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Sample records for determining lamprey species

  1. Determining Lamprey Species Composition, Larval Distribution and Adult Abundance in the Deschutes River Subbasin, Oregon ; 2007 Annual Report.

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    Fox, Matt; Graham, Jennifer C. [Department of Natural Resources, Confederated Tribes of the Warm Springs Reservation, Oregon

    2009-06-26

    We will report results of an ongoing project in the Deschutes River Subbasin to describe Pacific lamprey (Lampetra tridentata) life history. Project objectives were to determine adult lamprey escapement from Sherars Falls located at Rkm 70.4 and determine lamprey focal spawning areas, spawn timing and habitat through radio telemetry. A mark-recapture study and tribal creel was conducted to determine adult escapement. Lamprey were radio tagged and are currently being mobile, aerial and fixed site tracked to describe spawning. Adult lamprey were collected at Sherars Falls using a long-handled dip net from June-September 2007. The fate of lamprey collected at Sherars Falls was determined based on girth measurements. Fish measuring less than 10.5 cm received two markings for the mark-recapture estimation while those measuring 10.5 cm or greater were implanted with radio transmitters. Two-hundred and nine lamprey were marked during first event sampling, 2,501 lamprey inspected for marks and 64 recaptured during second event sampling. We estimate lamprey abundance to be 8,083 (6,352-10,279) with a relative precision of 19.8. Tribal harvest was 2,303 +/- 88. Escapement was estimated at 5,780 adult lamprey. Thirty-six lamprey received radio transmitters. Lamprey were transported upstream 6.3 Rkm for surgery, held to recover from anesthesia and released. Mobile tracking efforts started mid-July 2007 and are on-going. To date 35 of the 36 lamprey have been detected. Upon release, extensive ground-based tracking was conducted until fish became dormant in mid-October. Since, fixed site downloading and tracking have occurred weekly on the mainstem Deschutes River. Majority of lamprey (88%) are holding in the mainstem Deschutes River. Three lamprey moved upstream more than 70 Rkms into westside tributaries from August-December. Three moved approximately 18 Rkms downstream of the release site. Tracking will continue through the spawning season when redd characteristics will be

  2. Comparison of synthesis of 15α-hydroxylated steroids in males of four North American lamprey species

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    Bryan, Mara B.; Young, Bradley A.; Close, David A.; Semeyn, Jesse; Robinson, T. Craig; Bayer, Jennifer M.; Li, Weiming

    2006-01-01

    Recent studies have provided evidence that 15α-hydroxytestosterone (15α-T) and 15α-hydroxyprogesterone (15α-P) are produced in vitro and in vivo in adult male sea lampreys (Petromyzonmarinus), and that circulatory levels increase in response to injections with gonadotropin-releasing hormone (GnRH). We examined four species from the Petromyzontidae family including silver lampreys (Ichthyomyzon unicuspis), chestnut lampreys (I. castaneus), American brook lampreys (Lethenteron appendix), and Pacific lampreys (Entosphenus tridentatus) to determine if these unusual steroids were unique to sea lampreys or a common feature in lamprey species. In vitro production was examined through incubations of testis with tritiated precursors, and 15α-T and 15α-P production was confirmed in all species through co-elution with standards on both high performance liquid chromatography (HPLC) and thin layerchromatography. In vivo production was proven by demonstrating that HPLC-fractionated plasma had peaks of immunoreactive 15α-T and 15α-P that co-eluted with standards through using previously developed radioimmunoassays for 15α-T and 15α-P. The possible functionality of 15α-T and 15α-P was further examined in silver and Pacific lampreys by investigating the effect of injection of either type of lamprey GnRH on plasma concentrations of 15α-T and 15α-P. Injections with exogenous GnRH did not affect circulatory levels of either steroid in silver lampreys, and only GnRH III elicited higher levels of both steroids in Pacific lampreys. The 15α-hydroxylase enzyme(s) for steroids appeared to present in adult males of all species examined, but the question of whether 15α-hydroxylated steroids are functional in these lamprey species, and the significance of the 15-hydroxyl group, requires further research.

  3. Characterization of 12 microsatellite loci for the Pacific lamprey, Entosphenus tridentatus (Petromyzontidae), and cross-amplification in five other lamprey species.

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    Spice, E K; Whitesel, T A; McFarlane, C T; Docker, M F

    2011-12-22

    The Pacific lamprey (Entosphenus tridentatus) is an anadromous fish that is of conservation concern in North America and Asia. Data on Pacific lamprey population structure are scarce and conflicting, impeding conservation efforts. We optimized 12 polymorphic microsatellite loci for the Pacific lamprey. Three to 13 alleles per locus were observed in a sample of 51 fish collected from the West Fork Illinois River, Oregon. Observed heterozygosity ranged from 0.235 to 0.902 and expected heterozygosity ranged from 0.214 to 0.750. Cross-species amplification produced 8 to 12 polymorphic loci in four other Entosphenus species and in the western brook lamprey (Lampetra richardsoni). Two loci appear to be diagnostic for distinguishing Entosphenus from Lampetra. These markers will be valuable for evaluating population structure and making conservation decisions for E. tridentatus and other lamprey species.

  4. Reproductive ecology of lampreys

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    Johnson, Nicholas S.; Buchinger, Tyler J.; Li, Weiming

    2014-01-01

    Lampreys typically spawn in riffle habitats during the spring. Spawning activity and diel (i.e., during daylight and at night) behavioral patterns are initiated when spring water temperatures increase to levels that coincide with optimal embryologic development. Nests are constructed in gravel substrate using the oral disc to move stones and the tail to fan sediment out of the nest. Spawning habitat used by individual species is generally a function of adult size, where small-bodied species construct nests in shallower water with slower flow and smaller gravel than large-bodied species. The mating system of lampreys is primarily polygynandrous (i.e., where multiple males mate with multiple females). Lamprey species with adult total length less than 30 cm generally spawn communally, where a nest may contain 20 or more individuals of both sexes. Lamprey species with adult sizes greater than 35 cm generally spawn in groups of two to four. Operational sex ratios of lampreys are highly variable across species, populations, and time, but are generally male biased. The act of spawning typically starts with the male attaching with his oral disc to the back of the female’s head; the male and female then entwine and simultaneously release gametes. However, alternative mating behaviors (e.g., release of gametes without paired courtship and sneaker males) have been observed. Future research should determine how multiple modalities of communication among lampreys (including mating pheromones) are integrated to inform species recognition and mate choice. Such research could inform both sea lamprey control strategies and provide insight into possible evolution of reproductive isolation mechanisms between paired lamprey species in sympatry.

  5. Olfactory sensitivity of Pacific Lampreys to lamprey bile acids

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    Robinson, T. Craig; Sorensen, Peter W.; Bayer, Jennifer M.; Seelye, James G.

    2009-01-01

    Pacific lampreys Lampetra tridentata are in decline throughout much of their historical range in the Columbia River basin. In support of restoration efforts, we tested whether larval and adult lamprey bile acids serve as migratory and spawning pheromones in adult Pacific lampreys, as they do in sea lampreys Petromyzon marinus. The olfactory sensitivity of adult Pacific lampreys to lamprey bile acids was measured by electro-olfactogram recording from the time of their capture in the spring until their spawning in June of the following year. As controls, we tested L-arginine and a non-lamprey bile acid, taurolithocholic acid 3-sulfate (TLS). Migrating adult Pacific lampreys were highly sensitive to petromyzonol sulfate (a component of the sea lamprey migratory pheromone) and 3-keto petromyzonol sulfate (a component of the sea lamprey sex pheromone) when first captured. This sensitivity persisted throughout their long migratory and overwinter holding period before declining to nearly unmeasurable levels by the time of spawning. The absolute magnitudes of adult Pacific lamprey responses to lamprey bile acids were smaller than those of the sea lamprey, and unlike the sea lamprey, the Pacific lamprey did not appear to detect TLS. No sexual dimorphism was noted in olfactory sensitivity. Thus, Pacific lampreys are broadly similar to sea lampreys in showing sensitivity to the major lamprey bile acids but apparently differ in having a longer period of sensitivity to those acids. The potential utility of bile acid-like pheromones in the restoration of Pacific lampreys warrants their further investigation in this species.

