following transfer from 30-ppt normal seawater to 20 ppt salinity indicate hyperosmo- and hyperionoregulatory abilities for more than 1 week, as in crustaceans and teleost fish. While ventilation frequency decreased by 1 day, Na(+)/K(+)-ATPase activity, which has been generally implicated in ion transport, was induced in two of the eight posterior gills after 1 week. In addition, the octopuses were intravenously injected with 1 or 100 ng/g octopressin or cephalotocin, which are Octopus vasopressin/oxytocin orthologs. After 1 day, octopressin, but not cephalotocin, decreased the hemolymph osmolality and Ca concentrations, as well as urinary Na concentrations. These data provide evidence for possible parallel evolution in hyperionoregulatory mechanisms and coordination by conserved peptides. PMID:26403952

  1. Locomotion by Abdopus aculeatus (Cephalopoda: Octopodidae): walking the line between primary and secondary defenses.

    PubMed

    Huffard, Christine L

    2006-10-01

    Speeds and variation in body form during crawling, bipedal walking, swimming and jetting by the shallow-water octopus Abdopus aculeatus were compared to explore possible interactions between defense behaviors and biomechanics of these multi-limbed organisms. General body postures and patterns were more complex and varied during the slow mode of crawling than during fast escape maneuvers such as swimming and jetting. These results may reflect a trade-off between predator deception and speed, or simply a need to reduce drag during jet-propelled locomotion. Octopuses swam faster when dorsoventrally compressed, a form that may generate lift, than when swimming in the head-raised posture. Bipedal locomotion proceeded as fast as swimming and can be considered a form of fast escape (secondary defense) that also incorporates elements of crypsis and polyphenism (primary defenses). Body postures during walking suggested the use of both static and dynamic stability. Absolute speed was not correlated with body mass in any mode. Based on these findings the implications for defense behaviors such as escape from predation, aggression, and 'flatfish mimicry' performed by A. aculeatus and other octopuses are discussed.

  2. Osmotic/ionic status of body fluids in the euryhaline cephalopod suggest possible parallel evolution of osmoregulation

    PubMed Central

    Sakamoto, Tatsuya; Ogawa, Satoshi; Nishiyama, Yudai; Akada, Chiaki; Takahashi, Hideya; Watanabe, Taro; Minakata, Hiroyuki; Sakamoto, Hirotaka

    2015-01-01

    Acclimation from marine to dilute environments constitutes among the dramatic evolutionary transitions in the history of life. Such adaptations have evolved in multiple lineages, but studies of the blood/hemolymph homeostasis mechanisms are limited to those using evolutionarily advanced Deuterostome (chordates) and Ecdysozoa (crustaceans). Here, we examined hemolymph homeostasis in the advanced Lophotrochozoa/mollusc, the other unexplored taxa, and its possible regulation by the vasopressin/oxytocin superfamily peptides known to be implicated in fluid homeostasis in Chordata and Arthropoda. The hemolymph osmotic and ionic status in the euryhaline cephalopod (Octopus ocellatus) following transfer from 30-ppt normal seawater to 20 ppt salinity indicate hyperosmo- and hyperionoregulatory abilities for more than 1 week, as in crustaceans and teleost fish. While ventilation frequency decreased by 1 day, Na+/K+-ATPase activity, which has been generally implicated in ion transport, was induced in two of the eight posterior gills after 1 week. In addition, the octopuses were intravenously injected with 1 or 100 ng/g octopressin or cephalotocin, which are Octopus vasopressin/oxytocin orthologs. After 1 day, octopressin, but not cephalotocin, decreased the hemolymph osmolality and Ca concentrations, as well as urinary Na concentrations. These data provide evidence for possible parallel evolution in hyperionoregulatory mechanisms and coordination by conserved peptides. PMID:26403952

  3. Diverse Thermus species inhabit a single hot spring microbial mat

    NASA Technical Reports Server (NTRS)

    Nold, S. C.; Ward, D. M.

    1995-01-01

    Through an effort to characterize aerobic chemoorganotrophic bacteria in the Octopus Spring cyano-bacterial mat community, we cultivated four Thermus isolates with unique 16S rRNA sequences. Isolates clustered within existing Thermus clades, including those containing Thermus ruber, Thermus aquaticus, and a subgroup closely related to T. aquaticus. One Octopus Spring isolate is nearly identical (99.9% similar) to isolates from Iceland, and two others are closely related to a T. ruber isolated from Russia. Octopus Spring isolates similar to T. aquaticus and T. ruber exhibited optimal growth rates at high (65-70 degrees C) and low (50 degrees C) temperatures, respectively, with the most abundant species best adapted to the temperature of the habitat (50-55 degrees C). Our results display a diversity of Thermus genotypes defined by 16S rRNA within one hot spring microbial community. We suggest that specialization to temperature and perhaps other local environmental features controls the abundance of Thermus populations.

  4. Molecular phylogenetic analysis of the coccidian cephalopod parasites Aggregata octopiana and Aggregata eberthi (Apicomplexa: Aggregatidae) from the NE Atlantic coast using 18S rRNA sequences.

    PubMed

    Castellanos-Martínez, Sheila; Pérez-Losada, Marcos; Gestal, Camino

    2013-08-01

    The coccidia genus Aggregata is responsible for intestinal coccidiosis in wild and cultivated cephalopods. Two coccidia species, Aggregata octopiana, (infecting the common octopus Octopus vulgaris), and A. eberthi, (infecting the cuttlefish Sepia officinalis), are identified in European waters. Extensive investigation of their morphology resulted in a redescription of A. octopiana in octopuses from the NE Atlantic Coast (NW Spain) thus clarifying confusing descriptions recorded in the past. The present study sequenced the 18S rRNA gene in A. octopiana and A. eberthi from the NE Atlantic coast in order to assess their taxonomic and phylogenetic status. Phylogenetic analyses revealed conspecific genetic differences (2.5%) in 18S rRNA sequences between A. eberthi from the Ria of Vigo (NW Spain) and the Adriatic Sea. Larger congeneric differences (15.9%) were observed between A. octopiana samples from the same two areas, which suggest the existence of two species. Based on previous morphological evidence, host specificity data, and new molecular phylogenetic analyses, we suggest that A. octopiana from the Ria of Vigo is the valid type species.

  5. Interspecific and geographical variations of trace metal concentrations in cephalopods from Tunisian waters.

    PubMed

    Rjeibi, Moncef; Metian, Marc; Hajji, Tarek; Guyot, Thierry; Ben Chaouacha-Chékir, Rafika; Bustamante, Paco

    2014-06-01

    The concentrations of six metals (Ag, Cd, Cu, Hg, Pb, and Zn) were investigated and compared in three tissues (arms, digestive gland, and mantle) of three cephalopod species from the Tunisian waters: the common octopus (Octopus vulgaris), the common cuttlefish (Sepia officinalis), and the European squid (Loligo vulgaris). Whatever the species or the sites, the digestive gland displayed the highest concentrations of Ag, Cd, Cu, Pb, and Zn, highlighting its major role in their bioaccumulation and detoxification. This is also true for Hg but only for the digestive gland of O. vulgaris. Muscle from the arms and the mantle contained thus relatively low trace metal concentrations except for Hg in L. vulgaris and S. officinalis. Geographic comparison of metal concentrations in Tunisian cephalopods from three locations indicates that higher concentrations of Ag, Pb, and Hg were observed in cephalopods from northern and eastern coasts, whereas the highest Cd levels were detected in the southeastern, reflecting different conditions of exposure. Comparing the trace element concentrations between species, Ag, Cd, Cu, Hg, and Zn concentrations were the highest in the digestive gland of octopuses. This may be related to the differences in ecological features and swimming behavior among different cephalopod species. Effects of length and sex on metal levels were also considered, indicating a limited influence of sex on metal concentration. PMID:24562415

  6. Seasonal survey of contaminants (Cd and Hg) and micronutrients (Cu and Zn) in edible tissues of cephalopods from Tunisia: assessment of risk and nutritional benefits.

    PubMed

    Rjeibi, Moncef; Metian, Marc; Hajji, Tarek; Guyot, Thierry; Ben Chaouacha-Chekir, Rafika; Bustamante, Paco

    2015-01-01

    Concentrations of cadmium (Cd), copper (Cu), mercury (Hg), and zinc (Zn) were determined by atomic absorption spectrophotometry in the muscle tissues (arms and mantle) of 3 commercial cephalopods (Loligo vulgaris, Octopus vulgaris, and Sepia officinalis) caught in 3 different Tunisian coastal regions. The highest concentrations found correspond to the essential elements Cu and Zn. Octopuses and cuttlefish showed the highest levels of those elements whereas squid presented with significantly higher values of Hg in both muscular tissues. This may be related to different feeding behavior and detoxification processes among benthic and pelagic cephalopods. Variation of element concentrations between seasons was different between species and seemed to be mostly dependent on the sampling site. From a public health standpoint, average concentrations of Cd, Cu, Hg, and Zn measured in edible tissues of cephalopods from this study did not reveal, in general, any risk for consumers. The estimated target hazard quotients for Cd and Hg for consumers of the selected species were below 1 and within the safety range for human health. Moreover, their consumption could provide in an important contribution to the daily dietary intake of Cu for the Tunisian population, especially regarding the consumption of octopus and cuttlefish muscles. PMID:25427969

  7. Polymer brushes in explicit poor solvents studied using a new variant of the bond fluctuation model

    NASA Astrophysics Data System (ADS)

    Jentzsch, Christoph; Sommer, Jens-Uwe

    2014-09-01

    Using a variant of the Bond Fluctuation Model which improves its parallel efficiency in particular running on graphic cards we perform large scale simulations of polymer brushes in poor explicit solvent. Grafting density, solvent quality, and chain length are varied. Different morphological structures in particular octopus micelles are observed for low grafting densities. We reconsider the theoretical model for octopus micelles proposed by Williams using scaling arguments with the relevant scaling variable being σ/σc, and with the characteristic grafting density given by σc ˜ N-4/3. We find that octopus micelles only grow laterally, but not in height and we propose an extension of the model by assuming a cylindrical shape instead of a spherical geometry for the micelle-core. We show that the scaling variable σ/σc can be applied to master plots for the averaged height of the brush, the size of the micelles, and the number of chains per micelle. The exponents in the corresponding power law relations for the grafting density and chain length are in agreement with the model for flat cylindrical micelles. We also investigate the surface roughness and find that polymer brushes in explicit poor solvent at grafting densities higher than the stretching transition are flat and surface rippling can only be observed close to the stretching transition.

