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Sample records for adult sea scallops

  1. 50 CFR 648.59 - Sea Scallop Access Areas.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Sea Scallop Access Areas. 648.59 Section... Atlantic Sea Scallop Fishery § 648.59 Sea Scallop Access Areas. (a) Delmarva Sea Scallop Access Area. (1... in or from the area known as the Delmarva Sea Scallop Access Area, described in paragraph (a)(2)...

  2. 50 CFR 648.57 - Sea scallop area rotation program.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Sea scallop area rotation program. 648.57... Measures for the Atlantic Sea Scallop Fishery § 648.57 Sea scallop area rotation program. An area rotation... in § 648.58, and/or Sea Scallop Access Areas defined in § 648.59, subject to the Sea Scallop...

  3. 50 CFR 648.59 - Sea Scallop Access Areas.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Scallop Access Area is open to scallop vessels, unless transiting pursuant to paragraph (f) of this... Access Area is open to scallop vessels, unless transiting pursuant to paragraph (f) of this section. (5... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Sea Scallop Access Areas. 648.59...

  4. 78 FR 73499 - Proposed Information Collection; Comment Request; Atlantic Sea Scallops Amendment 10 Data Collection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-06

    ... Sea Scallops Amendment 10 Data Collection AGENCY: National Oceanic and Atmospheric Administration... (NMFS) Northeast Region manages the Atlantic sea scallop (scallop) fishery of the Exclusive Economic Zone (EEZ) off the East Coast under the Atlantic Sea Scallop Fishery Management Plan (FMP)....

  5. 77 FR 73957 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Closure of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-12

    ... Adjustment 22 to the Scallop FMP (Framework 22) (76 FR 43774; July 21, 2011), which used 2010 scallop... policy guidelines for the use of emergency rules (62 FR 44421; August 21, 1997) specify the following... United States; Atlantic Sea Scallop Fishery; Closure of the Elephant Trunk Area AGENCY: National...

  6. 50 CFR 648.59 - Sea Scallop Access Areas.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...°01.27′ W. (1) CAIA1 41°26′ N. 68°30′ W. 1 From Point CAIA3 to Point CAIA4 along the western boundary... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Sea Scallop Access Areas. 648.59 Section... March 1, 2014, through February 29, 2016 (i.e., fishing year 2014 and 2015), vessels issued...

  7. 75 FR 22073 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Framework Adjustment 21

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-27

    ... scallop fishery: Total allowable catch (TAC); open area days-at-sea (DAS) and Sea Scallop Access Area... components: Open area DAS; individual access area trips for limited access vessels; IFQ allocations.... Open Area DAS Allocations This action would implement the following vessel-specific DAS allocations...

  8. 50 CFR 648.59 - Sea Scallop Access Areas.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Delmarva Scallop Access Area schedule and TACs specified in paragraph (a)(3) of this section for fishing... vessels in the Delmarva Access Area shall be based on the TAC for the access area, which shall be... Delmarva Access Area scallop TACs for limited access scallop vessels are 5,886,000 lb (2,670 mt) in...

  9. 75 FR 55304 - Proposed Information Collection; Comment Request; Atlantic Sea Scallops Amendment 10 Data Collection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-10

    ... National Oceanic and Atmospheric Administration Proposed Information Collection; Comment Request; Atlantic Sea Scallops Amendment 10 Data Collection AGENCY: National Oceanic and Atmospheric Administration... copies of the information collection instrument and instructions should be directed to Peter...

  10. Paralytic shellfish toxins in the sea scallop Placopecten magellanicus on Georges Bank: Implications for an offshore roe-on and whole scallop fishery

    NASA Astrophysics Data System (ADS)

    DeGrasse, Stacey; Vanegas, Camilo; Conrad, Stephen

    2014-05-01

    To protect public health from the potential risk of paralytic shellfish poisoning (PSP) in sea scallops, Placopecten magellanicus, from the Atlantic offshore U.S. waters of Georges Bank, harvesting of roe-on or whole scallops is banned. Only adductor muscles may be sold if harvested from Georges Bank, Gulf of Maine, or the PSP closure areas as far west as 71° West Longitude. Given the limited toxicity data available for sea scallops from this region both prior to and subsequent to implementation of this management strategy, this study sought a more extensive spatial and temporal evaluation of sea scallop gonad and viscera toxicities that would inform management decisions related to the roe-on and whole scallop fishery. Both overall toxicity and toxin composition were measured for sea scallop gonads and viscera collected from 232 stations in 2007 and 23 in 2010. Overall toxicity was assessed using two screening methods: field-deployable Jellett Rapid Tests (JRT) and quantitative, laboratory-based receptor binding assays (in 2007). Additionally, a quantitative liquid chromatography with fluorescence detection (LC-FD) method was used to determine toxin composition and overall toxicity (in 2010). The at-sea qualitative JRT screening tool results, whereby a positive indicated the sample contained at least 40 μg saxitoxin (STX) equivalents 100 g-1, were often inconsistent with results obtained using the quantitative methods. Sea scallop viscera toxicity represented the majority of toxin load in the organism and was often in excess of the regulatory guidance level. Sea scallop gonads accounted for a small percentage of total toxicity, but at times reached unsafe levels. Toxin composition in both the gonads and viscera was dominated by STX and gonyautoxin 2/3, as has been reported in previous studies. No predictive indices of gonad toxicity were found. Results at this time do not support a roe-on or whole scallop fishery on Georges Bank. While access restrictions to

  11. 50 CFR 648.59 - Sea Scallop Access Areas.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Closed Area I Access Area shall be based on the TAC for the access area, which will be determined through... allocated to limited access vessels in the Closed Area I Access Area shall be based on the TAC for the... paragraph (b)(5)(i). The Closed Area I Access Area scallop TAC for limited access scallop vessels is...

  12. 76 FR 23940 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Framework Adjustment 22

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-29

    ... measures implemented through Framework 21 (75 FR 36559; June 28, 2010), the Council proposed this trip... schedule that was implemented through Framework 16 to the FMP (69 FR 63460; November 2, 2004). The Council... (LAGC) fleets; open area days-at-sea (DAS) and Sea Scallop Access Area (access area) trip...

  13. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (North Atlantic): Sea scallop. [Plactopecten magellanicus

    SciTech Connect

    Mullen, D.M.; Moring, J.R.

    1986-08-01

    The sea scallop, Placopecten magellanicus, is a commercially important shellfish found from North Carolina to the Gulf of St. Lawrence in intertidal to deep waters. Scallops spawn at age 1 from July to October, releasing up to one million eggs each year. Up to 8 cm in size, scallops are active in response to disturbances, but those over 9 cm in size do not move. The US commercial fishery has been active for over 100 years, and landings in 1982 were 9700 t, valued at $78 million. Over 75% of the commercial landings of all scallops occur in New England, principally in Massachusetts. Scallops are collected by commercial dredges and scuba divers. A wide variety of animals prey on scallops, and predation by several species of fishes may increase following injuries caused by commercial dredges.

  14. Repaired shell damage in the commercial scallop Zygochlamys patagonica (King & Broderip, 1832), Argentine Sea

    NASA Astrophysics Data System (ADS)

    Schejter, Laura; Bremec, Claudia

    2007-08-01

    We present an overview of repaired shell damage in the scallop Zygochlamys patagonica in the commercial beds of the Argentine Sea. Presence of scars was registered in 11 962 scallops, ranging from 20 to 90 mm total height, from the fishing grounds in 2003 and also in 1995 (pre-fishery condition). Values of percentage of scarring (presence) were variable in all areas. Samples collected in 1995 showed the highest percentage of scars. As the highest records of scarring were registered in pre-fishery conditions, it is not possible to regard these marks as absolute indicators of anthropogenic disturbance caused by trawling activities. Moderate and severe damage was mostly recorded in individuals of commercial size (≥ 55 mm). This indicates not only the fragility of smaller scallops, but also the accumulation of damage in older specimens, probably more resistant to damage because of their thicker shells. The selective removal of commercial individuals could explain in part our results that indicate a higher percentage of repaired shell damage in 1995, when the average size of the population was also higher. Future investigations are needed to assess effects of scarring at different shell sizes (ages) and relate these to levels of survival in Patagonian scallops thrown back into the sea during processing on board.

  15. Ecological effects of co-culturing sea cucumber Apostichopus japonicus (Selenka) with scallop Chlamys farreri in earthen ponds

    NASA Astrophysics Data System (ADS)

    Ren, Yichao; Dong, Shuanglin; Qin, Chuanxin; Wang, Fang; Tian, Xiangli; Gao, Qinfeng

    2012-01-01

    Monthly changes in sedimentation and sediment properties were studied for three different culture treatments: sea cucumber monoculture (Mc), sea cucumber and scallop polyculture (Ps-c) and scallop monoculture (Ms). Results indicated that the survival rate of sea cucumber was significantly higher in Ps-c cultures than in Mc cultures. Sea cucumber yield was 69.6% higher in Ps-c culture than in Mc culture. No significant differences in body weight and scallop shell length were found between Ps-c and Ms cultures. The mean sedimentation rate of total particulate matter (TPM) was 72.2 g/(m2·d) in Ps-c cultures, with a maximum of 119.7 g/(m2·d), which was markedly higher than that of Mc (mean value). Sedimentation rates of organic matter (OM), total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) in Ps-c cultures were also significantly higher than those in Mc cultures. TOC and TN contents of sediment increased rapidly in the first 5 months in Ms cultures and remained at a high level. TOC and TN contents in Mc and Ps-c cultures decreased during sea cucumber feeding seasons and increased during sea cucumber dormancy periods (summer and winter). The study demonstrates that co-culture of sea cucumber and scallop in earthen ponds is an alternative way to alleviate nutrient loads and improve water quality in coastal aquaculture systems. Moreover, it provides the additional benefit of an increased sea cucumber yield.

  16. An Integrated Assessment Model for Helping the United States Sea Scallop (Placopecten magellanicus) Fishery Plan Ahead for Ocean Acidification and Warming.

    PubMed

    Cooley, Sarah R; Rheuban, Jennie E; Hart, Deborah R; Luu, Victoria; Glover, David M; Hare, Jonathan A; Doney, Scott C

    2015-01-01

    Ocean acidification, the progressive change in ocean chemistry caused by uptake of atmospheric CO2, is likely to affect some marine resources negatively, including shellfish. The Atlantic sea scallop (Placopecten magellanicus) supports one of the most economically important single-species commercial fisheries in the United States. Careful management appears to be the most powerful short-term factor affecting scallop populations, but in the coming decades scallops will be increasingly influenced by global environmental changes such as ocean warming and ocean acidification. In this paper, we describe an integrated assessment model (IAM) that numerically simulates oceanographic, population dynamic, and socioeconomic relationships for the U.S. commercial sea scallop fishery. Our primary goal is to enrich resource management deliberations by offering both short- and long-term insight into the system and generating detailed policy-relevant information about the relative effects of ocean acidification, temperature rise, fishing pressure, and socioeconomic factors on the fishery using a simplified model system. Starting with relationships and data used now for sea scallop fishery management, the model adds socioeconomic decision making based on static economic theory and includes ocean biogeochemical change resulting from CO2 emissions. The model skillfully reproduces scallop population dynamics, market dynamics, and seawater carbonate chemistry since 2000. It indicates sea scallop harvests could decline substantially by 2050 under RCP 8.5 CO2 emissions and current harvest rules, assuming that ocean acidification affects P. magellanicus by decreasing recruitment and slowing growth, and that ocean warming increases growth. Future work will explore different economic and management scenarios and test how potential impacts of ocean acidification on other scallop biological parameters may influence the social-ecological system. Future empirical work on the effect of ocean

  17. An Integrated Assessment Model for Helping the United States Sea Scallop (Placopecten magellanicus) Fishery Plan Ahead for Ocean Acidification and Warming

    PubMed Central

    2015-01-01

    Ocean acidification, the progressive change in ocean chemistry caused by uptake of atmospheric CO2, is likely to affect some marine resources negatively, including shellfish. The Atlantic sea scallop (Placopecten magellanicus) supports one of the most economically important single-species commercial fisheries in the United States. Careful management appears to be the most powerful short-term factor affecting scallop populations, but in the coming decades scallops will be increasingly influenced by global environmental changes such as ocean warming and ocean acidification. In this paper, we describe an integrated assessment model (IAM) that numerically simulates oceanographic, population dynamic, and socioeconomic relationships for the U.S. commercial sea scallop fishery. Our primary goal is to enrich resource management deliberations by offering both short- and long-term insight into the system and generating detailed policy-relevant information about the relative effects of ocean acidification, temperature rise, fishing pressure, and socioeconomic factors on the fishery using a simplified model system. Starting with relationships and data used now for sea scallop fishery management, the model adds socioeconomic decision making based on static economic theory and includes ocean biogeochemical change resulting from CO2 emissions. The model skillfully reproduces scallop population dynamics, market dynamics, and seawater carbonate chemistry since 2000. It indicates sea scallop harvests could decline substantially by 2050 under RCP 8.5 CO2 emissions and current harvest rules, assuming that ocean acidification affects P. magellanicus by decreasing recruitment and slowing growth, and that ocean warming increases growth. Future work will explore different economic and management scenarios and test how potential impacts of ocean acidification on other scallop biological parameters may influence the social-ecological system. Future empirical work on the effect of ocean

  18. 50 CFR 648.60 - Sea scallop area access program requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... scallop vessels. A full-time scallop vessel may take two trips in the Elephant Trunk Access Area, one trip... Delmarva and Elephant Trunk Access Areas specified in § 648.59(a) and (e). For example, a full-time vessel may declare up to two trips in the Elephant Trunk Access Area or up to one trip in the Elephant...

  19. 78 FR 42890 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery and Northeast...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-18

    ..., 2013, the final rule for Joint Framework 24/49 published in the Federal Register (78 FR 27088). The... NGOM as a distinct management area through Amendment 11 to the Scallop FMP (73 FR 20090; April 14, 2008... scallop trips on which an observer is carried onboard the vessel, regardless of whether the vessel...

  20. 75 FR 63721 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Framework Adjustment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-18

    ..., the final rule for Framework 21 published in the Federal Register (75 FR 36559). The purpose of... through the final rule to Amendment 11 to the Scallop FMP (April 14, 2008; 73 FR 20090). These... (April 27, 2010; 75 FR 22073) and final rules to implement Framework 21. Classification Pursuant to 5...

  1. 50 CFR 648.60 - Sea scallop area access program requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Reallocation of trips into open areas. If the yellowtail flounder TAC allocated for a Scallop Access Area... conducted during the last 60 days of the open period or season for the Access Area is terminated before... is open (March 1, 2012, through April 29, 2012). If an Access Area is not open in the...

  2. 78 FR 16573 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery and Northeast...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-15

    ... according to Amendment 11 to the Scallop FMP (Amendment 11; 72 FR 20090; April 14, 2008) fleet allocations... as sub-ACLs and sub-ACTs, respectively, throughout this action. Amendment 15 (76 FR 43746; July 21... closures of these areas implemented through MSA emergency actions (77 FR 64915 (October 24, 2012) and 77...

  3. 78 FR 27088 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery and Northeast...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-09

    ... (78 FR 16574), with a 15-day public comment period that ended April 1, 2013. NMFS received eight... the Scallop FMP (Amendment 11; 72 FR 20090; April 14, 2008) fleet allocations, with 94.5 percent...-ACTs, respectively, throughout this action. Amendment 15 (76 FR 43746; July 21, 2011) specified that...

  4. 50 CFR 648.60 - Sea scallop access area program requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... yellowtail flounder TACs. A limited access scallop vessel that is declared into a trip and fishing within the..../Canada Area TAC availability. After declaring a trip into and fishing in the Closed Area I or Closed Area... Regional Administrator has not issued a notice that the U.S./Canada yellowtail flounder TAC specified...

  5. 50 CFR 648.60 - Sea scallop access area program requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) Reallocation of trips into open areas. If the yellowtail flounder TAC allocated for a Scallop Access Area... kg) 6,000 lb (2,722 kg) (ii) NE multispecies possession limits and yellowtail flounder TACs. A... size restrictions specified under § 648.83(a)(1). (1) (2) U.S./Canada Area TAC availability....

  6. 77 FR 28311 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Closure of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-14

    ... Word or Excel, WordPerfect, or Adobe PDF file formats only FOR FURTHER INFORMATION CONTACT: Emily... Framework Adjustment 22 to the Scallop FMP (Framework 22) (76 FR 43774, July 21, 2011). Framework 22 set the... guidelines for the use of emergency rules (62 FR 44421; August 21, 1997) specify the following three...

  7. Survival, growth and immune activity of scallop Chlamys farreri cultured at different depths in Haizhou Bay (Yellow Sea, China) during hot season

    NASA Astrophysics Data System (ADS)

    Yu, Zonghe; Yang, Hongsheng; Liu, Baozhong; Xing, Kun; Zhang, Libin; Xu, Qiang

    2010-05-01

    Survival, growth and immune response of the scallop, Chlamys farreri, cultured in lantern nets at five different depths (2, 5, 10, 15, and 20 m below the sea surface) were studied in Haizhou Bay during the hot season (summer and autumn) of 2007. Survival and growth rates were quantified bimonthly. Immune activities in hemolymph (superoxide dismutase (SOD) and acid phosphatase (ACP)) were measured to evaluate the health of scallops at the end of the study. Environmental parameters at the five depths were also monitored during the experiment. Mortalities mainly occurred during summer. Survival of scallops suspended at 15 m (78.0%) and 20 m (86.7%) was significantly higher than at 2 m (62.9%), 5 m (60.8%) or 10 m (66.8%) at the end of the study. Mean shell height grew significantly faster at 10 m (205.0 μm/d) and 20 m (236.9 μm/d) than at 2, 5 or 15 m in summer (July 9 to September 1); however, shell growth rate at 20 m was significantly lower than at the other four depths in autumn (September 2 to November 6). In contrast to summer, scallops at 5 m grew faster (262.9 μm/d) during autumn. The growth of soft tissue at different depths showed a similar trend to the shell. Growth rates of shell height and soft tissue were faster in autumn than in summer, with the exception of shell height at 20 m. SOD activity of scallops increased with depth, and ACP activity was significantly higher at 15 and 20 m than at other depths, which suggests that scallops were healthier near the bottom. Factors explaining the depth-related mortality and growth of scallops are also discussed. We conclude that the mass mortality of scallop, C. farreri, during summer can be prevented by moving the culture area to deeper water and yield can be maximized by suspending the scallops in deep water during summer and then transferring them to shallow water in autumn.

  8. Identification of a Mycobacterium sp. as the causative agent of orange nodular lesions in the Atlantic sea scallop Placopecten magellanicus.

    PubMed

    Grimm, Catherine; Huntsberger, Carl; Markey, Kathryn; Inglis, Susan; Smolowitz, Roxanna

    2016-03-30

    The Atlantic sea scallop Placopecten magellanicus is an economically important species in the offshore fisheries on the east coast of the USA. Recently, animals collected from waters ranging from Massachusetts to Maryland have shown variably sized (up to 1 cm in diameter) orange nodular foci, predominantly in the adductor muscle tissue, but also in other organs. Histological evaluation of the nodular lesions showed rod-shaped bacteria that stain acid-fast positive and Gram-positive. PCR methodology was employed to identify the causative organism of the nodules as a Mycobacterium sp. using analysis of the partial 16S gene and the 16S-23S internal transcribed spacer region. Based upon genotypic findings, the causative bacterium fits well into the genus Mycobacterium. PMID:27025312

  9. 77 FR 52 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Framework Adjustment 23

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-03

    ... measures to: Minimize impacts on sea turtles through the requirement of a turtle deflector dredge; improve.... According to recent research indicating where sea turtle interactions most often occur, the proposed area... loggerheads, but Kemps ridley turtles and one green sea turtle have also been observed to interact...

  10. Seasonal variation in biomarkers in blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua): implications for environmental monitoring in the Barents Sea.

    PubMed

    Nahrgang, J; Brooks, S J; Evenset, A; Camus, L; Jonsson, M; Smith, T J; Lukina, J; Frantzen, M; Giarratano, E; Renaud, P E

    2013-02-01

    In the Barents Sea, the limited data on biological relevant indicators and their responses to various anthropogenic stressors have hindered the development of a consistent scientific basis for selecting indicator species and developing practical procedures for environmental monitoring. Accordingly, the main aim of the present study was to develop a common set of baseline values for contaminants and biomarkers in three species, and to identify their strengths and limitations in monitoring of the Barents Sea. Blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua) were sampled from a north Norwegian fjord in March, June, September and December 2010. Digestive glands from the bivalve species and liver from Atlantic cod were analysed for biomarkers of oxidative stress (catalase [CAT], glutathione peroxidase [GPX], glutathione-S-transferase activities [GST], lipid peroxidation as thiobarbituric reactive substances [TBARS] and total oxyradical scavenging capacity [TOSC]), biotransformation (ethoxyresorufine-O-deethylase activity [EROD]) and general stress (lysosomal membrane stability [LMS]). Concentrations of polycyclic aromatic hydrocarbons (PAHs) and metals in the bivalves and PAH metabolites in fish bile were quantified. Finally, energy reserves (total lipids, proteins and carbohydrates) and electron transport system (ETS) activity in the digestive gland of the bivalves and liver of Atlantic cod provided background information for reproductive cycle and general physiological status of the organisms. Blue mussel and Icelandic scallop showed very similar trends in biological cycle, biomarker expression and seasonality. Biomarker baselines in Atlantic cod showed weaker seasonal variability. However, important biological events may have been undetected due to the large time intervals between sampling occasions. Physiological biomarkers such as energy reserves and ETS activity were recommended as complementary parameters to the

  11. Mixed Effects of Elevated pCO2 on Fertilisation, Larval and Juvenile Development and Adult Responses in the Mobile Subtidal Scallop Mimachlamys asperrima (Lamarck, 1819)

    PubMed Central

    Scanes, Elliot; Parker, Laura M.; O’Connor, Wayne A.; Ross, Pauline M.

    2014-01-01

    Ocean acidification is predicted to have severe consequences for calcifying marine organisms especially molluscs. Recent studies, however, have found that molluscs in marine environments with naturally elevated or fluctuating CO2 or with an active, high metabolic rate lifestyle may have a capacity to acclimate and be resilient to exposures of elevated environmental pCO2. The aim of this study was to determine the effects of near future concentrations of elevated pCO2 on the larval and adult stages of the mobile doughboy scallop, Mimachlamys asperrima from a subtidal and stable physio-chemical environment. It was found that fertilisation and the shell length of early larval stages of M. asperrima decreased as pCO2 increased, however, there were less pronounced effects of elevated pCO2 on the shell length of later larval stages, with high pCO2 enhancing growth in some instances. Byssal attachment and condition index of adult M. asperrima decreased with elevated pCO2, while in contrast there was no effect on standard metabolic rate or pHe. The responses of larval and adult M. asperrima to elevated pCO2 measured in this study were more moderate than responses previously reported for intertidal oysters and mussels. Even this more moderate set of responses are still likely to reduce the abundance of M. asperrima and potentially other scallop species in the world’s oceans at predicted future pCO2 levels. PMID:24733125

  12. Fisheries Closed Areas Strengthen Scallop Larval Settlement and Connectivity Among Closed Areas and Across International Open Fishing Grounds: A Model Study

    NASA Astrophysics Data System (ADS)

    Davies, Kimberley T. A.; Gentleman, W. C.; DiBacco, C.; Johnson, C. L.

    2015-09-01

    This study examined whether a measured increase in average body size of adult sea scallops inside three fishery closed areas on Georges Bank (GB), United States (US), was sufficient to increase larval supply to closed areas and open fishing areas in both US and Canadian areas of the Bank. The effects of adult scallop density-at-size and fecundity-at-size on egg production were compared among open and closed fishery areas, countries, and time periods before and after the closed areas were established. Estimated egg production was then used to define spawning conditions in a coupled biological-physical larval tracking model that simulated larval development, mortality, and dispersal. Results showed that order of magnitude increases in larval settlement after closure were facilitated by increases in size-dependant egg production inside and dispersal from Closed Areas I and II, but not Nantucket Lightship Closed Area. The distributions of both egg production and larval settlement became more uniform across the Bank, causing the relative contribution of Canadian larvae to US scallop aggregations to decrease after establishment of Closed Areas I and II. Decreases in small and medium-sized scallop density in Canada and decreases in large scallops over the US-Southern Flank after closure caused local declines in egg production but were not sufficient to negatively affect larval settlement at the regional scale. Our model suggests that the establishment of fishery closed areas on GB considerably strengthened larval supply and settlement within and among several adult scallop aggregations.

  13. Stock enhancement or sea ranching? Insights from monitoring the genetic diversity, relatedness and effective population size in a seeded great scallop population (Pecten maximus).

    PubMed

    Morvezen, R; Boudry, P; Laroche, J; Charrier, G

    2016-09-01

    The mass release of hatchery-propagated stocks raises numerous questions concerning its efficiency in terms of local recruitment and effect on the genetic diversity of wild populations. A seeding program, consisting of mass release of hatchery-produced juveniles in the local naturally occurring population of great scallops (Pecten maximus L.), was initiated in the early 1980s in the Bay of Brest (France). The present study aims at evaluating whether this seeding program leads to actual population enhancement, with detectable effects on genetic diversity and effective population size, or consists of sea ranching with limited genetic consequences on the wild stock. To address this question, microsatellite-based genetic monitoring of three hatchery-born and naturally recruited populations was conducted over a 5-year period. Results showed a limited reduction in allelic richness but a strong alteration of allelic frequencies in hatchery populations, while genetic diversity appeared very stable over time in the wild populations. A temporal increase in relatedness was observed in both cultured stock and wild populations. Effective population size (Ne) estimates were low and variable in the wild population. Moreover, the application of the Ryman-Laikre model suggested a high contribution of hatchery-born scallops to the reproductive output of the wild population. Overall, the data suggest that the main objective of the seeding program, which is stock enhancement, is fulfilled. Moreover, gene flow from surrounding populations and/or the reproductive input of undetected sub-populations within the bay may buffer the Ryman-Laikre effect and ensure the retention of the local genetic variability. PMID:27353046

  14. De Novo Assembly and Characterization of Two Transcriptomes Reveal Multiple Light-Mediated Functions in the Scallop Eye (Bivalvia: Pectinidae)

    PubMed Central

    Pairett, Autum N.; Serb, Jeanne M.

    2013-01-01

    Background The eye has evolved across 13 separate lineages of molluscs. Yet, there have been very few studies examining the molecular machinary underlying eye function of this group, which is due, in part, to a lack of genomic resources. The scallop (Bivalvia: Pectinidae) represents a compeling molluscan model to study photoreception due to its morphologically novel and separately evolved mirror-type eye. We sequenced the adult eye transcriptome of two scallop species to: 1) identify the phototransduction pathway components; 2) identify any additional light detection functions; and 3) test the hypothesis that molluscs possess genes not found in other animal lineages. Results A total of 3,039 contigs from the bay scallop, Argopecten irradians and 26,395 contigs from the sea scallop, Placopecten magellanicus were produced by 454 sequencing. Targeted BLAST searches and functional annotation using Gene Ontology (GO) terms and KEGG pathways identified transcripts from three light detection systems: two phototransduction pathways and the circadian clock, a previously unrecognized function of the scallop eye. By comparing the scallop transcriptomes to molluscan and non-molluscan genomes, we discovered that a large proportion of the transcripts (7,776 sequences) may be specific to the scallop lineage. Nearly one-third of these contain transmembrane protein domains, suggesting these unannotated transcripts may be sensory receptors. Conclusions Our data provide the most comprehensive transcriptomic resource currently available from a single molluscan eye type. Candidate genes potentially involved in sensory reception were identified, and are worthy of further investigation. This resource, combined with recent phylogenetic and genomic data, provides a strong foundation for future investigations of the function and evolution of molluscan photosensory systems in this morphologically and taxonomically diverse phylum. PMID:23922823

  15. Association of myostatin variants with growth traits of Zhikong scallop ( Chlamys farreri)

    NASA Astrophysics Data System (ADS)

    Fu, Qiang; Guo, Huihui; Feng, Liying; Li, Xue; Zhang, Lingling; Wang, Shi; Hu, Xiaoli; Bao, Zhenmin

    2016-02-01

    Scallop is a popular sea food and an important aquaculture shellfish. Identification of genes and genetic variants relating to scallop growth could benefit high-yielding scallop breeding. Myostatin ( MSTN) is a conservative regulator of muscle growth, and has become one of the most important target genes for genetic improvement of the production of farmed animals. In this study, four single nucleotide polymorphisms (SNPs) were identified in the 5' flanking region of MSTN gene ( CfMSTN) in Zhikong scallop ( Chlamys farreri). The association of these SNPs with scallop growth traits, including shell length, shell height, body weight and striated muscle weight was analyzed. The SNP g-1162Gscallops showed significantly higher trait values than those of GT type, and the GG type individuals exhibited median values. On the contrary, significantly more CfMSTN transcripts were detected in the striated muscle of GT type scallops than in those of TT and GG type ones. Our results suggested that CfMSTN might regulate the scallop muscle growth negatively, and SNP g-1162Gscallop.

  16. 50 CFR 648.56 - Scallop research.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... description of methods of data collection and analysis; a discussion of results and any relevant conclusions... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Scallop research. 648.56 Section 648.56... Scallop Fishery § 648.56 Scallop research. (a) Annually, the Council and NMFS shall prepare and issue...

  17. JUVENILE BAY SCALLOP (ARGOPECTEN IRRADIANS) HABITAT PREFERENCES

    EPA Science Inventory

    Habitat quality and quantity are known to be important for maintaining populations of bay scallops (Argopecten irradians), but data linking habitat attributes to bay scallop populations are lacking. This information is essential to understand the role of habitat alteration in th...

  18. 50 CFR 648.56 - Scallop research.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... completion of scallop research projects approved pursuant to this section and the applicable NOAA grants... proposed research to scallop research priorities and/or management needs, project design, participants... each research project. Recipients may begin compensation fishing in open areas prior to approval of...

  19. 50 CFR 648.56 - Scallop research.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... completion of scallop research projects approved pursuant to this section and the applicable NOAA grants... proposed research to scallop research priorities and/or management needs, project design, participants... each research project. Recipients may begin compensation fishing in open areas prior to approval of...

  20. 50 CFR 648.56 - Scallop research.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... completion of scallop research projects approved pursuant to this section and the applicable NOAA grants... proposed research to scallop research priorities and/or management needs, project design, participants... each research project. Recipients may begin compensation fishing in open areas prior to approval of...

  1. 50 CFR 648.56 - Scallop research.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... completion of scallop research projects approved pursuant to this section and the applicable NOAA grants... proposed research to scallop research priorities and/or management needs, project design, participants... each research project. Recipients may begin compensation fishing in open areas prior to approval of...

  2. Hydrolysates from scallop and squid processing byproducts as specialty aquafeed ingredients

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Around 9,000 MT of squid (Loligo pealei) is landed annually in Rhode Island, USA, most of which is processed resulting in 40-50% unutilized byproducts (about 3,500 MT). On the other hand, the sea scallop (Placopecten magellanicus) resource off New England is currently at historic high levels of 22,7...

  3. Population Dynamics and Parasite Load of a Foraminifer on Its Antarctic Scallop Host with Their Carbonate Biomass Contributions.

    PubMed

    Hancock, Leanne G; Walker, Sally E; Pérez-Huerta, Alberto; Bowser, Samuel S

    2015-01-01

    We studied the population dynamics and parasite load of the foraminifer Cibicides antarcticus on its host the Antarctic scallop Adamussium colbecki from three localities differing by sea ice cover within western McMurdo Sound, Ross Sea, Antarctica: Explorers Cove, Bay of Sails and Herbertson Glacier. We also estimated CaCO3 biomass and annual production for both species. Cibicides populations varied by locality, valve type, and depth. Explorers Cove with multiannual sea ice had larger populations than the two annual sea ice localities, likely related to differences in nutrients. Populations were higher on Adamussium top valves, a surface that is elevated above the sediment. Depth did not affect Cibicides distributions except at Bay of Sails. Cibicides parasite load (the number of complete boreholes in Adamussium valves) varied by locality between 2% and 50%. For most localities the parasite load was < 20%, contrary to a previous report that ~50% of Cibicides were parasitic. The highest and lowest parasite load occurred at annual sea ice localities, suggesting that sea ice condition is not important. Rather, the number of adults that are parasitic could account for these differences. Cibicides bioerosion traces were categorized into four ontogenetic stages, ranging from newly attached recruits to parasitic adults. These traces provide an excellent proxy for population structure, revealing that Explorers Cove had a younger population than Bay of Sails. Both species are important producers of CaCO3. Cibicides CaCO3 biomass averaged 47-73 kg ha(-1) and Adamussium averaged 4987-6806 kg ha(-1) by locality. Annual production rates were much higher. Moreover, Cibicides represents 1.0-2.3% of the total host-parasite CaCO3 biomass. Despite living in the coldest waters on Earth, these species can contribute a substantial amount of CaCO3 to the Ross Sea and need to be incorporated into food webs, ecosystem models, and carbonate budgets for Antarctica. PMID:26186724

  4. Population Dynamics and Parasite Load of a Foraminifer on Its Antarctic Scallop Host with Their Carbonate Biomass Contributions

    PubMed Central

    Pérez-Huerta, Alberto; Bowser, Samuel S.

    2015-01-01

    We studied the population dynamics and parasite load of the foraminifer Cibicides antarcticus on its host the Antarctic scallop Adamussium colbecki from three localities differing by sea ice cover within western McMurdo Sound, Ross Sea, Antarctica: Explorers Cove, Bay of Sails and Herbertson Glacier. We also estimated CaCO3 biomass and annual production for both species. Cibicides populations varied by locality, valve type, and depth. Explorers Cove with multiannual sea ice had larger populations than the two annual sea ice localities, likely related to differences in nutrients. Populations were higher on Adamussium top valves, a surface that is elevated above the sediment. Depth did not affect Cibicides distributions except at Bay of Sails. Cibicides parasite load (the number of complete boreholes in Adamussium valves) varied by locality between 2% and 50%. For most localities the parasite load was < 20%, contrary to a previous report that ~50% of Cibicides were parasitic. The highest and lowest parasite load occurred at annual sea ice localities, suggesting that sea ice condition is not important. Rather, the number of adults that are parasitic could account for these differences. Cibicides bioerosion traces were categorized into four ontogenetic stages, ranging from newly attached recruits to parasitic adults. These traces provide an excellent proxy for population structure, revealing that Explorers Cove had a younger population than Bay of Sails. Both species are important producers of CaCO3. Cibicides CaCO3 biomass averaged 47-73 kg ha-1 and Adamussium averaged 4987-6806 kg ha-1 by locality. Annual production rates were much higher. Moreover, Cibicides represents 1.0-2.3% of the total host-parasite CaCO3 biomass. Despite living in the coldest waters on Earth, these species can contribute a substantial amount of CaCO3 to the Ross Sea and need to be incorporated into food webs, ecosystem models, and carbonate budgets for Antarctica. PMID:26186724

  5. Introduction, spat-rearing and experimental culture of bay scallop, Argopecten irradians lamarck

    NASA Astrophysics Data System (ADS)

    Zhang, Fusui; He, Yichao; Liu, Xiangsheng; Ma, Jianghu; Li, Shuying; Qi, Lingxin

    1991-06-01

    Bay scallops were introduced from the east coast of the U.S. into China to shorten the economic turn-over from 2 to 1 year. Parent scallops were carried to Qingdao on Dec. 20, 1982 and stocked in indoor tanks at controlled temperature and fed with a mixture of Phaeodictylum tricornutum, Pyramimonas sp. and Chlorella sp. They spawned on Jan. 26 of the next year. The larvae were reared at a temperature of 18 21°C and fed with Isochrysis galbana, Pyramimonas sp. and Chorella sp. In 4 weeks’ growing, the spats averaged 827 μm. They attained a height of 6.9 mm on May 9. In the middle of May, the seed scallops were transferred to Luoyuan Bay in Fujian Province, and Jiaozhou Bay, as well as the area off Taiping Jiao Cape, Qingdao, Shandong Province for experimental culture in plastic netcages suspended on a single line raft. Bay scallops cultured in Luoyuan Bay grew to an averaged shell height of 10.4 mm. In Jiaozhou Bay and the Taiping Jiao Cape culture area, they grew to 50 mm in average shell height (marketable size) and 26 g in average weight by late September; and attained 59 mm in average shell height (R. 39 75 mm) and 46 g in average weight in late December. The ovary and testis could be distinguished by color in August. In early September, eggs and sperms were collected for our laboratory where the second generation of seed scallops was successfully reared to suitable size for growing outdoor and breeding. This species can be harvested within a year after fertilization of the eggs, so we consider it suitable for culture in the Yellow Sea and East China Sea. This is the first reported successful introduction of Atlantic mollusks to the China Seas.

  6. Restoration Lessons Learned from Bay Scallop Habitat Models

    EPA Science Inventory

    Habitat quality and quantity are important factors to consider when restoring bay scallop (Argopecten irradians) populations; however, data linking habitat attributes to bay scallop populations are lacking. This information is essential to guide restoration efforts to reverse sc...

  7. Is Sexual Size Dimorphism Inherent in the Scallop Patinopecten yessoensis?

    PubMed Central

    Silina, Alla V.

    2016-01-01

    Studies on sexual size dimorphism in Pectinidae are limited. This work deals with the mobile long-lived scallop Patinopecten yessoensis, a common (fished and cultured) species in the subtidal benthos of the Sea of Japan. A previously developed method of age determination in P. yessoensis allowed me to compare the parameters of same aged males and females in scallop populations. The shell growth rates and sizes of both sexes were similar; therefore, it was only possible to visually identify the sex of live specimens during the breeding period (May-June). Statistical analyses showed female-biased dimorphism in the gonad weight for age groups that are >4 years old. Gonad weight (in the prespawning period) increased with age, until a threshold age was attained, which varied between populations; and then gonad weight remained virtually unchanged. The fecundity advantage hypothesis for P. yessoensis with group mating and external fertilization is at least partly realized by physiological mechanisms, which cause older females to have larger gonads than those of same aged males in the population in order to produce a larger brood. Gregarious settlement of this bivalve contributes to the reproductive success of the population so that the energetically costly ovaries may all be fertilized. PMID:27293980

  8. Effect of reproduction on escape responses and muscle metabolic capacities in the scallop Chlamys islandica Müller 1776.

    PubMed

    Brokordt; Himmelman; Guderley

    2000-08-30

    In scallops, gametogenesis leads to mobilization of glycogen and proteins from the adductor muscle towards the gonad. This mobilization is likely to diminish the metabolic capacities of the adductor muscle and thereby the scallops' escape response. We examined the escape response in terms of number of valve claps until exhaustion, rate of clapping and the recovery during and after valve closure in adult scallops, Chlamys islandica, sampled at different stages in the reproductive cycle (immature, mature, before and after spawning). In parallel, we measured muscle glycogen, protein and phosphoarginine contents, the oxidative capacity of mitochondria isolated from the adductor muscle and levels of muscle enzymes which are active during exercise and recovery. The number of claps (24-26), rate of clapping ( approximately 13 clapsmin(-1)) and phosphoarginine and arginine kinase levels were similar during the different reproductive stages. All immature scallops responded to restimulation immediately after opening their valves, while only 62% of mature, 82% of prespawned and 38% of spawned scallops responded. Immature animals completely recovered their initial swimming capacity within 4 h of opening their valves, but mature, prespawned and spawned scallops needed 18, 12 and 18 h, respectively. Overall phasic adductor muscle from mature, prespawned and spawned animals showed decreased glycogen phosphorylase, phosphofructokinase, pyruvate kinase (except for prespawned), octopine dehydrogenase and citrate synthase levels, a deterioration of the oxidative capacity of mitochondria and a marked decrease in glycogen content compared to immature scallops. Therefore, during gonadal maturation and spawning, C. islandica did not change its clapping capacity, but slowed its recuperation from exhausting burst exercise, both during and after valve closure, likely due to the decreased metabolic capacity of the adductor muscle. PMID:10960615

  9. Crystal Structure of a Phosphorylated Light Chain Domain of Scallop Smooth-Muscle Myosin

    SciTech Connect

    Kumar, V.S.; Robinson, H.; O-Neall-Hennessey, E.; Reshetnikova, L.; Brown, J. H.; Szent-Gyorgyi, A. G.; Cohen, C.

    2011-11-02

    We have determined the crystal structure of a phosphorylated smooth-muscle myosin light chain domain (LCD). This reconstituted LCD is of a sea scallop catch muscle myosin with its phosphorylatable regulatory light chain (RLC SmoA). In the crystal structure, Arg{sup 16}, an arginine residue that is present in this isoform but not in vertebrate smooth-muscle RLC, stabilizes the phosphorylation site. This arginine interacts with the carbonyl group of the phosphorylation-site serine in the unphosphorylated LCD (determined previously), and with the phosphate group when the serine is phosphorylated. However, the overall conformation of the LCD is essentially unchanged upon phosphorylation. This result provides additional evidence that phosphorylation of the RLC is unlikely to act as an on-switch in regulation of scallop catch muscle myosin.

  10. Physical Mechanisms of Glaze Ice Scallop Formations on Swept Wings

    NASA Technical Reports Server (NTRS)

    Vargas, Mario; Reshotko, Eli

    1998-01-01

    An experiment was conducted to understand the physical mechanisms that lead to the formation of scallops on swept wings. Icing runs were performed on a NACA 0012 swept wing tip at 45 deg, 30 deg, and 15 deg sweep angles. A baseline case was chosen and direct measurements of scallop height and spacing, castings, video data and close-up photographic data were obtained. The results showed the scallops are made of glaze ice feathers that grow from roughness elements that have reached a minimum height and are located beyond a given distance from the attachment line. This distance depends on tunnel conditions and sweep angle, and is the critical parameter in the formation of scallops. It determines if complete scallops, incomplete scallops or no scallops are going to be formed. The mechanisms of growth for complete and incomplete scallops were identified. The effect of velocity, temperature and LWC on scallop formation was studied. The possibility that cross flow instability may be the physical mechanism that triggers the growth of roughness elements into glaze ice feathers is examined.

  11. A synthesized mating pheromone component increases adult sea lamprey (Petromyzon marinus) trap capture in management scenarios

    USGS Publications Warehouse

    Johnson, Nicholas S.; Siefkes, Michael J.; Wagner, C. Michael; Dawson, Heather; Wang, Huiyong; Steeves, Todd; Twohey, Michael; Li, Weiming

    2013-01-01

    Application of chemical cues to manipulate adult sea lamprey (Petromyzon marinus) behavior is among the options considered for new sea lamprey control techniques in the Laurentian Great Lakes. A male mating pheromone component, 7a,12a,24-trihydroxy-3-one-5a-cholan-24-sulfate (3kPZS), lures ovulated female sea lamprey upstream into baited traps in experimental contexts with no odorant competition. A critical knowledge gap is whether this single pheromone component influences adult sea lamprey behavior in management contexts containing free-ranging sea lampreys. A solution of 3kPZS to reach a final in-stream concentration of 10-12 mol·L-1 was applied to eight Michigan streams at existing sea lamprey traps over 3 years, and catch rates were compared between paired 3kPZS-baited and unbaited traps. 3kPZS-baited traps captured significantly more sexually immature and mature sea lampreys, and overall yearly trapping efficiency within a stream averaged 10% higher during years when 3kPZS was applied. Video analysis of a trap funnel showed that the likelihood of sea lamprey trap entry after trap encounter was higher when the trap was 3kPZS baited. Our approach serves as a model for the development of similar control tools for sea lamprey and other aquatic invaders.

  12. HABITAT ASSESSMENT MODELS FOR BAY SCALLOP, ARGOPECTEN IRRADIANS

    EPA Science Inventory

    Bay scallops (Argopecten irradians) inhabit shallow subtidal habitats along the Atlantic coast of the United States and require settlement substrates, such as submerged aquatic vegetation (SAV), for their early juvenile stages. The short lifespan of bay scallops (1-2 yr) coupled...

  13. Steady as He Goes: At-Sea Movement of Adult Male Australian Sea Lions in a Dynamic Marine Environment

    PubMed Central

    Lowther, Andrew D.; Harcourt, Robert G.; Page, Bradley; Goldsworthy, Simon D.

    2013-01-01

    The southern coastline of Australia forms part of the worlds' only northern boundary current system. The Bonney Upwelling occurs every austral summer along the south-eastern South Australian coastline, a region that hosts over 80% of the worlds population of an endangered endemic otariid, the Australian sea lion. We present the first data on the movement characteristics and foraging behaviour of adult male Australian sea lions across their South Australian range. Synthesizing telemetric, oceanographic and isotopic datasets collected from seven individuals enabled us to characterise individual foraging behaviour over an approximate two year time period. Data suggested seasonal variability in stable carbon and nitrogen isotopes that could not be otherwise explained by changes in animal movement patterns. Similarly, animals did not change their foraging patterns despite fine-scale spatial and temporal variability of the upwelling event. Individual males tended to return to the same colony at which they were tagged and utilized the same at-sea regions for foraging irrespective of oceanographic conditions or time of year. Our study contrasts current general assumptions that male otariid life history strategies should result in greater dispersal, with adult male Australian sea lions displaying central place foraging behaviour similar to males of other otariid species in the region. PMID:24086338

  14. Fine-scale pathways used by adult sea lampreys during riverine spawning migrations

    USGS Publications Warehouse

    Holbrook, Christopher; Bergstedt, Roger A.; Adams, Noah S.; Hatton, Tyson; McLaughlin, Robert L

    2015-01-01

    Better knowledge of upstream migratory patterns of spawning Sea Lampreys Petromyzon marinus, an invasive species in the Great Lakes, is needed to improve trapping for population control and assessment. Although trapping of adult Sea Lampreys provides the basis for estimates of lake-wide abundance that are used to evaluate the Sea Lamprey control program, traps have only been operated at dams due to insufficient knowledge of Sea Lamprey behavior in unobstructed channels. Acoustic telemetry and radiotelemetry were used to obtain movement tracks for 23 Sea Lampreys in 2008 and 18 Sea Lampreys in 2009 at two locations in the Mississagi River, Ontario. Cabled hydrophone arrays provided two-dimensional geographic positions from acoustic transmitters at 3-s intervals; depth-encoded radio tag detections provided depths. Upstream movements occurred at dusk or during the night (2015–0318 hours). Sea Lampreys were closely associated with the river bottom and showed some preference to move near banks in shallow glide habitats, suggesting that bottom-oriented gears could selectively target adult Sea Lampreys in some habitats. However, Sea Lampreys were broadly distributed across the river channel, suggesting that the capture efficiency of nets and traps in open channels would depend heavily on the proportion of the channel width covered. Lack of vertical movements into the water column may have reflected lamprey preference for low water velocities, suggesting that energy conservation was more beneficial for lampreys than was vertical searching in rivers. Improved understanding of Sea Lamprey movement will assist in the development of improved capture strategies for their assessment and control in the Great Lakes.

  15. A HABITAT SUITABILITY INDEX FOR THE BAY SCALLOP ARGOPECTEN IRRADIANS

    EPA Science Inventory

    Platform Presentation at a Scientific Meeting. A survey of Lagoon Pond, Martha's Vineyard, MA, USA was conducted in September 2005 to determine the combination of habitat factors most highly correlated with bay scallop (Argopecten irradians) abundance. A stratified random samplin...

  16. De Novo Characterization of Japanese Scallop Mizuhopecten yessoensis Transcriptome and Analysis of Its Gene Expression following Cadmium Exposure

    PubMed Central

    Meng, Xiao-lin; Liu, Mei; Jiang, Ke-yong; Wang, Bao-jie; Tian, Xue; Sun, Shu-juan; Luo, Zuo-yong; Qiu, Chu-wen; Wang, Lei

    2013-01-01

    Background Japanese scallop has been cultured on a large-scale in China for many years. However, serious marine pollution in recent years has resulted in considerable loss to this industry. Moreover, due to the lack of genomic resources, limited research has been carried out on this species. To facilitate the understanding at molecular level immune and stress response mechanism, an extensive transcriptomic profiling and digital gene expression (DGE) database of Japanese scallop upon cadmium exposure was carried out using the Illumina sequencing platform. Results RNA-seq produced about 112 million sequencing reads from the tissues of adult Japanese scallops. These reads were assembled into 194,839 non-redundant sequences with open reading frame (ORF), of which 14,240 putative amino acid sequences were assigned biological function annotation and were annotated with gene ontology and eukaryotic orthologous group terms. In addition, we identified 720 genes involved in response to stimulus and 302 genes involved in immune-response pathways. Furthermore, we investigated the transcriptomic changes in the gill and digestive gland of Japanese scallops following cadmium exposure using a tag-based DGE system. A total of 7,556 and 3,002 differentially expressed genes were detected, respectively, and functionally annotated with KEGG pathway annotations. Conclusion This study provides a comprehensive transcripts sequence resource for the Japanese scallop and presents a survey of gene expression in response to heavy metal exposure in a non-model marine invertebrate via the Illumina sequencing platform. These results may contribute to the in-depth elucidation of the molecular mechanisms involved in bivalve responses to marine pollutants. PMID:23741332

  17. Antimicrobial characteristics of heated scallop shell powder and its application.

    PubMed

    Sawai, Jun

    2011-09-01

    Scallop shells are used to make food additives and plastering and paving materials. However, most of the shell is considered commercial waste. In scallop-harvesting districts, large numbers of shells are heaped near the seaside, which creates problems such as offensive odors and soil pollution from heavy metals that leach out of the viscera. Therefore, new applications for scallop shells need to be developed. The main component of scallop shells is calcium carbonate (CaCO(3)), which is converted to calcium oxide (CaO) when heated. Heated scallop shell powder (HSSP) possesses broad antimicrobial action against the vegetative cells of bacteria, spores, and fungi. HSSP applied to fresh vegetables and processed foods reduces the number of viable bacterial cells. The use of HSSP in food processing provides a source of minerals and prolongs the shelf life of foodstuffs. Moreover, reducing the amount of scallop shell waste would reduce the related pollution problem. This report is a review of the antibacterial activity of HSSP and its application for the control of microbes. PMID:21946319

  18. Farming the Sea

    ERIC Educational Resources Information Center

    Morgan, William

    1971-01-01

    Florida has initiated a training program in an entirely new dimension--Sea Farming. Presented is a description of the vocational agriculture program designed to teach propagation, cultivation, harvesting, marketing, and conservation practices related to production of oysters, shrimp, scallops, crabs, and fin fishes. (Editor/GB)

  19. Differential expression of CuZnSOD gene under low temperature stress in noble scallop Chlamys nobilis with different carotenoid content.

    PubMed

    Han, Jianqiao; Lu, Yeqing; Zheng, Huaiping; Liu, Helu; Deng, Huajuan; Zhang, Bo

    2016-07-01

    The noble scallop Chlamys nobilis belongs to a warm-water mollusk and has been cultured in the sea of southern China since 1980s'. However, accidents of massive mortality have often occurred during the winter, and one of the reasons could be accumulation of harmful reactive oxygen species caused by lower temperature. Carotenoids are well known for their anti-oxidant function. To investigate whether carotenoids do play a role in mollusks' antioxidant defense system under lower temperature stress, an acute lower temperature experiment was conducted by using two types of scallops: the orange with higher carotenoids content and the brown with lower carotenoids content. Their CuZnSOD gene was cloned, mRNA expression levels were determined, and SOD activity and carotenoids content were measured. The complete CuZnSOD cDNA consists of 1078 nucleotides with an open reading frame encoding 154 amino acid residues, which has high identity with that of its sister species Chlamys farreri. The mRNA expression levels in both the mantle and gill from the orange scallops were significantly higher (P < 0.05) than that of the brown ones, but the result was the opposite in the blood. SOD activity in the mantle and gill from the orange scallops was significantly higher than (P < 0.05) that from the brown ones. Further, significantly positive correlations were found among CuZnSOD gene transcript levels, SOD activity and total carotenoids content in the orange scallops. The present results suggested that carotenoids could play roles in antioxidant defense system by upregulating gene expression under lower temperature stress in the noble scallop. PMID:27033805

  20. Scallops skeletons as tools for accurate proxy calibration

    NASA Astrophysics Data System (ADS)

    Lorrain, A.; Paulet, Y.-M.; Chauvaud, L.; Dunbar, R.; Mucciarone, D.; Pécheyran, C.; Amouroux, D.; Fontugne, M.

    2003-04-01

    Bivalves skeletons are able to produce great geochemical proxies. But general calibration of those proxies are based on approximate time basis because of misunderstanding of growth rhythm. In this context, the Great scallop, Pecten maximus, appears to be a powerful tool as a daily growth deposit has been clearly identified for this species (Chauvaud et al, 1998; Lorrain et al, 2000), allowing accurate environmental calibration. Indeed, using this species, a date can be affiliated to each growth increment, and as a consequence environmental parameters can be closely compared (at a daily scale) to observed chemical and structural shell variations. This daily record provides an unequivocal basis to calibrate proxies. Isotopic (Delta-13C and Delta-15N) and trace element analysis (LA-ICP-MS) have been performed on several individuals and different years depending on the analysed parameter. Seawater parameters measured one meter above the sea-bottom were compared to chemical variations in the calcitic shell. Their confrontation showed that even with a daily basis for data interpretation, calibration is still a challenge. Inter-individual variations are found and correlations are not always reproducible from one year to the others. The first explanation could be an inaccurate appreciation of the proximate environment of the animal, notably the water-sediment interface could best represent Pecten maximus environment. Secondly, physiological parameters could be inferred for those discrepancies. In particular, calcification takes places in the extrapallial fluid, which composition might be very different from external environment. Accurate calibration of chemical proxies should consider biological aspects to gain better insights into the processes controlling the incorporation of those chemical elements. The characterisation of isotopic and trace element composition of the extrapallial fluid and hemolymph could greatly help our understanding of chemical shell variations.

  1. Blocking and guiding adult sea lamprey with pulsed direct current from vertical electrodes

    USGS Publications Warehouse

    Johnson, Nicholas S.; Thompson, Henry T.; Holbrook, Christopher M.; Tix, John A.

    2014-01-01

    Controlling the invasion front of aquatic nuisance species is of high importance to resource managers. We tested the hypothesis that adult sea lamprey (Petromyzon marinus), a destructive invasive species in the Laurentian Great Lakes, would exhibit behavioral avoidance to dual-frequency pulsed direct current generated by vertical electrodes and that the electric field would not injure or kill sea lamprey or non-target fish. Laboratory and in-stream experiments demonstrated that the electric field blocked sea lamprey migration and directed sea lamprey into traps. Rainbow trout (Oncorhynchus mykiss) and white sucker (Catostomus commersoni), species that migrate sympatrically with sea lamprey, avoided the electric field and had minimal injuries when subjected to it. Vertical electrodes are advantageous for fish guidance because (1) the electric field produced varies minimally with depth, (2) the electric field is not grounded, reducing power consumption to where portable and remote deployments powered by solar, wind, hydro, or a small generator are feasible, and (3) vertical electrodes can be quickly deployed without significant stream modification allowing rapid responses to new invasions. Similar dual-frequency pulsed direct current fields produced from vertical electrodes may be advantageous for blocking or trapping other invasive fish or for guiding valued fish around dams.

  2. Species-specific oligonucleotides and multiplex PCR for forensic discrimination of two species of scallops, Placopecten magellanicus and Chlamys islandica.

    PubMed

    Marshall, H D; Johnstone, K A; Carr, S M

    2007-03-22

    Characterization of DNA that remains in seafood products after skin, scales, and shells are removed is widely used in forensic species identification, however, ordinary methods may be prohibitively expensive or time-consuming if large sample series need to be discriminated. Forensic discrimination of two species of bivalves commercially harvested from the North Atlantic, sea scallops (Placopecten magellanicus) and Icelandic scallops (Chlamys islandica), was made by means of species-specific oligonucleotides (SSOs) in a multiplex polymerase chain reaction (PCR). The test is a simultaneous in vitro amplification of a portion of the mitochondrial Cytochrome Oxidase I locus with a PCR anchor primer for a sequence identical in both species, and two alternative SSOs that selectively amplify either a 619-bp in Placopecten or a 459-bp DNA fragment in Chlamys. Fragment size and thus species identity are determined directly by gel electrophoresis. In the forensic application, analysis of more than 900 scallops from a series of samples seized from two fishing vessels showed significantly variable proportions of the species from the closed and open fisheries (Placopecten versus Chlamys, respectively). The multiplex SSO test provides a direct means of forensic identification of large population sample series, without the necessity of secondary DNA sequencing, RFLP mapping, or fingerprinting, and can be adapted to other loci and species. PMID:16822630

  3. Genetic Differentiation between Natural and Hatchery Stocks of Japanese Scallop (Mizuhopecten yessoensis) as Revealed by AFLP Analysis

    PubMed Central

    Liu, Wei-Dong; Li, Hong-Jun; Bao, Xiang-Bo; Gao, Xiang-gang; Li, Yun-feng; He, Chong-Bo; Liu, Zhan-Jiang

    2010-01-01

    Japanese scallop (Mizuhopecten yessoensis) is a cold-tolerant bivalve that was introduced to China for aquaculture in 1982. In this study, amplified fragment length polymorphism (AFLP) markers were used to investigate levels of genetic diversity within M. yessoensis cultured stocks and compare them with wild populations. Six pairs of primer combinations generated 368 loci among 332 individuals, in four cultured and three wild populations. High polymorphism at AFLP markers was found within both cultured and wild M. yessoensis populations. The percentage of polymorphic loci ranged from 61.04% to 72.08%, while the mean heterozygosity ranged from 0.2116 to 0.2596. Compared with wild populations, the four hatchery populations showed significant genetic changes, such as lower expected heterozygosity and percentage of polymorphic loci, and smaller frequency of private alleles, all indicative of a reduction in genetic diversity. Some genetic structures were associated with the geographical distribution of samples; with all samples from Dalian and Japan being closely related, while the population from Russia fell into a distinct clade in the phylogenetic analysis. The genetic information derived from this study indicated that intentional or accidental release of selected Japanese scallops into natural sea areas might result in disturbance of local gene pools and loss of genetic variability. We recommend monitoring the genetic variability of selected hatchery populations to enhance conservation of natural Japanese scallop resources. PMID:21152310

  4. FISH mapping and identification of Zhikong scallop (Chlamys farreri) chromosomes.

    PubMed

    Zhang, Lingling; Bao, Zhenmin; Wang, Shi; Hu, Xiaoli; Hu, Jingjie

    2008-01-01

    Chromosome identification is the first step in genomic research of a species, but it remains a challenge in scallops. In the present study, fluorescence in situ hybridization (FISH) mapping of 19 fosmid clones was attempted and used for chromosome identification in Zhikong scallop (Chlamys farreri Jones et Preston, 1904). Data showed that 10 clones were successfully mapped, including 7 without and 3 with C ( 0 ) t-1 DNA. Among them, 2 represented multiple signals and made no contribution to chromosome identification. Karyotypic analysis and cohybridization indicated that the remaining 8 clones realized the identification of 8 chromosomes. All 10 clones were sequenced at both ends, which could be developed as sequence-tagged sites and used for the unification of the cytological and genetic linkage maps. This study shows that fosmid clones can benefit chromosome identification and will undoubtedly be useful for cytogenetic research in Zhikong scallop. PMID:17955291

  5. New method of posterior scallop augmentation for ischemic mitral regurgitation.

    PubMed

    Aoki, Masakazu; Ito, Toshiaki

    2015-03-01

    We report a new method of posterior middle scallop (P2) augmentation for ischemic mitral regurgitation to achieve deep coaptation. First, P2 was divided straight at the center and partially detached from the annulus in a reverse T shape. A narrow pentagon-shaped section of pericardium was sutured to the divided P2 and annular defect. The tip of the pentagon was attached directly to the papillary muscle, thus creating a very large P2 scallop. A standard-sized ring was placed. We adopted this technique in 2 patients with advanced ischemic cardiomyopathy, and no mitral regurgitation was observed during a 1-year follow-up. PMID:25742844

  6. Cloning of a big defensin gene and its response to Vibrio parahaemolyticus challenge in the noble scallop Chlamys nobilis (Bivalve: Pectinidae).

    PubMed

    Yang, Jianqing; Luo, Jiafu; Zheng, Huaiping; Lu, Yeqing; Zhang, Hongkuan

    2016-09-01

    The noble scallop Chlamys nobilis has been an important marine cultured bivalve in the Southern Sea of China for decades. However, large-scale mortality events often occurred during the scallop' cultivation. As one of AMPs (antimicrobial peptides), big defensin is an important component of the innate immunity against pathogenic microorganisms in invertebrates. In order to investigate whether the big defensin can play a role in the immune defense against pathogenic microorganisms in noble scallop, a big defensin gene from the hemocytes of Chlamys nobilis (CnBD) was cloned, and the mRNA level was measured after an acute Vibrio parahaemolyticus challenge of 36 h. The CnBD cDNA contains an open reading frame (ORF) of 381 bp encoding a peptide of 126 amino acids residues. The deduce amino acid sequence of CnBD shows a high similarity with that from Argopecten irradians and displays common features of big defensin, indicating that CnBD is a new member of the big defensin family. Compared with the control group, the relative mRNA level of CnBD was significantly up-regulated at 3, 24 and 36 h. The present result indicated that CnBD played an immune role against bacterial infection in noble scallop. PMID:27474446

  7. Conservation Genetics of the Scalloped Hammerhead Shark in the Pacific Coast of Colombia.

    PubMed

    Quintanilla, Sonia; Gómez, Alberto; Mariño-Ramírez, Camila; Sorzano, Carolina; Bessudo, Sandra; Soler, German; Bernal, Jaime E; Caballero, Susana

    2015-01-01

    Previous investigations of the population genetics of the scalloped hammerhead sharks (Sphyrna lewini) in the Eastern Tropical Pacific have lacked information about nursery areas. Such areas are key to promoting conservation initiatives that can protect young sharks from threats such as overfishing. Here, we investigated the genetic diversity, phylogeography, and connectivity of S. lewini found in 3 areas of Colombia's Pacific coast: around Malpelo Island and in 2 National Natural Parks on the Colombian Pacific mainland (Sanquianga and Ensenada de Utría). We analyzed mtDNA control region (CR) sequences and genotyped 15 microsatellite loci in 137 samples of adults and juveniles. The mtDNA analyses showed haplotypes shared between the Colombian Pacific individuals sampled in this investigation and other areas in the Eastern Tropical Pacific, the Indo-Pacific, and with sequences previously reported in Colombia (Buenaventura Port), as well as 4 unique haplotypes. Population assignment and paternity analyses detected 3 parent-offspring pairs between Malpelo and Sanquianga and 1 between Malpelo and Utría. These results indicate high genetic connectivity between Malpelo Island and the Colombian Pacific coast, suggesting that these 2 areas are nurseries for S. lewini. This is, to our knowledge, the first evidence of nursery areas identified for the scalloped hammerhead shark anywhere in the world. Additional conservation planning may be required to protect these nursery habitats of this endangered shark species. PMID:26245780

  8. A HABITAT SUITABILITY INDEX FOR THE BAY SCALLOP ARGOPECTEN IRRADIANS

    EPA Science Inventory

    Poster presentation at a scientific meeting. A survey of Lagoon Pond, Martha's Vineyard, MA, USA was conducted in September 2005 to determine the combination of habitat factors most highly correlated with the bay scallop Argopecten irradians) abundance. A stratified random samp...

  9. Olfactory-mediated stream-finding behavior of migratory adult sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Vrieze, L.A.; Bergstedt, R.A.; Sorensen, P.W.

    2011-01-01

    Stream-finding behavior of adult sea lamprey (Petromyzon marinus), an anadromous fish that relies on pheromones to locate spawning streams, was documented in the vicinity of an important spawning river in the Great Lakes. Untreated and anosmic migrating sea lampreys were implanted with acoustic transmitters and then released outside the Ocqueoc River. Lampreys swam only at night and then actively. When outside of the river plume, lampreys pursued relatively straight bearings parallel to the shoreline while making frequent vertical excursions. In contrast, when within the plume, lampreys made large turns and exhibited a weak bias towards the river mouth, which one-third of them entered. The behavior of anosmic lampreys resembled that of untreated lampreys outside of the plume, except they pursued a more northerly compass bearing. To locate streams, sea lampreys appear to employ a three-phase odor-mediated strategy that involves an initial search along shorelines while casting vertically, followed by river-water-induced turning that brings them close to the river's mouth, which they then enter using rheotaxis. This novel strategy differs from that of salmonids and appears to offer this poor swimmer adaptive flexibility and suggests ways that pheromonal odors might be used to manage this invasive species.

  10. Estimating total population size for adult female sea turtles: Accounting for non-nesters

    USGS Publications Warehouse

    Kendall, W.L.; Richardson, J.I.

    2008-01-01

    Assessment of population size and changes therein is important to sea turtle management and population or life history research. Investigators might be interested in testing hypotheses about the effect of current population size or density (number of animals per unit resource) on future population processes. Decision makers might want to determine a level of allowable take of individual turtles of specified life stage. Nevertheless, monitoring most stages of sea turtle life histories is difficult, because obtaining access to individuals is difficult. Although in-water assessments are becoming more common, nesting females and their hatchlings remain the most accessible life stages. In some cases adult females of a given nesting population are sufficiently philopatric that the population itself can be well defined. If a well designed tagging study is conducted on this population, survival, breeding probability, and the size of the nesting population in a given year can be estimated. However, with published statistical methodology the size of the entire breeding population (including those females skipping nesting in that year) cannot be estimated without assuming that each adult female in this population has the same probability of nesting in a given year (even those that had just nested in the previous year). We present a method for estimating the total size of a breeding population (including nesters those skipping nesting) from a tagging study limited to the nesting population, allowing for the probability of nesting in a given year to depend on an individual's nesting status in the previous year (i.e., a Markov process). From this we further develop estimators for rate of growth from year to year in both nesting population and total breeding population, and the proportion of the breeding population that is breeding in a given year. We also discuss assumptions and apply these methods to a breeding population of hawksbill sea turtles (Eretmochelys imbricata) from

  11. Impact of particulate pollutant metals on larval and adult bivalve molluscs

    SciTech Connect

    Gilbert, T.R.; Robinson, W.E. ); Morse, M.P. . Marine Science Lab.)

    1982-10-25

    Our investigations of the effects of pollutants on bivalve molluscs have continued with studies with in the following areas: bioaccumulation of trace metals in adult sea scallops exposed to dissolved and particulate forms of the metals, SEM/EDXA studies of phosphoritic concretions in the kidneys of adult sea scallops (Placopecten magellanicus), documentation of the normal embryonic and larval development, including shell formation, in surf clams (Spisula solidissima), evaluation of the toxicity of dissolved silver to the gametes and larvae of surf clams at several stages of development, and examination of the effects of turbid suspensions on the feeding efficiency of larval Mercenaria mercenaria. The overall goal of our work is twofold. First, we are striving to gain an understanding of the pathways by which metals are transported within bivalve molluscs. The production of metallothioneins and metal-rich inorganic concretions have been documented for a number of bivalves. The ways in which of metal-rich matrices in membrane-limited vesicles as an intermediate step, is one area of investigation. Second, we are examining the relative sensitivities of the gamete and of early life stages of these organisms to stresses induced by exposure to energy-related pollutants. 46 refs., 12 figs., 8 tabs.

  12. Maternal offloading of organochlorine contaminants in the yolk-sac placental scalloped hammerhead shark (Sphyrna lewini).

