14 resultados para STRAND BREAKS

em Aquatic Commons


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The alkaline comet assay is a method of detecting DNA strand breaks and alkali labile sites in individual cells. The method was used to detect DNA strand breaks in isolated blood cells (leukocytes) of carp (Cyprius carpio). DNA damage have been induced by exposure of the cells to sediment extract. Therefore comet assay can be applied as in vitro bioassay for investigations on toxicity of marine sediments.

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For the first time in its history, the International Symposium on Sea Turtle Biology and Conservation migrated to a site outside of the United States. Thus the Eighteenth edition was hosted by the Mazatlán Research Unit of the Instituto de Ciencias del Mar y Limnología of the Mexican National Autonomous University (UNAM) in Mazatlán, Sinaloa (Mexico) where it was held from 3-7, March, 1998. Above all, our symposium is prominent for its dynamism and enthusiasm in bringing together specialists from the world´s sea turtle populations. In an effort to extend this philosophy, and fully aware of how fast the interest in sea turtles has grown, the organizers paid special attention to bring together as many people as possible. With the tremendous efforts of the Travel Committee and coupled with a special interest by the Latin American region´s devotees, we managed to get 653 participants from 43 countries. The number of presentations increased significantly too, reaching a total of 265 papers, ranging from cutting-edge scientific reports based on highly sophisticated methods, to the experiences and successes of community-based and environmental education programs. A priority given by this symposium was the support and encouragement for the construction of "bridges" across cultural and discipline barriers. We found success in achieving a multinational dialogue among interest groups- scientists, resource managers, decision makers, ngo's, private industry. There was a broad representation of the broad interests that stretch across these sectors, yet everyone was able to listen and offer their own best contribution towards the central theme of the Symposium: the conservation of sea turtles and the diversity of marine and coastal environments in which they develop through their complicated and protracted life cycle. Our multidisciplinary approach is highly important at the present, finding ourselves at a cross roads of significant initiatives in the international arena of environmental law, where the conservation of sea turtles has a key role to play. Many, many people worked hard over the previous 12 months, to make the symposium a success. Our sincerest thanks to all of them: Program committee: Laura Sarti (chair), Ana Barragán, Rod Mast, Heather Kalb, Jim Spotilla, Richard Reina, Sheryan Epperly, Anna Bass, Steve Morreale, Milani Chaloupka, Robert Van Dam, Lew Ehrhart, J. Nichols, David Godfrey, Larry Herbst, René Márquez, Jack Musick, Peter Dutton, Patricia Huerta, Arturo Juárez, Debora Garcia, Carlos Suárez, German Ramírez, Raquel Briseño, Alberto Abreu; Registration and Secretary: Jane Provancha (chair), Lupita Polanco; Informatics: Germán Ramírez, Carlos Suárez; Cover art: Blas Nayar; Designs: Germán Ramírez, Raquel Briseño, Alberto Abreu. Auction: Rod Mast; Workshops and special meetings: Selina Heppell; Student prizes: Anders Rhodin; Resolutions committee: Juan Carlos Cantú; Local organizing committee: Raquel Briseño, Jane Abreu; Posters: Daniel Ríos and Jeffrey Semminoff; Travel committee: Karen Eckert (chair), Marydele Donnelly, Brendan Godley, Annette Broderick, Jack Frazier; Student travel: Francisco Silva and J. Nichols; Vendors: Tom McFarland and J. Nichols; Volunteer coordination: Richard Byles; Latin American Reunión: Angeles Cruz Morelos; Nominations committee: Randall Arauz, Colleen Coogan, Laura Sarti, Donna Shaver, Frank Paladino. Once again, Ed Drane worked his usual magic with the Treasury of the Symposium Significant financial contributions were generously provided by government agencies. SEMARNAP (Mexico´s Ministry of Environment, Natural Resources and Fisheries) through its central office, the Mazatlán Regional Fisheries Research Center (CRIP-Mazatlán) and the National Center for Education and Capacity Building for Sustainable Development (CECADESU) contributed to the logistics and covered the costs of auditoria and audiovisual equipment for the Symposium, teachers and their hotels for the Community Development and Environmental Education workshop in the 5th Latin American Sea Turtle Specialists; DIF (Dept of Family Affairs) provided free accomodation and food for the more than 100 participants in the Latin American Reunion. In this Reunion, the British Council-Mexico sponsored the workshop on the Project Cycle. The National Chamber of the Fisheries Industry (CANAINPES) kindly sponsored the Symposium´s coffee breaks. Personnel from the local Navy (Octave Zona Naval) provided invaluable aid in transport and logistics. The Scientific Coordination Office from UNAM (CICUNAM) and the Latin American Biology Network (RELAB) also provided funding. Our most sincere recognition to all of them. In the name of this Symposium´s compilers, I would like to also express our gratitude to Wayne Witzell, Technical Editor for his guidance and insights and to Jack Frazier for his help in translating and correcting the English of contributions from some non-native English speakers. Many thanks to Angel Fiscal and Tere Martin who helped with the typing in the last, last corrections and editions for these Proceedings. To all, from around the world, who generously helped make the 18th Symposium a huge success, shared their experiences and listened to ours, our deepest gratitude! (PDF contains 316 pages)