  8. Advantages and limitations of the spatially adaptive program SAPRO in clinical perimetry.

    PubMed

    Fankhauser, F; Funkhouser, A; Kwasniewska, S

    1986-05-01

    The SAPRO program devised for the OCTOPUS 201 automated perimeter, consists of a number of program components. It is designed to be used on the Octopus 201 computer. In its measurement mode, it employs an algorithm which achieves high speed and efficiency. This is made possible by a threshold bracketing strategy which is simpler than the normal OCTOPUS bracketing. Moreover, three grids with test location distributions of increasing resolution are superimposed in succession on the whole or on part of the visual field to be analyzed. Out of the distribution of test locations, only those which fulfill a number of criteria are actually utilized. These criteria must be given and are adaptable to any given clinical problem. As a result, despite the high spatial resolution achieved, only a fraction of the test locations are utilized using SAPRO as compared with a program using a fixed pattern of test locations. The algorithm is thus able to imitate human intelligence, which tends to concentrate stimuli at places which appear to be relevant for the solution of a problem. The results of program SAPRO are disturbed by short- and long-term fluctuations. Their validity is limited, in a manner similar to that encountered in any other threshold determination procedure. A number of printout modes is available which are oriented towards an optimal understanding of the information contained in various examinations. These principles will be illustrated by one case of inactive disseminated chorioretinitis. PMID:3755124

  9. Locomotion by Abdopus aculeatus (Cephalopoda: Octopodidae): walking the line between primary and secondary defenses.

    PubMed

    Huffard, Christine L

    2006-10-01

    Speeds and variation in body form during crawling, bipedal walking, swimming and jetting by the shallow-water octopus Abdopus aculeatus were compared to explore possible interactions between defense behaviors and biomechanics of these multi-limbed organisms. General body postures and patterns were more complex and varied during the slow mode of crawling than during fast escape maneuvers such as swimming and jetting. These results may reflect a trade-off between predator deception and speed, or simply a need to reduce drag during jet-propelled locomotion. Octopuses swam faster when dorsoventrally compressed, a form that may generate lift, than when swimming in the head-raised posture. Bipedal locomotion proceeded as fast as swimming and can be considered a form of fast escape (secondary defense) that also incorporates elements of crypsis and polyphenism (primary defenses). Body postures during walking suggested the use of both static and dynamic stability. Absolute speed was not correlated with body mass in any mode. Based on these findings the implications for defense behaviors such as escape from predation, aggression, and 'flatfish mimicry' performed by A. aculeatus and other octopuses are discussed. PMID:16985187

  10. Fate of Immediate Methane Precursors in Low-Sulfate, Hot-Spring Algal-Bacterial Mats

    PubMed Central

    Sandbeck, Kenneth A.; Ward, David M.

    1981-01-01

    The fates of acetate and carbon dioxide were examined in several experiments designed to indicate their relative contributions to methane production at various temperatures in two low-sulfate, hot-spring algal-bacterial mats. [2-14C]acetate was predominantly incorporated into cell material, although some 14CH4 and 14CO2 was produced. Acetate incorporation was reduced by dark incubation in short-term experiments and severely depressed by a 2-day preincubation in darkness. Autoradiograms showed that acetate was incorporated by long filaments resembling phototrophic microorganisms of the mat communities. [3H]acetate was not converted to C3H4 in samples from Octopus Spring collected at the optimum temperature for methanogenesis. NaH14CO3 was readily converted to 14CH4 at temperatures at which methanogenesis was active in both mats. Comparisons of the specific activities of methane and carbon dioxide suggested that of the methane produced, 80 ± 6% in Octopus Spring and 71 ± 21% in Wiegert Channel were derived from carbon dioxide. Addition of acetate to 1 mM did not reduce the relative importance of carbon dioxide as a methane precursor in samples from Octopus Spring. Experiments with pure cultures of Methanobacterium thermoautotrophicum suggested that the measured ratio of specific activities might underestimate the true contribution of carbon dioxide in methanogenesis. Images PMID:16345736

  11. Polymer brushes in explicit poor solvents studied using a new variant of the bond fluctuation model.

    PubMed

    Jentzsch, Christoph; Sommer, Jens-Uwe

    2014-09-14

    Using a variant of the Bond Fluctuation Model which improves its parallel efficiency in particular running on graphic cards we perform large scale simulations of polymer brushes in poor explicit solvent. Grafting density, solvent quality, and chain length are varied. Different morphological structures in particular octopus micelles are observed for low grafting densities. We reconsider the theoretical model for octopus micelles proposed by Williams using scaling arguments with the relevant scaling variable being σ/σ(c), and with the characteristic grafting density given by σ(c) ~ N(-4/3). We find that octopus micelles only grow laterally, but not in height and we propose an extension of the model by assuming a cylindrical shape instead of a spherical geometry for the micelle-core. We show that the scaling variable σ/σ(c) can be applied to master plots for the averaged height of the brush, the size of the micelles, and the number of chains per micelle. The exponents in the corresponding power law relations for the grafting density and chain length are in agreement with the model for flat cylindrical micelles. We also investigate the surface roughness and find that polymer brushes in explicit poor solvent at grafting densities higher than the stretching transition are flat and surface rippling can only be observed close to the stretching transition. PMID:25217952

  12. CLARET user's manual: Mainframe Logs. Revision 1

    SciTech Connect

    Frobose, R.H.

    1984-11-12

    CLARET (Computer Logging and RETrieval) is a stand-alone PDP 11/23 system that can support 16 terminals. It provides a forms-oriented front end by which operators enter online activity logs for the Lawrence Livermore National Laboratory's OCTOPUS computer network. The logs are stored on the PDP 11/23 disks for later retrieval, and hardcopy reports are generated both automatically and upon request. Online viewing of the current logs is provided to management. As each day's logs are completed, the information is automatically sent to a CRAY and included in an online database system. The terminal used for the CLARET system is a dual-port Hewlett Packard 2626 terminal that can be used as either the CLARET logging station or as an independent OCTOPUS terminal. Because this is a stand-alone system, it does not depend on the availability of the OCTOPUS network to run and, in the event of a power failure, can be brought up independently.

  13. Seasonal survey of contaminants (Cd and Hg) and micronutrients (Cu and Zn) in edible tissues of cephalopods from Tunisia: assessment of risk and nutritional benefits.

    PubMed

    Rjeibi, Moncef; Metian, Marc; Hajji, Tarek; Guyot, Thierry; Ben Chaouacha-Chekir, Rafika; Bustamante, Paco

    2015-01-01

    Concentrations of cadmium (Cd), copper (Cu), mercury (Hg), and zinc (Zn) were determined by atomic absorption spectrophotometry in the muscle tissues (arms and mantle) of 3 commercial cephalopods (Loligo vulgaris, Octopus vulgaris, and Sepia officinalis) caught in 3 different Tunisian coastal regions. The highest concentrations found correspond to the essential elements Cu and Zn. Octopuses and cuttlefish showed the highest levels of those elements whereas squid presented with significantly higher values of Hg in both muscular tissues. This may be related to different feeding behavior and detoxification processes among benthic and pelagic cephalopods. Variation of element concentrations between seasons was different between species and seemed to be mostly dependent on the sampling site. From a public health standpoint, average concentrations of Cd, Cu, Hg, and Zn measured in edible tissues of cephalopods from this study did not reveal, in general, any risk for consumers. The estimated target hazard quotients for Cd and Hg for consumers of the selected species were below 1 and within the safety range for human health. Moreover, their consumption could provide in an important contribution to the daily dietary intake of Cu for the Tunisian population, especially regarding the consumption of octopus and cuttlefish muscles.

  14. Risk assessment of methyl-mercury intake through cephalopods consumption in Portugal.

    PubMed

    Cardoso, C; Lourenço, H; Afonso, C; Nunes, M L

    2012-01-01

    The intake of methyl-mercury (methyl-Hg) through the consumption of three common cephalopod species, cuttlefish (Sepia officinalis), squid (Loligo vulgaris) and octopus (Octopus vulgaris), in Portugal as well as the associated probability of exceeding the provisional tolerable weekly intake (PTWI) were estimated by combining methyl-Hg contamination levels in these three cephalopods with constructed consumption scenarios and with a hypothesised consumption distribution for the general Portuguese population. It was found that squid presents no serious health concern with respect to methyl-Hg, but cuttlefish and octopus consumption should not exceed two 150 g meals per week. Moreover, the methyl-Hg risk assessment for Portuguese consumers showed no risk concerning the observed cephalopods consumption levels. However, besides methyl-Hg, other toxic metals present in cephalopods, such as cadmium, may be a serious health concern and the methyl-Hg risk can be compounded by the risk of other foods containing significant methyl-Hg levels, especially long-lived sea predators. Accordingly, a cautionary note must be attached to advised maximum consumptions, which may be revised by future studies. Tail estimation (TE) estimator was more accurate for lower probabilities, rendering accurate risk estimations different from zero. However, for higher probabilities, the much simpler plug-in (PI) estimator could be applied. Additionally, limitations of a deterministic approach were identified.