  6. Rapid evolution meets invasive species control: The potential for pesticide resistance in sea lamprey

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    Dunlop, Erin S.; McLaughlin, Robert L.; Adams, Jean V.; Jones, Michael L.; Birceanu, Oana; Christie, Mark R.; Criger, Lori A.; Hinderer, Julia L.M.; Hollingworth, Robert M.; Johnson, Nicholas; Lantz, Stephen R.; Li, Weiming; Miller, James R.; Morrison, Bruce J.; Mota-Sanchez, David; Muir, Andrew M.; Sepulveda, Maria S.; Steeves, Todd B.; Walter, Lisa; Westman, Erin; Wirgin, Isaac; Wilkie, Michael P.

    2018-01-01

    Rapid evolution of pest, pathogen and wildlife populations can have undesirable effects; for example, when insects evolve resistance to pesticides or fishes evolve smaller body size in response to harvest. A destructive invasive species in the Laurentian Great Lakes, the sea lamprey (Petromyzon marinus) has been controlled with the pesticide 3-trifluoromethyl-4-nitrophenol (TFM) since the 1950s. We evaluated the likelihood of sea lamprey evolving resistance to TFM by (1) reviewing sea lamprey life history and control; (2) identifying physiological and behavioural resistance strategies; (3) estimating the strength of selection from TFM; (4) assessing the timeline for evolution; and (5) analyzing historical toxicity data for evidence of resistance. The number of sea lamprey generations exposed to TFM was within the range observed for fish populations where rapid evolution has occurred. Mortality from TFM was estimated as 82-90%, suggesting significant selective pressure. However, 57 years of toxicity data revealed no increase in lethal concentrations of TFM. Vigilance and the development of alternative controls are required to prevent this aquatic invasive species from evolving strategies to evade control.

  7. Population ecology of the sea lamprey (Petromyzon marinus) as an invasive species in the Laurentian Great Lakes and an imperiled species in Europe

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    Hansen, Michael J.; Madenjian, Charles P.; Slade, Jeffrey W.; Steeves, Todd B.; Almeida, Pedro R.; Quintella, Bernardo R.

    2016-01-01

    The sea lamprey Petromyzon marinus (Linnaeus) is both an invasive non-native species in the Laurentian Great Lakes of North America and an imperiled species in much of its native range in North America and Europe. To compare and contrast how understanding of population ecology is useful for control programs in the Great Lakes and restoration programs in Europe, we review current understanding of the population ecology of the sea lamprey in its native and introduced range. Some attributes of sea lamprey population ecology are particularly useful for both control programs in the Great Lakes and restoration programs in the native range. First, traps within fish ladders are beneficial for removing sea lampreys in Great Lakes streams and passing sea lampreys in the native range. Second, attractants and repellants are suitable for luring sea lampreys into traps for control in the Great Lakes and guiding sea lamprey passage for conservation in the native range. Third, assessment methods used for targeting sea lamprey control in the Great Lakes are useful for targeting habitat protection in the native range. Last, assessment methods used to quantify numbers of all life stages of sea lampreys would be appropriate for measuring success of control in the Great Lakes and success of conservation in the native range.

  8. HPLC and ELISA analyses of larval bile acids from Pacific and western brook lampreys

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    Yun, S.-S.; Scott, A.P.; Bayer, J.M.; Seelye, J.G.; Close, D.A.; Li, W.

    2003-01-01

    Comparative studies were performed on two native lamprey species, Pacific lamprey (Lampetra tridentata) and western brook lamprey (Lampetra richardsoni) from the Pacific coast along with sea lamprey (Petromyzon marinus) from the Great Lakes, to investigate their bile acid production and release. HPLC and ELISA analyses of the gall bladders and liver extract revealed that the major bile acid compound from Pacific and western brook larval lampreys was petromyzonol sulfate (PZS), previously identified as a migratory pheromone in larval sea lamprey. An ELISA for PZS has been developed in a working range of 20pg-10ng per well. The tissue concentrations of PZS in gall bladder were 127.40, 145.86, and 276.96??g/g body mass in sea lamprey, Pacific lamprey, and western brook lamprey, respectively. Releasing rates for PZS in the three species were measured using ELISA to find that western brook and sea lamprey released PZS 20 times higher than Pacific lamprey did. Further studies are required to determine whether PZS is a chemical cue in Pacific and western brook lampreys. ?? 2003 Elsevier Inc. All rights reserved.

  9. Determining Adult Pacific Lamprey Abundance and Spawning Habitat in the Lower Deschutes River Sub-Basin, Oregon, 2008 Annual Report.

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    Fox, Matt; Graham, Jennifer C. [Confederated Tribes of the Warm Springs Reservation, Oregon

    2009-04-30

    An adult Pacific lamprey (Lampetra tridentata) escapement estimate was generated in the lower Deschutes River during run year 2008. This included a mark-recapture study to determine adult abundance and a tribal subsistence creel. Fish measuring less than 10.5 cm received two marks for the mark-recapture estimate while those measuring greater than 10.5 cm were surgically implanted with radio transmitters to monitor migration upstream of Sherars Falls (rkm 70.4). Radio telemetry was used to determine habitat, focal spawning areas and spawn timing. All fish were collected at the Sherars Falls fish ladder from July-October 2008 using a long handled dip-net. Escapement was generated using a two event mark-recapture experiment. Adult lamprey populations were estimated at 3,471 (95% CI = 2,384-5,041; M = 101; C = 885 R = 25) using Chapman's modification of the Peterson estimate. The relative precision around the estimate was 31.42. Tribal harvest was approximately 806 adult lamprey (95% CI = +/- 74) with a total escapement of 2,669. Fourteen lamprey received radio tags and were released at Lower Blue Hole recreation site (rkm 77.3). Movement was recorded by mobile, fixed site and aerial telemetry methods. Upstream movements of lamprey were documented from July through December 2008 with most lamprey over-wintering in the mainstem Deschutes River.

  10. Population genomics of Pacific lamprey: adaptive variation in a highly dispersive species.

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    Hess, Jon E; Campbell, Nathan R; Close, David A; Docker, Margaret F; Narum, Shawn R

    2013-06-01

    Unlike most anadromous fishes that have evolved strict homing behaviour, Pacific lamprey (Entosphenus tridentatus) seem to lack philopatry as evidenced by minimal population structure across the species range. Yet unexplained findings of within-region population genetic heterogeneity coupled with the morphological and behavioural diversity described for the species suggest that adaptive genetic variation underlying fitness traits may be responsible. We employed restriction site-associated DNA sequencing to genotype 4439 quality filtered single nucleotide polymorphism (SNP) loci for 518 individuals collected across a broad geographical area including British Columbia, Washington, Oregon and California. A subset of putatively neutral markers (N = 4068) identified a significant amount of variation among three broad populations: northern British Columbia, Columbia River/southern coast and 'dwarf' adults (F(CT) = 0.02, P ≪ 0.001). Additionally, 162 SNPs were identified as adaptive through outlier tests, and inclusion of these markers revealed a signal of adaptive variation related to geography and life history. The majority of the 162 adaptive SNPs were not independent and formed four groups of linked loci. Analyses with matsam software found that 42 of these outlier SNPs were significantly associated with geography, run timing and dwarf life history, and 27 of these 42 SNPs aligned with known genes or highly conserved genomic regions using the genome browser available for sea lamprey. This study provides both neutral and adaptive context for observed genetic divergence among collections and thus reconciles previous findings of population genetic heterogeneity within a species that displays extensive gene flow. © 2012 John Wiley & Sons Ltd.