    PubMed

    Lyons, Kady; Adams, Douglas H

    2015-04-01

    Elasmobranchs are a group of animals that typically occupy upper trophic levels in food webs and have a propensity to accumulate high contaminant concentrations. To date, few studies have investigated maternal offloading processes in sharks, despite the fact that this process represents a substantial source of exposure for young sharks and is a significant pathway for contaminant redistribution within marine ecosystems. Comparable to mammalian systems, scalloped hammerhead sharks (Sphyrna lewini) utilize a yolk-sac placental strategy to nourish young in utero, which may allow females to transfer contaminants to young. Organic contaminants (PCBs and chlorinated pesticides) were measured in livers of both females and males from several age classes that were collected from U.S. Atlantic waters, including two near-term pregnant females and their embryos. Adult female hammerheads (n = 3) were found to have lower levels of PCBs compared to the younger, adult male (mean ± SD, 11.1 ± 1.0 vs. 22.8 μg g(-1) lw), but had substantially higher concentrations of pesticides (4.1 ± 0.9 vs. 1.9 μg g(-1) lw). Embryos from the two litters (n = 36) had similar levels of summed organic contaminant concentrations (4.6 ± 0.9 μg g(-1) lw) and pregnant females were estimated to offload approximately 0.03-2.3% of their hepatic contaminant load to offspring. While the potential health impacts of these transferred contaminants is unknown, this is the first study to demonstrate that scalloped hammerheads are exposed to a substantial amount of contaminants prior to birth and document maternal offloading of organochlorines in a pseudo-placental shark species. Therefore, future research should continue to investigate the potential adverse effects these contaminants have on elasmobranch physiology. PMID:25527298

  13. Subcritical hydrothermal treatment for the recovery of liquid fertilizer from scallop entrails.

    PubMed

    Hwang, In-Hee; Aoyama, Hiroya; Abe, Natsuki; Matsuo, Takayuki; Matsuto, Toshihiko

    2015-01-01

    Scallop entrails are organic wastes containing abundant proteins and minerals but are considered difficult to recycle because of high cadmium concentrations. In this work, the current problem of scallop entrails recycling was investigated and a subcritical hydrothermal treatment (SCHT) was examined for the recovery of liquid fertilizer from scallop entrails. Scallop entrails are mainly recycled for composting and feedstuff production. However, the dilution by mixing scallop entrails with other feed waste was the sole countermeasure to reduce the cadmium concentration of compost. For feedstuff production, whole product derived from scallop entrails was exported to other countries instead of domestic utilization. Temperature, retention time (RT) at given temperature, and liquid-to-solid (LS) ratio were examined as SCHT conditions for scallop entrails processing. The extraction ratio of each constituent mainly depends on the temperature rather than the RT or the LS ratio. Upon the SCHT of scallop entrails at 200°C, an RT of 20 min, and an LS ratio of 10, the extraction of fertilizer constituents such as nitrogen, phosphorus, and potassium from the liquid product was optimum, whereas the release of cadmium was suppressed. The concentrations of heavy metals in the liquid product obtained using the above-mentioned SCHT conditions were below the maximum permissible concentration stipulated by the Fertilizer Control Law. SCHT is considered to be a feasible recycling method for scallop entrails to recover fertilizer components with a concomitant separation of cadmium from the product. PMID:25409578

  14. Anatomical distribution of heavy metals in the scallop Pecten maximus.

    PubMed

    Saavedra, Y; Gonzalez, A; Blanco, J

    2008-11-01

    This paper studied the anatomical distribution of mercury (Hg), cadmium (Cd), lead (Pb), chromium (Cr), nickel (Ni), arsenic (As), silver (Ag), copper (Cu) and zinc (Zn) in the scallop Pecten maximus and the possible implications in terms of shellfish management. Six organs were analysed: mantle, gills, foot, digestive gland, kidney and gonad. On the basis of their anatomical distribution, two groups of metals were able to be distinguished: the first included Pb, Hg, Ni, Zn and Ag; and the second comprised the four other metals studied. The metals in the first group preferentially accumulated in the kidney (except for Pb), with generally much lower concentrations in the other organs. The metals in the second group accumulated mainly in the digestive gland. As and Cu were included in the second group, but they also had particular inter-organ distribution characteristics. Among the edible organs of the scallop only the adductor muscle contained important proportions of one metal, As (which is very likely accumulated as a non-toxic derivative). A selective evisceration of the metal rich non-edible organs may therefore be considered a reliable measure to be taken with a view to reduce the metal content of scallops used for human consumption. This could be especially relevant for Cd, which is accumulated in high concentrations in the digestive gland. PMID:19680841

  15. Differential Effects of Sex Pheromone Compounds on Adult Female Sea Lamprey (Petromyzon marinus) Locomotor Patterns.

    PubMed

    Walaszczyk, Erin J; Goheen, Benjamin B; Steibel, Juan Pedro; Li, Weiming

    2016-06-01

    Synchronization of male and female locomotor activity plays a critical role in ensuring reproductive success, especially in semelparous species. The goal of this study was to elucidate the effects of individual chemical signals, or pheromones, on the locomotor activity in the sea lamprey (Petromyzon marinus). In their native habitat, adult preovulated females (POF) and ovulated females (OF) are exposed to sex pheromone compounds that are released from spermiated males and attract females to nests during their migration and spawning periods. In this study, locomotor activity of individual POF and OF was measured hourly in controlled laboratory conditions using an automated video-tracking system. Differences in the activity between a baseline day (no treatment exposure) and a treatment day (sex pheromone compound or control exposure) were examined for daytime and nighttime periods. Results showed that different pheromone compound treatments affected both POF and OF sea lamprey (p < 0.05) but in different ways. Spermiated male washings (SMW) and one of its main components, 7α,12α,24-trihydroxy-5α-cholan-3-one 24 sulfate (3kPZS), decreased activity of POF during the nighttime. SMW also reduced activity in POF during the daytime. In contrast, SMW increased activity of OF during the daytime, and an additional compound found in SMW, petromyzonol sulfate (PZS), decreased the activity during the nighttime. In addition, we examined factors that allowed us to infer the overall locomotor patterns. SMW increased the maximum hourly activity during the daytime, decreased the maximum hourly activity during the nighttime, and reduced the percentage of nocturnal activity in OF. Our findings suggest that adult females have evolved to respond to different male compounds in regards to their locomotor activity before and after final maturation. This is a rare example of how species-wide chemosensory stimuli can affect not only the amounts of activity but also the overall locomotor

  16. Sleep apnea and oxygen saturation in adults at 2640 m above sea level☆

    PubMed Central

    Bazurto Zapata, Maria Angelica; Dueñas Meza, Elida; Jaramillo, Claudia; Maldonado Gomez, Dario; Torres Duque, Carlos

    2014-01-01

    Purpose To describe the SpO2 in wakefulness, sleep and during the apnea–hypopnea in adults living in Bogotá, located at 2640 m above sea level. Methods Descriptive observational study in adults referred for polysomnogram (PSG). A normal Apnea hypopnea index (AHI) was defined as ≤5 and obstructive sleep apnea (OSA) was classified as mild (AHI 5–15), moderate (AHI 15–30), and severe (AHI >30). T-test or ANOVA test for SpO2 differences between groups was used. Results 1799 patients, 33% women. 222 (12.8%) did not have OSA (normal IAH), 268 (14.9%) mild OSA, 315 (17.5%) moderate ,and 993 (55.2%) severe. In all cases a low SpO2 (SpO2<90%) was found. The SpO2 was lower when the AHI was higher, in wakefulness, in non-REM and in REM (p<0.001). For all grades of severity, SpO2 decreased significantly from wakefulness to non-REM sleep and to REM sleep (p<0.001). Patients with severe OSA had higher desaturation during wakefulness (85.2±6.6%), non-REM sleep (83.1±7.7%), REM sleep (78.8±10.2), and during events (75.1±9.1%). Conclusions Patients with OSA at 2640 m have nocturnal desaturation lower than 88%, which decreases with higher severity of OSA. The clinical impact of sleep disorders at this point may be greater than at sea level and should be studied. PMID:26483911

  17. Food utilization of adult flatfishes co-occurring in the Bohai Sea of China

    NASA Astrophysics Data System (ADS)

    Shuozeng, Dou

    Stomach contents were examined of 4527 adult individuals of 12 flatfish species collected during the 1982-1983 Bohai Sea Fisheries Resources Investigation. Their food habits, diet diversity, similarity of prey taxa, trophic niche breadth and diet overlap were systematically analysed. Ninety-seven prey species belonging to the Coelenterata, Nemertinea, Polychaeta, Mollusca, Crustacea, Echinodermata, Hemichordata and fish were found and five of them were considered to be principal prey for flatfishes: Alpheus japonicus, Oratosquilla oratoria, Alpheus distinguendus, Loligo japonicus and Crangon affinis. Among the flatfishes, Paralichthys olivaceus was piscivorous, whereas Pseudopleuronectes yokohamae and Pseudopleuronectes herzensteini both had polychaetes and molluscs as their main prey groups. Pleuronichthys cornutus was classified as a polychaete-mollusc eater, with a strong preference for crustaceans. Verasper variegatus, Cynoglossus semilaevis, Eopsetta grigorjewi and Cleisthenes herzensteini ate crustaceans. Kareius bicoloratus was classified as a mollusc-crustacean eater. Cynoglossus abbreviatus, Cynoglossus joyneri and Zebrias zebra were grouped as crustacean-fish eaters. However, Z. zebra also took polychaetes and C. abbreviatus and C. joyneri preyed on some molluscs. Trophic relationships among the flatfishes were complicated, but they occupied distinctive microhabitats in different seasons and selected their specific prey items, which was favourable to the stability of the flatfish community in the Bohai Sea.

  18. Measuring Energy Expenditure in Sub-Adult and Hatchling Sea Turtles via Accelerometry

    PubMed Central

    Halsey, Lewis G.; Jones, T. Todd; Jones, David R.; Liebsch, Nikolai; Booth, David T.

    2011-01-01

    Measuring the metabolic of sea turtles is fundamental to understanding their ecology yet the presently available methods are limited. Accelerometry is a relatively new technique for estimating metabolic rate that has shown promise with a number of species but its utility with air-breathing divers is not yet established. The present study undertakes laboratory experiments to investigate whether rate of oxygen uptake (o2) at the surface in active sub-adult green turtles Chelonia mydas and hatchling loggerhead turtles Caretta caretta correlates with overall dynamic body acceleration (ODBA), a derivative of acceleration used as a proxy for metabolic rate. Six green turtles (25–44 kg) and two loggerhead turtles (20 g) were instrumented with tri-axial acceleration logging devices and placed singly into a respirometry chamber. The green turtles were able to submerge freely within a 1.5 m deep tank and the loggerhead turtles were tethered in water 16 cm deep so that they swam at the surface. A significant prediction equation for mean o2 over an hour in a green turtle from measures of ODBA and mean flipper length (R2 = 0.56) returned a mean estimate error across turtles of 8.0%. The range of temperatures used in the green turtle experiments (22–30°C) had only a small effect on o2. A o2-ODBA equation for the loggerhead hatchling data was also significant (R2 = 0.67). Together these data indicate the potential of the accelerometry technique for estimating energy expenditure in sea turtles, which may have important applications in sea turtle diving ecology, and also in conservation such as assessing turtle survival times when trapped underwater in fishing nets. PMID:21829613

  19. Measuring energy expenditure in sub-adult and hatchling sea turtles via accelerometry.

    PubMed

    Halsey, Lewis G; Jones, T Todd; Jones, David R; Liebsch, Nikolai; Booth, David T

    2011-01-01

    Measuring the metabolic of sea turtles is fundamental to understanding their ecology yet the presently available methods are limited. Accelerometry is a relatively new technique for estimating metabolic rate that has shown promise with a number of species but its utility with air-breathing divers is not yet established. The present study undertakes laboratory experiments to investigate whether rate of oxygen uptake (VO2) at the surface in active sub-adult green turtles Chelonia mydas and hatchling loggerhead turtles Caretta caretta correlates with overall dynamic body acceleration (ODBA), a derivative of acceleration used as a proxy for metabolic rate. Six green turtles (25-44 kg) and two loggerhead turtles (20 g) were instrumented with tri-axial acceleration logging devices and placed singly into a respirometry chamber. The green turtles were able to submerge freely within a 1.5 m deep tank and the loggerhead turtles were tethered in water 16 cm deep so that they swam at the surface. A significant prediction equation for mean VO2 over an hour in a green turtle from measures of ODBA and mean flipper length (R(2) = 0.56) returned a mean estimate error across turtles of 8.0%. The range of temperatures used in the green turtle experiments (22-30 °C) had only a small effect on Vo₂. A VO2-ODBA equation for the loggerhead hatchling data was also significant (R(2) = 0.67). Together these data indicate the potential of the accelerometry technique for estimating energy expenditure in sea turtles, which may have important applications in sea turtle diving ecology, and also in conservation such as assessing turtle survival times when trapped underwater in fishing nets. PMID:21829613

  20. 76 FR 40674 - Fisheries of the Exclusive Economic Zone Off Alaska; Scallops

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-11

    ... prevent overfishing in the target fishery for weathervane scallops. Implementing these measures would... estimate of spawning biomass for weathervane scallops, the overfishing level (OFL) is specified as the MSY...-Stevens Act relative to preventing overfishing and establishing an ABC and ACL. The following is a...

  1. Using a System Level Approach to Bay Scallop Enhancement and Management

    EPA Science Inventory

    Within the last twenty years total harvests of bay scallops (Argopecten irradians) have dwindled in the southern New England Region. Management of scallop populations has been underway on Martha’s Vineyard Island to provide the public with a fishery, and have included a com...

  2. A model for autumn pelagic distribution of adult female polar bears in the Chukchi Seas, 1987-1994

    USGS Publications Warehouse

    Durner, G.M.; Douglas, D.C.; Nielson, R.M.; Amstrup, Steven C.

    2006-01-01

    We made predictions of polar bear (Ursus maritimus) autumn distribution in the Chukchi Sea with a Resource Selection Function (RSF) developed from 1198 satellite radio-collar locations on 124 adult female polar bears, 1987 – 1994. The RSF was created to assist in an aerial survey design for polar bears proposed by the U.S. Fish and Wildlife Service. The RSF was based on bathymetry and daily sea ice covariates extracted from passive microwave satellite imagery within the pelagic region > 25 km from shore. The RSF indicated that polar bears selected habitats with intermediate amounts (~50%) of ice cover in close proximity to higher ice concentrations, and over relatively shallow waters. The RSF showed good predictive abilities for the years of its construct, worked best in October, and was robust to inter-annual variability. When evaluated with recent (1997 – 2005) data, the RSF performed well for October and November but poorly in September. This loss of predictive abilities appeared to be related to recent changes in habitat due to longer melt seasons and younger sea ice, and testing the retrospective model with a small sample of recent polar bears locations from a limited region of the Chukchi Sea. Contemporary applications of this RSF must consider three factors that could limit its utility: 1) 2 different sea ice phenology; 2) distributions of males and sub-adults; and 3) occupancy in nearshore habitats.

  3. The quality of great scallop (Pecten maximus) sperm after thawing.

    PubMed

    Suquet, Marc; Gourtay, Clémence; Donval, Anne; Le Goïc, Nelly; Quere, Claudie; Malo, Florent; Le Grand, Jaqueline; Ratiskol, Dominique; Mingant, Christian; Fauvel, Christian

    2016-04-01

    Most publications devoted to the cryopreservation of mollusc sperm have focused on the definition of technical protocols, avoiding the description of sperm quality after thawing. The present study investigated the effects of cryopreservation on sperm quality in the great scallop. Wild scallop were fished during the natural spawning period and conditioned in the hatchery before use. Sperm samples were obtained after intragonadal injection of serotonin and cryopreserved using a previously published protocol. Sperm quality was assessed using a panel of four parameters: sperm motility characteristics, using a computer assisted sperm analysis plugin with Image J, intracellular ATP content using an ATP-Lite kit, sperm integrity, using flow cytometry and sperm morphology, using transmission electron microscopy. For each parameter, fresh (control) and thawed spermatozoa were compared. A significant decrease of both the percentage of motile spermatozoa (reduction: 75%) and sperm swimming speed (86%) were observed for thawed sperm compared with fresh sperm. The percentage of living spermatozoa, as assessed using flow cytometry, was significantly lower for thawed sperm (72.4±2.5%) compared with fresh sperm (86.4±1.1). However, no significant difference of intracellular sperm ATP content was observed between fresh and thawed sperm. Post thawing, while some spermatozoa showed little or no morphological differences compared with fresh sperm, others had undergone drastic changes, including swelling of the plasma membrane, structural alterations of the chromatin and damage to mitochondria. In conclusion, the descriptive parameters studied in the present work showed that the quality of thawed great scallop sperm was lower than that of fresh cells but was still sufficient for use in aquaculture programs and sperm cryobanking for this species. PMID:26944486

  4. In Vivo Administration of Scallop GnRH-Like Peptide Influences on Gonad Development in the Yesso Scallop, Patinopecten yessoensis

    PubMed Central

    Nagasawa, Kazue; Oouchi, Hitoshi; Itoh, Naoki; Takahashi, Keisuke G.; Osada, Makoto

    2015-01-01

    Existing research on the role of gonadotropin-releasing hormone (GnRH) in bivalve reproduction is inadequate, even though a few bivalve GnRH orthologs have been cloned. The objective of this paper was to elucidate the in vivo effect of GnRH administration in Yesso scallop reproduction. We performed in vivo administration of scallop GnRH (py-GnRH) synthetic peptide into the developing gonad, and analyzed its effect on gonad development for 6 weeks during the reproductive season. The resulting sex ratio in the GnRH administered (GnRH(+)) group might be male biased, whereas the control (GnRH(-)) group had an equal sex ratio throughout the experiment. The gonad index (GI) of males in the GnRH(+) group increased from week 2 to 24.8% at week 6. By contrast the GI of the GnRH(-) group peaked in week 4 at 16.6%. No significant difference was seen in female GI between the GnRH(+) and GnRH(-) groups at any sampling point. Oocyte diameter in the GnRH(+) group remained constant (about 42–45 μm) throughout the experiment, while in the GnRH(-) group it increased from 45 to 68 μm i.e. normal oocyte growth. The number of spermatogonia in the germinal acini of males in the GnRH(+) group increased from week 4 to 6. Hermaphrodites appeared in the GnRH(+) group in weeks 2 and 4. Their gonads contained many apoptotic cells including oocytes. In conclusion, this study suggests that py-GnRH administration could have a potential to accelerate spermatogenesis and cause an inhibitory effect on oocyte growth in scallops. PMID:26030928

  5. Characterization, expression and function analysis of DAX1 gene of scallop ( Chlamys farreri jones and preston 1904) during its gametogenesis

    NASA Astrophysics Data System (ADS)

    Li, Hailong; Liu, Jianguo; Huang, Xiaoting; Wang, Dan; Zhang, Zhifeng

    2014-08-01

    DAX1, a member of nuclear receptor superfamily, has a function in the sex determination and gonadal differentiation of several vertebrate species. However, little information about DAX1 of invertebrates is available. Here we cloned a homolog of scallop ( Chlamys farreri Jones and Preston 1904) dax1, Cf-dax1, and determined its expression characteristics at mRNA and protein levels. The cDNA sequence of Cf-dax1 was 2093 bp in length, including 1404 bp open reading frame (ORF) encoding 467 amino acids. Unlike those of vertebrates, no conserved LXXLL-related motif was found in the putative DNA binding region of Cf-DAX1. Fluorescence in situ hybridization showed that Cf-dax1 located on the short arm of a pair of subtelocentric chromosomes. Tissue distribution analysis using semi-quantitative RT-PCR revealed that Cf-dax1 expressed widely in adult scallop tissues, with the highest expression level found in adductor muscle, moderate level in mantle, gill and testis, and low level in kidney, ovary and hepatopancreas. The result of quantitative real-time PCR indicated that the expression of Cf-dax1 was significantly higher ( P<0.05) in testis than in ovary at the same stage, showing a sex-dimorphic expression pattern. Furthermore, immunohistochemical detection found that Cf-DAX1 mainly located in spermatogonia and spermatocytes of testis and in oogonia and oocytes of ovary, implying that DAX1 may involve in gametogenesis of bivalves.

  6. The mobilisation of sediment and benthic infauna by scallop dredges.

    PubMed

    O'Neill, F G; Robertson, M; Summerbell, K; Breen, M; Robinson, L A

    2013-09-01

    We present the results of experiments to assess the immediate impact of scallop dredging on the seabed sediment and on the inhabiting infauna. The passage of the scallop dredge is shown to homogenise the seabed, flattening sand ripples. The turbulent wake entrains up to the equivalent of a 1 mm layer of sediment per unit of swept width, although an analysis of the finer particles material implies that the suspended silt material must originate from depths of at least 10 mm. The species most abundant in the sediment plume either swim actively in the water column or are found in, or on, the upper layers of the substrate, whereas those most abundant in core samples taken from the sediment, but not present in the net samples, are almost all tube-building or deep burrowing. The vertical stratification of sediment concentration and of animal numbers in the water column suggests that even if some of these species respond actively to the presence of the dredge, once entrained, they are transported more or less passively in the same way as the larger sediment particles. There was no difference between the core samples taken before or after towing suggesting that animals mobilised by the dredge resettle in the tow path. Our analysis does not provide any information regarding the fate of these animals. PMID:23871519

  7. Electroreception in juvenile scalloped hammerhead and sandbar sharks.

    PubMed

    Kajiura, Stephen M; Holland, Kim N

    2002-12-01

    The unique head morphology of sphyrnid sharks might have evolved to enhance electrosensory capabilities. The 'enhanced electroreception' hypothesis was tested by comparing the behavioral responses of similarly sized carcharhinid and sphyrnid sharks to prey-simulating electric stimuli. Juvenile scalloped hammerhead sharks Sphyrna lewini and sandbar sharks Carcharhinus plumbeus oriented to dipole electric fields from the same maximum distance (approximately 30 cm) and thus demonstrated comparable behavioral-response thresholds (<1 nV cm(-1)). Despite the similarity of response threshold, the orientation pathways and behaviors differed for the two species. Scalloped hammerheads typically demonstrated a pivot orientation in which the edge of the cephalofoil closest to the dipole remained stationary while the shark bent its trunk to orient to the center of the dipole. By contrast, sandbars swam in a broader arc towards the center of the dipole. The different orientation patterns are attributed to the hydrodynamic properties of the cephalofoil, which enables the hammerheads to execute sharp turns at high speed. The greater trunk width of the sandbar sharks prevented them from demonstrating the same degree of flexibility. Therefore, although the sphyrnid head morphology does not appear to confer a greater sensitivity to prey-simulating dipole electric fields, it does provide (1). a greater lateral search area, which may increase the probability of prey encounter, and (2). enhanced maneuverability, which may aid in prey capture. PMID:12409487

  8. Feet, heat and scallops: what is the cost of anthropogenic disturbance in bivalve aquaculture?

    PubMed

    Robson, Anthony A; Halsey, Lewis G; Chauvaud, Laurent

    2016-03-01

    The effects of unnatural disturbances on the behaviour and energetics of animals are an important issue for conservation and commercial animal production. Biologging enables estimation of the energy costs of these disturbances, but not specifically the effect these costs have on growth; a key outcome measure for animal farming enterprises. We looked at how natural and anthropogenically induced activity and energy expenditure of king scallops Pecten maximus varies with temperature. These data were then used to model growth time of king scallops reared in an aquaculture facility under different temperatures and anthropogenic disturbance levels. The scallops exhibited a typical total metabolic rate (MR)-temperature curve, with a peak reached at a middling temperature. The percentage of their total MR associated with spinning and swimming, behavioural responses to disturbance, was considerable. Interestingly, as temperature increased, the activity MR associated with a given level of activity decreased; a hitherto unreported relationship in any species. The model results suggest there is a trade-off in the ambient temperature that should be set by hatcheries between the optimal for scallop growth if completely undisturbed versus mitigating against the energy costs elicited by anthropogenic disturbance. Furthermore, the model indicates that this trade-off is affected by scallop size. Aquaculture facilities typically have controls to limit the impact of human activities, yet the present data indicate that hatcheries may be advised to consider whether more controls could further decrease extraneous scallop behaviours, resulting in enhanced scallop yields and improved financial margins. PMID:27069659

  9. Feet, heat and scallops: what is the cost of anthropogenic disturbance in bivalve aquaculture?

    PubMed Central

    Halsey, Lewis G.; Chauvaud, Laurent

    2016-01-01

    The effects of unnatural disturbances on the behaviour and energetics of animals are an important issue for conservation and commercial animal production. Biologging enables estimation of the energy costs of these disturbances, but not specifically the effect these costs have on growth; a key outcome measure for animal farming enterprises. We looked at how natural and anthropogenically induced activity and energy expenditure of king scallops Pecten maximus varies with temperature. These data were then used to model growth time of king scallops reared in an aquaculture facility under different temperatures and anthropogenic disturbance levels. The scallops exhibited a typical total metabolic rate (MR)–temperature curve, with a peak reached at a middling temperature. The percentage of their total MR associated with spinning and swimming, behavioural responses to disturbance, was considerable. Interestingly, as temperature increased, the activity MR associated with a given level of activity decreased; a hitherto unreported relationship in any species. The model results suggest there is a trade-off in the ambient temperature that should be set by hatcheries between the optimal for scallop growth if completely undisturbed versus mitigating against the energy costs elicited by anthropogenic disturbance. Furthermore, the model indicates that this trade-off is affected by scallop size. Aquaculture facilities typically have controls to limit the impact of human activities, yet the present data indicate that hatcheries may be advised to consider whether more controls could further decrease extraneous scallop behaviours, resulting in enhanced scallop yields and improved financial margins. PMID:27069659

  10. [An adult case of visceral leishmaniasis in a province of Black-Sea region, Turkey].

    PubMed

    Oztoprak, Nefise; Aydemir, Hande; Pişkin, Nihal; Seremet Keskin, Ayşegül; Araslı, Mehmet; Gökmen, Ayla; Celebi, Güven; Külekçi Uğur, Aslıhan; Taylan Özkan, Ayşegül

    2010-10-01

    Visceral leishmaniasis (VL) which is a chronic disease caused by the protozoon, Leishmania, occurs widely worldwide and it is widespread in most of the countries in the Mediterranean basin. The infection which is transmitted by a sandfly (Phlebotomus) vector, has a prolonged incubation period and insidious onset. VL generally affects children and may be fatal if not treated. In this report, a 31 years old male patient, who was the first adult VL case from Zonguldak (a province located at western Black-Sea region of Turkey) was presented. He was admitted to the hospital with two-months history of fever, chills, sweating and weight loss. There was no history of travel outside the city nor insect bites, however, he indicated that there would be unnoticed sandfly bites since sandflies were very common in the coal mines he worked. His physical examination revealed body temperatue of 39.2°C and hepatosplenomegaly, while laboratory findings yielded anemia, leucopenia, hypoalbuminemia and hypergamaglobulinemia. Erythrocyte sedimentation rate was 62 mm/h, C-reactive protein was 113 mg/L and liver transaminases were 2 to 5 folds higher than the reference values. The only pathological finding was hepatosplenomegaly in the abdominal ultrasound and computerized tomography. He was further examined to rule out infections with similar signs and symptoms, connective tissue diseases and malignancies and all were found negative. Hypercellular bone marrow were detected in the aspiration material. Bone marrow smears, bone marrow samples inoculated in NNN medium and serum samples of the patient were sent to the reference parasitology laboratory of Refik Saydam National Public Health Agency for evaluation in terms of VL. The diagnosis was confirmed by the detection of Leishmania IgG titer as 1/512 with in-house indirect immunofluorescence antibody test, by positivite rK39 Dipstick (InBios, USA) test and by the observation of Leishmania amastigote forms in the bone marrow smears. Bone

  11. Predictors of Successful Quitting among Thai Adult Smokers: Evidence from ITC-SEA (Thailand) Survey

    PubMed Central

    Jampaklay, Aree; Borland, Ron; Yong, Hua-Hie; Sirirassamee, Buppha; Fotuhi, Omid; Fong, Geoffrey T.

    2015-01-01

    This study uses longitudinal data from the International Tobacco Control Southeast Asia (ITC-SEA Thailand) survey to explore patterns and predictors of successful quitting among Thai adult smokers as a function of time quit. A cohort of a representative sample of 2000 smokers was surveyed four times from 2005 to 2009. A sample of 1533 individuals provided data for at least one of the reported analyses. Over the four years of follow-up, 97% made attempts to quit. Outcomes were successful quitting/relapse: (a) quit attempts of at least one month (short-term relapse, 43%) (57% remaining quit); (b) surviving at least six months (medium-term) (31%); (c) relapse between one and six months (45%); (d) having continuously quit between Waves 3 and 4 (sustained abstinence) (14%); and (e) relapse from six months on (44%) compared to those who continuously quit between Waves 3 and 4 (56%). Predictors for early relapse (<1 month) differ from longer-term relapse. Age was associated with reduced relapse over all three periods, and was much stronger for longer periods of abstinence. Cigarette consumption predicted relapse for short and medium terms. Self-assessed addiction was predictive of early relapse, but reversed to predict abstinence beyond six months. Previous quit history of more than one week was predictive of early abstinence, but became unrelated subsequently. Self-efficacy was strongly predictive of abstinence in the first month but was associated with relapse thereafter. Some determinants of relapse change with time quit, but this may be in somewhat different to patterns found in the West. PMID:26404335

  12. Ingestion of domoic acid and its impact on king scallop ( Pecten maximus, Linnaeus 1758)

    NASA Astrophysics Data System (ADS)

    Liu, Hui; Kelly, Maeve S.; Campbell, Dirk A.; Dong, Shuanglin; Zhu, Jianxin; Wang, Sufeng

    2007-04-01

    A simple method for spiking formulated feed with domoic acid (DA) was developed in this study. DA feed was prepared by mixing 0.15 mL 100 μg mL-1 DA with 0.1 g formulated feed, and drying the mixture at room temperature for 2h. The prepared DA feed contained 0.19 pg DA per particle. Of the added DA, 46.72% was retained in the feed. Relatively high DA retention (about 50%) was recorded after DA feed was soaked in water for 2h. Exposure to DA feed for 7 d did not cause the increase of tissue DA level of adult king scallop ( Pecten maximus) significantly in 60 d. The increase of their gonad index after DA exposure was not significantly different from the control. No significant change in DA level was found in spermary, ovary or fertilized eggs after DA exposure. These results indicated that DA excretion may be more efficient than DA accumulation under the current experimental conditions, and the mechanism of domoic acid incorporation in P. maximus may involve intracellular biotransformation.

  13. Habitat Characteristics Predicting Distribution and Abundance Patterns of Scallops in D’Entrecasteaux Channel, Tasmania

    PubMed Central

    Mendo, Tania; Lyle, Jeremy M.; Moltschaniwskyj, Natalie A.; Tracey, Sean R.; Semmens, Jayson M.

    2014-01-01

    Habitat characteristics greatly influence the patterns of distribution and abundance in scallops, providing structure for the settlement of spat and influencing predation risk and rates of survival. Establishing scallop-habitat relationships is relevant to understanding the ecological processes that regulate scallop populations and to managing critical habitats. This information is particularly relevant for the D’Entrecasteaux Channel, south-eastern Tasmania (147.335 W, 43.220 S), a region that has supported significant but highly variable scallop production over many years, including protracted periods of stock collapse. Three species of scallops are present in the region; the commercial scallop Pecten fumatus, the queen scallop Equichlamys bifrons, and the doughboy scallop Mimachlamys asperrima. We used dive surveys and Generalized Additive Modelling to examine the relationship between the distribution and abundance patterns of each species and associated habitat characteristics. The aggregated distribution of each species could be predicted as a function of sediment type and species-specific habitat structural components. While P. fumatus was strongly associated with finer sediments and E. bifrons with coarse grain sediments, M. asperrima had a less selective association, possibly related to its ability to attach on a wide range of substrates. Other habitat characteristics explaining P. fumatus abundance were depth, Asterias amurensis abundance, shell and macroalgae cover. Equichlamys bifrons was strongly associated with macroalgae and seagrass cover, whereas M. asperrima abundance was greatly explained by sponge cover. The models define a set of relationships from which plausible hypotheses can be developed. We propose that these relationships are mediated by predation pressure as well as the specific behavioural characteristics of each species. The findings also highlight the specific habitat characteristics that are relevant for spatial management and

  14. Habitat characteristics predicting distribution and abundance patterns of scallops in D'Entrecasteaux Channel, Tasmania.

    PubMed

    Mendo, Tania; Lyle, Jeremy M; Moltschaniwskyj, Natalie A; Tracey, Sean R; Semmens, Jayson M

    2014-01-01

    Habitat characteristics greatly influence the patterns of distribution and abundance in scallops, providing structure for the settlement of spat and influencing predation risk and rates of survival. Establishing scallop-habitat relationships is relevant to understanding the ecological processes that regulate scallop populations and to managing critical habitats. This information is particularly relevant for the D'Entrecasteaux Channel, south-eastern Tasmania (147.335 W, 43.220 S), a region that has supported significant but highly variable scallop production over many years, including protracted periods of stock collapse. Three species of scallops are present in the region; the commercial scallop Pecten fumatus, the queen scallop Equichlamys bifrons, and the doughboy scallop Mimachlamys asperrima. We used dive surveys and Generalized Additive Modelling to examine the relationship between the distribution and abundance patterns of each species and associated habitat characteristics. The aggregated distribution of each species could be predicted as a function of sediment type and species-specific habitat structural components. While P. fumatus was strongly associated with finer sediments and E. bifrons with coarse grain sediments, M. asperrima had a less selective association, possibly related to its ability to attach on a wide range of substrates. Other habitat characteristics explaining P. fumatus abundance were depth, Asterias amurensis abundance, shell and macroalgae cover. Equichlamys bifrons was strongly associated with macroalgae and seagrass cover, whereas M. asperrima abundance was greatly explained by sponge cover. The models define a set of relationships from which plausible hypotheses can be developed. We propose that these relationships are mediated by predation pressure as well as the specific behavioural characteristics of each species. The findings also highlight the specific habitat characteristics that are relevant for spatial management and habitat

  15. Is an Apicomplexan Parasite Responsible for the Collapse of the Iceland Scallop (Chlamys islandica) Stock?

    PubMed Central

    Kristmundsson, Árni; Erlingsdóttir, Ásthildur; Freeman, Mark A.

    2015-01-01

    Due to the total and unexpected collapse of the Iceland scallop, Chlamys islandica, stocks around Iceland during the 2000s, a commercial fishing ban has been imposed on this valuable resource since 2003. Following the initial identification of an apicomplexan parasite in the scallops, a long-term surveillance program was established to evaluate the effect of the parasite on the population. The infections were highly prevalent in all shell sizes throughout the study. However, the parasite only impacts mature scallops where they cause severe macroscopic changes, characterized by an extensively diminished and abnormally coloured adductor muscle. A highly significant relationship was observed between infection intensity and gonad and adductor muscle indices. The first four years of the study, were characterized by high infection intensity and very poor condition of the adductor muscle and gonads, whilst during subsequent years, infections gradually decreased and the condition of the scallops improved. Histopathological changes were restricted to the presence of apicomplexan zoites which were widely distributed, causing varying degrees of pathology in all organs. In heavy infections, muscular and connective tissues were totally necrotized, destroying significant parts of numerous organs, especially the adductor muscle, digestive gland and gonads. The progression of the disease was in good synchrony with the mortality rates and the subsequent decline observed in the scallop stock and recruitment indices. Our findings strongly suggest that the apicomplexan parasite played a major role in the collapse of the Iceland scallop stock in Breidafjordur. In addition to causing mortality, the infections significantly impact gonad development which contributes further to the collapse of the stock in the form of lower larval recruitment. Furthermore, compelling evidence exists that this apicomplexan pathogen is causing serious disease outbreaks in other scallop populations. Similar

  16. Body pool and synthesis of ascorbic acid in adult sea lamprey (Petromyzon marinus): An agnathan fish with gulonolactone oxidase activity

    PubMed Central

    Moreau, Régis; Dabrowski, Konrad

    1998-01-01

    Although many vertebrates can synthesize ascorbic acid (vitamin C), it is still unclear from the evolutionary perspective when the ability to synthesize the vitamin first appeared in the animal kingdom and how frequently the trait has been lost. We report here ascorbic acid biosynthesis ability in sea lamprey (Petromyzon marinus) which represent the most ancient vertebrate lineage examined thus far for presence of gulonolactone oxidase, the enzyme catalyzing the terminal step in biosynthesis of vitamin C. This finding supports the view that the ancestors of living vertebrates were not scurvy prone and that the loss of gulonolactone oxidase activity subsequently occurred several times in vertebrate phylogeny. Adult sea lamprey allocate significant amounts of ascorbic acid to the gonads to guaranty high-quality gametes. Tissue stores of ascorbate were maintained by de novo synthesis (1.2–1.3 mg of ascorbic acid/300-g sea lamprey per day at 15°C) while sea lamprey fast during spawning migration. We estimate that the in vivo daily renewal rate of ascorbate is 4–5% of the whole-body ascorbate pool based on measurement of its biosynthesis and concentration in the whole animal. PMID:9707638

  17. Scallops show that muscle metabolic capacities reflect locomotor style and morphology.

    PubMed

    Tremblay, Isabelle; Guderley, Helga E

    2014-01-01

    Although all scallops swim using their adductor muscle to close their valves, scallop species differ considerably in how they use their muscle during escape responses, in parallel with the striking interspecific differences in shell morphology. This provides an excellent opportunity to study links between muscle metabolic capacities and animal performance. We found that the capacity for anaerobic glycolysis and aerobic metabolism, as well as phosphoarginine levels in the phasic adductor muscle, differ with escape response strategy. Phosphoarginine contents were high in species that rely on phasic contractions (Amusium balloti, Placopecten magellanicus, and Pecten fumatus). Arginine kinase activities reflect reliance on rapid initial bursts of phasic contractions. Scallops that maintain their valves in a closed position for prolonged periods (P. fumatus, Mimachlamys asperrima, and Crassadoma gigantea) have high activities of enzymes of anaerobic glycolysis in their phasic adductor muscle. Myosin ATPase activity was lower in the nonswimming scallop, C. gigantea, than in swimming scallops. The different patterns and roles of swimming are reflected in interspecific differences in the biochemical attributes of the phasic adductor muscle. These patterns suggest coevolution of muscle metabolic capacities, patterns of adductor muscle use, and shell morphology in scallops. PMID:24642541

  18. Production of L-lactic Acid from Biomass Wastes Using Scallop Crude Enzymes and Novel Lactic Acid Bacterium

    NASA Astrophysics Data System (ADS)

    Yanagisawa, Mitsunori; Nakamura, Kanami; Nakasaki, Kiyohiko

    In the present study, biomass waste raw materials including paper mill sludge, bamboo, sea lettuce, and shochu residue (from a distiller) and crude enzymes derived from inedible and discarded scallop parts were used to produce L-lactic acid for the raw material of biodegradable plastic poly-lactic acid. The activities of cellulase and amylase in the crude enzymes were 22 and 170units/L, respectively, and L-lactic acid was produced from every of the above mentioned biomass wastes, by the method of liquid-state simultaneous saccharification and fermentation (SSF) . The L-lactic acid concentrations produced from sea lettuce and shochu residue, which contain high concentration of starch were 3.6 and 9.3g/L, respectively, and corresponded to greater than 25% of the conversion of glucans contained in these biomass wastes. Furthermore, using the solid state SSF method, concentrations as high as 13g/L of L-lactic acid were obtained from sea lettuce and 26g/L were obtained from shochu residue.

  19. Daytime avoidance of chemosensory alarm cues by adult sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Di Rocco, Richard; Belanger, Cowan; Imre, István; Brown, Grant; Johnson, Nicholas S.

    2014-01-01

    Sea lamprey (Petromyzon marinus) avoid damage-released and predator chemosensory cues at night, but their response to these cues during the day is unknown. Here, we explored (i) whether sea lamprey avoid these cues during the day and (ii) the effect of water temperature on the avoidance of chemosensory alarm cues in two diurnal laboratory experiments. We hypothesized that daytime activity would be temperature-dependent and that only sea lamprey vulnerable to predation (i.e., not hiding) would behaviourally respond to chemosensory alarm cues. Ten groups of ten sea lamprey were exposed to one of a variety of potential chemosensory cues. The experiments were conducted over a range of temperatures to quantify the effect of temperature on avoidance behaviour. Consistent with our hypothesis, a higher proportion of animals were active during daytime as water temperature increased. Moving sea lamprey showed an avoidance response to 2-phenylethylamine (a compound found in mammalian urine) and human saliva once water temperatures had risen to mean (±SD) = 13.7 (±1.4) °C. Resting and hiding sea lamprey did not show an avoidance response to any of the experimental stimuli.

  20. Regulation of scallop myosin by the regulatory light chain depends on a single glycine residue.

    PubMed Central

    Jancso, A; Szent-Györgyi, A G

    1994-01-01

    Specific Ca2+ binding and Ca2+ activation of ATPase activity in scallop myosin require a regulatory light chain (RLC) from regulated (molluscan or vertebrate smooth) myosin; hybrids containing vertebrate skeletal RLCs do not bind Ca2+ and their ATPase activity is inhibited. Chimeras between scallop and chicken skeletal RLCs restore Ca2+ sensitivity to RLC-free myosin provided that residues 81-117 are derived from scallop. Six mutants (R90M, A94K, D98P, N105K, M116Q, and G117C) were generated by replacing amino acids of the scallop RLC with the corresponding skeletal RLC residues in positions conserved in either regulated or nonregulated myosins. Ca2+ binding was abolished by a G117C and a G117A mutation; however, these mutants have a decreased affinity for the heavy chain. None of the other mutations affected RLC function. Replacement of the respective cysteine with glycine in the skeletal RLC has markedly changed the regulatory properties of the molecule. The single cysteine to glycine mutation conferred to this light chain the ability to restore Ca2+ binding and regulated ATPase activity, although Ca2+ activation of the actin-activated ATPase was lower than with scallop RLC. The presence of amino acids other than glycine at this position in vertebrate skeletal myosin RLCs may explain why these are not fully functional in the scallop system. The results are in agreement with x-ray crystallography data showing the central role of G117 in stabilizing the Ca(2+)-binding site of scallop myosin. Images PMID:8090720

  1. In Utero Domoic Acid Toxicity: A Fetal Basis to Adult Disease in the California Sea Lion (Zalophus californianus)

    PubMed Central

    Ramsdell, John S.; Zabka, Tanja S.

    2008-01-01

    California sea lions have been a repeated subject of investigation for early life toxicity, which has been documented to occur with increasing frequency from late February through mid-May in association with organochlorine (PCB and DDT) poisoning and infectious disease in the 1970’s and domoic acid poisoning in the last decade. The mass early life mortality events result from the concentrated breeding grounds and synchronization of reproduction over a 28 day post partum estrus cycle and 11 month in utero phase. This physiological synchronization is triggered by a decreasing photoperiod of 11.48 h/day that occurs approximately 90 days after conception at the major California breeding grounds. The photoperiod trigger activates implantation of embryos to proceed with development for the next 242 days until birth. Embryonic diapause is a selectable trait thought to optimize timing for food utilization and male migratory patterns; yet from the toxicological perspective presented here also serves to synchronize developmental toxicity of pulsed environmental events such as domoic acid poisoning. Research studies in laboratory animals have defined age-dependent neurotoxic effects during development and windows of susceptibility to domoic acid exposure. This review will evaluate experimental domoic acid neurotoxicity in developing rodents and, aided by comparative allometric projections, will analyze potential prenatal toxicity and exposure susceptibility in the California sea lion. This analysis should provide a useful tool to forecast fetal toxicity and understand the impact of fetal toxicity on adult disease of the California sea lion. PMID:18728728

  2. Individual variation in feeding habitat use by adult female green sea turtles (Chelonia mydas): are they obligately neritic herbivores?

    PubMed

    Hatase, Hideo; Sato, Katsufumi; Yamaguchi, Manami; Takahashi, Kotaro; Tsukamoto, Katsumi

    2006-08-01

    Satellite telemetry and stable isotope analysis were used to confirm that oceanic areas (where water depths are >200 m) are alternative feeding habitats for adult female green sea turtles (Chelonia mydas), which have been thought to be obligate herbivores in neritic areas (where depths are <200 m). Four females were tagged with satellite transmitters and tracked during post-nesting periods from Ogasawara Islands, Japan. Three females migrated to neritic habitats, while transmissions from another female ceased in an oceanic habitat. The overall mean nighttime dive depths during oceanic swimming periods in two females were <20 m, implying that the main function of their nighttime dives were resting with neutral buoyancy, whereas the means in two other females were >20 m, implying that they not only rested, but also foraged on macroplankton that exhibit diel vertical migration. Comparisons of stable carbon and nitrogen isotope ratios between 89 females and the prey items in a three-source mixing model estimated that 69% of the females nesting on Ogasawara Islands mainly used neritic habitats and 31% mainly used oceanic habitats. Out of four females tracked by satellite, two females were inferred from isotope ratios to be neritic herbivores and the two others oceanic planktivores. Although post-nesting movements for four females were not completely consistent with the inferences from isotope ratios, possibly due to short tracking periods (28-42 days), their diving behaviors were consistent with the inferences. There were no relationships between body size and the two isotope ratios, indicating a lack of size-related differences in feeding habitat use by adult female green turtles, which was in contrast with loggerhead sea turtles (Caretta caretta). These results and previous findings suggest that ontogenetic habitat shifts by sea turtles are facultative, and consequently, their life histories are polymorphic. PMID:16683139

  3. Pup Vibrissae Stable Isotopes Reveal Geographic Differences in Adult Female Southern Sea Lion Habitat Use during Gestation

    PubMed Central

    Baylis, Alastair M. M.; Kowalski, Gabriele J.; Voigt, Christian C.; Orben, Rachael A.; Trillmich, Fritz; Staniland, Iain J.; Hoffman, Joseph I.

    2016-01-01

    Individuals within populations often differ substantially in habitat use, the ecological consequences of which can be far reaching. Stable isotope analysis provides a convenient and often cost effective means of indirectly assessing the habitat use of individuals that can yield valuable insights into the spatiotemporal distribution of foraging specialisations within a population. Here we use the stable isotope ratios of southern sea lion (Otaria flavescens) pup vibrissae at the Falkland Islands, in the South Atlantic, as a proxy for adult female habitat use during gestation. A previous study found that adult females from one breeding colony (Big Shag Island) foraged in two discrete habitats, inshore (coastal) or offshore (outer Patagonian Shelf). However, as this species breeds at over 70 sites around the Falkland Islands, it is unclear if this pattern is representative of the Falkland Islands as a whole. In order to characterize habitat use, we therefore assayed carbon (δ13C) and nitrogen (δ15N) ratios from 65 southern sea lion pup vibrissae, sampled across 19 breeding colonies at the Falkland Islands. Model-based clustering of pup isotope ratios identified three distinct clusters, representing adult females that foraged inshore, offshore, and a cluster best described as intermediate. A significant difference was found in the use of inshore and offshore habitats between West and East Falkland and between the two colonies with the largest sample sizes, both of which are located in East Falkland. However, habitat use was unrelated to the proximity of breeding colonies to the Patagonian Shelf, a region associated with enhanced biological productivity. Our study thus points towards other factors, such as local oceanography and its influence on resource distribution, playing a prominent role in inshore and offshore habitat use. PMID:27304855

  4. Pup Vibrissae Stable Isotopes Reveal Geographic Differences in Adult Female Southern Sea Lion Habitat Use during Gestation.

    PubMed

    Baylis, Alastair M M; Kowalski, Gabriele J; Voigt, Christian C; Orben, Rachael A; Trillmich, Fritz; Staniland, Iain J; Hoffman, Joseph I

    2016-01-01

    Individuals within populations often differ substantially in habitat use, the ecological consequences of which can be far reaching. Stable isotope analysis provides a convenient and often cost effective means of indirectly assessing the habitat use of individuals that can yield valuable insights into the spatiotemporal distribution of foraging specialisations within a population. Here we use the stable isotope ratios of southern sea lion (Otaria flavescens) pup vibrissae at the Falkland Islands, in the South Atlantic, as a proxy for adult female habitat use during gestation. A previous study found that adult females from one breeding colony (Big Shag Island) foraged in two discrete habitats, inshore (coastal) or offshore (outer Patagonian Shelf). However, as this species breeds at over 70 sites around the Falkland Islands, it is unclear if this pattern is representative of the Falkland Islands as a whole. In order to characterize habitat use, we therefore assayed carbon (δ13C) and nitrogen (δ15N) ratios from 65 southern sea lion pup vibrissae, sampled across 19 breeding colonies at the Falkland Islands. Model-based clustering of pup isotope ratios identified three distinct clusters, representing adult females that foraged inshore, offshore, and a cluster best described as intermediate. A significant difference was found in the use of inshore and offshore habitats between West and East Falkland and between the two colonies with the largest sample sizes, both of which are located in East Falkland. However, habitat use was unrelated to the proximity of breeding colonies to the Patagonian Shelf, a region associated with enhanced biological productivity. Our study thus points towards other factors, such as local oceanography and its influence on resource distribution, playing a prominent role in inshore and offshore habitat use. PMID:27304855

  5. Tetraploid induction by inhibiting mitosis I in scallop Chlamys farreri

    NASA Astrophysics Data System (ADS)

    Yang, Hui-Ping; Guo, Xi-Ming; Chen, Zai-Zhong; Wang, Yong-Ping

    1999-12-01

    Tetraploid induction was carried out by inhibiting mitosis I in fertilized eggs of Chlamys farreri. Mitosis I was blocked with cold shock (5 7°C), Cytochalasin B (0.75 mg/L) and 6-dimethylaminopurine (6-DMAP) (60 75 mg/L) when 60% fertilized eggs released polar body II at 20°C. At 4-cells embryo stage, the ploidy was determined by counting chromosome number. In control groups, most embryos were diploids (72.22%) and aneuploids (24.78%). In Cytochalasin B, cold shock and 6-DMAP treated groups, tetraploids were respectively 10.51%, 4.08%, and 13.34%; aneuploids were 43.10%, 35.93% and 29.16%, and triploids were 7.84%, 8.52% and 18.33%. At D-larva stage, ploidy was determined by flow cytometry (FCM). The ploidy analysis of day 2 larvae showed diploids in control group and also in three treated groups. Juvenile scallops (0.2 0.3cm) which were harvested in two control groups and two CB treated groups were all diploids through checking ploidy individually by FCM.

  6. Expression and Function of Scalloped During Drosophila Development

    PubMed Central

    Guss, Kirsten A.; Benson, Michael; Gubitosi, Nicholas; Brondell, Karrie; Broadie, Kendal; Skeath, James B.

    2013-01-01

    Background The scalloped (sd) and vestigial (vg) genes function together in Drosophila wing development. Little is known about sd protein (SD) expression during development, or whether sd and vg interact in other developing tissues. To begin to address these questions, we generated an anti-SD antibody. Results During embryogenesis, SD is expressed in both central and peripheral nervous systems, and the musculature. SD is also expressed in developing flight appendages. Despite SD expression herein, the peripheral nervous system, musculature, and dorsal limb primordia appeared generally normal in the absence of sd function. SD is also expressed in subsets of ventral nerve cord cells, including neuroblast 1–2 descendants and ventral unpaired median motor neurons (mVUMs). While sd function is not required to specify these neurons, it is necessary for the correct innervation of somatic muscles by the mVUMs. We also show that SD and VG are co-expressed in overlapping and distinctive subsets of cells in embryonic and larval tissues. Conclusions We describe the full breadth of SD expression during Drosophila embryogenesis, and identify a requirement for sd function in a subset of motor neurons. This work provides the necessary foundation for functional studies regarding the roles of sd during Drosophila development. PMID:23389965

  7. Kinematics and critical swimming speed of juvenile scalloped hammerhead sharks

    PubMed

    Lowe

    1996-01-01

    Kinematics and critical swimming speed (Ucrit) of juvenile scalloped hammerhead sharks Sphyrna lewini were measured in a Brett-type flume (635 l). Kinematic parameters were also measured in sharks swimming in a large pond for comparison with those of sharks swimming in the flume. Sharks in the flume exhibited a mean Ucrit of 65±11 cm s-1 (± s.d.) or 1.17±0.21 body lengths per second (L s-1), which are similar to values for other species of sharks. In both the flume and pond, tailbeat frequency (TBF) and stride length (LS) increased linearly with increases in relative swimming speed (Urel=body lengths traveled per second). In the flume, tailbeat amplitude (TBA) decreased with increasing speed whereas TBA did not change with speed in the pond. Differences in TBF and LS between sharks swimming in the flume and the pond decreased with increases in Urel. Sharks swimming at slow speeds (e.g. 0.55 L s-1) in the pond had LS 19 % longer and TBF 21 % lower than sharks in the flume at the same Urel. This implies that sharks in the flume expended more energy while swimming at comparable velocities. Comparative measurements of swimming kinematics from sharks in the pond can be used to correct for effects of the flume on shark swimming kinematics and energetics. PMID:9320537

  8. Movement of scallop myosin on Nitella actin filaments: regulation by calcium.

    PubMed Central

    Vale, R D; Szent-Gyorgyi, A G; Sheetz, M P

    1984-01-01

    In order to determine if Ca2+ regulates scallop myosin movement on actin, we have measured motility of scallop myosin along actin filaments using a direct visual assay. This procedure consists of covalently linking myosin to 1-micron beads and pipetting them onto a parallel array of actin filaments located on the cytoplasmic face of a Nitella internodal cell. In the absence of Ca2+, scallop myosin-coated beads exhibit no directed motion; however, in the presence of pCa2+ of greater than 5.84, these beads undergo linear translocations with average velocities of 2.0 micron/s. This Ca2+ -sensitive motility requires the presence of regulatory light chains on the scallop myosin. Removal of regulatory light chains with 10 mM EDTA produces a "desensitized" myosin, no longer sensitive to Ca2+, which moves at rates of 0.09-0.3 micron in the presence or absence of Ca2+. Readdition of regulatory light chains to preparations of desensitized myosin once again confers Ca2+-sensitive motility. The Ca2+ dependence of scallop-myosin motility shows a sharp transition, consistent with the Ca2+ activation sensitivity of the actin-activated ATPase. Furthermore, relative rates of movement of calcium-regulated myosins from various molluscan species are consistent with their respective rates of ATP hydrolysis. Thus, myosin motility along actin filaments provides a sensitive and direct assay of myosin activity and is suitable for studying myosin regulation. PMID:6238334

  9. Genomic Characterization of Interspecific Hybrids between the Scallops Argopecten purpuratus and A. irradians irradians

    PubMed Central

    Hu, Liping; Huang, Xiaoting; Mao, Junxia; Wang, Chunde; Bao, Zhenmin

    2013-01-01

    The Peruvian scallop (Argopecten purpuratus) has been introduced to China and has successfully been hybridized with the bay scallop (A. irradians irradians). The F1 hybrids of these two scallops exhibited a large increase in production traits and some other interesting new characteristics. To understand the genetic basis of this heterosis, nuclear gene and partial mtDNA sequences, and genomic in situ hybridization (GISH) were employed to analyze the genomic organization of the hybrids. Amplification of the ribosomal DNA internal transcribed spacer (ITS) showed that the parental ITS sequences were present in all the hybrid individuals, illustrating that the hybrid offspring inherited nuclear DNA from both parents. Sequence analyses of the ITS region further confirmed that the hybrids harbored alleles from their parents; some recombinant variants were also detected, which revealed some alterations in the nuclear genetic material of the hybrids. The analysis of mitochondrial 16S rDNA showed that the hybrids possessed sequences that were identical to the 16S rDNA of the female parents, proving a matrilineal inheritance of mitochondrial genes in scallops. In addition, GISH clearly discriminated between the parental chromosomes and indicated a combination of haploid genomes of duplex parents in the hybrids. The genetic analyses in our study illustrated that the F1 hybrids inherited nuclear material from both parents and cytoplasmic genetic material maternally, and some variations occurred in the genome, which might contribute to a further understanding of crossbreeding and heterosis in scallop species. PMID:23620828

  10. Quantification of the indirect effects of scallop dredge fisheries on a brown crab fishery.

    PubMed

    Öndes, Fikret; Kaiser, Michel J; Murray, Lee G

    2016-08-01

    This study aimed to describe the characteristics of the by-catch of Cancer pagurus in king scallop dredges in the Isle of Man, and to determine the damage, immediate mortality and estimated mortality during fishing seasons associated with scallop dredges. Based on dredge surveys, spatial and seasonal variations were observed, with the highest number of crabs found off the west coast of the Isle of Man in the autumn when berried females crabs were most frequently caught. In general, female crabs comprised 84% of the catch. The damage levels of crabs was high with 45% of crabs recorded as crushed or dead or with severe damage, whilst 24% of crabs exhibited missing limbs. Estimates of the potential mortality associated with scallop dredging led to a lower and upper estimate of possible crab by-catch mortality of 15t and 24t respectively which represented 3.0-4.8% of the commercial landings of brown crab for the Isle of Man. Heaviest mortalities of crabs occurred in autumn to the west of the Isle of Man when female berried crabs move offshore into deeper water. The use of a temporary and spatially restricted scallop dredging closure could provide a simple solution to mitigate additional crab mortality in the event that scallop dredging increased beyond current levels in the future. PMID:27268589

  11. Swimming performance, metabolic rates, and their correlates in the Iceland scallop Chlamys islandica.

    PubMed

    Tremblay, Isabelle; Guderley, Helga E; Frechette, Marcel

    2006-01-01

    The dramatic escape response of some scallops is modified by reproductive investment and by acclimation temperature. Despite considerable knowledge of the physiology of the escape response, functional links between escape response performance, organismal rates of oxygen uptake, and tissue metabolic capacities are little known. We measured oxygen consumption rates (standard, maximal, and aerobic scope), escape behavior (initial and repeat performance), tissue mass, condition index, protein content, and tissue metabolic capacities in the Iceland scallop Chlamys islandica to examine links between these parameters. Postexercise oxygen consumption rates were positively linked to contraction rate (repeat test) and to pyruvate kinase activity in the adductor muscle but negatively linked to digestive gland wet mass. Swimming behavior was mainly related to activity of glycolytic enzymes, and enzymatic activities were related to anatomic parameters. Scallop behavior and physiology change with size, both within our samples and on a larger scale. Small scallops showed more intense swimming activity and had higher arginine kinase activities but lower glycolytic enzyme activities in their adductor muscle than larger scallops. This corresponds to the ontogenetic change in susceptibility to predation and in habitat use observed in C. islandica. PMID:17041870

  12. Integration of Next Generation Sequencing and EPR Analysis to Uncover Molecular Mechanism Underlying Shell Color Variation in Scallops

    PubMed Central

    Sun, Xiujun; Liu, Zhihong; Zhou, Liqing; Wu, Biao; Dong, Yinghui; Yang, Aiguo

    2016-01-01

    The Yesso scallop Patinopecten yessoensis displays polymorphism in shell colors, which is of great interest for the scallop industry. To identify genes involved in the shell coloration, in the present study, we investigate the transcriptome differences by Illumina digital gene expression (DGE) analysis in two extreme color phenotypes, Red and White. Illumina sequencing yields a total of 62,715,364 clean sequence reads, and more than 85% reads are mapped into our previously sequenced transcriptome. There are 25 significantly differentially expressed genes between Red and White scallops. EPR (Electron paramagnetic resonance) analysis has identified EPR spectra of pheomelanin and eumelanin in the red shells, but not in the white shells. Compared to the Red scallops, the White scallops have relatively higher mRNA expression in tyrosinase genes, but lower expression in other melanogensis-associated genes. Meantime, the relatively lower tyrosinase protein and decreased tyrosinase activity in White scallops are suggested to be associated with the lack of melanin in the white shells. Our findings highlight the functional roles of melanogensis-associated genes in the melanization process of scallop shells, and shed new lights on the transcriptional and post-transcriptional mechanisms in the regulation of tyrosinase activity during the process of melanin synthesis. The present results will assist our molecular understanding of melanin synthesis underlying shell color polymorphism in scallops, as well as other bivalves, and also help the color-based breeding in shellfish aquaculture. PMID:27563719

  13. Integration of Next Generation Sequencing and EPR Analysis to Uncover Molecular Mechanism Underlying Shell Color Variation in Scallops.

    PubMed

    Sun, Xiujun; Liu, Zhihong; Zhou, Liqing; Wu, Biao; Dong, Yinghui; Yang, Aiguo

    2016-01-01

    The Yesso scallop Patinopecten yessoensis displays polymorphism in shell colors, which is of great interest for the scallop industry. To identify genes involved in the shell coloration, in the present study, we investigate the transcriptome differences by Illumina digital gene expression (DGE) analysis in two extreme color phenotypes, Red and White. Illumina sequencing yields a total of 62,715,364 clean sequence reads, and more than 85% reads are mapped into our previously sequenced transcriptome. There are 25 significantly differentially expressed genes between Red and White scallops. EPR (Electron paramagnetic resonance) analysis has identified EPR spectra of pheomelanin and eumelanin in the red shells, but not in the white shells. Compared to the Red scallops, the White scallops have relatively higher mRNA expression in tyrosinase genes, but lower expression in other melanogensis-associated genes. Meantime, the relatively lower tyrosinase protein and decreased tyrosinase activity in White scallops are suggested to be associated with the lack of melanin in the white shells. Our findings highlight the functional roles of melanogensis-associated genes in the melanization process of scallop shells, and shed new lights on the transcriptional and post-transcriptional mechanisms in the regulation of tyrosinase activity during the process of melanin synthesis. The present results will assist our molecular understanding of melanin synthesis underlying shell color polymorphism in scallops, as well as other bivalves, and also help the color-based breeding in shellfish aquaculture. PMID:27563719

  14. Distribution and evolution of scalloped terrain in the southern hemisphere, Mars

    NASA Astrophysics Data System (ADS)

    Zanetti, Michael; Hiesinger, Harald; Reiss, Dennis; Hauber, Ernst; Neukum, Gerhard

    2010-04-01

    Scalloped depressions are a unique martian surface morphology found in the northern and southern hemisphere latitude-dependent dust and ice-rich surface mantles. These features exhibit a distinct asymmetric north-south slope profile, characterized by steep pole-facing scarps, flat floors and gentle equator-facing slopes. We examined High Resolution Stereo Camera (HRSC) images of the southern hemisphere to determine their longitudinal distribution, which revealed that a majority of scalloped terrain is located in the region of the southern wall of the Hellas Basin and northern Malea Planum. A detailed map of this area was produced where scallops were found to contour the southern wall of the basin, and where the ice-rich mantle was seen to be thickest. Scalloped terrain is concentrated along the topographic highs near the Amphitrites and Peneus Paterae and areal extent and depth decreases with increasing depth into the basin. We also examined existing hypothesis for the formation and evolution of scalloped depressions using High Resolution Imaging Science Experiment (HiRISE) images and data from the Thermal Emission Imaging System-Infrared (THEMIS-IR) and the Thermal Emission Spectrometer (TES). Our approach provides regional context for the development of scalloped terrains within the southern hemisphere, and offers detailed evidence of scallop depressions forming around small cracks, presumably caused by thermal contraction. Morphometric measurements show that scalloped depressions can be as much as 40 m deep, with typical depths of between 10 and 20 m. Our observations of scallop formation and development in the southern hemisphere support a solar-insolation model proposed by previous researchers (e.g. [Morgenstern, A., Hauber, E., Reiss, D., van Gasselt, S., Grosse, G., Schirrmeister, L., 2007. J. Geophys. Res. 112, CiteID E06010; Lefort, A., Russell, P.S., Thomas, N., McEwen, A.S., Dundas, C.M., Kirk, R.L., 2009a. J. Geophys. Res. 114, E04005; Lefort, A

  15. Cloning, expression, and tissue localisation of prolactin in adult sea bream (Sparus aurata).

    PubMed

    Santos, C R; Brinca, L; Ingleton, P M; Power, D M

    1999-04-01

    A major action of prolactin (PRL) in teleost fish is the maintenance of hydromineral balance in euryhaline species in fresh water. The function of PRL in marine teleosts is less certain and unlike euryhaline teleosts, such as tilapia and salmon, there is relatively little information about protein or gene structure. Associated with studies to determine potential functions of PRL, pituitary prolactin cDNA has been cloned and sequenced from sea bream (Sparus aurata), a marine teleost. The sequence obtained spanned 1349 bp and contained an open reading frame encoding a protein of 212 amino acids composed of a putative signal peptide of 24 residues and a mature protein of 188 amino acids. N-terminal sequencing of the native protein confirmed unambiguously the cleavage site, Ala24, Val25, predicted from alignments of the sea bream PRL cDNA with that of other teleosts. The presence of only one form of PRL in sea bream was supported by identification using Northern blots of only a single transcript of 1.35 kb. Reverse transcription and polymerase chain reaction techniques coupled with Southern blot analysis resulted in the detection of PRL in the pituitary but also in the intestine, liver, ovary, and testes. PMID:10094859

  16. Bimodal Winter Haul-Out Patterns of Adult Weddell Seals (Leptonychotes weddellii) in the Southern Weddell Sea.

    PubMed

    Boehme, Lars; Baker, Amy; Fedak, Mike; Årthun, Marius; Nicholls, Keith; Robinson, Patrick; Costa, Dan; Biuw, Martin; Photopoulou, Theoni

    2016-01-01

    Hauling out is an essential component of pinniped life-history. Haul-out behaviour may be affected by biological (e.g. sex, age and condition) and physical factors (e.g. food availability and environmental conditions), and identifying these factors may help explain the spatio-temporal distribution and habitat use of pinnipeds. The aim of this study is to describe observed winter haul-out patterns of adult Weddell seals in the Weddell Sea and investigate the role of potential predictors to gain insight into the way these animals interact with the physical environment in this region. We examined the haul-out behaviour in relation to available biological (i.e., diving effort, sex) and physical information (i.e., sun angle). Thirty-three satellite telemetry tags were deployed on adult Weddell seals in the southern Weddell Sea during February 2007, 2009 and 2011, following their annual moult recording information on the behavioural mode of the animal: at surface, hauled out or diving. At the end of the austral summer Weddell seals spent, on average, more than 40% of their time hauled out on the ice. Under constant light conditions, it appears that physiological factors drive sex differences in the timing and duration of haul-out behaviour, with females spending on average more time hauled out than males during daylight hours. This time spent hauled-out declined to around 15% in both sexes by the beginning of autumn and remained at this level with a clear nocturnal haul-out pattern during the winter. The time spent diving increased during this period, indicating an increase in foraging effort during the winter months, and led to a common haul-out pattern in both sexes over winter. We found a positive relationship between haul-out duration and the percentage of time spent diving prior to a haul-out in both sexes, with the exception of female daytime haul-outs early in the year. PMID:27196097

  17. Bimodal Winter Haul-Out Patterns of Adult Weddell Seals (Leptonychotes weddellii) in the Southern Weddell Sea

    PubMed Central

    Fedak, Mike; Årthun, Marius; Nicholls, Keith; Robinson, Patrick; Costa, Dan; Biuw, Martin

    2016-01-01

    Hauling out is an essential component of pinniped life-history. Haul-out behaviour may be affected by biological (e.g. sex, age and condition) and physical factors (e.g. food availability and environmental conditions), and identifying these factors may help explain the spatio-temporal distribution and habitat use of pinnipeds. The aim of this study is to describe observed winter haul-out patterns of adult Weddell seals in the Weddell Sea and investigate the role of potential predictors to gain insight into the way these animals interact with the physical environment in this region. We examined the haul-out behaviour in relation to available biological (i.e., diving effort, sex) and physical information (i.e., sun angle). Thirty-three satellite telemetry tags were deployed on adult Weddell seals in the southern Weddell Sea during February 2007, 2009 and 2011, following their annual moult recording information on the behavioural mode of the animal: at surface, hauled out or diving. At the end of the austral summer Weddell seals spent, on average, more than 40% of their time hauled out on the ice. Under constant light conditions, it appears that physiological factors drive sex differences in the timing and duration of haul-out behaviour, with females spending on average more time hauled out than males during daylight hours. This time spent hauled-out declined to around 15% in both sexes by the beginning of autumn and remained at this level with a clear nocturnal haul-out pattern during the winter. The time spent diving increased during this period, indicating an increase in foraging effort during the winter months, and led to a common haul-out pattern in both sexes over winter. We found a positive relationship between haul-out duration and the percentage of time spent diving prior to a haul-out in both sexes, with the exception of female daytime haul-outs early in the year. PMID:27196097

  18. A new species of Coryogalops (Perciformes: Gobiidae) and the first adult record of Feia nympha from the Red Sea.

    PubMed

    Kovačić, Marcelo; Bogorodsky, Sergey V; Mal, Ahmad O

    2016-01-01

    A new species of the gobiid genus Coryogalops, C. nanus sp. nov. is described from the Red Sea. Coryogalops nanus sp. nov. is distinguished from congeners in having dorsal-fin rays VI + I,10; anal-fin rays I,9; pectoral-fin rays 12-14 (lowest count known for the genus), two upper rays with free tips; pelvic fins I,5, joined to form an emarginate disc, no pelvic frenum; predorsal area and narrow area at base of first dorsal fin naked; longitudinal scale series 26-29; transverse scale rows counted forward 6-7; transverse scale rows counted backward 7-8; circumpeduncular scale rows 11-12; seven transverse suborbital rows of sensory papillae; no tentacle above upper eye margin; anterior nostril tubular, without flap at its tip, posterior nostril pore-like; body semitranslucent, covered with small scattered orange-yellow spots and speckles, those in predorsal area contain black dots; an internal row of white spots along ventral part of body above anal-fin base and on caudal peduncle; head with small scattered orange to yellowish brown spots; first dorsal fin with two broad white bands at base of fin and distally, and with hyaline area densely dotted with melanophores in the middle of fin; preserved specimens opaque white to yellowish with sparse melanophores. An adult specimen of Feia nympha is recorded for the first time in the Red Sea and the lateral line system of this species is described. PMID:27394550

  19. Expression of spicule matrix protein gene SM30 in embryonic and adult mineralized tissues of sea urchin Hemicentrotus pulcherrimus

    NASA Technical Reports Server (NTRS)

    Kitajima, T.; Tomita, M.; Killian, C. E.; Akasaka, K.; Wilt, F. H.

    1996-01-01

    We have isolated a cDNA clone for spicule matrix protein, SM30, from sea urchin Hemicentrotus pulcherrimus and have studied the expression of this gene in comparison with that of another spicule matrix protein gene, SM50. In cultured micromeres as well as in intact embryos transcripts of SM30 were first detectable around the onset of spicule formation and rapidly increased with the growth of spicules, which accompanied accumulation of glycosylated SM30 protein(s). When micromeres were cultured in the presence of Zn2+, spicule formation and SM30 expression were suppressed, while both events resumed concurrently after the removal of Zn2+ from the culture medium. Expression of SM50, in contrast, started before the appearance of spicules and was not sensitive to Zn2+. Differences were also observed in adult tissues; SM30 mRNA was detected in spines and tube feet but not in the test, while SM50 mRNA was apparent in all of these mineralized tissues at similar levels. These results strongly suggest that the SM30 gene is regulated by a different mechanism to that of the SM50 gene and that the products of these two genes are differently involved in sea urchin biomineralization. A possible role of SM30 protein in skeleton formation is discussed.

  20. Cadmium in oysters and scallops: the BC experience.

    PubMed

    Kruzynski, George M

    2004-03-21

    Health effects of non-occupational lifetime exposure to cadmium (Cd) are of growing concern worldwide. This overview provides some context for the current situation in coastal British Columbia, Canada, which arose in 1999 from the discovery of problematic residues of Cd in farmed Pacific oysters (Crassostrea gigas). Efforts are underway to define Cd sources and the geographical and seasonal variation of these Cd residues. The recent application by the European Community of a 1 microg Cd/g (wet weight) import limit to bivalve molluscs and the current deliberation by CODEX to adopt the same value, pose significant threats to the shellfish export trade in the Pacific Northwest (British Columbia, Washington and Alaska), where natural oceanographic conditions and coastal geology contribute to levels of Cd that usually exceed the 1 ppm limit. Human health aspects of chronic Cd exposure comprise an active field of study (this Symposium) and the validity of existing Provisional Tolerable Weekly Intake is being questioned. Bioavailability of Cd from the oyster and scallop matrix is unknown and requires study. Ramifications of this uncertainty may include damage to public perception of the safety of the cultured shellfish product, loss of export market and general undermining of an industry being encouraged by both the Province of British Columbia and Federal aquaculture initiatives. There is therefore a pressing need to redefine what the "safe" limit of lifetime Cd intake is from all sources, and determine bioavailability, specifically from bivalve molluscs. Such information would facilitate the definition of scientifically defensible Cd limits by CODEX. PMID:15041066

  1. Global phylogeography of the scalloped hammerhead shark (Sphyrna lewini).

    PubMed

    Duncan, K M; Martin, A P; Bowen, B W; DE Couet, H G

    2006-07-01

    Large marine fishes typically have little population genetic structure. The exceptions are associated with sedentary behaviour, disjunct distributions, or reproductive philopatry. Scalloped hammerhead sharks (Sphyrna lewini) incorporate the contrasting traits of oceanic habitat (usually associated with high dispersal) and possible fidelity to nursery grounds (for reproductive females). To evaluate the expectations of these contrasting behaviours, we examined the global genetic structure of S. lewini based on collections (n = 271 individuals) from 20 nursery areas. A 548-bp fragment of mitochondrial DNA control region revealed 22 polymorphic sites, 24 haplotypes, and three lineages distinguished by 2.56-3.77% sequence divergence. Coalescence analyses based on a provisional molecular clock indicate an origin in the Indo-West Pacific with late Pleistocene radiations into the central Pacific (Hawaii) and eastern Pacific (Central America), as well as recent interchange between oceans via southern Africa. Population subdivisions are strong (overall Phi(ST) = 0.749, P < 0.0001 and among oceans Phi(ST) = 0.598, P < 0.0098). Genetic discontinuity within oceans (Phi(ST) = 0.519, P < 0.0001) is primarily associated with oceanic barriers (migration across oceans M approximately 0), with much less structure along continental margins (M > 10). We conclude that nursery populations linked by continuous coastline have high connectivity, but that oceanic dispersal by females is rare. Although we cannot rule out philopatry to natal nurseries, oceanic barriers appear to have a much stronger influence on the genetic architecture of this species and may indicate a mechanism for recent evolutionary radiations in the genus Sphyrna. PMID:16780437

  2. Genome-wide identification and characterization of TRAF genes in the Yesso scallop (Patinopecten yessoensis) and their distinct expression patterns in response to bacterial challenge.