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Information on geographical variation is reviewed for Stenella attenuata, S. longirostris, S. coeruleoalba, and Delphinus delphis in the eastern tropical Pacific, and boundaries for potential management units are proposed. National Marine Fisheries Service and Inter-American Tropical Tuna Commission sighting records made from 1979 to 1983 which were outside boundaries used in a 1979 assessment were examined for validity. Tagging returns and morphological data were also analyzed. Several stock ranges are expanded or combined. Three management units are proposed for S. attenuata: the coastal, northern offshore, and southern offshore spoiled dolphins. Four management units are proposed for S. longirostris: the Costa Rican, eastern, northern whitebelly, and southern whitebelly spinner dolphins. Two provisional management units are proposed for S. coeruleoalba: the northern and southern striped dolphins. Five management units (two of which are provisional) are proposed for D. delphis: the Baja neritic, northern, central, southern, and Guerrero common dolphins. Division into management units was based on morphological stock differences and distributional breaks. (PDF file contains 34 pages.)

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The Symposium in which the communications, as they were called during the meeting, comprising this volume were presented was held at the Zoological Institute of the Academy of Sciences of the U.S.S.R. in Leningrad during 13 to 16 October 1981. Conducted as part of the cooperative program of the U.S.A.-U.S.S.R. Working Group on Biological Productivity and Biochemistry of the World Ocean, the Leningrad meeting was sponsored by the Academy of Sciences of the U.S.S.R. (the Zoological Institute) and the Ministry of Fisheries of the U.S.S.R. (The Scientific Council on Fish Diseases of the Ichthyological Commission). It was an extremely interesting and successful Symposium, offering all participants the opportunity to describe the results of their studies and reviews during the course of the formal presentations and direct interchange between scientists during breaks in the program and the organized and casual social activities. The facilities provided by the Zoological Institute were quite adequate and the assistance offered by its Director, O. A. Scarlato and his staff in organization,logistics, and translation was excellent. Several of our Soviet colleagues presided over the proceedings, as did I. All were businesslike and efficient, yet graceful and accommodating. To O. N. Bauer Jell the brunt of programmatic detail and follow-up. He bore his burdens well and, with Director Scarlato and his staff, including A. V. Gussev and others of the professional and technical staffs of the Zoological Institute, helped make our stay pleasant and the Symposium productive. These organizations and individuals deserve much credit and praise as well as the thanks of their American and British colleagues. (PDF file contains 141 pages.)