  15. Interspecific and geographical variations of trace metal concentrations in cephalopods from Tunisian waters.

    PubMed

    Rjeibi, Moncef; Metian, Marc; Hajji, Tarek; Guyot, Thierry; Ben Chaouacha-Chékir, Rafika; Bustamante, Paco

    2014-06-01

    The concentrations of six metals (Ag, Cd, Cu, Hg, Pb, and Zn) were investigated and compared in three tissues (arms, digestive gland, and mantle) of three cephalopod species from the Tunisian waters: the common octopus (Octopus vulgaris), the common cuttlefish (Sepia officinalis), and the European squid (Loligo vulgaris). Whatever the species or the sites, the digestive gland displayed the highest concentrations of Ag, Cd, Cu, Pb, and Zn, highlighting its major role in their bioaccumulation and detoxification. This is also true for Hg but only for the digestive gland of O. vulgaris. Muscle from the arms and the mantle contained thus relatively low trace metal concentrations except for Hg in L. vulgaris and S. officinalis. Geographic comparison of metal concentrations in Tunisian cephalopods from three locations indicates that higher concentrations of Ag, Pb, and Hg were observed in cephalopods from northern and eastern coasts, whereas the highest Cd levels were detected in the southeastern, reflecting different conditions of exposure. Comparing the trace element concentrations between species, Ag, Cd, Cu, Hg, and Zn concentrations were the highest in the digestive gland of octopuses. This may be related to the differences in ecological features and swimming behavior among different cephalopod species. Effects of length and sex on metal levels were also considered, indicating a limited influence of sex on metal concentration.

  16. Abalone (Haliotis tuberculata) hemocyanin type 1 (HtH1). Organization of the approximately 400 kDa subunit, and amino acid sequence of its functional units f, g and h.

    PubMed

    Keller, H; Lieb Bp6; Altenhein, B; Gebauer, D; Richter, S; Stricker, S; Markl, J

    1999-08-01

    We have identified two separate hemocyanin types (HtH1 and HtH2) in the European abalone Haliotis tuberculata. HtH1/HtH2 hybrid molecules were not found. By selective dissociation of HtH2 we isolated HtH1 which, as revealed by electron microscopy and SDS/PAGE, is present as didecamers of a approximately 400 kDa subunit. Immunologically, HtH1 and HtH2 correspond to keyhole limpet hemocyanin (KLH)1 and KLH2, respectively, the two well-studied hemocyanin types of the closely related marine gastropod Megathura crenulata. On the basis of limited proteolytic cleavage, two-dimensional immunoelectrophoresis, SDS/PAGE and N-terminal sequencing, we identified eight different 40-60 kDa functional units in HtH1, termed HtH1-a to HtH1-h, and determined their linear arrangement within the elongated subunit. From Haliotis mantle tissue, rich in hemocyanin-producing pore cells, we isolated mRNA and constructed a cDNA library. By expression screening with HtH-specific rabbit antibodies, a cDNA clone was isolated and sequenced which codes for the three C-terminal functional units f, g and h of HtH1. Their sequences were aligned to those available from other molluscs, notably to functional unit f and functional unit g from the cephalopod Octopus dofleini. HtH1-f, which is the first sequenced functional unit of type f from a gastropod hemocyanin, corresponds to functional unit f from Octopus. Also functional unit g from Haliotis and Octopus correspond to each other. HtH1-h is a gastropod hemocyanin functional unit type which is absent in cephalopods and has not been sequenced previously. It exhibits a unique tail extension of approximately 95 amino acids, which is lacking in functional units a to g and aligns with a published peptide sequence of 48 amino acids from functional unit h of Helix pomatia hemocyanin. The new Haliotis sequences are discussed with respect to their counterparts in Octopus, the 15 A three-dimensional reconstruction of the KLH1 didecamer from electron

  17. Oct-GnRH, the first protostomian gonadotropin-releasing hormone-like peptide and a critical mini-review of the presence of vertebrate sex steroids in molluscs.

    PubMed

    Minakata, Hiroyuki; Tsutsui, Kazuyoshi

    2016-02-01

    In protostome and deuterosome invertebrates, neurosecretory cells play major roles in the endocrine system. The optic glands of cephalopods are indicators of sexual maturation. In mature octopuses, optic glands enlarge and secrete a gonadotropic hormone. A peptide with structural features similar to that of vertebrate gonadotropin-releasing hormone (GnRH) was isolated from the octopus, Octopus vulgaris, and was named oct-GnRH. The discovery of oct-GnRH has triggered structural determinations and predictions of other mollusc GnRH-like peptides in biochemical and in silico studies. Interestingly, cephalopods studied so far are characterized by a single molecular form of oct-GnRH with a C-terminal -Pro-Gly-NH2 sequence, which is critical for gonadotropin-releasing activity in vertebrates. Other molluscan GnRH-like peptides lack the C-terminal -Pro-Gly-NH2 sequence but have -X-NH2 or -Pro-Gly although all protostome GnRH-like peptides have yet to be sequenced. In marine molluscs, relationships between GnRH-like peptides and sex steroids have been studied to verify the hypothesis that molluscs have vertebrate-type sex steroid system. However, it is currently questionable whether such sex steroids are present and whether they play endogenous roles in the reproductive system of molluscs. Because molluscs uptake and store steroids from the environment and fishes release sex steroids into the external environment, it is impossible to rule out the contamination of vertebrate sex steroids in molluscs. The function of key enzymes of steroidogenesis within molluscs remains unclear. Thus, evidence to deny the existence of the vertebrate-type sex steroid system in molluscs has been accumulated. The elucidation of substances, which regulate the maturation and maintenance of gonads and other reproductive functions in molluscs will require rigorous and progressive scientific study.

  18. Resonance raman spectroscopy of an ultraviolet-sensitive insect rhodopsin

    SciTech Connect

    Pande, C.; Deng, H.; Rath, P.; Callender, R.H.; Schwemer, J.

    1987-11-17

    The authors present the first visual pigment resonance Raman spectra from the UV-sensitive eyes of an insect, Ascalaphus macaronius (owlfly). This pigment contains 11-cis-retinal as the chromophore. Raman data have been obtained for the acid metarhodopsin at 10/sup 0/C in both H/sub 2/O and D/sub 2/O. The C=N stretching mode at 1660 cm/sup -1/ in H/sub 2/O shifts to 1631 cm/sup -1/ upon deuteriation of the sample, clearly showing a protonated Schiff base linkage between the chromophore and the protein. The structure-sensitive fingerprint region shows similarities to the all-trans-protonated Schiff base of model retinal chromophores, as well as to the octopus acid metarhodopsin and bovine metarhodopsin I. Although spectra measured at -100/sup 0/C with 406.7-nm excitation, to enhance scattering from rhodopsin (lambda/sub max/ 345 nm), contain a significant contribution from a small amount of contaminants (cytochrome(s) and/or accessory pigment) in the sample, the C=N stretch at 1664 cm/sup -1/ suggests a protonated Schiff base linkage between the chromophore and the protein in rhodopsin as well. For comparison, this mode also appears at approx. 1660 cm/sup -1/ in both the vertebrate (bovine) and the invertebrate (octopus) rhodopsins. These data are particularly interesting since the absorption maximum of 345 nm for rhodopsin might be expected to originate from an unprotonated Schiff base linkage. That the Schiff base linkage in the owlfly rhodopsin, like in bovine and in octopus, is protonated suggests that a charged chromophore is essential to visual transduction.

  19. Subunit organization of the abalone Haliotis tuberculata hemocyanin type 2 (HtH2), and the cDNA sequence encoding its functional units d, e, f, g and h.

    PubMed

    Lieb, B; Altenhein, B; Lehnert, R; Gebauer, W; Markl, J

    1999-10-01

    We have developed a HPLC procedure to isolate the two different hemocyanin types (HtH1 and HtH2) of the European abalone Haliotis tuberculata. On the basis of limited proteolytic cleavage, two-dimensional immunoelectrophoresis, PAGE, N-terminal protein sequencing and cDNA sequencing, we have identified eight different 40-60-kDa functional units (FUs) in HtH2, termed HtH2-a to HtH2-h, and determined their linear arrangement within the elongated 400-kDa subunit. From a Haliotis cDNA library, we have isolated and sequenced a cDNA clone which encodes the five C-terminal FUs d, e, f, g and h of HtH2. As shown by multiple sequence alignments, defg of HtH2 correspond structurally to defg from Octopus dofleini hemocyanin. HtH2-e is the first FU of a gastropod hemocyanin to be sequenced. The new Haliotis hemocyanin sequences are compared to their counterparts in Octopus, Helix pomatia and HtH1 (from the latter, the sequences of FU-f, FU-g and FU-h have recently been determined) and discussed in relation to the recent 2.3 A X-ray structure of FU-g from Octopus hemocyanin and the 15 A three-dimensional reconstruction of the Megathura crenulata hemocyanin didecamer from electron micrographs. This data allows, for the first time, an insight into the evolution of the two functionally different hemocyanin isoforms found in marine gastropods. It appears that they evolved several hundred million years ago within the Prosobranchia, after separation of the latter from the branch leading to the Pulmonata. Moreover, as a structural explanation for the inefficiency of the type 1 hemocyanin to form multidecamers in vivo, the additional N-glycosylation sites in HtH1 compared to HtH2 are discussed. PMID:10491167

  20. Structures of two molluscan hemocyanin genes: significance for gene evolution.

    PubMed

    Lieb, B; Altenhein, B; Markl, J; Vincent, A; van Olden, E; van Holde, K E; Miller, K I