    PubMed

    Wang, Jing; Wang, Ruijia; Wang, Shuyue; Zhang, Mengran; Ma, Xiaoli; Liu, Pingping; Zhang, Meiwei; Hu, Xiaoli; Zhang, Lingling; Wang, Shi; Bao, Zhenmin

    2015-11-01

    The tumor necrosis factor (TNF) receptor associated factors (TRAFs) are the major signal transducers for the TNF receptor superfamily and the interleukin-1 receptor/Toll-like receptor (IL-1R/TLR) superfamily, which regulate a variety of cellular activities and innate immune responses. TRAF genes have been extensively studied in various species, including vertebrates and invertebrates. However, as one of the key component of NF-κB pathway, TRAF genes have not been systematically characterized in marine invertebrates. In this study, we identified and characterized five TRAF genes, PyTRAF2, PyTRAF3, PyTRAF4, PyTRAF6 and PyTRAF7, in the Yesso scallop (Patinopecten yessoensis). Phylogenetic and protein structural analyses were conducted to determine their identities and evolutionary relationships. In comparison with the TRAF genes from vertebrate species, the structural features were all relatively conserved in the PyTRAF genes. To gain insights into the roles of TRAF genes during scallop innate immune responses, quantitative real-time PCR was used to investigate the expression profiles in the different stages of scallop development, in the healthy adult tissues, and in the hemocytes after bacterial infection with Micrococcus luteus and Vibrio anguillarum. Based on the qRT-PCR analysis, the expression of most of the PyTRAFs was significantly induced in the acute phases (3-6 h) after infection with Gram-positive (M. luteus) and Gram-negative (V. anguillarum) bacteria, and many more dramatic changes in PyTRAFs expression were observed after V. anguillarum challenge. Notably, the strong response in the up-regulation of PyTRAF6 post-bacterial challenge was distinct from that previously reported in scallops and crabs but was similar to that of other shellfish, Echinodermata and even teleost fish. The high level expressions of PyTRAFs in the hemocytes and the gill, and their specific expression patterns after challenges provide insights into the versatile roles and responses

  3. Age and growth of the Scalloped Hammerhead shark, Sphyrna lewini (Griffith and Smith, 1834), from the southern Brazilian coast.

    PubMed

    Kotas, J E; Mastrochirico, V; Petrere Junior, M

    2011-08-01

    Age and growth studies for the scalloped hammerhead shark, Sphyrna lewini (Griffith and Smith, 1834) caught along the southern Brazilian coast, were based on ring measurements of vertebrae sections of 115 males, 116 females and 14 unknown sexed sharks between 48 and 344 cm total length (TL). The von Bertalanffy growth models were best fit using back-calculated data. The growth parameters obtained for males, were L∞ = 266 cm; K = 0.05/year; L0 = 47 cm. For females, L∞ = 300 cm; K = 0.05/year; L0 = 51 cm. An adult female reached 217 cm TL and was 31.5 years old. On the other hand, an adult male was 29.5 years old and measured 234 cm TL. Longevity estimate for males and females was 55 years. Therefore, S. lewini is a long-lived fish. Ageing precision, based on the IAPE index, was 5.6%. Marginal Increment analysis based on MIR index from hammerheads smaller than 105 cm, compared with the percentual of opaque and hyaline bands found per month ageing whole vertebrae, showed an annual ring formation, i.e., in winter. PMID:21881801

  4. Age, growth and maturity of the pelagic thresher Alopias pelagicus and the scalloped hammerhead Sphyrna lewini.

    PubMed

    Drew, M; White, W T; Dharmadi; Harry, A V; Huveneers, C

    2015-01-01

    Indonesia has the greatest reported chondrichthyan catches worldwide, with c.110,000 t caught annually. The pelagic thresher (Alopias pelagicus) and scalloped hammerhead (Sphryna lewini) together comprise about 25% of the total catches of sharks landed in Indonesia. Age and growth parameters were estimated for A. pelagicus and S. lewini from growth-band counts of thin-cut vertebral sections. Alopias pelagicus (n = 158) and S. lewini (n = 157) vertebrae were collected from three Indonesian fish markets over a 5 year period. A multi-model analysis was used to estimate growth parameters for both species. The models of best fit for males and females for A. pelagicus was the three-parameter logistic (L∞ = 3169 mm LT , k = 0·2) and the two-parameter von Bertalanffy models (L∞ = 3281 mm LT , k = 0·12). Age at maturity was calculated to be 10·4 and 13·2 years for males and females, respectively, and these are the oldest estimated for this species. The samples of S. lewini were heavily biased towards females, and the model of best fit for males and females was the three-parameter Gompertz (L∞ = 2598 mm LT , k = 0·15) and the two-parameter Gompertz (L∞ = 2896 mm LT , k= 0·16). Age at maturity was calculated to be 8·9 and 13·2 years for males and females, respectively. Although numerous age and growth studies have previously been undertaken on S. lewini, few studies have been able to obtain adequate samples from all components of the population because adult females, adult males and juveniles often reside in different areas. For the first time, sex bias in this study was towards sexually mature females, which are commonly lacking in previous biological studies on S. lewini. Additionally, some of the oldest aged specimens and highest age at maturity for both species were observed in this study. Both species exhibit slow rates of growth and late age at maturity, highlighting the need for a re-assessment of the relative resilience of these two

  5. The Scallop's Eye--A Concave Mirror in the Context of Biology

    ERIC Educational Resources Information Center

    Colicchia, Giuseppe; Waltner, Christine; Hopf, Martin; Wiesner, Hartmut

    2009-01-01

    Teaching physics in the context of medicine or biology is a way to generate students' interest in physics. A more uncommon type of eye, the scallop's eye (an eye with a spherical concave mirror, which is similar to a Newtonian or Schmidt telescope) and the image-forming mechanism in this eye are described. Also, a simple eye model, which can…

  6. A half century of scalloping in the work habits of the United States Congress.

    PubMed Central

    Critchfield, Thomas S; Haley, Rebecca; Sabo, Benjamin; Colbert, Jorie; Macropoulis, Georgette

    2003-01-01

    It has been suggested that the work environment of the United States Congress bears similarity to a fixed-interval reinforcement schedule. Consistent with this notion, Weisberg and Waldrop (1972) described a positively accelerating pattern in annual congressional bill production (selected years from 1947 to 1968) that is reminiscent of the scalloped response pattern often attributed to fixed-interval schedules, but their analysis is now dated and does not bear on the functional relations that might yield scalloping. The present study described annual congressional bill production over a period of 52 years and empirically evaluated predictions derived from four hypotheses about the mechanisms that underlie scalloping. Scalloping occurred reliably in every year. The data supported several predictions about congressional productivity based on fixed-interval schedule performance, but did not consistently support any of three alternative accounts. These findings argue for the external validity of schedule-controlled operant behavior as measured in the laboratory. The present analysis also illustrates a largely overlooked role for applied behavior analysis: that of shedding light on the functional properties of behavior in uncontrolled settings of considerable interest to the public. PMID:14768667

  7. 50 CFR 648.64 - Yellowtail flounder sub-ACLs and AMs for the scallop fishery.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Yellowtail flounder sub-ACLs and AMs for the scallop fishery. 648.64 Section 648.64 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE...

  8. Effects of environmental oxygen deficiency on embryos and larvae of bay scallop, Argopecten irradians irradians

    NASA Astrophysics Data System (ADS)

    Chun-de, Wang; Fu-Sui, Zhang

    1995-12-01

    The experimental results showed that: 1) The embryonic development of bay scallop is inhibited at a dissolved oxygen range of 1.38-3.64×10-3 at 23°C, and completely blocked below the lower limit. 2) The tolerance of larvae to anoxia increased with larval sizes and was related to their oxygen debt. 3) The scallop larvae exhibited specific behavioral responses to oxygen deficiency, which finally led to velum disintegration and larval death. The possible relationship between environmental oxygen deficiency and the disease of disintegration of the larval velum is also discussed. In this study, considerable oxygen debt was found in bay scallop larvae, which was greater in small animals. Based on the works of previous authors, a new concept is proposed for the estimation of oxygen debt, namely, the compensatory rate of oxygen debt (CROD). This can be used in intra—or interspecific comparison of oxygen debt. The results can be helpful in the management of water quality and for the prevention of larval diseases encountered in scallop culture.

  9. Co-evolution of polygonal and scalloped terrains, southwestern Utopia Planitia, Mars

    NASA Astrophysics Data System (ADS)

    Haltigin, T. W.; Pollard, W. H.; Dutilleul, P.; Osinski, G. R.; Koponen, L.

    2014-02-01

    Thermal contraction crack polygons and scalloped depressions, two of the most common landforms found in Utopia Planitia, Mars, have previously been linked to the presence of ice-rich deposits in the subsurface. Although the formation and evolution of these features individually are relatively well understood, little to no effort has been directed towards elucidating possible interactions that occur between them during their development. Thus, the overarching goal of this research was to investigate if there is an evolutionary link between polygonal and scalloped terrains by correlating metrics representing polygon and scallop maturity. A variety of statistical analyses were performed using HiRISE and MOLA datasets to quantify interactions between four sets of polygonal and scalloped terrains. Our results demonstrate the existence of a negative relationship between polygonal subdivision and surface elevation, indicating that polygon networks become more ‘evolved’ as the surface subsides. These results suggest that the permafrost landscape in Utopia Planitia may once have been extremely ice-rich, and that multiple geomorphic processes may be responsible for its evolution. Ultimately, this work demonstrates that landscape reconstruction is more complete when a system approach is followed, quantifying interactions between landforms as opposed to examining an individual landform in isolation.

  10. First evidence of marine diesel effects on biomarker responses in the Icelandic scallops, Chlamys islandica.

    PubMed

    Geraudie, Perrine; Bakkemo, Renée; Milinkovitch, Thomas; Thomas-Guyon, Helene

    2016-08-01

    The decrease of ice cover in polar areas is expected to lead to an increase in ship traffic. In this context, the risk associated with exposure of the aquatic environment to oil-related chemicals from spills and/or accidental fuel discharges from ships will increase in the near future, potentially causing negative impacts on sensitive Arctic species. This study investigated for the first time the biomarker responses of the Icelandic scallops (Chlamys islandica) to marine diesel exposure. Antioxidant response, neurotoxic effect, gonad maturation, and lipid content were assessed in male and female scallops, Chlamys islandica after a 7-day exposure to marine diesel. At the end of exposure, results showed an inhibition of acetylcholinesterase activity in Icelandic scallops exposed to high concentration of diesel. At the end of exposure, results showed an increase in naphthalene residues in hemolymph, together with an inhibition of AChE activity in Icelandic scallops exposed to high concentration of diesel. In addition, alteration of the escape capacity was observed suggesting effects on behavior responses. Overall, this study contributes to the better knowledge of physiological effects of marine diesel in Arctic marine organisms. PMID:27169408

  11. 50 CFR 648.62 - Northern Gulf of Maine (NGOM) scallop management area.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Northern Gulf of Maine (NGOM) scallop management area. 648.62 Section 648.62 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE NORTHEASTERN UNITED STATES Management Measures for the...

  12. Rediscovery of the Yesso scallop pathogen Perkinsus qugwadi in Canada, and development of PCR tests.

    PubMed

    Itoh, Naoki; Meyer, Gary R; Tabata, Amy; Lowe, Geoff; Abbott, Cathryn L; Johnson, Stewart C

    2013-04-29

    Perkinsus qugwadi, a pathogenic protozoan parasite of Yesso scallops Patinopecten yessoensis, is found only in cultured populations in British Columbia, Canada. This pathogen was first identified in 1988 and caused significant mortalities at some locations during the early 1990s. Prevalence of infection decreased dramatically following 1995, and the disease was last reported in 1997, leading to speculation that the Yesso scallop stocks in Canada had developed resistance to the disease, or that P. qugwadi had disappeared. However, the present study revealed that infection with P. qugwadi and associated mortality is still occurring in scallops from at least one location in British Columbia. One of the PCR tests developed for P. qugwadi detected the parasite in a 105-fold dilution of DNA extracted from a heavily infected sample and detected 52% more positive scallops than histology; however, the assay also cross-reacted with P. honshuensis and P. olseni. The other PCR test was less sensitive and detected 34% more positives, but did not react to any of the other Perkinsus species tested, suggesting that these PCR tests are powerful tools for screening for the presence of P. qugwadi. Phylogenetic analysis of 1796 bp of SSU rRNA gene sequence clearly indicated that P. qugwadi is positioned basally to other Perkinsus species. PMID:23670082

  13. 76 FR 23794 - Stock Status Determination for Atlantic Highly Migratory Scalloped Hammerhead Shark

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-28

    ...This action serves as a notice that NMFS, on behalf of the Secretary of Commerce (Secretary), has determined that overfishing is occurring on an Atlantic highly migratory species (HMS) scalloped hammerhead shark, and the stock is overfished. NMFS notifies the public whenever it determines that: overfishing is occurring, a stock is overfished, or a stock is approaching an overfished...

  14. Elimination of super(14)C-bisazir residues in adult sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Allen, J.L.; Dawson, V.K.

    1987-01-01

    Bisazir (P.P-bis(1-aziridinyl)-N-methylphosphinothioic amide), a chemosterilant, was administered to sea lampreys (Petromyzon marinus ) by intraperitoneal injection of 100 mg/kg or by immersion for 2 h in a 100- mg/L aqueous solution of the chemical. Whole body analysis of the injected lampreys showed that total residue concentrations decreased to 4.65 in males and 10.07 in females during the first day after injection, and to 1.46 in males and 3.74 in females after 10 days of withdrawal. Lampreys exposed by bath immersion contained residues of about 25 mu g/g of tissue immediately after exposure. The concentration ( mu g/g) decreased to 1.02 in males and 2.11 in females after 1 day of withdrawal and to 0.51 in males and 0.85 in females after 10 days.

  15. Determination of polyaromatic hydrocarbons in scallops (Pecten maximus) by UV fluorescence and HPLC combined with UV and fluorescence detectors

    SciTech Connect

    Friocourt, M.P.; Bodennec, G.; Berthou, F.

    1985-02-01

    During the last few years, the northern coasts of Brittany (France) were heavily polluted with several oil spills. This area of considerable economic importance for its oyster and scallop production is heavily dependent on the quality of its coastline and inshore waters. After the Amoco Cadiz oil spill, studies have been conducted on oysters from defined areas to determine the fate and effects of the hydrocarbons. No work was done on scallop samples. The purpose of this paper is to provide information on the level of hydrocarbon pollution in areas concerned with scallop breeding. It is an attempt to use these organisms as biomonitors.

  16. Changes in global DNA methylation intensity and DNMT1 transcription during the aging process of scallop Chlamys farreri

    NASA Astrophysics Data System (ADS)

    Lian, Shanshan; He, Yan; Li, Xue; Zhao, Bosong; Hou, Rui; Hu, Xiaoli; Zhang, Lingling; Bao, Zhenmin

    2015-08-01

    DNA methylation is an important epigenetic regulatory mechanism that influences genomic stability, gene activation, X-chromosome inactivation and other factors. A change in DNA methylation is usually associated with aging and cellular senescence. DNA methyltransferase 1 (DNMT1) is the most abundant DNA methyltransferase, and it plays an important role in maintaining the established methylation pattern during DNA replication in vertebrates. Although the effect of aging on DNA methylation has been well studied in vertebrates, little research has been conducted in invertebrates, especially in marine bivalves. In this study, we examined global DNA methylation levels in four groups of adult Zhikong scallop Chlamys farreri at different ages. The results showed that both the age and tissue type had a strong effect on the DNA methylation. In addition, a significant decrease in DNA methylation with aging (1-4 years) can be detected in mantle, kidney and hepatopancreas. We further measured the change in DNMT1 transcript abundance using quantitative reverse transcription PCR (qRT-PCR), which revealed that DNMT1 transcription significantly decreased with aging in mantle and hepatopancreas and strongly correlated with DNA methylation ( R = 0.72). Our data provided greater insight into the aging-related decline of DNA methylation, which could aid in gaining a better understanding of the relationship between DNA methylation and the aging process in bivalve mollusks.

  17. Scalloped terrains in the Peneus and Amphitrites Paterae region of Mars as observed by HiRISE

    NASA Astrophysics Data System (ADS)

    Lefort, A.; Russell, P. S.; Thomas, N.

    2010-01-01

    The Peneus and Amphitrites Paterae region of Mars displays large areas of smooth, geologically young terrains overlying a rougher and older topography. These terrains may be remnants of the mid-latitude mantle deposit, which is thought to be composed of ice-rich material originating from airfall deposition during a high-obliquity period less than 5 Ma ago. Within these terrains, there are several types of potentially periglacial features. In particular, there are networks of polygonal cracks and scalloped-shaped depressions, which are similar to features found in Utopia Planitia in the northern hemisphere. This area also displays knobby terrain similar to the so-called "basketball terrains" of the mid and high martian latitudes. We use recent high resolution images from the High Resolution Imaging Science Experiment (HiRISE) along with data from previous Mars missions to study the small-scale morphology of the scalloped terrains, and associated polygon network and knobby terrains. We compare these with the features observed in Utopia Planitia and attempt to determine their formation process. While the two sites share many general features, scallops in Peneus/Amphitrites Paterae lack the diverse polygon network (i.e. there is little variation in the polygon sizes and shapes) and large curvilinear ridges observed in Utopia Planitia. This points to a more homogeneous ice content within the substrate in the Peneus/Amphitrites Paterae region and implies that scallop formation is independent of polygon formation. This work shows that, as in Utopia Planitia, sublimation of interstitial ice is a likely process explaining the formation of the scalloped depressions in the region of Peneus/Amphitrites Paterae. Therefore, we provide a simplified scallop formation model based on sublimation of interstitial ice as proposed for Utopia Planitia. We also show that the differences in scallop morphologies between the two regions may be explained by differences in near-surface ice

  18. Development of method to remove weld scallop and ceramic backing material of wedge type and its application

    NASA Astrophysics Data System (ADS)

    Kang, Sung-Koo; Yang, Jong-Soo; Kim, Ho-Kyung

    2015-06-01

    The weld scallop has been used for joining T-bars. There are a lot of weld scallops in shipbuilding. It is difficult to perform scallop welding due to the inconvenient welding position. This results in many problems such as porosity, slag inclusion, etc. In this study, a new method is devised to remove weld scallops by incorporating a Ceramic Backing Material (CBM). The weld scallop is removed by an elongation of the v groove. In order to insert a CBM into the groove without a weld scallop, a wedge-shaped CBM is developed. The top side of the developed CBM is similar to the shape of a general back bead. The bottom surface has a saw-toothed shape for cutting at a suitable length. This can be attached to the root side of a face plate using adhesive tape, just like a general CBM. Welding experiments in normal and abnormal conditions are carried out and the possibility of burn-through is examined. This CBM's applicability to shipbuilding is verified.

  19. Assimilation, Accumulation, and Metabolism of Dinophysistoxins (DTXs) and Pectenotoxins (PTXs) in the Several Tissues of Japanese Scallop Patinopecten yessoensis

    PubMed Central

    Matsushima, Ryoji; Uchida, Hajime; Nagai, Satoshi; Watanabe, Ryuichi; Kamio, Michiya; Nagai, Hiroshi; Kaneniwa, Masaki; Suzuki, Toshiyuki

    2015-01-01

    Japanese scallops, Patinopecten yessoensis, were fed with the toxic dinoflagellate Dinophysis fortii to elucidate the relative magnitude of assimilation, accumulation, and metabolism of diarrhetic shellfish toxins (DSTs) and pectenotoxins (PTXs). Three individual scallops were separately exposed to cultured D. fortii for four days. The average cell number of D. fortii assimilated by each individual scallop was 7.7 × 105. Dinophysistoxin-1 (DTX1), pectenotoxin-2 (PTX2) and their metabolites were analyzed by liquid chromatography tandem mass spectrometry (LC/MS/MS) and the toxin content in individual tissues (digestive gland, adductor muscle, gill, gonad, mantle, and the others), feces and the seawater medium were quantified. Toxins were almost exclusively accumulated in the digestive gland with only low levels being detected in the gills, mantles, gonads, and adductor muscles. DTX1 and PTX2 were the dominant toxins in the D. fortii cells fed to the scallops, whereas the dominant toxins detected in the digestive gland of scallops were PTX6 and esterified acyl-O-DTX1 (DTX3). In other tissues PTX2 was the dominant toxin observed. The ratio of accumulated to assimilated toxins was 21%–39% and 7%–23% for PTXs and DTXs respectively. Approximately 54%–75% of PTX2 and 52%–70% of DTX1 assimilated by the scallops was directly excreted into the seawater mainly without metabolic transformation. PMID:26633503

  20. Formation and Evolution of Scalloped Depressions on Malea Planum and the southern rim of the Hellas Basin, Mars

    NASA Astrophysics Data System (ADS)

    Zanetti, M.; Hiesinger, H.; Reiss, D.; Neukum, G.

    2008-09-01

    Introduction: Scalloped depressions are an erosional surface morphology characterized as a type of dissected mantle terrain by Milliken and Mustard [1]. They are identified by their asymmetrical north-south profile which shows a steep pole-facing scarp, a flat floor, and a gentle equator-facing slope which grades into the surrounding terrain [1]. They are found in latitudedependent, ice-rich surface mantles in both the northern and southern hemispheres [1]. The mantle material is presumably composed of atmospherically derived dust and water ice, and is thought to be related to obliquity-driven ice activity as recently as 2.1-0.4 Myr ago [3]. Previous researchers, [e.g. 1,2,4-7] have attributed the formation of scallops to the sublimation of interstitial ice. Morgenstern et al. [6] suggested that the asymmetric profile of scallops can be explained by enhanced solar insolation on the equator-facing slope which leads to enhanced sublimation of interstial ice and thereby increases the area of the depression. By this process they can also grow and coalesce to form large degraded areas [6]. Building on our previous work [7], we investigate this hypothesis using HiRISE and THEMIS-IR images. We also propose a hypothesis for the nucleation and evolution of scallops. Previous Work: Our previous work surveyed the southern hemisphere using HRSC images for the presence of scalloped terrain, and revealed that almost all scalloped terrains are in the Malea Planum region near the southern wall of the Hellas basin [7]. We mapped the distribution of scalloped terrain between 50° and 70° E and 50° and 70° S. The results of the map showed that the scalloped terrains contour the southern wall of the Hellas basin between the elevations of 1000 m and -2000 m, and that the icerich mantle is thickest in this region [7]. Data and Methods: High resolution HiRISE images of the scalloped terrain of Malea Planum were used to investigate small scale features. Daytime infrared images from

  1. Mapping toll-like receptor signaling pathway genes of Zhikong scallop ( Chlamys farreri) with FISH

    NASA Astrophysics Data System (ADS)

    Zhao, Bosong; Zhao, Liang; Liao, Huan; Cheng, Jie; Lian, Shanshan; Li, Xuan; Huang, Xiaoting; Bao, Zhenmin

    2015-12-01

    Toll-like receptor (TLR) signaling pathway plays a pivotal role in the innate immune system. Studies on TLR signaling pathway genes in Zhikong scallop ( Chlamys farreri) have mainly focused on sequence analysis and expression profiling, no research has been carried out on their localization. The chromosomal position of TLR signaling pathway genes can be valuable for assemblying scallop genome and analysizing gene regulatory networks. In the present study, five key TLR signaling pathway genes ( CfTLR, CfMyd88, CfTRAF6, CfNFκB, and CfIκB) containing bacterial artificial chromosomes (BACs) were isolated and physically mapped through fluorescence in situ hybridization on five non-homologous chromosome pairs, showing a similar distribution to another five model species. The isolation and mapping of these key immune genes of C. farreri will aid to the research on innate immunity, assignment of interested genes to chromosomes, and integration of physical, linkage and cytogenetic maps of this species.

  2. In the darkness of the polar night, scallops keep on a steady rhythm

    PubMed Central

    Tran, Damien; Sow, Mohamedou; Camus, Lionel; Ciret, Pierre; Berge, Jorgen; Massabuau, Jean-Charles

    2016-01-01

    Although the prevailing paradigm has held that the polar night is a period of biological quiescence, recent studies have detected noticeable activity levels in marine organisms. In this study, we investigated the circadian rhythm of the scallop Chlamys islandica by continuously recording the animal’s behaviour over 3 years in the Arctic (Svalbard). Our results showed that a circadian rhythm persists throughout the polar night and lasts for at least 4 months. Based on observations across three polar nights, we showed that the robustness and synchronicity of the rhythm depends on the angle of the sun below the horizon. The weakest rhythm occurred at the onset of the polar night during the nautical twilight. Surprisingly, the circadian behaviour began to recover during the darkest part of the polar night. Because active rhythms optimize the fitness of an organism, our study brings out that the scallops C. islandica remain active even during the polar night. PMID:27577847

  3. Construction of bacterial artificial chromosome libraries for Zhikong Scallop Chlamys farreri

    NASA Astrophysics Data System (ADS)

    Zhang, Yang; Zhang, Xiaojun; Scheuring, Chantel F.; Zhang, Hongbin; Li, Fuhua; Xiang, Jianhai

    2008-05-01

    Two Large-insert genomic bacterial artificial chromosome (BAC) libraries of Zhikong scallop Chlamys farreri were constructed to promote our genetic and genomic research. High-quality megabase-sized DNA was isolated from the adductor muscle of the scallop and partially digested by BamH I and Mbo I, respectively. The BamH I library consisted of 53 760 clones while the Mbo I library consisted of 7 680clones. Approximately 96 % of the clones in BamH I library contained nuclear DNA inserts in average size of 100 kb, providing a coverage of 5.3 haploid genome equivalents. Similarly, the Mbo I library with an average insert of 145 kb and no insert-empty clones, thus providing a genome coverage of 1.1 haploid genome equivalents.

  4. In the darkness of the polar night, scallops keep on a steady rhythm.

    PubMed

    Tran, Damien; Sow, Mohamedou; Camus, Lionel; Ciret, Pierre; Berge, Jorgen; Massabuau, Jean-Charles

    2016-01-01

    Although the prevailing paradigm has held that the polar night is a period of biological quiescence, recent studies have detected noticeable activity levels in marine organisms. In this study, we investigated the circadian rhythm of the scallop Chlamys islandica by continuously recording the animal's behaviour over 3 years in the Arctic (Svalbard). Our results showed that a circadian rhythm persists throughout the polar night and lasts for at least 4 months. Based on observations across three polar nights, we showed that the robustness and synchronicity of the rhythm depends on the angle of the sun below the horizon. The weakest rhythm occurred at the onset of the polar night during the nautical twilight. Surprisingly, the circadian behaviour began to recover during the darkest part of the polar night. Because active rhythms optimize the fitness of an organism, our study brings out that the scallops C. islandica remain active even during the polar night. PMID:27577847

  5. Scalloped margin domes: What are the processes responsible and how do they operate?

    NASA Technical Reports Server (NTRS)

    Bulmer, M. H.; Guest, J. E.; Michaels, G.; Saunders, S.

    1993-01-01

    Studies of scalloped margin domes (SMD) indicate the scallops are the result of slope failure. SMD's have similar but smaller average diameters (26.5 km) to unmodified domes (29.8 km), and the majority plot at altitudes ranging from 0.5-4.7 km, relative to the mean planetary diameter. A range of morphological types exist from those least modified to those that show heavy modification. Of the 200 SMD's examined, 33 have clearly discernible debris aprons. Examination and comparison of debris aprons with mass movement features on the Moon, Mars, and in sub-aerial and submarine environments on Earth using H/L against area (km(sup 2)), suggests there are three main types of failure; debris avalanche, slumps, and debris flow. The five examples representing the morphological range within the SMD's, show the different modified forms and the different types of slope failures that have occurred.

  6. Cloning and sequencing of a cDNA for Akazara scallop troponin T.

    PubMed

    Inoue, A; Ojima, T; Nishita, K

    1996-10-01

    A cDNA clone encoding troponin T of Akazara scallop (Chlamys nipponensis akazara) striated adductor muscle has been isolated and sequenced. The complete sequence deduced consists of 314 amino acid residues with a molecular weight of 37,206. Akazara scallop troponin T contains 55 amino acid residues more and 82 residues fewer than rabbit skeletal muscle troponin T and Drosophila melanogaster troponin T, respectively, showing almost the lowest sequence homology with rabbit troponin T (26%) but the highest homology with Drosophila troponin T (33%). Further, high sequence homology was seen in the functional regions: residues 33-120 and 174-227, corresponding respectively to residues 71-158 and 197-250 of rabbit troponin T (tropomyosin-binding regions); and residues 200-204, corresponding to 223 227 of rabbit troponin T (troponin I-binding region). In residues 1-70 (tropomyosin-binding region), however, only six residues are identical with rabbit troponin T. PMID:8947849

  7. Expression of hematopoietic transcription factors Runt, CBFβ and GATA during ontogenesis of scallop Chlamys farreri.

    PubMed

    Yue, Feng; Wang, Lingling; Wang, Hao; Song, Linsheng

    2016-08-01

    Transcription factors Runx1, CBFβ and GATA1/2/3 play essential roles in regulating hematopoietic development during embryogenesis of vertebrate. In previous study, the orthologous genes of Runt, CBFβ and GATA1/2/3 have been identified from scallop Chlamys farreri and proved to have conserved function in regulating hemocyte production. Here, these three transcription factors were selected as hematopoietic markers to explore potential developmental events of hematopoiesis during ontogenesis of scallop. The transcripts of CfRunt, CfCBFβ and CfGATA were detected abundantly after 32-cell embryo, trochophore and morula stage, and reached to a peak level in 32-cell embryos and D-shaped veligers, pediveligers or gastrula respectively. Further whole-mount immunofluorescence assay showed that the immunoreactivity of CfRunt was firstly observed at 32-cell stage and then its distribution was specialized gradually to the mesoderm during gastrulation. By trochophore, the expression of CfRunt, CfCBFβ and CfGATA proteins occurred coincidently in two specific symmetry cell mass located bilaterally on prototroch, and then disappeared rapidly in D-shaped or umbonal vliger, respectively. However, remarkable expressions of the three transcription factors were observed consistently in a new sinus structure appeared at the dorsal anterior side of D-shaped and umbonal veliger. After bacterial challenge, the mRNA expression levels of the three transcription factors were up-regulated or down-regulated significantly in trochophore, D-shaped veliger and pediveliger, indicating the available hematopoietic regulation in scallop larvae. The results revealed that scallop might experience two waves of hematopoiesis during early development, which occurred in the bilateral symmetry cell mass of trochophore and the sinus structure of veliger. PMID:27012994

  8. Metallothionein-like proteins induced by cadmium stress in the scallop Mizuhopecten yessoensis

    NASA Astrophysics Data System (ADS)

    Zhukovskaya, Avianna F.; Belcheva, Nina N.; Slobodskova, Valentina S.; Chelomin, Viktor P.

    2012-09-01

    Organisms have evolved a cellular response called stress protein response that increases their tolerance in adverse environmental conditions. Well known stress proteins that bind essential and toxic metals are metallothionein (MT). The scallop Mizuhopecten yessoensis is the most interesting organism because it is able to accumulate toxic cadmium in its digestive gland. However, in the tissue of the digestive gland of Mizuhopecten yessoensis MT (metallothioneins) have not been found. Eastern scallops, Mizuhopecten yessoensis, were collected from two locations — one clean and one polluted site. The concentrations of cadmium (Cd), copper (Cu) and zinc (Zn) were measured in the digestive gland. There was a significant increase in Cd concentrations in this studied tissue. We found that in the presence of cadmium Mizuhopecten yessoensis can induce high molecular proteins. The results of experiments have shown that Cd-binding ligands have a number of properties similar to MT: acetone and temperature stability; the ability to bind some metals, including Cd, Cu and Zn. Protein chromatography (FPLC, Superosa 12) from the digestive gland of scallop M. yessoensis has shown that cadmium is associated with high molecular weight Cd-binding proteins (72 kDa and 43 kDa). The major cadmium-binding protein 72 kDa is glycoprotein. In experiments we have demonstrated that Cd-binding proteins can be induced when there is cadmium exposure. The results of this study strongly suggest that the far eastern scallop Mizuhopecten yessoensis has a unique and well-developed system for the detoxification of heavy metals and it allows for biochemical systems to be maintained in a relatively stable manner in the presence of heavy metals.

  9. Thermokarst in Siberian ice-rich permafrost: Comparison to asymmetric scalloped depressions on Mars

    NASA Astrophysics Data System (ADS)

    Ulrich, M.; Morgenstern, A.; Günther, F.; Reiss, D.; Bauch, K. E.; Hauber, E.; Rössler, S.; Schirrmeister, L.

    2010-10-01

    On Earth, the thawing of permafrost deposits with high-ground ice content results in massive surface subsidence and the formation of characteristic large thermokarst depressions. Slope asymmetries within thermokarst depressions suggest lateral growth, which occurs due to thermoerosion and gravimetric mass wasting along these slopes. It has been proposed that rimless, asymmetrically shaped depressions (called scalloped depressions) on Mars were formed by insolation-driven ground ice sublimation. We investigated a large thermokarst depression in ice complex deposits in the Siberian Arctic as a terrestrial analogue for scalloped depressions in Martian volatile-rich mantle deposits. Our results from field studies, insolation modeling, and geomorphometric analyses suggest lateral thermokarst development in a northern direction. This conclusion is obvious due to steeper slope angles of the south facing slopes. Insolation and surface temperatures are crucial factors directly influencing thermokarst slope stability and steepness. Comparative analyses of Martian scalloped depressions in Utopia Planitia were conducted using high-resolution (High-Resolution Imaging Science Experiment, Context Camera) and thermal infrared (Thermal Emission Imaging System) satellite data. By direct analogy, we propose that the lateral scalloped depression development on Mars was primarily forced on the steep pole-facing slopes in the equator-ward direction. Insolation modeling confirms that this must have happened in the last 10 Ma during an orbital configuration of higher obliquity than today. Development would have been maximized if the orbit was both highly oblique and highly eccentric, and/or the Martian summer coincided with perihelion. Relatively short events of increasing sublimation or even thawing of ground ice led to fast slumping processes on the steep pole-facing slopes.

  10. 75 FR 36559 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Framework Adjustment 21

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-28

    ... Lightship Access Area (NLAA). For FY 2010, this equates to 47 mt; 103,617 lb (April 9, 2010; 75 FR 18356... described in the status review and the proposed rule published on March 16, 2010 (75 FR 12597)), then... was initially established through Joint Framework 16/39 (69 FR 63460; November 2, 2004),...

  11. 76 FR 43773 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Framework Adjustment 22

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-21

    ... Federal Register on April 29, 2011 (76 FR 23940), with a 30-day public comment period that ended May 31... Register on June 1, 2011 (76 FR 31491). Although Framework 22 closes NLS, because Framework 22 was not... Multispecies FMP (76 FR 23042; April 25, 2011) set the total YTF ACLs outlined in Table 3 for FYs 2011 and...

  12. 50 CFR 648.60 - Sea scallop access area program requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...)(8)(i). Editorial Note: For Federal Register citations affecting § 648.60, see the List of CFR... Areas—(1) Access Areas available for harvest of research set-aside (RSA). Unless otherwise specified, RSA may be harvested in any access area that is open in a given fishing year, as specified through...

  13. 76 FR 31491 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Closure of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-01

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  14. 77 FR 20728 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Framework Adjustment 23

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-06

    ... January 3, 2012 (77 FR 52), with a 15-day public comment period that ended January 18, 2012. Three... exceeded its sub-ACL by 150 percent). The proposed rule for Framework 47 (77 FR 18179) published in the... regulations to clarify the terminology intended by Amendment 15 to the FMP (76 FR 43746, July 21, 2011),...

  15. 77 FR 64915 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Emergency Rule...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-24

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  16. A cross-sectional study of differences in 6-min walk distance in healthy adults residing at high altitude versus sea level

    PubMed Central

    2014-01-01

    Background We sought to determine if adult residents living at high altitude have developed sufficient adaptation to a hypoxic environment to match the functional capacity of a similar population at sea level. To test this hypothesis, we compared the 6-min walk test distance (6MWD) in 334 residents living at sea level vs. at high altitude. Methods We enrolled 168 healthy adults aged ≥35 years residing at sea level in Lima and 166 individuals residing at 3,825 m above sea level in Puno, Peru. Participants completed a 6-min walk test, answered a sociodemographics and clinical questionnaire, underwent spirometry, and a blood test. Results Average age was 54.0 vs. 53.8 years, 48% vs. 43% were male, average height was 155 vs. 158 cm, average blood oxygen saturation was 98% vs. 90%, and average resting heart rate was 67 vs. 72 beats/min in Lima vs. Puno. In multivariable regression, participants in Puno walked 47.6 m less (95% CI -81.7 to -13.6 m; p < 0.01) than those in Lima. Other variables besides age and height that were associated with 6MWD include change in heart rate (4.0 m per beats/min increase above resting heart rate; p < 0.001) and percent body fat (-1.4 m per % increase; p = 0.02). Conclusions The 6-min walk test predicted a lowered functional capacity among Andean high altitude vs. sea level natives at their altitude of residence, which could be explained by an incomplete adaptation or a protective mechanism favoring neuro- and cardioprotection over psychomotor activity. PMID:24484777

  17. Scallop larvae hatcheries as source of bacteria carrying genes encoding for non-enzymatic phenicol resistance.

    PubMed

    Miranda, Claudio D; Rojas, Rodrigo; Geisse, Julieta; Romero, Jaime; González-Rocha, Gerardo

    2015-06-15

    The main aim of the study was to evaluate the role of scallop hatcheries as source of the floR and cmlA genes. A number of 133 and 121 florfenicol-resistant strains were isolated from scallop larval cultures prior to their transfer to seawater and from effluent samples from 2 commercial hatcheries and identified by 16S rRNA gene sequence analysis, observing a predominance of the Pseudomonas, Pseudoalteromonas and Halomonas genera and exhibiting an important incidence of co-resistance to streptomycin, oxytetracycline and co-trimoxazole. A high percentage of strains from both hatcheries carried the floR gene (68.4% and 89.3% of strains), whereas a lower carriage of the cmlA gene was detected (27.1% and 54.5% of strains). The high prevalence of floR-carrying bacteria in reared scallop larvae and hatchery effluents contributes to enrich the marine resistome in marine environments, prompting the need of a continuous surveillance of these genes in the mariculture environments. PMID:25956439

  18. Trends in the sand: Directional evolution in the shell shape of recessing scallops (Bivalvia: Pectinidae).

    PubMed

    Sherratt, Emma; Alejandrino, Alvin; Kraemer, Andrew C; Serb, Jeanne M; Adams, Dean C

    2016-09-01

    Directional evolution is one of the most compelling evolutionary patterns observed in macroevolution. Yet, despite its importance, detecting such trends in multivariate data remains a challenge. In this study, we evaluate multivariate evolution of shell shape in 93 bivalved scallop species, combining geometric morphometrics and phylogenetic comparative methods. Phylomorphospace visualization described the history of morphological diversification in the group; revealing that taxa with a recessing life habit were the most distinctive in shell shape, and appeared to display a directional trend. To evaluate this hypothesis empirically, we extended existing methods by characterizing the mean directional evolution in phylomorphospace for recessing scallops. We then compared this pattern to what was expected under several alternative evolutionary scenarios using phylogenetic simulations. The observed pattern did not fall within the distribution obtained under multivariate Brownian motion, enabling us to reject this evolutionary scenario. By contrast, the observed pattern was more similar to, and fell within, the distribution obtained from simulations using Brownian motion combined with a directional trend. Thus, the observed data are consistent with a pattern of directional evolution for this lineage of recessing scallops. We discuss this putative directional evolutionary trend in terms of its potential adaptive role in exploiting novel habitats. PMID:27375214

  19. Identification of Cytochrome P450 ( CYP) genes in Zhikong scallop ( Chlamys farreri)

    NASA Astrophysics Data System (ADS)

    Guo, Huihui; Bao, Zhenmin; Du, Huixia; Zhang, Lingling; Wang, Shi; Sun, Luyang; Mou, Xiaoyu; Hu, Xiaoli

    2013-03-01

    Cytochrome P450 ( CYP) superfamily is one of the membership largest and function most diverse protein superfamily recogniozed among living beings. Members of this superfamily were further assigned to different families and subfamilies based on their amino acid similarities. According to their phylogenetic relationships, the CYP genes which likely diverged from common ancestor gene and may share common functions were grouped into one clan. Widely distributing scallops are a group of the most conspicuous bivalve; however the studies on their CYP is acarce. In this study, we searched the genome and expressed sequence tags of Zhikong scallop ( Chlamys farreri) for CYP genes. In total, 88 non-redundant CYP were identified, which were homed in 13 CYPs gene families. Phylogenetic analysis divided these genes into 4 CYP clans. As in deuterostomes, Clan 2 was the largest, which contained 33 genes belonging to CYP1, CYP2, CYP17 and CYP356 families. Clan 3 contgained 19 genes belonging to CYP3, CYP5 and CYP30 families. Clan 4 contained 23 genes, all belonging to CYP4 family. The mitochondrial CYP clan contained 9 genes belonging to CYP10 and CYP24 families. In comparison, protostomes ( C. farreri, D. pluex, D. melanogaster) contained more CYP genes than deuterostomes ( S. purpuratus and vertebrates) in Clan 2 but less genes in Clan 3 and Clan 4. Our findings will aid to deciphering CYP function and evolution in scallops and bivalves.

  20. Marine Toxin Okadaic Acid Affects the Immune Function of Bay Scallop (Argopecten irradians).

    PubMed

    Chi, Cheng; Giri, Sib Sankar; Jun, Jin Woo; Kim, Hyoun Joong; Yun, Saekil; Kim, Sang Guen; Park, Se Chang

    2016-01-01

    Okadaic acid (OA) is produced by dinoflagellates during harmful algal blooms and is a diarrhetic shellfish poisoning toxin. This toxin is particularly problematic for bivalves that are cultured for human consumption. This study aimed to reveal the effects of exposure to OA on the immune responses of bay scallop, Argopecten irradians. Various immunological parameters were assessed (total hemocyte counts (THC), reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH), lactate dehydrogenase (LDH), and nitric oxide (NO) in the hemolymph of scallops at 3, 6, 12, 24, and 48 h post-exposure (hpe) to different concentrations of OA (50, 100, and 500 nM). Moreover, the expression of immune-system-related genes (CLT-6, FREP, HSP90, MT, and Cu/ZnSOD) was also measured. Results showed that ROS, MDA, and NO levels and LDH activity were enhanced after exposure to different concentrations of OA; however, both THC and GSH decreased between 24-48 hpe. The expression of immune-system-related genes was also assessed at different time points during the exposure period. Overall, our results suggest that exposure to OA had negative effects on immune system function, increased oxygenic stress, and disrupted metabolism of bay scallops. PMID:27563864

  1. Reducing scalloping in synthetic aperture radar images using a composite image transform

    NASA Astrophysics Data System (ADS)

    Landmark, Knut; Solberg, Anne H. S.

    2015-10-01

    In burst mode SAR imaging, echo intensity depends on the target's azimuth position in the antenna pattern. As a result, an amplitude modulation known as scalloping may appear, particularly in ScanSAR images of ocean areas. A denoising method, recently developed for multibeam bathymetry, can be used to reduce residual scalloping in ScanSAR images. The algorithm is analogous to a band-stop filter in the frequency domain. Here, the transform is the composition of an edge detection operator and a discrete Radon transform (DRT). The edge operator accentuates fine-scale intensity changes; the DRT focuses linear features, as each DRT component is the sum of pixel intensities along a linear graph. A descalloping filter is implemented in the DRT domain by suppressing the range direction. The restored image is obtained by applying the inverse composite transform. First, a rapidly converging iterative pseudo-inverse DRT is computed. The edge operator is a spatial filter based on a discrete approximation of the Laplace operator, but modified to make the operator invertible. The method was tested on ocean scene ScanSAR images from the Envisat Advanced Synthetic Aperture Radar. The scalloping effect was significantly reduced, with no apparent distortion or smoothing of physical features.

  2. Offshore Habitat Preference of Overwintering Juvenile and Adult Black Sea Bass, Centropristis striata, and the Relationship to Year-Class Success.

    PubMed

    Miller, Alicia S; Shepherd, Gary R; Fratantoni, Paula S

    2016-01-01

    Black sea bass (Centropristis striata) migrations are believed to play a role in overwinter survival and connectivity between juvenile and adult populations. This study investigated oceanographic drivers of winter habitat choice and regional differences between populations of juvenile and adult black sea bass. Trends in cohort strength, as a result of juvenile survival, were also identified. Oceanographic and fisheries survey data were analyzed using generalized additive models. Among the oceanographic variables investigated, salinity was the main driver in habitat selection with an optimal range of 33-35 practical salinity units (PSU) for both juveniles and adults. Preferred temperature ranges varied between juveniles and adults, but held a similar minimum preference of >8°C. Salinity and temperature ranges also differed by regions north and south of Hudson Canyon. Shelf water volume had less of an effect than temperature or salinity, but showed an overall negative relationship with survey catch. The effect of winter conditions on juvenile abundance was also observed across state and federal survey index trends. A lack of correlation observed among surveys in the fall paired with a strong correlation in the spring identifies the winter period as a factor determining year-class strength of new recruits to the population. A rank order analysis of spring indices identified three of the largest year classes occurring during years with reduced shelf water volumes, warmer winter shelf waters, and a 34 PSU isohaline aligned farther inshore. While greater catches of black sea bass in the northwest Atlantic Ocean remain south of Hudson Canyon, the species' range has expanded north in recent years. PMID:26824350

  3. Offshore Habitat Preference of Overwintering Juvenile and Adult Black Sea Bass, Centropristis striata, and the Relationship to Year-Class Success

    PubMed Central

    Miller, Alicia S.; Shepherd, Gary R.; Fratantoni, Paula S.

    2016-01-01

    Black sea bass (Centropristis striata) migrations are believed to play a role in overwinter survival and connectivity between juvenile and adult populations. This study investigated oceanographic drivers of winter habitat choice and regional differences between populations of juvenile and adult black sea bass. Trends in cohort strength, as a result of juvenile survival, were also identified. Oceanographic and fisheries survey data were analyzed using generalized additive models. Among the oceanographic variables investigated, salinity was the main driver in habitat selection with an optimal range of 33–35 practical salinity units (PSU) for both juveniles and adults. Preferred temperature ranges varied between juveniles and adults, but held a similar minimum preference of >8°C. Salinity and temperature ranges also differed by regions north and south of Hudson Canyon. Shelf water volume had less of an effect than temperature or salinity, but showed an overall negative relationship with survey catch. The effect of winter conditions on juvenile abundance was also observed across state and federal survey index trends. A lack of correlation observed among surveys in the fall paired with a strong correlation in the spring identifies the winter period as a factor determining year-class strength of new recruits to the population. A rank order analysis of spring indices identified three of the largest year classes occurring during years with reduced shelf water volumes, warmer winter shelf waters, and a 34 PSU isohaline aligned farther inshore. While greater catches of black sea bass in the northwest Atlantic Ocean remain south of Hudson Canyon, the species’ range has expanded north in recent years. PMID:26824350

  4. Chromosomal mapping of tandem repeats in the Yesso Scallop, Patinopecten yessoensis (Jay, 1857), utilizing fluorescence in situ hybridization

    PubMed Central

    Li, Xuan; Yang, Zujing; Liao, Huan; Zhang, Zhengrui; Huang, Xiaoting; Bao, Zhenmin

    2016-01-01

    Abstract Construction of cytogenetic maps can provide important information for chromosome identification, chromosome evolution and genomic research. However, it hasn’t been conducted in many scallop species yet. In the present study, we attempted to map 12 fosmid clones containing tandem repeats by fluorescence in situ hybridization (FISH) in the Yesso scallop Patinopecten yessoensis (Jay, 1857). The results showed 6 fosmid clones were successfully mapped and distributed in 6 different pairs of chromosomes. Three clones were respectively assigned to a pair of metacentric chromosomes, a pair of submetacentric chromosomes and a pair of telocentric chromosomes and the remaining 3 clones showed their loci on three different pairs of subtelocentric chromosomes by co-hybridization. In summary, totally 8 pairs of chromosomes of the Yesso scallop were identified by 6 fosmid clones and two rDNA probes. Furthermore, 6 tandem repeats of 5 clones were sequenced and could be developed as chromosome specific markers for the Yesso scallop. The successful localization of fosmid clones will undoubtedly facilitate the integration of linkage groups with cytogenetic map and genomic research for the Yesso scallop. PMID:27186345

  5. Dynamics of the abundance of some bivalve species in Russian waters of the Sea of Japan and its prognosis

    NASA Astrophysics Data System (ADS)

    Gabaev, D. D.

    2009-04-01

    The abundance dynamics of several species of bivalve mollusks spats were studied on scallop collectors situated in Minonosok bay of Pos’eta Gulf for 27 years and for 4 years in Kit bay of the Sea of Japan (Russia). A significant positive relation was found between the species having similar thermopathy: the Japanese scallop Mizuhopecten yessoensis and Swift’s scallop Swiftopecten swifti, as well as between the wrinkled rock borer Hiatella arctica and Swift’s scallop Swiftopecten swifti. A significant reverse relation was found between the bay mussel Mytilus trossulus and the Northern Pacific seastar Asterias amurensis. Some of the studied mollusks of Minonosok bay and the remote Kit bay display a significant reversed interrelation in their abundance dynamics caused by the precipitation regime. The one-way dispersion analysis a revealed significant influence of the water temperature in June and the precipitation abundance in the summer on Swift’s scallop’s dynamic abundance. The two-way dispersion analysis showed a significant influence of the ice period duration and the solar activity expressed in Wolf’s numbers on the Japanese scallop abundance dynamics. The uneven years in the period from 1977 to 1984 were usually productive for M. yessoensis and S. swifti spat. After 1985, the even years became more productive (there was asynchronicity in the abundance dynamics compared with 1977-1984). Such asynchronicity appeared with the advent of the new 22-year solar cycle, which caused a change in the magnet polarity in 1986.

  6. Behavioural response of adult sea lamprey (Petromyzon marinus) to predator and conspecific alarm cues: evidence of additive effects

    USGS Publications Warehouse

    Di Rocco, Richard T; Imre, Istvan; Johnson, Nicholas; Brown, Grant B

    2015-01-01

    Sea lampreys Petromyzon marinus, an invasive pest in the Upper Great Lakes, avoid odours that represent danger in their habitat. These odours include conspecific alarm cues and predator cues, like 2-phenylethylamine hydrochloride (PEA HCl), which is found in the urine of mammalian predators. Whether conspecific alarm cues and predator cues function additively or synergistically when mixed together is unknown. The objectives of this experimental study were to determine if the avoidance response of sea lamprey to PEA HCl is proportional to the concentration delivered, and if the avoidance response to the combination of a predator cue (PEA HCl) and sea lamprey alarm cue is additive. To accomplish the first objective, groups of ten sea lampreys were placed in an artificial stream channel and presented with stepwise concentrations of PEA HCl ranging from 5 × 10−8 to 5 × 10−10 M and a deionized water control. Sea lampreys exhibited an increase in their avoidance behaviour in response to increasing concentrations of PEA HCl. To accomplish the second objective, sea lampreys were exposed to PEA HCl, conspecific alarm cue and a combination of the two. Sea lampreys responded to the combination of predator cue and conspecific alarm cue in an additive manner.

  7. Characterization of three mitogen-activated protein kinases (MAPK) genes reveals involvement of ERK and JNK, not p38 in defense against bacterial infection in Yesso scallop Patinopecten yessoensis.

    PubMed

    Sun, Yan; Zhang, Lingling; Zhang, Meiwei; Li, Ruojiao; Li, Yangping; Hu, Xiaoli; Wang, Shi; Bao, Zhenmin

    2016-07-01

    Mitogen-activated protein kinases (MAPKs) are protein Ser/Thr kinases that play a vital role in innate immune responses by converting extracellular stimuli into a wide range of cellular responses. Although MAPKs have been extensively studied in various vertebrates and invertebrates, our current understanding of MAPK signaling cascade in scallop is in its infancy. In this study, three MAPK genes (PyERK, PyJNK, and Pyp38) were identified from Yesso scallop Patinopecten yessoensis. The open reading frame of PyERK, PyJNK, and Pyp38 was 1104, 1227, and 1104 bp, encoding 367, 408, and 367 amino acids, respectively. Conservation in some splicing sites was revealed across the three PyMAPKs, suggesting the common descent of MAPKs genes. The expression profiles of PyMAPKs over the course of ten different developmental stages showed that they had different expression patterns. In adult scallops, PyMAPKs were primarily expressed in muscles, hemocytes, gill, and mantle. To gain insights into their role in innate immunity, we investigated their expression profiles after infection with Gram-positive bacteria (Micrococcus luteus) and Gram-negative bacteria (Vibrio anguillarum). Significant difference in gene expression was only found in PyERK and PyJNK, but not Pyp38, suggesting Pyp38 may not participate in immune response to bacterial infection. Besides, PyERK and PyJNK exhibited more drastic change against the invasion of V. anguillarum than M. luteus, suggesting they could be more sensitive to Gram-negative bacteria than Gram-positive bacteria. This study provides valuable resource for elucidating the role of MAPK signal pathway in bivalve innate immune response. PMID:27155450

  8. A STAGE-BASED POPULATION MODEL FOR BAY SCALLOPS (ARGOPECTEN IRRADIANS) AND IMPLICATIONS FOR POPULATION-LEVEL EFFECTS OF HABITAT ATLERATION.

    EPA Science Inventory

    Bay scallops (Argopecten irradians) inhabit shallow subtidal habitats along the Atlantic coast of the United States and require settlement substrates, such as submerged aquatic vegetation (SAV), for their early juvenile stages. The short lifespan of bay scallops (1-2 yr) coupled...

  9. Spatial changes in fatty acids signatures of the great scallop Pecten maximus across the Bay of Biscay continental shelf

    NASA Astrophysics Data System (ADS)

    Nerot, Caroline; Meziane, Tarik; Schaal, Gauthier; Grall, Jacques; Lorrain, Anne; Paulet, Yves-Marie; Kraffe, Edouard

    2015-10-01

    The spatial variability of food resources along continental margins can strongly influence the physiology and ecology of benthic bivalves. We explored the variability of food sources of the great scallop Pecten maximus, by determining their fatty acid (FA) composition along an inshore-offshore gradient in the Bay of Biscay (from 15 to 190 m depth). The FA composition of the digestive gland showed strong differences between shallow and deep-water habitats. This trend was mainly driven by their content in diatom-characteristic fatty acids, which are abundant near the coast. Scallops collected from the middle of the continental shelf were characterized by higher contents of flagellate markers than scallops from shallow habitats. This could be related to a permanent vertical stratification in the water column, which reduced vertical mixing of waters, thereby enhancing organic matter recycling through the microbial loop. In the deeper water station (190 m), FA compositions were close to the compositions found in scallops from shallow areas, which suggest that scallops could have access to the same resources (i.e. diatoms). Muscle FA composition was more indicative of the physiological state of scallops over this depth range, revealing contrasting reproductive strategies among the two coastal sites and metabolic or physiological adaptation at greater depth (e.g. structural and functional adjustments of membrane composition). This study therefore revealed contrasted patterns between shallow and deeper habitats for both P. maximus muscle and digestive gland tissues. This emphasizes the variability in the diet of this species along its distribution range, and stresses the importance of analyzing different tissues for their FA composition in order to better understand their physiology and ecology.

  10. Seasonal Variations Preserved in an Extinct Neogene Scallop, Chesapecten, from Florida to Delaware, USA and its Implications for Paleobiogeography

    NASA Astrophysics Data System (ADS)

    Goewert, A. E.; Surge, D.

    2007-12-01

    High-resolution records of climate variability on deep-time scales are needed to advance our understanding of the impact of a warming climate on seasonality and ecological change along a latitudinal gradient. The Middle Pliocene Warm Interval (MPWI: 3.2-2.8 Ma) provides insight into a globally warmer world, in which, relative to today, continental and oceanic configurations and atmospheric CO2 levels were similar; sea and continental ice were reduced; and interiors of continents were arid. Accretionary hard parts of marine organisms serve as physical (growth lines and increments) and chemical (87Sr/86Sr, δ18 O and δ13C) archives of life history, ecology, and environmental conditions during the life of the animal. Our goal was to examine variations in seasonality across latitudinal (~27° to37°N) and biogeographic (tropical to cold-­temperate) gradients of the Middle Atlantic Coastal Plain (MACP) during two intervals of warming: the Middle Miocene Climate Optimum (MMCO: 17-­15 Ma) and the Middle Pliocene Warm Interval (MPWI: 3.2-2.8 Ma). We analyzed variations in annual shell growth and isotope ratios (87Sr/86Sr, δ18O and δ13C) of 12 Chesapecten shells from the extremes of their biogeographic range (tropical to warm- temperate) (MMCO: Florida and Delaware; and MPWI: Florida and Virginia). Today, Florida is warm-temperate, and Delaware and Virginia are cold-temperate. Chesapecten are an extinct genus of scallop commonly preserved in MAPC deposits. They inhabited subtidal marine environments during the Miocene and Pliocene. We used 87Sr/86Sr ratios to tightly refine the timing and modeled age of the MMCO and MPWI. Modeled ages across Chesapecten's biogeographic extremes include: Florida (MMCO) 15.5 to 14.1±0.6 Ma; Delaware (MMCO) 18.0 to 17.5±0.4 Ma; Florida (MPWI) 3.75 to 2.05±0.9 Ma; and Virginia (MPWI) 2.45 to 1.65±0.4 Ma. We estimated seasonal temperature from the δ18O time series assuming interglacial δ18OSEAWATER values of -0.05‰ and -0.35‰ for

  11. Biomineralization changes with food supply confer juvenile scallops (Argopecten purpuratus) resistance to ocean acidification.

    PubMed

    Ramajo, Laura; Marbà, Núria; Prado, Luis; Peron, Sophie; Lardies, Marco A; Rodriguez-Navarro, Alejandro B; Vargas, Cristian A; Lagos, Nelson A; Duarte, Carlos M

    2016-06-01

    Future ocean acidification (OA) will affect physiological traits of marine species, with calcifying species being particularly vulnerable. As OA entails high energy demands, particularly during the rapid juvenile growth phase, food supply may play a key role in the response of marine organisms to OA. We experimentally evaluated the role of food supply in modulating physiological responses and biomineralization processes in juveniles of the Chilean scallop, Argopecten purpuratus, that were exposed to control (pH ~ 8.0) and low pH (pH ~ 7.6) conditions using three food supply treatments (high, intermediate, and low). We found that pH and food levels had additive effects on the physiological response of the juvenile scallops. Metabolic rates, shell growth, net calcification, and ingestion rates increased significantly at low pH conditions, independent of food. These physiological responses increased significantly in organisms exposed to intermediate and high levels of food supply. Hence, food supply seems to play a major role modulating organismal response by providing the energetic means to bolster the physiological response of OA stress. On the contrary, the relative expression of chitin synthase, a functional molecule for biomineralization, increased significantly in scallops exposed to low food supply and low pH, which resulted in a thicker periostracum enriched with chitin polysaccharides. Under reduced food and low pH conditions, the adaptive organismal response was to trade-off growth for the expression of biomineralization molecules and altering of the organic composition of shell periostracum, suggesting that the future performance of these calcifiers will depend on the trajectories of both OA and food supply. Thus, incorporating a suite of traits and multiple stressors in future studies of the adaptive organismal response may provide key insights on OA impacts on marine calcifiers. PMID:26644007

  12. Cflec-5, a pattern recognition receptor in scallop Chlamys farreri agglutinating yeast Pichia pastoris.

    PubMed

    Zhang, Huan; Kong, Pengfei; Wang, Lingling; Zhou, Zhi; Yang, Jialong; Zhang, Ying; Qiu, Limei; Song, Linsheng

    2010-07-01

    C-type lectins are a superfamily of carbohydrate-recognition proteins which play crucial roles as pattern recognition receptors (PRRs) in the innate immunity. In this study, the full-length cDNA of a C-type lectin was cloned from scallop Chlamys farreri (designated as Cflec-5) by expression sequence tag (EST) analysis and rapid amplification of cDNA ends (RACE) approach. The full-length cDNA of Cflec-5 was of 1412 bp. The open reading frame encoded a polypeptide of 153 amino acids, including a signal sequence and a conserved carbohydrate-recognition domain with the EPN motif determining the mannose-binding specificity. The deduced amino acid sequence of Cflec-5 showed high similarity to members of C-type lectin superfamily. The quantitative real-time PCR was performed to investigate the tissue distribution of Cflec-5 mRNA and its temporal expression profiles in hemocytes post pathogen-associated molecular patterns (PAMPs) stimulation. In healthy scallops, the Cflec-5 mRNA was mainly detected in gill and mantle, and marginally in other tissues. The mRNA expression of Cflec-5 could be significantly induced by lipopolysaccharide (LPS) and glucan stimulation and reached the maximum level at 6 h and 12 h, respectively. But its expression level did not change significantly during peptidoglycan (PGN) stimulation. The function of Cflec-5 was investigated by recombination and expression of the cDNA fragment encoding its mature peptide in Escherichia coli Rosetta Gami (DE3). The recombinant Cflec-5 agglutinated Pichia pastoris in a calcium-independent way. The agglutinating activity could be inhibited by d-mannose, LPS and glucan, but not by d-galactose or PGN. These results collectively suggested that Cflec-5 was involved in the innate immune response of scallops and might contribute to nonself-recognition through its interaction with various PAMPs. PMID:20211738

  13. Effect of fouling organisms on food uptake and nutrient release of scallop ( Chlamys nobilis, Reeve) cultured in Daya Bay

    NASA Astrophysics Data System (ADS)

    Su, Zhenxia; Xiao, Hui; Yan, Yan; Huang, Liangmin

    2008-02-01

    Biofouling is an important factor that affects the bivalve farming industry. Fouling organisms may reduce growth and survival rate of the cultured species. Fouler are often filter feeders, so they are potential competitors for food resource with the cultured species. The present study was conducted to measure the impact of fouling on food uptake and nutrient release in April and June, 2006 in Daya Bay near Guangzhou, China. Results showed that fouling organisms had significant effect on food uptake and nutrient release. The chlorophyll a uptake rate of fouled scallops was 7.53Lh-1±1.416Lh-1 and 11.94Lh-1±2.497Lh-1 in April and June, respectively, significantly higher than those of cleaned scallops, i.e., 4.23Lh-1±2.744Lh-1 and 2.57Lh-1±1.832Lh-1 respectively. The consumption of total particulate matter by fouled scallops in April and June was 5.52Lh-1±0.818Lh-1 and 3.07Lh-1±0.971Lh-1, respectively; the corresponding results for cleaned scallops are 2.49Lh-1±0.614Lh-1 and 2.37±1.214Lh-1, respectively. Fouling increased ammonia release significantly. The ammonia release rate of fouled scallops was 33.81Lh-1±7.699Lh-1 and 76.39Lh-1±9.251Lh-1 in April and June, while cleaned scallops released 2.46Lh-1±0.511Lh-1 and 7.23Lh-1±1.026Lh-1 ammonia, respectively. Phosphate release of fouled scallops was 22.72Lh-1±9.978Lh-1 in June and cleaned scallops released phosphate 6.01Lh-1±0.876Lh-1 in April. Therefore, fouling contributed much to food reduction and concentration increase of ammonia and phosphate in water.

  14. A novel multi-domain C1qDC protein from Zhikong scallop Chlamys farreri provides new insights into the function of invertebrate C1qDC proteins.

    PubMed

    Wang, Leilei; Wang, Lingling; Zhang, Daoxiang; Jiang, Qiufen; Sun, Rui; Wang, Hao; Zhang, Huan; Song, Linsheng

    2015-10-01

    The C1q domain containing (C1qDC) proteins are a family of proteins possessing globular C1q (gC1q) domains, and they rely on this domain to recognize various ligands such as PAMPs, immunoglobulins, ligands on apoptotic cell. In the present study, a novel multi-domain C1qDC protein (CfC1qDC-2) was identified from scallop Chlamys farreri, and its full length cDNA was composed of 1648 bp, encoding a signal peptide and three typical gC1q domains. BLAST analysis revealed significant sequence similarity between CfC1qDC-2 and C1qDC proteins from mollusks. Three gC1q domains were predicted in its tertiary structure to form a tightly packed bell-shaped trimer, and each one adopted a typical 10-stranded sandwich fold with a jelly-roll topology and contained six aromatic amino acids forming the hydrophobic core. The mRNA transcripts of CfC1qDC-2 were mainly detected in the tissues of hepatopancreas and gonad of adult scallops, and the expression level was up-regulated in hemocytes after stimulated by LPS, PGN and β-glucan. During the embryonic development of scallop, the mRNA transcripts of CfC1qDC-2 were presented in all the detected stages, and the expression level was up-regulated from D-hinged larvae and reached the highest at eye-spot larvae. The recombinant protein of MBP-CfC1qDC-2 (rCfC1qDC-2) could bind various PAMPs including LPS, PGN, LTA, β-glucan, mannan as well as polyI:C, and different microorganisms including three Gram-negative bacteria, three Gram-positive bacteria and two yeasts, as well as scallop apoptotic cells. Meanwhile, rCfC1qDC-2 could interact with human heat-aggregated IgG and IgM, and inhibit the C1q-dependent hemolysis of rabbit serum. All these results indicated that CfC1qDC-2 could recognize not only PAMPs as a PRR, but also the apoptotic cells. Moreover, the similar structures and functions shared by CfC1qDC-2 and complement C1q provided a new insight into the evolution of C1qDC proteins in complement system. PMID:26049063

  15. Formation and Evolution of Scalloped Depressions on Malea Planum and the southern rim of the Hellas Basin, Mars

    NASA Astrophysics Data System (ADS)

    Zanetti, M.; Hiesinger, H.; Reiss, D.; Neukum, G.