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The nearshore waters along the Myrtle Beach area are oceanographically referred to as Long Bay. Long Bay is the last in a series of semi-circular indentations located along the South Atlantic seaboard. The Bay extends for approximately 150 km from the Cape Fear River in North Carolina to Winyah Bay in South Carolina and has a number of small inlets (Figure 1). This region of the S.C. coast, commonly referred to as the “Grand Strand,” has a significant tourism base that accounts for a substantial portion of the South Carolina economy (i.e., 40% of the state’s total in 2002) (TIAA 2003). In 2004, the Grand Strand had an estimated 13.2 million visitors of which 90% went to the beach (MBCC 2006). In addition, Long Bay supports a shore-based hook and line fishery comprised of anglers fishing from recreational fishing piers, the beach, and small recreational boats just offshore. (PDF contains 4 pages)

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DNA in canned tuna is degraded into short fragments of a rew hundred base pairs. The polymerase chain reaction (PCR) was used to amplify short sequences of mitochondrial DNA, which were denatured and analysed by polyacrylamide gel electrophoresis (native PAGE) for detection of single strand conformation polymorphisms. Species specific patterns of DNA bands were obtained for a number of tuna and bonito species. DE: In Thunfischkonserven liegt die DNA in Form kurzkettiger Fragmente von wenigen Hundert Basenpaaren Länge vor. Mit Hilfe der Polymerase-Kettenreaktion (PCR) wurden kurze Sequenzen der mitochondrialen DNA vervielfältigt. Anschließend wurde die gebildete DNA in Einzelsträngen überführt, die durch eine native Polyacrylamidgel-Elektrophorese (PAGE) aufgetrennt wurde. Für eine Reihe von Thunfischen und Boniten ergaben die Einzelstränge artspezifische Bandenmuster, die auf unterschiedliche Konformationen der DNA-Stränge der einzelnen Fischarten zurückzuführen sind.

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As the atmospheric levels of CO2 rise from human activity, the carbonic acid levels of the ocean increase, causing ocean acidification. This increase in acidity breaks down the calcified bodies that many marine organisms depend upon. Upwelling regions such as Monterey Bay in California have pH levels that are not expected to reach the open ocean for a few decades. This study reviews one of the common intertidal animals of the California coast, the Owl Limpet Lottia gigantea, and its genetic variation of the plasma membrane Ca2+ ATPase (PMCA) in relation to the acidity of its environment. The PMCA protein functions in the calcification process of many organisms. Specifically in limpets, this gene functions to form its protective shell. Single-nucleotide polymorphisms (SNPs) were found among five sections of the gene to determine variation between the acidic environment population in Monterey, California and the non-acidic environment population in Santa Barbara, California. While some variation was determined, the Monterey Bay and Santa Barbara Lottia gigantea populations are not significantly distinct at the PMCA gene. Sections B, C, and D were found to be linked. Only one location in Section B was found to have an amino acid change within an exon. Section A has the strongest connection to the sampling location. Monterey individuals were seen to be more genetically recognizable, while Santa Barbara individuals showed slightly more variation. Understanding the trends of ocean acidification, upwelling region activities, and population genetics will assist in determining how the ocean environment will behave in the future.

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The procedures described are standard methods used in the European Union to quantify wood quality. Samples used here were smaller than the standards laid down in the DIN system (12 x 12 x 16 cm) as Litsea is a small tree and planks of the required size are unobtainable. The use of quality sized samples means that the results presented here can be compared with each other but unfortunately not with data in the literature. Wood is dried first at ambient temperature in the shade to reduce moisture content to an even 11-12%. Part of the sample was then oven-dried to 0% moisture content and its specific density determined by weighing a subsample of 128 cm super(3) (4 x 4 x 8 cm). Strength of expansion of the wood is determined as the percentage by which the wood sample can be pulled apart parallel and vertical to the grain before it breaks. Compression and bending strengths and elasticity are measured by compressing, bending and pulling wood sample in a machine specially designedto determine the forces required.