    2001-04-10

    We present here the description of genes coding for molluscan hemocyanins. Two distantly related mollusks, Haliotis tuberculata and Octopus dofleini, were studied. The typical architecture of a molluscan hemocyanin subunit, which is a string of seven or eight globular functional units (FUs, designated a to h, about 50 kDa each), is reflected by the gene organization: a series of eight structurally related coding regions in Haliotis, corresponding to FU-a to FU-h, with seven highly variable linker introns of 174 to 3,198 bp length (all in phase 1). In Octopus seven coding regions (FU-a to FU-g) are found, separated by phase 1 introns varying in length from 100 bp to 910 bp. Both genes exhibit typical signal (export) sequences, and in both cases these are interrupted by an additional intron. Each gene also contains an intron between signal peptide and FU-a and in the 3' untranslated region. Of special relevance for evolutionary considerations are introns interrupting those regions that encode a discrete functional unit. We found that five of the eight FUs in Haliotis each are encoded by a single exon, whereas FU-f, FU-g, and FU-a are encoded by two, three and four exons, respectively. Similarly, in Octopus four of the FUs each correspond to an uninterrupted exon, whereas FU-b, FU-e, and FU-f each contain a single intron. Although the positioning of the introns between FUs is highly conserved in the two mollusks, the introns within FUs show no relationship either in location nor phase. It is proposed that the introns between FUs were generated as the eight-unit polypeptide evolved from a monomeric precursor, and that the internal introns have been added later. A hypothesis for evolution of the ring-like quaternary structure of molluscan hemocyanins is presented. PMID:11287637

  1. Structures of two molluscan hemocyanin genes: Significance for gene evolution

    PubMed Central

    Lieb, Bernhard; Altenhein, Benjamin; Markl, Jürgen; Vincent, Alexandra; van Olden, Erin; van Holde, Kensal E.; Miller, Karen I.

    2001-01-01

    We present here the description of genes coding for molluscan hemocyanins. Two distantly related mollusks, Haliotis tuberculata and Octopus dofleini, were studied. The typical architecture of a molluscan hemocyanin subunit, which is a string of seven or eight globular functional units (FUs, designated a to h, about 50 kDa each), is reflected by the gene organization: a series of eight structurally related coding regions in Haliotis, corresponding to FU-a to FU-h, with seven highly variable linker introns of 174 to 3,198 bp length (all in phase 1). In Octopus seven coding regions (FU-a to FU-g) are found, separated by phase 1 introns varying in length from 100 bp to 910 bp. Both genes exhibit typical signal (export) sequences, and in both cases these are interrupted by an additional intron. Each gene also contains an intron between signal peptide and FU-a and in the 3′ untranslated region. Of special relevance for evolutionary considerations are introns interrupting those regions that encode a discrete functional unit. We found that five of the eight FUs in Haliotis each are encoded by a single exon, whereas FU-f, FU-g, and FU-a are encoded by two, three and four exons, respectively. Similarly, in Octopus four of the FUs each correspond to an uninterrupted exon, whereas FU-b, FU-e, and FU-f each contain a single intron. Although the positioning of the introns between FUs is highly conserved in the two mollusks, the introns within FUs show no relationship either in location nor phase. It is proposed that the introns between FUs were generated as the eight-unit polypeptide evolved from a monomeric precursor, and that the internal introns have been added later. A hypothesis for evolution of the ring-like quaternary structure of molluscan hemocyanins is presented. PMID:11287637

  2. Heavy metals in fish from the Aleutians: interspecific and locational differences.

    PubMed

    Burger, Joanna; Gochfeld, Michael; Jeitner, Christian; Pittfield, Taryn; Donio, Mark

    2014-05-01

    The objectives of this study were to examine levels of arsenic, cadmium, lead, mercury and selenium in edible tissue of seven species of marine fish collected from several Aleutian islands (in 2004) to determine: (1) interspecific differences, (2) locational differences (among Aleutian Islands), (3) size-related differences in any metal levels within a species, and (4) potential risk to the fish or to predators on the fish, including humans. We also compared metals levels to those of three other fish species previously examined in detail, as well as examining metals in the edible tissue of octopus (Octopus dofleini). Octopus did not have the highest levels of any metal. There were significant interspecific differences in all metal levels among the fish species, although the differences were less than an order of magnitude, except for arsenic (mean of 19,500 ppb in Flathead sole, Hippoglossoides elassodon). Significant intraisland variation occurred among the four sites on Amchitka, but there was not a consistent pattern. There were significant interisland differences for some metals and species. Mercury levels increased significantly with size for several species; lead increased significantly for only one fish species; and cadmium and selenium decreased significantly with size for halibut (Hippoglossus stenolepis). The Alaskan Department of Health and Social Services supports unrestricted consumption of most Alaskan fish species for all people, including pregnant women. Most mean metal concentrations were well below the levels known to adversely affect the fish themselves, or predators that consume them (including humans), except for mercury in three fish species (mean levels just below 0.3 ppm), and arsenic in two fish species. However, even at low mercury levels, people who consume fish almost daily will exceed guideline values from the Centers for Disease Control and the Environmental Protection Agency. PMID:24727640

  3. Oct-GnRH, the first protostomian gonadotropin-releasing hormone-like peptide and a critical mini-review of the presence of vertebrate sex steroids in molluscs.

    PubMed

    Minakata, Hiroyuki; Tsutsui, Kazuyoshi

    2016-02-01

    In protostome and deuterosome invertebrates, neurosecretory cells play major roles in the endocrine system. The optic glands of cephalopods are indicators of sexual maturation. In mature octopuses, optic glands enlarge and secrete a gonadotropic hormone. A peptide with structural features similar to that of vertebrate gonadotropin-releasing hormone (GnRH) was isolated from the octopus, Octopus vulgaris, and was named oct-GnRH. The discovery of oct-GnRH has triggered structural determinations and predictions of other mollusc GnRH-like peptides in biochemical and in silico studies. Interestingly, cephalopods studied so far are characterized by a single molecular form of oct-GnRH with a C-terminal -Pro-Gly-NH2 sequence, which is critical for gonadotropin-releasing activity in vertebrates. Other molluscan GnRH-like peptides lack the C-terminal -Pro-Gly-NH2 sequence but have -X-NH2 or -Pro-Gly although all protostome GnRH-like peptides have yet to be sequenced. In marine molluscs, relationships between GnRH-like peptides and sex steroids have been studied to verify the hypothesis that molluscs have vertebrate-type sex steroid system. However, it is currently questionable whether such sex steroids are present and whether they play endogenous roles in the reproductive system of molluscs. Because molluscs uptake and store steroids from the environment and fishes release sex steroids into the external environment, it is impossible to rule out the contamination of vertebrate sex steroids in molluscs. The function of key enzymes of steroidogenesis within molluscs remains unclear. Thus, evidence to deny the existence of the vertebrate-type sex steroid system in molluscs has been accumulated. The elucidation of substances, which regulate the maturation and maintenance of gonads and other reproductive functions in molluscs will require rigorous and progressive scientific study. PMID:26319132

  4. Heavy metals in fish from the Aleutians: interspecific and locational differences.

    PubMed

    Burger, Joanna; Gochfeld, Michael; Jeitner, Christian; Pittfield, Taryn; Donio, Mark

    2014-05-01

    The objectives of this study were to examine levels of arsenic, cadmium, lead, mercury and selenium in edible tissue of seven species of marine fish collected from several Aleutian islands (in 2004) to determine: (1) interspecific differences, (2) locational differences (among Aleutian Islands), (3) size-related differences in any metal levels within a species, and (4) potential risk to the fish or to predators on the fish, including humans. We also compared metals levels to those of three other fish species previously examined in detail, as well as examining metals in the edible tissue of octopus (Octopus dofleini). Octopus did not have the highest levels of any metal. There were significant interspecific differences in all metal levels among the fish species, although the differences were less than an order of magnitude, except for arsenic (mean of 19,500 ppb in Flathead sole, Hippoglossoides elassodon). Significant intraisland variation occurred among the four sites on Amchitka, but there was not a consistent pattern. There were significant interisland differences for some metals and species. Mercury levels increased significantly with size for several species; lead increased significantly for only one fish species; and cadmium and selenium decreased significantly with size for halibut (Hippoglossus stenolepis). The Alaskan Department of Health and Social Services supports unrestricted consumption of most Alaskan fish species for all people, including pregnant women. Most mean metal concentrations were well below the levels known to adversely affect the fish themselves, or predators that consume them (including humans), except for mercury in three fish species (mean levels just below 0.3 ppm), and arsenic in two fish species. However, even at low mercury levels, people who consume fish almost daily will exceed guideline values from the Centers for Disease Control and the Environmental Protection Agency.

  5. Physiological adaptation of an Antarctic Na+/K+-ATPase to the cold

    PubMed Central

    Galarza-Muñoz, Gaddiel; Soto-Morales, Sonia I.; Holmgren, Miguel; Rosenthal, Joshua J. C.

    2011-01-01

    SUMMARY Because enzymatic activity is strongly suppressed by the cold, polar poikilotherms face significant adaptive challenges. For example, at 0°C the catalytic activity of a typical enzyme from a temperate organism is reduced by more than 90%. Enzymes embedded in the plasma membrane, such as the Na+/K+-ATPase, may be even more susceptible to the cold because of thermal effects on the lipid bilayer. Accordingly, adaptive changes in response to the cold may include adjustments to the enzyme or the surrounding lipid environment, or synergistic changes to both. To assess the contribution of the enzyme itself, we cloned orthologous Na+/K+-ATPase α-subunits from an Antarctic (Pareledone sp.; –1.8°C) and a temperate octopus (Octopus bimaculatus; ∼18°C), and compared their turnover rates and temperature sensitivities in a heterologous expression system. The primary sequences of the two pumps were found to be highly similar (97% identity), with most differences being conservative changes involving hydrophobic residues. The physiology of the pumps was studied using an electrophysiological approach in intact Xenopus oocytes. The voltage dependence of the pumps was equivalent. However, at room temperature the maximum turnover rate of the Antarctic pump was found to be 25% higher than that of the temperate pump. In addition, the Antarctic pump exhibited a lower temperature sensitivity, leading to significantly higher relative activity at lower temperatures. Orthologous Na+/K+ pumps were then isolated from two tropical and two Arctic octopus. The temperature sensitivities of these pumps closely matched those of the temperate and Antarctic pumps, respectively. Thus, reduced thermal sensitivity appears to be a common mechanism driving cold adaptation in the Na+/K+-ATPase. PMID:21653810

  6. Manipulability, force, and compliance analysis for planar continuum manipulators

    NASA Technical Reports Server (NTRS)

    Gravagne, Ian A.; Walker, Ian D.