  11. Evaluate Status of Pacific Lamprey in the Clearwater River Drainage, Idaho: Annual Report 2001.

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    Cochnauer, Tim; Claire, Christopher

    2002-12-01

    Recent decline of Pacific lamprey Lampetra tridentata adult migrants to the Snake River drainage has focused attention on the species. Adult Pacific lamprey counted passing Ice Harbor Dam fishway averaged 18,158 during 1962-69 and 361 during 1993-2000. Human resource manipulations in the Snake River and Clearwater River drainages have altered ecosystem habitat in the last 120 years, likely impacting the productive potential of Pacific lamprey habitat. Timber harvest, stream impoundment, road construction, grazing, mining, and community development have dominated habitat alteration in the Clearwater River system and Snake River corridor. Hydroelectric projects in the Snake River corridor impact juvenile/larval Pacific lamprey outmigrants and returning adults. Juvenile and larval lamprey outmigrants potentially pass through turbines, turbine bypass/collection systems, and over spillway structures at the four lower Snake River hydroelectric dams. Clearwater River drainage hydroelectric facilities have impacted Pacific lamprey populations to an unknown degree. The Pacific Power and Light Dam on the Clearwater River in Lewiston, Idaho, restricted chinook salmon Oncorhynchus tshawytscha passage in the 1927-1940 period, altering the migration route of outmigrating Pacific lamprey juveniles/larvae and upstream adult migrants (1927-1972). Dworshak Dam, completed in 1972, eliminated Pacific lamprey spawning and rearing in the North Fork Clearwater River drainage. Construction of the Harpster hydroelectric dam on the South Fork of the Clearwater River resulted in obstructed fish passage 1949-1963. Through Bonneville Power Administration support, the Idaho Department of Fish and Game continued investigation into the status of Pacific lamprey populations in Idaho's Clearwater River drainage in 2001. Trapping, electrofishing, and spawning ground redd surveys were used to determine Pacific lamprey distribution, life history strategies, and habitat requirements in the South

  12. Ecological and Cultural Importance of a Species at Risk of Extinction, Pacific Lamprey, 1964-2002 Technical Report.

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    Close, David A.

    2002-07-01

    The cultural and ecological values of Pacific lamprey (Lampetra tridentata) have not been understood by Euro-Americans and thus their great decline has almost gone unnoticed except by Native Americans, who elevated the issue and initiated research to restore its populations, at least in the Columbia Basin. They regard Pacific lamprey as a highly valued resource and as a result ksuyas (lamprey) has become one of their cultural icons. Ksuyas are harvested to this day as a subsistence food by various tribes along the Pacific coast and are highly regarded for their cultural value. Interestingly, our review suggests that the Pacific lamprey plays an important role in the food web, may have acted as a buffer for salmon from predators, and may have been an important source of marine nutrients to oligotrophic watersheds. This is very different from the Euro-American perception that lampreys are pests. We suggest that cultural biases affected management policies.

  13. Variations in the presence of chloride cells in the gills of lampreys (Petromyzontiformes) and their evolutionary implications.

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    Bartels, H; Docker, M F; Krappe, M; White, M M; Wrede, C; Potter, I C

    2015-04-01

    Although confined to fresh water, non-parasitic species of lampreys and the landlocked parasitic sea lamprey, all of which were derived relatively recently from an adromous ancestors, still develop chloride cells, whose function in their ancestors was for osmoregulation in marine waters during the adult parasitic phase. In contrast, such cells are not developed by the non-parasitic least brook lamprey Lampetra aepyptera, which has been separated from its ancestor for >2 million years, nor by the freshwater parasitic species of the genus Ichthyomyzon. The length of time that a non-parasitic species or landlocked parasitic form or species has spent in fresh water is thus considered the overriding factor determining whether chloride cells are developed by those lampreys.

  14. Use of chemosensory cues as repellents for sea lamprey: Potential directions for population management

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    Imre, I.; Brown, G.E.; Bergstedt, R.A.; McDonald, R.

    2010-01-01

    Sea lamprey invaded the Great Lakes in the early 20th century and caused an abrupt decline in the population densities of several native fish species. The integrated management of this invasive species is composed of chemical (lampricide) applications, low-head barrier dams, adult trapping and sterile male release. Recently, there has been an increased emphasis on the development of control methods alternative to lampricide applications. We propose as an alternative-control method the use of chemosensory cues as repellents for sea lamprey population management. Based on the available evidence at this time, we suggest that injury-released chemical alarm cues show promise as repellents for sea lamprey and further research should be directed at determining whether sea lamprey show an avoidance response to these types of chemosensory cues. From a management perspective, these chemosensory cues could be used to restrict sea lamprey access to spawning grounds. Repellents could also be used together with attractants like sex pheromones to manipulate sea lamprey behavior, similar to the "push-pull" strategies utilized with insect pests. ?? 2010 Elsevier B.V.

  15. Lampreys as Diverse Model Organisms in the Genomics Era.

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    McCauley, David W; Docker, Margaret F; Whyard, Steve; Li, Weiming

    2015-11-01

    Lampreys, one of the two surviving groups of ancient vertebrates, have become important models for study in diverse fields of biology. Lampreys (of which there are approximately 40 species) are being studied, for example, (a) to control pest sea lamprey in the North American Great Lakes and to restore declining populations of native species elsewhere; (b) in biomedical research, focusing particularly on the regenerative capability of lampreys; and (c) by developmental biologists studying the evolution of key vertebrate characters. Although a lack of genetic resources has hindered research on the mechanisms regulating many aspects of lamprey life history and development, formerly intractable questions are now amenable to investigation following the recent publication of the sea lamprey genome. Here, we provide an overview of the ways in which genomic tools are currently being deployed to tackle diverse research questions and suggest several areas that may benefit from the availability of the sea lamprey genome.

  16. Development of sea lamprey (Petromyzon marinus) larvicides

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    Howell, John H.; Lech, John J.; Allen, John L.

    1980-01-01

    Larvicides are used to control sea lamprey (Petromyzon marinus) in the Great Lakes. These larvicides are useful because they are more toxic to sea lamprey than fish species found in the same habitat. The lampricides come from two classes of chemical compounds: (1) halonitrophenols, and (2) halonitrosalicylanilides. Selectivity of the larvicides appears to be based on the differences in the ability of sea lamprey larvae and fishes to detoxify and/or excrete the chemicals. Glucuronide conjugation is an important mechanism for detoxification of these larvicides by fish, and selectivity of larvicides may be due to differences in glucuronyl transferase activity between lamprey and fishes. If more detailed information were available on uptake, metabolism, excretion, and the biochemistry and physiology of lamprey as compared to fishes, it might be possible to design chemicals that would be more selective than those now in use.

  17. Behavioral responses of Pacific lamprey to alarm cues

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    Porter, Laurie L.; Hayes, Michael C.; Jackson, Aaron D.; Burke, Brian J.; Moser, Mary L.; Wagner, R. Steven

    2017-01-01

    Pacific lamprey (Entosphenus tridentatus), an anadromous ectoparasite, faces several challenges during adult migration to spawning grounds. Developing methods to address these challenges is critical to the success of ongoing conservation efforts. The challenges are diverse, and include anthropogenic alterations to the ecosystem resulting in loss of habitat, impassable barriers such as dams, climate change impacts, and altered predator fields. We conducted a behavioral study to understand how adult migrating Pacific lamprey respond to potential alarm cues: White Sturgeon (Acipenser transmontanus), human saliva, decayed Pacific lamprey, and river otter (Lontra canadensis). Research has shown that some species of lamprey can be guided to a location using odors and similar cues may be useful as a management tool for Pacific lamprey. Experiments were conducted over 2 nights and measured the number of entries (count) and duration of time spent (occupancy) by adult lamprey in each arm of a two-choice maze. During the first night, no odor was added to test for selection bias between arms. During the second night odor was added to one arm of the maze. Contrary to expectations, lamprey were significantly attracted to the river otter odor in both count and occupancy. No significant differences were found in the response of lamprey to the other three odors. Results from this study indicate that Pacific lamprey do respond to some odors; however, additional tests are necessary to better identify the types of odors and concentrations that elicit a repeatable response.

  18. Tradeoff between assessment and control of aquatic invasive species: A case study of sea lamprey management in the St. Marys River

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    Robinson, Jason M.; Wilberg, Michael J.; Adams, Jean V.; Jones, Michael L.