    2008-09-01

    Introduction: Scalloped depressions are an erosional surface morphology characterized as a type of dissected mantle terrain by Milliken and Mustard [1]. They are identified by their asymmetrical north-south profile which shows a steep pole-facing scarp, a flat floor, and a gentle equator-facing slope which grades into the surrounding terrain [1]. They are found in latitudedependent, ice-rich surface mantles in both the northern and southern hemispheres [1]. The mantle material is presumably composed of atmospherically derived dust and water ice, and is thought to be related to obliquity-driven ice activity as recently as 2.1-0.4 Myr ago [3]. Previous researchers, [e.g. 1,2,4-7] have attributed the formation of scallops to the sublimation of interstitial ice. Morgenstern et al. [6] suggested that the asymmetric profile of scallops can be explained by enhanced solar insolation on the equator-facing slope which leads to enhanced sublimation of interstial ice and thereby increases the area of the depression. By this process they can also grow and coalesce to form large degraded areas [6]. Building on our previous work [7], we investigate this hypothesis using HiRISE and THEMIS-IR images. We also propose a hypothesis for the nucleation and evolution of scallops. Previous Work: Our previous work surveyed the southern hemisphere using HRSC images for the presence of scalloped terrain, and revealed that almost all scalloped terrains are in the Malea Planum region near the southern wall of the Hellas basin [7]. We mapped the distribution of scalloped terrain between 50° and 70° E and 50° and 70° S. The results of the map showed that the scalloped terrains contour the southern wall of the Hellas basin between the elevations of 1000 m and -2000 m, and that the icerich mantle is thickest in this region [7]. Data and Methods: High resolution HiRISE images of the scalloped terrain of Malea Planum were used to investigate small scale features. Daytime infrared images from

  16. Proteomic responses to hypoxia at different temperatures in the great scallop (Pecten maximus)

    PubMed Central

    Lacroix, Camille; Richard, Joëlle; Flye-Sainte-Marie, Jonathan; Bargelloni, Luca; Pichereau, Vianney

    2015-01-01

    Hypoxia and hyperthermia are two connected consequences of the ongoing global change and constitute major threats for coastal marine organisms. In the present study, we used a proteomic approach to characterize the changes induced by hypoxia in the great scallop, Pecten maximus, subjected to three different temperatures (10 °C, 18 °C and 25 °C). We did not observe any significant change induced by hypoxia in animals acclimated at 10 °C. At 18 °C and 25 °C, 16 and 11 protein spots were differentially accumulated between normoxia and hypoxia, respectively. Moreover, biochemical data (octopine dehydrogenase activity and arginine assays) suggest that animals grown at 25 °C switched their metabolism towards anaerobic metabolism when exposed to both normoxia and hypoxia, suggesting that this temperature is out of the scallops’ optimal thermal window. The 11 proteins identified with high confidence by mass spectrometry are involved in protein modifications and signaling (e.g., CK2, TBK1), energy metabolism (e.g., ENO3) or cytoskeleton (GSN), giving insights into the thermal-dependent response of scallops to hypoxia. PMID:25861557

  17. Biological effects of mechanically and chemically dispersed oil on the Icelandic scallop (Chlamys islandica).

    PubMed

    Frantzen, Marianne; Regoli, Francesco; Ambrose, William G; Nahrgang, Jasmine; Geraudie, Perrine; Benedetti, Maura; Locke, William L; Camus, Lionel

    2016-05-01

    This study aimed to simulate conditions in which dispersant (Dasic NS) might be used to combat an oil spill in coastal sub-Arctic water of limited depth and water exchange in order to produce input data for Net Environmental Benefit Analysis (NEBA) of Arctic and sub-Arctic coastal areas. Concentration dependent differences in acute responses and long-term effects of a 48h acute exposure to dispersed oil, with and without the application of a chemical dispersant, were assessed on the Arctic filter feeding bivalve Chlamys islandica. Icelandic scallops were exposed for 48h to a range of spiked concentrations of mechanically and chemically dispersed oil. Short-term effects were assessed in terms of lysosomal membrane stability, superoxide dismutase, catalase, gluthatione S-transferases, glutathione peroxidases, glutathione reductase, glutathione, total oxyradical scavenging capacity, lipid peroxidation and peroxisomal proliferation. Post-exposure survival, growth and reproductive investment were followed for 2 months to evaluate any long-term consequence. Generally, similar effects were observed in scallops exposed to mechanically and chemically dispersed oil. Limited short-term effects were observed after 48h, suggesting that a different timing would be required for measuring the possible onset of such effects. There was a concentration dependent increase in cumulative post-exposure mortality, but long-term effects on gonadosomatic index, somatic growth/condition factor did not differ among treatments. PMID:26809079

  18. Effect of the Algaecide Palmitoleic Acid on the Immune Function of the Bay Scallop Argopecten irradians.

    PubMed

    Chi, Cheng; Giri, Sib Sankar; Jun, Jin Woo; Kim, Hyoun Joong; Kim, Sang Guen; Yun, Saekil; Park, Se Chang

    2016-01-01

    Palmitoleic acid (PA), an algicidal compound, is used against the toxin producing dinofagelate Alexandrium tamarense, however, its impact on the edible bay scallop (Argopecten irradians) is still unclear. Therefore, we investigated the impacts of effective algicidal concentrations (20, 40, and 80 mg/L) of PA on immune responses in A. irradians. Various immune parameters including acid phosphatase (ACP) activity, superoxide dismutase (SOD), lysozyme, phagocytic activity, total protein, malondialdehyde (MDA) level, and reactive oxygen species (ROS) production and the expression of immune-related genes (PrxV, CLT-6, MT, and BD) were measured at 3, 6, 12, 24, and 48 h post-exposure (hpe) to PA. Lysozyme activity was lower in scallops at 12-48 hpe to 80 mg/L. SOD, ACP activity, ROS production, the total protein, and MDA level was higher at 12 to 48 hpe with different concentrations of PA. Phagocytic activity increased at 6-12 hpe to 40-80 mg/L of PA, but decreased at 24-48 hpe. The expressions of genes PrxV, CLT-6, MT and BD down-regulated at 3 hpe were observed, while differential expressions from 6-48 hpe with different concentrations of PA. The present study demonstrated that immersing A. irradians in PA at effective concentrations could result in differential effects on non-specific immune responses and expressions of immune-related genes. PMID:27171074

  19. Crawling scallop: friction-based locomotion with one degree of freedom.

    PubMed

    Wagner, Gregory L; Lauga, Eric

    2013-05-01

    Fluid-based locomotion at low Reynolds number is subject to the constraints of the scallop theorem, which dictate that body kinematics identical under a time-reversal symmetry (in particular, those with a single degree of freedom) cannot display locomotion on average. The implications of the theorem naturally compel one to ask whether similar symmetry constraints exist for locomotion in different environments. In this work we consider locomotion along a surface where forces are described by isotropic Coulomb friction. To address whether motions with a single degree of freedom can lead to transport, we analyze a model system consisting of two bodies whose separation distance undergoes periodic time variations. The behavior of the two-body system is entirely determined by the kinematic specification of their separation, the friction forces, and the mass of each body. We show that the constraints of the scallop theorem can be escaped in frictional media if two asymmetry conditions are met at the same time: the frictional forces of each body against the surface must be distinct and the time-variation of the body-body separation must vary asymmetrically in time (so quick-slow or slow-quick in the extension-contraction phases). Our results are demonstrated numerically and interpreted using asymptotic expansions. PMID:23419503

  20. Evaluation of the 2b-RAD method for genomic selection in scallop breeding.

    PubMed

    Dou, Jinzhuang; Li, Xue; Fu, Qiang; Jiao, Wenqian; Li, Yangping; Li, Tianqi; Wang, Yangfan; Hu, Xiaoli; Wang, Shi; Bao, Zhenmin

    2016-01-01

    The recently developed 2b-restriction site-associated DNA (2b-RAD) sequencing method provides a cost-effective and flexible genotyping platform for aquaculture species lacking sufficient genomic resources. Here, we evaluated the performance of this method in the genomic selection (GS) of Yesso scallop (Patinopecten yessoensis) through simulation and real data analyses using six statistical models. Our simulation analysis revealed that the prediction accuracies obtained using the 2b-RAD markers were slightly lower than those obtained using all polymorphic loci in the genome. Furthermore, a small subset of markers obtained from a reduced tag representation (RTR) library presented comparable performance to that obtained using all markers, making RTR be an attractive approach for GS purpose. Six GS models exhibited variable performance in prediction accuracy depending on the scenarios (e.g., heritability, sample size, population structure), but Bayes-alphabet and BLUP-based models generally outperformed other models. Finally, we performed the evaluation using an empirical dataset composed of 349 Yesso scallops that were derived from five families. The prediction accuracy for this empirical dataset could reach 0.4 based on optimal GS models. In summary, the genotyping flexibility and cost-effectiveness make 2b-RAD be an ideal genotyping platform for genomic selection in aquaculture breeding programs. PMID:26754638

  1. Variation in Size and Growth of the Great Scallop Pecten maximus along a Latitudinal Gradient

    PubMed Central

    Chauvaud, Laurent; Patry, Yann; Jolivet, Aurélie; Cam, Emmanuelle; Le Goff, Clement; Strand, Øivind; Charrier, Grégory; Thébault, Julien; Lazure, Pascal; Gotthard, Karl; Clavier, Jacques

    2012-01-01

    Understanding the relationship between growth and temperature will aid in the evaluation of thermal stress and threats to ectotherms in the context of anticipated climate changes. Most Pecten maximus scallops living at high latitudes in the northern hemisphere have a larger maximum body size than individuals further south, a common pattern among many ectotherms. We investigated differences in daily shell growth among scallop populations along the Northeast Atlantic coast from Spain to Norway. This study design allowed us to address precisely whether the asymptotic size observed along a latitudinal gradient, mainly defined by a temperature gradient, results from differences in annual or daily growth rates, or a difference in the length of the growing season. We found that low annual growth rates in northern populations are not due to low daily growth values, but to the smaller number of days available each year to achieve growth compared to the south. We documented a decrease in the annual number of growth days with age regardless of latitude. However, despite initially lower annual growth performances in terms of growing season length and growth rate, differences in asymptotic size as a function of latitude resulted from persistent annual growth performances in the north and sharp declines in the south. Our measurements of daily growth rates throughout life in a long-lived ectothermic species provide new insight into spatio-temporal variations in growth dynamics and growing season length that cannot be accounted for by classical growth models that only address asymptotic size and annual growth rate. PMID:22649553

  2. Formation of membrane ridges and scallops by the F-BAR protein Nervous Wreck

    PubMed Central

    Becalska, Agata N.; Kelley, Charlotte F.; Berciu, Cristina; Stanishneva-Konovalova, Tatiana B.; Fu, Xiaofeng; Wang, ShiYu; Sokolova, Olga S.; Nicastro, Daniela; Rodal, Avital A.

    2013-01-01

    Eukaryotic cells are defined by extensive intracellular compartmentalization, which requires dynamic membrane remodeling. FER/Cip4 homology-Bin/amphiphysin/Rvs (F-BAR) domain family proteins form crescent-shaped dimers, which can bend membranes into buds and tubules of defined geometry and lipid composition. However, these proteins exhibit an unexplained wide diversity of membrane-deforming activities in vitro and functions in vivo. We find that the F-BAR domain of the neuronal protein Nervous Wreck (Nwk) has a novel higher-order structure and membrane-deforming activity that distinguishes it from previously described F-BAR proteins. The Nwk F-BAR domain assembles into zigzags, creating ridges and periodic scallops on membranes in vitro. This activity depends on structural determinants at the tips of the F-BAR dimer and on electrostatic interactions of the membrane with the F-BAR concave surface. In cells, Nwk-induced scallops can be extended by cytoskeletal forces to produce protrusions at the plasma membrane. Our results define a new F-BAR membrane-deforming activity and illustrate a molecular mechanism by which positively curved F-BAR domains can produce a variety of membrane curvatures. These findings expand the repertoire of F-BAR domain mediated membrane deformation and suggest that unique modes of higher-order assembly can define how these proteins sculpt the membrane. PMID:23761074

  3. Regulation of glycolysis during acclimation of scallops (Patinopecten yessoensis Jay) to anaerobiosis.

    PubMed

    Enomoto, T; Nakao, C; Ohyama, H

    2000-09-01

    Some glycolytic metabolites in the adductor muscle were measured after transfer of scallops from aerobic to anaerobic saltwater for 12 h. The level of octopine increased gradually during the initial 3 h incubation, and thereafter the level increased rapidly up to 12 h. The ATP level also did not show any significant change for the initial 3 h, and then decreased rapidly. The fructose 2,6-biphosphate (Fru 2,6-BP) level increased drastically during the initial 3 h incubation, but thereafter the level did not show any significant change up to 12 h. In the short-term effects of anaerobiosis for 90 min, the level of fructose 6-phosphate (Fru 6-P) increased just after transfer to anaerobiosis, and then its level decreased. In contrast, the fructose 1,6-biphosphate (Fru 1,6-BP) level increased greatly, at the time when both glucose 6-phosphate (Glc 6-P) and Fru 6-P decreased. The Fru 2,6-BP level did not any significant change during the initial 15 min incubation, but thereafter the level increased gradually up to 90 min. Scallop 6-phosphofructo 1-kinase (EC 2.7.1.11) (PFK1) was strongly activated by 1 microM Fru 2,6-BP when 0.2 mM Fru 6-P was used as a substrate, but the activity was not affected at 5 mM Fru 6-P. In view of these results, the regulation mechanism of glycolysis is discussed. PMID:11126751

  4. Development of 101 novel EST-derived single nucleotide polymorphism markers for Zhikong scallop ( Chlamys farreri)

    NASA Astrophysics Data System (ADS)

    Li, Jiqin; Bao, Zhenmin; Li, Ling; Wang, Xiaojian; Wang, Shi; Hu, Xiaoli

    2013-09-01

    Zhikong scallop ( Chlamys farreri) is an important maricultured species in China. Many researches on this species, such as population genetics and QTL fine-mapping, need a large number of molecular markers. In this study, based on the expressed sequence tags (EST), a total of 300 putative single nucleotide polymorphisms (SNPs) were selected and validated using high resolution melting (HRM) technology with unlabeled probe. Of them, 101 (33.7%) were found to be polymorphic in 48 individuals from 4 populations. Further evaluation with 48 individuals from Qingdao population showed that all the polymorphic loci had two alleles with the minor allele frequency ranged from 0.046 to 0.500. The observed and expected heterozygosities ranged from 0.000 to 0.925 and from 0.089 to 0.505, respectively. Fifteen loci deviated significantly from Hardy-Weinberg equilibrium and significant linkage disequilibrate was detected in one pair of markers. BLASTx gave significant hits for 72 of the 101 polymorphic SNP-containing ESTs. Thirty four polymorphic SNP loci were predicted to be non-synonymous substitutions as they caused either the change of codons (33 SNPs) or pretermination of translation (1 SNP). The markers developed can be used for the population studies and genetic improvement on Zhikong scallop.

  5. Antitumor glycogen from scallops and the interrelationship of structure and antitumor activity.

    PubMed

    Takaya; Uchisawa; Ichinohe; Sasaki; Ishida; Matsue

    1998-12-01

    Hot water extract of scallop was treated with actinase E and fractionated by Sephadex G-25 gel-filtration and DEAE Sephadex A-25 ion-exchange chromatography. The antitumor activity of these fractions against Meth-A fibrosarcoma was examined. The nonadsorbed fraction (SCA25A) and weakly adsorbed fraction (SCA25B) obtained on DEAE Sephadex A-25 anion-exchange gel showed strong antitumor activity. Chemical analyses and NMR spectra identified SCA25A and SCA25B as glycogen. However, glycogen extracted from the scallop with trichloroacetic acid and from abalone showed no antitumor activity. This difference was thought to be due to variations in the fine structure of the glycogen molecule. The fine structure of glycogen was investigated by a sequential enzyme digestion method using beta-amylase and pullulanase, while the unit chain was analyzed by high performance anion exchange chromatography. The results showed that the antitumor active glycogen was highly branched with a shorter chain than glycogens without antitumor activity. PMID:9852612

  6. Shell damage in the Tehuelche scallop Aequipecten tehuelchus caused by Polydora rickettsi (Polychaeta: Spionidae) infestation.

    PubMed

    Diez, M E; Orensanz, J M; Márquez, F; Cremonte, F

    2013-10-01

    The different types of shell damage caused to the commercially valuable Tehuelche scallop (Aequipecten tehuelchus) by the polychaete Polydora rickettsi are described. X-rays, computerized tomography, shell sections, scanning electron microscopy, Energy Dispersive X-ray analysis (EDAX), mineralogical analyses and geometric morphometrics were applied to that end. Scallop shells presented three types of damage: (1) spots, (2) calcareous alterations, and (3) mud blisters. Microstructural alterations consisted of a simple conchiolin membranous layer in the case of spots, a series of interleaved layers of different degree of calcifications in calcareous alterations, and two different surface morphologies (muddy and mucous layers) in mud blisters. Damage was localized mainly along concentric growth rings, coincidentally with the location of most burrows, as shown by X-ray. Mineralogical analysis showed that in all cases (including non-infested shells) calcite was the calcium carbonate polymorph present. Geometric morphometrics showed that only 5% of shape variation was explained by infestation with P. rickettsi, irrespective of the type of damage. Number of worms per infested shell varied significantly among four beds. Left shells (upward-oriented) were significantly more affected than right shells, which are in closer contact with the bottom. PMID:23871854

  7. Accumulation, Biotransformation, Histopathology and Paralysis in the Pacific Calico Scallop Argopecten ventricosus by the Paralyzing Toxins of the Dinoflagellate Gymnodinium catenatum

    PubMed Central

    Escobedo-Lozano, Amada Y.; Estrada, Norma; Ascencio, Felipe; Contreras, Gerardo; Alonso-Rodriguez, Rosalba

    2012-01-01

    The dinoflagellate Gymnodinium catenatum produces paralyzing shellfish poisons that are consumed and accumulated by bivalves. We performed short-term feeding experiments to examine ingestion, accumulation, biotransformation, histopathology, and paralysis in the juvenile Pacific calico scallop Argopecten ventricosus that consume this dinoflagellate. Depletion of algal cells was measured in closed systems. Histopathological preparations were microscopically analyzed. Paralysis was observed and the time of recovery recorded. Accumulation and possible biotransformation of toxins were measured by HPLC analysis. Feeding activity in treated scallops showed that scallops produced pseudofeces, ingestion rates decreased at 8 h; approximately 60% of the scallops were paralyzed and melanin production and hemocyte aggregation were observed in several tissues at 15 h. HPLC analysis showed that the only toxins present in the dinoflagellates and scallops were the N-sulfo-carbamoyl toxins (C1, C2); after hydrolysis, the carbamate toxins (epimers GTX2/3) were present. C1 and C2 toxins were most common in the mantle, followed by the digestive gland and stomach-complex, adductor muscle, kidney and rectum group, and finally, gills. Toxin profiles in scallop tissue were similar to the dinoflagellate; biotransformations were not present in the scallops in this short-term feeding experiment. PMID:22822356

  8. Toxic effects upon exposure to polycyclic aromatic hydrocarbon (chrysene) in scallop Chlamys farreri during the reproduction period.

    PubMed

    Xiu, Meng; Pan, Luqing; Jin, Qian

    2016-06-01

    This study aims to investigate potential toxic effects of chrysene (CHR) on mature scallop Chlamys farreri during the reproduction period, using indicators of antioxidant defences and oxidative stress. Scallops were exposed to 0.2, 0.8 and 3.2μg/L waterborne CHR for 21 days, at day 10 scallops were induced to spawn. At days 1, 3, 6, 10, 11, 15 and 21, aryl hydrocarbon hydroxylase (AHH), 7-ethoxyresorufin-O-deethylase (EROD), glutathione-s-transferase (GST), glutathione (GSH), superoxide dismutase (SOD), lipid peroxidation (LPO), protein carbonyl (PC) and DNA strand breaks in digestive glands were examined by separately analysing male and female scallops. During the pre-spawn period, Levels of enzymatic activities and oxidative stress were all induced by the exposure to CHR for females and males. GST activity presented a good time- and dose-dependent relationship only in males, and GSH content showed a dose-dependent manner in both sexes. During the post-spawn period, different trends were observed, while PC contents maintained growth in time- and dose-dependent manner. Overall, males were more sensitive than females to CHR exposure in enzyme activities, and correspondingly, females suffered from more serious oxidative damages. Both GSH and PC contents seemed to be potential biomarkers for PAH exposure. These results will offer the information on toxicity of CHR in this species, and ensure the influence of gender and reproductive status on PAH detoxification metabolism. PMID:27131750

  9. DNA damage in the gill cells of the marine scallop Mizuhopecten yessoensis during anoxic stress and aerobic recovery

    NASA Astrophysics Data System (ADS)

    Slobodskova, Valentina V.; Zhukovskaya, Avianna F.; Chelomin, Victor P.

    2012-06-01

    Anoxia-induced DNA damage in the gill cells of the marine scallop Mizuhopecten yessoensis was assessed with the alkaline comet assay (single-cell gel electrophoresis). The alkaline comet assay method for detecting DNA strand breaks and alkali labile sites in individual cells. DNA damage was determened in the scallops ( M. yessoensis) gill cells. The scallops were exposed to air for 8 h showing a clear increase in the levels of DNA damage. After the air exposure, M. yessoensis were re-submersed for a period of 12 h, leading values to return to a pre-aerial exposure level. Control animals were kept immersed during the whole period. The resulting data demonstrate that natural influences, such as oxygen depletion (anoxia) in seawater, can be responsible for the induction of DNA damage. If the scallops were re-immersed in oxic conditions, the anoxically induced breaks were repaired. The main mechanisms influencing the integrity of the DNA structure are discussed in this paper.

  10. Analysis of histone gene expression in adult tissues of the sea urchins Strongylocentrotus purpuratus and Lytechinus pictus: tissue-specific expression of sperm histone genes.

    PubMed Central

    Lieber, T; Weisser, K; Childs, G

    1986-01-01

    We analyzed the histone mRNA population found in several adult tissues of the sea urchin Strongylocentrotus purpuratus and in testis of Lytechinus pictus. Unique species of H1 and H2b mRNAs encoding the sperm-specific histone subtypes can be found exclusively in testis RNA. S. purpuratus contains two distinct testis-specific H1 transcripts, while L. pictus contains one such transcript. Each of these mRNAs is larger than either early or late embryonic H1 mRNAs. Other somatic adult tissues contain transcripts derived from members of the late embryonic H1 histone gene family. S. purpuratus contains one H2b transcript found exclusively in testis, while L. pictus contains two such H2b mRNAs. Similarly, in tissues other than testis, late H2b transcripts were found. While there is no sperm-specific H2a protein, a limited set of late histone H2a genes encoding primarily the H2a-beta subtype is expressed in testis. The majority of the H2a protein found in diploid adult tissues is also the H2a-beta subtype; however, the size of the H2a transcripts differs between testis and other tissues. We conclude that different members of the late H2a gene family are differentially expressed in embryos and adult tissues. We prepared and characterized cDNA clones encoding the sperm-specific H2b protein as well as the H2a-beta protein found in testis. Images PMID:3785204

  11. Importance of kelp-derived organic carbon to the scallop Chlamys farreri in an integrated multi-trophic aquaculture system

    NASA Astrophysics Data System (ADS)

    Xu, Qiang; Gao, Fei; Yang, Hongsheng

    2016-03-01

    Bivalves and seaweeds are important cleaners that are widely used in integrated multi-trophic aquaculture (IMTA) systems. A beneficial relationship between seaweed and bivalve in the seaweed-based IMTA system has been confirmed, but the trophic importance of seaweed-derived particulate organic materials to the co-cultured bivalve is still unclear. We evaluated the trophic importance of the kelp Saccharina japonica to the co-cultured scallop Chlamys farreri in a typical IMTA farm in Sungo Bay (Weihai, North China). The dynamics of detritus carbon in the water were monitored during the culturing period. The proportion of kelp-derived organic matter in the diet of the co-cultured scallop was assessed via the stable carbon isotope method. Results showed that the detritus carbon in the water ranged from 75.52 to 265.19 μg/L, which was 25.6% to 73.8% of total particulate organic carbon (TPOC) during the study period. The amount of detritus carbon and its proportion in the TPOC changed throughout the culture cycle of the kelp. Stable carbon isotope analysis showed that the cultured scallop obtained 14.1% to 42.8% of its tissue carbon from the kelp, and that the percentages were closely correlated with the proportion of detritus carbon in the water ( F =0.993, P= 0.003). Evaluation showed that for 17 000 tons (wet weight) of annual scallop production, the kelp contributed about 139.3 tons of carbon (535.8 tons of dry mass). This confirms that cultured kelp plays a similar trophic role in IMTA systems as it does in a natural kelp bed. It is a major contributor to the detritus pool and supplies a vital food source to filter-feeding scallops in the IMTA system, especially during winter and early spring when phytoplankton are scarce.

  12. The immunomodulation of nicotinic acetylcholine receptor subunits in Zhikong scallop Chlamys farreri.

    PubMed

    Shi, Xiaowei; Zhou, Zhi; Wang, Lingling; Wang, Mengqiang; Shi, Shaoying; Wang, Zhen; Song, Linsheng

    2015-11-01

    Nicotinic acetylcholine receptor (nAChR), the best-studied ionotropic neuron receptor protein, is a key player in neuronal communication, and it has been reported to play an important role in immunomodulation of vertebrates. Although nAChRs have also been identified in most invertebrates, the knowledge about their immunomodulation is still limited. In the present study, two scallop nAChR genes were identified from Chlamys farreri (designed as CfnAChR1 and CfnAChR2), which encoded 384 and 443 amino acids, respectively. The conserved disulfide-linked cystines, ion selectivity residues and the hydrophobic gating residues (L251, V255 and V259) were identified in CfnAChR1 and CfnAChR2. The immunoreactivities of CfnAChR1 and CfnAChR2 were observed in all the tested scallop tissues, including adductor muscle, mantle, gill, hepatopancreas, kidney and gonad. After LPS (0.5 mg mL(-1)) stimulation, the expression of CfnAChR1 mRNA in haemocytes increased significantly by 9.83-fold (P < 0.05) and 12.93-fold (P < 0.05) at 3 h and 24 h, respectively. While the expression level of CfnAChR2 mRNA increased 43.94% at 12 h after LPS stimulation (P < 0.05). After TNF-α (50 ng mL(-1)) stimulation, the expression levels of CfnAChR1 and CfnAChR2 both increased significantly at 1 h, which were 21.33-fold (P < 0.05) and 2.44-fold (P < 0.05) of that in the PBS group, respectively. The results collectively indicated that the cholinergic nervous system in scallops could be activated by immune stimulations through CfnAChR1 and CfnAChR2, which function as the links between the cholinergic nervous system and immune system. PMID:26455648

  13. Scalloping Sacral Arachnoid Cyst as a Cause of Perianal Pain- A Case Report

    PubMed Central

    Tyagi, Himanshu Ravindra; Kalra, Kashmiri Lal; Acharya, Shankar; Singh, Rupinder Pal

    2014-01-01

    Introduction: Scalloping sacral arachnoid cyst though a rare condition, should be suspected in cases of persistent perianal pain without any obvious urological or anorectal pathology. Such difficult cases justify ordering an M.R.I of spine as plain X-Rays and clinical examination may come out to be inconclusive. X-ray in later stages may show changes corresponding to scalloping of bone due pressure effect of cyst on surrounding tissue. Diagnosis may further be confirmed by doing contrast MRI which differentiates arachnoid cyst from other intradural and extradural pathologies. Though anatomically spinal arachnoid cysts are just an out pouching from the spinal meningeal sac or nerve root sheath they may be extradural or intradural in their location, communicating to main C.S.F column through their pedicle or an ostium leading to continuous enlargement in size. Case Report: A 32 year old female was admitted under our spine unit with 1.5 year history of chronic pain, swelling and reduced sensation in perianal region. On examination she had tenderness and hypoesthesia over lower sacral region. The pain was continuous, dull aching in nature, not related to activity, localized over lower sacrum and perianal area. The neurological examination of her both lower limbs were unremarkable. Anal tone and anal reflex were normal. No sign of inflammation or tenderness was found over coccyx. Since the X-rays were inconclusive an MRI scan was done which showed a cystic lesion in the sacral area extending from S2 to S4 region with mechanical scalloping effect on the surrounding bone. The lesion had same intensity as C.S.F in both T1 &T2 weighted images. The treatment was done by way of surgical decompression with complete excision of cyst and obliteration of space by a posterior midline approach. Presently the patient is 1 year post operative and no sign of recurrence is there. Conclusion: Sacral arachnoid cysts should be considered as a differential diagnosis of perianal pain. Large

  14. First molluscan TNFR homologue in Zhikong scallop: molecular characterization and expression analysis.

    PubMed

    Li, Ling; Qiu, Limei; Song, Linsheng; Song, Xiaoyan; Zhao, Jianmin; Wang, Lingling; Mu, Changkao; Zhang, Huan

    2009-11-01

    Tumor necrosis factor receptors (TNFRs) are a superfamily of proteins characterized by the unique cysteine-rich domain (CRD) and their important roles in diverse physiological and pathological events such as inflammation, apoptosis, autoimmunity and organogenesis. The first member of the molluscan TNFR family, designated as CfTNFR, was identified from Zhikong scallop Chlamys farreri by expressed sequence tag (EST) and rapid amplification of cDNA ends (RACE) approaches. The full-length cDNA of CfTNFR was of 1334 bp, consisting of a 5' UTR of 17 bp, a 3' UTR of 69 bp with a poly (A) tail, and an open reading frame (ORF) of 1248 bp encoding a polypeptide of 415 amino acids with a theoretical isoelectric point of 8.33 and predicted molecular weight of 47.07 kDa. There were a signal peptide, a CRD, a transmembrane region and a death domain in the deduced amino acid sequence of CfTNFR, suggesting that it was a typical type I membrane protein. The high identities (22-40%) of CfTNFR with other TNFR superfamily members indicated that CfTNFR should be a member of TNFR superfamily, and moreover, it should be the first death domain-containing TNFR found in invertebrates. Phylogenetic analysis revealed that CfTNFR was closely related to TNFR-like proteins from Strongylocentrotus purpuratus, Drosophila melanogaster and Ciona intestinalis, and they formed a separate branch apart from vertebrate TNFRs. The spatial expression of CfTNFR transcripts in healthy and bacteria challenged scallops was examined by quantitative real-time PCR. CfTNFR transcripts could be detected in all tested tissues, including haemocytes, gonad, gill, mantle and hepatopancreas, and significantly up-regulated in the tissues of gonad, gill, mantle and hepatopancreas after Listonella anguillarum challenge, indicating that CfTNFR was constitutive and inducible acute-phase protein involved in immune defence. The present results suggested the existence of the TNFR-like molecules and TNF-TNFR system in low

  15. The Sp185/333 immune response genes and proteins are expressed in cells dispersed within all major organs of the adult purple sea urchin.

    PubMed

    Majeske, Audrey J; Oleksyk, Taras K; Smith, L Courtney

    2013-12-01

    Purple sea urchins (Strongylocentrotus purpuratus) express a highly variable set of immune genes called Sp185/333 by two subtypes of coelomocytes: the polygonal and small phagocytes. We report that the Sp185/333 genes and their encoded proteins are also expressed in all of the major organs in the adult sea urchin, including the axial organ, pharynx, esophagus, intestine and gonads. After immune challenge, there is an increase in the level of Sp185/333 mRNA in cells associated with the intestine and axial organ. The Sp185/333 proteins increase in the axial organ, pharynx, esophagus and intestine after challenge. However, the proportion of Sp185/333-positive cells only increases in the axial organ, while there is no change in that proportion in the other organs after challenge. The size range of the major Sp185/333 proteins expressed by organs is broader (5 kDa to > 250 kDa) compared with those in coelomocytes (∼40 kDa to < 250 kDa). Images of the different organs do not clarify whether coelomocytes or parenchymal cells express the Sp185/333 proteins. The increase in levels of Sp185/333 transcripts, protein expression and Sp185/333-positive cells in the axial organ in response to challenge suggests that this organ may have an important role in immunity for this species. PMID:23405032

  16. Haemato-biochemical disorders associated with nodavirus like-agent in adult leaping mullet Liza saliens (Risso, 1810) in the Caspian Sea.

    PubMed

    Ghiasi, Maryam; Binaii, Mohammad; Ghasemi, Mohdes; Fazli, Hasan; Zorriehzahra, Mohamad Jalil

    2016-03-01

    Betanoda virus is an emerging problem in several marine fish species in various geographic areas all over the world. In recent years, mullets stock of the Caspian Sea decreased dramatically and a betanoda virus like-agent was introduced as the cause of mullet's mortality. The main objective of the present study is to compare hemato-biochemical parameters in healthy and infected sharpnose mullets (Liza saliens) to betanoda virus like-agent. The adult sharpnose mullets (34 clinically affected fish + 34 apparently healthy fish) were captured from the southeast the Caspian Sea from 2012 to 2013. All of the captured fish were 4 or 5 years old. The main clinical sings of infected fish were lethargy, severe abdominal distention, abnormal swimming and hyperinflation of swim bladder. The results showed that the weight and total length of infected fish were significantly lower than the healthy fish. The results of histopatological evaluation and indirect florescent antibody test were confirmed the presence of a betanoda virus-like agent in infected fish. The diseased fish were severely anemic (hypochromic macrocytic anemia) and had a serious haemopoietic disorders. The anemia associated with a sever leukopenia, a significant rise of neutrophils and immature neutrophils and a significant decries of lymphocytes percentage. Total protein, albumin and total immunoglobulin levels were significantly reduced in the serum of infected fish, while the activities of aspartate aminotransferase and alanine aminotransferase significantly increased when compared to the healthy fish. These results suggested that the feeding of the infected fish to betanoda virus like-agent were disturbed and it could be cause haemato-biochemical disorder and mortality of the fish in Iranian water of the Caspian Sea. PMID:26925439

  17. Potential impact of climate change on the Intra-Americas Sea: Part 2. Implications for Atlantic bluefin tuna and skipjack tuna adult and larval habitats

    NASA Astrophysics Data System (ADS)

    Muhling, Barbara A.; Liu, Yanyun; Lee, Sang-Ki; Lamkin, John T.; Roffer, Mitchell A.; Muller-Karger, Frank; Walter, John F., III

    2015-08-01

    Increasing water temperatures due to climate change will likely have significant impacts on distributions and life histories of Atlantic tunas. In this study, we combined predictive habitat models with a downscaled climate model to examine potential impacts on adults and larvae of Atlantic bluefin tuna (Thunnus thynnus) and skipjack tuna (Katsuwonus pelamis) in the Intra-Americas Sea (IAS). An additional downscaled model covering the 20th century was used to compare habitat fluctuations from natural variability to predicted future changes under two climate change scenarios: Representative Concentration Pathway (RCP) 4.5 (medium-low) and RCP 8.5 (high). Results showed marked temperature-induced habitat losses for both adult and larval bluefin tuna on their northern Gulf of Mexico spawning grounds. In contrast, habitat suitability for skipjack tuna increased as temperatures warmed. Model error was highest for the two skipjack tuna models, particularly at higher temperatures. This work suggests that influences of climate change on highly migratory Atlantic tuna species are likely to be substantial, but strongly species-specific. While impacts on fish populations remain uncertain, these changes in habitat suitability will likely alter the spatial and temporal availability of species to fishing fleets, and challenge equilibrium assumptions of environmental stability, upon which fisheries management benchmarks are based.

  18. Formaldehyde reduction with scallop shell powders fired at high temperatures: Identification of the effective ingredient.

    PubMed

    Takada, Tomoya; Furusaki, Atsushi; Tanaka, Yasuaki

    2009-01-01

    The volatile organic compound (VOC) reduction activity of scallop shell powders fired at 300, 600 and 900 degrees C was examined using formaldehyde (HCHO). Raw shells as well as fired shells immediately after firing at several temperatures, except for 600 degrees C, were found to gradually remove HCHO from the air. In the case of shell powders stored for 3 months after firing, the HCHO reduction activity of the powder fired at 900 degrees C was obviously improved, with the HCHO concentrations rapidly reaching zero within 20 min. It has been found by X-ray diffraction measurements that shell powder stored for 3 months after firing at 900 degrees C contains a small amount of calcium hydroxide (Ca(OH)2) generated from calcium oxide (CaO). Our results suggest that Ca(OH)2 may be the effective ingredient in the HCHO reduction. PMID:19581713

  19. Biomarker modulation associated with marine diesel contamination in the Iceland scallop (Chlamys islandica).

    PubMed

    Milinkovitch, Thomas; Geraudie, Perrine; Camus, Lionel; Huet, Valérie; Thomas-Guyon, Hélène

    2015-12-01

    The decrease of ice cover in the Arctic will lead to an increase of ship traffic in the upcoming decades. Consequently, oil pollution is expected. In this context, the goals of this study were to evaluate the biological impact of marine diesel contamination and, on this basis, to determine analytical tools of interest (biomarkers) for future biomonitoring of diesel spills. Using a 7-day contamination protocol, this study investigated biochemical modulations in the digestive gland of the Iceland scallop (Chlamys islandica). Incorporation of contaminants was verified assessing haemolymph metabolites. Results showed a response of glutathione-S-transferase to contamination suggesting detoxification processes and the suitability of such a tool for diesel spill biomonitoring. The lack of modulation of superoxide dismutase activity and lipid peroxidation suggests no oxidative stress and the unsuitability of these molecular tools for biomonitoring. PMID:26490938

  20. Complete mitochondrial genome of the scalloped hammerhead Sphyrna lewini (Carcharhiniformes: Sphyrnidae).

    PubMed

    Chen, Xiao; Xiang, Dan; Xu, Yuziwei; Shi, Xiaofang

    2015-08-01

    The complete mitochondrial genome of the endangered scalloped hammerhead Sphyrna lewini was firstly determined in this study. It is 16,726 bp in length with the typical gene composition and orders in vertebrates. The overall base composition is 31.4% A, 26.3% C, 13.2% G and 29.1% T. Two start codon (ATG and GTG) and three stop codon (TAG, AGA and TAA/TA/T) patterns were found in protein-coding genes. Except for the tRNA-Ser2, the remaining 21 tRNAs can be folded into the typical cloverleaf structure. The control region possess the highest A + T content (66.1%) and lowest G content (12.6%) among all mitochondrial partitions. PMID:24047179

  1. Effect of increased pCO2 level on early shell development in great scallop (Pecten maximus Lamarck) larvae

    NASA Astrophysics Data System (ADS)

    Andersen, S.; Grefsrud, E. S.; Harboe, T.

    2013-10-01

    As a result of high anthropogenic CO2 emissions, the concentration of CO2 in the oceans has increased, causing a decrease in pH, known as ocean acidification (OA). Numerous studies have shown negative effects on marine invertebrates, and also that the early life stages are the most sensitive to OA. We studied the effects of OA on embryos and unfed larvae of the great scallop (Pecten maximus Lamarck), at pCO2 levels of 469 (ambient), 807, 1164, and 1599 μatm until seven days after fertilization. To our knowledge, this is the first study on OA effects on larvae of this species. A drop in pCO2 level the first 12 h was observed in the elevated pCO2 groups due to a discontinuation in water flow to avoid escape of embryos. When the flow was restarted, pCO2 level stabilized and was significantly different between all groups. OA affected both survival and shell growth negatively after seven days. Survival was reduced from 45% in the ambient group to 12% in the highest pCO2 group. Shell length and height were reduced by 8 and 15%, respectively, when pCO2 increased from ambient to 1599 μatm. Development of normal hinges was negatively affected by elevated pCO2 levels in both trochophore larvae after two days and veliger larvae after seven days. After seven days, deformities in the shell hinge were more connected to elevated pCO2 levels than deformities in the shell edge. Embryos stained with calcein showed fluorescence in the newly formed shell area, indicating calcification of the shell at the early trochophore stage between one and two days after fertilization. Our results show that P. maximus embryos and early larvae may be negatively affected by elevated pCO2 levels within the range of what is projected towards year 2250, although the initial drop in pCO2 level may have overestimated the effect of the highest pCO2 levels. Future work should focus on long-term effects on this species from hatching, throughout the larval stages, and further into the juvenile and adult

  2. Transcriptome Sequencing and Characterization of Japanese Scallop Patinopecten yessoensis from Different Shell Color Lines

    PubMed Central

    Chang, Yaqing; Zhao, Wenming; Du, Zhenlin; Hao, Zhenlin

    2015-01-01

    Shell color is an important trait that is used in breeding the Japanese scallop Patinopecten yessoensis, the most economically important scallop species in China. We constructed four transcriptome libraries from different shell color lines of P. yessoensis: the left and right shell mantles of ordinary strains of P. yessoensis and the left shell mantles of the ‘Ivory’ and ‘Maple’ strains. These four libraries were paired-end sequenced using the Illumina HiSeq 2000 platform and contained 54,802,692 sequences, 40,798,962 sequences, 74,019,262 sequences, and 44,466,166 sequences, respectively. A total of 214,087,082 expressed sequence tags were assembled into 73,522 unigenes with an average size of 1,163 bp. When the data were compared against the public Nr and Swiss-Prot databases using BlastX, nearly 30.55% (22,458) of the unigenes were significantly matched to known unique proteins. Gene Ontology annotation and pathway mapping analysis using the Kyoto Encyclopedia of Genes and Genomes categorized unigenes according to their diverse biological functions and processes and identified candidate genes that were potentially involved in growth, pigmentation, metal transcription, and immunity. Expression profile analysis was performed on all four libraries and many differentially expressed genes were identified. In addition, 5,772 simple sequence repeats were obtained from the P. yessoensis transcriptomes, and 464,197, 395,646, and 310,649 single nucleotide polymorphisms were revealed in the ordinary strains, the ‘Ivory’ strain, and the ‘Maple’ strain, respectively. These results provide valuable information for future genomic studies on P. yessoensis and improve our understanding of the molecular mechanisms involved in the growth, immunity, shell coloring, and shell biomineralization of this species. These resources also may be used in a variety of applications, such as trait mapping, marker-assisted breeding, studies of population genetics and genomics

  3. Scalloped depressions and small-sized polygons in western Utopia Planitia, Mars: A new formation hypothesis

    NASA Astrophysics Data System (ADS)

    Séjourné, A.; Costard, F.; Gargani, J.; Soare, R. J.; Fedorov, A.; Marmo, C.

    2011-04-01

    Flat-floored depressions with scalloped-shapes and spatially associated small-sized polygons (diameter <˜100 m) dot the landscape of western Utopia Planitia (centered at 45°N-95°E). The scalloped depressions are thought to be the result of ice-rich regolith undergoing degradation by sublimation or thaw. Current models suggest that the formation and development of the depressions occur in a poleward direction due to the enhanced sublimation of their equator-facing slopes. By contrast, we propose a conceptual model that shows the equatorward growth of depressions due to preferential degradation by sublimation of their pole-facing slopes. Our model is based on a geomorphological study of the depressions and small-sized polygons in western Utopia Planitia (80°-110°E, 35°-50°N), using images from the High Resolution Imaging Science Experiment (HiRISE) and topographical data from the Mars Orbiter Laser Altimeter (MOLA) and a HiRISE stereo Digital Elevation Model (DEM). Here we describe (i) a morphological evolution of small-sized polygons within the depressions, from low-centered to high-centered, that facilitates one's understanding of depression growth and development; and (ii) occurrence of v-shaped alcoves, failure cracks and semicircular hollows that point to a retrogressive degradation of the pole-facing slopes of depressions. We propose that the development of the depressions is due to heightened insolation of their pole-facing slopes, leading to enhanced sublimation of ground-ice. Based upon the inferred asymmetric insolation, we suggest that the equatorward expansion of depressions occurred during recent high-obliquity periods of Mars.

  4. Feeding and energetics of the great scallop, Pecten maximus, through a DEB model

    NASA Astrophysics Data System (ADS)

    Lavaud, Romain; Flye-Sainte-Marie, Jonathan; Jean, Fred; Emmery, Antoine; Strand, Øivind; Kooijman, Sebastiaan A. L. M.

    2014-11-01

    We developed a full life-cycle bioenergetic model for the great scallop Pecten maximus relying on the concepts of the Dynamic Energy Budget (DEB) theory. The covariation method was implemented to estimate the parameters of a standard DEB model. Such models are able to predict various metabolic processes from a food availability marker and temperature in the environment. However, suspension-feeders are likely to feed on various trophic sources, from microalgae cells to detritus. They are also able to sort and select food particles very efficiently, depending on their size, energetic value or quality. The present model includes a mechanistic description of the feeding processes, based on Kooijman's Synthesizing Unit principle which allows to deal with several food sources. Moreover we tested the hypothesis of a differential selectivity between two potential substrates (phytoplankton cell and the remaining particulate organic matter). Simulations of shell length, daily shell growth rate, dry weight and gonado-somatic index (GSI) variations were realized and compared to field data from a monitoring conducted in the Bay of Brest (Brittany, France) for six years. The model shows its capacity to efficiently reproduce all life history traits of the wild great scallops. Predicted length data were estimated to the nearest millimeter. The fit of simulated weights to observed data was very satisfactory. GSI predictions were also in accordance with observations but improvements are required to better capture the sharp increase of gametogenesis at the beginning of the year. Finally, results bring evidences that P. maximus is actually preferentially feed on living algae cells rather than on the rest of organic particles.

  5. The Origin and Age of Scallop Floodplain Benches from Difficult Run, Fairfax County, Virginia.

    NASA Astrophysics Data System (ADS)

    Scamardo, J. E.; Pizzuto, J. E.; Skalak, K.; Benthem, A.

    2015-12-01

    Sediment is deposited within scallop-shaped erosional scarps that form between trees armoring the banks of Difficult Run, a suburban watershed with a forested riparian zone. These deposits create small (surface area 85 m2, volume 300 m3), low-lying floodplain landforms this group terms Scallop Floodplain Benches (SFB). It is hypothesized that SFB formed within the past couple decades initially forming as transversal accretion deposits and eventually gaining floodplain features dominated by vertical accretion. Stratigraphic data supports that SFB deposits begin laterally as sand and gravel bars approximately 100 cm thick, and continue to grow by vertical accretion of sand, silt, and clay. As a SFB reaches its maximum height, a distinctive levee develops adjacent to the channel, and fine-grained silt and clay are deposited behind the levee. Core samples to a depth of 118 cm and additional samples from an overbank event that occurred on June 20, 2015 were collected from one of two SFB on Difficult Run near Leesburg Pike. The grain size distribution was measured using a Coulter Counter and activities of Pb-210, Cs-137, and Be-7 were measured using High Purity Germanium Detectors. Cs-137 activities are relatively constant with depth without a well-defined peak, suggesting that the SFB was deposited after 1963. Be-7 is present in the recent flood deposits, but is absent below the surface, suggesting that the SFB deposits are at least several years old. Excess Pb-210 activities decrease exponentially with depth, and can be fit using the Constant Rate of Supply method to determine an average age of approximately 13.5 years for the SFB. The SFB is storing sediment at a rate of 27 tons/year, which is equal to 0.35% of the annual sediment load of Difficult Run, based on this average age. SFB appear to be a significant component of the sediment storage of Difficult Run and therefore should be considered in the sediment budget.

  6. Fertilization and Cytogenetic Examination of Interspecific Reciprocal Hybridization between the Scallops, Chlamys farreri and Mimachlamys nobilis

    PubMed Central

    Huang, Xiaoting; Bi, Ke; Hu, Liping; Sun, Yan; Lu, Wei; Bao, Zhenmin

    2011-01-01

    Crossbreeding is a powerful tool for improving productivity and profitability in aquaculture. We conducted a pilot study of an artificial cross between two important cultivated scallops in China, Chlamys farreri and Mimachlamys nobilis, to test the feasibility of interspecific hybridization. Reciprocal hybridization experiments were performed using a single-pair mating strategy (M. nobilis ♀ × C. farreri ♂ and C. farreri ♀ × M. nobilis ♂). The fertilization of each pair was tracked using fluorescence staining of the gametes, and the chromosomes of the F1 hybrid larvae were examined via conventional karyotyping and genomic in situ hybridization (GISH). We observed moderate fertilization success in both interspecific crosses, although the overall fertilization was generally less rapid than that of intraspecific crosses. Conventional karyotyping showed that 70.4% of the viable F1 larvae in M. nobilis ♀ × C. farreri ♂ and 55.4% in C. farreri ♀ × M. nobilis ♂ comprised hybrid karyotypes (2n = 35 = 6m+5sm+11st+13t), and the results were further confirmed by GISH. Interestingly, we detected a few F1 from the M. nobilis ♀ × C. farreri ♂ cross that appeared to have developed gynogenetically. In addition, chromosome fragmentations, aneuploids and allopolyploids were observed in some F1 individuals. Our study presents evidence that the artificial cross between M. nobilis and C. farreri is experimentally possible. Further investigations of the potential heterosis of the viable F1 offspring at various developmental stages should be conducted to obtain a comprehensive evaluation of the feasibility of crossbreeding between these two scallop species. PMID:22110617

  7. Microsatellite-centromere mapping in Japanese scallop ( Patinopecten yessoensis) through half-tetrad analysis in gynogenetic diploid families

    NASA Astrophysics Data System (ADS)

    Li, Qi; Qi, Mingjun; Nie, Hongtao; Kong, Lingfeng; Yu, Hong

    2016-06-01

    Gene-centromere mapping is an essential prerequisite for understanding the composition and structure of genomes. Half-tetrad analysis is a powerful tool for mapping genes and understanding chromosomal behavior during meiosis. The Japanese scallop ( Patinopecten yessoensis), a cold-tolerant species inhabiting the northwestern Pacific coast, is a commercially important marine bivalve in Asian countries. In this study, inheritance of 32 informative microsatellite loci was examined in 70-h D-shaped larvae of three induced meiogynogenetic diploid families of P. yessoensis for centromere mapping using half-tetrad analysis. The ratio of gynogenetic diploids was proven to be 100%, 100% and 96% in the three families, respectively. Inheritance analysis in the control crosses showed that 51 of the 53 genotypic ratios observed were in accordance with Mendelian expectations at the 5% level after Bonferroni correction. Seven of the 32 microsatellite loci showed the existence of null alleles in control crosses. The second division segregation frequency ( y) of the microsatellite loci ranged from 0.07 to 0.85 with a mean of 0.38, suggesting the existence of positive interference after a single chiasma formation in some chromosomes in the scallop. Microsatellite-centromere distances ranged from 4 cM to 42 cM under the assumption of complete interference. Information on the positions of centromeres in relation to the microsatellite loci will represent a contribution towards the assembly of genetic maps in the commercially important scallop species.

  8. A simple method to reduce the risk of cadmium exposure from consumption of Iceland scallops (Chlamys islandica) fished in Greenland.

    PubMed

    Bach, Lis; Sonne, Christian; Rigét, Frank F; Dietz, Rune; Asmund, Gert

    2014-08-01

    This paper studied the levels and organ distribution of the toxic heavy metal cadmium in scallops from unpolluted Greenlandic waters. The scallops had an average cadmium concentration of 2.93 ± 0.94 μg/g wet weight in the total soft tissues and no concentration dependent effect was found for gender or size (both p>0.05). The kidney was the primary organ for cadmium accumulation with a mean of 226.2 ± 111.7 μg/g wet weight, and despite the small weight of the kidney, it appeared as the principal contributor of cadmium with 92% of the total cadmium body burden. The cadmium concentrations in the total soft tissues far exceeded the EU-limit of 1 μg/g wet weight for cadmium in bivalves. Based on this, selective evisceration of the cadmium-rich kidney and digestive gland during processing can be regarded as a reliable measure to be taken in order to reduce the cadmium content of scallops used for human consumption. PMID:24815343

  9. The phylogeny of native and exotic scallops cultured in China based on 16S rDNA sequences

    NASA Astrophysics Data System (ADS)

    Liu, Baozhong; Dong, Bo; Xiang, Jianhai; Wang, Zaizhao

    2007-01-01

    Scallops of the Family Pectinidae are a valuable resource in marine industry of the world. Understanding the phylogeny of the family is important for the development of the industry. In this study, partial 16S mitochondrial rDNA genes were obtained from 8 scallop species that are commonly cultured indigenous and transplanted species in China. Phylogenetic relationships of Pectinidae were analyzed based on the 8 sequences and other 5 published ones in GenBank, representing 9 genera of the family. The molecular phylogeny trees were constructed using 3 methods with software PHYLIP. The results showe that total 13 species of scallops clustered in 4 clades. Pecten maximus joins P. jacobaeus then Amusium pleuronectes in cluster, indicating close relationship of genus Amusium with Pecten in evolution. P. yessoensis is close to Chlamys farreri and C. islandica. No enough material was available to single out genus Patinopecten as an independent monophyletic subfamily. The position of Adamussium colbecki indicates that it is far from genus Pecten but near to genus Chlamys in evolution.

  10. Interactive effects of near-future temperature increase and ocean acidification on physiology and gonad development in adult Pacific sea urchin, Echinometra sp . A

    NASA Astrophysics Data System (ADS)

    Uthicke, S.; Liddy, M.; Nguyen, H. D.; Byrne, M.

    2014-09-01

    Increased atmospheric CO2 will have a twofold impact on future marine ecosystems, increasing global sea surface temperatures and uptake of CO2 (Ocean Acidification). Many experiments focus on the investigation of one of these stressors, but under realistic future climate predictions, these stressors may have interactive effects on individuals. Here, we investigate the effect of warming and acidification in combination. We test for interactive effects of potential near-future (2100) temperature (+2 to 3 °C) and pCO2 (~860-940 μAtm) levels on the physiology of the tropical echinoid Echinometra sp . A. The greatest reduction in growth was under simultaneous temperature and pH/ pCO2 stress (marginally significant temperature × pH/ pCO2 interaction). This was mirrored by the physiological data, with highest metabolic activity (measured as respiration and ammonium excretion) occurring at the increased temperature and pCO2 treatment, although this was not significant for excretion. The perivisceral coelomic fluid pH was ~7.5-7.6, as typical for echinoids, and showed no significant changes between treatments. Indicative of active calcification, internal magnesium and calcium concentrations were reduced compared to the external medium, but were not different between treatments. Gonad weight was lower at the higher temperature, and this difference was more distinct and statistically significant for males. The condition of the gonads assessed by histology declined in increased temperature and low pH treatments. The Echinometra grew in all treatments indicating active calcification of their magnesium calcite tests even as carbonate mineral saturation decreased. Our results indicate that the interactive temperature and pH effects are more important for adult echinoids than individual stressors. Although adult specimens grow and survive in near-future conditions, higher energy demands may influence gonad development and thus population maintenance.

  11. A small-scale comparison of Iceland scallop size distributions obtained from a camera based autonomous underwater vehicle and dredge survey.

    PubMed

    Singh, Warsha; Örnólfsdóttir, Erla B; Stefansson, Gunnar

    2014-01-01

    An approach is developed to estimate size of Iceland scallop shells from AUV photos. A small-scale camera based AUV survey of Iceland scallops was conducted at a defined site off West Iceland. Prior to height estimation of the identified shells, the distortions introduced by the vehicle orientation and the camera lens were corrected. The average AUV pitch and roll was 1.3 and 2.3 deg that resulted in <2% error in ground distance rendering these effects negligible. A quadratic polynomial model was identified for lens distortion correction. This model successfully predicted a theoretical grid from a frame photographed underwater, representing the inherent lens distortion. The predicted shell heights were scaled for the distance from the bottom at which the photos were taken. This approach was validated by height estimation of scallops of known sizes. An underestimation of approximately 0.5 cm was seen, which could be attributed to pixel error, where each pixel represented 0.24 x 0.27 cm. After correcting for this difference the estimated heights ranged from 3.8-9.3 cm. A comparison of the height-distribution from a small-scale dredge survey carried out in the vicinity showed non-overlapping peaks in size distribution, with scallops of a broader size range visible in the AUV survey. Further investigations are necessary to evaluate any underlying bias and to validate how representative these surveys are of the true population. The low resolution images made identification of smaller scallops difficult. Overall, the observations of very few small scallops in both surveys could be attributed to low recruitment levels in the recent years due to the known scallop parasite outbreak in the region. PMID:25303243

  12. A Small-Scale Comparison of Iceland Scallop Size Distributions Obtained from a Camera Based Autonomous Underwater Vehicle and Dredge Survey

    PubMed Central

    Singh, Warsha; Örnólfsdóttir, Erla B.; Stefansson, Gunnar

    2014-01-01

    An approach is developed to estimate size of Iceland scallop shells from AUV photos. A small-scale camera based AUV survey of Iceland scallops was conducted at a defined site off West Iceland. Prior to height estimation of the identified shells, the distortions introduced by the vehicle orientation and the camera lens were corrected. The average AUV pitch and roll was and deg that resulted in error in ground distance rendering these effects negligible. A quadratic polynomial model was identified for lens distortion correction. This model successfully predicted a theoretical grid from a frame photographed underwater, representing the inherent lens distortion. The predicted shell heights were scaled for the distance from the bottom at which the photos were taken. This approach was validated by height estimation of scallops of known sizes. An underestimation of approximately cm was seen, which could be attributed to pixel error, where each pixel represented cm. After correcting for this difference the estimated heights ranged from cm. A comparison of the height-distribution from a small-scale dredge survey carried out in the vicinity showed non-overlapping peaks in size distribution, with scallops of a broader size range visible in the AUV survey. Further investigations are necessary to evaluate any underlying bias and to validate how representative these surveys are of the true population. The low resolution images made identification of smaller scallops difficult. Overall, the observations of very few small scallops in both surveys could be attributed to low recruitment levels in the recent years due to the known scallop parasite outbreak in the region. PMID:25303243

  13. Molecular evidence for the existence of an aryl hydrocarbon receptor pathway in scallops Chlamys farreri.

    PubMed

    Cai, Yuefeng; Pan, Luqing; Miao, Jingjing

    2016-01-01

    The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that controls the expression of a diverse set of genes. In this study we cloned full-length cDNAs encoding an AhR homologue (designated CfAhR, Accession number: FJ588640) from scallop Chlamys farreri. The CfAhR sequence was constituted by an open reading frame (ORF) of 2466bp encoding 821 amino acids. The predicted molecular weight was 93.0kDa. The CfAhR showed a high conservation of the residues and domains essential to the function of AhR, including basic helix-loop-helix (bHLH) and Per-ARNT-Sim (PAS) domains. Phylogenetic analysis demonstrated that it was clustered within the invertebrate AhR branch. CfAhR expression was detected in gill, digestive gland, ovary, spermary, mantle and adductor, and the highest transcription level was observed in gill. Recombinant plasmid CfAhR-pET32a (designated rCfAhR) was successfully expressed in Escherichia coli BL21. To investigate the molecular detoxification mechanism of benzo(a)pyrene (BaP) detoxification-related genes (AhR; aryl hydrocarbon receptor nuclear translocator, ARNT; heat shock protein 90, HSP90; cytochrome P450 1A1, CYP1A1; glutathione S-transferase pi, GST-pi and P glycoprotein, Pgp) in C. farreri gill, real-time quantitative PCR analysis revealed that the mRNA expression level of CfAhR, xenobiotic-metabolizing enzymes and efflux transporters was induced by BaP and was sensitive to BaP exposure time and concentration, suggesting that BaP influenced the expression of a putative AhR/ARNT signaling pathway in scallops. Our results support the possibility that CfAhR genes are early molecular indicators of BaP through a putative CYP signaling pathway in marine bivalves. PMID:26927881

  14. DNA-methylation dependent regulation of embryo-specific 5S ribosomal DNA cluster transcription in adult tissues of sea urchin Paracentrotus lividus.

    PubMed

    Bellavia, Daniele; Dimarco, Eufrosina; Naselli, Flores; Caradonna, Fabio

    2013-10-01

    We have previously reported a molecular and cytogenetic characterization of three different 5S rDNA clusters in the sea urchin Paracentrotus lividus and recently, demonstrated the presence of high heterogeneity in functional 5S rRNA. In this paper, we show some important distinctive data on 5S rRNA transcription for this organism. Using single strand conformation polymorphism (SSCP) analysis, we demonstrate the existence of two classes of 5S rRNA, one which is embryo-specific and encoded by the smallest (700 bp) cluster and the other which is expressed at every stage and encoded by longer clusters (900 and 950 bp). We also demonstrate that the embryo-specific class of 5S rRNA is expressed in oocytes and embryonic stages and is silenced in adult tissue and that this phenomenon appears to be due exclusively to DNA methylation, as indicated by sensitivity to 5-azacytidine, unlike Xenopus where this mechanism is necessary but not sufficient to maintain the silenced status. PMID:23933480

  15. Genome-wide identification, characterization and expression analyses of two TNFRs in Yesso scallop (Patinopecten yessoensis) provide insight into the disparity of responses to bacterial infections and heat stress in bivalves.

    PubMed

    Xing, Qiang; Yu, Qian; Dou, Huaiqian; Wang, Jing; Li, Ruojiao; Ning, Xianhui; Wang, Ruijia; Wang, Shi; Zhang, Lingling; Hu, Xiaoli; Bao, Zhenmin

    2016-05-01

    Tumor necrosis factors receptors (TNFRs) comprise a superfamily of proteins characterized by a unique cysteine-rich domain (CRD) and play important roles in diverse physiological and pathological processes in the innate immune system, including inflammation, apoptosis, autoimmunity and organogenesis. Although significant effects of TNFRs on immunity have been reported in most vertebrates as well as some invertebrates, the complete TNFR superfamily has not been systematically characterized in scallops. In this study, two different types of TNFR-like genes, including PyTNFR1 and PyTNFR2 genes were identified from Yesso scallop (Patinopecten yessoensis, Jay, 1857) through whole-genome scanning. Phylogenetic and protein structural analyses were carried out to determine the identities and evolutionary relationships of the two genes. The expression profiling of PyTNFRs was performed at different development stages, in healthy adult tissues and in hemocytes after bacterial infection and heat stress. Expression analysis revealed that both PyTNFRs were significantly induced during the acute phase (3 h) after infection with Gram-positive (Micrococcus luteus) and Gram-negative (Vibrio anguillarum) bacteria, though much more dramatic chronic-phase (24 h) changes were observed after V. anguillarum challenge. For heat stress, only PyTNFR2 displayed significant elevation at 12 h and 24 h, which suggests a functional difference in the two PyTNFRs. Collectively, this study provides novel insight into the PyTNFRs and the specific role and response of TNFR-involved pathways in host immune responses against different bacterial pathogens and heat stress in bivalves. PMID:26988286

  16. Quantitative analyse of trace elements with HR-ICP-MS Element2 : an example of application in calcite shell of the Great Scallop Pecten Maximus.

    NASA Astrophysics Data System (ADS)

    Richard, M.; Chauvaud, L.; Benoit, M.; Thebault, J.; L'Helguen, S.; Hemond, C.; Maguer, J.; Sinquin, G.

    2008-12-01

    Carbonate minerals are abundant on the Earth's surface, and they are produced by a number of processes, including precipitation from hydrothermal fluids or synthesis by organisms like coral, foraminifera, molluscs, or bacteria. Consequently, they are found in a large variety of environments. Their isotopic compositions (Sr, C, or O ) and trace element concentrations are widely used to understand or reconstruct biological, geological or biogeochimical processes. A large scientific community define the elemental composition of bivalve shells a promising tool as a recorder of environmental parameters like sea surface temperature, salinity and primary productivity. But we have compile evidences that trace elements variation within shells can be species dependant or change in a complex network of environmental interactions. In this context, a better understanding of the incorporation of elements from seawater into biogenic carbonate is necessary to generalize the use of these proxies. Daily shell growth in the calcitic bivalve Pecten maximus has been extensively measured and these daily growth marks can be used to date each subsequent sample of calcium carbonate. In this study, micro- sampling of carbonate powder along the shell was carried out with a high-resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS, Finnigan Element2). This method led to a quantitative detection of trace element in biocaronates and to the accurate reconstruction of ontogenetic profiles of elemental ratios with a 3-day temporal resolution. Repeated analyses of different growth layers sections on the same valve showed that the trace elements are homogeneously distributed along the shell. Mo concentration was reproducible for several scallop individuals from a same location over different years and from different coastal temperate environments. Each profile was characterised by a background level punctuated by sharp episodic peaks occurring in spring (may). Some hypotheses will be

  17. Isolation, characterization, and multiplexing of novel microsatellite markers for the tropical scalloped spiny lobster (Panulirus homarus).

    PubMed

    Delghandi, M; Goddard, S; Jerry, D R; Dao, H T; Afzal, H; Al-Jardani, S S

    2015-01-01

    Of the various spiny lobster species in the tropical and subtropical Indo-West Pacific region, the tropical scalloped spiny lobster (Panulirus homarus) supports one of the most commercially valuable fishery resources in many coastal African and Asian countries. The last decade has witnessed a serious decline in the wild populations of this species. Knowledge of the genetic basis of spiny lobster population structure is a prerequisite to achieve a sustainable fisheries management for this species. Here, we describe 13 novel polymorphic microsatellite markers developed for P. homarus, using a cross-species primer design strategy based on P. ornatus Roche 454 shot-gun generated sequencing. Microsatellite polymorphisms were assessed in 96 unrelated P. homarus individuals of a natural population, with the number of alleles per locus varying from 2 to 14, the observed and expected heterozygosity from 0.00 to 0.78 and from 0.03 to 0.79, respectively, and with only four loci (Pho-G27, Pho-G32, Pho-G36, and Pho-G58) deviating from Hardy- Weinberg equilibrium. Genetic linkage disequilibrium analysis between all pairs of the loci showed significant departure from the null hypothesis between loci Pho-G22 - Pho-G30, and Pho-G30 - Pho-G35. The successful cross amplification of these microsatellites highlights the potential of the developed microsatellites for future population genetic research within the different Panulirus species. PMID:26782557

  18. Immune function in the Arctic Scallop, Chlamys islandica, following dispersed oil exposure.

    PubMed

    Hannam, Marie L; Bamber, Shaw D; Moody, John A; Galloway, Tamara S; Jones, Malcolm B

    2009-05-01

    With the current expansion of offshore oil activities in Arctic regions, there is an urgent need to establish the potential effects of oil-related compounds on Arctic organisms. As susceptibility to growth, disease and survival is determined partly by the condition of an organism's immune system, measurement of endpoints linked to the latter system provide important early warning signals of the sub-lethal effects of exposure to contaminants. This study assessed the impact of dispersed oil exposure on immune endpoints in the Arctic Scallop Chlamys islandica, using a combination of cellular and humoral biological responses. Laboratory exposures of C. islandica to sub-lethal dispersed oil concentrations (0.06 and 0.25 mg l(-1)) were conducted over 15 days, followed by a 7-day recovery period in clean, filtered seawater. Cellular endpoints were significantly altered following dispersed oil exposure: haemocyte counts (P<0.01) and protein levels (P<0.01) were significantly elevated, whilst cell membrane stability (P<0.001) and phagocytosis (P<0.01) demonstrated a significant reduction. Whilst these results indicate alteration in the immune endpoints measured, this appears to be reversible upon removal of the contaminant stress. However, the impact of long-term continuous exposure and high-level acute exposure to oil is still unknown, and may have consequences for disease resistance and hence survival. PMID:19249111

  19. Sperm nuclear expansion and meiotic maturation in normal and gynogenetic eggs of the scallop, Chlamys farreri

    NASA Astrophysics Data System (ADS)

    Pan, Ying; Li, Qi; Yu, Ruihai; Wang, Rucai

    2008-02-01

    Sperm nuclear expansion, meiosis and the association of the male and female pronuclei leading to the four-cell stage in normal Chlamys farreri eggs were observed under a fluorescence microscope. The effects of ultraviolet (UV) irradiation on the fertilizing sperm were also examined. Both normal and UV-irradiated sperm nuclei enlarged at three distinct phases (phase A, metaphase I; phase B, polar body formation; and phase C, female pronuclear development and expansion) that were temporally correlated with meiotic process of the maternal chromosomes. Sperm nuclei underwent a rapid, initial enlargement during phase A, but condensed slightly during phase B, then re-enlarged during phase C. The effects of UV irradiation were not apparent during transformation of the sperm nucleus into a male pronucleus, and there was not any apparent effect on meiotic maturation and development of the female pronucleus. However, the rate of expansion of the UV-irradiated sperm nuclei and the size of male pronuclei were reduced apparently. Unlike the female pronucleus, the male pronucleus derived from sperm genome inactivated by UV irradiation did not form chromosomes, but became a dense chromatin body (DCB). At mitotic anaphase, DCB did not participate in the karyokinesis of the first cleavage as evidenced by chromosomal nondisjunction, demonstrating the effectiveness of using UV irradiation to induce gynogenetic scallop embryos.

  20. Asymmetric hemoglobins, their thiol content, and blood glutathione of the scalloped hammerhead shark, Sphyrna lewini.

    PubMed

    Dafré, A L; Reischl, E

    1997-03-01

    Starch gel electrophoresis pH 8.6, or PAGE pH 8.9, of the scalloped hammerhead shark hemolysates showed three hemoglobins (Hb). An additional Hb between the two most mobile electrophoretic components was seen in starch gel electrophoresis, pH 8.1, and also in highly loaded PAGE gels. The relative concentration of these Hbs was variable among individuals, when accessed at pH 8.1. Dilution of hemolysates led to a redistribution of the Hb tetramer subunits. Under denaturing conditions, the unfractionated hemolysate was resolved in 3 Hb subunits. Isolated Hbs, named SL I-SL IV, showed unusual subunit compositions: SL I, the least mobile, is "b3c"; SL II is "a2bc"; SL III and SL IV are composed only by "a" subunits. Hemoglobins in the whole hemolysate have an average of two reactive cysteines per tetramer, which were not easily S-thiolated by glutathione, as is the case for related species. After hemoglobin denaturation, six additional -SH groups were titrated by Ellman's reagent. Methemoglobin content was low in the erythrocytes of nine examined specimens, 1.13 +/- 1.90%. High values for total erythrocyte glutathione (GSH) were found: 4.5 +/- 0.7 mM; n = 7. The ratio of 1.4 +/- 0.4 GSH/Hb is higher than usually reported for mammalians. PMID:9114492

  1. Morphological effect of a scallop shell on a flapping-type tidal stream generator.

    PubMed

    Le, Tuyen Quang; Ko, Jin Hwan; Byun, Doyoung

    2013-09-01

    Inspired by nature, flapping-type tidal stream generators have been introduced in recent years. The improvement in their power generation ability is known to be a critical factor in the success of these generators. So far, corrugation and camber observed in flying insects and swimming animals are known to enhance the performance of a flapping-type propulsive system. In this study, we explore the effect of corrugation and camber in a system that mimics a scallop shell in terms of its ability to extract flow energy through a two-dimensional Navier-Stokes simulation. The simulations show that the size and the activity of the leading edge vortex are strongly affected by the morphological factors of the mimicked foils, the effects of which are then advantageous in terms of the power efficiency of the flapping-type tidal stream generator. Eventually, an optimal mimicked foil, as suggested based on the morphological effects, would be a good alternative type of foil with a typical section with regard to the hydrodynamic performance and structural properties of tidal stream generators. PMID:23924846

  2. Efficacy of scallop shell powders and slaked lime for inactivating avian influenza virus under harsh conditions.

    PubMed

    Thammakarn, Chanathip; Tsujimura, Misato; Satoh, Keisuke; Hasegawa, Tomomi; Tamura, Miho; Kawamura, Akinobu; Ishida, Yuki; Suguro, Atsushi; Hakim, Hakimullah; Ruenphet, Sakchai; Takehara, Kazuaki

    2015-10-01

    The efficacy and stability of scallop shell powder (SSP) were investigated, in terms of its capacity to inactivate avian influenza virus (AIV), and compared with slaked lime (SL). An environmental simulation was conducted by emulating sunlight and wet-dry conditions. The powders were collected at consecutive 2-week intervals under sunlight and upon every resuspension. These materials were tested by mixing them with AIV and incubating the mixture for 3 min or 20 h, followed by AIV titration. At the same time, a pH buffering test was conducted by neutralization with Tris-HCl. The results revealed that SSP and SL have high alkalinity and excellent ability to inactivate AIV. In a simulated harsh environment, SSP and SL retained a satisfactory ability to inactivate AIV within 20 h throughout the experimental procedure. However, SSP was able to inactivate AIV during a short contact period (3 min), even under harsh conditions, and it was more resistant than SL to neutralization. PMID:26168709

  3. Convergent and parallel evolution in life habit of the scallops (Bivalvia: Pectinidae)

    PubMed Central

    2011-01-01

    Background We employed a phylogenetic framework to identify patterns of life habit evolution in the marine bivalve family Pectinidae. Specifically, we examined the number of independent origins of each life habit and distinguished between convergent and parallel trajectories of life habit evolution using ancestral state estimation. We also investigated whether ancestral character states influence the frequency or type of evolutionary trajectories. Results We determined that temporary attachment to substrata by byssal threads is the most likely ancestral condition for the Pectinidae, with subsequent transitions to the five remaining habit types. Nearly all transitions between life habit classes were repeated in our phylogeny and the majority of these transitions were the result of parallel evolution from byssate ancestors. Convergent evolution also occurred within the Pectinidae and produced two additional gliding clades and two recessing lineages. Furthermore, our analysis indicates that byssal attaching gave rise to significantly more of the transitions than any other life habit and that the cementing and nestling classes are only represented as evolutionary outcomes in our phylogeny, never as progenitor states. Conclusions Collectively, our results illustrate that both convergence and parallelism generated repeated life habit states in the scallops. Bias in the types of habit transitions observed may indicate constraints due to physical or ontogenetic limitations of particular phenotypes. PMID:21672233

  4. Expression pattern of phb2 and its potential function in spermatogenesis of scallop ( Chlamys farreri)

    NASA Astrophysics Data System (ADS)

    Han, Tiantian; Ma, Xiaoshi; Liang, Shaoshuai; Gao, Beibei; Zhang, Zhifeng

    2015-12-01

    Prohibitin (PHB) participates in several biological processes including apoptosis, transcription regulation and suppression of cell proliferation in mammals. In this study, we cloned the full-length cDNA of prohibitin 2 ( Cf-phb2) from the testis of scallop ( Chlamys farreri). The deduced amino acid sequence presented a characteristic of PHB family with the PHB domain, and clustered with PHB2 of other species. Temporal and spatial expression of Cf-phb2 in testis during the reproductive cycle was detected by quantitative real-time PCR (qRT-PCR) and in situ hybridization. The expression of Cf-phb2 in the testis increased when testis developed from the resting stage to mature stage. The mRNA abundance of Cf-phb2 was the highest at mature stage, which was about 15-fold higher than that at proliferative stage. The expression of Cf-phb2 could be detected by in situ hybridization in all types of germ cells in testis, including spermatogonia, spermatocytes, spermatids and spermatozoa. The intensity of the signal increased with the spermatogenesis and was the highest in spermatids, which suggested that CF-PHB2 might affect the spermatogenesis of C. farreri.