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The foraging ecology of bottlenose dolphins Tursiops truncatus in the Northwest Florida Panhandle and estuaries in northern Georgia was determined using diet analysis and behavioral surveys. Stomach content analysis was completed on bottlenose dolphins(N = 25) that stranded in the Northwest Florida Panhandle from November 2006 to March 2009. The most abundant prey species were spot Leiostomus xanthurus (20.4%), squid (10.9%), pinfish Lagodon rhombiodes (10.3%), and Atlantic croaker Micropogonias undulatus (8.5%). Dolphins that stranded during months with a red tide Karenia brevis bloom consumed more pinfish, and spot; whereas dolphins that stranded in non-bloom months consumed more squid, Atlantic croaker, and silver perch Bairdiella chrysoura. Differences in diet were also identified for dolphins that stranded inside bays/sound and dolphin that stranded outside of bays along the coast, and male and female dolphins. Surveys were conducted from south of the Savannah River to north of Ossabaw Sound in Georgia where foraging behaviors were classified. Multivariate Generalized Additive Models were used to test correlations of behaviors to dolphin group size, depth, salinity, temperature, creek width, and tide. Sightings with headstands (p = 0.009), hard stops (p = 0.019), chasing (p = 0.004), mudbank whacking (p < 0.001), herding/circling (p = 0.024), and strand feeding (p = 0.006) were correlated with shallow water or small creeks. Sightings with kerplunking (p = 0.031), mudbank whacking (p = 0.001), strand feeding (p = 0.003), and herding/circling (p = 0.026) were significantly correlated with low tide. The results of the Savannah, Georgia study were the first to characterize foraging behaviors in this area and demonstrate how bottlenose dolphins utilize the salt marsh estuary in terms of foraging. Studies like these are important to determine how dolphins forage efficiently and to provide background information on diet and foraging behavior for use in monitoring future impacts to dolphins in the Northwest Florida Panhandle and near Savannah, Georgia.

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To ensure the authentication of fishery products lacking biological characters, rapid species identification methods are required. Two DNA- and protein-based methods, PCR-SSCP (polymerase chain reaction - single strand conformation polymorphism) of a 464 bp segment of the cytochrome b – gene and isoelectric focusing (IEF) of water-soluble proteins from fish fillets, were applied to identify fillets of (sub-) tropical fish species available on the European market. Among the samples analysed were two taxonomically identified species from the family Sciaenidae and one from Sphyraenidae. By comparison of DNA- and protein patterns of different samples, information about intra-species variability of patterns, and homogeneity of batches (e.g. fillet blocks or bags) can be obtained. PCR-SSCP and IEF may be useful for pre-checking of a large number of samples by food control laboratories. Zusammenfassung Zur Sicherstellung der Authentizität von Fischerei-Erzeugnissen ohne biologische Merkmale sind schnelle Verfahren zur Speziesidentifizierung hilfreich. Zwei Methoden der DNA- bzw. Protein-Analyse wurden eingesetzt, um Filets (sub-) tropischer Fischarten, die auf dem europäischen Markt angeboten werden, zu identifizieren. Bei diesen Methoden handelt es sich um die PCR-SSCP (Polymerase-Kettenreaktion – Einzelstrang-Konformationspolymorphismus) – Analyse der PCR-Produkte und die IEF (isoelektrische Fokussierung) der wasserlöslichen Fischmuskelproteine. Unter den untersuchten Proben waren zwei taxonomisch bestimmte Arten aus der Familie Sciaenidae und eine Spezies aus der Familie Sphyraenidae. Durch Vergleich der DNA- bzw. Proteinmuster lassen sich Informationen über die intra-spezifische Variabilität solcher Muster und die Einheitlichkeit von Partien (beispielsweise Filetblöcke oder Filetbeutel) gewinnen. PCR-SSCP und IEF können in Laboratorien der Lebensmittelüberwachung als Vortest gerade bei hohen Probenzahlen sinnvoll eingesetzt werden.