    2016-01-01

    Allocating resources between the gathering of information to guide management actions and implementing those actions presents an inherent tradeoff. This tradeoff is evident for control of the Sea Lamprey Petromyzon marinus in the St. Marys River, connecting Lakes Huron and Superior and a major source of parasitic Sea Lampreys to Lake Huron and northern Lake Michigan. Larval Sea Lampreys in the St. Marys River are controlled through the application of Bayluscide, which is applied to areas of high larval density. Bayluscide applications are guided with an annual deepwater electrofishing survey to estimate larval Sea Lamprey density at relatively fine spatial scales. We took a resampling approach to describe the effect of sampling intensity on the success of the larval Sea Lamprey management program and explicitly incorporated the economic tradeoff between assessment and control efforts to maximize numbers of larvae killed in the St. Marys River. When no tradeoff between assessment and control was incorporated, increasing assessment always led to more larvae killed for the same treatment budget. When the tradeoff was incorporated, the sampling intensity that maximized the number of larvae killed depended on the overall budget available. Increased sampling intensities maximized effectiveness under medium to large budgets (US \\$0.4 to \\$2.0 million), and intermediate sampling intensities maximized effectiveness under low budgets. Sea Lamprey control actions based on assessment information outperformed those that were implemented with no assessment under all budget scenarios.

  19. Vulnerability of larval lamprey to Columbia River hydropower system operations—effects of dewatering on larval lamprey movements and survival

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    Liedtke, Theresa L.; Weiland, Lisa K.; Mesa, Matthew G.

    2015-08-27

    Numbers of adult and juvenile Pacific lamprey ( Entosphenus tridentatus ) in the upper Columbia River Basin of the interior Pacific Northwest have decreased from historical levels (Close and others, 2002), raising concerns f rom State and Federal agencies and Tribal entities. In 1994, the U.S. Fish and Wildlife Service designated Pacific lamprey as a Category 2 candidate species and in 2003, the species was petitioned for listing under the Endangered Species Act. Listing consideration and potential recovery planning are significantly hindered by a lack of information on the basic biology and ecology of lampreys, including limiting factors. To date (2015), several factors that may limit lamprey production require study, including dam passage issues, contaminants, and effects on habitat.

  20. Evaluating harvest-based control of invasive fish with telemetry: Performance of sea lamprey traps in the Great Lakes

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    Holbrook, Christopher; Bergstedt, Roger A.; Barber, Jessica M.; Bravener, Gale A; Jones, Michael L.; Krueger, Charles C.

    2016-01-01

    Physical removal (e.g., harvest via traps or nets) of mature individuals may be a cost-effective or socially acceptable alternative to chemical control strategies for invasive species, but requires knowledge of the spatial distribution of a population over time. We used acoustic telemetry to determine the current and possible future role of traps to control and assess invasive sea lampreys, Petromyzon marinus, in the St. Marys River, the connecting channel between Lake Superior and Lake Huron. Exploitation rates (i.e., fractions of an adult sea lamprey population removed by traps) at two upstream locations were compared among three years and two points of entry to the system. Telemetry receivers throughout the drainage allowed trap performance (exploitation rate) to be partitioned into two components: proportion of migrating sea lampreys that visited trap sites (availability) and proportion of available sea lampreys that were caught by traps (local trap efficiency). Estimated exploitation rates were well below those needed to provide population control in the absence of lampricides and were limited by availability and local trap efficiency. Local trap efficiency estimates for acoustic-tagged sea lampreys were lower than analogous estimates regularly obtained using traditional mark–recapture methods, suggesting that abundance had been previously underestimated. Results suggested major changes would be required to substantially increase catch, including improvements to existing traps, installation of new traps, or other modifications to attract and retain more sea lampreys. This case study also shows how bias associated with telemetry tags can be estimated and incorporated in models to improve inferences about parameters that are directly relevant to fishery management.

  1. Genome-wide analysis of the ATP-binding cassette (ABC) transporter gene family in sea lamprey and Japanese lamprey.

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    Ren, Jianfeng; Chung-Davidson, Yu-Wen; Yeh, Chu-Yin; Scott, Camille; Brown, Titus; Li, Weiming

    2015-06-06

    Lampreys are extant representatives of the jawless vertebrate lineage that diverged from jawed vertebrates around 500 million years ago. Lamprey genomes contain information crucial for understanding the evolution of gene families in vertebrates. The ATP-binding cassette (ABC) gene family is found from prokaryotes to eukaryotes. The recent availability of two lamprey draft genomes from sea lamprey Petromyzon marinus and Japanese lamprey Lethenteron japonicum presents an opportunity to infer early evolutionary events of ABC genes in vertebrates. We conducted a genome-wide survey of the ABC gene family in two lamprey draft genomes. A total of 37 ABC transporters were identified and classified into seven subfamilies; namely seven ABCA genes, 10 ABCB genes, 10 ABCC genes, three ABCD genes, one ABCE gene, three ABCF genes, and three ABCG genes. The ABCA subfamily has expanded from three genes in sea squirts, seven and nine in lampreys and zebrafish, to 13 and 16 in human and mouse. Conversely, the multiple copies of ABCB1-, ABCG1-, and ABCG2-like genes found in sea squirts have contracted in the other species examined. ABCB2 and ABCB3 seem to be new additions in gnathostomes (not in sea squirts or lampreys), which coincides with the emergence of the gnathostome-specific adaptive immune system. All the genes in the ABCD, ABCE and ABCF subfamilies were conserved and had undergone limited duplication and loss events. In the sea lamprey transcriptomes, the ABCE and ABCF gene subfamilies were ubiquitously and highly expressed in all tissues while the members in other gene subfamilies were differentially expressed. Thirteen more lamprey ABC transporter genes were identified in this study compared with a previous study. By concatenating the same gene sequences from the two lampreys, more full length sequences were obtained, which significantly improved both the assignment of gene names and the phylogenetic trees compared with a previous analysis using partial sequences. The ABC

  2. Behavior and potential threats to survival of migrating lamprey ammocoetes and macrophthalmia

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Mary L.; Jackson, Aaron D.; Lucas, Martyn C.; Mueller, Robert P.

    2015-03-01

    Upon metamorphosis, anadromous juvenile lamprey (macrophthalmia) exhibit distinct migration behaviors that take them from larval rearing habitats in streams to the open ocean. While poorly studied, lamprey larvae (ammocoetes) also engage in downstream movement to some degree. Like migrating salmon smolts, lamprey macrophthalmia undergo behavioral changes associated with a highly synchronized metamorphosis. Unlike salmon smolts, the timing of juvenile migration in lamprey is protracted and poorly documented. Lamprey macrophthalmia and ammocoetes are not strong swimmers, attaining maximum individual speeds of less than 1 m s-1, and sustained speeds of less than 0.5 m s-1. They are chiefly nocturnal and distribute throughout the water column, but appear to concentrate near the bottom in the thalweg of deep rivers. At dams and irrigation diversions, macrophthalmia can become impinged on screens or entrained in irrigation canals, suffer increased predation, and experience physical injury that may result in direct or delayed mortality. The very structures designed to protect migrating juvenile salmonids can be harmful to juvenile lamprey. Yet at turbine intakes and spillways, lampreys, which have no swim bladder, can withstand changes in pressure and shear stress large enough to injure or kill most teleosts. Lamprey populations are in decline in many parts of the world, with some species designated as species of concern for conservation that merit legally mandated protections. Hence, provisions for safe passage of juvenile lamprey are being considered at dams and water diversions in North America and Europe.

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

    Science.gov (United States)

    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.

  4. Ultra-performance liquid chromatography tandem mass spectrometry for simultaneous determination of natural steroid hormones in sea lamprey (Petromyzon marinus) plasma and tissues.

    Science.gov (United States)

    Wang, Huiyong; Bussy, Ugo; Chung-Davidson, Yu-Wen; Li, Weiming

    2016-01-15

    This study aims to provide a rapid, sensitive and precise UPLC-MS/MS method for target steroid quantitation in biological matrices. We developed and validated an UPLC-MS/MS method to simultaneously determine 16 steroids in plasma and tissue samples. Ionization sources of Electrospray Ionization (ESI) and Atmospheric Pressure Chemical Ionization (APCI) were compared in this study by testing their spectrometry performances at the same chromatographic conditions, and the ESI source was found up to five times more sensitive than the APCI. Different sample preparation techniques were investigated for an optimal extraction of steroids from the biological matrices. The developed method exhibited excellent linearity for all analytes with regression coefficients higher than 0.99 in broad concentration ranges. The limit of detection (LOD) was from 0.003 to 0.1ng/mL. The method was validated according to FDA guidance and applied to determine steroids in sea lamprey plasma and tissues (fat and testes) by the developed method. Copyright © 2015. Published by Elsevier B.V.