  5. The cDNA cloning and mRNA expression of a potential selenium-binding protein gene in the scallop Chlamys farreri.

    PubMed

    Song, Linsheng; Zou, Huibin; Chang, Yaqing; Xu, Wei; Wu, Longtao

    2006-01-01

    Selenium binding proteins (SeBP) represent a family of proteins that are believed to be involved in controlling the oxidation/reduction in many physiological processes. The cDNA of Zhikong Scallop Chlamys farreri selenium binding protein (zSeBP) was cloned by expressed sequence tag (EST) and RACE techniques. The high similarity of zSeBP deduced amino acid sequence with the SeBP in other organisms, such as bird, fish, frog, mosquito, fruit fly, mammalian, and even nematode and microorganism indicated that zSeBP should be a member of SeBP family. The temporal expression of zSeBP in the hemocytes was measured by semi-quantitative RT-PCR after scallops were stimulated by either oxidative stress or microbial challenge. The expression of zSeBP was up-regulated progressively after stimulation, and then dropped gradually to the original level. Meanwhile, malondialdehyde (MDA) measured by the colorimetric method in the microbial challenged scallops increased immediately after scallops was challenged by microbes, and was significantly higher than that in the control scallops. Results indicated that the microbial infection could incense the disorder of oxidation/reduction and may result in high MDA production. The negative correlation between the expression level of zSeBP and the MDA content suggested that zSeBP could play an important role in mediating the anti-oxidation mechanisms and immune response in marine invertebrates. PMID:15975653

  6. Differential immune response of vitellogenin gene to Vibrio anguillarum in noble scallop Chlamys nobilis and its correlation with total carotenoid content.

    PubMed

    Zhang, Qian; Lu, Yeqing; Zheng, Huaiping; Liu, Helu; Li, Shengkang

    2016-03-01

    Vitellogenin (Vg), an egg yolk precursor protein, not only functions as a source of nutrients and a nonpolar molecular carrier that combine and transfer lipids, proteins, vitamin and carotenoids to oocytes during the oogenesis. but also links with the immune defense in many oviparous animals. To investigate whether Vg plays a immune defensive role in noble scallop Chlamys nobilis, an acute Vibrio anguillarum infection experiment was conducted in orange and brown scallops with different carotenoids content. qRT-PCR result showed that Vg transcripts were significantly up-regulated after challenge with V. anguillarum in orange and brown shell scallops compared to the control group and Vg expression reached the highest spot at 6 h, indicated that Vg possessed an immune function in the noble scallop. Interestingly, a significantly positive correlation between Vg transcript levels and total carotenoids content in the ovary was observed, indicating that Vg gene expression was up regulated by carotenoids. The results suggest that Vg is a potent immune protector and carotenoid may linked with Vg plays an important role in host immune system against pathogens in noble scallop C. nobilis. PMID:26767747

  7. Short-Term Behavioural Responses of the Great Scallop Pecten maximus Exposed to the Toxic Alga Alexandrium minutum Measured by Accelerometry and Passive Acoustics

    PubMed Central

    Coquereau, Laura; Jolivet, Aurélie; Hégaret, Hélène; Chauvaud, Laurent

    2016-01-01

    Harmful algal blooms produced by toxic dinoflagellates have increased worldwide, impacting human health, the environment, and fisheries. Due to their potential sensitivity (e.g., environmental changes), bivalves through their valve movements can be monitored to detect harmful algal blooms. Methods that measure valve activity require bivalve-attached sensors and usually connected cables to data transfers, leading to stress animals and limit the use to sessile species. As a non-intrusive and continuously deployable tool, passive acoustics could be an effective approach to detecting harmful algal blooms in real time based on animal sound production. This study aimed to detect reaction changes in the valve movements of adult Pecten maximus exposed to the toxic dinoflagellate Alexandrium minutum using both accelerometry and passive acoustic methods. Scallops were experimentally exposed to three ecologically relevant concentrations of A. minutum for 2 hours. The number of each type of valve movement and their sound intensity, opening duration, and valve-opening amplitude were measured. Four behaviours were identified: closures, expulsion, displacement, and swimming. The response of P. maximus to A. minutum occurred rapidly at a high concentration. The valve activity of P. maximus was different when exposed to high concentrations (500 000 cells L-1) of A. minutum compared to the non-toxic dinoflagellate Heterocapsa triquetra; the number of valve movements increased, especially closure and expulsion, which were detected acoustically. Thus, this study demonstrates the potential for acoustics and sound production changes in the detection of harmful algal blooms. However, field trials and longer duration experiments are required to provide further evidence for the use of acoustics as a monitoring tool in the natural environment where several factors may interfere with valve behaviours. PMID:27508498

  8. A custom-made scalloped stentgraft to preserve left subclavian artery flow in descending thoracic aortic disease with a short neck.

    PubMed

    Van Der Weijde, Emma; Bakker, Olaf J; Heijmen, Robin H

    2016-05-01

    In thoracic stentgrafting, a short proximal landing zone may necessitate intentional occlusion of the left subclavian artery, which may lead to brain, spinal cord, and left arm malperfusion. A scalloped stentgraft is designed for adequate proximal sealing and preserving the left subclavian artery flow. We performed a systematic review, describe the required pre-operative planning and details of the perioperative technique used and report our own experience. In literature, only 29 patients were reported so far using a proximal scalloped stentgraft. Results show a high technical success rate and low complication rate. These results are comparable to the results from our own institution. From these first small series the scalloped thoracic endovascular aortic repair appears to be a safe and relatively simple solution for thoracic aortic disease involving the left subclavian artery. PMID:27018248

  9. The Polymorphism in the Promoter of HSP70 Gene Is Associated with Heat Tolerance of Two Congener Endemic Bay Scallops (Argopecten irradians irradians and A. i. concentricus)

    PubMed Central

    Yang, Chuanyan; Wang, Lingling; Wang, Jingjing; Jiang, Qiufen; Qiu, Limei; Zhang, Huan; Song, Linsheng

    2014-01-01

    Background The heat shock protein 70 (HSP70) is one kind of molecular chaperones, which plays a key role in protein metabolism under normal and stress conditions. Methodology In the present study, the mRNA expressions of HSP70 under normal physiological condition and after acute heat stress were investigated in gills of two bay scallop populations (Argopecten irradians irradians and A. i. concentricus). The heat resistant scallops A. i. concentricus showed significantly lower basal level and higher induction of HSP70 compared with that of the heat sensitive scallops A. i. irradians. The promoter sequence of HSP70 gene from bay scallop (AiHSP70) was cloned and the polymorphisms within this region were investigated to analyze their association with heat tolerance. Totally 11 single nucleotide polymorphisms (SNPs) were identified, and four of them (−967, −480, −408 and −83) were associated with heat tolerance after HWE analysis and association analysis. Based on the result of linkage disequilibrium analysis, the in vitro transcriptional activities of AiHSP70 promoters with different genotype were further determined, and the results showed that promoter from A. i. concentricus exhibited higher transcriptional activity than that from A. i. irradians (P<0.05). Conclusions The results provided insights into the molecular mechanisms underlying the thermal adaptation of different congener endemic bay scallops, which suggested that the increased heat tolerance of A. i. concentricus (compared with A. i. irradians) was associated with the higher expression of AiHSP70. Meanwhile, the −967 GG, −480 AA, −408 TT and −83 AG genotypes could be potential markers for scallop selection breeding with higher heat tolerance. PMID:25028964

  10. Characterization of the mantle transcriptome of yesso scallop (Patinopecten yessoensis): identification of genes potentially involved in biomineralization and pigmentation.

    PubMed

    Sun, Xiujun; Yang, Aiguo; Wu, Biao; Zhou, Liqing; Liu, Zhihong

    2015-01-01

    The Yesso scallop Patinopecten yessoensis is an economically important marine bivalve species in aquaculture and fishery in Asian countries. However, limited genomic resources are available for this scallop, which hampers investigations into molecular mechanisms underlying their unique biological characteristics, such as shell formation and pigmentation. Mantle is the special tissue of P. yessoensis that secretes biomineralization proteins inducing shell deposition as well as pigmentation on the shells. However, a current deficiency of transcriptome information limits insight into mechanisms of shell formation and pigmentation in this species. In this study, the transcriptome of the mantle of P. yessoensis was deeply sequenced and characterized using Illumina RNA-seq technology. A total of 86,521 unique transcripts are assembled from 55,884,122 reads that passed quality filters, and annotated, using Gene Ontology classification. A total of 259 pathways are identified in the mantle transcriptome, including the calcium signaling and melanogenesis pathways. A total of 237 unigenes that are homologous to 102 reported biomineralization genes are identified, and 121 unigenes that are homologous to 93 known proteins related to melanin biosynthesis are found. Twenty-three annotated unigenes, which are mainly homologous to calmodulin and related proteins, Ca2+/calmodulin-dependent protein kinase, adenylate/guanylate cyclase, and tyrosinase family are potentially involved in both biomineralization and melanin biosynthesis. It is suggested that these genes are probably not limited in function to induce shell deposition by calcium metabolism, but may also be involved in pigmentation of the shells of the scallop. This potentially supports the idea that there might be a link between calcium metabolism and melanin biosynthesis, which was previously found in vertebrates. The findings presented here will notably advance the understanding of the sophisticated processes of shell

  11. Characterization of the Mantle Transcriptome of Yesso Scallop (Patinopecten yessoensis): Identification of Genes Potentially Involved in Biomineralization and Pigmentation

    PubMed Central

    Sun, Xiujun; Yang, Aiguo; Wu, Biao; Zhou, Liqing; Liu, Zhihong

    2015-01-01

    The Yesso scallop Patinopecten yessoensis is an economically important marine bivalve species in aquaculture and fishery in Asian countries. However, limited genomic resources are available for this scallop, which hampers investigations into molecular mechanisms underlying their unique biological characteristics, such as shell formation and pigmentation. Mantle is the special tissue of P. yessoensis that secretes biomineralization proteins inducing shell deposition as well as pigmentation on the shells. However, a current deficiency of transcriptome information limits insight into mechanisms of shell formation and pigmentation in this species. In this study, the transcriptome of the mantle of P. yessoensis was deeply sequenced and characterized using Illumina RNA-seq technology. A total of 86,521 unique transcripts are assembled from 55,884,122 reads that passed quality filters, and annotated, using Gene Ontology classification. A total of 259 pathways are identified in the mantle transcriptome, including the calcium signaling and melanogenesis pathways. A total of 237 unigenes that are homologous to 102 reported biomineralization genes are identified, and 121 unigenes that are homologous to 93 known proteins related to melanin biosynthesis are found. Twenty-three annotated unigenes, which are mainly homologous to calmodulin and related proteins, Ca2+/calmodulin-dependent protein kinase, adenylate/guanylate cyclase, and tyrosinase family are potentially involved in both biomineralization and melanin biosynthesis. It is suggested that these genes are probably not limited in function to induce shell deposition by calcium metabolism, but may also be involved in pigmentation of the shells of the scallop. This potentially supports the idea that there might be a link between calcium metabolism and melanin biosynthesis, which was previously found in vertebrates. The findings presented here will notably advance the understanding of the sophisticated processes of shell

  12. Reconstruction of seasonal temperature variability in the tropical Pacific Ocean from the shell of the scallop, Comptopallium radula

    NASA Astrophysics Data System (ADS)

    Thébault, Julien; Chauvaud, Laurent; Clavier, Jacques; Guarini, Jennifer; Dunbar, Robert B.; Fichez, Renaud; Mucciarone, David A.; Morize, Eric

    2007-02-01

    We investigated the oxygen isotope composition (δ 18O) of shell striae from juvenile Comptopallium radula (Mollusca; Pectinidae) specimens collected live in New Caledonia. Bottom-water temperature and salinity were monitored in-situ throughout the study period. External shell striae form with a 2-day periodicity in this scallop, making it possible to estimate the date of precipitation for each calcite sample collected along a growth transect. The oxygen isotope composition of shell calcite (δ 18O shell calcite) measured at almost weekly resolution on calcite accreted between August 2002 and July 2003 accurately tracks bottom-water temperatures. A new empirical paleotemperature equation for this scallop species relates temperature and δ 18O shell calcite: t(°C)=20.00(±0.61)-3.66(±0.39)×(δ18O-δ18O) The mean absolute accuracy of temperature estimated using this equation is 1.0 °C at temperatures between 20 and 30 °C. Uncertainties regarding the precise timing of CaCO 3 deposition and the actual variations in δ 18O water at our study sites probably contribute to this error. Comparison with a previously published empirical paleotemperature equation indicates that C. radula calcite is enriched in 18O by ˜0.7‰ relative to equilibrium. Given the direction of this offset and the lack of correlation between shell growth rate and δ 18O shell calcite, this disequilibrium is unlikely to be related to kinetic isotope effects. We suggest that this enrichment reflects (1) a relatively low pH in the scallop's marginal extrapallial fluid (EPF), (2) an isotopic signature of the EPF different from that of seawater, or (3) Rayleigh fractionation during the biocalcification process. Relative changes in δ 18O shell calcite reflect seawater temperature variability at this location and we suggest that the shell of C. radula may be useful as an archive of past seawater temperatures.

  13. Satellite Studies of Interactions Between Antarctic Circumpolar Current Eddies and Sea Ice

    NASA Astrophysics Data System (ADS)

    Springer, S. R.; Padman, L.; Dinniman, M. S.

    2015-12-01

    Wintertime sea ice extent around Antarctica has shown a positive trend during at least the past decade. The maximum northward expansion of sea ice is likely to be limited by the strong ocean temperature gradients associated with fronts of the Antarctic Circumpolar Current (ACC). The ACC is, however, very dynamically unstable, with mesoscale eddies accounting for a large fraction of the variance in surface currents and sea surface temperature (SST). We combine satellite-observed sea-ice concentration, SST, and geostrophic eddy velocities to explore the hypothesis that dynamic and thermodynamic interactions between mesoscale eddies and sea ice exert an additional influence on the location of the winter sea ice margin. Advancing sea ice develops meridional deviations at horizontal scales of ~100 km, lengthening the perimeter of the ice-covered area by 30-70%. In many cases, this "scalloping" of the ice margin can be attributed to advection by eddy velocities. The effect varies regionally, depending on the proximity of the ice edge to the ACC. From the Amundsen Sea eastward through the Drake Passage the southern limit of eddy variability coincides with the northernmost extent of sea ice, and scalloping is common. By deforming the ice margin, eddies increase the potential for ice-edge melting and destruction by Southern Ocean surface wave action, while eddy-driven ice advection modifies the mean thermodynamic exchanges responsible for mass loss from the base of the ice pack. We use observations and models to estimate sea-ice loss caused by eddy/ice interactions.

  14. Characterization and functional analysis of two inhibitor of apoptosis genes in Zhikong scallop Chlamys farreri.

    PubMed

    Miao, Guoying; Qi, Haigang; Li, Li; Que, Huayong; Zhang, Guofan

    2016-07-01

    The proteins of inhibitor of apoptosis (IAP) family play important roles in regulation of apoptosis, immunological response and cell proliferation. Here we reported two IAP genes (named CfIAP1 and CfIAP2) in Zhikong scallop Chlamys farreri. The full-length CfIAP1 cDNA contained 1552 nucleotides, encoding a predicted protein of 251 amino acids with two BIR domains. The full-length CfIAP2 cDNA contained 1243 nt, encoding a 356-aa protein with one BIR domain and one RING domain. The two genes are ubiquitously expressed in six types of tissue of C. farreri. The expression levels of CfIAP1 and CfIAP2 were significantly up-regulated after challenged with acute viral necrobiotic disease virus, lipopolysaccharide and exposure to air. Subcellular localization assay showed that CfIAP1 was mainly distributed in cytoplasm and CfIAP2 was in cytoplasm and nucleus. As assessed using a kit designed to test Caspase3 function in mammalian cells, the activity of CfCaspase3 was enhanced as a result of the down-regulation of CfIAP2 expression by dsRNA-mediated gene silencing. Our study indicated that CfIAP1 and CfIAP2 may participate in the innate immunity and stress responses and that CfIAP2 might block apoptosis via inhibiting CfCaspase3 indirectly through an unexplored mechanism in C. farreri. PMID:26875631

  15. Characterization of the Zhikong scallop (Chlamys farreri) mantle transcriptome and identification of biomineralization-related genes.

    PubMed

    Shi, Mingjun; Lin, Ya; Xu, Guangrui; Xie, Liping; Hu, Xiaoli; Bao, Zhenmin; Zhang, Rongqing

    2013-12-01

    Chlamys farreri is a significant species in aquaculture and fishery in East Asia. A deep understanding of its shell formation by studying the transcriptome of the mantle, a key organ in shell formation, could provide important guidance for its culture. Thus, we sequenced and analyzed the mantle transcriptome of C. farreri. The 77,975 unigenes were generated after Illumina sequencing and de novo assembly. The unigenes were annotated using authoritative databases (non-redundant (NR), COG, Gene Ontology (GO), and KEGG) to obtain functional information. BLASTX alignment was performed between unigenes and reported proteins related to biomineralization. The results identified 53 homologous genes representing 17 matrix proteins, most of which are involved in calcite formation, and 171 homologies with 26 proteins related to general processes of biomineralization. The discovery and unusually high expression of MSP-1 suggested its importance in scallops. Homologous unigenes with aragonite-formation-related matrix proteins were much fewer compared with those related to calcite formation. The results implied that, in C. farreri, the number and proportion of matrix proteins related to aragonite formation is much lower than those related to calcite formation, which was consistent with the proportions of aragonite and calcite in C. farreri shells. Thus, the formation of different polymorphs of calcium carbonate (calcite and aragonite) in molluskan shells is regulated by different groups of proteins. Moreover, 17 candidate unigenes, which are probably involved in biomineralization, were predicted by screening for gene products with secreted domains and tandem-arranged repeat units. Our results contribute to the understanding of biomineralization processes and the evolution of shell formation. PMID:23860577

  16. Molecular cloning and characterization of SoxB2 gene from Zhikong scallop Chlamys farreri

    NASA Astrophysics Data System (ADS)

    He, Yan; Bao, Zhenmin; Guo, Huihui; Zhang, Yueyue; Zhang, Lingling; Wang, Shi; Hu, Jingjie; Hu, Xiaoli

    2013-11-01

    The Sox proteins play critical roles during the development of animals, including sex determination and central nervous system development. In this study, the SoxB2 gene was cloned from a mollusk, the Zhikong scallop ( Chlamys farreri), and characterized with respect to phylogeny and tissue distribution. The full-length cDNA and genomic DNA sequences of C. farreri SoxB2 ( Cf SoxB2) were obtained by rapid amplification of cDNA ends and genome walking, respectively, using a partial cDNA fragment from the highly conserved DNA-binding domain, i.e., the High Mobility Group (HMG) box. The full-length cDNA sequence of Cf SoxB2 was 2 048 bp and encoded 268 amino acids protein. The genomic sequence was 5 551 bp in length with only one exon. Several conserved elements, such as the TATA-box, GC-box, CAAT-box, GATA-box, and Sox/sry-sex/testis-determining and related HMG box factors, were found in the promoter region. Furthermore, real-time quantitative reverse transcription PCR assays were carried out to assess the mRNA expression of Cf SoxB 2 in different tissues. SoxB2 was highly expressed in the mantle, moderately in the digestive gland and gill, and weakly expressed in the gonad, kidney and adductor muscle. In male and female gonads at different developmental stages of reproduction, the expression levels of Cf SoxB2 were similar. Considering the specific expression and roles of SoxB 2 in other animals, in particular vertebrates, and the fact that there are many pallial nerves in the mantle, cerebral ganglia in the digestive gland and gill nerves in gill, we propose a possible essential role in nervous tissue function for Sox B 2 in C. farreri.

  17. Demographic processes underlying subtle patterns of population structure in the scalloped hammerhead shark, Sphyrna lewini.

    PubMed

    Nance, Holly A; Klimley, Peter; Galván-Magaña, Felipe; Martínez-Ortíz, Jimmy; Marko, Peter B

    2011-01-01

    Genetic diversity (θ), effective population size (N(e)), and contemporary levels of gene flow are important parameters to estimate for species of conservation concern, such as the globally endangered scalloped hammerhead shark, Sphyrna lewini. Therefore, we have reconstructed the demographic history of S. lewini across its Eastern Pacific (EP) range by applying classical and coalescent population genetic methods to a combination of 15 microsatellite loci and mtDNA control region sequences. In addition to significant population genetic structure and isolation-by-distance among seven coastal sites between central Mexico and Ecuador, the analyses revealed that all populations have experienced a bottleneck and that all current values of θ are at least an order of magnitude smaller than ancestral θ, indicating large decreases in N(e) (θ = 4N(e)μ), where μ is the mutation rate. Application of the isolation-with-migration (IM) model showed modest but significant genetic connectivity between most sampled sites (point estimates of Nm = 0.1-16.7), with divergence times (t) among all populations significantly greater than zero. Using a conservative (i.e., slow) fossil-based taxon-specific phylogenetic calibration for mtDNA mutation rates, posterior probability distributions (PPDs) for the onset of the decline in N(e) predate modern fishing in this region. The cause of decline over the last several thousand years is unknown but is highly atypical as a post-glacial demographic history. Regardless of the cause, our data and analyses suggest that S. lewini was far more abundant throughout the EP in the past than at present. PMID:21789171

  18. Effects of benzo(k)fluoranthene exposure on the biomarkers of scallop Chlamys farreri.

    PubMed

    Pan, Luqing; Ren, Jiayun; Liu, Jing

    2005-07-01

    Scallops (Chlamys ferrari) were cultured for 30 days in seawater containing benzo(k)fluoranthene (BkF) at 0.5, 1.0 and 10.0 microg/L. No effects were noted on 7-ethoxyresorufin O-deethylase (EROD) activity in digestive gland at low concentrations (0.5 and 1 microg/L) of BkF, but BkF increased the glutathione-S-transferase (GST) activity. At 10 microg/L BkF increased EROD activity significantly, and depressed GST activity. Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) in digestive gland increased significantly in 0.5 and 1 microg/L BkF. In 10 microg/L concentrations of BkF, the activity of three antioxidant enzymes increased first and reached a peak after a few days, before tapering off towards the end of the 30 day exposure. In high concentrations of BkF, activity of three antioxidant enzymes in gill showed an early peak (12 h), before dropping off. Lipid peroxidation (LPO) levels increased along with sampling times, and there were time- and concentration-effects between LPO levels and BkF. The responses of the gills and the digestive gland were not always parallel which can be explained by differences in the bioavailability of the toxicant. The performance of each biomarker is assessed in the context of the role and advantages of selecting a battery of biomarkers for detecting contamination problems. The use of C. ferrari as a sentinel species for biomonitoring potential toxic effects in situ is discussed as well as mechanisms of BKF toxicity and alexipharmic strategies of C. ferrari. PMID:16095977

  19. Demographic Processes Underlying Subtle Patterns of Population Structure in the Scalloped Hammerhead Shark, Sphyrna lewini

    PubMed Central

    Nance, Holly A.; Klimley, Peter; Galván-Magaña, Felipe; Martínez-Ortíz, Jimmy; Marko, Peter B.

    2011-01-01

    Genetic diversity (θ), effective population size (Ne), and contemporary levels of gene flow are important parameters to estimate for species of conservation concern, such as the globally endangered scalloped hammerhead shark, Sphyrna lewini. Therefore, we have reconstructed the demographic history of S. lewini across its Eastern Pacific (EP) range by applying classical and coalescent population genetic methods to a combination of 15 microsatellite loci and mtDNA control region sequences. In addition to significant population genetic structure and isolation-by-distance among seven coastal sites between central Mexico and Ecuador, the analyses revealed that all populations have experienced a bottleneck and that all current values of θ are at least an order of magnitude smaller than ancestral θ, indicating large decreases in Ne (θ = 4Neμ), where μ is the mutation rate. Application of the isolation-with-migration (IM) model showed modest but significant genetic connectivity between most sampled sites (point estimates of Nm = 0.1–16.7), with divergence times (t) among all populations significantly greater than zero. Using a conservative (i.e., slow) fossil-based taxon-specific phylogenetic calibration for mtDNA mutation rates, posterior probability distributions (PPDs) for the onset of the decline in Ne predate modern fishing in this region. The cause of decline over the last several thousand years is unknown but is highly atypical as a post-glacial demographic history. Regardless of the cause, our data and analyses suggest that S. lewini was far more abundant throughout the EP in the past than at present. PMID:21789171

  20. Inheritance pattern of microsatellite loci and their use for kinship analysis in the Japanese scallop Patinopecten yessoensis

    NASA Astrophysics Data System (ADS)

    Xu, Kefeng; Li, Qi

    2009-06-01

    The inheritance mode of seven microsatellite markers was investigated in Patinopecten yessoensis larvae from four controlled crosses, and the feasibility of using these markers for kinship estimation was also examined. All the seven microsatellite loci were compatible with Mendelian inheritance. Neither sex-linked barriers to transmission nor major barriers to fertilization between gametes from the parents were evident. Two of the seven loci showed the presence of null alleles in two families, suggesting the need to conduct comprehensive species-specific inheritance studies for microsatellite loci used in population genetic studies. However, even if the null allele heterozygotes were considered as homozygotes in the calculation of genetic distance, offspring from four families were all unambiguously discriminated in the neighbor-joining dendrogram. This result indicates that the microsatellite markers used may be capable of discriminating between related and unrelated scallop larvae in the absence of pedigree information, and of investigating the effective number of parents contributing to the hatchery population of the Japanese scallop.

  1. Accumulation of γ-aminobutyric acid by Enterococcus avium 9184 in scallop solution in a two-stage fermentation strategy.

    PubMed

    Yang, Haoyue; Xing, Ronge; Hu, Linfeng; Liu, Song; Li, Pengcheng

    2016-07-01

    In this study, a new bacterial strain having a high ability to produce γ-aminobutyric acid (GABA) was isolated from naturally fermented scallop solution and was identified as Enterococcus avium. To the best of our knowledge, this is the first study to prove that E. avium possesses glutamate decarboxylase activity. The strain was then mutagenized with UV radiation and was designated as E. avium 9184. Scallop solution was used as the culture medium to produce GABA. A two-stage fermentation strategy was applied to accumulate GABA. In the first stage, cell growth was regulated. Optimum conditions for cell growth were pH, 6.5; temperature, 37°C; and glucose concentration, 10 g·L(-1) . This produced a maximum dry cell mass of 2.10 g·L(-1) . In the second stage, GABA formation was regulated. GABA concentration reached 3.71 g·L(-1) at 96 h pH 6.0, 37°C and initial l-monosodium glutamate concentration of 10 g·L(-1) . Thus, compared with traditional one-stage fermentation, the two-stage fermentation significantly increased GABA accumulation. These results provide preliminary data to produce GABA using E. avium and also provide a new approach to process and utilize shellfish. PMID:26200650

  2. Kicking it up a Notch for the best in show: Scalloped leads Yorkie into the haematopoietic arena

    PubMed Central

    Ferguson, Gabriel B; Martinez-Agosto, Julian A

    2014-01-01

    Maintenance and differentiation of progenitor cells is essential for proper organ development and adaptation to environmental stress and injury. In Drosophila melanogaster, the haematopietic system serves as an ideal model for interrogating the function of signaling pathways required for progenitor maintenance and cell fate determination. Here we focus on the role of the Hippo pathway effectors Yorkie and Scalloped in mediating and facilitating Notch signaling-mediated lineage specification in the lymph gland, the primary center for haematopoiesis within the developing larva. We discuss the regulatory mechanisms which promote Notch activity during normal haematopoiesis and its modulation during immune challenge conditions. We provide additional evidence establishing the hierarchy of signaling events during crystal cell formation, highlighting the relationship between Yorkie, Scalloped and Lozenge, while expanding on the role of Yorkie in promoting hemocyte survival and the developmental regulation of Notch and its ligand, Serrate, within the lymph gland. Finally, we propose additional areas of exploration that may provide mechanistic insight into the environmental and non-cell autonomous regulation of cell fate in the blood system. PMID:26151599

  3. Bioconversion of (13)C-labeled microalgal phytosterols to cholesterol by the Northern Bay scallop, Argopecten irradians irradians.

    PubMed

    Giner, José-Luis; Zhao, Hui; Dixon, Mark S; Wikfors, Gary H

    2016-02-01

    Bivalve mollusks lack de novo cholesterol biosynthesis capabilities and therefore rely upon dietary sources of sterols for rapid growth. Microalgae that constitute the main source of nutrition for suspension-feeding bivalves contain a diverse array of phytosterols, in most cases lacking cholesterol. Rapid growth of bivalves on microalgal diets with no cholesterol implies that some phytosterols can satisfy the dietary requirement for cholesterol through metabolic conversion to cholesterol, but such metabolic pathways have not been rigorously demonstrated. In the present study, stable isotope-labeled phytosterols were used to supplement a unialgal diet of Rhodomonas sp. and their biological transformation to cholesterol within scallop tissues was determined using (13)C-NMR spectroscopy. Scallops efficiently dealkylated ∆(5) C29 (24-ethyl) sterols to cholesterol, and the only C28 sterol that was dealkylated efficiently possessed the 24(28)-double bond. Non-metabolized dietary phytosterols accumulated in the soft tissues. Observed formation of ∆(5,7) sterols (provitamin D) from ∆(5) sterols may represent initiation of steroid hormone (possibly ecdysone) biosynthesis. These findings provide a key component necessary for formulation of nutritionally complete microalgal diets for hatchery production of seed for molluscan aquaculture. PMID:26577022

  4. Novel 14-nm Scallop-Shaped FinFETs (S-FinFETs) on Bulk-Si Substrate.

    PubMed

    Xu, Weijia; Yin, Huaxiang; Ma, Xiaolong; Hong, Peizhen; Xu, Miao; Meng, Lingkuan

    2015-12-01

    In this study, novel p-type scallop-shaped fin field-effect transistors (S-FinFETs) are fabricated using an all-last high-k/metal gate (HKMG) process on bulk-silicon (Si) substrates for the first time. In combination with the structure advantage of conventional Si nanowires, the proposed S-FinFETs provide better electrostatic integrity in the channels than normal bulk-Si FinFETs or tri-gate devices with rectangular or trapezoidal fins. It is due to formation of quasi-surrounding gate electrodes on scalloping fins by a special Si etch process. The entire integration flow of the S-FinFETs is fully compatible with the mainstream all-last HKMG FinFET process, except for a modified fin etch process. The drain-induced barrier lowering and subthreshold swing of the fabricated p-type S-FinFETs with a 14-nm physical gate length are 62 mV/V and 75 mV/dec, respectively, which are much better than those of normal FinFETs with a similar process. With an improved short-channel-effect immunity in the channels due to structure modification, the novel structure provides one of possibilities to extend the FinFET scalability to sub-10-nm nodes with little additional process cost. PMID:26055484

  5. Genome Sequence of Vibrio VPAP30, Isolated from an Episode of Massive Mortality of Reared Larvae of the Scallop Argopecten purpuratus

    PubMed Central

    Rojas, Rodrigo; Miranda, Claudio D.; Romero, Jaime; Asenjo, Freddy; Valderrama, Katherinne; Segovia, Cristopher

    2015-01-01

    We report here the 5.167-Mbp draft genome sequence of Vibrio VPAP30, isolated from an Argopecten purpuratus larval culture. Vibrio VPAP30 is the etiological agent of a vibriosis outbreak causing a complete collapse of a larval culture of the scallop A. purpuratus, which occurred in a commercial hatchery in Chile. PMID:26159530

  6. Genome Sequence of Vibrio VPAP30, Isolated from an Episode of Massive Mortality of Reared Larvae of the Scallop Argopecten purpuratus.

    PubMed

    Rojas, Rodrigo; Miranda, Claudio D; Romero, Jaime; Asenjo, Freddy; Valderrama, Katherinne; Segovia, Cristopher; Ugalde, Juan A; Santander, Javier

    2015-01-01

    We report here the 5.167-Mbp draft genome sequence of Vibrio VPAP30, isolated from an Argopecten purpuratus larval culture. Vibrio VPAP30 is the etiological agent of a vibriosis outbreak causing a complete collapse of a larval culture of the scallop A. purpuratus, which occurred in a commercial hatchery in Chile. PMID:26159530

  7. Contribution of calcium and potassium permeability changes to the off response of scallop hyperpolarizing photoreceptors.

    PubMed Central

    Cornwall, M C; Gorman, A L

    1979-01-01

    1. The membrane response of the distal photoreceptors in the retina of the scallop Pectin irradians to the termination of a bright white light (off response) is shown to be composed of the decay of the hyperpolarizing receptor potential and an action potential with slow kinetics. 2. The action potential can be produced in darkness in the absence of external Na+ ions by membrane depolarization. 3. The action potential is maintained by replacement of external Ca2+ with Sr2+ or Ba2+, but not by Mg2+. In normal external Ca2+ (9mM), the action potential is abolished by the addition of the Ca2+ inhibitors, La3+, Co2+, and Mn2+ or the organic Ca2+ antagonist D-600. 4. Elevated external Ca2+ concentrations increase the rate of rise and peak amplitude of the action potential as well as the rate of repolarization and after hyperpolarization, but decrease the duration. 5. The rate of rise and peak amplitude of the action potential are increased by the K+ antagonists tetraethylammonium (TEA) 4-amino-phyridine (4-AP), Ba2+ and procaine. The antagonists have different effects on subsequent phases of the response, however. External TEA and Ba2+ increase the duration, but decrease the rate of repolarization and abolish the after hyperpolarization, whereas external 4-AP and procaine increase the rate of repolarization, decrease the duration and increase the after hyperpolarization. 6. The ratio of the Ca2+ to K+ permeability (P Ca/P K) estimated from the constant field equation at the peak of the action potential in different external Ca2+ concentrations is close to 1. 7. The maximum rate of rise and the peak amplitude of the action potential are increased by membrane hyperpolarization and decreased by membrane depolarization. They are decreased by background light intensity relative to their value in the dark. 8. In normal ASW the action potential can be identified during the off response as a small overshoot of membrane potential relative to its value in the dark. 9. The rate of

  8. Organohalogen compounds and their metabolites in the blood of Japanese amberjack (Seriola quinqueradiata) and scalloped hammerhead shark (Sphyrna lewini) from Japanese coastal waters.

    PubMed

    Nomiyama, Kei; Uchiyama, Yukiko; Horiuchi, Satoko; Eguchi, Akifumi; Mizukawa, Hazuki; Hirata, Sawako Horai; Shinohara, Ryota; Tanabe, Shinsuke

    2011-10-01

    Information on accumulation of polychlorinated biphenyl metabolites (OH-PCBs) and hydroxylated polybrominated diphenyl ethers (OH-PBDEs) in the blood of marine fish is limited. The present study, we determined the residue levels and patterns of PCBs, OH-PCBs, PBDEs, OH-PBDEs and methoxylated PBDEs (MeO-PBDEs) in the blood collected from scalloped hammerhead shark (Sphyrna lewini) and Japanese amberjack (Seriola quinqueradiata), species of predatory fish at Japanese coastal waters. The predominant homologues found in Japanese amberjacks were mono- and di-chlorinated OH-PCBs, and scalloped hammerhead sharks were octa-chlorinated OH-PCBs. The predominant OH-PCB isomers were lower-chlorinated OH-PCBs such as 6OH-CB2 and 2'OH-CB9 in Japanese amberjacks. This result suggests that exposure of Japanese amberjacks to lower-chlorinated OH-PCBs might be from the ambient aquatic environment. In scalloped hammerhead sharks, 4,4'diOH-CB202, 4OH-CB201 and 4OH-CB146 were the predominant isomers accounting for approximately 60% of the total OH-PCBs. The predominant MeO-PBDE isomers were 6MeO-BDE47 followed by 2'MeO-BDE68 in both species. As for OH-PBDE isomers, 6OH-BDE47 was predominant followed by 2'OH-BDE68 in Japanese amberjacks and scalloped hammerhead sharks. Residue levels of ΣMeO-PBDEs and ΣOH-PBDEs showed a significant positive correlation (p=0.029). This result suggests that MeO-PBDEs and OH-PBDEs share a common source or a metabolic pathway in fishes. Characteristic differences found in the profiles of OH-PCBs and OH-PBDEs in Japanese amberjack and scalloped hammerhead shark show the need for further studies on the differences in exposure profiles, metabolic capacities and toxic effects in fish. PMID:21782210

  9. Cloning and differential expression of a novel toll-like receptor gene in noble scallop Chlamys nobilis with different total carotenoid content.

    PubMed

    Lu, Yeqing; Zheng, Huaiping; Zhang, Hongkuan; Yang, Jianqin; Wang, Qiang

    2016-09-01

    To investigate whether toll like receptors (TLRs) genes do have an immune influence on noble scallop Chlamys nobilis under pathogen stress, acute challenges lasting 48 h to Vibrio parahaemolyticus, lipopolysaccharide (LPS), polyinosinic polycytidylic acid (Poly I:C), and PBS were conducted in two scallop stains of orange and brown with different carotenoids content. A novel toll-like receptor gene called CnTLR-1 was cloned and its transcripts under different challenges were determined. Meantime, total carotenoids content (TCC) of different immune responses were determined to investigate whether there was a relationship between gene expression and carotenoids content. The full length cDNA of CnTLR-1 is 2982 bp with an open reading frame (ORF) of 1920 bp encoding 639-deduced amino acids, which contains five leucine-rich repeats (LRR), two LRR-C-terminal (LRRCT) motifs and a LRR-N-terminal (LRRNT) motif in the extracellular domain, a transmembrane domain and a Toll/Interleukin-1 Receptor (TIR) of 138-amino acids in the cytoplasmic region. Phylogenetic tree analysis showed that CnTLR-1 could be clustered with mollusk TLRs into one group and especially was related closely to Crassostrea gigas and Mytilus galloprovincialis TLRs. CnTLR-1 transcripts were detected in decreasing levels in the mantle, hemocytes, gill, kidney, gonad, hepatopancreas, intestines and adductor. Compared with PBS control group, CnTLR-1 transcripts were up-regulated in V. parahaemolyticus, LPS and Poly I:C groups. Further, CnTLR-1 transcripts were significantly higher in orange scallops than that of brown ones with and without pathogenic challenges. TCC, which is higher in orange scallops, was initially increased and then decreased during a 48 h immune challenge in the hemocytes. The present results indicate that CnTLR-1 is an important factor involved in the immune defense against pathogens in the noble scallop. PMID:27403592

  10. Fusarium solani fungal infection of the lateral line canal system in captive scalloped hammerhead sharks (Sphyrna lewini) in Hawaii.

    PubMed

    Crow, G L; Brock, J A; Kaiser, S

    1995-10-01

    Two of five scalloped hammerhead sharks (Sphyrna lewini) captured May 1987 in Hawaii (USA) developed granulomatous exudative mycotic dermatitis localized in the lateral line canal system. The lesion initially was noted in the cephalic canals, but over a period of months extended into the lateral canal. Fusarium solani and Vibrio spp. were isolated from the canal exudate of both sharks. Bacterial colonies were not observed in the canal walls or surrounding tissues. Fusarium solani infection resulted in a chronic physical and behavioral deterioration of the two sharks; one shark was euthanized in September 1988 and the other in July 1989. This is the first report of Fusarium solani infection in the lateral line canal system and the third account in hammerhead sharks. PMID:8592393

  11. Antagonists of the cGMP-gated conductance of vertebrate rods block the photocurrent in scallop ciliary photoreceptors.

    PubMed Central

    Gomez, M P; Nasi, E

    1997-01-01

    1. Hyperpolarizing scallop photoreceptors, like vertebrate rods, use cGMP as an internal messenger and their light-sensing structure is also of ciliary origin. To ascertain possible functional similarities between the light-sensitive conductances in the two classes of visual cells, we examined in scallop photoreceptors the effects of several antagonists of the photocurrent of rods. 2. Extracellular application of L-cis-diltiazem rapidly and reversibly suppressed the photocurrent. The effect was stereospecific and dose dependent, with a K1/2 of approximately 400 microM. Intracellular dialysis at lower doses (100-200 microM) also induced a substantial inhibition. 3. L-cis-Diltiazem reduced the light-activated conductance without shifting the intensity-response curve. Furthermore, the drug also blocked the current directly evoked by application of cGMP. These observations indicate that the inhibitory effects result from blockage of the conductance, rather than from impairment of the activating cascade. 4. The fractional blockage increased e-fold per approximately 55 mV depolarization, regardless of the side of drug application, as if the charged form of L-cis-diltiazem can only access the blocking site from the intracellular compartment. 5. The amiloride derivative 3',4'-dichlorobenzamil potently suppressed the photocurrent (K1/2 approximately 5 microM), without affecting its kinetics or operating range. Amiloride itself was also effective at higher concentrations. 6. The pharmacological resemblance of these light-dependent channels to those of rods and cones indicates that significant aspects of the transduction cascade are conserved across disparate sensory cells of ciliary origin. PMID:9147324

  12. Identification of Male Gametogenesis Expressed Genes from the Scallop Nodipecten subnodosus by Suppressive Subtraction Hybridization and Pyrosequencing

    PubMed Central

    Llera-Herrera, Raúl; García-Gasca, Alejandra; Abreu-Goodger, Cei; Huvet, Arnaud; Ibarra, Ana M.

    2013-01-01

    Despite the great advances in sequencing technologies, genomic and transcriptomic information for marine non-model species with ecological, evolutionary, and economical interest is still scarce. In this work we aimed to identify genes expressed during spermatogenesis in the functional hermaphrodite scallop Nodipecten subnodosus (Mollusca: Bivalvia: Pectinidae), with the purpose of obtaining a panel of genes that would allow for the study of differentially transcribed genes between diploid and triploid scallops in the context of meiotic arrest and reproductive sterility. Because our aim was to isolate genes involved in meiosis and other testis maturation-related processes, we generated suppressive subtractive hybridization libraries of testis vs. inactive gonad. We obtained 352 and 177 ESTs by clone sequencing, and using pyrosequencing (454-Roche) we maximized the identified ESTs to 34,276 reads. A total of 1,153 genes from the testis library had a blastx hit and GO annotation, including genes specific for meiosis, spermatogenesis, sex-differentiation, and transposable elements. Some of the identified meiosis genes function in chromosome pairing (scp2, scp3), recombination and DNA repair (dmc1, rad51, ccnb1ip1/hei10), and meiotic checkpoints (rad1, hormad1, dtl/cdt2). Gene expression analyses in different gametogenic stages in both sexual regions of the gonad of meiosis genes confirmed that the expression was specific or increased towards the maturing testis. Spermatogenesis genes included known testis-specific ones (kelch-10, shippo1, adad1), with some of these known to be associated to sterility. Sex differentiation genes included one of the most conserved genes at the bottom of the sex-determination cascade (dmrt1). Transcript from transposable elements, reverse transcriptase, and transposases in this library evidenced that transposition is an active process during spermatogenesis in N. subnodosus. In relation to the inactive library, we identified 833

  13. Effects of free oxygen radicals on Ca2+ release mechanisms in the sarcoplasmic reticulum of scallop (Pecten jacobaeus) adductor muscle.

    PubMed

    Burlando, B; Viarengo, A; Pertica, M; Ponzano, E; Orunesu, M

    1997-08-01

    In vitro oxyradical effects on SR Ca2+ regulation were studied by using a SR-containing cell-free preparation from scallop (Pecten jacobaeus) adductor muscle. Ca2+ variations were fluorimetrically detected after incubation with Fluo-3 in the presence of ATP. Exposure to Fe3+/ascorbate produced dose-dependent Ca2+ release from SR vesicles, eventually leading to massive Ca2+ loss. Exposure to hypoxanthine/xanthine oxidase also caused Ca2+ release but at a much slower rate. Pre-incubations with catalase or with the hydroxyl radical scavenger KMBA led to a significant decrease in the Fe3+/ascorbate-induced Ca2+ release rate and to a delay of massive Ca2+ loss. Pre-incubations with GSH or DTT strongly reduced the Ca2+ release caused by Fe3+/ascorbate and, moreover, they prevented massive Ca2+ loss from SR vesicles. Addition of GSH or DTT after Fe3+/ascorbate promptly reduced the Ca2+ release rate and delayed massive Ca2+ release. Pre-incubation with the SR Ca2+ channel blocker ruthenium red strongly reduced the Ca2+ release caused by Fe3+/ascorbate, and also prevented massive Ca2+ loss. In the presence of ruthenium red, Fe3+/ascorbate treatments followed by Ca2+ addition revealed that Ca2+ uptake inhibition was slower than Ca2+ release. Taken together, data showed that free radicals and, in particular, hydroxyl radicals, affected the scallop SR Ca2+ regulation. This mainly occurred through Ca2+ channel opening, most likely triggered by sulfhydryl oxidation, which eventually led to massive Ca2+ release from SR vesicles. The demonstration of a specific effect of oxyradicals on SR Ca2+ channels is in line with their possible involvement in cell signaling. PMID:9292226

  14. Technical report: Marine mammals study number 6. Movements of weanling and adult female sea otters in Prince William Sound, Alaska, after the t/v Exxon Valdez oil spill. Marine mammal study 6-12. Exxon Valdez oil spill state/federal natural resource damage assessment final report

    SciTech Connect

    Monnett, C.; Rotterman, L.M.

    1995-05-01

    Ninety-six adult female sea otters and 64 weanling sea otters were instrumented with implanted radio-transmitters in Prince William Sound during 1989-1990 and monitored until November, 1991. Observations of the movements of adult female and weanling sea otters in prince William Sound indicated no tendency for individuals to emigrate from, or immigrate to, the area affected by oil spilled from the Exxon Valdez. This finding indicates that the study groups of sea otters categorized as `western Prince William Sound oil-spill treatment` otters and `eastern Prince William Sound control` otters are indeed distinct groups of individuals. No tendency was observed for recently weaned sea otters to exhibit a preference for habitat units based on the likelihood that they would encounter spilled oil therein. Finally, data reported suggest that the recovery of the sea otter population in the oil spill affected region of Prince William Sound will likely be a direct function of the rates of survival and reproduction of the sea otters in the affected habitat with little or no influence from emigration or immigration.

  15. Nuclear and mtDNA lineage diversity in wild and cultured Pacific lion-paw scallop, Nodipecten subnodosus (Baja California Peninsula, Mexico).

    PubMed

    Petersen, Jessica L; Ibarra, Ana Maria; May, Bernie

    2010-01-01

    Pacific lion-paw scallops were collected from natural aggregations in Laguna Ojo de Liebre (Pacific Ocean), the Gulf of California, and from aquaculture facilities for genetic diversity analyses. Mitochondrial DNA sequencing uncovered two highly supported clades separated by 2.5% divergence. Data from ten microsatellite markers suggest individuals from these mitogroups are introgressed, raising questions about the mitotype origin. Some evidence suggests gene flow between La Paz and Ojo de Liebre; otherwise the Gulf of California and Ojo de Liebre are acting as two distinct populations. It is unclear whether translocations between sites have influenced the observed genetic structure or whether gene flow has been facilitated by past geologic events. Finally, scallops spawned for aquaculture are unique from the wild and have significantly less diversity. These results warrant the attention of managers and producers who should work to monitor and conserve genetic diversity in both wild and aquaculture populations. PMID:24391254

  16. Comparison of total lipids and fatty acids from liver, heart and abdominal muscle of scalloped (Sphyrna lewini) and smooth (Sphyrna zygaena) hammerhead sharks.

    PubMed

    Davidson, Bruce Clement; Nel, Wynand; Rais, Afsha; Namdarizandi, Vahid; Vizarra, Scott; Cliff, Geremy

    2014-01-01

    Liver, heart and abdominal muscle samples from scalloped (Sphyrna lewini) and smooth (Sphyrna zygaena) hammerhead sharks were analysed to characterise their lipid and fatty acid profiles. Samples were compared both between and within species, but there were no significant differences in total lipids for either comparison, although much greater total amounts were found in the liver samples. Within the individual fatty acids, the only significant differences were greater amounts of 22:6n-3, total n-3 polyunsaturates and total polyunsaturates in smooth, when compared to scalloped, hammerhead liver. This may reflect the more wide spread distribution of this species into cooler waters. Within both species the liver levels of the same fatty acid fractions decreased from spring to summer, which may correlate with changes in fatty acid profile to adapt to any differences in amount or species of prey consumed, or other considerations, eg. buoyancy, however there was no data to clarify this. PMID:25279312

  17. A Scallop Nitric Oxide Synthase (NOS) with Structure Similar to Neuronal NOS and Its Involvement in the Immune Defense

    PubMed Central

    Jiang, Qiufen; Zhou, Zhi; Wang, Leilei; Wang, Lingling; Yue, Feng; Wang, Jingjing; Song, Linsheng

    2013-01-01

    Background Nitric oxide synthase (NOS) is responsible for synthesizing nitric oxide (NO) from L-arginine, and involved in multiple physiological functions. However, its immunological role in mollusc was seldom reported. Methodology In the present study, an NOS (CfNOS) gene was identified from the scallop Chlamys farreri encoding a polypeptide of 1486 amino acids. Its amino acid sequence shared 50.0~54.7, 40.7~47.0 and 42.5~44.5% similarities with vertebrate neuronal (n), endothelial (e) and inducible (i) NOSs, respectively. CfNOS contained PDZ, oxygenase and reductase domains, which resembled those in nNOS. The CfNOS mRNA transcripts expressed in all embryos and larvae after the 2-cell embryo stage, and were detectable in all tested tissues with the highest level in the gonad, and with the immune tissues hepatopancreas and haemocytes included. Moreover, the immunoreactive area of CfNOS distributed over the haemocyte cytoplasm and cell membrane. After LPS, β-glucan and PGN stimulation, the expression level of CfNOS mRNA in haemocytes increased significantly at 3 h (4.0-, 4.8- and 2.7-fold, respectively, P < 0.01), and reached the peak at 12 h (15.3- and 27.6-fold for LPS and β-glucan respectively, P < 0.01) and 24 h (17.3-fold for PGN, P < 0.01). In addition, TNF-α also induced the expression of CfNOS, which started to increase at 1 h (5.2-fold, P < 0.05) and peaked at 6 h (19.9-fold, P < 0.01). The catalytic activity of the native CfNOS protein was 30.3 ± 0.3 U mgprot-1, and it decreased significantly after the addition of the selective inhibitors of nNOS and iNOS (26.9 ± 0.4 and 29.3 ± 0.1 U mgprot-1, respectively, P < 0.01). Conclusions These results suggested that CfNOS, with identical structure with nNOS and similar enzymatic characteristics to nNOS and iNOS, played the immunological role of iNOS to be involved in the scallop immune defense against PAMPs and TNF-α. PMID:23922688

  18. A Consensus Microsatellite-Based Linkage Map for the Hermaphroditic Bay Scallop (Argopecten irradians) and Its Application in Size-Related QTL Analysis

    PubMed Central

    Li, Hongjun; Liu, Xiao; Zhang, Guofan

    2012-01-01

    Bay scallop (Argopecten irradians) is one of the most economically important aquaculture species in China. In this study, we constructed a consensus microsatellite-based genetic linkage map with a mapping panel containing two hybrid backcross-like families involving two subspecies of bay scallop, A. i. irradians and A. i. concentricus. One hundred sixty-one microsatellite and one phenotypic (shell color) markers were mapped to 16 linkage groups (LGs), which corresponds to the haploid chromosome number of bay scallop. The sex-specific map was 779.2 cM and 781.6 cM long in female and male, respectively, whereas the sex-averaged map spanned 849.3 cM. The average resolution of integrated map was 5.9 cM/locus and the estimated coverage was 81.3%. The proportion of distorted markers occurred more in the hybrid parents, suggesting that the segregation distortion was possibly resulted from heterospecific interaction between genomes of two subspecies of bay scallop. The overall female-to-male recombination rate was 1.13∶1 across all linked markers in common to both parents, and considerable differences in recombination also existed among different parents in both families. Four size-related traits, including shell length (SL), shell height (SH), shell width (SW) and total weight (TW) were measured for quantitative trait loci (QTL) analysis. Three significant and six suggestive QTL were detected on five LGs. Among the three significant QTL, two (qSW-10 and qTW-10, controlling SW and TW, respectively) were mapped on the same region near marker AiAD121 on LG10 and explained 20.5% and 27.7% of the phenotypic variance, while the third (qSH-7, controlling SH) was located on LG7 and accounted for 15.8% of the phenotypic variance. Six suggestive QTL were detected on four different LGs. The linkage map and size-related QTL obtained in this study may facilitate marker-assisted selection (MAS) in bay scallop. PMID:23077533

  19. Coupling experimental and field-based approaches to decipher carbon sources in the shell of the great scallop, Pecten maximus (L.)

    NASA Astrophysics Data System (ADS)

    Marchais, V.; Richard, J.; Jolivet, A.; Flye-Sainte-Marie, J.; Thébault, J.; Jean, F.; Richard, P.; Paulet, Y.-M.; Clavier, J.; Chauvaud, L.

    2015-11-01

    This research investigated how the carbon isotopic composition of food source (δ13Cfood) and dissolved inorganic carbon (δ13CDIC) influences the carbon isotopic composition of Pecten maximus shells (δ13Cshell) under both experimental and natural conditions. The objectives are to better understand the relationship between P. maximus and its environment, and to specifically distinguish conditions under which calcification is influenced by respired CO2 derived from food sources versus conditions in which calcification uses inorganic carbon from seawater. Laboratory experiment investigated carbon incorporation into shell carbonates by maintaining scallops under conditions where the stable carbon isotopic composition of food sources was considerably depleted (-54‰), relative to values observed in the natural environment (-21‰). Laboratory experiment ran for 78 days under three temperature conditions, 15 °C, 21 °C and 25 °C. A survey of the environmental parameters and stable carbon isotopic composition into shell carbonate of natural population of P. maximus was also realized during the same year in the Bay of Brest, France. Data collected from both laboratory experiment and the natural environment confirmed that both δ13CDIC and δ13Cfood influence δ13Cshell values and that organic carbon incorporation (CM) averages about 10% (4.3-6.8% under experimental conditions and 1.9-16.6% in the natural environment). The shift in stable carbon isotopic composition from the uptake of depleted food sources under experimental conditions realized a marked divergence in the predicted equilibrium between calcium carbonate and ambient bicarbonate, relative to the natural environment. This offset was 1.7 ± 0.6‰ for scallops in their natural environment and 2.5 ± 0.5 and 3.2 ± 0.9‰ for scallops under experimental conditions at water temperatures of 15 °C and 21 °C, respectively. The offset of 3‰ for scallops subjected to laboratory experiment could not be explained

  20. Modelling larval dispersal of the king scallop ( Pecten maximus) in the English Channel: examples from the bay of Saint-Brieuc and the bay of Seine

    NASA Astrophysics Data System (ADS)

    Nicolle, Amandine; Dumas, Franck; Foveau, Aurélie; Foucher, Eric; Thiébaut, Eric

    2013-06-01

    The king scallop ( Pecten maximus) is one of the most important benthic species of the English Channel as it constitutes the first fishery in terms of landings in this area. To support strategies of spatial fishery management, we develop a high-resolution biophysical model to study scallop dispersal in two bays along the French coasts of the English Channel (i.e. the bay of Saint-Brieuc and the bay of Seine) and to quantify the relative roles of local hydrodynamic processes, temperature-dependent planktonic larval duration (PLD) and active swimming behaviour (SB). The two bays are chosen for three reasons: (1) the distribution of the scallop stocks in these areas is well known from annual scallop stock surveys, (2) these two bays harbour important fisheries and (3) scallops in these two areas present some differences in terms of reproductive cycle and spawning duration. The English Channel currents and temperature are simulated for 10 years (2000-2010) with the MARS-3D code and then used by the Lagrangian module of MARS-3D to model the transport. Results were analysed in terms of larval distribution at settlement and connectivity rates. While larval transport in the two bays depended both on the tidal residual circulation and the wind-induced currents, the relative role of these two hydrodynamic processes varied among bays. In the bay of Saint-Brieuc, the main patterns of larval dispersal were due to tides, the wind being only a source of variability in the extent of larval patch and the local retention rate. Conversely, in the bay of Seine, wind-induced currents altered both the direction and the extent of larval transport. The main effect of a variable PLD in relation to the thermal history of each larva was to reduce the spread of dispersal and consequently increase the local retention by about 10 % on average. Although swimming behaviour could influence larval dispersal during the first days of the PLD when larvae are mainly located in surface waters, it has a

  1. Holocene sequence stratigraphy and sea level rise, south Florida margin

    SciTech Connect

    Locker, S.D.; Hine, A.C.; Toscano, M.A. ); Shinn, E.A. )

    1993-03-01

    Fluctuation of late Quaternary sea level has been an important factor controlling erosional and depositional patterns on portions of the outer shelf and slope seaward of the lower-most Florida Keys. Studies in this area using high-resolution seismic, side scan sonar, bottom grab sampling, and submersible dives document a Holocene succession of lowstand wedge, transgressive, and highstand systems tract facies which have formed in response to sea level flooding the margin. The last lowstand of sea level is recorded by widespread scallop-like erosion along the slope front, occurring as deep as 150 m. Upslope from the erosional cuts, the transgressive systems tract includes a series of drowned shoreline (and reef) accumulations in the depth range 60--110 meters. Rocks recovered form paleoshorelines near 100 m water depth were submarine-cemented grainstones composed of early Holocene shallow-water carbonates. This transgressive section is partially buried by weakly laminated to reflection free fined-grained deposits of the highstand systems tract. These recent muddy silts reflect a sediment source initiated by flooding of the inner shelf platform and subsequent alongslope transport of fines exported offbank. Two very continuous, linear, and thin (< 5 m thick) paleoshorelines at 60--62 m and 66--68 m reflect a response to a change in rate of sea-level rise across a low gradient surface. The deeper shoreline deposits, ranging from 75--110 m below sea level are isolated features and occur on steeper slopes. The character of preserved transgressive deposits suggests the Holocene rate of rise is punctuated. The lowest stand of sea level produced distinctive erosional features. Accretional transgressive deposits formed during the sea-level rise. Interactions between antecedent topography, bottom currents, and changes in sediment supply, slope gradients, and rate of sea-level rise are key factors controlling facies patterns, accumulation rates, and depositional geometries.

  2. Red Sea

    Atmospheric Science Data Center

    2013-04-16

    article title:  The Red Sea     View Larger Image ... Imaging SpectroRadiometer (MISR) image of the Red Sea was acquired on August 13, 2000. Located between the East African coast and the Saudi Arabian peninsula, the Red Sea got its name because the blooms of a type of algae,  Trichodesmium ...

  3. Bering Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Much of the Bering Sea is clear in this SeaWiFS image. The large expanse of bright aquamarine water is clearly visible. Credit: Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  4. Bering Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The skies of the Bering Sea were relatively clear again in this SeaWiFS image showing a band of aquamarine colored water. Credit: Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  5. Effect of increased pCO2 on early shell development in great scallop (Pecten maximus Lamarck) larvae

    NASA Astrophysics Data System (ADS)

    Andersen, S.; Grefsrud, E. S.; Harboe, T.

    2013-02-01

    As a result of high anthropogenic emission of CO2, partial pressure of carbon dioxide (pCO2) in the oceans has increased causing a drop in pH, known as ocean acidification (OA). Numerous studies have shown negative effects on marine invertebrates, and that the early life stages are the most sensitive to OA. We studied the effects on embryo and larvae of great scallop (Pecten maximus L.), using mean pCO2-levels of 477 (ambient), 821, 1184, and 1627 ppm. OA affected both survival and shell growth negatively after seven days. Growth was reduced with 5-10% when pCO2 increased from ambient 477 ppm to 1627 ppm, and survival based on egg number was reduced from 40.4% in the ambient group to 10.7% in the highest pCO2-group. Larvae/embryos stained with calcein one day after fertilization, showed fluorescence in the newly formed shell area indicating calcification of the shell already at the trochophore stage. Shell hinge deformities were observed at elevated pCO2-levels in trochophore larvae after two days. After seven days, deformities in both shell hinge and shell edge were observed in veliger larvae at elevated pCO2-levels. Although the growth showed a moderate reduction, survival rate and increased amount of deformed larvae indicates that P. Maximus larvae are affected by elevated pCO2 levels within the range of what is projected for the next century.

  6. Juvenile King Scallop, Pecten maximus, Is Potentially Tolerant to Low Levels of Ocean Acidification When Food Is Unrestricted

    PubMed Central

    Sanders, Matthew Burton; Bean, Tim P.; Hutchinson, Thomas H.; Le Quesne, Will J. F.

    2013-01-01

    The decline in ocean water pH and changes in carbonate saturation states through anthropogenically mediated increases in atmospheric CO2 levels may pose a hazard to marine organisms. This may be particularly acute for those species reliant on calcareous structures like shells and exoskeletons. This is of particular concern in the case of valuable commercially exploited species such as the king scallop, Pecten maximus. In this study we investigated the effects on oxygen consumption, clearance rates and cellular turnover in juvenile P. maximus following 3 months laboratory exposure to four pCO2 treatments (290, 380, 750 and 1140 µatm). None of the exposure levels were found to have significant effect on the clearance rates, respiration rates, condition index or cellular turnover (RNA: DNA) of individuals. While it is clear that some life stages of marine bivalves appear susceptible to future levels of ocean acidification, particularly under food limiting conditions, the results from this study suggest that where food is in abundance, bivalves like juvenile P. maximus may display a tolerance to limited changes in seawater chemistry. PMID:24023928

  7. Complete genome sequence of acute viral necrosis virus associated with massive mortality outbreaks in the Chinese scallop, Chlamys farreri

    PubMed Central

    2013-01-01

    Background Acute viral necrosis virus (AVNV) is the causative agent of a serious disease resulting in high mortality in cultured Chinese scallops, Chlamys farreri. We have sequenced and analyzed the complete genome of AVNV. Results The AVNV genome is a linear, double-stranded DNA molecule of 210,993 bp with a nucleotide composition of 38.5% G + C. A total of 123 open reading frames were predicted to encode functional proteins, ranging from 41 to 1,878 amino acid residues. The DNA sequence of AVNV is 97% identical to that of ostreid herpesvirus 1 (OsHV-1), and the amino acid sequences of the encoded proteins of these two viruses are 94-100% identical. The genomic organization of AVNV is similar to that of OsHV-1, and consists of two unique regions (170.4 kb and 3.4 kb, respectively), each flanked by two inverted repeats (7.6 kb and 10.2 kb, respectively), with a third unique region (1.5 kb) situated between the two internal repeats. Conclusions Our results indicate that AVNV is a variant of OsHV-1. The AVNV genome sequence provides information useful for understanding the evolution and divergence of OsHV-1 in marine molluscs. PMID:23566284

  8. Heated scallop-shell powder treatment for deactivation and removal of Listeria sp. biofilm formed at a low temperature.

    PubMed

    Shimamura, Nobumitsu; Irie, Fumio; Yamakawa, Takahiro; Kikuchi, Mikio; Sawai, Jun

    2015-01-01

    The ability of heated scallop-shell powder (HSSP) to work against Listeria sp. biofilm formed at a low temperature was investigated. A biofilm of L. innocua ATCC 33090 was grown on a glass plate at 15˚C for 15 days, then immersed in HSSP slurry. Following treatment, the disinfection ability of the HSSP against the biofilm was non-destructively quantified by conductimetric assay. The biofilm grown at 15˚C was less sensitive than that grown at 37˚C to HSSP treatment and alkaline treatment. The biofilm grown at 15˚C was completely deactivated by 30 min of HSSP treatment (10 mg/mL, pH 12.5). In contrast, after 30 min treatment with alkaline solution at pH 12.5 or sodium hypochlorite (100 ppm), the activity was reduced by only one order of magnitude. The disinfection efficacy of HSSP (10 mg/mL) against L. innocua is similar to or higher than that of sodium hypochlorite (200 ppm). Fluorescence microscopy validated the results of the conductimetric assay. Therefore, HSSP treatment is a potentially powerful alternative control agent against Listeria sp. biofilms that present hazards in the food industry. PMID:26133513

  9. Prevalence, Clinical Profile, Iron Status, and Subject-Specific Traits for Excessive Erythrocytosis in Andean Adults Living Permanently at 3,825 Meters Above Sea Level

    PubMed Central

    De Ferrari, Aldo; Miranda, J. Jaime; Gilman, Robert H.; Dávila-Román, Victor G.; León-Velarde, Fabiola; Rivera-Ch, Maria; Huicho, Luis; Bernabé-Ortiz, Antonio; Wise, Robert A.

    2014-01-01

    BACKGROUND: Excessive erythrocytosis (EE) is a prevalent condition in populations living at high altitudes (> 2,500 m above sea level). Few large population-based studies have explored the association between EE and multiple subject-specific traits including oxygen saturation, iron status indicators, and pulmonary function. METHODS: We enrolled a sex-stratified and age-stratified sample of 1,065 high-altitude residents aged ≥ 35 years from Puno, Peru (3,825 m above sea level) and conducted a standardized questionnaire and physical examination that included spirometry, pulse oximetry, and a blood sample for multiple clinical markers. Our primary objectives were to estimate the prevalence of EE, characterize the clinical profile and iron status indicators of subjects with EE, and describe subject-specific traits associated with EE. RESULTS: Overall prevalence of EE was 4.5% (95% CI, 3.3%-6.0%). Oxygen saturation was significantly lower among EE than non-EE group subjects (85.3% vs 90.1%, P < .001) but no difference was found in iron status indicators between both groups (P > .09 for all values). In multivariable logistic regression, we found that age ≥ 65 years (OR = 2.45, 95% CI, 1.16-5.09), male sex (3.86, 1.78-9.08), having metabolic syndrome (2.66, 1.27-5.75) or being overweight (5.20, 1.95-16.77), pulse oximetry < 85% (14.90, 6.43-34.90), and % predicted FVC < 80% (13.62, 4.40-41.80) were strongly associated with EE. Attributable fractions for EE were greatest for being overweight (26.7%), followed by male sex (21.5%), pulse oximetry < 85% (16.4%), having metabolic syndrome (14.4%), and % predicted FVC < 80% (9.3%). CONCLUSIONS: We found a lower prevalence of EE than in previous reports in the Peruvian Andes. Although the presence of hypoxemia and decreased vital capacity were strongly associated with excessive erythrocytosis, being overweight or having metabolic syndrome were associated with an important fraction of cases in our study population. PMID

  10. Functional characterization of a Δ5-like fatty acyl desaturase and its expression during early embryogenesis in the noble scallop Chlamys nobilis Reeve.

    PubMed

    Liu, Helu; Guo, Zhicheng; Zheng, Huaiping; Wang, Shuqi; Wang, Yajun; Liu, Wenhua; Zhang, Guofan

    2014-11-01

    Long-chain polyunsaturated fatty acids (LC-PUFAs) are essential in lots of important physiological processes, while, many marine species have no or limited ability of endogenous PUFA biosynthesis, normally due to the lack of key enzymes such as fatty acid desaturase (FAD). In this study, we isolated a scallop Chlamys nobilis cDNA with high homology to vertebrate FADs. Functional characterization in recombinant yeast Saccharomyces cerevisiae showed that scallop FAD exhibited Δ5-desaturation activity towards both saturated and PUFA substrates. Thus, it efficiently desaturated exogenously added PUFA C20:4(n - 3) and C20:3(n - 6) to C20:5(n - 3) (EPA) and C20:4(n - 6) (ARA) respectively. It also converted the yeast's endogenous C18:0 into C18:1(n - 13), and participated in the biosynthesis of non-methylene-interrupted FA by introducing a double bond to C20:3(n - 3) and C20:2(n - 6) in the Δ5 carbon. Temporal transcript profile of scallop FAD was studied during early embryonic development. High level of mRNA was found at the beginning of embryogenesis (egg) and noticeable decreases of were observed during larvae development, suggesting maternal FAD mRNA transfer to the embryo. Further, FAD transcripts were detected in all tissues analyzed, with the gonad and hepatopancreas showing the highest expression. PMID:25081650

  11. The cDNA cloning and mRNA expression of cytoplasmic Cu, Zn superoxide dismutase (SOD) gene in scallop Chlamys farreri.

    PubMed

    Ni, Duojiao; Song, Linsheng; Gao, Qiang; Wu, Longtao; Yu, Yundong; Zhao, Jianmin; Qiu, Limei; Zhang, Huan; Shi, Fangfang

    2007-11-01

    Cu, Zn superoxide dismutases (SODs) are metalloenzymes that represent one important line of defence against reactive oxygen species (ROS). A cytoplasmic Cu, Zn SOD cDNA sequence was cloned from scallop Chlamys farreri by the homology-based cloning technique. The full-length cDNA of scallop cytoplasmic Cu, Zn SOD (designated CfSOD) was 1022 bp with a 459 bp open reading frame encoding a polypeptide of 153 amino acids. The predicted amino acid sequence of CfSOD shared high identity with cytoplasmic Cu, Zn SOD in molluscs, insects, mammals and other animals, such as cytoplasmic Cu, Zn SOD in oyster Crassostrea gigas (CAD42722), mosquito Aedes aegypti (ABF18094), and cow Bos taurus (XP_584414). A quantitative reverse transcriptase real-time PCR (qRT-PCR) assay was developed to assess the mRNA expression of CfSOD in different tissues and the temporal expression of CfSOD in scallop challenged with Listonella anguillarum, Micrococcus luteus and Candida lipolytica respectively. Higher-level mRNA expression of CfSOD was detected in the tissues of haemocytes, gill filaments and kidney. The expression of CfSOD dropped in the first 8-16 h and then recovered after challenge with L. anguillarum and M. luteus, but no change was induced by the C. lipolytica challenge. The results indicated that CfSOD was a constitutive and inducible acute-phase protein, and could play an important role in the immune responses against L. anguillarum and M. luteus infection. PMID:17574438

  12. Molecular Cloning, Characterization, and Expression of a Catalase Gene in the Japanese Scallop Mizuhopecten yessoensis Induced in the Presence of Cadmium

    NASA Astrophysics Data System (ADS)

    Gao, Jialong; Ishizaki, Shoichiro; Nagashima, Yuji

    2016-03-01

    Cadmium (Cd) is known to influence the oxidative status of marine organisms and can induce the formation of reactive oxygen species (ROS). Catalase (CAT) is one of the important enzymes involved in scavenging high levels of ROS. In present study, we cloned CAT cDNA and investigated the response of this enzyme at the transcriptional level in the Japanese scallop Mizuhopecten yessoensis exposed to Cd. The full-length CAT cDNA (MyCAT) of 1,870 nucleotides including a 57 bp 5'-UTR, a coding sequence of 1,500 bp and a 313 bp 3'-UTR were identified from the scallop. The deduced amino acid sequence of MyCAT corresponds to 499 amino acids with predicted molecular weight of 56.48 kDa and contains highly conserved motifs of the proximal heme-binding site RLFSYSTH, proximal active signature FNRERIPERVVHAKGGG and three catalytic amino acid residues His72, Asn145, and Tyr355. Its significant homology to CATs from multiple alignments revealed that MyCAT had a high identity with CATs from other mollusks. CAT mRNA expression analysis revealed that expression level was highest in the digestive gland ( p < 0.01) but weak in muscle. Following exposure to 200 and 400 µg/l of Cd, a high amount of Cd was found to have accumulated in the digestive gland and CAT mRNA expression had significantly increased in this organ among 7-day exposed scallops ( p < 0.001). The result demonstrated that antioxidant enzymes such as CAT play important roles in counteracting Cd stress in M. yessoensis.