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Numerous studies have applied skeletochronology to sea turtle species. Because many of the studies have lacked validation, the application of this technique to sea turtle age estimation has been called into question. To address this concern, we obtained humeri from 13 known-age Kemp’s ridley (Lepidochelys kempii) and two loggerhead (Caretta caretta) sea turtles for the purposes of examining the growth marks and comparing growth mark counts to actual age. We found evidence for annual deposition of growth marks in both these species. Corroborative results were found in Kemp’s ridley sea turtles from a comparison of death date and amount of bone growth following the completion of the last growth mark (n=76). Formation of the lines of arrested growth in Kemp’s ridley sea turtles consistently occurred in the spring for animals that strand dead along the mid- and south U.S. Atlantic coast. For both Kemp’s ridley and loggerhead sea turtles, we also found a proportional allometry between bone growth (humerus dimensions) and somatic growth (straight carapace length), indicating that size-at-age and growth rates can be estimated from dimensions of early growth marks. These results validate skeletochronology as a method for estimating age in Kemp’s ridley and loggerhead sea turtles from the southeast United States.

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Sea turtles are subjected to involuntary submergence and potential mortality due to incidental capture by the commercial shrimp fishing industry. Despite implementation of turtle excluder devices (TEDs) to reduce at-sea mortality, dead stranded turtles continue to be found in near-record numbers along the coasts of the western Atlantic Ocean and northern Gulf of Mexico. Although this mortality may be due to an increase in the number of turtles available to strand, one alternative explanation is that sea turtles are repetitively submerged (as one fishing vessel follows the path of another) in legal TEDs. In the present study, laboratory and field investigations were undertaken to examine the physiological effects of multiple submergence of loggerhead sea turtles (Caretta caretta). Turtles in the laboratory study were confined during the submersion episodes, whereas under field conditions, turtles were released directly into TED-equipped commercial fishing nets. Under laboratory and field conditions, pre- and postsubmergence blood samples were collected from turtles submerged three times at 7.5 min per episode with an in-water rest interval of 10, 42, or 180 min between submergences. Analyses of pre- and postsubmergence blood samples revealed that the initial submergence produced a severe and pronounced metabolic and respiratory acidosis in all turtles. Successive submergences produced significant changes in blood pH, Pco2, and lactate, although the magnitude of the acid-base imbalance was substantially reduced as the number of submergences increased. In addition, increasing the interval between successive submergences permitted greater recovery of blood homeostasis. No turtles died during these studies. Taken together, these data suggest that repetitive sub-mergence of sea turtles in TEDs would not significantly affect their survival potential provided that the animal has an adequate rest interval at the surface between successive submergences.

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The Lake Kyoga complex lies towards the north of Uganda, at 311 altitude of 3,400 feet, between 10 and 2° north of the Equator. The lake is extremely elongate and digitate, shallow (1 metre-7 metres), and almost all the coast-line is swampy, with many papyrus beds. Floating islands of sud are a feature. At its eastern extremity, it breaks up into many swampy, isolated lakes. The Nile from its source at Jinja enters Lake Kyoga on its southern side, and leaves the lake at its western extremity, and winds on through to Lake Albert and the Sudan. The Kyoga/Salisbury /Kwania complex covers 2,354 sq. km. of water. Geologically, the lake is a series of flooded river valleys, probably resulting from the uplifting of the western edge of the basin in the Pliocene and the Pleistocene ages aud the endemic fish fauna is very similar to that of Lake Victoria, although Kyoga has not developed the species flocks of haplochromis which characterise the larger lake. The Victoria fauna extends down-stream of Lake Kyoga to the Murchison Falls on the Nile, which forms an almost complete barrier between Kyoga and the typical nilotic fauna of the Nile below Murchison and Lake Albert.