  5. Sea lamprey (Petromyzon marinus) parasite-host interactions in the Great Lakes

    Science.gov (United States)

    Bence, James R.; Bergstedt, Roger A.; Christie, Gavin C.; Cochran, Phillip A.; Ebener, Mark P.; Koonce, Joseph F.; Rutter, Michael A.; Swink, William D.

    2003-01-01

    Prediction of how host mortality responds to efforts to control sea lampreys (Petromyzon marinus) is central to the integrated management strategy for sea lamprey (IMSL) in the Great Lakes. A parasite-host submodel is used as part of this strategy, and this includes a type-2 multi-species functional response, a developmental response, but no numerical response. General patterns of host species and size selection are consistent with the model assumptions, but some observations appear to diverge. For example, some patterns in sea lamprey marking on hosts suggest increases in selectivity for less preferred hosts and lower host survival when preferred hosts are scarce. Nevertheless, many of the IMSL assumptions may be adequate under conditions targeted by fish community objectives. Of great concern is the possibility that the survival of young parasites (parasitic-phase sea lampreys) varies substantially among lakes or over time. Joint analysis of abundance estimates for parasites being produced in streams and returning spawners could address this. Data on sea lamprey marks is a critical source of information on sea lamprey activity and potential effects. Theory connecting observed marks to sea lamprey feeding activity and host mortality is reviewed. Uncertainties regarding healing and attachment times, the probability of hosts surviving attacks, and problems in consistent classification of marks have led to widely divergent estimates of damages caused by sea lamprey. Laboratory and field studies are recommended to provide a firmer linkage between host blood loss, host mortality, and observed marks on surviving hosts, so as to improve estimates of damage.

  6. Status report of the Pacific lamprey (Lampetra tridentata) in the Columbia River Basin

    International Nuclear Information System (INIS)

    Close, D.A.; Fitzpatrick, M.; Li, H.; James, G.

    1995-07-01

    The widespread decline of Pacific lamprey (Lampetra tridentata) in the Pacific Northwest, especially in the Columbia River system has led to concerns and questions from a number of regional agencies, Native American tribes, and the public. To address these concerns, new research efforts must focus on specific problems associated with this understudied species. The preservation and restoration of this species is critical for a number of reasons, including its importance to the tribes and its importance as an indicator of ecosystem health. Historically lamprey have been labeled a pest species due to the problems associated with the exotic sea lamprey, (Petromyzon marinus), invading the Great Lakes

  7. Status Report of the Pacific Lamprey (Lampetra Trzdentata) in the Columbia River Basin.

    Energy Technology Data Exchange (ETDEWEB)

    Close, David A.; Parker, Blaine; James, gary

    1995-07-01

    The widespread decline of Pacific lamprey (Lampetra tridentata) in the Pacific Northwest, especially in the Columbia River system has led to concerns and questions from a number of regional agencies, Native American tribes, and the public. To address these concerns, new research efforts must focus on specific problems associated with this understudied species. The preservation and restoration of this species is critical for a number of reasons, including its importance to the tribes and its importance as an indicator of ecosystem health. Historically lamprey have been labeled a pest species due to the problems associated with the exotic sea lamprey, (Petromyzon marinus), invading the Great Lakes.

  8. Influence of body size, metabolic rate and life history stage on the uptake and excretion of the lampricide 3-trifluoromethyl-4-nitrophenol (TFM) by invasive sea lampreys (Petromyzon marinus).

    Science.gov (United States)

    Tessier, Laura R; Long, Tristan A F; Wilkie, Michael P

    2018-01-01

    Invasive sea lamprey (Petromyzon marinus) are controlled in the Great Lakes using the lampricide 3-trifluoromethyl-4-nitrophenol (TFM), which is applied to streams infested with larval lamprey. However, lamprey that survive treatments (residuals) remain a challenge because they may subsequently undergo metamorphosis into parasitic juvenile animals that migrate downstream to the Great Lakes, where they feed on important sport and commercial fishes. The goal of this study was to determine if body size and life stage could potentially influence sea lamprey tolerance to TFM by influencing patterns of TFM uptake and elimination. Because mass specific rates of oxygen consumption (M˙O 2 ) are lower in larger compared to smaller lamprey, we predicted that TFM uptake would be negatively correlated to body size, suggesting that large larvae would be more tolerant to TFM exposure. Accordingly, TFM uptake and M˙O 2 were measured in larvae ranging in size from 0.2-4.2g using radio-labelled TFM ( 14 C-TFM) and static respirometry. Both were inversely proportional to wet mass (M), and could be described usingthe allometric power relationship: Y=aM b , in which M˙O 2 =1.86M 0.53 and TFM Uptake=7.24M 0.34 . We also predicted that body size would extend to rates of TFM elimination, which was measured following the administration of 14 C-TFM (via intraperitoneal injection). However, there were no differences in the half-lives of elimination of TFM (T 1/2 -TFM). There were also no differences in M˙O 2 or TFM uptake amongst size-matched larval, metamorphosing (stages 6-7), or post-metamorphic (juvenile) sea lamprey. However, the T 1/2 -TFM was significantly lower in larval than post-metamorphic lamprey (juvenile), indicating the larval lamprey cleared TFM more efficiently than juvenile lamprey. We conclude that larger larval sea lamprey are more likely to survive TFM treatments suggesting that body size might be an important variable to consider when treating streams with TFM to

  9. Sequencing of the sea lamprey (Petromyzon marinus) genome provides insights into vertebrate evolution

    Science.gov (United States)

    Smith, Jeramiah J; Kuraku, Shigehiro; Holt, Carson; Sauka-Spengler, Tatjana; Jiang, Ning; Campbell, Michael S; Yandell, Mark D; Manousaki, Tereza; Meyer, Axel; Bloom, Ona E; Morgan, Jennifer R; Buxbaum, Joseph D; Sachidanandam, Ravi; Sims, Carrie; Garruss, Alexander S; Cook, Malcolm; Krumlauf, Robb; Wiedemann, Leanne M; Sower, Stacia A; Decatur, Wayne A; Hall, Jeffrey A; Amemiya, Chris T; Saha, Nil R; Buckley, Katherine M; Rast, Jonathan P; Das, Sabyasachi; Hirano, Masayuki; McCurley, Nathanael; Guo, Peng; Rohner, Nicolas; Tabin, Clifford J; Piccinelli, Paul; Elgar, Greg; Ruffier, Magali; Aken, Bronwen L; Searle, Stephen MJ; Muffato, Matthieu; Pignatelli, Miguel; Herrero, Javier; Jones, Matthew; Brown, C Titus; Chung-Davidson, Yu-Wen; Nanlohy, Kaben G; Libants, Scot V; Yeh, Chu-Yin; McCauley, David W; Langeland, James A; Pancer, Zeev; Fritzsch, Bernd; de Jong, Pieter J; Zhu, Baoli; Fulton, Lucinda L; Theising, Brenda; Flicek, Paul; Bronner, Marianne E; Warren, Wesley C; Clifton, Sandra W; Wilson, Richard K; Li, Weiming

    2013-01-01

    Lampreys are representatives of an ancient vertebrate lineage that diverged from our own ~500 million years ago. By virtue of this deeply shared ancestry, the sea lamprey (P. marinus) genome is uniquely poised to provide insight into the ancestry of vertebrate genomes and the underlying principles of vertebrate biology. Here, we present the first lamprey whole-genome sequence and assembly. We note challenges faced owing to its high content of repetitive elements and GC bases, as well as the absence of broad-scale sequence information from closely related species. Analyses of the assembly indicate that two whole-genome duplications likely occurred before the divergence of ancestral lamprey and gnathostome lineages. Moreover, the results help define key evolutionary events within vertebrate lineages, including the origin of myelin-associated proteins and the development of appendages. The lamprey genome provides an important resource for reconstructing vertebrate origins and the evolutionary events that have shaped the genomes of extant organisms. PMID:23435085

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

    Science.gov (United States)

    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.