  13. Molecular characterization of two ferritins of the scallop Argopecten purpuratus and gene expressions in association with early development, immune response and growth rate.

    PubMed

    Coba de la Peña, Teodoro; Cárcamo, Claudia B; Díaz, María I; Brokordt, Katherina B; Winkler, Federico M

    2016-08-01

    Ferritin is involved in several iron homoeostasis processes in molluscs. We characterized two ferritin homologues and their expression patterns in association with early development, growth rate and immune response in the scallop Argopecten purpuratus, a species of economic importance for Chile and Peru. Two ferritin subunits (Apfer1 and Apfer2) were cloned. Apfer1 cDNA is a 792bp clone containing a 516bp open reading frame (ORF) that corresponds to a novel ferritin subunit in A. purpuratus. Apfer2 cDNA is a 681bp clone containing a 522bp ORF that corresponds to a previously sequenced EST. A putative iron responsive element (IRE) was identified in the 5'-untranslated region of both genes. The deduced protein sequences of both cDNAs possessed the motifs and domains characteristic of functional ferritin subunits. Both genes showed differential expression patterns at tissue-specific and early development stage levels. Apfer1 expression level increased 40-fold along larval developmental stages, decreasing markedly after larval settlement. Apfer1 expression in mantle tissue was 2.8-fold higher in fast-growing than in slow-growing scallops. Apfer1 increased 8-fold in haemocytes 24h post-challenge with the bacterium Vibrio splendidus. Apfer2 expression did not differ between fast- and slow-growing scallops or in response to bacterial challenge. These results suggest that Apfer1 and Apfer2 may be involved in iron storage, larval development and shell formation. Apfer1 expression may additionally be involved in immune response against bacterial infections and also in growth; and thus would be a potential marker for immune capacity and for fast growth in A. purpuratus. PMID:27040527

  14. Molecular characterization of an inhibitor of NF-κB in the scallop Argopecten purpuratus: First insights into its role on antimicrobial peptide regulation in a mollusk.

    PubMed

    Oyanedel, D; Gonzalez, R; Flores-Herrera, P; Brokordt, K; Rosa, R D; Mercado, L; Schmitt, P

    2016-05-01

    Inhibitors of nuclear factor kappa B (IκBs) are major control components of the Rel/NF-κB signaling pathway, a key regulator in the modulation of the expression of immune-related genes in vertebrates and invertebrates. The activation of the Rel/NF-κB signaling pathway depends largely in the degradation of IκB proteins and thus, IκBs are a main target for the identification of genes whose expression is controlled by Rel/NF-κB pathway. In order to identify such regulation in bivalve mollusks, the cDNA sequence encoding an IκB protein was characterized in the scallop Argopecten purpuratus, ApIκB. The cDNA sequence of ApIκB is comprised of 1480 nucleotides with a 1086 bp open reading frame encoding for 362 amino acids. Bioinformatics analysis showed that ApIκB displays the conserved features of IκB proteins. The deduced amino acid sequence consists of a 39.7 kDa protein, which has an N-terminal degradation motif, six ankyrin repeats and a C-terminal phosphorylation site motif. Phylogenetic analysis revealed a high degree of identity between ApIκB and other IκBs from mollusks, but also to arthropod cactus proteins and vertebrate IκBs. Tissue expression analysis indicated that ApIκB is expressed in all examined tissues and it is upregulated in circulating hemocytes from scallops challenged with the pathogenic Gram-negative bacterium Vibrio splendidus. After inhibiting ApIκB gene expression using the RNA interference technology, the gene expression of the antimicrobial peptide big defensin was upregulated in hemocytes from non-challenged scallops. Results suggest that ApIκB may control the expression of antimicrobial effectors such as big defensin via a putative Rel/NF-κB signaling pathway. This first evidence will help to deepen the knowledge of the Rel/NF-κB conserved pathway in scallops. PMID:26993612

  15. Characterization and pathogenicity of Vibrio splendidus strains associated with massive mortalities of commercial hatchery-reared larvae of scallop Argopecten purpuratus (Lamarck, 1819).

    PubMed

    Rojas, Rodrigo; Miranda, Claudio D; Opazo, Rafael; Romero, Jaime

    2015-01-01

    Three strains (VPAP16, VPAP18 and VPAP23 strains) were isolated as the most predominant organisms from 3 different episodes of massive mortalities of larval cultures of the Chilean scallop Argopecten purpuratus occurred in different commercial hatcheries located in northern Chile. The main aims of this study were to identify the pathogenic strains and investigate their pathogenic activity. Based on selected phenotypic features and sequence identity of the 16S rRNA gene and the housekeeping gene, RNA polymerase α-chain rpoA, all pathogenic strains were identified as Vibrio splendidus. Healthy 10-day-old scallop larvae cultures exhibited mortality percentages of 69.61±3.35%, 79.78±6.11% and 61.73±3.71% after 48 h when were inoculated with 1×10(6) CFU (colony forming units)mL(-1) of VPAP16, VPAP18 and VPAP23 strains, respectively, and evidenced that concentrations ⩾10(4) CFU mL(-1) would probably be detrimental for the larval culture. The main clinical signs observed in challenged larvae for 24h were bacterial swarms on the margins of the larvae, extension and disruption of the velum, detachment of velum cilia cells and digestive tissue necrosis. Otherwise, challenge assays using pathogenic strains stained with 5-([4,6-dichlorotriazin-2-yl]amino)fluorescein hydrochloride (5-DTAF)evidenced that after 1h stained bacteria were detected in high density in the digestive gland and the margin of the shell. When larval cultures were inoculated with cell-free extracellular products (ECP) of V. splendidus strains, exhibited larval mortalities higher than 70% (VPAP16), 80% (VPAP18) and 50% (VPAP23) after 24 h, even when ECP were treated with proteinase K or heat, indicating that extracellular pathogenic activity is mainly mediated by non-proteic thermostable compounds. In this study all Koch's postulates were fulfilled and it was demonstrated for the first time the pathogenic activity of V. splendidus strains on reared-larvae of scallop A. purpuratus and prompt the

  16. Examination of body burden and taint for Iceland scallop (Chlamys islandica) and American plaice (Hippoglossoides platessoides) near the Terra Nova offshore oil development over ten years of drilling on the Grand Banks of Newfoundland, Canada

    NASA Astrophysics Data System (ADS)

    DeBlois, Elisabeth M.; Kiceniuk, Joe W.; Paine, Michael D.; Kilgour, Bruce W.; Tracy, Ellen; Crowley, Roger D.; Williams, Urban P.; Gregory Janes, G.

    2014-12-01

    This paper presents results of analyses of body burdens of metals and hydrocarbons, and taste tests for taint, in Iceland scallop and American plaice performed as part of the Environmental Effects Monitoring (EEM) program for the Terra Nova offshore oil development (Grand Banks of Newfoundland, Canada). Scallop and plaice were collected in a Study Area located within approximately 1 km of drill centres at Terra Nova and in a Reference Area located approximately 20 km from the development. Samples were collected in 1997 to establish a baseline, and from 2000 to 2010, during drilling periods. Scallop adductor muscle tissue was contaminated with >C10-C21 aliphatic hydrocarbons resembling the drilling fluid in the synthetic drilling mud (SBM) used at Terra Nova in 2000, 2002 and 2004, but contamination of adductor muscle was not noted in 2006, 2008 and 2010. The maximum concentration in muscle was 28 mg/kg wet weight, noted in 2002. Scallop viscera was contaminated with hydrocarbons resembling drilling fluid in SBMs near drill centres in all EEM years except 2010. Viscera contamination with >C10-C21 hydrocarbons gradually decreased from a maximum of 150 mg/kg in 2000, to a maximum of 27 mg/kg in 2008; all values were below the laboratory reporting detection limit of 15 mg/kg in 2010. Therefore, evidence from both muscle and viscera indicates a decrease in tissue hydrocarbon contamination in recent years. Barium, another major constituent in drilling muds, has not been noted in scallop adductor muscles at concentrations above the reporting detection limit, but barium was detected in viscera in baseline and EEM years. The maximum concentration of barium in viscera during baseline sampling was 8 mg/kg. The maximum concentration in EEM years (29 mg/kg) was noted in 2000. The maximum concentration in 2010 was 25 mg/kg. The concentration of metals other than barium in scallop tissues was similar between the Terra Nova Study Area and the Reference Area. Hydrocarbons

  17. Early exposure of bay scallops (Argopecten irradians) to high CO₂ causes a decrease in larval shell growth.

    PubMed

    White, Meredith M; McCorkle, Daniel C; Mullineaux, Lauren S; Cohen, Anne L

    2013-01-01

    Ocean acidification, characterized by elevated pCO₂ and the associated decreases in seawater pH and calcium carbonate saturation state (Ω), has a variable impact on the growth and survival of marine invertebrates. Larval stages are thought to be particularly vulnerable to environmental stressors, and negative impacts of ocean acidification have been seen on fertilization as well as on embryonic, larval, and juvenile development and growth of bivalve molluscs. We investigated the effects of high CO₂ exposure (resulting in pH = 7.39, Ω(ar) = 0.74) on the larvae of the bay scallop Argopecten irradians from 12 h to 7 d old, including a switch from high CO₂ to ambient CO₂ conditions (pH = 7.93, Ω(ar) = 2.26) after 3 d, to assess the possibility of persistent effects of early exposure. The survival of larvae in the high CO₂ treatment was consistently lower than the survival of larvae in ambient conditions, and was already significantly lower at 1 d. Likewise, the shell length of larvae in the high CO₂ treatment was significantly smaller than larvae in the ambient conditions throughout the experiment and by 7 d, was reduced by 11.5%. This study also demonstrates that the size effects of short-term exposure to high CO₂ are still detectable after 7 d of larval development; the shells of larvae exposed to high CO₂ for the first 3 d of development and subsequently exposed to ambientCO₂ were not significantly different in size at 3 and 7 d than the shells of larvae exposed to high CO₂ throughout the experiment. PMID:23596514

  18. Early Exposure of Bay Scallops (Argopecten irradians) to High CO2 Causes a Decrease in Larval Shell Growth

    PubMed Central

    White, Meredith M.; McCorkle, Daniel C.; Mullineaux, Lauren S.; Cohen, Anne L.

    2013-01-01

    Ocean acidification, characterized by elevated pCO2 and the associated decreases in seawater pH and calcium carbonate saturation state (Ω), has a variable impact on the growth and survival of marine invertebrates. Larval stages are thought to be particularly vulnerable to environmental stressors, and negative impacts of ocean acidification have been seen on fertilization as well as on embryonic, larval, and juvenile development and growth of bivalve molluscs. We investigated the effects of high CO2 exposure (resulting in pH = 7.39, Ωar = 0.74) on the larvae of the bay scallop Argopecten irradians from 12 h to 7 d old, including a switch from high CO2 to ambient CO2 conditions (pH = 7.93, Ωar = 2.26) after 3 d, to assess the possibility of persistent effects of early exposure. The survival of larvae in the high CO2 treatment was consistently lower than the survival of larvae in ambient conditions, and was already significantly lower at 1 d. Likewise, the shell length of larvae in the high CO2 treatment was significantly smaller than larvae in the ambient conditions throughout the experiment and by 7 d, was reduced by 11.5%. This study also demonstrates that the size effects of short-term exposure to high CO2 are still detectable after 7 d of larval development; the shells of larvae exposed to high CO2 for the first 3 d of development and subsequently exposed to ambient CO2 were not significantly different in size at 3 and 7 d than the shells of larvae exposed to high CO2 throughout the experiment. PMID:23596514

  19. The cation selectivity and voltage dependence of the light-activated potassium conductance in scallop distal photoreceptor.

    PubMed Central

    Cornwall, M C; Gorman, A L

    1983-01-01

    Light-dependent voltage and current responses were measured from the distal hyperpolarizing photoreceptors of the scallop (Pecten irradians) retina. In normal external solution, the hyperpolarizing receptor potential was caused by a light-dependent K+ outward current. The magnitude of the hyperpolarizing receptor potential and the light-dependent outward current, measured at the resting potential, was graded with light intensity. In normal external solution, during prolonged illumination the light-dependent K+ outward current was characterized by an early peak and a subsequent plateau. Current responses to brief light flashes were reduced progressively during background illumination. In the absence of external Na+ ions, the reversal potential for the receptor potential changed 58 mV per 10-fold change in the extracellular K+ concentration. The estimated internal K+ concentration was 385 mM. The hyperpolarizing receptor potential produced by prolonged bright illumination consists of an early peak which decays to a plateau. This decay was determined by a decrease in the light-dependent K+ conductance during maintained illumination. The light-dependent conductance pathway passed outward currents better than inward K+ currents. The light-dependent K+ conductance was estimated to increase e-fold per 23-34 mV depolarization at the peak and during the plateau of the light response. The light-dependent conductance pathway was highly selective for K+ ions. The selectivity sequence for monovalent cations was T1+, K+ greater than Rb+ greater than NH4 greater than Cs+, Li+, Na+. External caesium and tetraethylammonium blocked inward but not outward K+ currents through the light-dependent K+ conductance pathway. The data suggest that K+ ions move through an aqueous pore which is controlled by light. PMID:6887051

  20. An Automatic Procedure for Improving Sea Surface Wind Field Estimation from X-Band COSMO-SkyMed SAR Data

    NASA Astrophysics Data System (ADS)

    Schiavulli, D.; Sorrentino, A.; Nunziata, F.; Montuori, A.; Migliaccio, M.

    2012-03-01

    The Synthetic Aperture Radar (SAR) has been increasingly used as the key sensor for extracting environmental information over the ocean surface and in particular for characterizing a wide range of ocean parameters such as waves, wind, surf and currents. In particular, ScanSAR acquisition mode has been widely employed for sea surface observation due to its peculiarities to provide data with huge swath and low revisit time. In SAR data the study of ocean parameters depend on the atmosphere-sea surface interaction that results in features and imprints appearance, e.g. wind direction retrieval is achievable from the orientation of Atmospheric Boundary Layer (ABL) rolls. Unfortunately, features extraction can be corrupted by the presence of processing artifacts, i.e. scalloping, and atmospheric artifacts that hamper image interpretation. In this paper, an automatic procedure able to perform scalloping suppression and atmospheric fronts analysis over Multi-Look Ground Detected (MGD) ScanSAR HugeRegion X-band Cosmo-SkyMed(CSK) is presented. Experimental results confirm the physical soundness of the proposed model from an operational view point.

  1. Identification and mapping of amplified fragment length polymorphism markers linked to shell color in bay scallop, Argopecten irradians irradians (Lamarck, 1819).

    PubMed

    Qin, Yanjie; Liu, Xiao; Zhang, Haibin; Zhang, Guofan; Guo, Ximing

    2007-01-01

    Amplified fragment length polymorphisms (AFLP) were used to study the inheritance of shell color in Argopecten irradians. Two scallops, one with orange and the other with white shells, were used as parents to produce four F(1) families by selfing and outcrossing. Eighty-eight progeny, 37 orange and 51 white, were randomly selected from one of the families for segregation and mapping analysis with AFLP and microsatellite markers. Twenty-five AFLP primer pairs were screened, yielding 1138 fragments, among which 148 (13.0%) were polymorphic in two parents and segregated in progeny. Six AFLP markers showed significant (P < 0.05) association with shell color. All six loci were mapped to one linkage group. One of the markers, F1f335, is completely linked to the gene for orange shell, which we designated as Orange1, without any recombination in the progeny we sampled. The marker was amplified in the orange parent and all orange progeny, but absent in the white parent and all the white progeny. The close linkage between F1f335 and Orange1 was validated using bulk segregation analysis in two natural populations, and all our data indicate that F1f335 is specific for the shell color gene, Orange1. The genomic mapping of a shell color gene in bay scallop improves our understanding of shell color inheritance and may contribute to the breeding of molluscs with desired shell colors. PMID:17160637

  2. Swimming away or clamming up: the use of phasic and tonic adductor muscles during escape responses varies with shell morphology in scallops.

    PubMed

    Tremblay, Isabelle; Guderley, Helga E; Himmelman, John H

    2012-12-01

    The simple locomotor system of scallops facilitates the study of muscle use during locomotion. We compared five species of scallops with different shell morphologies to see whether shell morphology and muscle use change in parallel or whether muscle use can compensate for morphological constraints. Force recordings during escape responses revealed that the use of tonic and phasic contractions varied markedly among species. The active species, Amusium balloti, Placopecten magellanicus and Pecten fumatus, made more phasic contractions than the more sedentary species, Mimachlamys asperrima and Crassadoma gigantea. Tonic contractions varied considerably among these species, with the two more sedentary species often starting their response to the predator with a tonic contraction and the more active species using shorter tonic contractions between series of phasic contractions. Placopecten magellanicus made extensive use of short tonic contractions. Pecten fumatus mounted an intense series of phasic contractions at the start of its response, perhaps to overcome the constraints of its unfavourable shell morphology. Valve closure by the more sedentary species suggests that their shell morphology protects them against predation, whereas swimming by the more active species relies upon intense phasic contractions together with favourable shell characteristics. PMID:22972884

  3. Exposure to phenanthrene and depuration: Changes on gene transcription, enzymatic activity and lipid peroxidation in gill of scallops Nodipecten nodosus.

    PubMed

    Piazza, Rômi S; Trevisan, Rafael; Flores-Nunes, Fabrício; Toledo-Silva, Guilherme; Wendt, Nestor; Mattos, Jacó J; Lima, Daína; Taniguchi, Satie; Sasaki, Silvio Tarou; Mello, Álvaro C P; Zacchi, Flávia L; Serrano, Miguel A S; Gomes, Carlos H A M; Bícego, Márcia C; Almeida, Eduardo A de; Bainy, Afonso C D

    2016-08-01

    Understanding the mechanism of phenanthrene (PHE) biotransformation and related cellular responses in bivalves can be an important tool to elucidate the risks of polycyclic aromatic hydrocarbons (PAHs) to aquatic organisms. In the present study it was analyzed the transcriptional levels of 13 biotransformation genes related to cytochrome P450 (CYP), glutathione S-transferase (GST), sulfotransferase (SULT), flavin-containing monooxygenase and fatty acid-binding proteins by qPCR in gill of scallops Nodipecten nodosus exposed for 24 or 96h to 50 or 200μgL(-1) PHE (equivalent to 0.28 and 1.12μM, respectively), followed by depuration in clean water for 96h (DEP). Likewise, it was quantified the activity of catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), glutathione reductase (GR), glucose 6-phosphate dehydrogenase (G6PDH), GST and levels of lipid peroxidation. Increased transcriptional levels of CYP2UI-like, CYP2D20-like, CYP3A11-like, GSTomega-like, SULT1B1-like genes were detected in organisms exposed to PHE for 24 or 96h. In parallel, GR and GPX activities increased after 96h exposure to 200μgL(-1) PHE and G6PDH activity increased after 24h exposure to 50μgL(-1) PHE. This enhancement of antioxidant and phase I and II biotransformation systems may be related to the 2.7 and 12.5 fold increases in PHE bioaccumulation after 96h exposure to 50 and 200μgL(-1) PHE, respectively. Interestingly, DEP caused reestablishment of GPX and GR activity, as well as to the transcript levels of all upregulated biotransformation genes (except for SULT1B1-like). Bioaccumulated PHE levels decreased 2.5-2.9 fold after depuration, although some biochemical and molecular modifications were still present. Lipid peroxidation levels remained lower in animals exposed to 200μgL(-1) PHE for 24h and DEP. These data indicate that N. nodosus is able to induce an antioxidant and biotransformation-related response to PHE exposure, counteracting its toxicity, and DEP can

  4. Sea Legs

    NASA Astrophysics Data System (ADS)

    Macdonald, Kenneth C.

    Forty-foot, storm-swept seas, Spitzbergen polar bears roaming vast expanses of Arctic ice, furtive exchanges of forbidden manuscripts in Cold War Moscow, the New York city fashion scene, diving in mini-subs to the sea floor hot srings, life with the astronauts, romance and heartbreak, and invading the last bastions of male exclusivity: all are present in this fast-moving, non-fiction account of one woman' fascinating adventures in the world of marine geology and oceanography.

  5. Spectroscopic and ITC study of the conformational change upon Ca{sup 2+}-binding in TnC C-lobe and TnI peptide complex from Akazara scallop striated muscle

    SciTech Connect

    Yumoto, Fumiaki; Tanaka, Hiroyuki; Nagata, Koji; Miyauchi, Yumiko; Miyakawa, Takuya; Ojima, Takao; Tanokura, Masaru

    2008-04-25

    Akazara scallop (Chlamys nipponensis akazara) troponin C (TnC) of striated adductor muscle binds only one Ca{sup 2+} ion at the C-terminal EF-hand motif (Site IV), but it works as the Ca{sup 2+}-dependent regulator in adductor muscle contraction. In addition, the scallop troponin (Tn) has been thought to regulate muscle contraction via activating mechanisms that involve the region spanning from the TnC C-lobe (C-lobe) binding site to the inhibitory region of the TnI, and no alternative binding of the TnI C-terminal region to TnC because of no similarity between second TnC-binding regions of vertebrate and the scallop TnIs. To clarify the Ca{sup 2+}-regulatory mechanism of muscle contraction by scallop Tn, we have analyzed the Ca{sup 2+}-binding properties of the complex of TnC C-lobe and TnI peptide, and their interaction using isothermal titration microcalorimetry, nuclear magnetic resonance, circular dichroism, and gel filtration chromatography. The results showed that single Ca{sup 2+}-binding to the Site IV leads to a structural transition not only in Site IV but also Site III through the structural network in the C-lobe of scallop TnC. We therefore assumed that the effect of Ca{sup 2+}-binding must lead to a change in the interaction mode between the C-lobe of TnC and the TnI peptide. The change should be the first event of the transmission of Ca{sup 2+} signal to TnI in Tn ternary complex.

  6. A physiologically based toxicokinetic and toxicodynamic model links the tissue distribution of benzo[a]pyrene and toxic effects in the scallop Chlamys farreri.

    PubMed

    Liu, Dong; Pan, Luqing; Yang, Huizan; Wang, Jing

    2014-03-01

    A physiologically based toxicokinetic and toxicodynamic (PBTK-TD) model was developed for benzo[a]pyrene (B[a]P) in scallop Chlamys farreri. The PBTK model structure consisted of gill, digestive gland, adductor muscle, hemolymph and other tissues. In TD modeling, aryl hydrocarbon hydroxylase (AHH) activity assay, comet assay, protein carbonyl measurement and lipid peroxidation level determination in digestive gland were used as biomarkers to reflect toxic effects. We integrated B[a]P concentration and biomarkers by using sigmoid Emax model in digestive gland. The PBTK-TD model predicted the B[a]P concentrations within each organ compartment and the toxic effects in digestive gland. The results showed that the predicted and measured data in different organs were in good agreement and comet assay was considered as the best biomarker. This model would serve as a useful tool for pollution monitoring and food security. PMID:24561533

  7. Genomic in situ hybridization identifies parental chromosomes in hybrid scallop (Bivalvia, Pectinoida, Pectinidae) between female Chlamys farreri and male Argopecten irradians irradians

    PubMed Central

    Huang, Xiaoting; Bi, Ke; Lu, Wei; Wang, Shi; Zhang, Lingling; Bao, Zhenmin

    2015-01-01

    Abstract Interspecific crossing was artificially carried out between Chlamys farreri (Jones & Preston, 1904) ♀ and Argopecten irradians irradians (Lamarck, 1819) ♂, two of the dominant cultivated scallop species in China. Genomic in situ hybridization (GISH) was used to examine the chromosome constitution and variation in hybrids at early embryonic stage. The number of chromosomes in 66.38% of the metaphases was 2n = 35 and the karyotype was 2n = 3 m + 5 sm + 16 st + 11 t. After GISH, two parental genomes were clearly distinguished in hybrids, most of which comprised 19 chromosomes derived from their female parent (Chlamys farreri) and 16 chromosomes from their male parent (Argopecten irradians irradians). Some chromosome elimination and fragmentation was also observed in the hybrids. PMID:26140161

  8. Black Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Black Sea in eastern Russia is experiencing an ongoing phytoplankton bloom. This image, the most recent in a series that began in early may, shows the waters to be even more colorful than before. part of the increased brightness may be due to the presence of sun glint , especially in the center of the sea. However, more organisms appear to be present as well, their photosynthetic pigments reflecting different wavelengths of light.This Moderate Resolution Imaging Spectroradiometer (MODIS) image was captured on June 15, 2002.

  9. Sea Ice

    NASA Technical Reports Server (NTRS)

    Perovich, D.; Gerland, S.; Hendricks, S.; Meier, Walter N.; Nicolaus, M.; Richter-Menge, J.; Tschudi, M.

    2013-01-01

    During 2013, Arctic sea ice extent remained well below normal, but the September 2013 minimum extent was substantially higher than the record-breaking minimum in 2012. Nonetheless, the minimum was still much lower than normal and the long-term trend Arctic September extent is -13.7 per decade relative to the 1981-2010 average. The less extreme conditions this year compared to 2012 were due to cooler temperatures and wind patterns that favored retention of ice through the summer. Sea ice thickness and volume remained near record-low levels, though indications are of slightly thicker ice compared to the record low of 2012.

  10. Aral Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This series of MODIS images shows the dwindling Aral Sea. Once one of the world's largest freshwater lakes, the Aral Sea has decreased by as much as 60% over the past few decades due to diversion of the water to grow cotton and rice. These diversion have dropped the lake levels, increased salinity, and nearly decimated the fishing industry. The previous extent of the lake is clearly visible as a whitish perimeter in these image from April 16, May 18, and June 3, 2002. s. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  11. 76 FR 72891 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition To List the Scalloped Hammerhead...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-28

    ..., delisting, and reclassifying a species under the ESA (61 FR 4722; February 7, 1996). A species, subspecies... overfished stocks within 2 years'' (76 FR 23794; April 28, 2011). This status determination is specific to... in the Atlantic Ocean, including the Caribbean Sea and Gulf of Mexico (76 FR 53652; August 29,...

  12. Ross Sea

    Atmospheric Science Data Center

    2013-04-16

    article title:  Icebergs in the Ross Sea     View Larger Image Two large icebergs, designated B-15A and C-16, are captured in this Multi-angle Imaging ... the longitudinal quadrant in which it is first seen, and new icebergs sighted in that quadrant are sequentially numbered. B-15 divided from ...

  13. From Sea to Shining Sea

    ERIC Educational Resources Information Center

    Scott, Beverly

    2005-01-01

    Deep down in the depths of the sea, beautiful fish, mysterious ocean life, and unusual plants glimmer and glow in the eerie atmosphere of an ever-changing ocean. This article describes how, with this vision and a purpose in mind, three teachers pulled open classroom walls and joined forces so their second graders could create a mammoth 30 x 75"…

  14. Animals of the Seas and Wetlands. Alaska Sea Week Curriculum Series II. Alaska Sea Grant Report 85-11.

    ERIC Educational Resources Information Center

    Mickelson, Belle

    This curriculum guide is the second (Series II) in a six-volume set that comprises the Sea Week Curriculum Series developed in Alaska. This second book in the series lends itself to the first-grade level but can be adapted to preschool, secondary, and adult education. Nine units contain 30 activities with worksheets that cover the following…

  15. Sea Ice

    NASA Technical Reports Server (NTRS)

    Parkinson, Claire L.; Cavalieri, Donald J.

    2005-01-01

    Sea ice covers vast areas of the polar oceans, with ice extent in the Northern Hemisphere ranging from approximately 7 x 10(exp 6) sq km in September to approximately 15 x 10(exp 6) sq km in March and ice extent in the Southern Hemisphere ranging from approximately 3 x 10(exp 6) sq km in February to approximately 18 x 10(exp 6) sq km in September. These ice covers have major impacts on the atmosphere, oceans, and ecosystems of the polar regions, and so as changes occur in them there are potential widespread consequences. Satellite data reveal considerable interannual variability in both polar sea ice covers, and many studies suggest possible connections between the ice and various oscillations within the climate system, such as the Arctic Oscillation, North Atlantic Oscillation, and Antarctic Oscillation, or Southern Annular Mode. Nonetheless, statistically significant long-term trends are also apparent, including overall trends of decreased ice coverage in the Arctic and increased ice coverage in the Antarctic from late 1978 through the end of 2003, with the Antarctic ice increases following marked decreases in the Antarctic ice during the 1970s. For a detailed picture of the seasonally varying ice cover at the start of the 21st century, this chapter includes ice concentration maps for each month of 2001 for both the Arctic and the Antarctic, as well as an overview of what the satellite record has revealed about the two polar ice covers from the 1970s through 2003.

  16. Mammals of the Sea.

    ERIC Educational Resources Information Center

    Naturescope, 1986

    1986-01-01

    Presents information on sea mammals, including definitions and characteristics of cetaceans, pinnipeds, and sirenians. Contains descriptions of the teaching activities "Whale Music,""Draw A Whale to Scale,""Adopt a Sea Mammal," and "Sea Mammal Sleuths." (TW)

  17. Melting Ice, Rising Seas

    NASA Video Gallery

    Sea level rise is an indicator that our planet is warming. Much of the world's population lives on or near the coast, and rising seas are something worth watching. Sea level can rise for two reason...

  18. Adult Compacts.

    ERIC Educational Resources Information Center

    Further Education Unit, London (England).

    This bulletin focuses on adult compacts, three-way agreements among employers, potential employees, and trainers to provide the right kind of quality training to meet the employers' requirements. Part 1 is an executive summary of a report of the Adult Compacts Project, which studied three adult compacts in Birmingham and Loughborough, England, and…

  19. Pycnogonids associated with the giant lion´s-paw scallop Nodipecten subnodosus (Sowerby) in Ojo de Liebre Bay, Guerrero Negro, Baja California Sur, Mexico

    PubMed Central

    de León-Espinosa, Angel; de León-González, Jesus A.

    2015-01-01

    Abstract Five species of epibenthic pycnogonids collected on the giant lion´s-paw scallop Nodipecten subnodosus are recorded. A new species of Eurycyde, Eurycyde bamberi, is described. Of the 19 species known in this genus; the new species is closest to Eurycyde hispida Kroyer, 1844 but differs from it in the absence of plumose spines and the shapes of the lateral process, first coxa, and ocular tubercle. The new species represents the third member of Eurycyde from the eastern Pacific in addition to Eurycyde spinosa Hilton, 1916 and Eurycyde clitellaria Stock, 1955. Besides Eurycyde bamberi, the following species were collected: Nymphopsis duodorsospinosa Hilton, 1942c; Callipallene californiensis (Hall, 1913); Nymphon lituus Child, 1979; and Pycnogonum rickettsi Schmitt, 1934. Pycnogonum rickettsi is recorded for first time from Mexican waters, as is Nymphon lituus from the western coast of Baja California Peninsula. Each of these four species are re-described and re-illustrated in order to fill in existing gaps in the literature of the region. PMID:26692802

  20. Pycnogonids associated with the giant lion´s-paw scallop Nodipecten subnodosus (Sowerby) in Ojo de Liebre Bay, Guerrero Negro, Baja California Sur, Mexico.

    PubMed

    de León-Espinosa, Angel; de León-González, Jesus A

    2015-01-01

    Five species of epibenthic pycnogonids collected on the giant lion´s-paw scallop Nodipecten subnodosus are recorded. A new species of Eurycyde, Eurycyde bamberi, is described. Of the 19 species known in this genus; the new species is closest to Eurycyde hispida Kroyer, 1844 but differs from it in the absence of plumose spines and the shapes of the lateral process, first coxa, and ocular tubercle. The new species represents the third member of Eurycyde from the eastern Pacific in addition to Eurycyde spinosa Hilton, 1916 and Eurycyde clitellaria Stock, 1955. Besides Eurycyde bamberi, the following species were collected: Nymphopsis duodorsospinosa Hilton, 1942c; Callipallene californiensis (Hall, 1913); Nymphon lituus Child, 1979; and Pycnogonum rickettsi Schmitt, 1934. Pycnogonum rickettsi is recorded for first time from Mexican waters, as is Nymphon lituus from the western coast of Baja California Peninsula. Each of these four species are re-described and re-illustrated in order to fill in existing gaps in the literature of the region. PMID:26692802

  1. Colorful Underwater Sea Creatures

    ERIC Educational Resources Information Center

    McCutcheon, Heather

    2011-01-01

    In this article, the author describes a project wherein students created colorful underwater sea creatures. This project began with a discussion about underwater sea creatures and how they live. The first step was making the multi-colored tissue paper that would become sea creatures and seaweed. Once students had the shapes of their sea creatures…

  2. Beaufort Sea: information update

    SciTech Connect

    Becker, P.R.

    1988-04-01

    The report is based on a multi-disciplinary meeting held March 6-7, 1985, as part of preparations for the Beaufort Sea Sale 97. The chapters are based on presentations given: The causeway effect: Modification of nearshore thermal regime resulting from causeways; Summertime sea ice intrusions in the Chukchi Sea; The deepwater limit of ice gouging on the Beaufort Sea shelf; Distribution, abundance, migration, harvest, and stock identity of Belukha Whales in the Beaufort Sea; Ringed seals in the Beaufort Sea; Beaufort Sea socioeconomics; The Baffin Island Oil Spill, (BIOS) Project.

  3. Discovery: An Introduction. Alaska Sea Week Curriculum Series. Alaska Sea Grant Report 83-6.

    ERIC Educational Resources Information Center

    Mickelson, Belle; And Others

    This curriculum guide is the first (Series I) in a six-volume set that comprises the Sea Week Curriculum Series developed in Alaska. As a basic introduction, this first book in the series lends itself to the kindergarten level but can be adapted to preschool, secondary, and adult education. Six units contain 32 activities with worksheets that…

  4. Fish and Fisheries. Alaska Sea Week Curriculum Series VI. Alaska Sea Grant Report 83-7.

    ERIC Educational Resources Information Center

    Mickelson, Belle; Barr, Nancy

    This curriculum guide is the fifth (Series VI) in a six-volume set that comprises the Sea Week Curriculum Series developed in Alaska. The book lends itself to the fifth-grade level but can be adapted to preschool, secondary, and adult education. Seven units contain 48 activities with worksheets that cover the following topics: (1) fish, their…

  5. Shells and Insects. Alaska Sea Week Curriculum Series III. Alaska Sea Grant Report 84-4.

    ERIC Educational Resources Information Center

    Kelsey, Claudia; And Others

    This curriculum guide is the third (Series III) in a six-volume set that comprises the Sea Week Curriculum Series developed in Alaska. The book lends itself to the second-grade level but can be adapted to preschool, secondary, and adult education. Ten units contain 77 activities with worksheets that cover the following topics: (1) introduction to…

  6. In vitro study of the effect of metabolism enzymes on benzo(a)pyrene-induced DNA damage in the scallop Chlamys farreri.

    PubMed

    Cai, Yuefeng; Pan, Luqing; Miao, Jingjing

    2016-03-01

    Acute toxicity effect of benzo(a)pyrene (BaP) on isolated scallop (Chlamys farreri) digestive gland cells was studied and a dose-dependent increase in toxicity was observed. The 8μg/L of BaP had a significant toxic effect on isolated cells (p<0.05). In order to study the mechanism of CYP450, GST, SOD and MXR transporters involved in the production of DNA strand breakage such as DNA adduct formation and oxidative DNA damage by BaP were investigated in isolated digestive gland cells. Isolated cells were exposed in vitro to 0.8μg/L of BaP for 24h in the dark at 25°C in the absence or presence of cytochrome P450 inhibitor, GST inhibitor, Pgp inhibitor and antioxidant enzyme inhibitor. DNA adduct and 8-OHdG content were measured using the Enzyme-linked Immunosorbent Assay. The result indicated that DNA strand breakage was increased to 2 times compared with the control in the 0.8μg/L of BaP treatment groups. The BaP-induced DNA adduct and 8-OHdG content increased significantly by inhibiting GST, while only 8-OHdG increased significantly when SOD was inhibited. The content of DNA adduct and 8-OHdG had no significant change when CYP450 was inhibited, while it decreased significantly when MXR transporters were inhibited. The result proved that GST play a key role in eliminating the BaP-induced DNA adduct and 8-OHdG, and SOD also had an important function in reducing the production of BaP-induced 8-OHdG. PMID:26851374

  7. Learning & Knowledge Production in North Carolina Sea Turtle Conservation Communities of Practice

    ERIC Educational Resources Information Center

    Martin, Kathleen Carol

    2010-01-01

    This dissertation focused upon non-formal and informal learning practices and knowledge production amongst [adult] participants involved in local sea turtle conservation practices along the US Atlantic coast. In the United States, adult learning and adult education has historically occurred within non-formal settings (e.g., through community-based…

  8. Urinary tract infection - adults

    MedlinePlus

    Bladder infection - adults; UTI - adults; Cystitis - bacterial - adults; Pyelonephritis - adults; Kidney infection - adults ... to the hospital if you: Are an older adult Have kidney stones or changes in the anatomy ...

  9. 50 CFR 648.58 - Rotational Closed Areas.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Atlantic Sea Scallop Fishery § 648.58 Rotational Closed Areas. (a) Elephant Trunk Closed Area. No vessel may fish for scallops in, or possess or land scallops from, the area known as the Elephant Trunk Closed Area. No vessel may possess scallops in the Elephant Trunk Closed Area, unless such vessel is...

  10. Sea urchin granuloma.

    PubMed

    Rossetto, André Luiz; de Macedo Mora, Jamesson; Haddad Junior, Vidal

    2006-01-01

    Injuries caused by venomous and poisonous aquatic animals may provoke important morbidity in humans. The phylum Echinoderma include more than 6000 species of starfish, sea urchins, sand dollars, and sea cucumbers some of which have been found responsible for injuries to humans. Initial injuries by sea urchins are associated with trauma and envenomation, but later effects can be observed. Sea urchin granuloma is a chronic granulomatous skin disease caused by frequent and successive penetration of sea urchin spines which have not been removed from wounds. The authors report a typical case of sea urchin granuloma in a fisherman and its therapeutic implications. PMID:17086323

  11. Aral Sea basin: a sea dies, a sea also rises.

    PubMed

    Glantz, Michael H

    2007-06-01

    The thesis of this article is quite different from many other theses of papers, books, and articles on the Aral Sea. It is meant to purposely highlight the reality of the situation in Central Asia: the Aral Sea that was once a thriving body of water is no more. That sea is dead. What does exist in its place are the Aral seas: there are in essence three bodies of water, one of which is being purposefully restored and its level is rising (the Little Aral), and two others which are still marginally connected, although they continue to decline in level (the Big Aral West and the Big Aral East). In 1960 the level of the sea was about 53 m above sea level. By 2006 the level had dropped by 23 m to 30 m above sea level. This was not a scenario generated by a computer model. It was a process of environmental degradation played out in real life in a matter of a few decades, primarily as a result of human activities. Despite wishes and words to the contrary, it will take a heroic global effort to save what remains of the Big Aral. It would also take a significant degree of sacrifice by people and governments in the region to restore the Big Aral to an acceptable level, given that the annual rate of flow reaching the Amudarya River delta is less than a 10th of what it was several decades ago. Conferring World Heritage status to the Aral Sea(s) could spark restoration efforts for the Big Aral. PMID:17626470

  12. Sea ice transports in the Weddell Sea

    NASA Astrophysics Data System (ADS)

    Harms, Sabine; Fahrbach, Eberhard; Strass, Volker H.

    2001-05-01

    Time series of sea ice draft in the Weddell Sea are evaluated together with hydrographic observations, satellite passive microwave data, and ice drift for estimation of the freshwater fluxes into and out of the Weddell Sea. Ice draft is measured with moored upward looking sonars since 1990 along two transects across the Weddell Gyre. One transect, extending from the tip of the Antarctic Peninsula to Kapp Norvegia, was sampled between 1990 and 1994 and covers the flow into and out of the southern Weddell Sea. The other transect, sampled since 1996 and extending from the Antarctic continent northward along the Greenwich meridian, covers the exchange of water masses between the eastern and the western Weddell Sea. In order to relate results obtained during the different time periods, empirical relationships are established between the length of the sea ice season, derived from the satellite passive microwave data and defined as the number of days per year with the sea ice concentration exceeding 15%, and (1) the annual mean ice draft and (2) the annual mean ice volume transport. By using these empirical relationships, estimates of annual mean ice drafts and ice volume transports are derived at all mooring sites for the period February 1979 through February 1999. Wind and current force a westward ice transport in the coastal areas of the eastern Weddell Sea and a northward ice transport in the west. During the 2-year period 1991/1992 the mean ice volume export from the Weddell Sea is (50 ± 19) × 103 m3 s-1. This freshwater export is representative for a longer-term (20-year) mean and exceeds the average amount of freshwater gained by precipitation and ice shelf melt by about 19×103 m3 s-1, yielding an upper bound for the formation rate of newly ventilated bottom water in the Weddell Sea of 2.6 Sv.

  13. All That Unplowed Sea

    ERIC Educational Resources Information Center

    MOSAIC, 1975

    1975-01-01

    Hunting and gathering at sea may fast be approaching their productive limits. Aquaculture - farming at sea - linked to conservation represents the sea's promise. If the system works, it might prove to be the key to supplying large amounts of food and fresh water at no cost in nonrenewable energy resources. (BT)

  14. Adult Strabismus

    MedlinePlus

    ... will likely improve the double vision and depth perception. Also, strabismus affects adults in emotional, social, and ... muscle surgery is usually not severe. Headache, pulling sensation with eye movement and foreign body sensation in ...

  15. 50 CFR 648.51 - Gear and crew restrictions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Measures for the Atlantic Sea Scallop Fishery § 648.51 Gear and crew restrictions. (a) Trawl vessel gear... diamond mesh. (3) Minimum ring size. (i) Unless otherwise required under the Sea Scallop Area Access...) Restrictions applicable to sea scallop dredges in the mid-Atlantic—(i) Requirement to use chain mats. See §...

  16. Bartonella spp. Exposure in Northern and Southern Sea Otters in Alaska and California

    PubMed Central

    Chomel, Bruno B.; Gill, Verena A.; Doroff, Angela M.; Miller, Melissa A.; Burek-Huntington, Kathleen A.; Kasten, Rickie W.; Byrne, Barbara A.; Goldstein, Tracey; Mazet, Jonna A.K.

    2014-01-01

    Abstract Since 2002, an increased number of northern sea otters (Enhydra lutris kenyoni) from southcentral Alaska have been reported to be dying due to endocarditis and/or septicemia with infection by Streptococcus infantarius subsp. coli. Bartonella spp. DNA was also detected in northern sea otters as part of mortality investigations during this unusual mortality event (UME) in Kachemak Bay, Alaska. To evaluate the extent of exposure to Bartonella spp. in sea otters, sera collected from necropsied and live-captured northern sea otters, as well as necropsied southern sea otters (Enhydra lutris nereis) unaffected by the UME, were analyzed using an immunofluorescent antibody assay. Antibodies against Bartonella spp. were detected in sera from 50% of necropsied and 34% of presumed healthy, live-captured northern sea otters and in 16% of necropsied southern sea otters. The majority of sea otters with reactive sera were seropositive for B. washoensis, with antibody titers ranging from 1:64 to 1:256. Bartonella spp. antibodies were especially common in adult northern sea otters, both free-living (49%) and necropsied (62%). Adult stranded northern sea otters that died from infectious causes, such as opportunistic bacterial infections, were 27 times more likely to be Bartonella seropositive than adult stranded northern sea otters that died from noninfectious causes (p<0.001; 95% confidence interval 2.62–269.4). Because Bartonella spp. antibodies were detected in necropsied northern sea otters from southcentral (44%) and southwestern (86%) stocks of Alaska, as well as in necropsied southern sea otters (16%) in southcentral California, we concluded that Bartonella spp. exposure is widely distributed among sea otter populations in the Eastern Pacific, providing context for investigating future disease outbreaks and monitoring of Bartonella infections for sea otter management and conservation. PMID:25514118

  17. Bartonella spp. exposure in northern and southern sea otters in Alaska and California.

    PubMed

    Carrasco, Sebastian E; Chomel, Bruno B; Gill, Verena A; Doroff, Angela M; Miller, Melissa A; Burek-Huntington, Kathleen A; Kasten, Rickie W; Byrne, Barbara A; Goldstein, Tracey; Mazet, Jonna A K

    2014-12-01

    Since 2002, an increased number of northern sea otters (Enhydra lutris kenyoni) from southcentral Alaska have been reported to be dying due to endocarditis and/or septicemia with infection by Streptococcus infantarius subsp. coli. Bartonella spp. DNA was also detected in northern sea otters as part of mortality investigations during this unusual mortality event (UME) in Kachemak Bay, Alaska. To evaluate the extent of exposure to Bartonella spp. in sea otters, sera collected from necropsied and live-captured northern sea otters, as well as necropsied southern sea otters (Enhydra lutris nereis) unaffected by the UME, were analyzed using an immunofluorescent antibody assay. Antibodies against Bartonella spp. were detected in sera from 50% of necropsied and 34% of presumed healthy, live-captured northern sea otters and in 16% of necropsied southern sea otters. The majority of sea otters with reactive sera were seropositive for B. washoensis, with antibody titers ranging from 1:64 to 1:256. Bartonella spp. antibodies were especially common in adult northern sea otters, both free-living (49%) and necropsied (62%). Adult stranded northern sea otters that died from infectious causes, such as opportunistic bacterial infections, were 27 times more likely to be Bartonella seropositive than adult stranded northern sea otters that died from noninfectious causes (p<0.001; 95% confidence interval 2.62-269.4). Because Bartonella spp. antibodies were detected in necropsied northern sea otters from southcentral (44%) and southwestern (86%) stocks of Alaska, as well as in necropsied southern sea otters (16%) in southcentral California, we concluded that Bartonella spp. exposure is widely distributed among sea otter populations in the Eastern Pacific, providing context for investigating future disease outbreaks and monitoring of Bartonella infections for sea otter management and conservation. PMID:25514118

  18. Chemosterilization of the sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Hanson, Lee H.; Manion, Patrick J.

    1978-01-01

    The chemical, P,P-bis(1-aziridinyl)-N-methylphosphinothioic amide (bisazir), was found in laboratory studies to be an effective sterilant for both sexes of adult sea lampreys (Petromyzon marinus) when given intraperitoneally at a dosage of 100 mg per kilogram of body weight. A total of 300 normal spawning-run sea lampreys and 300 injected with bisazir were released into the Big Garlic River, Marquette County, Michigan, (a small stream divided into five sections by natural barriers), to determine the effect of bisazir on the nesting and spawning behavior of the adults and on the production of larvae. The lampreys constructed and spawned in 95 nests. Sterile adults showed no abnormal nest building or spawning behavior. Sterile males competed effectively with normal males for females. Egg samples taken from nests indicated that eggs in nests where sterile males spawned with sterile or normal females did not hatch, although some embryonic development occurred. Extensive surveys with electric shockers produced no larvae in stream sections where sterile males spawned, but yielded numerous larvae in sections where normal males spawned with normal females. These findings suggest that the release of sterile males may be an effective tool in an integrated approach to control of sea lampreys in the Great Lakes.

  19. Obstructive sleep apnea - adults

    MedlinePlus

    Sleep apnea - obstructive - adults; Apnea - obstructive sleep apnea syndrome - adults; Sleep-disordered breathing - adults; OSA - adults ... the upper airway for obstructive sleep apnea in adults. Sleep . 2010;33:1408-1413. PMID: 21061864 www. ...

  20. Regional sea level variability in the Bohai Sea, Yellow Sea, and East China Sea

    NASA Astrophysics Data System (ADS)

    Cheng, Yongcun; Plag, Hans-Peter; Hamlington, Benjamin D.; Xu, Qing; He, Yijun

    2015-12-01

    The regional sea level variability in the Bohai Sea (BS), Yellow Sea (YS) and East China Sea (ECS) is investigated based on tide gauge, satellite altimeter data and an independent oceanic general circulation model for the Earth Simulator (OFES) model outputs. It is found that atmospheric forcing significantly affects local sea level variability in the BS and YS and local sea level variability at the Southern ECS is highly correlated with along-shore currents. Particularly, the annual sea level fluctuations potentially change inundation risk and the frequency and magnitude of flooding in regions with high annual sea level. Hence, the cyclostationary empirical orthogonal function (CSEOF) analysis is carried out to investigate the variations of annual sea level cycle amplitude. Similar spatial distribution characteristics of annual sea level amplitude fluctuations are presented from satellite altimeter data and model outputs. The variability of annual sea level amplitude estimated from the satellite altimeter data agrees well with that from the tide gauge data, and positively (negatively) correlates with Southern Oscillation Index (Pacific Decadal Oscillation). The OFES model, however, underestimates the fluctuation of the annual cycle. After removing the annual signal, the low-passed (i.e., 13-month running mean) tide gauge data shows high correlations with SOI and PDO on time scales over 8 years in the BS and ECS.

  1. Dust Storm, Aral Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Aral Sea has shrunk to less than half its size since 1985. The Aral Sea receives little water (sometimes no water) from the two major rivers that empty into it-the Syr Darya and Amu Darya. Instead, the river water is diverted to support irrigation for the region's extensive cotton fields. Recently, water scarcity has increased due to a prolonged drought in Central Asia. As the Aral Sea recedes, its former sea bed is exposed. The Aral's sea bed is composed of fine sediments-including fertilizers and other agricultural chemicals-that are easily picked up by the region's strong winds, creating thick dust storms. The International Space Station crew observed and recorded a large dust storm blowing eastward from the Aral Sea in late June 2001. This image illustrates the strong coupling between human activities (water diversions and irrigation), and rapidly changing land, sea and atmospheric processes-the winds blow across the

  2. Hydrodynamics of a Digitized Adult Humpback Whale Flipper

    NASA Astrophysics Data System (ADS)

    Fassmann, Wesley N.; McDonald, Samuel J.; Thomson, Scott L.; Fish, Frank E.

    2013-11-01

    During feeding, humpback whales turn with a turn radius of up to 1 /6th of their length towards schools of fish enclosed by bubble nets. This high maneuverability requirement is facilitated by high aspect ratio flippers with leading edge tubercles that delay stall. Previous experimental and computational studies have used idealized models, such as airfoils with scalloped leading edges, to explore the influence of leading edge tubercles on boundary layer separation, vortex generation, and airfoil lift and drag characteristics. Owing to the substantial size of the flipper, no studies have been performed on a digitized adult humpback flipper with real geometry. In this study the hydrodynamics of a realistic humpback flipper model were explored. The model was developed by digitizing a sequence of 18 images circumscribing the suspended flipper of a beached humpback whale. A physical prototype was constructed based on the resulting 3D model, along with a complementary model with the tubercles removed. Experimentally-obtained measurements of lift and drag were used to study the influence of the tubercles. In the presentation, digitization and flow measurement methods are described, and the flow data and results are presented and discussed.

  3. Adult Play.

    ERIC Educational Resources Information Center

    Charles, John M.

    In its broadest context, play can be interpreted as any pleasurable use of discretionary time. Playfulness is an intrinsic feature of being human, and should be viewed in the light of a total lifestyle, not as an occurrence in an isolated time of life. Adult play appears to be an indefinable and controversial concept. A holistic approach should be…

  4. CPR: Adult

    MedlinePlus Videos and Cool Tools

    Refresher Center Home FIRST AID, CPR and AED LIFEGUARDING Refresher Putting It All Together: CPR—Adult (2:03) Refresher videos only utilize this player QUICK LINKS Home RedCross.org Purchase Course Materials Shop Our Store ...

  5. East Siberian Sea, Russia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The winter sea ice in the east Siberian Sea is looking a bit like a cracked windshield in these true-color Moderate Resolution Imaging Spectroradiometer (MODIS) images from June 16 and 23, 2002. North of the thawing tundra, the sea ice takes on its cracked, bright blue appearance as it thins, which allows the reflection of the water to show through. Numerous still-frozen lakes dot the tundra. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  6. Studying Recombination with High-Throughput Sequencing: An Educational Primer for Use with “Fine-Scale Heterogeneity in Crossover Rate in the garnet-scalloped Region of the Drosophila melanogaster X chromosome”

    PubMed Central

    Heil, Caiti S. Smukowski; Noor, Mohamed A. F.

    2013-01-01

    An article by Singh and colleagues in this issue of GENETICS quantifies variation in recombination rate across a small region of the Drosophila melanogaster genome, providing an opportunity for instructors of genetics to introduce or reinforce important concepts such as recombination and recombination rate variation, genome sequencing, and sequence features of the genome. Additional background information, a detailed explanation of the methods used in this study, and discussion questions are provided. Related article in GENETICS: Singh, N. D., E. A. Stone, C. F. Aquadro, and A. G. Clark, 2013 Fine-scale heterogeneity in crossover rate in the garnet-scalloped region of the Drosophila melanogaster X chromosome. Genetics 194: 375–387. PMID:23733850

  7. Performance Characteristics of AOAC Method 2005.06 for the Determination of Paralytic Shellfish Toxins in Manila Clams, European Otter Clams, Grooved Carpet Shell Clams, Surf Clams, and Processed King Scallops.

    PubMed

    O'Neill, Alison; Turner, Andrew D

    2015-01-01

    An approach was developed for the verification of method performance of the AOAC 2005.06 LC-fluorescence detector (FLD) method for determination of paralytic shellfish poisoning (PSP) toxins in bivalve shellfish. This was developed following advice published by the Analytical Laboratory Accreditation Criteria Committee and applied to shellfish species that had not been previously subjected to a full single-laboratory validation scheme. The refined approach was developed following the need to assess performance in a number of shellfish species infrequently monitored through the UK statutory monitoring program, while reducing the impact and cost of the studies, most notably in terms of the use of valuable reference standards. The species assessed were manila clams (Ruditapes philippinarum), European otter clams (Lutraria lutraria), grooved carpet shell clams (R. decussatus), surf clams (Spisula solida), and king scallops (Pecten maximus) presented as adductor only or adductor plus roe. The method was assessed for sensitivity in terms of LOD and LOQ, toxin recovery, and method precision in each species. It incorporated the PSP toxins deemed toxic and/or prevalent in UK samples and commercially available as certified reference standards. The toxins studied included GTX1-5, dcSTX, STX, C1&2, and NEO. The toxins dcGTX2&3 were included for surf clams due to the prevalence of these toxins in this species as a result of toxin decarbamoylation. Method performance targets were met for each of the characteristics investigated. Consequently, the method was deemed fit for purpose for the screening and quantification of these clam and scallop species for PSP toxins by AOAC Method 2005.06 LC-FLD. PMID:26024751

  8. ADULT EDUCATION OF MIGRANT ADULTS.

    ERIC Educational Resources Information Center

    BEAL, CATHERINE; AND OTHERS

    UNITS ON MIGRANT ADULT EDUCATION, AND A UNIT ON ORGANIZING INFORMAL GROUPS OF MIGRANT WOMEN TO DISCUSS MAINTAINING AND IMPROVING THEIR TEMPORARY HOMES, ARE PRESENTED. THE GOALS OF THE UNIT ON EDUCATION FOR MIGRANT MEN ARE ECONOMIC INDEPENDENCE, BETTER HEALTH AND WELL-BEING, AND BETTER HANDLING OF RESPONSIBILITIES. THE MAIN DIVISIONS OF THE…

  9. Damage sustained by epibenthic invertebrates discarded in the Nephrops fishery of the Clyde Sea area, Scotland

    NASA Astrophysics Data System (ADS)

    Bergmann, M.; Beare, D. J.; Moore, P. G.

    2001-05-01

    The Clyde Sea Nephrops fishery produces ca. 25 000 t y -1 discards with invertebrates accounting for up to 90% of the number of animals discarded. Trawling and handling of the (by-)catch often results in physical injury, the extent of which was previously unknown. Damage sustained by invertebrate discards was assessed following commercial trawling (of 62-270 min duration) and sorting on deck. Brittlestars Ophiura ophiura were most vulnerable with 100% incurring damage, followed by squat lobsters Munida rugosa (57%) and starfish Astropecten irregularis (56%). Harder-shelled species such as hermit crabs Pagurus bernhardus and queen scallops Aequipecten opercularis sustained fewer injuries (14 and 2%, respectively). Shell chipping, loss and damage of limbs were the most frequent types of injury incurred. The severity and frequency of damage was mainly correlated with species-specific morphological and behavioural characteristics. Vessel type, tow duration and animal size had a major influence on damage to the epibenthic invertebrates caught. While damage may potentially be repaired, survival is adversely affected and sublethal effects might significantly impair fitness of frequently trawled individuals and populations.

  10. Coccolithophorids in the Bering Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This clear SeaWiFS image shows the bright blooms of coccolithophores in the Bering Sea off the coast of Alaska.. Credit: Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  11. [Adult twins].

    PubMed

    Charlemaine, Christiane

    2006-12-31

    This paper explores the deep roots of closeness that twins share in their youngest age and their effect on their destiny at the adult age. Psychologists believe the bond between twins begins in utero and develops throughout the twins' lives. The four patterns of twinship described show that the twin bond is determined by the quality of parenting that twins receive in their infancy and early childhood. Common problems of adult twins bring about difficulties to adapt in a non-twin world. The nature versus nurture controversy has taken on new life focusing on inter-twin differences and the importance of parent-child interaction as fundamental to the growth and development of personality. PMID:17352324

  12. Obstructive sleep apnea - adults

    MedlinePlus

    Sleep apnea - obstructive - adults; Apnea - obstructive sleep apnea syndrome - adults; Sleep-disordered breathing - adults; OSA - adults ... When you sleep, all of the muscles in your body become more relaxed. This includes the muscles that help keep your ...

  13. Sea Anemone: Investigations.

    ERIC Educational Resources Information Center

    Hunt, John D.

    1982-01-01

    Several investigations can be undertaken with live sea anemones. A sea anemone's feeding response, fighting power, color, and symbiotic relationships to other invertebrates (such as a marine hermit crab) can be investigated in the high school classroom. Background information and laboratory procedures are provided. (Author/JN)

  14. Getting Your Sea Legs

    PubMed Central

    Stoffregen, Thomas A.; Chen, Fu-Chen; Varlet, Manuel; Alcantara, Cristina; Bardy, Benoît G.

    2013-01-01

    Sea travel mandates changes in the control of the body. The process by which we adapt bodily control to life at sea is known as getting one's sea legs. We conducted the first experimental study of bodily control as maritime novices adapted to motion of a ship at sea. We evaluated postural activity (stance width, stance angle, and the kinematics of body sway) before and during a sea voyage. In addition, we evaluated the role of the visible horizon in the control of body sway. Finally, we related data on postural activity to two subjective experiences that are associated with sea travel; seasickness, and mal de debarquement. Our results revealed rapid changes in postural activity among novices at sea. Before the beginning of the voyage, the temporal dynamics of body sway differed among participants as a function of their (subsequent) severity of seasickness. Body sway measured at sea differed among participants as a function of their (subsequent) experience of mal de debarquement. We discuss implications of these results for general theories of the perception and control of bodily orientation, for the etiology of motion sickness, and for general phenomena of perceptual-motor adaptation and learning. PMID:23840560

  15. White Sea - Russia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    At bottom center of this true-color Moderate Resolution Imaging Spectroradiometer (MODIS) image from April 13, 2001, the White Sea in western Russia is becoming free of ice in its southern extent. Meanwhile, the blue-green waters along the coast of the peninsula jutting out into the Barents Sea to the northeast could be due to a phytoplankton bloom.

  16. Black Sea in Bloom

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This true-color image shows bright, turquoise-colored swirls across the surface of the Black Sea, signifying the presence of a large phytoplankton bloom. Scientists have observed similar blooms recurring annually, roughly this same time of year. The Sea of Azov, which is the smaller body of water located just north of the Black Sea in this image, also shows a high level of biological activity currently ongoing. The brownish pixels in the Azov are probably sediments carried in from high waters upstream. This scene was acquired by the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), flying aboard the OrbView-2 satellite, on May 4, 2002. According to the Black Sea Environment Programme's Marine Hydrophysical Institute, the Black Sea is 'one of the marine areas of the world most damaged by human activities.' The coastal zone around these Eastern European inland water bodies is densely populated-supporting a permanent population of roughly 16 million people and another 4 million tourists each year. Six countries border with the Black Sea, including Ukraine to the north, Russia and Georgia to the east, Turkey to the south, and Bulgaria and Romania to the west. Because it is isolated from the world's oceans, and because there is an extensive drainage network of rivers that empty into it, the Black Sea has a unique and delicate water balance which is very important for supporting its marine ecosystem. Of particular concern to scientists is the salinity, water level, and nutrient levels of the Black Sea's waters, all of which are, unfortunately, being impacted by human activities. Within the last three decades the combination of increased nutrient loads from human sources together with pollution and over-harvesting of fisheries has resulted in a sharp decline in water quality. Scientists from each of the Black Sea's bordering nations are currently working together to study the issues and formulate a joint, international strategy for saving this unique marine ecosystem

  17. Survival and breeding of polar bears in the southern Beaufort Sea in relation to sea ice

    USGS Publications Warehouse

    Regehr, E.V.; Hunter, C.M.; Caswell, H.; Amstrup, Steven C.; Stirling, I.

    2010-01-01

    1. Observed and predicted declines in Arctic sea ice have raised concerns about marine mammals. In May 2008, the US Fish and Wildlife Service listed polar bears (Ursus maritimus) - one of the most ice-dependent marine mammals - as threatened under the US Endangered Species Act. 2. We evaluated the effects of sea ice conditions on vital rates (survival and breeding probabilities) for polar bears in the southern Beaufort Sea. Although sea ice declines in this and other regions of the polar basin have been among the greatest in the Arctic, to date population-level effects of sea ice loss on polar bears have only been identified in western Hudson Bay, near the southern limit of the species' range. 3. We estimated vital rates using multistate capture-recapture models that classified individuals by sex, age and reproductive category. We used multimodel inference to evaluate a range of statistical models, all of which were structurally based on the polar bear life cycle. We estimated parameters by model averaging, and developed a parametric bootstrap procedure to quantify parameter uncertainty. 4. In the most supported models, polar bear survival declined with an increasing number of days per year that waters over the continental shelf were ice free. In 2001-2003, the ice-free period was relatively short (mean 101 days) and adult female survival was high (0 ∙ 96-0 ∙ 99, depending on reproductive state). In 2004 and 2005, the ice-free period was longer (mean 135 days) and adult female survival was low (0 ∙ 73-0 ∙ 79, depending on reproductive state). Breeding rates and cub litter survival also declined with increasing duration of the ice-free period. Confidence intervals on vital rate estimates were wide. 5. The effects of sea ice loss on polar bears in the southern Beaufort Sea may apply to polar bear populations in other portions of the polar basin that have similar sea ice dynamics and have experienced similar, or more severe, sea ice declines. Our findings

  18. Survival and breeding of polar bears in the southern Beaufort Sea in relation to sea ice.

    PubMed

    Regehr, Eric V; Hunter, Christine M; Caswell, Hal; Amstrup, Steven C; Stirling, Ian

    2010-01-01

    1. Observed and predicted declines in Arctic sea ice have raised concerns about marine mammals. In May 2008, the US Fish and Wildlife Service listed polar bears (Ursus maritimus) - one of the most ice-dependent marine mammals - as threatened under the US Endangered Species Act. 2. We evaluated the effects of sea ice conditions on vital rates (survival and breeding probabilities) for polar bears in the southern Beaufort Sea. Although sea ice declines in this and other regions of the polar basin have been among the greatest in the Arctic, to date population-level effects of sea ice loss on polar bears have only been identified in western Hudson Bay, near the southern limit of the species' range. 3. We estimated vital rates using multistate capture-recapture models that classified individuals by sex, age and reproductive category. We used multimodel inference to evaluate a range of statistical models, all of which were structurally based on the polar bear life cycle. We estimated parameters by model averaging, and developed a parametric bootstrap procedure to quantify parameter uncertainty. 4. In the most supported models, polar bear survival declined with an increasing number of days per year that waters over the continental shelf were ice free. In 2001-2003, the ice-free period was relatively short (mean 101 days) and adult female survival was high (0.96-0.99, depending on reproductive state). In 2004 and 2005, the ice-free period was longer (mean 135 days) and adult female survival was low (0.73-0.79, depending on reproductive state). Breeding rates and cub litter survival also declined with increasing duration of the ice-free period. Confidence intervals on vital rate estimates were wide. 5. The effects of sea ice loss on polar bears in the southern Beaufort Sea may apply to polar bear populations in other portions of the polar basin that have similar sea ice dynamics and have experienced similar, or more severe, sea ice declines. Our findings therefore are

  19. Marine Mammals, Coastal and River Issues. Alaska Sea Week Curriculum Series VII. Alaska Sea Grant Report 84-8.

    ERIC Educational Resources Information Center

    Mickelson, Belle

    This curriculum guide is the last (Series VII) in a six-volume set that comprises the Sea Week Curriculum Series developed in Alaska. The guide lends itself to the sixth-grade curriculum but can be adapted to preschool, secondary, and adult education. Eight units contain 43 activities with worksheets that cover the following topics: (1) the values…

  20. Analysis of the November 1999 Dead Sea Calibration Shots

    SciTech Connect

    Rodgers, A J; Myers, S; Mayeda, K; Walter, W

    2000-07-21

    In November 1999 three chemical explosions were conducted in the Dead Sea for the purposes of calibrating the International Monitoring System (IMS) for the Comprehensive Nuclear-Test-Ban Treaty (CTBT). These shots were organized and conducted by the Geophysical Institute of Israel (GII). Large chemical explosions are the most valuable form of ground truth as the location, depth and origin time are very well known. We focus on the two largest shots (M{sub w} {ge} 3.6) and performed several types of analysis of the regional recordings and travel times of these shots. These data provide valuable new information about the region and offer an opportunity to test monitoring strategies. A crustal and uppermost mantle velocity model was inferred from the travel times of the regional phases: Pn, Pg and Sg. This effort utilized a grid search method to find suitable models of the structure. Results indicate that the crust is relatively thin (32 km) with lower than average crustal velocities (mean V{sub P} = 6.1-6.2 km/s). We located each shot treating the other shot as a calibration explosion. Locations were computed using both station static corrections and kriged correction surfaces. Results show that the locations with static corrections can be better or worse than the locations without corrections. However, the locations with kriged correction surfaces are consistently better than those without corrections or with static corrections because kriging properly accounts for residual statistics. Measures of the S-wave coda for regional events provide a stable estimate of event size (moment magnitude, M{sub w}) and the event source spectrum. S-wave coda envelope amplitudes were calibrated to moments estimated from long-period waveform modeling. We measured moment and body-wave magnitudes and source spectra for many events in the region. The Dead Sea shots show spectral peaking associated with shallow events. Finally, analysis of regional broadband recordings from the Saudi

  1. Adult Development and Learning of Older Adults

    ERIC Educational Resources Information Center

    Roberson, Donald N., Jr.

    2005-01-01

    This summary of adult development covers a wide range of authors. Adult development is one way of understanding how the internal and external changes in our lives have an impact on learning. Of particular importance in this work are the developmental issues of older adults. I present various theories of adult development such as linear and…

  2. 50 CFR 648.1 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Salmon FMP); the Atlantic sea scallop fishery (Scallop FMP); the Atlantic surf clam and ocean quahog fisheries (Atlantic Surf Clam and Ocean Quahog FMP); the NE multispecies and monkfish fisheries...

  3. Global sea level rise

    SciTech Connect

    Douglas, B.C. )

    1991-04-15

    Published values for the long-term, global mean sea level rise determined from tide gauge records exhibit considerable scatter, from about 1 mm to 3 mm/yr. This disparity is not attributable to instrument error; long-term trends computed at adjacent sites often agree to within a few tenths of a millimeter per year. Instead, the differing estimates of global sea level rise appear to be in large part due to authors' using data from gauges located at convergent tectonic plate boundaries, where changes of land elevation give fictitious sea level trends. In addition, virtually all gauges undergo subsidence or uplift due to postglacial rebound (PGR) from the last deglaciation at a rate comparable to or greater than the secular rise of sea level. Modeling PGR by the ICE-3G model of Tushingham and Peltier (1991) and avoiding tide gauge records in areas of converging tectonic plates produces a highly consistent set of long sea level records. The value for mean sea level rise obtained from a global set of 21 such stations in nine oceanic regions with an average record length of 76 years during the period 1880-1980 is 1.8 mm/yr {plus minus} 0.1. This result provides confidence that carefully selected long tide gauge records measure the same underlying trend of sea level and that many old tide gauge records are of very high quality.

  4. Evidence that sea lampreys (Petromyzon marinus) complete their life cycle within a tributary of the Laurentian Great Lakes by parasitizing fishes in inland lakes

    USGS Publications Warehouse

    Johnson, Nicholas; Twohey, Michael B.; Miehls, Scott M.; Cwalinski, Tim A; Godby, Neal A; Lochet, Aude; Slade, Jeffrey W.; Jubar, Aaron K.; Siefkes, Michael J.

    2015-01-01

    The sea lamprey (Petromyzon marinus) invaded the upper Laurentian Great Lakes and feeds on valued fish. The Cheboygan River, Michigan, USA, is a large sea lamprey producing tributary to Lake Huron and despite having a renovated dam 2 km from the river mouth that presumably blocks sea lamprey spawning migrations, the watershed upstream of the dam remains infested with larval sea lamprey. A navigational lock near the dam has been hypothesized as the means of escapement of adult sea lampreys from Lake Huron and source of the upper river population (H1). However, an alternative hypothesis (H2) is that some sea lampreys complete their life cycle upstream of the dam, without entering Lake Huron. To evaluate the alternative hypothesis, we gathered angler reports of lamprey wounds on game fishes upstream of the dam, and captured adult sea lampreys downstream and upstream of the dam to contrast abundance, run timing, size, and statolith microchemistry. Results indicate that a small population of adult sea lampreys (n < 200) completed their life cycle upstream of the dam during 2013 and 2014. This is the most comprehensive evidence that sea lampreys complete their life history within a tributary of the upper Great Lakes, and indicates that similar landlocked populations could occur in other watersheds. Because the adult sea lamprey population upstream of the dam is small, complete elimination of the already low adult escapement from Lake Huron might allow multiple control tactics such as lampricides, trapping, and sterile male release to eradicate the population.