    2002-01-01

    Continuum manipulators, inspired by the natural capabilities of elephant trunks and octopus tentacles, may find niche applications in areas like human-robot interaction, multiarm manipulation, and unknown environment exploration. However, their true capabilities will remain largely inaccessible without proper analytical tools to evaluate their unique properties. Ellipsoids have long served as one of the foremost analytical tools available to the robotics researcher, and the purpose of this paper is to first formulate, and then to examine, three types of ellipsoids for continuum robots: manipulability, force, and compliance.

  7. Cephalopod consciousness: behavioural evidence.

    PubMed

    Mather, Jennifer A

    2008-03-01

    Behavioural evidence suggests that cephalopod molluscs may have a form of primary consciousness. First, the linkage of brain to behaviour seen in lateralization, sleep and through a developmental context is similar to that of mammals and birds. Second, cephalopods, especially octopuses, are heavily dependent on learning in response to both visual and tactile cues, and may have domain generality and form simple concepts. Third, these animals are aware of their position, both within themselves and in larger space, including having a working memory of foraging areas in the recent past. Thus if using a 'global workspace' which evaluates memory input and focuses attention is the criterion, cephalopods appear to have primary consciousness.

  8. Time dependent modeling of non-LTE plasmas: Final report

    SciTech Connect

    Not Available

    1988-06-01

    During the period of performance of this contract Science Applications International Corporation (SAIC) has aided Lawrence Livermore National Laboratory (LLNL) in the development of an unclassified modeling tool for studying time evolution of high temperature ionizing and recombining plasmas. This report covers the numerical code developed, (D)ynamic (D)etailed (C)onfiguration (A)ccounting (DDCA), which was written to run on the National Magnetic Fusion Energy Computing Center (NMFECC) network as well as the classified Livermore Computer Center (OCTOPUS) network. DDCA is a One-Dimensional (1D) time dependent hydrodynamic model which makes use of the non-LTE detailed atomic physics ionization model DCA. 5 refs.

  9. [Metamorphosis of the uterus from Hippocrates to Ambroise Pare].

    PubMed

    Dasen, Véronique

    2002-01-01

    The treatise Des monstres et prodiges (1579, 1585) by Ambroise Paré includes a vignette depicting a monstrous embryo in the form of a human head surrounded by snakes. This picture belongs to the iconographic tradition relating to the Graeco-Roman mythology of sexuality and procreation. It derives from the belief in the womb's animal nature, illustrated on magic Graeco-Roman and Byzantine gemstones, where the uterus is shown in turn as a cupping vessel, a scarab-beetle, an octopus or the head of Gorgo.

  10. Tunable structural color in organisms and photonic materials for design of bioinspired materials

    NASA Astrophysics Data System (ADS)

    Fudouzi, Hiroshi

    2011-12-01

    In this paper, the key topics of tunable structural color in biology and material science are overviewed. Color in biology is considered for selected groups of tropical fish, octopus, squid and beetle. It is caused by nanoplates in iridophores and varies with their spacing, tilting angle and refractive index. These examples may provide valuable hints for the bioinspired design of photonic materials. 1D multilayer films and 3D colloidal crystals with tunable structural color are overviewed from the viewpoint of advanced materials. The tunability of structural color by swelling and strain is demonstrated on an example of opal composites.

  11. Molecular Dynamics Simulations of Liquid-Crystalline Dendritic Architectures

    NASA Astrophysics Data System (ADS)

    Bourgogne, C.; Bury, I.; Gehringer, L.; Zelcer, A.; Cukiernik, F.; Terazzi, E.; Donnio, B.; Guillon, D.

    We report here a few examples of the self-organization behaviour of some novel materials based on liquid-crystalline dendritic architectures. The original design of the molecules imposes the use of all-atomic methods to model correctly every intra- and intermolecular effects. The selected materials are octopus dendrimers with block anisotropic side-arms, segmented amphiphilic block codendrimers, multicore and star-shaped oligomers, and multi-functionalized manganese clusters. The molecular organization in lamellar or columnar phases occurs due to soft/rigid parts self-recognition, hydrogen-bonding networks or from the molecular shape intrinsically.

  12. Structural Evolution of Silicon Oxide Nanowires via Head-Growth Solid-Liquid-Solid Process

    NASA Astrophysics Data System (ADS)

    Hsu, Cheng-Hang; Chan, Shih-Yu; Chen, Chia-Fu

    2007-11-01

    In this paper, we propose a growth mechanism for silicon oxide nanowires (SiONWs) as a unique solid-liquid-solid process. SiONWs were synthesized in a furnace at 1000 °C and cooled at a high rate. Nickel and gold were introduced as catalysts to dissolve and precipitate the silicon oxide originally prepared by wet oxidation. The ratio of nickel to gold determined the precipitation rate and different “octopus-like” structures were formed. At a specific cooling rate, composition and amount of a catalyst, aligned silicon oxide nanowires with unattached ends were obtained.

  13. Development of a 3D immersive videogame to improve arm-postural coordination in patients with TBI

    PubMed Central

    2011-01-01

    Background Traumatic brain injury (TBI) disrupts the central and executive mechanisms of arm(s) and postural (trunk and legs) coordination. To address these issues, we developed a 3D immersive videogame-- Octopus. The game was developed using the basic principles of videogame design and previous experience of using videogames for rehabilitation of patients with acquired brain injuries. Unlike many other custom-designed virtual environments, Octopus included an actual gaming component with a system of multiple rewards, making the game challenging, competitive, motivating and fun. Effect of a short-term practice with the Octopus game on arm-postural coordination in patients with TBI was tested. Methods The game was developed using WorldViz Vizard software, integrated with the Qualysis system for motion analysis. Avatars of the participant's hands precisely reproducing the real-time kinematic patterns were synchronized with the simulated environment, presented in the first person 3D view on an 82-inch DLP screen. 13 individuals with mild-to-moderate manifestations of TBI participated in the study. While standing in front of the screen, the participants interacted with a computer-generated environment by popping bubbles blown by the Octopus. The bubbles followed a specific trajectory. Interception of the bubbles with the left or right hand avatar allowed flexible use of the postural segments for balance maintenance and arm transport. All participants practiced ten 90-s gaming trials during a single session, followed by a retention test. Arm-postural coordination was analysed using principal component analysis. Results As a result of the short-term practice, the participants improved in game performance, arm movement time, and precision. Improvements were achieved mostly by adapting efficient arm-postural coordination strategies. Of the 13 participants, 10 showed an immediate increase in arm forward reach and single-leg stance time. Conclusion These results support the

  14. Identification and distribution of gonadotropin-releasing hormone-like peptides in the brain of horseshoe crab Tachypleus tridentatus

    NASA Astrophysics Data System (ADS)

    Huang, Huiyang; Li, Linming; Ye, Haihui; Feng, Biyun; Li, Shaojing

    2013-03-01

    Gonadotropin-releasing hormone (GnRH) is a crucial peptide for the regulation of reproduction. Using immunological techniques, we investigated the presence of GnRH in horseshoe crab Tachypleus tridentatus. Octopus GnRH-like immunoreactivity, tunicate GnRH-like immunoreactivity, and lamprey GnRH-I-like immunoreactivity were detected in the neurons and fibers of the protocerebrum. However, no mammal GnRH-like immunoreactivity or lamprey GnRH-III-like immunoreactivity was observed. Our results suggest that a GnRH-like factor, an ancient peptide, existed in the brain of T. tridentatus and may be involved in the reproductive endocrine system.

  15. Personal Pervasive Environments: Practice and Experience

    PubMed Central

    Ballesteros, Francisco J.; Guardiola, Gorka; Soriano, Enrique

    2012-01-01

    In this paper we present our experience designing and developing two different systems to enable personal pervasive computing environments, Plan B and the Octopus. These systems were fully implemented and have been used on a daily basis for years. Both are based on synthetic (virtual) file system interfaces and provide mechanisms to adapt to changes in the context and reconfigure the system to support pervasive applications. We also present the main differences between them, focusing on architectural and reconfiguration aspects. Finally, we analyze the pitfalls and successes of both systems and review the lessons we learned while designing, developing, and using them. PMID:22969340

  16. Sale of street food in Latin America. The Mexican case: joy or jeopardy?

    PubMed

    Muñoz de Chávez, M; Chávez Villasana, A; Chávez Muñoz, M; Eichin Vuskovic, I

    2000-01-01

    Have you ever visited a public market in Mexico, Guatemala, Panama, Colombia, Venezuela, Peru or Brazil? Have you ever stopped to eat delicious Mayan-style pork tacos, turnovers filled with corn fungus or squash flower, octopus stuffed crepes, crab, cassava, 'alcapurrias' or grasshoppers with lime juice and chili, agave worms or a 'come back to life' seafood cocktail? If you have not, you have been missing a large part of the Mexican, Guatemalan, Panamanian, Colombian, Venezuelan, Peruvian and Brazilian folklore, taste, smell and color. And if you have visited these countries, it will be easier for you to understand the information in this chapter.