  11. Lateral and vertical distribution of downstream migrating juvenile sea lamprey

    Science.gov (United States)

    Sotola, V. Alex; Miehls, Scott M.; Simard, Lee G.; Marsden, J. Ellen

    2018-01-01

    Sea lamprey is considered an invasive and nuisance species in the Laurentian Great Lakes, Lake Champlain, and the Finger Lakes of New York and is a major focus of control efforts. Currently, management practices focus on limiting the area of infestation using barriers to block migratory adults, and lampricides to kill ammocoetes in infested tributaries. No control efforts currently target the downstream-migrating post-metamorphic life stage which could provide another management opportunity. In order to apply control methods to this life stage, a better understanding of their downstream movement patterns is needed. To quantify spatial distribution of downstream migrants, we deployed fyke and drift nets laterally and vertically across the stream channel in two tributaries of Lake Champlain. Sea lamprey was not randomly distributed across the stream width and lateral distribution showed a significant association with discharge. Results indicated that juvenile sea lamprey is most likely to be present in the thalweg and at midwater depths of the stream channel. Further, a majority of the catch occurred during high flow events, suggesting an increase in downstream movement activity when water levels are higher than base flow. Discharge and flow are strong predictors of the distribution of out-migrating sea lamprey, thus managers will need to either target capture efforts in high discharge areas of streams or develop means to guide sea lamprey away from these areas.

  12. PCB concentrations and activity of sea lamprey Petromyzon marinus vary by sex

    Science.gov (United States)

    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.

  13. Boll weevil eradication: a model for sea lamprey control?

    Science.gov (United States)

    Smith, James W.; Swink, William D.

    2003-01-01

    Invasions of boll weevil (Anthonomus grandis) into the United States and sea lamprey (Petromyzon marinus) into the Great Lakes were similar in many ways. Important species (American cotton, Gossypium hirsutum, and lake trout, Salvelinus namaycush) and the industries they supported were negatively affected. Initial control efforts were unsuccessful until pesticides and application technologies were developed. For boll weevils, controls relying on pesticides evolved into an integrated program that included recommended farming practices and poisoned baits. However, the discovery of a boll weevil sex pheromone in 1964 allowed adoption of an ongoing program of eradication. Despite opposition over concept and cost, insecticides, pheromone traps, poisoned baits, and approved farming practices were used to eradicate boll weevils from Virginia, North Carolina, South Carolina, Georgia, Florida, and Alabama by 1999. Using the working back approach along the path of the original invasion, eradication was nearly completed by 2002 in Mississippi and eradication programs were underway in Arkansas, Tennessee, Oklahoma, Louisiana, and parts of Texas. Insecticide use for cotton production decreased 50 to 90%, and cotton yields and farm income increased an average of 78 kg/ha and $190 U.S./ha in areas where boll weevils were eradicated. For sea lampreys, integrated management uses lampricides, barriers to migration, trapping, and release of sterilized males. Although sea lamprey eradication is not currently feasible, recent research on larval and sex pheromones might provide the tools to make it possible. A successful eradication program for sea lampreys starting in Lake Superior and expanding to the lower Great Lakes would ultimately provide huge ecological and economic benefits by eliminating lampricide applications, removing barriers that block teleost fishes, and facilitating the recovery of lake trout. Should the opportunity arise, the concept of sea lamprey eradication should

  14. Hsp90 and hepatobiliary transformation during sea lamprey metamorphosis.

    Science.gov (United States)

    Chung-Davidson, Yu-Wen; Yeh, Chu-Yin; Bussy, Ugo; Li, Ke; Davidson, Peter J; Nanlohy, Kaben G; Brown, C Titus; Whyard, Steven; Li, Weiming

    2015-12-01

    Biliary atresia (BA) is a human infant disease with inflammatory fibrous obstructions in the bile ducts and 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. Therefore, sea lamprey liver metamorphosis may serve as an etiological model for human BA and provide pivotal information for hepatobiliary transformation and possible therapeutics. We hypothesized that liver metamorphosis in sea lamprey is due to transcriptional reprogramming that dictates cellular remodeling during metamorphosis. We determined global gene expressions in liver at several metamorphic landmark stages by integrating mRNA-Seq and gene ontology analyses, and validated the results with real-time quantitative PCR, histological and immunohistochemical staining. These analyses revealed that gene expressions of protein folding chaperones, membrane transporters and extracellular matrices were altered and shifted during liver metamorphosis. HSP90, important in protein folding and invertebrate metamorphosis, was identified as a candidate key factor during liver metamorphosis in sea lamprey. Blocking HSP90 with geldanamycin facilitated liver metamorphosis and decreased the gene expressions of the rate limiting enzyme for cholesterol biosynthesis, HMGCoA reductase (hmgcr), and bile acid biosynthesis, cyp7a1. Injection of hsp90 siRNA for 4 days altered gene expressions of met, hmgcr, cyp27a1, and slc10a1. Bile acid concentrations were increased while bile duct and gall bladder degeneration was facilitated and synchronized after hsp90 siRNA injection. HSP90 appears to play crucial roles in hepatobiliary transformation during sea lamprey metamorphosis. Sea lamprey is a useful animal model to study postembryonic development and mechanisms for hsp90-induced hepatobiliary transformation.

  15. Factors influencing capture of invasive sea lamprey in traps baited with a synthesized sex pheromone component

    Science.gov (United States)

    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 (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.

  16. Electrical guidance efficiency of downstream-migrating juvenile Sea Lamprey decreases with increasing water velocity

    Science.gov (United States)

    Miehls, Scott M.; Johnson, Nicholas; Haro, Alexander

    2017-01-01

    We tested the efficacy of a vertically oriented field of pulsed direct current (VEPDC) created by an array of vertical electrodes for guiding downstream-moving juvenile Sea Lampreys Petromyzon marinus to a bypass channel in an artificial flume at water velocities of 10–50 cm/s. Sea Lampreys were more likely to be captured in the bypass channel than in other sections of the flume regardless of electric field status (on or off) or water velocity. Additionally, Sea Lampreys were more likely to be captured in the bypass channel when the VEPDC was active; however, an interaction between the effects of VEPDC and water velocity was observed, as the likelihood of capture decreased with increases in water velocity. The distribution of Sea Lampreys shifted from right to left across the width of the flume toward the bypass channel when the VEPDC was active at water velocities less than 25 cm/s. The VEPDC appeared to have no effect on Sea Lamprey distribution in the flume at water velocities greater than 25 cm/s. We also conducted separate tests to determine the threshold at which Sea Lampreys would become paralyzed. Individuals were paralyzed at a mean power density of 37.0 µW/cm3. Future research should investigate the ability of juvenile Sea Lampreys to detect electric fields and their specific behavioral responses to electric field characteristics so as to optimize the use of this technology as a nonphysical guidance tool across variable water velocities.

  17. Large wood and in-stream habitat for juvenile coho salmon and larval lampreys in a Pacific Northwest stream

    Science.gov (United States)

    Gonzalez, Rosalinda; Dunham, Jason B.; Lightcap, Scott W.; McEnroe, Jeffery R.

    2017-01-01

    The influences of large wood on Pacific salmon are well-studied, but studies of nonsalmonid species such as lampreys are uncommon. To address this need, we evaluated the potential effects of large wood on larval lampreys (Pacific Lamprey, Entosphenus tridentatus; and potentially Western Brook Lamprey Lampetra richardsoni), as well as juvenile Coho Salmon Oncorhynchus kisutch, in a small coastal Oregon stream. Our objectives were to 1) identify in-stream habitat characteristics associated with the presence of larval lampreys and abundance of juvenile Coho Salmon; and 2) evaluate how these characteristics were associated with in-stream wood. To address habitat use, we quantified presence of larval lampreys in 92 pools and abundance of juvenile Coho Salmon in 44 pools during summer low flows. We focused on a study reach where large wood was introduced into the stream between 2008 and 2009. Results indicated that presence of larval lampreys was significantly associated with availability of fine sediment and deeper substrate. The abundance of juvenile Coho Salmon (fish/pool) was strongly associated with pool surface area and to a weaker extent with the proportion of cobble and boulder substrates in pools. Pools with wood, regardless of whether they were formed by wood, had significantly greater coverage of fine sediment, deeper substrate, and greater pool surface area. Taken together, these results suggest that in-stream wood can provide habitat associated with presence of larval lampreys and greater abundance of juvenile Coho Salmon.