  5. Polar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline.

    PubMed

    Bromaghin, Jeffrey F; Mcdonald, Trent L; Stirling, Ian; Derocher, Andrew E; Richardson, Evan S; Regehr, Eric V; Douglas, David C; Durner, George M; Atwood, Todd; Amstrup, Steven C

    2015-04-01

    In the southern Beaufort Sea of the United States and Canada, prior investigations have linked declines in summer sea ice to reduced physical condition, growth, and survival of polar bears (Ursus maritimus). Combined with projections of population decline due to continued climate warming and the ensuing loss of sea ice habitat, those findings contributed to the 2008 decision to list the species as threatened under the U.S. Endangered Species Act. Here, we used mark-recapture models to investigate the population dynamics of polar bears in the southern Beaufort Sea from 2001 to 2010, years during which the spatial and temporal extent of summer sea ice generally declined. Low survival from 2004 through 2006 led to a 25-50% decline in abundance. We hypothesize that low survival during this period resulted from (1) unfavorable ice conditions that limited access to prey during multiple seasons; and possibly, (2) low prey abundance. For reasons that are not clear, survival of adults and cubs began to improve in 2007 and abundance was comparatively stable from 2008 to 2010, with ~900 bears in 2010 (90% CI 606-1212). However, survival of subadult bears declined throughout the entire period. Reduced spatial and temporal availability of sea ice is expected to increasingly force population dynamics of polar bears as the climate continues to warm. However, in the short term, our findings suggest that factors other than sea ice can influence survival. A refined understanding of the ecological mechanisms underlying polar bear population dynamics is necessary to improve projections of their future status and facilitate development of management strategies. PMID:26214910

  6. Polar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline

    USGS Publications Warehouse

    Bromaghin, Jeffrey F.; McDonald, Trent L.; Stirling, Ian; Derocher, Andrew E.; Richardson, Evan S.; Regehr, Eric V.; Douglas, David C.; Durner, George M.; Atwood, Todd C.; Amstrup, Steven C.

    2015-01-01

    In the southern Beaufort Sea of the United States and Canada, prior investigations have linked declines in summer sea ice to reduced physical condition, growth, and survival of polar bears (Ursus maritimus). Combined with projections of population decline due to continued climate warming and the ensuing loss of sea ice habitat, those findings contributed to the 2008 decision to list the species as threatened under the U.S. Endangered Species Act. Here, we used mark–recapture models to investigate the population dynamics of polar bears in the southern Beaufort Sea from 2001 to 2010, years during which the spatial and temporal extent of summer sea ice generally declined. Low survival from 2004 through 2006 led to a 25–50% decline in abundance. We hypothesize that low survival during this period resulted from (1) unfavorable ice conditions that limited access to prey during multiple seasons; and possibly, (2) low prey abundance. For reasons that are not clear, survival of adults and cubs began to improve in 2007 and abundance was comparatively stable from 2008 to 2010, with ~900 bears in 2010 (90% CI 606–1212). However, survival of subadult bears declined throughout the entire period. Reduced spatial and temporal availability of sea ice is expected to increasingly force population dynamics of polar bears as the climate continues to warm. However, in the short term, our findings suggest that factors other than sea ice can influence survival. A refined understanding of the ecological mechanisms underlying polar bear population dynamics is necessary to improve projections of their future status and facilitate development of management strategies.

  7. PCB concentrations and activity of sea lamprey Petromyzon marinus vary by sex

    USGS Publications Warehouse

    Madenjian, Charles P.; Johnson, Nicholas S.; Binder, Thomas R.; Rediske, Richard R.; O'Keefe, James P.

    2013-01-01

    We determined the polychlorinated biphenyl (PCB) concentrations of 40 male and 40 female adult sea lampreys Petromyzon marinus captured in the Cheboygan River, a tributary to Lake Huron, during May 2011. In addition, we performed a laboratory experiment using passive integrated transponder tags to determine whether male adult sea lampreys were more active than female adult sea lampreys. Sex had a significant effect on PCB concentration, and PCB concentration at a given level of sea lamprey condition was approximately 25 % greater in males than in females. Adjusting for the difference in condition between the sexes, males averaged a 17 % greater PCB concentration compared with females. Results from the laboratory experiment indicated that males were significantly more active than females. The observed sex difference in PCB concentrations was not due to female sea lampreys releasing eggs at spawning because the sea lamprey is semelparous, and we caught the sea lampreys before spawning. Rather, we attributed the sex difference in PCB concentrations to a greater rate of energy expenditure in males compared with females. We proposed that this greater rate of energy expenditure was likely due to greater activity. Our laboratory experiment results supported this hypothesis. A greater resting metabolic rate may also have contributed to a greater rate of energy expenditure. Our findings should eventually be applicable toward improving control of sea lamprey, a pest responsible for considerable damage to fisheries in lakes where it is not native.

  8. Sea Perch Project

    NASA Technical Reports Server (NTRS)

    2010-01-01

    David Lalejini, an employee of the Naval Research Laboratory at NASA's John C. Stennis Space Center, helps a pair of teachers deploy a remotely-operated underwater Sea Perch robot during workshop activities Dec. 11. The Stennis Education Office teamed with Naval Research Laboratory counterparts to conduct a two-day workshop Dec. 10-11 for Louisiana and Mississippi teachers. During the no-cost workshop, teachers learned to build and operate Sea Perch robots. The teachers now can take the Sea Perch Program back to students.

  9. Sea level variation

    NASA Technical Reports Server (NTRS)

    Douglas, Bruce C.

    1992-01-01

    Published values for the long-term, global mean sea level rise determined from tide gauge records range from about one to three mm per year. The scatter of the estimates appears to arise largely from the use of data from gauges located at convergent tectonic plate boundaries where changes of land elevation give fictitious sea level trends, and the effects of large interdecadal and longer sea level variations on short (less than 50+ years) or sappy records. In addition, virtually all gauges undergo subsidence or uplift due to isostatic rebound from the last deglaciation at a rate comparable to or greater than the secular rise of sea level. Modeling rebound by the ICE-3G model of Tushingham and Peltier (1990) and avoiding tide gauge records in areas of converging tectonic plates produces a highly consistent set of long sea level records. A global set of 21 such stations in nine oceanic regions with an average record length of 76 years during the period 1880-1980 yields the global sea level rise value 1.8 mm/year +/- 0.1. Greenhouse warming scenarios commonly forecast an additional acceleration of global sea level in the next 5 or 6+ decades in the range 0.1-0.2 mm/yr2. Because of the large power at low frequencies in the sea level spectrum, very long tide gauge records (75 years minimum) have been examined for past apparent sea level acceleration. For the 80-year period 1905-1985, 23 essentially complete tide gauge records in 10 geographic groups are available for analysis. These yielded the apparent global acceleration -0.011 (+/- 0.012) mm/yr2. A larger, less uniform set of 37 records in the same 10 groups with 92 years average length covering the 141 years from 1850-1991 gave 0.001 (+/- 0.008) mm/yr2. Thus there is no evidence for an apparent acceleration in the past 100+ years that is significant either statistically, or in comparison to values associated with global warming. Unfortunately, the large interdecadal fluctuations of sea level severely affect

  10. 2011 Sea Ice Minimum

    NASA Video Gallery

    This video shows Arctic sea ice from March 7, 2011, to Sept. 9, 2011, ending with a comparison of the 30-year average minimum extent, shown in yellow, and the Northwest Passage, in red. (no audio) ...

  11. 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.

  12. Sea level change

    SciTech Connect

    Meier, M.F.

    1996-12-31

    The IPCC (Intergovernmental Panel on Climate Change) 1995 Scientific Assessment, Chapter 7. Sea Level Change, presents a modest revision of the similar chapter in the 1990 Assessment. Principal conclusions on observed sea-level change and the principal terms in the sea-level equation (ocean thermal expansion, glaciers, ice sheets, and land hydrology), including our knowledge of the present-day (defined as the 20th Century) components of sea-level rise, and projections of these for the future, are presented here. Some of the interesting glaciological problems which are involved in these studies are discussed in more detail. The emphasis here is on trends over decades to a century, not on shorter variations nor on those of the geologic past. Unfortunately, some of the IPCC projections had not been agreed at the time of writing of this paper, and these projections will not be given here. 15 refs., 2 figs.

  13. Teacher at Sea.

    ERIC Educational Resources Information Center

    Beighley, Karl

    1998-01-01

    Outlines the experiences of a teacher in the National Oceanic and Atmospheric Administration's (NOAA) Teacher At Sea Program in which teachers are placed on NOAA vessels to work with professional scientists doing critical, real world research. (DDR)

  14. Dead Sea Scrolls

    NASA Technical Reports Server (NTRS)

    1994-01-01

    A consortium of researchers from Jet Propulsion Laboratory and three other organizations used charged coupled devices (CCDs) and other imaging enhancement technology to decipher previously unreadable portions of the Dead Sea Scrolls. The technique has potentially important implications for archeology.

  15. Sea Raiders of Acadia

    ERIC Educational Resources Information Center

    Dickason, Olive Patricia

    1976-01-01

    One of the French allies, the Micmac, waged much of the war against the English on the sea. This article discusses the determined stand by the Micmac seamen of the eastern coasts for their lands and way of life. (NQ)

  16. Sea ice ecosystems.

    PubMed

    Arrigo, Kevin R

    2014-01-01

    Polar sea ice is one of the largest ecosystems on Earth. The liquid brine fraction of the ice matrix is home to a diverse array of organisms, ranging from tiny archaea to larger fish and invertebrates. These organisms can tolerate high brine salinity and low temperature but do best when conditions are milder. Thriving ice algal communities, generally dominated by diatoms, live at the ice/water interface and in recently flooded surface and interior layers, especially during spring, when temperatures begin to rise. Although protists dominate the sea ice biomass, heterotrophic bacteria are also abundant. The sea ice ecosystem provides food for a host of animals, with crustaceans being the most conspicuous. Uneaten organic matter from the ice sinks through the water column and feeds benthic ecosystems. As sea ice extent declines, ice algae likely contribute a shrinking fraction of the total amount of organic matter produced in polar waters. PMID:24015900

  17. Science at Sea.

    ERIC Educational Resources Information Center

    Phillips, Mary Nied

    2001-01-01

    Describes a three-week inservice teacher education program that involves two sessions of preparatory classes ashore in nautical science and oceanography, and concludes with a nine-day sea voyage. (ASK)

  18. Record Sea Ice Minimum

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Arctic sea ice reached a record low in September 2007, below the previous record set in 2005 and substantially below the long-term average. This image shows the Arctic as observed by the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) aboard NASA's Aqua satellite on September 16, 2007. In this image, blue indicates open water, white indicates high sea ice concentration, and turquoise indicates loosely packed sea ice. The black circle at the North Pole results from an absence of data as the satellite does not make observations that far north. Three contour lines appear on this image. The red line is the 2007 minimum, as of September 15, about the same time the record low was reached, and it almost exactly fits the sea ice observed by AMSR-E. The green line indicates the 2005 minimum, the previous record low. The yellow line indicates the median minimum from 1979 to 2000.

  19. Mediterranean sea level variations.

    NASA Astrophysics Data System (ADS)

    Vigo, I.; Sánchez Reales, J. M.; García, D.; Chao, B. F.

    2009-04-01

    In this work we report an updated study of the sea level variations for the Mediterranean sea for the period from October 1992 to January 2008. The study addresses two mayor issues: (i)The analysis of the spatial and temporal variability of sea surface height (SSH) from radar altimetry measurements (from TOPEX/Poseidon (T/P) + Jason-1, etc.). We use EOF analysis to explain most of its interannual variation, and how the different basins interact. (ii) The analysis of dynamics and balance of water mass transport for the whole period. We estimate the steric SSH by combining the steric SSH estimated from temperature and salt profiles simulated by the ECCO model with time-variable gravity (TVG) data (from GRACE) for the Mediterranean Sea. The estimated steric SSH together with the SSH obtained from altimetry allow for a more realistic estimation of the water mass variations in the Mediterranean for the whole period.

  20. A Sea Experience.

    ERIC Educational Resources Information Center

    Glickstein, Neil

    1989-01-01

    Described is a teacher education program organized by the Sea Education Association in Woods Hole (Massachusetts). The experience, including activities and examples of studies conducted, is discussed. Contact information for future cruises is included. (CW)

  1. South China Sea.

    PubMed

    Morton, B; Blackmore, G

    2001-12-01

    The South China Sea is poorly understood in terms of its marine biota, ecology and the human impacts upon it. What is known is most often contained in reports and workshop and conference documents that are not available to the wider scientific community. The South China Sea has an area of some 3.3 million km2 and depths range from the shallowest coastal fringe to 5377 m in the Manila Trench. It is also studded with numerous islets, atolls and reefs many of which are just awash at low tide. It is largely confined within the Tropic of Cancer and, therefore, experiences a monsoonal climate being influenced by the Southwest Monsoon in summer and the Northeast Monsoon in winter. The South China Sea is a marginal sea and, therefore, largely surrounded by land. Countries that have a major influence on and claims to the sea include China, Malaysia, the Philippines and Vietnam, although Thailand, Indonesia and Taiwan have some too. The coastal fringes of the South China Sea are home to about 270 million people that have had some of the fastest developing and most vibrant economies on the globe. Consequently, anthropogenic impacts, such as over-exploitation of resources and pollution, are anticipated to be huge although, in reality, relatively little is known about them. The Indo-West Pacific biogeographic province, at the centre of which the South China Sea lies, is probably the world's most diverse shallow-water marine area. Of three major nearshore habitat types, i.e., coral reefs, mangroves and seagrasses, 45 mangrove species out of a global total of 51, most of the currently recognised 70 coral genera and 20 of 50 known seagrass species have been recorded from the South China Sea. The island groups of the South China Sea are all disputed and sovereignty is claimed over them by a number of countries. Conflicts have in recent decades arisen over them because of perceived national rights. It is perhaps because of this that so little research has been undertaken on the

  2. Black Sea Becomes Turquoise

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This true-color image shows bright, turquoise-colored swirls across the surface of the Black Sea, signifying the presence of a large phytoplankton bloom. Scientists have observed similar blooms recurring annually, roughly this same time of year. The Sea of Azov, which is the smaller body of water located just north of the Black Sea in this image, also shows a high level of color variance. The brownish pixels in the Azov are probably due to sediments carried in from high waters and snowmelt from upstream. This scene was acquired by the Moderate Resolution Imaging Spectroradiometer, flying aboard NASA's Terra satellite, on May 14, 2002. According to the Black Sea Environment Programme's Marine Hydrophysical Institute, the Black Sea is ?one of the marine areas of the world most damaged by human activities.? The coastal zone around these Eastern European inland water bodies is densely populated'supporting a permanent population of roughly 16 million people and another 4 million tourists each year. Six countries border with the Black Sea, including Ukraine to the north, Russia and Georgia to the east, Turkey to the south, and Bulgaria and Romania to the west. Because it is isolated from the world's oceans, and because there is an extensive drainage network of rivers that empty into it, the Black Sea has a unique and delicate water balance which is very important for supporting its marine ecosystem. Of particular concern to scientists is the salinity, water level, and nutrient levels of the Black Sea's waters, all of which are, unfortunately, being impacted by human activities. Within the last three decades the combination of increased nutrient loads from human sources together with pollution and over-harvesting of fisheries has resulted in a sharp decline in water quality. Scientists from each of the Black Sea's bordering nations are currently working together to study the issues and formulate a joint, international strategy for saving this unique marine ecosystem

  3. Contemporary sea level rise.

    PubMed

    Cazenave, Anny; Llovel, William

    2010-01-01

    Measuring sea level change and understanding its causes has considerably improved in the recent years, essentially because new in situ and remote sensing observations have become available. Here we report on most recent results on contemporary sea level rise. We first present sea level observations from tide gauges over the twentieth century and from satellite altimetry since the early 1990s. We next discuss the most recent progress made in quantifying the processes causing sea level change on timescales ranging from years to decades, i.e., thermal expansion of the oceans, land ice mass loss, and land water-storage change. We show that for the 1993-2007 time span, the sum of climate-related contributions (2.85 +/- 0.35 mm year(-1)) is only slightly less than altimetry-based sea level rise (3.3 +/- 0.4 mm year(-1)): approximately 30% of the observed rate of rise is due to ocean thermal expansion and approximately 55% results from land ice melt. Recent acceleration in glacier melting and ice mass loss from the ice sheets increases the latter contribution up to 80% for the past five years. We also review the main causes of regional variability in sea level trends: The dominant contribution results from nonuniform changes in ocean thermal expansion. PMID:21141661

  4. Analysis of sea level and sea surface temperature changes in the Black Sea

    NASA Astrophysics Data System (ADS)

    Betul Avsar, Nevin; Jin, Shuanggen; Kutoglu, Hakan; Erol, Bihter

    2016-07-01

    The Black Sea is a nearly closed sea with limited interaction with the Mediterranean Sea through the Turkish Straits. Measurement of sea level change will provide constraints on the water mass balance and thermal expansion of seawaters in response to climate change. In this paper, sea level changes in the Black Sea are investigated between January 1993 and December 2014 using multi-mission satellite altimetry data and sea surface temperature (SST) data. Here, the daily Maps of Sea Level Anomaly (MSLA) gridded with a 1/8°x1/8° spatial resolution from AVISO and the NOAA 1/4° daily Optimum Interpolation Sea Surface Temperature (OISST) Anomaly data set are used. The annual cycles of sea level and sea surface temperature changes reach the maximum values in November and January, respectively. The trend is 3.16±0.77 mm/yr for sea level change and -0.06±0.01°C/yr for sea surface temperature during the same 22-year period. The observed sea level rise is highly correlated with sea surface warming for the same time periods. In addition, the geographical distribution of the rates of the Black Sea level and SST changes between January 1993 and December 2014 are further analyzed, showing a good agreement in the eastern Black Sea. The rates of sea level rise and sea surface warming are larger in the eastern part than in the western part except in the northwestern Black Sea. Finally, the temporal correlation between sea level and SST time series are presented based on the Empirical Orthogonal Function (EOF) analysis.

  5. Projecting future sea level

    USGS Publications Warehouse

    Cayan, Daniel R.; Bromirski, Peter; Hayhoe, Katharine; Tyree, Mary; Dettinger, Mike; Flick, Reinhard

    2006-01-01

    California’s coastal observations and global model projections indicate that California’s open coast and estuaries will experience increasing sea levels over the next century. Sea level rise has affected much of the coast of California, including the Southern California coast, the Central California open coast, and the San Francisco Bay and upper estuary. These trends, quantified from a small set of California tide gages, have ranged from 10–20 centimeters (cm) (3.9–7.9 inches) per century, quite similar to that estimated for global mean sea level. So far, there is little evidence that the rate of rise has accelerated, and the rate of rise at California tide gages has actually flattened since 1980, but projections suggest substantial sea level rise may occur over the next century. Climate change simulations project a substantial rate of global sea level rise over the next century due to thermal expansion as the oceans warm and runoff from melting land-based snow and ice accelerates. Sea level rise projected from the models increases with the amount of warming. Relative to sea levels in 2000, by the 2070–2099 period, sea level rise projections range from 11–54 cm (4.3–21 in) for simulations following the lower (B1) greenhouse gas (GHG) emissions scenario, from 14–61 cm (5.5–24 in) for the middle-upper (A2) emission scenario, and from 17–72 cm (6.7–28 in) for the highest (A1fi) scenario. In addition to relatively steady secular trends, sea levels along the California coast undergo shorter period variability above or below predicted tide levels and changes associated with long-term trends. These variations are caused by weather events and by seasonal to decadal climate fluctuations over the Pacific Ocean that in turn affect the Pacific coast. Highest coastal sea levels have occurred when winter storms and Pacific climate disturbances, such as El Niño, have coincided with high astronomical tides. This study considers a range of projected future

  6. Annual sea ice. An air-sea gas exchange moderator

    SciTech Connect

    Gosink, T.A.; Kelley, J.J.

    1982-01-01

    Arctic annual sea ice, particularly when it is relatively warm (> -15/sup 0/C) permits significant gas exchange between the sea and air throughout the entire year. Sea ice, particularly annual sea ice, differs from freshwater ice with respect to its permeability to gases. The presence of brine allows for significant air-sea-ice exchange of CO/sub 2/ throughout the winter, which may significantly affect the global carbon dioxide balance. Other trace gases are also noted to be enriched in sea ice, but less is known about their importance to air-sea-interactions at this time. Both physical and biological factors cause and modify evolution of gases from the surface of sea ice. Quantitative and qualitative descriptions of the nature and physical behavior of sea ice with respect to brine and gases are discussed.

  7. Changes in extreme sea levels in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Dieterich, Christian; Gröger, Matthias; Andersson, Helén; Nerheim, Signild; Jönsson, Anette

    2016-04-01

    A newly developed shallow water model for the Baltic Sea and North Sea is presented. The model is validated by means of a comparison with hindcast simulations with observational data sets. The aim of the development is to provide and apply a modelling tool to model extreme sea levels in the Baltic Sea, Kattegat and Skagerrak. The model approach will support the direct analysis of extreme sea level observations in the past and provide the possibility to extend the statistical data base by producing very long time series or very large ensembles of coastal sea levels. This effort is intended to contribute to an assessment of risks due to storm surges and coastal flooding in the 21st century along the coast of Sweden. By using different RCP climate scenarios downscaled with a regional, coupled climate model atmospheric forcing is available to project possible changes in extreme sea levels into the future. Projected sea level rise, changes in dynamical sea level in the North East Atlantic and tidal forcing in the northern North Sea are applied as boundary condition which allows to investigate their impact on the dynamics of regional sea level variability. Initial experiments focus on the impact of model resolution, resolution in the atmospheric forcing and the amount of details necessary in the bathymetry to faithfully model coastal sea level in the Baltic Sea and North Sea.

  8. The White Sea, Russia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Editor's Note: The caption below, published on May 10, 2001, is incorrect. According to Masha Vorontsova, director of the International Fund for Animal Welfare in Moscow, the situation with the seal pups in the White Sea is normal. There is no disaster and there never was. For more details, refer to the article entitled 'No Danger' on the New Scientist home page. The Earth Observatory regrets the earlier errant report. Original Caption According to the Russian Polar Research Institute for Fisheries and Oceanography, between 250,000 and 300,000 Greenland seal pups face death by starvation over the next two months due to a cruel trick by mother nature. The seals, most of them less than two months old, are trapped on ice sheets that remain locked in the White Sea, located near Archangel in Northern Russia. Typically, during the spring thaw the ice sheets break up and flow with the currents northward into the Barents Sea, the seals' spring feeding grounds. The seal pups hitch a ride on the ice floes, living on their own individual stores of fat until they arrive in the Barents Sea. Their mothers departed for the Barents Sea weeks ago. In a normal year, the seal pups' trip from the White Sea out to the Barents takes about six weeks and the seals have adapted to rely upon this mechanism of mother nature. During their yearly migration, the mother seals usually stay with their pups and feed them until their pelts turn from white to grey--a sign that the pups are mature enough to swim and feed themselves. Unfortunately, this year unusually strong northerly winds created a bottleneck of ice near the mouth of the white sea, thus blocking the flow of ice and trapping the pups. These true-color images of the White Sea were acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. This image, taken May 2, 2000 that there is usually much less ice in the White Sea this time of year as most of it is typically en route to the

  9. Adults Need Vaccines, Too!

    MedlinePlus

    ... turn JavaScript on. Feature: Adult Vaccinations Adults Need Vaccines, Too! Past Issues / Summer 2015 Table of Contents ... of the millions of adults not receiving the vaccines you need? What vaccines do you need? All ...

  10. Adult Still's disease

    MedlinePlus

    Still's disease - adult; AOSD ... than 1 out of 100,000 people develop adult-onset Still's disease each year. It affects women more often than men. The cause of adult Still's disease is unknown. No risk factors for ...

  11. Brain tumor - primary - adults

    MedlinePlus

    ... Vestibular schwannoma (acoustic neuroma) - adults; Meningioma - adults; Cancer - brain tumor (adults) ... Primary brain tumors include any tumor that starts in the brain. Primary brain tumors can start from brain cells, ...

  12. Sea otter studies in Glacier Bay National Park and Preserve: annual report 2002

    USGS Publications Warehouse

    Bodkin, James L.; Kloecker, Kimberly A.; Esslinger, George G.; Monson, Daniel H.; Coletti, Heather A.; Doherty, Janet

    2003-01-01

    Glacier Bay prior to occupation and foraging by sea otters. Port Althorp sites were chosen to achieve a representative sample of subtidal clam beds already under prolonged foraging pressure by sea otters. There was no direct evidence of otter foraging at any of our Glacier Bay sampling sites. In Glacier Bay, we sampled 15,338 bivalves (average of 1,180/site) representing 14 species of clam, 2 species of mussel, and a single scallop and we sampled 6,917 urchins (average of 513/site). In Port Althorp, we sampled 1,034 bivalves (average of 207/site) representing 14 species of clam. We found only 5 urchins, all S. droebachiensis. Mean densities and biomass of all subtidal clams were significantly greater in Glacier Bay (59.2 and 99/0.25m2 compared to Port Althorp (10.3 and 5.8/0.25m2 (p Our contrasts of subtidal clam populations between Glacier Bay and Port Althorp suggest that clam densities will likely decline by about a factor of six and that clam biomass estimates will decline by more than a factor of ten. Numerically dominant species of clams, P. staminea, S. gigantea, Macoma sp. and Mya sp. were all significantly greater in density and biomass in Glacier Bay, while C. nutalli density was low but significantly higher in Port Althorp. Subtidal clam species diversity was significantly greater in Port Althorp compared to Glacier Bay, although this may simply reflect habitat differences. Sea urchin densities were high in Glacier Bay, while in Port Althorp urchins were virtually absent. Sea otters are now well established in limited areas of the lower portions of Glacier Bay. It is likely that distribution and numbers of sea otters will continue to increase in Glacier Bay in the near future. Glacier Bay supports large and diverse populations of clams that are largely unexploited by sea otters at present. It is predictable that the density and sizes of clam populations will decline in response to otter predation. This will result in fewer opportunities for human harvest, but

  13. The Dead Sea

    NASA Technical Reports Server (NTRS)

    2006-01-01

    The Dead Sea is the lowest point on Earth at 418 meters below sea level, and also one of the saltiest bodies of water on Earth with a salinity of about 300 parts-per-thousand (nine times greater than ocean salinity). It is located on the border between Jordan and Israel, and is fed by the Jordan River. The Dead Sea is located in the Dead Sea Rift, formed as a result of the Arabian tectonic plate moving northward away from the African Plate. The mineral content of the Dead Sea is significantly different from that of ocean water, consisting of approximately 53% magnesium chloride, 37% potassium chloride and 8% sodium chloride. In the early part of the 20th century, the Dead Sea began to attract interest from chemists who deduced that the Sea was a natural deposit of potash and bromine. From the Dead Sea brine, Israel and Jordan produce 3.8 million tons potash, 200,000 tons elemental bromine, 45,000 tons caustic soda, 25, 000 tons magnesium metal, and sodium chloride. Both countries use extensive salt evaporation pans that have essentially diked the entire southern end of the Dead Sea.

    With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop

  14. Panic Disorder among Adults

    MedlinePlus

    ... Hyperactivity Disorder Among Children Autism Spectrum Disorder (ASD) Eating Disorders Among Adults - Anorexia Nervosa Eating Disorders Among Adults - Binge Eating Disorder Eating Disorders Among ...

  15. Bipolar Disorder Among Adults

    MedlinePlus

    ... Hyperactivity Disorder Among Children Autism Spectrum Disorder (ASD) Eating Disorders Among Adults - Anorexia Nervosa Eating Disorders Among Adults - Binge Eating Disorder Eating Disorders Among ...

  16. Major Depression Among Adults

    MedlinePlus

    ... Hyperactivity Disorder Among Children Autism Spectrum Disorder (ASD) Eating Disorders Among Adults - Anorexia Nervosa Eating Disorders Among Adults - Binge Eating Disorder Eating Disorders Among ...

  17. Caribbean Sea Level Network

    NASA Astrophysics Data System (ADS)

    von Hillebrandt-Andrade, C.; Crespo Jones, H.

    2012-12-01

    Over the past 500 years almost 100 tsunamis have been observed in the Caribbean and Western Atlantic, with at least 3510 people having lost their lives to this hazard since 1842. Furthermore, with the dramatic increase in population and infrastructure along the Caribbean coasts, today, millions of coastal residents, workers and visitors are vulnerable to tsunamis. The UNESCO IOC Intergovernmental Coordination Group for Tsunamis and other Coastal Hazards for the Caribbean and Adjacent Regions (CARIBE EWS) was established in 2005 to coordinate and advance the regional tsunami warning system. The CARIBE EWS focuses on four areas/working groups: (1) Monitoring and Warning, (2) Hazard and Risk Assessment, (3) Communication and (4) Education, Preparedness and Readiness. The sea level monitoring component is under Working Group 1. Although in the current system, it's the seismic data and information that generate the initial tsunami bulletins, it is the data from deep ocean buoys (DARTS) and the coastal sea level gauges that are critical for the actual detection and forecasting of tsunamis impact. Despite multiple efforts and investments in the installation of sea level stations in the region, in 2004 there were only a handful of sea level stations operational in the region (Puerto Rico, US Virgin Islands, Bermuda, Bahamas). Over the past 5 years there has been a steady increase in the number of stations operating in the Caribbean region. As of mid 2012 there were 7 DARTS and 37 coastal gauges with additional ones being installed or funded. In order to reach the goal of 100 operational coastal sea level stations in the Caribbean, the CARIBE EWS recognizes also the importance of maintaining the current stations. For this, a trained workforce in the region for the installation, operation and data analysis and quality control is considered to be critical. Since 2008, three training courses have been offered to the sea level station operators and data analysts. Other

  18. Geology of Barents Sea

    SciTech Connect

    Riis, F.; Vollset, J.

    1984-09-01

    The Barents Sea is situated on the continental shelf between Norway, the Spitsbergen Islands, and Novaya Zemlya. The main structural framework of the area was formed during the Caledonian and Hercynian orogenies, whereas the western parts were reactivated by the Kimmerian and Alpine orogenies. Because of the complex opening of the Greenland Norwegian Sea, important tertiary reactivation of Mesozoic normal faults occurred along southwest-northeast-trending systems of wrench faults. Owing to substantial erosion in the late Tertiary, the subsidence history and thermal development are more difficult to unravel in this area than in other places along the Norwegian Shelf. The erosion products were deposited in a huge sedimentary wedge extending onto the oceanic crust. The hydrocarbon discoveries in the Troms area in the southern part of the Barents Sea are encouraging for further exploration. However, the petroleum potential for large areas is not well known at this stage.

  19. Understanding Sea Level Changes

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2004-01-01

    Today more than 100 million people worldwide live on coastlines within one meter of mean sea level; any short-term or long-term sea level change relative to vertical ground motion is of great societal and economic concern. As palm-environment and historical data have clearly indicated the existence and prevalence of such changes in the past, new scientific information regarding to the nature and causes and a prediction capability are of utmost importance for the future. The 10-20 cm global sea-level rise recorded over the last century has been broadly attributed to two effects: (1) the steric effect (thermal expansion and salinity-density compensation of sea water) following global climate; (2) mass-budget changes due to a number of competing geophysical and hydrological processes in the Earth-atmosphere-hydrosphere-cryosphere system, including water exchange from polar ice sheets and mountain glaciers to the ocean, atmospheric water vapor and land hydrological variations, and anthropogenic effects such as water impoundment in artificial reservoirs and extraction of groundwater, all superimposed on the vertical motions of solid Earth due to tectonics, rebound of the mantle from past and present deglaciation, and other local ground motions. As remote-sensing tools, a number of space geodetic measurements of sea surface topography (e.g., TOPEX/Poseidon, Jason), ice mass (e.g., ICESat), time-variable gravity (e.g. GRACE), and ground motions (SLR, VLBI, GPS, InSAR, Laser altimetry, etc.) become directly relevant. Understanding sea level changes "anywhere, anytime" in a well-defined terrestrial reference frame in terms of climate change and interactions among ice masses, oceans, and the solid Earth, and being able to predict them, emerge as one of the scientific challenges in the Solid Earth Science Working Group (SESWG, 2003) conclusions.

  20. Sea-level fluctuations and deep-sea sedimentation rates.

    PubMed

    Worsley, T R; Davies, T A

    1979-02-01

    Sediment accumulation rate curves from 95 drilled cores from the Pacific basin and sea-level curves derived from continental margin seismic stratigraphy show that high biogenous sediment accumulation rates correspond to low eustatic sea levels for at least the last 48 million years. This relationship fits a simple model of high sea levels producing lower land/sea ratios and hence slower chemical erosion of the continents, and vice versa. PMID:17734144

  1. Dynamics of sea level variations in the coastal Red Sea

    NASA Astrophysics Data System (ADS)

    Churchill, James; Abulnaja, Yasser; Nellayaputhenpeedika, Mohammedali; Limeburner, Richard; Lentz, Steven

    2016-04-01

    Sea level variations in the central Red Sea coastal zone span a range of roughly 1.2 m. Though relatively small, these water level changes can significantly impact the environment over the shallow reef tops prevalent in the central Red Sea, altering the water depth by a factor or two or more. While considerable scientific work has been directed at tidal and seasonal variations of Red Sea water level, very little attention has been given to elevation changes in an 'intermediate' frequency band, with periods of 2-30 d, even though motions in this band account for roughly half of the sea level variance in central Red Sea. We examined the sea level signal in this band using AVISO sea level anomaly (SLA) data, COARDAS wind data and measurements from pressure sensors maintained for more than five years at a number of locations in Saudi Arabian coastal waters. Empirical orthogonal function analysis of the SLA data indicates that longer-period (10-30 d) sea level variations in the intermediate band are dominated by coherent motions in a single mode that extends over most of the Red Sea axis. Idealized model results indicate that this large-scale mode of sea level motion is principally due to variations in the large-scale gradient of the along-axis wind. Our analysis indicates that coastal sea level motions at shorter periods (2-10 d) are principally generated by a combination of direct forcing by the local wind stress and forcing associated with large-scale wind stress gradients. However, also contributing to coastal sea level variations in the intermediate frequency band are mesoscale eddies, which are prevalent throughout the Red Sea basin, have a sea level signal of 10's of cm and produce relatively small-scale (order 50 km) changes in coastal sea level.

  2. Mercury and Selenium in Muscle and Target Organs of Scalloped Hammerhead Sharks Sphyrna lewini of the SE Gulf of California: Dietary Intake, Molar Ratios, Loads, and Human Health Risks.

    PubMed

    Bergés-Tiznado, Magdalena E; Márquez-Farías, Fernando; Lara-Mendoza, Raúl E; Torres-Rojas, Yassir E; Galván-Magaña, Felipe; Bojórquez-Leyva, Humberto; Páez-Osuna, Federico

    2015-11-01

    Selenium and mercury were evaluated in muscle, liver, kidney, brain, and the stomach contents of juvenile scalloped hammerhead shark Sphyrna lewini. Se:Hg molar ratios were calculated. The average Hg levels in muscle ranged from 0.12 to 1.17 μg/g (wet weight); Hg was <0.39 μg/g in liver and kidneys and <0.19 μg/g in brain. The lowest value of Se was found in muscle (0.4 μg/g) and the highest in kidney (26.7 μg/g). An excess of Se over Hg was found, with Se:Hg molar ratios >1. Correlations were found for Hg in muscle with size, age, and weight, and also for Hg in liver with size, age, and weight. Hg in muscle was significantly positive correlated to Hg in brain as well as Hg in liver was correlated to Hg in kidney. The highest Hg in preys was for carangid fishes; scombrid and carangid fishes contributed with the highest Se levels. Results suggest that more than 98 % of the total Hg and 62 % of Se end up in muscle and might be affected by factors, such as geographical area, age, size, and feeding habits. The muscle of S. lewini should be consumed by people cautiously so as not to exceed the recommended intake per week. PMID:26369650

  3. Law of the Sea

    SciTech Connect

    Borgese, E.M.

    1983-03-01

    Seabed development will proceed even though the US declined to join 119 nations signing the Law of the Sea Treaty. The new law replaces laissez faire development with management of the seas. The US, Soviet Union, and 15 other countries, while withholding their signatures from the convention, did sign the Final Act of the Conference and can sign as full participants in the future if they choose. The new management approach considers global socio-economic and resource needs. It emphasizes international cooperation in the areas of economic development, disarmament, and in establishing rules and regulations for exploring the seabed. (DCK)

  4. Skin disorders at sea.

    PubMed

    Lucas, Ray; Boniface, Keith; Hite, Michael

    2010-01-01

    The purpose of this study is to characterize the types of skin disorders occurring at sea requiring acute treatment. The case logs of a tele-medicine service for US flagged ships at sea were reviewed from March 1, 2006 until March 1, 2009. Of 1844 total cases, 10% (n = 183) were for skin disorders. Sixty-eight percent (n = 125) were infections, 14% (n = 25) were inflammatory, 7% (n = 13) were environmental, and 11% (n = 20) were non-specific rashes. Cutaneous abscesses and cellulitis (n = 84) were the most common acute skin disorders encountered. In some cases (n = 81), still digital photographs aided in the diagnosis. PMID:20496321

  5. Arctic Sea Ice Maximum 2011

    NASA Video Gallery

    AMSR-E Arctic Sea Ice: September 2010 to March 2011: Scientists tracking the annual maximum extent of Arctic sea ice said that 2011 was among the lowest ice extents measured since satellites began ...

  6. Arizona Adult Education Standards

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2006

    2006-01-01

    Adult education standards are the cornerstone for quality teaching, quality learning, and quality lives. The Arizona Adult Education Standards Initiative (Standards Initiative) represents a proactive effort by Arizona's adult education community to ensure rigor and consistency in program content and student outcomes for adult learners throughout…

  7. Seafloor Control on Sea Ice

    NASA Technical Reports Server (NTRS)

    Nghiem, S. V.; Clemente-Colon, P.; Rigor, I. G.; Hall, D. K.; Neumann, G.

    2011-01-01

    The seafloor has a profound role in Arctic sea ice formation and seasonal evolution. Ocean bathymetry controls the distribution and mixing of warm and cold waters, which may originate from different sources, thereby dictating the pattern of sea ice on the ocean surface. Sea ice dynamics, forced by surface winds, are also guided by seafloor features in preferential directions. Here, satellite mapping of sea ice together with buoy measurements are used to reveal the bathymetric control on sea ice growth and dynamics. Bathymetric effects on sea ice formation are clearly observed in the conformation between sea ice patterns and bathymetric characteristics in the peripheral seas. Beyond local features, bathymetric control appears over extensive ice-prone regions across the Arctic Ocean. The large-scale conformation between bathymetry and patterns of different synoptic sea ice classes, including seasonal and perennial sea ice, is identified. An implication of the bathymetric influence is that the maximum extent of the total sea ice cover is relatively stable, as observed by scatterometer data in the decade of the 2000s, while the minimum ice extent has decreased drastically. Because of the geologic control, the sea ice cover can expand only as far as it reaches the seashore, the continental shelf break, or other pronounced bathymetric features in the peripheral seas. Since the seafloor does not change significantly for decades or centuries, sea ice patterns can be recurrent around certain bathymetric features, which, once identified, may help improve short-term forecast and seasonal outlook of the sea ice cover. Moreover, the seafloor can indirectly influence cloud cover by its control on sea ice distribution, which differentially modulates the latent heat flux through ice covered and open water areas.

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

    NASA Astrophysics Data System (ADS)

    Williams, G. C.

    2015-12-01

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

  9. Alaska and Bering Sea Bloom

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Alaska was relatively clear as was part of the Bering Sea where the aquamarine bloom is still visible in this SeaWiFS image. Credit: Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  10. Egyptian Sea Cave

    ERIC Educational Resources Information Center

    Journal of College Science Teaching, 2005

    2005-01-01

    This brief article describes an archaeological expedition to the Red Sea coast area of Egypt in 2004. Kathryn Bard, an associate professor of archaeology at Boston University, along with her team, discovered the well-preserved cedar timbers of an ancient Egyptian seafaring vessel near the entrance to a large man-made cave. Limestone tablets with…

  11. Solomon's Sea and [Pi

    ERIC Educational Resources Information Center

    Simoson, Andrew J.

    2009-01-01

    This paper is a whimsical survey of the various explanations which might account for the biblical passage in I Kings 7:23 that describes a round object--a bronze basin called Solomon's Sea--as having diameter ten cubits and circumference thirty cubits. Can the biblical pi be any number other than 3? We offer seven different perspectives on this…

  12. Ships to the Sea.

    ERIC Educational Resources Information Center

    Department of the Navy, Washington, DC.

    This lesson contains materials for the U.S. Navy Museum's "Ships to the Sea" program. The program is appropriate for students in grades 2-4 and was designed in accordance with local and national social studies standards. The materials introduce students to the world of ship technology and naval terminology. The lesson is presented in five…

  13. Classroom of the Sea.

    ERIC Educational Resources Information Center

    Hupper, Mary Laporta; Monte, Denise; Scheifele, Peter

    2000-01-01

    Introduces the Sea Program in which participant students were deaf and collaborated with a bioacoustician. Studies the underwater noise levels of the Gulf of Maine and the possible impacts on marine life. Explains implementing this project in the science curriculum. (YDS)

  14. Solar Sea Power

    ERIC Educational Resources Information Center

    Zener, Clarence

    1976-01-01

    In their preoccupation with highly complex new energy systems, scientists and statesmen may be overlooking the possibilities of Ocean Thermal Energy Conversion (OTEC). That is the view of a Carnegie-Mellon University physicist who is in the forefront of solar sea power investigation. (Author/BT)

  15. Modern sea power

    SciTech Connect

    Till, G.

    1987-01-01

    This book provides discussions of political, technical and military aspects of nuclear power. The contents include naval warfare in the nuclear age; politics, money, law and technology; a technological change; implications of technology; sea control; strategic deterrents; amphibious operations, maritime interdiction; inshore operations, naval diplomacy and conclusion.

  16. S.E.A.

    ERIC Educational Resources Information Center

    Hawkins, Richard H.

    1976-01-01

    Sea Semester combines a six-week apprenticeship on a sailing ship with an intensive shore preparation component. Through Boston University, students learn marine and nautical sciences before putting some of this information to practice. Students, having completed the shore and sailing components, can enroll in more advanced shore component…

  17. Virtual sea border

    NASA Astrophysics Data System (ADS)

    Ferriere, D.; Rucinski, A.; Jankowski, T.

    2007-04-01

    Establishing a Virtual Sea Border by performing a real-time, satellite-accessible Internet-based bio-metric supported threat assessment of arriving foreign-flagged cargo ships, their management and ownership, their arrival terminal operator and owner, and rewarding proven legitimate operators with an economic incentive for their transparency will simultaneously improve port security and maritime transportation efficiencies.

  18. The Provident Sea

    NASA Astrophysics Data System (ADS)

    Cushing, David H.

    1988-09-01

    The Provident Sea describes the history of fish stock management (including whales and seals). The book traces, on the basis of the original scientific material, the history of the management of "the provident sea" up to recent times when problems of over-exploitation have had dramatic effects upon stocks. The need for management arose mainly from the increasing industrialization of capture. Hence the preindustrial fisheries are covered, in particular the old cod fishery on the Grand Bank and the herring fishery in the North Sea, as an essential background to current problems. The origins of fisheries and whaling science are described, as is the development up to 1965 of the science and institution in fisheries, whaling, and sealing. In the sixties and seventies, certain major fishing nations took a heavy harvest of fish stocks using sophisticated and efficient gathering methods. This in turn led to conflict and one consequence was the "Law of the Sea" conference set up to try and resolve these issues.

  19. Direct observations of American eels migrating across the continental shelf to the Sargasso Sea.

    PubMed

    Béguer-Pon, Mélanie; Castonguay, Martin; Shan, Shiliang; Benchetrit, José; Dodson, Julian J

    2015-01-01

    Since inferring spawning areas from larval distributions in the Sargasso Sea a century ago, the oceanic migration of adult American eels has remained a mystery. No adult eel has ever been observed migrating in the open ocean or in the spawning area. Here, we track movements of maturing eels equipped with pop-up satellite archival tags from the Scotian Shelf (Canada) into the open ocean, with one individual migrating 2,400 km to the northern limit of the spawning site in the Sargasso Sea. The reconstructed routes suggest a migration in two phases: one over the continental shelf and along its edge in shallow waters; the second in deeper waters straight south towards the spawning area. This study is the first direct evidence of adult Anguilla migrating to the Sargasso Sea and represents an important step forward in the understanding of routes and migratory cues. PMID:26505325

  20. Direct observations of American eels migrating across the continental shelf to the Sargasso Sea

    PubMed Central

    Béguer-Pon, Mélanie; Castonguay, Martin; Shan, Shiliang; Benchetrit, José; Dodson, Julian J.

    2015-01-01

    Since inferring spawning areas from larval distributions in the Sargasso Sea a century ago, the oceanic migration of adult American eels has remained a mystery. No adult eel has ever been observed migrating in the open ocean or in the spawning area. Here, we track movements of maturing eels equipped with pop-up satellite archival tags from the Scotian Shelf (Canada) into the open ocean, with one individual migrating 2,400 km to the northern limit of the spawning site in the Sargasso Sea. The reconstructed routes suggest a migration in two phases: one over the continental shelf and along its edge in shallow waters; the second in deeper waters straight south towards the spawning area. This study is the first direct evidence of adult Anguilla migrating to the Sargasso Sea and represents an important step forward in the understanding of routes and migratory cues. PMID:26505325

  1. The Weddell Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Several large, irregularly shaped icebergs are floating in the Weddell Sea, east of the Antarctic Peninsula, in this true-color MODIS image from February 17, 2002. The location of several of the bergs has changed little over the last three months. Compared to an image acquired on November 13, 2001, the berg at the upper right of the image has spun around, but is still hanging around in the same general location. Similar slow-movers can be seen just to the east of the Larsen Ice Shelf, which hugs the eastern coast of the Peninsula. The northernmost of those two bergs is designated A38b; the southernmost one is A38a. These bergs were once part of an iceberg greater than 2,700 square miles that broke off the Ronne Ice Shelf (to the south) back in 1998. While the waters of the Weddell Sea in the area ought to be deep enough to float those bergs, it is possible that they have run aground on a topographic high, or ridge, in the sea floor. However, little is known about the underwater topography of that region, and it is also possible that the bergs are simply so massive that they resist being moved by surface wind or ocean currents. While four years might seem like a long time for an iceberg to hang around, these are certainly no record holders. A berg that broke off the Ross Ice Shelf (on the other side of Antarctica) drifted north and went aground south of Australia. That berg calved in 1987, and hasn't really moved in ten years. While the big bergs have not moved much in the span of time between these images, there is a big difference in the amount of sea ice present in the two images. In general, the rounder chunks of ice are more likely to be seasonal sea ice that forms from the freezing of sea water, while the larger, jagged-edged pieces of ice are more likely to be bergs that broke off an ice shelf at the margin of the continent. It's the height of summer in Antarctica in the February image, and much of the sea ice has melted or drifted away, leaving a relatively

  2. Stormy oceans are associated with declines in sea turtle hatching.

    PubMed

    Van Houtan, Kyle S; Bass, Oron L

    2007-08-01

    Many sea turtle populations are below 10% of their pre-Columbian numbers [1-4]. Though historic and systematic over-exploitation is the principal cause of these declines, sea turtles face similar threats today. Adults and juveniles are actively hunted and commercial fisheries catch them incidentally. Nesting suffers from beach development, egg poaching and the poaching of nesting females. Accompanying these familiar hazards is the largely unknown consequences of recent climate change. Here we report monitoring surveys from the Dry Tortugas National Park (DTNP, 24.64N 82.86W), Florida, and show that hurricanes and other storm events are an additional and increasing threat to loggerhead turtle (Caretta caretta) and green sea turtle (Chelonia mydas) nesting. Both species are listed by the US Endangered Species Act and the IUCN considers them 'endangered'. PMID:17686427

  3. Northern Sand Sea

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

    This VIS image was taken at 82 degrees North latitude during Northern spring. The image is completely dominated by dunes. In sand seas, it is very common for a single type of dune to occur, and for a single predominate wind to control the alignment of the dunes.

    Image information: VIS instrument. Latitude 82.2, Longitude 152.5 East (207.5 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  4. Adult-Rated Oceanography Part 1: A Project Integrating Ocean Sciences into Adult Basic Education Programs.

    NASA Astrophysics Data System (ADS)

    Cowles, S.; Collier, R.; Torres, M. K.

    2004-12-01

    Busy scientists seek opportunities to implement education and outreach efforts, but often don't know where to start. One easy and tested method is to form collaborations with federally-funded adult education and adult literacy programs. These programs exist in every U.S. state and territory and serve underrepresented populations through such major initiatives as adult basic education, adult secondary education (and GED preparation), and English language acquisition. These students are workers, consumers, voters, parents, grandparents, and members of every community. They have specific needs that are often overlooked in outreach activities. This presentation will describe the steps by which the Oregon Ocean Science and Math Collaborative program was developed. It is based on a partnership between the Oregon Department of Community Colleges and Workforce Development, Oregon State University College of Oceanic and Atmospheric Sciences, Oregon Sea Grant, and the OSU Hatfield Marine Science Center. It includes professional development through instructor institutes; teachers at sea and informal education opportunities; curriculum and web site development. Through the partnership described here, instructors in adult basic education programs participate in a yearlong experience in which they develop, test, and adapt innovative instructional strategies to meet the specific needs of adult learners. This, in turn, leads to new prospects for study in the areas of ocean science and math and introduces non-academic careers in marine science to a new community. Working directly with instructors, we have identified expertise level, instructional environment, instructor background and current teaching strategies used to address science literacy and numeracy goals of the adult learners in the State of Oregon. Preliminary evaluation of our ongoing project in meeting these goals will be discussed. These efforts contribute to national goals of science literacy for all, by providing

  5. Sea-Level Projections from the SeaRISE Initiative

    NASA Technical Reports Server (NTRS)

    Nowicki, Sophie; Bindschadler, Robert

    2011-01-01

    SeaRISE (Sea-level Response to Ice Sheet Evolution) is a community organized modeling effort, whose goal is to inform the fifth IPCC of the potential sea-level contribution from the Greenland and Antarctic ice sheets in the 21st and 22nd century. SeaRISE seeks to determine the most likely ice sheet response to imposed climatic forcing by initializing an ensemble of models with common datasets and applying the same forcing to each model. Sensitivity experiments were designed to quantify the sea-level rise associated with a change in: 1) surface mass balance, 2) basal lubrication, and 3) ocean induced basal melt. The range of responses, resulting from the multi-model approach, is interpreted as a proxy of uncertainty in our sea-level projections. http://websrv.cs .umt.edu/isis/index.php/SeaRISE_Assessment.

  6. 50 CFR 648.58 - Rotational Closed Areas.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Rotational Closed Areas. 648.58 Section... Atlantic Sea Scallop Fishery § 648.58 Rotational Closed Areas. (a)-(b) (c) Transiting. No vessel possessing... species other than scallops. A vessel may fish for species other than scallops within the closed...

  7. 50 CFR 648.58 - Rotational Closed Areas.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Rotational Closed Areas. 648.58 Section... Atlantic Sea Scallop Fishery § 648.58 Rotational Closed Areas. (a) Hudson Canyon Closed Area. No vessel may fish for scallops in, or possess or land scallops from, the area known as the Hudson Canyon Closed...

  8. Adult Cancers in Adolescents and Young Adults.

    PubMed

    Laurence, Valérie; Marples, Maria; Stark, Daniel P

    2016-01-01

    The pattern of cancer seen in young people changes with increasing age, transitioning from childhood- to adult-type cancer in adolescence and the third decade. The risk factors, presentation and biology of cancer in young adults differ from those in the older adult population. Factors of particular significance in adolescents and young adults (AYAs) include genetic predisposition to adult-type cancer, diagnostic uncertainty, long-term morbidity and considerations of fertility. New systemic therapies are being introduced that can prolong life and even increase the chance of cure, but the impact on AYAs is uncertain, as these patients are often under-represented in clinical trials. Here, we discuss the management of AYAs with 3 of the most common cancers affecting adults, when they emerge in the AYA populations, and therefore are currently met by medical oncologists - breast cancer, colorectal cancer and melanoma. PMID:27595357

  9. Sea ice radiative forcing, sea ice area, and climate sensitivity

    NASA Astrophysics Data System (ADS)

    Caldeira, Ken; Cvijanovic, Ivana

    2014-05-01

    Changes in sea ice cover affect climate sensitivity by modifying albedo and surface heat flux exchange, which in turn affect the absorbed solar radiation at the surface as well as cloud cover, atmospheric water content and poleward atmospheric heat transport. Here, we use a configuration of the Community Earth System Model 1.0.4 with a slab ocean model and a thermodynamic-dynamic sea ice model to investigate the overall net effect of feedbacks associated with the sea ice loss. We analyze the strength of the overall sea ice feedback in terms of two factors: the sensitivity of sea ice area to changes in temperature, and the sensitivity of sea ice radiative forcing to changes in sea ice area. In this model configuration, sea ice area decreases by ~3 × 1012 m2 per K of global warming, while the effective global radiative forcing per square meter of sea ice loss is ~0.1 × 10-12 W m-2. The product of these two terms (~0.3 W m-2 K-1) approximately equals the difference in climate feedback parameter found in simulations with sea ice response (1.05 W m-2 K-1) and simulations without sea ice response (1.31 W m-2 K-1 or 1.35 W m-2 K-1, depending on the method used to disable changes in sea ice cover). Thus, we find that in our model simulations, sea ice response accounts for about 20% to 22% of the climate sensitivity to an imposed change in radiative forcing. In our model, the additional radiative forcing resulting from a loss of all sea ice in the 'pre-industrial' state is comparable to but somewhat less than the radiative forcing from a doubling of atmospheric CO2 content.

  10. Sea Ice Radiative Forcing, Sea Ice Area, and Climate Sensitivity

    NASA Astrophysics Data System (ADS)

    Caldeira, K.; Cvijanovic, I.

    2014-12-01

    Changes in sea ice cover affect climate sensitivity by modifying albedo and surface heat flux exchange, which in turn affect the absorbed solar radiation at the surface as well as cloud cover, atmospheric water content and poleward atmospheric heat transport. Here, we use a configuration of the Community Earth System Model 1.0.4 with a slab ocean model and a thermodynamic-dynamic sea ice model to investigate the overall net effect of feedbacks associated with the sea ice loss. We analyze the strength of the overall sea ice feedback in terms of two factors: the sensitivity of sea ice area to changes in temperature, and the sensitivity of sea ice radiative forcing to changes in sea ice area. In this model configuration, sea ice area decreases by ~3 × 1012 m2 per K of global warming, while the effective global radiative forcing per unit area of sea ice loss is ~0.1 × 10-12 W m-2. The product of these two terms (~0.3 W m-2 K-1) approximately equals the difference in climate feedback parameter found in simulations with sea ice response (1.05 W m-2 K-1) and simulations without sea ice response (1.31 W m-2 K-1 or 1.35 W m-2 K-1, depending on the method used to disable the changes in sea ice cover). Thus, we find that in our model simulations, sea ice response accounts for about 20% to 22% of the climate sensitivity to an imposed change in radiative forcing. In our model, the additional radiative forcing resulting from a loss of all sea-ice in the "pre-industrial" state is comparable to but somewhat less than the radiative forcing from a doubling of atmospheric CO2 content.

  11. Sea Turtle Navigation and the Detection of Geomagnetic Field Features

    NASA Astrophysics Data System (ADS)

    Lohmann, Kenneth J.; Lohmann, Catherine M. F.

    The lives of sea turtles consist of a continuous series of migrations. As hatchlings, the turtles swim from their natal beaches into the open sea, often taking refuge in circular current systems (gyres) that serve as moving, open-ocean nursery grounds. The juveniles of many populations subsequently take up residence in coastal feeding areas that are located hundreds or thousands of kilometres from the beaches on which the turtles hatched; some juveniles also migrate between summer and winter habitats. As adults, turtles periodically leave their feeding grounds and migrate to breeding and nesting regions, after which many return to their own specific feeding sites. The itinerant lifestyle characteristic of most sea turtle species is thus inextricably linked to an ability to orient and navigate accurately across large expanses of seemingly featureless ocean.In some sea turtle populations, migratory performance reaches extremes. The total distances certain green turtles (Chelonia mydas) and loggerheads (Caretta caretta) traverse over the span of their lifetimes exceed tens of thousands of kilometres, several times the diameter of the turtle's home ocean basin. Adult migrations between feeding and nesting habitats can require continuous swimming for periods of several weeks. In addition, the paths of migrating turtles often lead almost straight across the open ocean and directly to the destination, leaving little doubt that turtles can navigate to distant target sites with remarkable efficiency.

  12. Fish predation on sea urchins on the Great Barrier Reef

    NASA Astrophysics Data System (ADS)

    Young, M. A. L.; Bellwood, D. R.

    2012-09-01

    Predators are important for regulating adult sea urchin densities. Here, we employ remote underwater video cameras to record diurnal predation on tethered sea urchins at Lizard Island on the Great Barrier Reef (GBR). We identified four fish predators of adult sea urchins ( Balistoides viridescens, Balistapus undulatus, Lethrinus atkinsoni and Choerodon schoenleinii). Predator activity appeared to be site-specific. Balistoides viridescens and B. undulatus (f: Balistidae) were the two most important predators of Echinometra mathaei with the former handling E. mathaei significantly faster (mean 0.7 min) than B. undulatus (5.2 min). Balistoides viridescens also successfully preyed on 70 % of detections, while C. schoenleinii, B. undulatus and L. atkinsoni preyed on just 33, 17 and <1 %, respectively. Additionally, B. viridescens were behaviourally dominant among predator species and were observed as aggressors in 30 encounters with B. undulatus and 8 encounters with L. atkinsoni. In only one encounter was B. viridescens the recipient of any aggression (from B. undulatus). In terms of relative vulnerability, of the three sea urchin species examined, E. mathaei were more vulnerable to predation than Diadema setosum or Echinothrix calamaris, with mean handling times of 1.2, 4.8 and 10.3 min, respectively. Balistoides viridescens and B. undulatus both appear to be able to play an important role as predators of sea urchins on the relatively intact coral reefs of Lizard Island. However, B. viridescens emerge as the most efficient predator in terms of handling speed and the proportion of detections preyed upon. They were also the behaviourally dominant predator. This preliminary study of the predators of sea urchins on the GBR highlights the potential significance of relatively scarce but functionally important species.

  13. Sea ice/climate studies

    NASA Technical Reports Server (NTRS)

    Parkinson, C. L.

    1988-01-01

    The objectives were to determine and analyze the annual cycle of sea ice extents in the Arctic Ocean and peripheral seas and bays over the period 1973 to 1986, looking in particular for any long term trends; to examine the relationship between local sea ice covers and the surrounding atmosphere and ocean; and to examine sea ice as a potential early indicator of climate change. The work involves creating regional and hemispheric time series of sea ice variables from satellite passive microwave data and analyzing these through various intercomparisons amongst themselves and with oceanographic and atmospheric fields.

  14. Polygenetic Karsted Hardground Omission Surfaces in Lower Silurian Neritic Limestones: a Signature of Early Paleozoic Calcite Seas

    NASA Astrophysics Data System (ADS)

    James, Noel P.; Desrochers, André; Kyser, Kurt T.

    2015-04-01

    Exquisitely preserved and well-exposed rocky paleoshoreline omission surfaces in Lower Silurian Chicotte Formation limestones on Anticosti Island, Quebec, are interpreted to be the product of combined marine and meteoric diagenesis. The different omission features include; 1) planar erosional bedding tops, 2) scalloped erosional surfaces, 3) knobs, ridges, and swales at bedding contacts, and 4) paleoscarps. An interpretation is proposed that relates specific omission surface styles to different diagenetic-depositional processes that took place in separate terrestrial-peritidal-shallow neritic zones. Such processes were linked to fluctuations in relative sea level with specific zones of diagenesis such as; 1) karst corrosion, 2) peritidal erosion, 3) subtidal seawater flushing and cementation, and 4) shallow subtidal deposition. Most surfaces are interpreted to have been the result of initial extensive shallow-water synsedimentary lithification that were, as sea level fell, altered by exposure and subaerial corrosion, only to be buried by sediments as sea level rose again. This succession was repeated several times resulting in a suite of recurring polyphase omission surfaces through many meters of stratigraphic section. Synsedimentary cloudy marine cements are well preserved and are thus interpreted to have been calcitic originally. Aragonite components are rare and thought to have to have been dissolved just below the Silurian seafloor. Large molluscs that survived such seafloor removal were nonetheless leached and the resultant megamoulds were filled with synsedimentary calcite cement. These Silurian inner neritic-strandline omission surfaces are temporally unique. They are part of a suite of marine omission surfaces that are mostly found in early Paleozoic neritic carbonate sedimentary rocks. These karsted hardgrounds formed during a calcite-sea time of elevated marine carbonate saturation and extensive marine cement precipitation. The contemporaneous greenhouse

  15. The North Sea - A shelf sea in the Anthropocene

    NASA Astrophysics Data System (ADS)

    Emeis, Kay-Christian; van Beusekom, Justus; Callies, Ulrich; Ebinghaus, Ralf; Kannen, Andreas; Kraus, Gerd; Kröncke, Ingrid; Lenhart, Hermann; Lorkowski, Ina; Matthias, Volker; Möllmann, Christian; Pätsch, Johannes; Scharfe, Mirco; Thomas, Helmuth; Weisse, Ralf; Zorita, Eduardo

    2015-01-01

    Global and regional change clearly affects the structure and functioning of ecosystems in shelf seas. However, complex interactions within the shelf seas hinder the identification and unambiguous attribution of observed changes to drivers. These include variability in the climate system, in ocean dynamics, in biogeochemistry, and in shelf sea resource exploitation in the widest sense by societies. Observational time series are commonly too short, and resolution, integration time, and complexity of models are often insufficient to unravel natural variability from anthropogenic perturbation. The North Sea is a shelf sea of the North Atlantic and is impacted by virtually all global and regional developments. Natural variability (from interannual to multidecadal time scales) as response to forcing in the North Atlantic is overlain by global trends (sea level, temperature, acidification) and alternating phases of direct human impacts and attempts to remedy those. Human intervention started some 1000 years ago (diking and associated loss of wetlands), expanded to near-coastal parts in the industrial revolution of the mid-19th century (river management, waste disposal in rivers), and greatly accelerated in the mid-1950s (eutrophication, pollution, fisheries). The North Sea is now a heavily regulated shelf sea, yet societal goals (good environmental status versus increased uses), demands for benefits and policies diverge increasingly. Likely, the southern North Sea will be re-zoned as riparian countries dedicate increasing sea space for offshore wind energy generation - with uncertain consequences for the system's environmental status. We review available observational and model data (predominantly from the southeastern North Sea region) to identify and describe effects of natural variability, of secular changes, and of human impacts on the North Sea ecosystem, and outline developments in the next decades in response to environmental legislation, and in response to

  16. Poster: the sea urchin.

    PubMed

    2006-11-10

    The announcement of the sequencing of the genome of the sea urchin Strongylocentrotus purpuratus is the latest glowing chapter in the long history of contributions from sea urchin researchers to fundamental principles of cell biology, developmental biology, and gene regulation. A poster created for the print Science presents a timeline of the past and a glimpse into the next stage of research that is being opened up through genomic insights; a PDF of that poster is available for our subscribers. We have also created, for all site visitors, an interactive version of the poster, including additional images, video, and Web resources. Interactive poster (free; requires Flash 8 or higher). PDF of print poster (subscription required). PMID:17095688

  17. Changing Sea Levels

    NASA Astrophysics Data System (ADS)

    Pugh, David

    2004-04-01

    Flooding of coastal communities is one of the major causes of environmental disasters world-wide. This textbook explains how sea levels are affected by astronomical tides, weather effects, ocean circulation and climate trends. Based on courses taught by the author in the U.K. and the U.S., it is aimed at undergraduate students at all levels, with non-basic mathematics being confined to Appendices and a website http://publishing.cambridge.org/resources/0521532183/.

  18. Bering Sea in Bloom

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The surface waters of the Bering Sea around the Pribilof Islands, off Alaska's west coast, exhibited a dark green color on May 15, 2002, in this SeaWiFS true-color image. The green color of the currents there suggests the presence of a large phytoplankton bloom. Careful inspection reveals some a reddish tinges of light reflected by this bloom, particularly in a long east to west band just south of the Pribilof Islands, and just north of the Aleutian Island chain (disappearing toward the lower righthand corner of this scene beneath the cloud bank). Some scientists speculate this could be another Phaeocystis bloom, similar to the bloom of this species that was observed in these waters roughly this time last year. Such blooms are typically accompanied by a strong, unpleasant odor in the immediate vicinity. The light brown color of the surface waters along the Alaskan shoreline are probably due to suspended sediments washed off from the land. Image courtesy the SeaWiFS Project, NASA GSFC, and ORBIMAGE

  19. Curonian Spit, Baltic Sea

    NASA Technical Reports Server (NTRS)

    2006-01-01

    On July 25, 2006, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), flying on NASA's Terra satellite, captured this image of the Curonian (or Courland)spit, the Curonian Lagoon (also known as the Courland Lagoon) it encloses, and part of the Baltic Sea. Just 3,800 meters (about 12,460 feet) at its widest point, the spit encloses a lagoon of some 1,620 square kilometers (625 square miles). In this image, dark blue indicates deep water, and lighter blue indicates shallow and/or sediment-laden water. Different shades of blue distinguish the deeper Baltic Sea and the shallower Curonian Lagoon. Vegetation appears in varying shades of green, paved surfaces and bare ground appear in shades of beige and gray, and sandy areas appear off-white. Obvious sandy areas appear along the length of the spit. On the Baltic Sea side, a thin off-white band of beach runs the length of the spit; on the Curonian Lagoon side, intermittent beaches carve their way into the narrow strip of land.

  20. Dead Sea rhodopsins revisited.

    PubMed

    Bodaker, Idan; Suzuki, Marcelino T; Oren, Aharon; Béjà, Oded

    2012-12-01

    The Dead Sea is a unique hypersaline ecosystem with near toxic magnesium levels (∼2 M), dominance of divalent cations and a slightly acidic pH. Previously, we reported a haloarchaeon related to Halobacterium salinarum to dominate in a microbial bloom that developed in 1992 in the upper water layers of the lake following massive freshwater runoff. Whether this clade also dominated an earlier bloom in 1980-1982 cannot be ascertained as no samples for cultivation-independent analysis were preserved. The presence of the light-driven proton pump bacteriorhodopsin was reported in the 1980-1982 bloom of prokaryotes that had developed in the Dead Sea. To test the hypothesis that bacteriorhodopsin proton pumping may play a major role in determining what type of haloarchaea may dominate in specific bloom conditions, we compared rhodopsin genes recovered from Dead Sea biomass collected in different periods with genes coding for retinal proteins in isolated haloarchaea. Novel bacteriorhodopsin and sensory rhodopsin genes were found in samples collected in 2007 and 2010. The fact that no rhodopsin genes were recovered from samples collected during the 1992 bloom, which was dominated by a single species, suggests that different clades were present in the 1980-1982 and 1992 blooms, and that bacteriorhodopsin proton pumping did not necessarily play a determinative role in the dominance of specific halophiles in the blooms. PMID:23760932

  1. Wood decay at sea

    NASA Astrophysics Data System (ADS)

    Charles, François; Coston-Guarini, Jennifer; Guarini, Jean-Marc; Fanfard, Sandrine

    2016-08-01

    The oceans and seas receive coarse woody debris since the Devonian, but the kinetics of wood degradation remains one of many unanswered questions about the fate of driftwood in the marine environment. A simple gravimetric experiment was carried out at a monitoring station located at the exit of a steep, forested Mediterranean watershed in the Eastern Pyrenees. The objective was to describe and quantify, with standardized logs (in shape, structure and constitution), natural degradation of wood in the sea. Results show that the mass decrease of wood logs over time can be described by a sigmoidal curve. The primary process of wood decay observed at the monitoring station was due to the arrival and installation of wood-boring species that consumed more than half of the total wood mass in six months. Surprisingly, in a region where there is little remaining wood marine infrastructure, "shipworms", i.e. xylophagous bivalves, are responsible for an important part of this wood decay. This suggests that these communities are maintained probably by a frequent supply of a large quantity of riparian wood entering the marine environment adjacent to the watershed. By exploring this direct link between terrestrial and marine ecosystems, our long term objective is to determine how these supplies of terrestrial organic carbon can sustain wood-based marine communities as it is observed in the Mediterranean Sea.

  2. Sea lamprey mark type, marking rate, and parasite-host relationships for lake trout and other species in Lake Ontario

    USGS Publications Warehouse

    Lantry, Brian F.; Adams, Jean V.; Christie, Gavin; Schaner, Teodore; Bowlby, James; Keir, Michael; Lantry, Jana; Sullivan, Paul; Bishop, Daniel; Treska, Ted; Morrison, Bruce

    2015-01-01

    We examined how attack frequency by sea lampreys on fishes in Lake Ontario varied in response to sea lamprey abundance and preferred host abundance (lake trout > 433 mm). For this analysis we used two gill net assessment surveys, one angler creel survey, three salmonid spawning run datasets, one adult sea lamprey assessment, and a bottom trawl assessment of dead lake trout. The frequency of fresh sea lamprey marks observed on lake trout from assessment surveys was strongly related to the frequency of sea lamprey attacks observed on salmon and trout from the creel survey and spawning migrations. Attack frequencies on all salmonids examined were related to the ratio between the abundances of adult sea lampreys and lake trout. Reanalysis of the susceptibility to sea lamprey attack for lake trout strains stocked into Lake Ontario reaffirmed that Lake Superior strain lake trout were among the most and Seneca Lake strain among the least susceptible and that Lewis Lake strain lake trout were even more susceptible than the Superior strain. Seasonal attack frequencies indicated that as the number of observed sea lamprey attacks decreased during June–September, the ratio of healing to fresh marks also decreased. Simulation of the ratios of healing to fresh marks indicated that increased lethality of attacks by growing sea lampreys contributed to the decline in the ratios and supported laboratory studies about wound healing duration.