  17. Fast, high-resolution 3D dosimetry utilizing a novel optical-CT scanner incorporating tertiary telecentric collimation.

    PubMed

    Sakhalkar, H S; Oldham, M

    2008-01-01

    This study introduces a charge coupled device (CCD) area detector based optical-computed tomography (optical-CT) scanner for comprehensive verification of radiation dose distributions recorded in nonscattering radiochromic dosimeters. Defining characteristics include: (i) a very fast scanning time of approximately 5 min to acquire a complete three-dimensional (3D) dataset, (ii) improved image formation through the use of custom telecentric optics, which ensures accurate projection images and minimizes artifacts from scattered and stray-light sources, and (iii) high resolution (potentially 50 microm) isotropic 3D dose readout. The performance of the CCD scanner for 3D dose readout was evaluated by comparison with independent 3D readout from the single laser beam OCTOPUS-scanner for the same PRESAGE dosimeters. The OCTOPUS scanner was considered the "gold standard" technique in light of prior studies demonstrating its accuracy. Additional comparisons were made against calculated dose distributions from the ECLIPSE treatment-planning system. Dose readout for the following treatments were investigated: (i) a single rectangular beam irradiation to investigate small field and very steep dose gradient dosimetry away from edge effects, (ii) a 2-field open beam parallel-opposed irradiation to investigate dosimetry along steep dose gradients, and (iii) a 7-field intensity modulated radiation therapy (IMRT) irradiation to investigate dosimetry for complex treatment delivery involving modulation of fluence and for dosimetry along moderate dose gradients. Dose profiles, dose-difference plots, and gamma maps were employed to evaluate quantitative estimates of agreement between independently measured and calculated dose distributions. Results indicated that dose readout from the CCD scanner was in agreement with independent gold-standard readout from the OCTOPUS-scanner as well as the calculated ECLIPSE dose distribution for all treatments, except in regions within a few

  18. [Metamorphosis of the uterus from Hippocrates to Ambroise Pare].

    PubMed

    Dasen, Véronique

    2002-01-01

    The treatise Des monstres et prodiges (1579, 1585) by Ambroise Paré includes a vignette depicting a monstrous embryo in the form of a human head surrounded by snakes. This picture belongs to the iconographic tradition relating to the Graeco-Roman mythology of sexuality and procreation. It derives from the belief in the womb's animal nature, illustrated on magic Graeco-Roman and Byzantine gemstones, where the uterus is shown in turn as a cupping vessel, a scarab-beetle, an octopus or the head of Gorgo. PMID:12587402

  19. LINCS

    SciTech Connect

    Fletcher, J.G.

    1984-10-15

    LINCS - the Livermore Interactive Network Communications Structure (or Standard or System) - is a hierarchy of communication protocols designed at the Lawrence Livermore National Laboratory and used by the Laboratory's Octopus computing network and the extension of that network called Labnet. Since meaningful communication requires some degree of commonality between the sender's and the receiver's view of their environment, LINCS defines salient features of that view. The view conforms to an underlying philosophy about the nature of computing and computer-oriented communication, aspects of which are discussed here. Further information about LINCS and a more extensive list of references may be found in an earlier paper.

  20. Syntax and semantics of NLTSS Message tokens

    SciTech Connect

    Minton, J.; Donnelley, J.

    1980-04-24

    The basic unit of an NLTSS message is the Message token (or token). Groups of these tokens make up statements, and groups of statements make up a session. This report describes the current format and meaning of tokens, statements, and Sessions (as used by NLTSS servers). It is intended as a guideline for the prototype NLTSS File Server, Directory Server, Process Server, Account Server, and others. The final formats and meanings that will be published in a Network Standards document may differ. Most of the material in this report is gathered from strawman proposals and meetings between the Octopus Network and NLTSS groups.

  1. Electron-donor dopant, method of improving conductivity of polymers by doping therewith, and a polymer so treated

    SciTech Connect

    Liepins, R.; Aldissi, M.

    1988-07-05

    The electrically conductive material is described comprising a polymer with a conjugated backbone selected from the group consisting of polyacetylene, polypyrrone, and polyphenylquinoxaline, the polymer being electron-donor doped to a controlled degree with an agent derived from an electride dopant or a dopant derived from an alkalide both of which contain a trapping agent being selected from the group consisting of: a crown ether, 1,4,7,10,13,16-hexaoxacyclooctadecane, cryptand, methyl ether cyclodextrin, spherand, methyl ether calixarene, podand, and an octopus molecule, the agent being made in the presence of lithium.

  2. Micro network unburdens Lawrence Livermore's supercomputers

    SciTech Connect

    Cecil, A.

    1983-03-01

    Many program-development installations that rely on time-sharing systems are distributing some of the programming tasks to microcomputer networks. The Lawrence Livermore National Laboratory, for example, has installed several microcomputer local networks as front-ends to its massive Octopus network, composed of Cray-1 and Control Data Corp. 7600 mainframes. One local network, which incorporated terminals from different vendors, is used by the programming group for nuclear weapons simulation. It allows programmers to perform local text editing, which reduces the time necessary to retrieve, modify and verify code, and frees the central host for compilation and execution. It also facilitates job resubmission and user scheduling.

  3. Pygmy squids and giant brains: mapping the complex cephalopod CNS by phalloidin staining of vibratome sections and whole-mount preparations.

    PubMed

    Wollesen, T; Loesel, R; Wanninger, A

    2009-04-30

    Among bilaterian invertebrates, cephalopod molluscs (e.g., squids, cuttlefish and octopuses) have a central nervous system (CNS) that rivals in complexity that of the phylogenetically distant vertebrates (e.g., mouse and human). However, this prime example of convergent evolution has rarely been the subject of recent developmental and evolutionary studies, which may partly be due to the lack of suitable neural markers and the large size of cephalopod brains. Here, we demonstrate the usefulness of fluorescence-coupled phalloidin to characterize the CNS of cephalopods using histochemistry combined with confocal laser scanning microscopy. Whole-mount preparations of developmental stages as well as vibratome sections of embryonic and adult brains were analyzed and the benefits of this technique are illustrated. Compared to classical neuroanatomical and antibody-based studies, phalloidin labeling experiments are less time-consuming and allow a high throughput of samples. Besides other advantages summarized here, phalloidin reliably labels the entire neuropil of the CNS of all squids, cuttlefish and octopuses investigated. This facilitates high-resolution in toto reconstructions of the CNS and contributes to a better understanding of the organization of neural networks. Amenable for multi-labeling experiments employing antibodies against neurotransmitters, proteins and enzymes, phalloidin constitutes an excellent neuropil marker for the complex cephalopod CNS.

  4. A bioinspired soft manipulator for minimally invasive surgery.

    PubMed

    Ranzani, T; Gerboni, G; Cianchetti, M; Menciassi, A

    2015-05-13

    This paper introduces a novel, bioinspired manipulator for minimally invasive surgery (MIS). The manipulator is entirely composed of soft materials, and it has been designed to provide similar motion capabilities as the octopus's arm in order to reach the surgical target while exploiting its whole length to actively interact with the biological structures. The manipulator is composed of two identical modules (each of them can be controlled independently) with multi-directional bending and stiffening capabilities, like an octopus arm. In the authors' previous works, the design of the single module has been addressed. Here a two-module manipulator is presented, with the final aim of demonstrating the enhanced capabilities that such a structure can have in comparison with rigid surgical tools currently employed in MIS. The performances in terms of workspace, stiffening capabilities, and generated forces are characterized through experimental tests. The combination of stiffening capabilities and manipulation tasks is also addressed to confirm the manipulator potential employment in a real surgical scenario.

  5. Shellfish hypersensitivity: clinical and immunological characteristics.

    PubMed

    Castillo, R; Carrilo, T; Blanco, C; Quiralte, J; Cuevas, M

    1994-01-01

    Shellfish is one of the most frequent causes of food allergy. We studied 48 patients (25 male and 23 female) with a mean age of 24.2 +/- 1.8 with shellfish hypersensitivity. A clinical questionnaire was carried out and prick tests were performed using a series of aeroallergens and a battery of extracts of squid, shrimp, lobster, crab, mussel and clam. Prick tests were also performed using raw and boiled extracts from fresh squid, octopus and limpet. Total and specific IgE to these allergens were determined. The most frequent causes of symptoms were shrimp (33 cases) and squid (24 cases). The most frequently found symptoms were Urticaria/angioedema (39 patients), asthma (18 patients) and rhinitis (14 patients). Clinical association was found between Cephalopoedae and Lamelibranquiae (p < 0.05 for clam and p < 0.01 for mussel), but not among both groups and Crustaceans. Association between history and Prick was statistically significant for Crustaceae and Cephalopoedae (p < 0.01) but not for Lamalibranquiae. Association between history and CAP was not found for shellfish. Significant differences among prick-tests with raw and boiled extracts were not found. These results suggest that prick test yields better results than CAP does it, in shellfish hypersensitivity, that clinical association among shellfish hypersensitivity can occurs within the same and different Phylum reflecting common epitopes and that squid, octopus and limpet extracts contain a large amount of heat-stable allergens. PMID:8059680

  6. Comparative modeling of the latent form of a plant catechol oxidase using a molluskan hemocyanin structure.

    PubMed

    Gerdemann, Carsten; Eicken, Christoph; Galla, Hans Joachim; Krebs, Bernt

    2002-04-10

    The structure of the precursor form of catechol oxidase from sweet potatoes (Ipomoea batatas) has been modeled on the basis of the 3D structural data of mature catechol oxidase [Nat. Struct. Biol. 5 (1998) 1084] and of hemocyanin from giant octopus (Octopus dofleini) [J. Mol. Biol. 278 (1998) 855]. A C-terminal extension peptide is found in the cDNA sequence but not in the purified, mature form of catechol oxidase. Superimposition of the 3D structures of the native hemocyanin and catechol oxidase reveals a close relationship except for an additional C-terminal domain only found in the hemocyanin structure. As sequence alignment shows good homology this domain of the hemocyanin structure was used as a template to model the 3D structure of the C-terminal extension peptide of catechol oxidase. As hemocyanins show no or only weak catecholase activity due to this domain this indicates an inhibitory function of this extension peptide. Beside this possible shielding function for the precursor form, evidence for a function in copper-uptake also increases due to the location of three histidine residues in the model. PMID:11931976