  18. Seasonal patterns in growth, blood consumption, and effects on hosts by parasitic-phase sea lampreys in the Great Lakes: an individual-based model approach

    Science.gov (United States)

    Madenjian, Charles P.; Cochran, Philip A.; Bergstedt, Roger A.

    2003-01-01

    An individual-based model (IBM) was developed for sea lamprey (Petromyzon marinus) populations in the Laurentian Great Lakes. The IBM was then calibrated to observed growth, by season, for sea lampreys in northern Lake Huron under two different water temperature regimes: a regime experienced by Seneca-strain lake trout (Salvelinus namaycush) and a regime experienced by Marquettestrain lake trout. Modeling results indicated that seasonal blood consumption under the Seneca regime was very similar to that under the Marquette regime. Simulated mortality of lake trout directly due to blood removal by sea lampreys occurred at nearly twice the rate during August and September under the Marquette regime than under the Seneca regime. However, cumulative sea lamprey-induced mortality on lake trout over the entire duration of the sea lamprey's parasitic phase was only 7% higher for the Marquette regime compared with the Seneca regime. Thus, these modeling results indicated that the strain composition of the host (lake trout) population was not important in determining total number of lake trout deaths or total blood consumption attributable to the sea lamprey population, given the sea lamprey growth pattern. Regardless of water temperature regime, both blood consumption rate by sea lampreys and rate of sea lamprey-induced mortality on lake trout peaked in late October. Elevated blood consumption in late October appeared to be unrelated to changes in water temperature. The IBM approach should prove useful in optimizing control of sea lampreys in the Laurentian Great Lakes.

  19. 76 FR 43698 - Lake Champlain Sea Lamprey Control Alternatives Workgroup

    Science.gov (United States)

    2011-07-21

    ... implementation of sea lamprey control techniques alternative to lampricide that are technically feasible, cost... provide advice regarding the implementation of sea lamprey control methods alternative to lampricides, to...

  20. 76 FR 12129 - Lake Champlain Sea Lamprey Control Alternatives Workgroup

    Science.gov (United States)

    2011-03-04

    ... implementation of sea lamprey control techniques alternative to lampricide that are technically feasible, cost... regarding the implementation of sea lamprey control methods alternative to lampricides, to recommend...

  1. 11-Deoxycortisol is a corticosteroid hormone in the lamprey

    Science.gov (United States)

    Close, D.A.; Yun, S.-S.; McCormick, S.D.; Wildbill, A.J.; Li, W.

    2010-01-01

    Corticosteroid hormones are critical for controlling metabolism, hydromineral balance, and the stress response in vertebrates. Although corticosteroid hormones have been well characterized in most vertebrate groups, the identity of the earliest vertebrate corticosteroid hormone has remained elusive. Here we provide evidence that 11-deoxycortisol is the corticosteroid hormone in the lamprey, a member of the agnathans that evolved more than 500 million years ago. We used RIA, HPLC, and mass spectrometry analysis to determine that 11-deoxycortisol is the active corticosteroid present in lamprey plasma. We also characterized an 11-deoxycortisol receptor extracted from sea lamprey gill cytosol. The receptor was highly specific for 11-deoxycortisol and exhibited corticosteroid binding characteristics, including DNA binding. Furthermore, we observed that 11-deoxycortisol was regulated by the hypothalamus-pituitary axis and responded to acute stress. 11-Deoxycortisol implants reduced sex steroid concentrations and upregulated gill Na+, K+-ATPase, an enzyme critical for ion balance. We show here that 11-deoxycortisol functioned as both a glucocorticoid and a mineralocorticoid in the lamprey. Our findings indicate that a complex and highly specific corticosteroid signaling pathway evolved at least 500 million years ago with the arrival of the earliest vertebrate.

  2. Deep ancestry of programmed genome rearrangement in lampreys.

    Science.gov (United States)

    Timoshevskiy, Vladimir A; Lampman, Ralph T; Hess, Jon E; Porter, Laurie L; Smith, Jeramiah J

    2017-09-01

    In most multicellular organisms, the structure and content of the genome is rigorously maintained over the course of development. However some species have evolved genome biologies that permit, or require, developmentally regulated changes in the physical structure and content of the genome (programmed genome rearrangement: PGR). Relatively few vertebrates are known to undergo PGR, although all agnathans surveyed to date (several hagfish and one lamprey: Petromyzon marinus) show evidence of large scale PGR. To further resolve the ancestry of PGR within vertebrates, we developed probes that allow simultaneous tracking of nearly all sequences eliminated by PGR in P. marinus and a second lamprey species (Entosphenus tridentatus). These comparative analyses reveal conserved subcellular structures (lagging chromatin and micronuclei) associated with PGR and provide the first comparative embryological evidence in support of the idea that PGR represents an ancient and evolutionarily stable strategy for regulating inherent developmental/genetic conflicts between germline and soma. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Upstream migration of Pacific lampreys in the John Day River, Oregon: Behavior, timing, and habitat use

    Science.gov (United States)

    Robinson, T. Craig; Bayer, J.M.

    2005-01-01

    Adult Pacific lamprey migration and habitat preferences for over-winter holding and spawning, and larval rearing in tributaries to the Columbia River are not well understood. The John Day River is one such tributary where larval and adult stages of this species have been documented, and its free-flowing character provided the opportunity to study migration of Pacific lampreys unimpeded by passage constraints. Forty-two adult Pacific lampreys were captured in the John Day River near its mouth during their upstream migration. Pacific lampreys were surgically implanted with radio transmitters and released onsite, and tracked by fixed-site, aerial, and terrestrial telemetry methods for nearly one year. Adults moved upstream exclusively at night, with a mean rate of 11.1 ?? 6.3 km/day. They halted upstream migration by September, and held a single position for approximately six months in the lateral margins of riffles and glides, using boulders for cover. More than half of Pacific lampreys resumed migration in March before ending movement in early May. Pacific lampreys that resumed migration in spring completed a median of 87% of their upstream migration before over-winter holding. Upon completing migration. Pacific lampreys briefly held position before beginning downstream movement at the end of May. Though not directly observed, halting migration and movement downstream were likely the result of spawning and death. Gains in adult Pacific lamprey passage through the Columbia River hydrosystem and tributaries may be made by improvements that would expedite migration during spring and summer and increase the quantity and variety of cover and refuge opportunities. ?? 2005 by the Northwest Scientific Association. All rights reserved.

  4. RNA Interference Technology to Control Pest Sea Lampreys - A Proof-of-Concept

    Science.gov (United States)

    Heath, George; Childs, Darcy; Docker, Margaret F.; McCauley, David W.; Whyard, Steven

    2014-01-01

    The parasitic sea lamprey (Petromyzon marinus) has caused extensive losses to commercial fish stocks of the upper Great Lakes of North America. Methods of controlling the sea lamprey include trapping, barriers to prevent migration, and use of a chemical lampricide (3-trifluoromethyl-4-nitrophenol) to kill the filter-feeding larvae. Concerns about the non-specificity of these methods have prompted continued development of species-specific methods to control lampreys outside their native range. In this study, we considered the utility of RNA interference to develop a sea lamprey-specific lampricide. Injection of six different short interfering, double-stranded RNAs (siRNAs) into lamprey embryos first confirmed that the siRNAs could reduce the targeted transcript levels by more than 50%. Two size classes of lamprey larvae were then fed the siRNAs complexed with liposomes, and three of the siRNAs (targeting elongation factor 1α, calmodulin, and α-actinin) reduced transcript levels 2.5, 3.6, and 5.0–fold, respectively, within the lamprey midsections. This is not only the first demonstration of RNAi in lampreys, but it is also the first example of delivery of siRNAs to a non-mammalian vertebrate through feeding formulations. One of the siRNA treatments also caused increased mortality of the larvae following a single feeding of siRNAs, which suggests that prolonged or multiple feedings of siRNAs could be used to kill filter-feeding larvae within streams, following development of a slow-release formulation. The genes targeted in this study are highly conserved across many species, and only serve as a proof-of-concept demonstration that siRNAs can be used in lampreys. Given that RNA interference is a sequence-specific phenomenon, it should be possible to design siRNAs that selectively target gene sequences that are unique to sea lampreys, and thus develop a technology to control these pests without adversely affecting non-target species. PMID:24505485