  3. First in situ observations of the deep-sea carnivorous ascidian Dicopia antirrhinum Monniot C., 1972 in the Western Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Mecho, A.; Aguzzi, J.; Company, J. B.; Canals, M.; Lastras, G.; Turon, X.

    2014-01-01

    Dicopia antirrhinum C. Monniot, 1972 is a rare species of deep-sea ascidian belonging to the Family Octacnemidae, reported at depths of 1000-2500 m in European Atlantic waters. Adult individuals have never been reported before in the Mediterranean Sea, where only seven juvenile specimens were found in 1975 at 500 m water depth in the Central basin (Malta). The affinities of these specimens with D. antirrhinum were noted, but lack of some typical characters of the species in juveniles prevented a definite taxonomical identification. No other member of the Octacnemidae has ever been found in the Mediterranean. In this study we describe the sampling of an adult specimen of D. antirrhinum at around 1100 m water depth on the flank of the La Fonera (Palamós) canyon, Northwestern Mediterranean, confirming their presence in the Mediterranean Sea. We also observed 5 individuals of this species on their natural habitat with a Remotely Operated Vehicle (ROV). Our results highlight the potential occurrence of Octacnemidae, the presence of which has been largely overlooked, in several deep-sea canyon areas within the Western Mediterranean basin. These observations are important because they indicate the need for increased sampling effort with new technologies, such as ROVs, in ecologically relevant habitats such as canyons, in order to obtain a more accurate picture of deep-sea biodiversity in the Mediterranean Sea.

  4. Albatross Long-Distance Navigation: Comparing Adults And Juveniles

    NASA Astrophysics Data System (ADS)

    Åkesson, Susanne; Weimerskirch, Henri

    2005-09-01

    Albatrosses are known for their extreme navigation performance enabling them to locate isolated breeding islands after long-distance migrations across open seas. Little is known about the migration of young albatrosses and how they reach the adults' navigation and foraging skills during the period of immaturity lasting several years and spent permanently flying across the open ocean. We tracked by satellite telemetry the dispersal and migration of 13 juvenile wandering albatrosses from the Crozet Islands during their first year at sea. The young albatrosses covered an average distance of 184,000 km during the first year, restricting their dispersal movement to the unproductive and low wind subtropical Indian Ocean and Tasman Sea. The juveniles initiated the migration by an innate phase of rapid dispersal encoded as a fixed flight direction assisted by southerly winds towards north and northeast. Thereafter each individual restricted its movement to a particular zone of the ocean that will possibly be used until they start breeding 7 10 years later and return in contact with breeding adults. This dispersal in young birds corresponds well with movements observed for adult non-breeding wandering albatrosses. The results show clearly an inherited ability to navigate back to already visited areas in young wandering albatrosses. The juvenile dispersal behaviour and migration at sea suggest a genetically based migration program, encoding navigation to a destination area used throughout the life.

  5. Patient Eye Examinations - Adults

    MedlinePlus

    ... Examinations, Adults Patient Eye Examinations, Children Refractive Errors Scientists in the Laboratory Visual Acuity Testing Patient Eye Examinations, Adults × Warning message Automatic fallback to the cURL connection method kicked in to handle the request. Result code ...

  6. Immunization Schedules for Adults

    MedlinePlus

    ... ACIP Vaccination Recommendations Why Immunize? Vaccines: The Basics Immunization Schedules for Adults in Easy-to-read Formats ... previous immunizations. View or Print a Schedule Recommended Immunizations for Adults (19 Years and Older) by Age ...

  7. Adult Congenital Heart Association

    MedlinePlus

    ... survivable, manageable, yet in the routine years between infancy and adulthood, sometimes forgettable. The Adult Congenital Heart ... understand the continuum of the disease from its infancy. The Adult Congential Heart Association brings together valuable ...

  8. Adult Congenital Heart Association

    MedlinePlus

    ... to ACHA Search The futures of adults with congenital heart disease made brighter by their pasts Get Involved 2016 ... conference theme is "The Changing Landscape of Adult Congenital Heart Disease." Join Us Help us improve the quality of ...

  9. Depression in Older Adults

    ERIC Educational Resources Information Center

    Stickle, Fred; Onedera, Jill D.

    2006-01-01

    The purpose of this article is to address selected aspects of depression in older adults. Specifically, symptoms, risk factors, diagnosis, and interventions for depression in older adults are reviewed.

  10. Adult Learning: A Reader.

    ERIC Educational Resources Information Center

    Sutherland, Peter, Ed.

    This book on adult learning is divided into six sections. Section 1, Cognitive Processes, includes the following chapters: "Cognitive Processes: Contemporary Paradigms of Learning" (Jack Mezirow); "Information Processing, Memory, Age and Adult Learning" (Gillian Boulton-Lewis); "Adult Learners' Metacognitive Behaviour in Higher Education" (Barry…

  11. Aspects of Adult Education.

    ERIC Educational Resources Information Center

    Chandrasekhar, Rajkumari

    This book presents an overview of and prescription for adult education in India. Following an introduction to the problem of illiteracy in India, the book's 14 chapters cover a broad spectrum of adult education issues. Topics discussed include adult education and national development; roles of voluntary organizations, universities, colleges, and…

  12. Dimensions of Adult Learning

    ERIC Educational Resources Information Center

    Foley, Griff, Ed.

    2004-01-01

    This broad introduction to adult and postcompulsory education offers an overview of the field for students, adult educators and workplace trainers. The book establishes an analytical framework to emphasize the nature of learning and agency of learners; examines the core knowledge and skills that adult educators need; discusses policy, research and…

  13. Kids Who Outwit Adults.

    ERIC Educational Resources Information Center

    Seita, John R.; Brendtro, Larry K.

    Kids who distrust adults are highly skilled at hiding their real nature and resisting change. Most adults shun such youths or get mired in conflict with them. Punitive get tough practices as well as traditional flaw-fixing treatment are reactive strategies that often drive these youths further from adult bonds and reinforce oppositional and…

  14. Adult Learners in Universities.

    ERIC Educational Resources Information Center

    Baker, Janette, Ed.

    1981-01-01

    Theories on adult development and learning and some of the Ontario universities' programs and services for the adult learner are examined, and Athabasca University, Alberta's answer to the British Open University, is described. Peter O'Donnell discusses adult learners' needs and explains how Athabasca University serves this specific type of…

  15. Adult Competency Education Resources.

    ERIC Educational Resources Information Center

    Bureau of Occupational and Adult Education (DHEW/OE), Washington, DC. Div. of Adult Education.

    A compilation of brief descriptions of 20 current resources for Adult Performance Level (APL) and Adult Competency Education (ACE) programs, this guide was developed for adult and secondary education administrators, teachers, and program developers who are beginning or are already involved with APL/ACE programs. Each citation contains information…

  16. Adult Competency Education Profile.

    ERIC Educational Resources Information Center

    Bureau of Occupational and Adult Education (DHEW/OE), Washington, DC. Div. of Adult Education.

    A compilation of abstracts of 120 current Adult Performance Level (APL) and Adult Competency Education (ACE) federally supported projects being conducted in 34 States and the District of Columbia, this project profile was developed for adult and secondary education administrators, teachers, and program developers who are beginning or are currently…

  17. Adult Education in Turkey

    ERIC Educational Resources Information Center

    Miser, Rifat; Ural, Ozana; Ünlühisarýklý, Özlem

    2013-01-01

    This study investigates the situation and practices of adult education in Turkey in terms of (a) participants, (b) providers, and (c) program areas. The data were derived from published statistical data and one-to-one interaction with adult education providers when such data are unavailable. Turkey has a long tradition of adult education with…

  18. Navajo Adult Basic Education.

    ERIC Educational Resources Information Center

    Navajo Community Coll., Tsaile, AZ.

    The objectives of this Special Experimental Demonstration Project in Adult Basic Education for the Navajo were: (1) to raise the educational and social level of Navajo adult students who are unable to read, write, and speak English; (2) to assist the Navajo adult students to take advantage of occupational and vocational training programs; (3) to…

  19. The Adult Experience.

    ERIC Educational Resources Information Center

    Belsky, Janet

    The 14 chapters of this textbook chronicle adult development from youth through old age, emphasizing both research and interviews with adults at various stages in their lives. Topics covered include the following: (1) the academic field of adult development; (2) theories and research methods; (3) aging and disease prevention; (4) sexuality and…

  20. Adult Numeracy Core Curriculum.

    ERIC Educational Resources Information Center

    Steeds, Andrew, Ed.

    Designed primarily for adult literacy teachers and tutors, this curriculum describes the content of what should be taught in numeracy programs in order to meet the individual needs of adults through the selection and teaching of skills appropriate to those adults' needs. An introduction describes national standards and qualifications, learners,…

  1. Adults and GNVQs.

    ERIC Educational Resources Information Center

    Pettitt, Aidan

    1996-01-01

    This document is intended for further education colleges in the United Kingdom wishing to extend their General National Vocational Qualification (GNVQ) provision to adults, extend their adult students' options for accreditation, or review the suitability of different qualification routes for adults. It presents information about the development of…

  2. Canadian Adult Basic Education.

    ERIC Educational Resources Information Center

    Brooke, W. Michael, Comp.

    "Trends," a publication of the Canadian Association for Adult Education, is a collection of abstracts on selected subjects affecting adult education; this issue is on adult basic education (ABE). It covers teachers and teacher training, psychological factors relating to the ABE teacher and students, manuals for teachers, instructional materials,…

  3. Adult Survival Skills Assessment.

    ERIC Educational Resources Information Center

    Walsko, Gregory M.

    The purpose of this instrument is to supplement data from the Adult Basic Learning Examination in assessing the functional level of adults in daily situations. It may also be used as a teaching tool for adults requesting tutoring in specific concepts and skills presented in the instrument. This instrument is an informal assessment instrument and…

  4. Adults Role in Bullying

    ERIC Educational Resources Information Center

    Notar, Charles E.; Padgett, Sharon

    2013-01-01

    Do adults play a role in bullying? Do parents, teachers, school staff, and community adult leaders influence bullying behavior in children and teenagers? This article will focus on research regarding all adults who have almost daily contact with children and teens and their part in how bullying is identified, addressed, and prevented. This article…

  5. Adult Learning Assumptions

    ERIC Educational Resources Information Center

    Baskas, Richard S.

    2011-01-01

    The purpose of this study is to examine Knowles' theory of andragogy and his six assumptions of how adults learn while providing evidence to support two of his assumptions based on the theory of andragogy. As no single theory explains how adults learn, it can best be assumed that adults learn through the accumulation of formal and informal…

  6. Adult Education in Greece

    ERIC Educational Resources Information Center

    Kokkos, Alexios

    2008-01-01

    The central aim of this article is to analyse the current situation of adult education in Greece. The article focuses on the following points: (a) the degree of participation in programmes of continuing professional training and general adult education courses, (b) the quality and the outcomes of the adult education provision in Greece, and (c)…

  7. An Adult ESL Curriculum.

    ERIC Educational Resources Information Center

    South Carolina Literacy Resource Center, Columbia.

    This curriculum framework for adult literacy was written by 21 South Carolina adult English-as-a-Second-Language (ESL) instructors, as submitted to the South Carolina Literacy Resource Center. It is based on current theories in the fields of adult education and second language acquisition and is designed to be flexible so that it may be adapted to…

  8. Study of the possible role of pollution in the prevalence of sea nettles in the Chesapeake Bay and the development of a census taking method

    NASA Technical Reports Server (NTRS)

    1971-01-01

    A study of the effect of pollutants on the sea nettle population of Chesapeake Bay was conducted. The effects of pollutants on the polyp stage of the nettle were stressed. Methods of detecting adult sea nettles by remote sensing are discussed. The effects of phosphate, nitrate, ammonium, and combinations of these pollutants were investigated.

  9. The dental pathology of southern sea otters (Enhydra lutris nereis).

    PubMed

    Winer, J N; Liong, S M; Verstraete, F J M

    2013-01-01

    Skulls (n = 1,205) of southern sea otters were examined macroscopically according to defined criteria. The museum specimens, acquired from strandings, varied in age from juvenile to adult, with an equal sex distribution. The results from all young adult and adult specimens were pooled according to tooth type. Ninety-two percent of teeth were available for examination, with 6.5% artifactually absent, 0.6% deemed absent due to acquired tooth loss and 0.03% deemed congenitally absent. All teeth were normal in morphology, except for three pairs of fused teeth, including two instances of fused maxillary first incisor teeth. Supernumerary teeth were associated with 97 normal teeth (most commonly maxillary canine teeth) in 68 specimens. At least one persistent deciduous tooth was present in six skulls, two of which were from adults. The majority (94.6%) of alveoli, either with or without teeth, were not associated with bony changes consistent with periodontitis; however, the majority (74.4%) of specimens did have at least one tooth associated with mild periodontitis. The mesial root of the mandibular third premolar tooth was the most common location at which periodontal hard tissue lesions were observed (56.6%). Ten sea otters had lesions consistent with focal enamel hypoplasia. Approximately half of the teeth (52.0%) were abraded; almost all adult specimens (98.1%) contained at least one abraded tooth, while fewer young adults were affected (76.4%). Tooth fractures were uncommon, affecting 1,343 teeth (4.5%). Periapical lesions were associated with 409 teeth (1.3%) in a total of 176 specimens, and these would likely have caused considerable morbidity while the animals were alive. PMID:23348015

  10. Life stage dependent responses to the lampricide, 3-trifluoromethyl-4-nitrophenol (TFM), provide insight into glucose homeostasis and metabolism in the sea lamprey (Petromyzon marinus).

    PubMed

    Henry, Matthew; Birceanu, Oana; Clifford, Alexander M; McClelland, Grant B; Wang, Yuxiang S; Wilkie, Michael P

    2015-03-01

    The primary method of sea lamprey (Petromyzon marinus) control in the Great Lakes is the treatment of streams and rivers with the pesticide 3-trifluoromethyl-4-nitrophenol (TFM), which targets larval sea lamprey. However, less is known about the effects of TFM on other stages of the sea lamprey's complex life cycle. The goal of this study was to determine how TFM affected internal energy stores, metabolites, and ion balance in larval, juvenile (parasitic) and adult sea lamprey. The larvae were more tolerant to TFM than the adults, with a 2-fold higher 12h TFM LC50 and a 1.5-fold higher LC99.9. Acute (3h) exposure of the larvae, parasites and adults to their respective 12h TFM LC99.9 led to marked reductions in glycogen and phosphocreatine in the adult brain, with lesser or no effect in the larvae and parasites. Increased lactate in the brain, at less than the expected stoichiometry, suggested that it was exported to the blood. Kidney glycogen declined after TFM exposure, suggesting that this organ plays an important role in glucose homeostasis. TFM-induced disturbances to ion balance were minimal. In conclusion, TFM perturbs energy metabolism in all major stages of the sea lamprey life cycle in a similar fashion, but the adults appear to be the most sensitive. Thus, the adult stage could be a viable and effective target for TFM treatment, particularly when used in combination with other existing and emerging strategies of sea lamprey control. PMID:25576187

  11. Ontogeny of Oxygen Storage Capacity and Diving Ability in the Southern Sea Otter (Enhydra lutris nereis): Costs and Benefits of Large Lungs.

    PubMed

    Thometz, Nicole M; Murray, Michael J; Williams, Terrie M

    2015-01-01

    Small body size, large lungs, and dense pelage contribute to the unique challenges faced by diving sea otters (Enhydra lutris) when compared to other marine mammals. Here we determine the consequences of large lungs on the development of diving ability in southern sea otters (Enhydra lutris nereis) by examining the ontogeny of blood, muscle, and lung oxygen stores and calculating aerobic dive limits (cADL) for immature and mature age classes. Total oxygen storage capacity matures rapidly in sea otters, reaching adult levels by 2 mo postpartum. But this result is driven by exceptional lung capacity at birth, followed by a decrease in mass-specific lung volume with age. Blood and muscle oxygen stores remain well below adult values before weaning, with large pups exhibiting 74% and 54% of adult values, respectively. Slow muscle development limits the capacity of immature sea otters to dive against high positive buoyancy due to comparatively large lungs. Immature sea otters diving with total lung capacity (TLC) experience up to twice the mass-specific positive buoyancy as adults diving with TLC but can reduce these forces to comparable adult levels by using a smaller diving lung volume (DLV). The cADL of a juvenile with DLV is 3.62 min, while the cADL of an adult with TLC is 4.82 min. We find that the magnitude of positive buoyancy experienced by sea otters changes markedly with age and strongly influences the ontogeny of diving ability in this species. PMID:25860829

  12. Factors influencing capture of invasive sea lamprey in traps baited with a synthesized sex pheromone component

    USGS Publications Warehouse

    Johnson, Nicholas; Siefkes, Michael J.; Wagner, C. Michael; Bravener, Gale; Steeves, Todd; Twohey, Michael; Li, Weiming

    2015-01-01

    The sea lamprey, Petromyzon marinus, is emerging as a model organism for understanding how pheromones can be used for manipulating vertebrate behavior in an integrated pest management program. In a previous study, a synthetic sex pheromone component 7α,12α, 24-trihydroxy-5α-cholan-3-one 24-sulfate (3kPZS) was applied to sea lamprey traps in eight streams at a final in-stream concentration of 10−12 M. Application of 3kPZS increased sea lamprey catch, but where and when 3kPZS had the greatest impact was not determined. Here, by applying 3kPZS to additional streams, we determined that overall increases in yearly exploitation rate (proportion of sea lampreys that were marked, released, and subsequently recaptured) were highest (20–40 %) in wide streams (~40 m) with low adult sea lamprey abundance (<1000). Wide streams with low adult abundance may be representative of low-attraction systems for adult sea lamprey and, in the absence of other attractants (larval odor, sex pheromone), sea lamprey may have been more responsive to a partial sex pheromone blend emitted from traps. Furthermore, we found that the largest and most consistent responses to 3kPZS were during nights early in the trapping season, when water temperatures were increasing. This may have occurred because, during periods of increasing water temperatures, sea lamprey become more active and males at large may not have begun to release sex pheromone. In general, our results are consistent with those for pheromones of invertebrates, which are most effective when pest density is low and when pheromone competition is low.

  13. Factors Influencing Capture of Invasive Sea Lamprey in Traps Baited With a Synthesized Sex Pheromone Component.

    PubMed

    Johnson, Nicholas S; Siefkes, Michael J; Wagner, C Michael; Bravener, Gale; Steeves, Todd; Twohey, Michael; Li, Weiming

    2015-10-01

    The sea lamprey, Petromyzon marinus, is emerging as a model organism for understanding how pheromones can be used for manipulating vertebrate behavior in an integrated pest management program. In a previous study, a synthetic sex pheromone component 7α,12α, 24-trihydroxy-5α-cholan-3-one 24-sulfate (3kPZS) was applied to sea lamprey traps in eight streams at a final in-stream concentration of 10(-12) M. Application of 3kPZS increased sea lamprey catch, but where and when 3kPZS had the greatest impact was not determined. Here, by applying 3kPZS to additional streams, we determined that overall increases in yearly exploitation rate (proportion of sea lampreys that were marked, released, and subsequently recaptured) were highest (20-40%) in wide streams (~40 m) with low adult sea lamprey abundance (<1000). Wide streams with low adult abundance may be representative of low-attraction systems for adult sea lamprey and, in the absence of other attractants (larval odor, sex pheromone), sea lamprey may have been more responsive to a partial sex pheromone blend emitted from traps. Furthermore, we found that the largest and most consistent responses to 3kPZS were during nights early in the trapping season, when water temperatures were increasing. This may have occurred because, during periods of increasing water temperatures, sea lamprey become more active and males at large may not have begun to release sex pheromone. In general, our results are consistent with those for pheromones of invertebrates, which are most effective when pest density is low and when pheromone competition is low. PMID:26399432

  14. Sea Otter, River Otter. The Wonder Series.

    ERIC Educational Resources Information Center

    Robinson, Sandra Chisholm

    This curriculum guide is all about otters and provides information on both sea and river otters. Included are activities related to the diet of sea otters, the adaptations sea otters have made to live in the sea, their tool-using abilities, where they live and how to spot them, comparative anatomy of sea and river otters, and otter movement. The…

  15. Experiencing the Full Research Process at Sea Education Association (SEA)

    NASA Astrophysics Data System (ADS)

    Harris, S. E.; Joyce, P.; Jaroslow, G.; Graziano, L.; Lea, C.; Witting, J.; Bower, A.

    2003-12-01

    While some undergraduate research experiences include only a small piece of the research process, students attending Sea Education Association's SEA Semester complete all aspects of oceanographic research in an intensive 12 week program that earns a full semester's credit. In the first half of the program, students read and discuss background literature on a subject, ask questions, pose hypotheses, and develop a written research proposal, which they defend orally. The second half of the course takes place at sea on one of SEA's state-of-the-art oceanographic research vessels where students carry out their sampling plans, analyze samples and data, write a final paper and present their results before the vessel reaches port, completing the course. At sea, students participate in sample collection and analysis for all student projects in addition to learning the general oceanography along their cruise track. This structure exposes students to the realities of research from start to finish and allows them to take full ownership of their projects. In addition to honing writing, public speaking, and problem-solving skills, students learn that research requires dedication, flexibility, and creativity, particularly when their results are unexpected or negate their hypothesis. SEA's undergraduate research program has been developing since 1971. Over that time, SEA has collected an extensive historical oceanographic database in the western Atlantic and Caribbean, plus Pacific data since 2001. This database is available to both students and outside research scientists. Collaborations with scientists outside SEA enhance the student experience and help facilitate oceanographic research by providing "ship-of-opportunity" sampling in remote locations. SEA Semester provides an excellent model for undergraduate research experiences with over 5000 alumni, about 30% of whom enter graduate school. About half the students in SEA's undergraduate programs are non-science majors. Although

  16. Reef-Fidelity and Migration of Tiger Sharks, Galeocerdo cuvier, across the Coral Sea

    PubMed Central

    Werry, Jonathan M.; Planes, Serge; Berumen, Michael L.; Lee, Kate A.; Braun, Camrin D.; Clua, Eric

    2014-01-01

    Knowledge of the habitat use and migration patterns of large sharks is important for assessing the effectiveness of large predator Marine Protected Areas (MPAs), vulnerability to fisheries and environmental influences, and management of shark–human interactions. Here we compare movement, reef-fidelity, and ocean migration for tiger sharks, Galeocerdo cuvier, across the Coral Sea, with an emphasis on New Caledonia. Thirty-three tiger sharks (1.54 to 3.9 m total length) were tagged with passive acoustic transmitters and their localised movements monitored on receiver arrays in New Caledonia, the Chesterfield and Lord Howe Islands in the Coral Sea, and the east coast of Queensland, Australia. Satellite tags were also used to determine habitat use and movements among habitats across the Coral Sea. Sub-adults and one male adult tiger shark displayed year-round residency in the Chesterfields with two females tagged in the Chesterfields and detected on the Great Barrier Reef, Australia, after 591 and 842 days respectively. In coastal barrier reefs, tiger sharks were transient at acoustic arrays and each individual demonstrated a unique pattern of occurrence. From 2009 to 2013, fourteen sharks with satellite and acoustic tags undertook wide-ranging movements up to 1114 km across the Coral Sea with eight detected back on acoustic arrays up to 405 days after being tagged. Tiger sharks dove 1136 m and utilised three-dimensional activity spaces averaged at 2360 km3. The Chesterfield Islands appear to be important habitat for sub-adults and adult male tiger sharks. Management strategies need to consider the wide-ranging movements of large (sub-adult and adult) male and female tiger sharks at the individual level, whereas fidelity to specific coastal reefs may be consistent across groups of individuals. Coastal barrier reef MPAs, however, only afford brief protection for large tiger sharks, therefore determining the importance of other oceanic Coral Sea reefs should be a

  17. Sea Urchin Morphogenesis.

    PubMed

    McClay, David R

    2016-01-01

    In the sea urchin morphogenesis follows extensive molecular specification. The specification controls the many morphogenetic events and these, in turn, precede patterning steps that establish the larval body plan. To understand how the embryo is built it was necessary to understand those series of molecular steps. Here an example of the historical sequence of those discoveries is presented as it unfolded over the last 50 years, the years during which major progress in understanding development of many animals and plants was documented by CTDB. In sea urchin development a rich series of experimental studies first established many of the phenomenological components of skeletal morphogenesis and patterning without knowledge of the molecular components. The many discoveries of transcription factors, signals, and structural proteins that contribute to the shape of the endoskeleton of the sea urchin larva then followed as molecular tools became available. A number of transcription factors and signals were discovered that were necessary for specification, morphogenesis, and patterning. Perturbation of the transcription factors and signals provided the means for assembling models of the gene regulatory networks used for specification and controlled the subsequent morphogenetic events. The earlier experimental information informed perturbation experiments that asked how patterning worked. As a consequence it was learned that ectoderm provides a series of patterning signals to the skeletogenic cells and as a consequence the skeletogenic cells secrete a highly patterned skeleton based on their ability to genotypically decode the localized reception of several signals. We still do not understand the complexity of the signals received by the skeletogenic cells, nor do we understand in detail how the genotypic information shapes the secreted skeletal biomineral, but the current knowledge at least outlines the sequence of events and provides a useful template for future

  18. The Sea Around Us

    NASA Astrophysics Data System (ADS)

    Carson, Rachel L.

    1991-12-01

    Published in 1951, The Sea Around Us is one of the most remarkably successful books ever written about the natural world. Rachel Carson's rare ability to combine scientific insight with moving, poetic prose catapulted her book to first place on The New York Times best-seller list, where it enjoyed wide attention for thirty-one consecutive weeks. It remained on the list for more than a year and a half and ultimately sold well over a million copies, has been translated into 28 languages, inspired an Academy Award-winning documentary, and won both the 1952 National Book Award and the John Burroughs Medal. This classic work remains as fresh today as when it first appeared. Carson's writing teems with stunning, memorable images--the newly formed Earth cooling beneath an endlessly overcast sky; the centuries of nonstop rain that created the oceans; giant squids battling sperm whales hundreds of fathoms below the surface; and incredibly powerful tides moving 100 billion tons of water daily in the Bay of Fundy. Quite simply, she captures the mystery and allure of the ocean with a compelling blend of imagination and expertise. Reintroducing a classic work to a whole new generation of readers, this Special Edition features a new chapter written by Jeffrey Levinton, a leading expert in marine ecology, that brings the scientific side of The Sea Around Us completely up to date. Levinton incorporates the most recent thinking on continental drift, coral reefs, the spread of the ocean floor, the deterioration of the oceans, mass extinction of sea life, and many other topics. In addition, acclaimed nature writer Ann Zwinger has contributed a brief foreword. Today, with the oceans endangered by the dumping of medical waste and ecological disasters such as the Exxon oil spill in Alaska, this illuminating volume provides a timely reminder of both the fragility and the importance of the ocean and the life that abounds within it. Anyone who loves the sea, or who is concerned about our

  19. Sensitivity Studies of Sea Ice Formation In The Kara Sea

    NASA Astrophysics Data System (ADS)

    Hübner, U.; Harms, I.; Backhaus, J. O.

    Sea ice formation is an important process in Arctic shelf seas because it determines environmental conditions in the whole Arctic, in particular at the coasts. Arctic shelf seas receive large amounts of freshwater which has a significant impact on ice forma- tion and which could be affected by climate change. In order to study the direct and indirect influence of river runoff on sea ice formation, a high resolution baroclinic 3-d circulation and sea ice model is applied to the Kara Sea. The model is forced with realistic atmospheric winds, surface heat fluxes, river runoff and tides. A vertical adaptive grid is used which provides high resolution in critical areas such as shallow estuaries, slopes or topographic obstacles. The surface following boundary layer is resolved uniformly in 4 m intervals in order to resolve the strong vertical stratification. The simulated melting rates are sensitive to the penetration depth of shortwave radia- tion into the water column. Peak runoff rates in the Kara Sea in spring might exceed 100.000 m3/s which causes high suspended loads in the water column and reduces the shortwave penetration depth considerably compared to ambient Arctic waters. As a result, coastal sea surface temperatures rise and ice melting is significantly enhanced. Our sensitivity studies show, that the indirect influence of river runoff on ice melting could play an important role in future studies on climate variability in the Arctic.

  20. Two Sea-Level Challenges

    NASA Astrophysics Data System (ADS)

    Galvin, C.

    2008-12-01

    "No place on the sandy ocean shores of the world has been shown to be eroding because of sea level rise." This statement appeared nearly 19 years ago in bold print at the top of the page in a brief article published in Shore and Beach (Galvin,1990). The term "sea level rise" was defined in 1990 as follows: "In this statement, "sea level rise" has the meaning that the average person on the street usually attaches to that term. That is, sea level is rising; not, as in some places like the Mississippi River delta, land level is sinking." While still a subject of controversy, it is now (2008) increasingly plausible (Tornqvist et al,2008) that damage from Hurricane Katrina was significantly worse on the Mississippi River delta because floodwaters exploited wetlands and levees whose elevations had been lowered by decades of compaction in the underlying soil. (1) "Sea level" commonly appears in the literature as "relative sea level rise", occurring that way in 711 publications between 1980 and 2009 (GeoRef database on 8 Sep 08). "Relative sea level rise" does not appear in the 2005 AGI Glossary. The nearest Glossary term is "relative change in sea level", but that term occurs in only 12 publications between 1980 and 2009. The Glossary defines this term in a sequence stratigraphy sense, which infers that "relative sea level rise" is the sum of bottom subsidence and eustatic sea level rise. In plain English, "relative sea level rise" means "water depth increase". For present day coastal environments, "relative sea level rise" is commonly used where eustatic sea level rise is less than subsidence, that is, where the magnitude of actual sea level rise is smaller than the magnitude of subsidence. In that situation, "relative sea level rise" misleads both the average person and the scientist who is not a coastal geologist. Thus, the first challenge is to abandon "relative sea level rise" in favor of "water depth increase", in order that the words accurately descibe what happens

  1. Can sea urchins beat the heat? Sea urchins, thermal tolerance and climate change

    PubMed Central

    2015-01-01

    The massive die-off of the long-spined sea urchin, Diadema antillarum, a significant reef grazer, in the mid 1980s was followed by phase shifts from coral dominated to macroalgae dominated reefs in the Caribbean. While Diadema populations have recovered in some reefs with concomitant increases in coral cover, the additional threat of increasing temperatures due to global climate change has not been investigated in adult sea urchins. In this study, I measured acute thermal tolerance of D. antillarum and that of a sympatric sea urchin not associated with coral cover, Echinometra lucunter, over winter, spring, and summer, thus exposing them to substantial natural thermal variation. Animals were taken from the wild and placed in laboratory tanks in room temperature water (∼22 °C) that was then heated at 0.16–0.3 °C min−1 and the righting behavior of individual sea urchins was recorded. I measured both the temperature at which the animal could no longer right itself (TLoR) and the righting time at temperatures below the TLoR. In all seasons, D. antillarum exhibited a higher mean TLoR than E. lucunter. The mean TLoR of each species increased with increasing environmental temperature revealing that both species acclimatize to seasonal changes in temperatures. The righting times of D. antillarum were much shorter than those of E. lucunter. The longer relative spine length of Diadema compared to that of Echinometra may contribute to their shorter righting times, but does not explain their higher TLoR. The thermal safety margin (the difference between the mean collection temperature and the mean TLoR) was between 3.07–3.66 °C for Echinometra and 3.79–5.67 °C for Diadema. While these thermal safety margins exceed present day temperatures, they are modest compared to those of temperate marine invertebrates. If sea temperatures increase more rapidly than can be accommodated by the sea urchins (either by genetic adaptation, phenotypic plasticity, or both), this

  2. Can sea urchins beat the heat? Sea urchins, thermal tolerance and climate change.

    PubMed

    Sherman, Elizabeth

    2015-01-01

    The massive die-off of the long-spined sea urchin, Diadema antillarum, a significant reef grazer, in the mid 1980s was followed by phase shifts from coral dominated to macroalgae dominated reefs in the Caribbean. While Diadema populations have recovered in some reefs with concomitant increases in coral cover, the additional threat of increasing temperatures due to global climate change has not been investigated in adult sea urchins. In this study, I measured acute thermal tolerance of D. antillarum and that of a sympatric sea urchin not associated with coral cover, Echinometra lucunter, over winter, spring, and summer, thus exposing them to substantial natural thermal variation. Animals were taken from the wild and placed in laboratory tanks in room temperature water (∼22 °C) that was then heated at 0.16-0.3 °C min(-1) and the righting behavior of individual sea urchins was recorded. I measured both the temperature at which the animal could no longer right itself (T LoR) and the righting time at temperatures below the T LoR. In all seasons, D. antillarum exhibited a higher mean T LoR than E. lucunter. The mean T LoR of each species increased with increasing environmental temperature revealing that both species acclimatize to seasonal changes in temperatures. The righting times of D. antillarum were much shorter than those of E. lucunter. The longer relative spine length of Diadema compared to that of Echinometra may contribute to their shorter righting times, but does not explain their higher T LoR. The thermal safety margin (the difference between the mean collection temperature and the mean T LoR) was between 3.07-3.66 °C for Echinometra and 3.79-5.67 °C for Diadema. While these thermal safety margins exceed present day temperatures, they are modest compared to those of temperate marine invertebrates. If sea temperatures increase more rapidly than can be accommodated by the sea urchins (either by genetic adaptation, phenotypic plasticity, or both), this

  3. Balancing regional sea level budgets

    NASA Astrophysics Data System (ADS)

    Leuliette, E. W.; Miller, L.; Tamisiea, M. E.

    2015-12-01

    Balancing the sea-level budget is critical to understanding recent and future climate change as well as balancing Earth's energy budget and water budget. During the last decade, advancements in the ocean observing system — satellite altimeters, hydrographic profiling floats, and space-based gravity missions — have allowed the global mean sea level budget to?be assessed with unprecedented accuracy from direct, rather than inferred, estimates. In particular, several recent studies have used the sea-level budget to bound the rate of deep ocean warming [e.g. Llovel et al. 2014]. On a monthly basis, the sum of the steric component estimated from Argo and the ocean mass (barostatic) component from GRACE agree total sea level from Jason within the estimated uncertainties with the residual difference having an r.m.s. of less than 2 mm [Leuliette 2014]. Direct measurements of ocean warming above 2000 m depth during January 2005 and July 2015 explain about one-third of the observed annual rate of global mean sea-level rise. Extending the understanding of the sea-level budget from global mean sea level to regional patterns of sea level change is crucial for identifying regional differences in recent sea level change. The local sea-level budget can be used to identify any systematic errors in the global ocean observing system. Using the residuals from closing the sea level budget, we demonstrate that systematic regional errors remain, in part due to Argo sampling. We also show the effect of applying revised geocentric pole-tide corrections for GRACE [Wahr et al. 2015] and altimetry [Desai et al., 2015].

  4. Long Term Sea Level Change in the Black Sea

    NASA Astrophysics Data System (ADS)

    Cokacar, Tulay; Emin, Özsoy

    2016-04-01

    Since 1992, altimeter missions have dramatically improved our knowledge and understanding of the oceans.This study investigates the long term sea level change during 1992-2015 in the Black Sea. The satellite altimeter data of the Topex-Poseidon, ERS-1 ands ERS-2 missions and sea level variations of 25 tide gauge stations and temperature/salinity data of 25 Argo float observed in the Black Sea are used for the analysis. The altimeter data are assessed and compared with the data from tide gauges and Argo floats in the Black Sea. First ARGO T/S profiles are used to assess the discrepancies observed between the altimeters. Then in situ measurements are compared with multiple altimeter data to detect in situ measurement anomalies and the corrections applied to improve the consistency of the data sets.

  5. Sounds in the Sea

    NASA Astrophysics Data System (ADS)

    Medwin, Herman

    2005-07-01

    Underwater acousticians and acoustical oceanographers use sound as the premier tool to determine the detailed characteristics of physical and biological bodies and processes at sea. Sounds in the Sea is a comprehensive and accessible textbook on ocean acoustics and acoustical oceanography. Chapters 1 9 provide the basic tools of ocean acoustics. The following fifteen chapters are written by many of the world's most successful ocean researchers. These chapters describe modern developments, and are divided into four sections: Studies of the Near Surface Ocean; Bioacoustical Studies; Studies of Ocean Dynamics; Studies of the Ocean Bottom. This is an invaluable textbook for any course in ocean acoustics for the physical and biological ocean sciences, and engineering. It will also serve as a reference for researchers and professionals in ocean acoustics, and an excellent introduction to the topic for scientists from related fields. Will become THE advanced but accessible textbook on all aspects of ocean acoustics for students in oceanography, engineering, and physics, and will also serve as a reference for researchers and professionals Contains fifteen chapters by many of the world's most successful ocean researchers, describing modern research developments Main author Medwin is world-renowned in ocean acoustics

  6. Sea modeling and rendering

    NASA Astrophysics Data System (ADS)

    Cathala, Thierry; Latger, Jean

    2010-10-01

    More and more defence and civil applications require simulation of marine synthetic environment. Currently, the "Future Anti-Surface-Guided-Weapon" (FASGW) or "anti-navire léger" (ANL) missile needs this kind of modelling. This paper presents a set of technical enhancement of the SE-Workbench that aim at better representing the sea profile and the interaction with targets. The operational scenario variability is a key criterion: the generic geographical area (e.g. Persian Gulf, coast of Somalia,...), the type of situation (e.g. peace keeping, peace enforcement, anti-piracy, drug interdiction,...)., the objectives (political, strategic, or military objectives), the description of the mission(s) (e.g. antipiracy) and operation(s) (e.g. surveillance and reconnaissance, escort, convoying) to achieve the objectives, the type of environment (Weather, Time of day, Geography [coastlines, islands, hills/mountains]). The paper insists on several points such as the dual rendering using either ray tracing [and the GP GPU optimization] or rasterization [and GPU shaders optimization], the modelling of sea-surface based on hypertextures and shaders, the wakes modelling, the buoyancy models for targets, the interaction of coast and littoral, the dielectric infrared modelling of water material.

  7. Greenland Sea observations

    SciTech Connect

    Gudmandsen, P.; Mortensen, H.B.; Pedersen, L.T.; Skriver, H.; Minnett, P.

    1992-12-31

    ERS-1 SAR data have been acquired over the Greenland Sea and Fram Strait during two periods, the Ice Phase of three-day repeat cycle from January to March 1992 and a one-month period in the 35-day repeat cycle from 16 July to 15 August 1992. Most data became available by way of the Broadband Data Dissemination System, i.e. with a spatial resolution of about 100 m. With these data various algorithms have been tested to derive sea ice parameters such as ice extent, ice concentration and ice displacement. In the latter period data were collected to support the activities of a research vessel in the area mainly related to the large polynyas that form east and north of Greenland. The formation of polynyas could clearly be outlined but also other phenomena were observed related to the influence of wind streets and gravity waves associated with the atmospheric boundary layer. The data will have to be studied further including full-resolution data to substantiate the conclusions arrived at.

  8. Sea ice terminology

    SciTech Connect

    Not Available

    1980-09-01

    A group of definitions of terms related to sea ice is presented, as well as a graphic representation of late winter ice zonation of the Beaufort Sea Coast. Terms included in the definition list are belt, bergy bit, bight, brash ice, calving, close pack ice, compacting, compact pack ice, concentration, consolidated pack ice, crack, diffuse ice edge, fast ice, fast-ice boundary, fast-ice edge, first-year ice, flaw, flaw lead, floe, flooded ice, fractured, fractured zone, fracturing, glacier, grey ice, grey-white ice, growler, hummock, iceberg, iceberg tongue, ice blink, ice boundary, ice cake, ice edge, ice foot, ice free, ice island, ice shelf, large fracture, lead, medium fracture, multiyear ice, nilas, old ice, open pack ice, open water, pack ice, polar ice, polynya, puddle, rafted ice, rafting, ram, ridge, rotten ice, second-year ice, shearing, shore lead, shore polynya, small fracture, strip, tabular berg, thaw holes, very close pack ice, very open pack ice, water sky, young coastal ice, and young ice.

  9. Ice in Caspian Sea and Aral Sea, Kazakhstan

    NASA Technical Reports Server (NTRS)

    2002-01-01

    In this MODIS image from December 3, 2001, winter sea ice can be seen forming in the shallow waters of the northern Caspian (left) and Aral (upper right) Seas. Despite the inflow of the Volga River (upper left), the northern portion of the Caspian Sea averages only 17 ft in depth, and responds to the region's continental climate, which is cold in winter and hot and dry in the summer. The southern part of the Sea is deeper and remains ice-free throughout the winter. The dirty appearance of the ice may be due to sediment in the water, but may also be due to wind-driven dust. The wind in the region can blow at hurricane-force strength and can cause the ice to pile up in hummocks that are anchored to the sea bottom. The eastern portion of the Aral Sea is also beginning to freeze. At least two characteristics of the Aral Sea 'compete' in determining whether its waters will freeze. The Sea is shallow, which increases the likelihood of freezing, but it is also very salty, which means that lower temperatures are required to freeze it than would be required for fresh water. With average December temperatures of 18o F, it's clearly cold enough to allow ice to form. As the waters that feed the Aral Sea continue to be diverted for agriculture, the Sea becomes shallower and the regional climate becomes even more continental. This is because large bodies of water absorb and retain heat, moderating seasonal changes in temperature. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  10. Age- and sex-specific mortality and population structure in sea otters

    USGS Publications Warehouse

    Bodkin, J.L.; Burdin, A.M.; Ryazanov, D.A.

    2000-01-01

    We used 742 beach-cast carcasses to characterize age- and sex-specific sea otter mortality during the winter of 1990-1991 at Bering Island, Russia. We also examined 363 carcasses recovered after the 1989 grounding of the T/V Exxon Valdez, to characterize age and sex composition in the living western Prince William Sound (WPWS) sea otter population. At Bering Island, mortality was male-biased (81%), and 75% were adults. The WPWS population was female-biased (59%) and most animals were subadult (79% of the males and 45% of the females). In the decade prior to 1990-1991 we found increasing sea otter densities (particularly among males), declining prey resources, and declining weights in adult male sea otters at Bering Island. Our findings suggest the increased mortality at Bering Island in 1990-1991 was a density-dependent population response. We propose male-maintained breeding territories and exclusion of juvenile females by adult females, providing a mechanism for potentially moderating the effects of prey reductions on the female population. Increased adult male mortality at Bearing Island in 1990-1991 likely modified the sex and age class structure there toward that observed in Prince William Sound.

  11. Sea-ice habitat preference of the Pacific walrus (Odobenus rosmarus divergens) in the Bering Sea: A multiscaled approach

    NASA Astrophysics Data System (ADS)

    Sacco, Alexander Edward

    The goal of this thesis is to define specific parameters of mesoscale sea-ice seascapes for which walruses show preference during important periods of their natural history. This research thesis incorporates sea-ice geophysics, marine-mammal ecology, remote sensing, computer vision techniques, and traditional ecological knowledge of indigenous subsistence hunters in order to quantitatively study walrus preference of sea ice during the spring migration in the Bering Sea. Using an approach that applies seascape ecology, or landscape ecology to the marine environment, our goal is to define specific parameters of ice patch descriptors, or mesoscale seascapes in order to evaluate and describe potential walrus preference for such ice and the ecological services it provides during an important period of their life-cycle. The importance of specific sea-ice properties to walrus occupation motivates an investigation into how walruses use sea ice at multiple spatial scales when previous research suggests that walruses do not show preference for particular floes. Analysis of aerial imagery, using image processing techniques and digital geomorphometric measurements (floe size, shape, and arrangement), demonstrated that while a particular floe may not be preferred, at larger scales a collection of floes, specifically an ice patch (< 4 km2), was preferred. This shows that walruses occupy ice patches with distinct ice features such as floe convexity, spatial density, and young ice and open water concentration. Ice patches that are occupied by adult and juvenile walruses show a small number of characteristics that vary from those ice patches that were visually unoccupied. Using synthetic aperture radar imagery, we analyzed co-located walrus observations and statistical texture analysis of radar imagery to quantify seascape preferences of walruses during the spring migration. At a coarse resolution of 100 -- 9,000 km2, seascape analysis shows that, for the years 2006 -- 2008

  12. The Sea Lamprey as an Etiological Model for Biliary Atresia

    PubMed Central

    Chung-Davidson, Yu-Wen; Yeh, Chu-Yin; Li, Weiming

    2015-01-01

    Biliary atresia (BA) is a progressive, inflammatory, and fibrosclerosing cholangiopathy in infants that results in obstruction of both extrahepatic and intrahepatic bile ducts. It is the most common cause for pediatric liver transplantation. In contrast, the sea lamprey undergoes developmental BA with transient cholestasis and fibrosis during metamorphosis, but emerges as a fecund adult with steatohepatitis and fibrosis in the liver. In this paper, we present new histological evidence and compare the sea lamprey to existing animal models to highlight the advantages and possible limitations of using the sea lamprey to study the etiology and compensatory mechanisms of BA and other liver diseases. Understanding the signaling factors and genetic networks underlying lamprey BA can provide insights into BA etiology and possible targets to prevent biliary degeneration and to clear fibrosis. In addition, information from lamprey BA can be used to develop adjunct treatments for patients awaiting or receiving surgical treatments. Furthermore, the cholestatic adult lamprey has unique adaptive mechanisms that can be used to explore potential treatments for cholestasis and nonalcoholic steatohepatitis (NASH). PMID:26101777

  13. Neutrino sea scope takes shape

    NASA Astrophysics Data System (ADS)

    Cartlidge, Edwin

    2016-03-01

    A consortium of European physicists building a vast neutrino detector on the floor of the Mediterranean Sea has unveiled the science it will carry out. The Cubic Kilometre Neutrino Telescope (KM3NeT) will use strings of radiation detectors arranged in a 3D network to measure the light emitted when neutrinos very occasionally interact with the surrounding sea water.

  14. Arctic Sea ice model sensitivities.

    SciTech Connect

    Peterson, Kara J.; Bochev, Pavel Blagoveston; Paskaleva, Biliana Stefanova

    2010-12-01

    Arctic sea ice is an important component of the global climate system and, due to feedback effects, the Arctic ice cover is changing rapidly. Predictive mathematical models are of paramount importance for accurate estimates of the future ice trajectory. However, the sea ice components of Global Climate Models (GCMs) vary significantly in their prediction of the future state of Arctic sea ice and have generally underestimated the rate of decline in minimum sea ice extent seen over the past thirty years. One of the contributing factors to this variability is the sensitivity of the sea ice state to internal model parameters. A new sea ice model that holds some promise for improving sea ice predictions incorporates an anisotropic elastic-decohesive rheology and dynamics solved using the material-point method (MPM), which combines Lagrangian particles for advection with a background grid for gradient computations. We evaluate the variability of this MPM sea ice code and compare it with the Los Alamos National Laboratory CICE code for a single year simulation of the Arctic basin using consistent ocean and atmospheric forcing. Sensitivities of ice volume, ice area, ice extent, root mean square (RMS) ice speed, central Arctic ice thickness,and central Arctic ice speed with respect to ten different dynamic and thermodynamic parameters are evaluated both individually and in combination using the Design Analysis Kit for Optimization and Terascale Applications (DAKOTA). We find similar responses for the two codes and some interesting seasonal variability in the strength of the parameters on the solution.

  15. Probability of sea level rise

    SciTech Connect

    Titus, J.G.; Narayanan, V.K.

    1995-10-01

    The report develops probability-based projections that can be added to local tide-gage trends to estimate future sea level at particular locations. It uses the same models employed by previous assessments of sea level rise. The key coefficients in those models are based on subjective probability distributions supplied by a cross-section of climatologists, oceanographers, and glaciologists.

  16. Adult-Rated Oceanography Part 2: Examples from the Trenches

    NASA Astrophysics Data System (ADS)

    Torres, M. E.; Collier, R.; Cowles, S.

    2004-12-01

    We will share experiences and specific examples from an ongoing Ocean Science and Math Collaborative Project between OSU faculty and Community College instructors from the Oregon system of adult education and workforce development. The participants represent such diverse instructional programs as workforce training, workplace education (cannery workers), adult basic education, adult secondary education (GED preparation), English to Speakers of Other Languages, Family Literacy, and Tribal Education (Confederated Tribes of the Siletz Indians). This collaborative project is designed to integrate ocean sciences into the science, math, and critical thinking curriculum through the professional development activities of adult educators. Our strategy is to tailor new and existing ocean science resources to the needs of adult education instructors. This project provides a wide range of opportunities in time and effort for scientist involvement. Some scientists have chosen to participate in short interviews or conversations with adult educators, which give added value through real-world connections in the context of the larger project. Other participating scientists have made larger time investments, which include presentations at workshops, hosting teacher-at-sea opportunities and leading project planning and implementation efforts. This project serves as an efficient model for scientists to address the broader impact goals of their research. It takes advantage of a variety of established educational outreach resources funded through NSF (e.g. the national COSEE network and GeoEducation grants), NOAA (e.g. SeaGrant education and Ocean Explorer) as well as State and Federal adult education programs (e.g. The National Institute for Literacy Science and Numeracy Special Collection). We recognize the value and creativity inherent in these resources, and we are developing a model to "tune" their presentation, as well as their connection to new oceanographic research, in a manner

  17. 50 CFR 648.51 - Gear and crew restrictions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Measures for the Atlantic Sea Scallop Fishery § 648.51 Gear and crew restrictions. (a) Trawl vessel gear... diamond mesh. (3) Minimum ring size. (i) Unless otherwise required under the Sea Scallop Area Access... rings, running parallel to the long axis of the twine top. (5) Restrictions applicable to sea...

  18. Safeguarding vulnerable adults.

    PubMed

    Griffith, Richard

    Nurses have a professional duty to safeguard vulnerable adults from abuse under the provisions of the Nursing and Midwifery Council's (NMC) revised Code (2015). With adult abuse continuing to increase, all members of the nursing team are well placed to identify and take action to safeguard the vulnerable. This article sets out how the Care Act 2014 seeks to improve the safeguarding of vulnerable adults and the role of nurses in that process. PMID:26153813

  19. Effects of sex pheromones and sexual maturation on locomotor activity in female sea lamprey (Petromyzon marinus).

    PubMed

    Walaszczyk, Erin J; Johnson, Nicholas S; Steibel, Juan Pedro; Li, Weiming

    2013-06-01

    Synchronization of male and female locomotor rhythmicity can play a vital role in ensuring reproductive success. Several physiological and environmental factors alter these locomotor rhythms. As sea lamprey, Petromyzon marinus, progress through their life cycle, their locomotor activity rhythm changes multiple times. The goal of this study was to elucidate the activity patterns of adult female sea lamprey during the sexual maturation process and discern the interactions of these patterns with exposure to male pheromones. During these stages, preovulated and ovulated adult females are exposed to sex pheromone compounds, which are released by spermiated males and attract ovulated females to the nest for spawning. The locomotor behavior of adult females was monitored in a natural stream with a passive integrated tag responder system as they matured, and they were exposed to a sex pheromone treatment (spermiated male washings) or a control (prespermiated male washings). Results showed that, dependent on the hour of day, male sex pheromone compounds reduce total activity (p < 0.05) and cause increases in activity during several daytime hours in preovulated and ovulated females. These results are one of the first examples of how sex pheromones modulate a locomotor rhythm in a vertebrate, and they suggest that the interaction between maturity stage and sex pheromone exposure contributes to the differential locomotor rhythms found in adult female sea lamprey. This phenomenon may contribute to the reproductive synchrony of mature adults, thus increasing reproductive success in this species. PMID:23735501

  20. Effects of sex pheromones and sexual maturation on locomotor activity in female sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Walaszczyk, Erin J.; Johnson, Nicholas S.; Steibel, Juan Pedro; Li, Weiming

    2013-01-01

    Synchronization of male and female locomotor rhythmicity can play a vital role in ensuring reproductive success. Several physiological and environmental factors alter these locomotor rhythms. As sea lamprey, Petromyzon marinus, progress through their life cycle, their locomotor activity rhythm changes multiple times. The goal of this study was to elucidate the activity patterns of adult female sea lamprey during the sexual maturation process and discern the interactions of these patterns with exposure to male pheromones. During these stages, preovulated and ovulated adult females are exposed to sex pheromone compounds, which are released by spermiated males and attract ovulated females to the nest for spawning. The locomotor behavior of adult females was monitored in a natural stream with a passive integrated tag responder system as they matured, and they were exposed to a sex pheromone treatment (spermiated male washings) or a control (prespermiated male washings). Results showed that, dependent on the hour of day, male sex pheromone compounds reduce total activity (p < 0.05) and cause increases in activity during several daytime hours in preovulated and ovulated females. These results are one of the first examples of how sex pheromones modulate a locomotor rhythm in a vertebrate, and they suggest that the interaction between maturity stage and sex pheromone exposure contributes to the differential locomotor rhythms found in adult female sea lamprey. This phenomenon may contribute to the reproductive synchrony of mature adults, thus increasing reproductive success in this species.

  1. Arctic Sea Ice Predictability and the Sea Ice Prediction Network

    NASA Astrophysics Data System (ADS)

    Wiggins, H. V.; Stroeve, J. C.

    2014-12-01

    Drastic reductions in Arctic sea ice cover have increased the demand for Arctic sea ice predictions by a range of stakeholders, including local communities, resource managers, industry and the public. The science of sea-ice prediction has been challenged to keep up with these developments. Efforts such as the SEARCH Sea Ice Outlook (SIO; http://www.arcus.org/sipn/sea-ice-outlook) and the Sea Ice for Walrus Outlook have provided a forum for the international sea-ice prediction and observing community to explore and compare different approaches. The SIO, originally organized by the Study of Environmental Change (SEARCH), is now managed by the new Sea Ice Prediction Network (SIPN), which is building a collaborative network of scientists and stakeholders to improve arctic sea ice prediction. The SIO synthesizes predictions from a variety of methods, including heuristic and from a statistical and/or dynamical model. In a recent study, SIO data from 2008 to 2013 were analyzed. The analysis revealed that in some years the predictions were very successful, in other years they were not. Years that were anomalous compared to the long-term trend have proven more difficult to predict, regardless of which method was employed. This year, in response to feedback from users and contributors to the SIO, several enhancements have been made to the SIO reports. One is to encourage contributors to provide spatial probability maps of sea ice cover in September and the first day each location becomes ice-free; these are an example of subseasonal to seasonal, local-scale predictions. Another enhancement is a separate analysis of the modeling contributions. In the June 2014 SIO report, 10 of 28 outlooks were produced from models that explicitly simulate sea ice from dynamic-thermodynamic sea ice models. Half of the models included fully-coupled (atmosphere, ice, and ocean) models that additionally employ data assimilation. Both of these subsets (models and coupled models with data

  2. Serum vitamin A concentrations in captive sea otters (Enhydra lutris).

    PubMed

    Righton, Alison L; St Leger, Judy A; Schmitt, Todd; Murray, Michael J; Adams, Lance; Fascetti, Andrea J

    2011-03-01

    Individual dietary preferences and difficulty with animal training create challenges and nutritional concerns when evaluating a captive sea otter (Enhydra lutris) diet. The importance of vitamin A within the body reflects the necessity that it be ingested in adequate amounts to ensure optimal health. To compare levels of serum vitamin A concentrations from captive sea otters on daily oral vitamin A supplementation, serum samples from eight adult sea otters from three institutions were evaluated for serum vitamin A concentrations. The eight animals were fed a total of four different diets and received oral supplementation via three different methods. Multiple diet items were analyzed for vitamin A content and were found to have low to nondetectable levels of vitamin A. Oral vitamin A supplementation, as a slurry with dietary items, was shown to be effective and a mean serum concentration of approximately 170 +/- 51 microg/L was obtained for serum vitamin A concentrations in captive sea otters. Captive diets can be modified to increase vitamin A concentration and supplementation and, if accepted, can be used as a means to ensure adequate vitamin A intake. PMID:22946382

  3. Sea urchin immune cells as sentinels of environmental stress.

    PubMed

    Pinsino, Annalisa; Matranga, Valeria

    2015-03-01

    Echinoderms, an ancient and very successful phylum of marine invertebrates, play a central role in the maintenance of ecosystem integrity and are constantly exposed to environmental pressure, including: predation, changes in temperature and pH, hypoxia, pathogens, UV radiation, metals, toxicants, and emerging pollutants like nanomaterials. The annotation of the sea urchin genome, so closely related to humans and other vertebrate genomes, revealed an unusually complex immune system, which may be the basis for why sea urchins can adapt to different marine environments and survive even in hazardous conditions. In this review, we give a brief overview of the morphological features and recognized functions of echinoderm immune cells with a focus on studies correlating stress and immunity in the sea urchin. Immune cells from adult Paracentrotus lividus, which have been introduced in the last fifteen years as sentinels of environmental stress, are valid tools to uncover basic molecular and regulatory mechanisms of immune responses, supporting their use in immunological research. Here we summarize laboratory and field studies that reveal the amenability of sea urchin immune cells for toxicological testing. PMID:25463510

  4. Contrasts in Arctic shelf sea-ice regimes and some implications: Beaufort Sea versus Laptev Sea

    USGS Publications Warehouse

    Reimnitz, E.; Dethleff, D.; Nurnberg, D.

    1994-01-01

    The winter ice-regime of the 500 km) from the mainland than in the Beaufort Sea. As a result, the annual freeze-up does not incorporate old, deep-draft ice, and with a lack of compression, such deep-draft ice is not generated in situ, as on the Beaufort Sea shelf. The Laptev Sea has as much as 1000 km of fetch at the end of summer, when freezing storms move in and large (6 m) waves can form. Also, for the first three winter months, the polynya lies inshore at a water depth of only 10 m. Turbulence and freezing are excellent conditions for sediment entrainment by frazil and anchor ice, when compared to conditions in the short-fetched Beaufort Sea. We expect entrainment to occur yearly. Different from the intensely ice-gouged Beaufort Sea shelf, hydraulic bedforms probably dominate in the Laptev Sea. Corresponding with the large volume of ice produced, more dense water is generated in the Laptev Sea, possibly accompanied by downslope sediment transport. Thermohaline convection at the midshelf polynya, together with the reduced rate of bottom disruption by ice keels, may enhance benthic productivity and permit establishment of open-shelf benthic communities which in the Beaufort Sea can thrive only in the protection of barrier islands. Indirect evidence for high benthic productivity is found in the presence of walrus, who also require year-round open water. By contrast, lack of a suitable environment restricts walrus from the Beaufort Sea, although over 700 km farther to the south. We could speculate on other consequences of the different ice regimes in the Beaufort and Laptev Seas, but these few examples serve to point out the dangers of exptrapolating from knowledge gained in the North American Arctic to other shallow Arctic shelf settings. ?? 1994.

  5. Rapid sea-level rise

    NASA Astrophysics Data System (ADS)

    Cronin, Thomas M.

    2012-11-01

    Several global and regional factors contribute to observed sea-level change along any particular coast. Global processes include changes in ocean mass (glacio-eustasy from ice melt), ocean volume (steric effects), viscoelastic land movements (glacioisostatic adjustment GIA), and changes in terrestrial water storage. Regional processes, often connected to steric and glacial changes, include changes in ocean circulation (Meridional Overturning Circulation [MOC]), glacial melting, local GIA, regional subsidence and others. Paleoclimate, instrumental and modeling studies show that combinations of these factors can cause relatively rapid rates of sea-level rise exceeding 3 mm yr-1 over various timescales along particular coasts. This paper discusses patterns and causes of sea-level rise with emphasis on paleoclimatological records. It then addresses the hypothesis of late Holocene (pre-20th century) sea-level stability in light of paleoclimatic evidence, notably from reconstructions of sea-surface temperature and glacial activity, for significant climate and sea-level variability during this time. The practical difficulties of assessing regional sea-level (SL) patterns at submillennial timescales will be discussed using an example from the eastern United States.

  6. Expression of Pigment Cell-Specific Genes in the Ontogenesis of the Sea Urchin Strongylocentrotus intermedius.

    PubMed

    Ageenko, Natalya V; Kiselev, Konstantin V; Odintsova, Nelly A

    2011-01-01

    One of the polyketide compounds, the naphthoquinone pigment echinochrome, is synthesized in sea urchin pigment cells. We analyzed polyketide synthase (pks) and sulfotransferase (sult) gene expression in embryos and larvae of the sea urchin Strongylocentrotus intermedius from various stages of development and in specific tissues of the adults. We observed the highest level of expression of the pks and sult genes at the gastrula stage. In unfertilized eggs, only trace amounts of the pks and sult transcripts were detected, whereas no transcripts of these genes were observed in spermatozoids. The addition of shikimic acid, a precursor of naphthoquinone pigments, to zygotes and embryos increased the expression of the pks and sult genes. Our findings, including the development of specific conditions to promote pigment cell differentiation of embryonic sea urchin cells in culture, represent a definitive study on the molecular signaling pathways that are involved in the biosynthesis of pigments during sea urchin development. PMID:21804858

  7. Parasitic copepods from Egyptian Red Sea fishes: Bomolochidae Claus, 1875.

    PubMed

    El-Rashidy, Hoda Hassan; Boxshall, Geoffrey Allan

    2016-02-01

    Two species of parasitic copepods from the genus Bomolochus von Nordmann, 1832 (Cyclopoida: Bomolochidae) are redescribed in detail, based on material collected from the gills of Red Sea fishes. Host material was caught at El-tor, near Sharm El-Sheikh, and in the Gulf of Suez, Egypt. Both sexes of Bomolochus bellones Burmeister, 1835 were collected from the gills of a needlefish Tylosurus choram (Rüppell) caught in the Gulf of Suez. This is a new host record. The female is well characterised so only the male is described. Adult females of Bomolochus minus Lin & Ho, 2005 were obtained from the branchial cavities and gills of mojarra Gerres oyena (Forsskål). This species was known only from its original description in Taiwan, and this report constitutes a new host record and a significant range extension. Both parasite species are new records for Egyptian Red Sea waters. PMID:26790683

  8. Clinical pathology and assessment of pathogen exposure in southern and Alaskan sea otters

    USGS Publications Warehouse

    Hanni, K.D.; Mazet, J.A.K.; Gulland, F.M.D.; Estes, James; Staedler, M.; Murray, M.J.; Miller, M.; Jessup, David A.

    2003-01-01

    The southern sea otter (Enhydra lutris nereis) population in California (USA) and the Alaskan sea otter (E. lutris kenyoni) population in the Aleutian Islands (USA) chain have recently declined. In order to evaluate disease as a contributing factor to the declines, health assessments of these two sea otter populations were conducted by evaluating hematologic and/or serum biochemical values and exposure to six marine and terrestrial pathogens using blood collected during ongoing studies from 1995 through 2000. Samples from 72 free-ranging Alaskan, 78 free-ranging southern, and (for pathogen exposure only) 41 debilitated southern sea otters in rehabilitation facilities were evaluated and compared to investigate regional differences. Serum chemistry and hematology values did not indicate a specific disease process as a cause for the declines. Statistically significant differences were found between free-ranging adult southern and Alaskan population mean serum levels of creatinine kinase, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, calcium, cholesterol, creatinine, glucose, phosphorous, total bilirubin, blood urea nitrogen, and sodium. These were likely due to varying parasite loads, contaminant exposures, and physiologic or nutrition statuses. No free-ranging sea otters had signs of disease at capture, and prevalences of exposure to calicivirus, Brucella spp., and Leptospira spp. were low. The high prevalence (35%) of antibodies to Toxoplasma gondii in free-ranging southern sea otters, lack of antibodies to this parasite in Alaskan sea otters, and the pathogen's propensity to cause mortality in southern sea otters suggests that this parasite may be important to sea otter population dynamics in California but not in Alaska. The evidence for exposure to pathogens of public health importance (e.g., Leptospira spp., T. gondii) in the southern sea otter population, and the nai??vete?? of both populations to other pathogens (e

  9. Influences of sea ice on eastern Bering Sea phytoplankton

    NASA Astrophysics Data System (ADS)

    Zhou, Qianqian; Wang, Peng; Chen, Changping; Liang, Junrong; Li, Bingqian; Gao, Yahui

    2015-03-01

    The influence of sea ice on the species composition and cell density of phytoplankton was investigated in the eastern Bering Sea in spring 2008. Diatoms, particularly pennate diatoms, dominated the phytoplankton community. The dominant species were Grammonema islandica (Grunow in Van Heurck) Hasle, Fragilariopsis cylindrus (Grunow) Krieger, F. oceanica (Cleve) Hasle, Navicula vanhoeffenii Gran, Thalassiosira antarctica Comber, T. gravida Cleve, T. nordenskiöeldii Cleve, and T. rotula Meunier. Phytoplankton cell densities varied from 0.08×104 to 428.8×104 cells/L, with an average of 30.3×104 cells/L. Using cluster analysis, phytoplankton were grouped into three assemblages defined by ice-forming conditions: open water, ice edge, and sea ice assemblages. In spring, when the sea ice melts, the phytoplankton dispersed from the sea ice to the ice edge and even into open waters. Thus, these phytoplankton in the sea ice may serve as a "seed bank" for phytoplankton population succession in the subarctic ecosystem. Moreover, historical studies combined with these results suggest that the sizes of diatom species have become smaller, shifting from microplankton to nannoplankton-dominated communities.

  10. SMOS Sea Surface Salinity Validation in the South China Sea

    NASA Astrophysics Data System (ADS)

    Ren, Yongzheng; Li, Xiaoming; Dong, Qing

    2013-01-01

    In November 2009, the European Space Agency (ESA) launched the first soil moisture and ocean salinity (SMOS) satellite, which represented the first use of spaceborne remote sensing tools to probe global sea surface salinity (SSS). The SMOS satellite carries a microwave imaging radiometer with aperture synthesis (MIRAS) for detection in the microwave L-band as the only payload. The MIRAS instrument is expected to provide a global SSS distribution with a spatial resolution of approximately 100 km and an accuracy of 0.1-0.2 practical salinity units (psu). The South China Sea is semi-enclosed, and the sea conditions are relatively complex. The suitability of ESA SMOS salinity products for the South China Sea has not been validated. Therefore, using SSS data measured during an expedition in the South China Sea, which was sponsored by China Natural Science Foundation and conducted in the fall of 2011, this paper validated the SSS products released by ESA, which were retrieved using three sea surface roughness models. To analyze the effect of the spatial resolution on the weekly average SMOS SSS distribution, the weekly average salinity data were averaged to reduce the spatial resolution to 0.25 ° x 0.25°. These average data were then compared to the measured data, followed by an analysis of the error variation. In addition, the effects of the orbital track (ascending or descending) on the SSS retrieval were analyzed.

  11. Tortuosity of the Antarctic Sea Ice over the Weddell Sea

    NASA Astrophysics Data System (ADS)

    Beard, J.; Heinrichs, J. F.

    2011-12-01

    The objective of the research was to mathematically characterize the edge of the Antarctic sea ice in the Weddell Sea. Because the sea ice may reflect processes involved in the atmosphere and ocean near the ice edge, it may suggest broader changes on the ice. The chosen method was to compare the tortuosity of the edge over time and across seasons. Because the sea ice may reflect processes involved in the atmosphere and ocean near the ice edge, it may suggest broader changes on the ice. Throughout the research, the shapefiles for the Antarctic sea ice were collected from the National Snow and Ice Data Center website and the coordinates were extracted using an add-in for the MapWindow GIS. These points were then put into Excel separated by year and then the distance factor (an approximation to the tortuosity) was calculated and compared by month over time. Preliminary data has shown that the closer to the winter months, the higher the tortuosity. Statistical analysis has shown that there is no clear relationship between tortuosity and the area of the sea ice, and the tortuosity exhibits a weak negative trend over the past 32 years.

  12. Alternative Programming for Adults.

    ERIC Educational Resources Information Center

    Flint, Thomas A.; Frey, Ruth

    2003-01-01

    The Council for Adult and Experiential Learning is currently cataloguing alternative programming features that are most effective with adult students in a best practices inventory organized around a framework of high-level descriptive principles of effectiveness. This chapter identifies a few interesting features from a quick survey of this…

  13. Adult Education in Germany.

    ERIC Educational Resources Information Center

    Huddleston, John

    This study is limited essentially to adult education in West Germany, although the historical sections include references to earlier experiences and experiments in areas now Russian-occupied. The terms "adult edcuation" and "workers' education" are clarified. Both are presented as separate movements. Brief reference is made to political, social,…

  14. Adult Learning Matters

    ERIC Educational Resources Information Center

    Thomson, Rachel

    2009-01-01

    Adult Learners' Week--which is supported by the Department for Innovation, Universities and Skills and the European Social Fund, amongst a raft of other organisations--is all about raising demand for learning. At its core, the campaign is about encouraging under-represented groups--including low-skilled, unemployed and low-paid adults and those…

  15. Teachers of Adults Will...

    ERIC Educational Resources Information Center

    Pankowski, Mary L.

    1975-01-01

    The article lists the 12 competencies of adult education teachers that are considered essential to assist adults in achieving instructional goals and objectives. Following the listing a brief justification and examples of ways to evaluate teacher competencies are discussed. (Author/BP)

  16. Recruiting Adult Education Students.

    ERIC Educational Resources Information Center

    Learning Resources Network, Manhattan, KS.

    This document is the first nationwide compilation of successful recruiting techniques for students in adult basic education, literacy, General Educational Development classes, and adult high school degree programs. Information for the publication was gathered from a literature search and other sources, especially "Reaching the Least Educated," a…

  17. Counseling Adult Adoptees

    ERIC Educational Resources Information Center

    Corder, Kate

    2012-01-01

    This review presents various resources about working with adult adoptees in order to inform counselors in their practice. Topics covered include basics of adoption, including types of adoption and adoption statistics; possible issues adult adoptees may face; and suggestions and implications for counselors. The article addresses some of the serious…

  18. Adult Education and Development.

    ERIC Educational Resources Information Center

    Hinzen, Heribert, Ed.

    2002-01-01

    This document contains 19 papers on adult education and development worldwide. The following papers are included: "Editorial" (Heribert Hinzen); "Lifelong Learning in Europe: Moving towards EFA (Dakar Framework for Action on Education for All) Goals and the CONFINTEA V Agenda" (Sofia Conference on Adult Education); "Poverty and Schooling in the…

  19. Adult Day Services

    MedlinePlus

    A Smart Choice Adult Day Services Comparison At-a-Glance 1 Adult Day Services Assisted Living Home Care Nursing Homes Live at home with family ... supervision Nursing care available as needed during the day Flexibility to receive care only on days when ...

  20. Today's Adult Students

    ERIC Educational Resources Information Center

    Reese, Susan

    2012-01-01

    Who are the adult students in career and technical education (CTE) today? There is not one simple answer to that question. Some are young with little life experience, while others are returning to the workforce and learning new skills to reinvent themselves. Whatever the case, educating adult students is an integral part of ACTE's mission, and the…