  7. Systematic analysis of animals used in medieval Azerbaijan medicine.

    PubMed

    Alakbarli, Farid

    2006-06-01

    In order to study the special composition of animals used in the medieval medicine of Azerbaijan, a wide range of medieval sources on medicine and pharmacognosy from the collection of the Institute of Manuscripts of the Azerbaijan Academy of Sciences in Baku has been studied. About 40 medieval sources from the 10-18th centuries including 17 manuscripts in Turkic, Persian and Arabic have been selected as the objects of this study. As a result, 150 species of animals described in medieval Azerbaijani books on medicine and pharmacy have been identified. Many of the identified animals are mammals, (47 species or 31% of total number of identified species). The medieval authors describe 12 species of reptiles and 4 species of Amphibians (frogs, toads, salamanders and tree-frogs (Hyla arborea). 15 species of fishes described in medieval manuscripts have been identified. The identified molluscs are cuttlefish (Sepia officinalis), mussel (Mytilus edulis), octopus (Octopus vulgaris) and snail (Helix pomatia). Most crustaceans used in medieval Azerbaijan medicine belong to Decopoda. Medieval manuscripts contain numerous names of various worms and insects (ants, flies, beetles, etc.), however their exact identification is rather difficult. As usual, medieval authors unite a number of species under one name and do not give sufficient information about their morphology. Results of the research create grounds for the idea that the recommendations of the medieval authors on the medicinal application of animals can be applied to modern medicine once they have been experimentally and clinically tested.

  8. A bioinspired soft manipulator for minimally invasive surgery.

    PubMed

    Ranzani, T; Gerboni, G; Cianchetti, M; Menciassi, A

    2015-06-01

    This paper introduces a novel, bioinspired manipulator for minimally invasive surgery (MIS). The manipulator is entirely composed of soft materials, and it has been designed to provide similar motion capabilities as the octopus's arm in order to reach the surgical target while exploiting its whole length to actively interact with the biological structures. The manipulator is composed of two identical modules (each of them can be controlled independently) with multi-directional bending and stiffening capabilities, like an octopus arm. In the authors' previous works, the design of the single module has been addressed. Here a two-module manipulator is presented, with the final aim of demonstrating the enhanced capabilities that such a structure can have in comparison with rigid surgical tools currently employed in MIS. The performances in terms of workspace, stiffening capabilities, and generated forces are characterized through experimental tests. The combination of stiffening capabilities and manipulation tasks is also addressed to confirm the manipulator potential employment in a real surgical scenario. PMID:25970550

  9. An ethogram for Benthic Octopods (Cephalopoda: Octopodidae).

    PubMed

    Mather, Jennifer A; Alupay, Jean S

    2016-05-01

    The present paper constructs a general ethogram for the actions of the flexible body as well as the skin displays of octopuses in the family Octopodidae. The actions of 6 sets of structures (mantle-funnel, arms, sucker-stalk, skin-web, head, and mouth) combine to produce behavioral units that involve positioning of parts leading to postures such as the flamboyant, movements of parts of the animal with relation to itself including head bob and grooming, and movements of the whole animal by both jetting in the water and crawling along the substrate. Muscular actions result in 4 key changes in skin display: (a) chromatophore expansion, (b) chromatophore contraction resulting in appearance of reflective colors such as iridophores and leucophores, (c) erection of papillae on the skin, and (d) overall postures of arms and mantle controlled by actions of the octopus muscular hydrostat. They produce appearances, including excellent camouflage, moving passing cloud and iridescent blue rings, with only a few known species-specific male visual sexual displays. Commonalities across the family suggest that, despite having flexible muscular hydrostat movement systems producing several behavioral units, simplicity of production may underlie the complexity of movement and appearance. This systematic framework allows researchers to take the next step in modeling how such diversity can be a combination of just a few variables. (PsycINFO Database Record PMID:27078075

  10. Composition of Hydrothermal Vent Microbial Communities as Revealed by Analyses of Signature Lipids, Stable Carbon Isotopes and Aquificales Cultures

    NASA Technical Reports Server (NTRS)

    Jahnke, Linda L.; Eder, Wolfgang; Huber, Robert; Hinrichs, Kai-Uwe; Hayes, John M.; Cady, Sherry L.; DesMarais, David J.; Hope, Janet M.; Summons, Roger E.

    2001-01-01

    Extremely thermophilic microbial communities associated with the siliceous vent walls and outflow channel of Octopus Spring, Yellowstone National Park, have been examined for lipid biomarker and carbon isotopic signatures. These data were compared with that obtained from representatives of three Aquificales genera. Thermocrinis ruber, Thermocrinis sp. HI, Hydrogenobacter thermophilus, Aquifex pyrophilus and Aquifex aeolicus all contained phospholipids composed not only of the usual ester-linked fatty acids, but also ether-linked alkyl moieties. The fatty acids of all cultured organisms were dominated by very distinct pattern of n-C-20:1 and cy-C-21 compounds. The alkyl glycerol ethers were present primarily as C-18:0 monoethers with the exception of the Aquifex spp. in which dialkyl glycerol ethers with a boarder carbon-number distribution were also present. These Aquificales biomarker lipids were the major constituents in the lipid extracts of the Octopus Spring microbial samples. Two natural samples, a microbial biofilm growing in association with deposition of amorphous silica on the vent walls at 92 C, and the well-known "pink-streamer community" (PSC), siliceous filaments of a microbial consortia growing in the outflow channel at 87 C were analyzed. Both the biofilm and PSC samples contained mono- and dialkyl glycerol ethers with a prevalence of C-18 and C-20 alkyls. Phospholipid fatty acids were comprised of both the characteristic. Additional information is contained in the original extended abstract.

  11. Synaptic integration in dendrites: exceptional need for speed.

    PubMed

    Golding, Nace L; Oertel, Donata

    2012-11-15

    Some neurons in the mammalian auditory system are able to detect and report the coincident firing of inputs with remarkable temporal precision. A strong, low-voltage-activated potassium conductance (g(KL)) at the cell body and dendrites gives these neurons sensitivity to the rate of depolarization by EPSPs, allowing neurons to assess the coincidence of the rising slopes of unitary EPSPs. Two groups of neurons in the brain stem, octopus cells in the posteroventral cochlear nucleus and principal cells of the medial superior olive (MSO), extract acoustic information by assessing coincident firing of their inputs over a submillisecond timescale and convey that information at rates of up to 1000 spikes s(-1). Octopus cells detect the coincident activation of groups of auditory nerve fibres by broadband transient sounds, compensating for the travelling wave delay by dendritic filtering, while MSO neurons detect coincident activation of similarly tuned neurons from each of the two ears through separate dendritic tufts. Each makes use of filtering that is introduced by the spatial distribution of inputs on dendrites. PMID:22930273

  12. The effect of prosody on conceptual combination.

    PubMed

    Lynott, Dermot; Connell, Louise

    2010-08-01

    Research into people's comprehension of novel noun-noun phrases has long neglected the possible influences of prosody during meaning construction. At the same time, work in conceptual combination has disagreed about whether different classes of interpretation emerge from single or multiple processes; for example, whether people use distinct mechanisms when they interpret octopus apartment as property-based (e.g., an apartment with eight rooms) or relation-based (e.g., an apartment where an octopus lives). In two studies, we manipulate the prosodic emphasis patterns of novel noun-noun combinations (placing stress on the modifier noun, the head noun, or dual stress on both nouns) and ask participants to generate an interpretation for the novel phrase. Results show that people are faster to generate property-based interpretations when dual emphasis stresses both nouns equally, with prosody having little effect on the speed of relation-based interpretations. These findings highlight a role for prosody during meaning construction and underline important differences between relation- and property-based interpretations that are difficult to reconcile with unitary process views of conceptual combination. PMID:21564245

  13. Polarized light scattering as a probe for changes in chromosome structure

    SciTech Connect

    Shapiro, D.B.

    1993-10-01

    Measurements and calculations of polarized light scattering are applied to chromosomes. Calculations of the Mueller matrix, which completely describes how the polarization state of light is altered upon scattering, are developed for helical structures related to that of chromosomes. Measurements of the Mueller matrix are presented for octopus sperm heads, and dinoflagellates. Comparisons of theory and experiment are made. A working theory of polarized light scattering from helices is developed. The use of the first Born approximation vs the coupled dipole approximation are investigated. A comparison of continuous, calculated in this work, and discrete models is also discussed. By comparing light scattering measurements with theoretical predictions the average orientation of DNA in an octopus sperm head is determined. Calculations are made for the Mueller matrix of DNA plectonemic helices at UV, visible and X-ray wavelengths. Finally evidence is presented that the chromosomes of dinoflagellates are responsible for observed differential scattering of circularly-polarized light. This differential scattering is found to vary in a manner that is possibly correlated to the cell cycle of the dinoflagellates. It is concluded that by properly choosing the wavelength probe polarized light scattering can provide a useful tool to study chromosome structure.

  14. IRBP-like proteins in the eyes of six cephalopod species--immunochemical relationship to vertebrate interstitial retinol-binding protein (IRBP) and cephalopod retinal-binding protein.

    PubMed

    Fong, S L; Lee, P G; Ozaki, K; Hara, R; Hara, T; Bridges, C D

    1988-01-01

    SDS polyacrylamide gel electrophoresis and immunoblotting were used to examine soluble proteins from the eyes of six species of cephalopods i.e. Lolliguncula brevis, Sepia officinalis, Octopus maya, Octopus bimaculoides, Rossia pacifica and Loligo opalescens. All species had a protein ("IRBP") with molecular weight virtually identical with vertebrate interstitial retinol-binding protein (IRBP) averaging 132,400 +/- 700 (n = 6). "IRBP" reacted on nitrocellulose blot transfers with rabbit antibovine IRBP and rabbit antifrog IRBP antibodies. Unlike vertebrate IRBP, cephalopod "IRBP" (from L. brevis) did not bind exogenous retinol or concanavalin A. The N-terminal amino acid appeared to be blocked in samples electroeluted from SDS gels. The antifrog IRBP antibodies also reacted with a series of proteins with molecular weights between 46,000 and 47,000, identified as retinal-binding protein (RALBP) with anti-RALBP antibodies. Anti-IRBP also reacted with pure RALBP prepared from Todarodes pacificus. Occasionally, anti-RALBP antibodies were seen to react weakly with "IRBP" in some cephalopods. We conclude that RALBP, cephalopod "IRBP" and vertebrate IRBP share a common but distant ancestry, and that a protein resembling IRBP appeared before the vertebrates diverged from the invertebrates. Both RALBP and IRBP appear to have analogous functions in shuttling retinoids between rhodopsin and the corresponding isomerizing system, retinochrome in the cephalopods and retinol isomerase in the vertebrates. The function of cephalopod "IRBP" is unknown. PMID:3195063

  15. Genetic identification of squids (families Ommastrephidae and Loliginidae) by PCR-RFLP and FINS methodologies.

    PubMed

    Santaclara, Francisco J; Espiñeira, Montserrat; Vieites, Juan M

    2007-11-28

    Cephalopods are a taxonomic group that contains a great number of families, genera and species, with many of them very important at the commercial level. The existence of very similar species in this class added up to the transformation process applied to them makes it difficult or even impossible for species identification based on morphological characterization. Moreover, the global commerce makes it possible that one determined species can be marketed in its antipodes. These questions suggest the necessity of molecular techniques to solve this situation. In the present work, a genetic method was developed on the basis of the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and forensically informative nucleotide sequencing (FINS) technique and makes possible the identification of more than 20 species belonging to the families Ommastrephidae and Loliginidae, as well as some octopus and sepia species. The PCR was employed to amplify 651 and 208 bp fragments of the mitochondrial cytochrome b gene. These molecular systems were applied to fresh, frozen, precooked, even canned cephalopods, allowing for the identification of the species included in these products. Therefore, these molecular tools could be applied in questions related to correct labeling, traceability, and importation controls of squids, sepias, and octopuses.

  16. Uncultivated cyanobacteria, Chloroflexus-like inhabitants, and spirochete-like inhabitants of a hot spring microbial mat.

    PubMed Central

    Weller, R; Bateson, M M; Heimbuch, B K; Kopczynski, E D; Ward, D M

    1992-01-01

    Analysis of 16S rRNA sequences retrieved as cDNA (16S rcDNA) from the Octopus Spring cyanobacterial mat has permitted phylogenetic characterization of some uncultivated community members, expanding our knowledge or diversity within this microbial community. Two new cyanobacterial 16S rRNA sequences were discovered, raising to four the number of cyanobacterial sequence types known to occur in the mat. None of the sequences found is that of the cultivated thermophilic cyanobacterium Synechococcus lividus. A new 16S rRNA sequence characteristic of green nonsulfur bacteria and their relatives was discovered, raising to two the number of such sequences known to exist in the mat. Both are unique among the 16S rRNA sequences of cultivated members of this group, including an Octopus Spring isolate of Chloroflexus aurantiacus and Heliothrix oregonensis, whose sequences we report herein. Two spirochete-like 16S rRNA sequences were discovered. One can be placed in the leptospira subdivision of the spirochete group, but the other has such a loose affiliation with the spirochete group that it might actually belong to an as yet unrecognized subdivision or even to a new eubacterial line of descent. PMID:1282313

  17. Hunt for Palytoxins in a Wide Variety of Marine Organisms Harvested in 2010 on the French Mediterranean Coast.

    PubMed

    Biré, Ronel; Trotereau, Sophie; Lemée, Rodolphe; Oregioni, Davide; Delpont, Christine; Krys, Sophie; Guérin, Thierry

    2015-08-01

    During the summer of 2010, 31 species including fish, echinoderms, gastropods, crustaceans, cephalopods and sponges were sampled in the Bay of Villefranche on the French Mediterranean coast and screened for the presence of PLTX-group toxins using the haemolytic assay. Liquid chromatography tandem mass spectrometry (LC-MS/MS) was used for confirmatory purposes and to determine the toxin profile. The mean toxin concentration in the whole flesh of all sampled marine organisms, determined using the lower- (LB) and upper-bound (UB) approach was 4.3 and 5.1 µg·kg(-1), respectively, with less than 1% of the results exceeding the European Food Safety Authority (EFSA) threshold of 30 µg·kg(-1)and the highest values being reported for sea urchins (107.6 and 108.0 µg·kg(-1)). Toxins accumulated almost exclusively in the digestive tube of the tested species, with the exception of octopus, in which there were detectable toxin amounts in the remaining tissues (RT). The mean toxin concentration in the RT of the sampled organisms (fishes, echinoderms and cephalopods) was 0.7 and 1.7 µg·kg(-1) (LB and UB, respectively), with a maximum value of 19.9 µg·kg(-1) for octopus RT. The herbivorous and omnivorous organisms were the most contaminated species, indicating that diet influences the contamination process, and the LC-MS/MS revealed that ovatoxin-a was the only toxin detected. PMID:26308009

  18. A two-step method for developing a control rod program for boiling water reactors

    SciTech Connect

    Taner, M.S.; Levine, S.H. ); Hsiao, M.Y. )

    1992-01-01

    This paper reports on a two-step method that is established for the generation of a long-term control rod program for boiling water reactors (BWRs). The new method assumes a time-variant target power distribution in core depletion. In the new method, the BWR control rod programming is divided into two steps. In step 1, a sequence of optimal, exposure-dependent Haling power distribution profiles is generated, utilizing the spectral shift concept. In step 2, a set of exposure-dependent control rod patterns is developed by using the Haling profiles generated at step 1 as a target. The new method is implemented in a computer program named OCTOPUS. The optimization procedure of OCTOPUS is based on the method of approximation programming, in which the SIMULATE-E code is used to determine the nucleonics characteristics of the reactor core state. In a test in cycle length over a time-invariant, target Haling power distribution case because of a moderate application of spectral shift. No thermal limits of the core were violated. The gain in cycle length could be increased further by broadening the extent of the spetral shift.

  19. Oxytocin/vasopressin and gonadotropin-releasing hormone from cephalopods to vertebrates.

    PubMed

    Minakata, Hiroyuki

    2010-07-01

    Recent advances in peptide search methods have revealed two peptide systems that have been conserved through metazoan evolution. Members of the oxytocin/vasopressin-superfamily have been identified from protostomian and deuterostomian animals, indicating that the oxytocin/vasopressin hormonal system represents one of the most ancient systems. In most protostomian animals, a single member of the superfamily shares oxytocin-like and vasopressin-like actions. Co-occurrence of two members has been discovered in modern cephalopods, octopus, and cuttlefish. We propose that cephalopods have developed two peptides in the molluscan evolutionary lineage like vertebrates have established two lineages in the oxytocin/vasopressin superfamily. The existence of gonadotropin-releasing hormone (GnRH) in protostomian animals was initially suggested by immunohistochemical analysis using chordate GnRH antibodies. A peptide with structural features similar to those of chordate GnRHs was originally isolated from octopus, and an identical peptide has been characterized from squid and cuttlefish. Novel forms of GnRH-like molecules from other molluscs, an annelid, arthropods, and nematodes demonstrate somewhat conserved structures at the N-terminal regions; but structures of the C-terminal regions critical to gonadotropin-releasing activity are diverse. These findings may be important for the study of the molecular evolution of GnRH in protostomian animals.

  20. Hunt for Palytoxins in a Wide Variety of Marine Organisms Harvested in 2010 on the French Mediterranean Coast

    PubMed Central

    Biré, Ronel; Trotereau, Sophie; Lemée, Rodolphe; Oregioni, Davide; Delpont, Christine; Krys, Sophie; Guérin, Thierry

    2015-01-01

    During the summer of 2010, 31 species including fish, echinoderms, gastropods, crustaceans, cephalopods and sponges were sampled in the Bay of Villefranche on the French Mediterranean coast and screened for the presence of PLTX-group toxins using the haemolytic assay. Liquid chromatography tandem mass spectrometry (LC-MS/MS) was used for confirmatory purposes and to determine the toxin profile. The mean toxin concentration in the whole flesh of all sampled marine organisms, determined using the lower- (LB) and upper-bound (UB) approach was 4.3 and 5.1 µg·kg−1, respectively, with less than 1% of the results exceeding the European Food Safety Authority (EFSA) threshold of 30 µg·kg−1 and the highest values being reported for sea urchins (107.6 and 108.0 µg·kg−1). Toxins accumulated almost exclusively in the digestive tube of the tested species, with the exception of octopus, in which there were detectable toxin amounts in the remaining tissues (RT). The mean toxin concentration in the RT of the sampled organisms (fishes, echinoderms and cephalopods) was 0.7 and 1.7 µg·kg−1 (LB and UB, respectively), with a maximum value of 19.9 µg·kg−1 for octopus RT. The herbivorous and omnivorous organisms were the most contaminated species, indicating that diet influences the contamination process, and the LC-MS/MS revealed that ovatoxin-a was the only toxin detected. PMID:26308009