  5. RNA interference technology to control pest sea lampreys--a proof-of-concept.

    Directory of Open Access Journals (Sweden)

    George Heath

    Full Text Available The parasitic sea lamprey (Petromyzon marinus has caused extensive losses to commercial fish stocks of the upper Great Lakes of North America. Methods of controlling the sea lamprey include trapping, barriers to prevent migration, and use of a chemical lampricide (3-trifluoromethyl-4-nitrophenol to kill the filter-feeding larvae. Concerns about the non-specificity of these methods have prompted continued development of species-specific methods to control lampreys outside their native range. In this study, we considered the utility of RNA interference to develop a sea lamprey-specific lampricide. Injection of six different short interfering, double-stranded RNAs (siRNAs into lamprey embryos first confirmed that the siRNAs could reduce the targeted transcript levels by more than 50%. Two size classes of lamprey larvae were then fed the siRNAs complexed with liposomes, and three of the siRNAs (targeting elongation factor 1α, calmodulin, and α-actinin reduced transcript levels 2.5, 3.6, and 5.0-fold, respectively, within the lamprey midsections. This is not only the first demonstration of RNAi in lampreys, but it is also the first example of delivery of siRNAs to a non-mammalian vertebrate through feeding formulations. One of the siRNA treatments also caused increased mortality of the larvae following a single feeding of siRNAs, which suggests that prolonged or multiple feedings of siRNAs could be used to kill filter-feeding larvae within streams, following development of a slow-release formulation. The genes targeted in this study are highly conserved across many species, and only serve as a proof-of-concept demonstration that siRNAs can be used in lampreys. Given that RNA interference is a sequence-specific phenomenon, it should be possible to design siRNAs that selectively target gene sequences that are unique to sea lampreys, and thus develop a technology to control these pests without adversely affecting non-target species.

  6. RNA interference technology to control pest sea lampreys--a proof-of-concept.

    Science.gov (United States)

    Heath, George; Childs, Darcy; Docker, Margaret F; McCauley, David W; Whyard, Steven

    2014-01-01

    The parasitic sea lamprey (Petromyzon marinus) has caused extensive losses to commercial fish stocks of the upper Great Lakes of North America. Methods of controlling the sea lamprey include trapping, barriers to prevent migration, and use of a chemical lampricide (3-trifluoromethyl-4-nitrophenol) to kill the filter-feeding larvae. Concerns about the non-specificity of these methods have prompted continued development of species-specific methods to control lampreys outside their native range. In this study, we considered the utility of RNA interference to develop a sea lamprey-specific lampricide. Injection of six different short interfering, double-stranded RNAs (siRNAs) into lamprey embryos first confirmed that the siRNAs could reduce the targeted transcript levels by more than 50%. Two size classes of lamprey larvae were then fed the siRNAs complexed with liposomes, and three of the siRNAs (targeting elongation factor 1α, calmodulin, and α-actinin) reduced transcript levels 2.5, 3.6, and 5.0-fold, respectively, within the lamprey midsections. This is not only the first demonstration of RNAi in lampreys, but it is also the first example of delivery of siRNAs to a non-mammalian vertebrate through feeding formulations. One of the siRNA treatments also caused increased mortality of the larvae following a single feeding of siRNAs, which suggests that prolonged or multiple feedings of siRNAs could be used to kill filter-feeding larvae within streams, following development of a slow-release formulation. The genes targeted in this study are highly conserved across many species, and only serve as a proof-of-concept demonstration that siRNAs can be used in lampreys. Given that RNA interference is a sequence-specific phenomenon, it should be possible to design siRNAs that selectively target gene sequences that are unique to sea lampreys, and thus develop a technology to control these pests without adversely affecting non-target species.

  7. Occurrence of Ergasilus megaceros Wilson, 1916, in the sea lamprey and other fishes from North America

    Science.gov (United States)

    Muzzall, Patrick M.; Hudson, Patrick L.

    2004-01-01

    Ergasilus megaceros (Copepoda: Ergasilidae) was recovered from the nasal fossae (lamellae) of the olfactory sac in 1 (1.8%) of 56 sea lampreys, Petromyzon marinus Linne, 1758, collected in May 2002 from the Cheboygan River, Michigan. Although the sea lamprey is a new host record for E. megaceros, this fish species may not be a preferred host because of its low prevalence. Ergasilus megaceros is the second ergasilid species reported from the sea lamprey in North America. This is the third report of an ergasilid species infecting the nasal fossae of fishes in North America, with E. rhinos being the only other species reported from this site.

  8. Does DNA methylation regulate metamorphosis? The case of the sea lamprey (Petromyzon marinus) as an example.

    Science.gov (United States)

    Covelo-Soto, Lara; Saura, María; Morán, Paloma

    2015-07-01

    Lampreys represent one of the most ancient vertebrate lineages enclosing a special interest for genetic and epigenetic studies. The sea lamprey (Petromyzon marinus) is an anadromous species that experiences metamorphosis all the way up to the adult stage. Although representing a gradual process, metamorphosis in this species involves dramatic conversions with regard to physiological together with structural body changes preparing individuals for a marine and parasitic life; in consequence, multiple gene expression modifications are expected. The implications of thyroid hormones and HOX gene expression changes have previously been reported in this species and also in other vertebrate species. Nonetheless, information lacks on how these genes are regulated in lampreys. We here report about the existence of methylation pattern differences between the adult and the larvae sea lamprey life cycle stages making use of the Methylation-Sensitive Amplified Polymorphism (MSAP) technique. Differentially methylated fragment sequencing allowed to establish homologous identities with HOX genes involved in morphogenesis, along with genes related to the water balance and to the osmotic homoeostasis, all associated to a marine environment adaptation. These results provide evidences revealing that DNA methylation plays a role in the epigenetic regulation of the P. marinus post-natal development representing a starting point for future studies. To the best of our knowledge, this is the first study which detects DNA methylation changes associated with metamorphosis in lampreys. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Spatial mismatch between sea lamprey behaviour and trap location explains low success at trapping for control

    Science.gov (United States)

    Rous, Andrew M.; McLean, Adrienne R.; Barber, Jessica; Bravener, Gale; Castro-Santos, Theodore; Holbrook, Christopher M.; Imre, Istvan; Pratt, Thomas C.; McLaughlin, Robert L.

    2017-01-01

    Crucial to the management of invasive species is understanding space use and the environmental features affecting space use. Improved understanding of space use by invasive sea lamprey (Petromyzon marinus) could help researchers discern why trap success in large rivers is lower than needed for effective control. We tested whether manipulating discharge nightly could increase trap success at a hydroelectric generating station on the St. Marys River. We quantified numbers of acoustically tagged sea lampreys migrating up to, and their space use at, the hydroelectric generating station. In 2011 and 2012, 78% and 68%, respectively, of tagged sea lampreys reached the generating station. Sea lampreys were active along the face, but more likely to occur at the bottom and away from the traps near the surface, especially when discharge was high. Our findings suggest that a low probability of encountering traps was due to spatial (vertical) mismatch between space use by sea lamprey and trap locations and that increasing discharge did not alter space use in ways that increased trap encounter. Understanding space use by invasive species can help managers assess the efficacy of trapping and ways of improving trapping success.

  10. Distribution and seasonal differences in Pacific Lamprey and Lampetra spp eDNA across 18 Puget Sound watersheds

    Science.gov (United States)

    Ostberg, Carl O.; Chase, Dorothy M.; Hayes, Michael C.; Duda, Jeffrey J.

    2018-01-01

    Lampreys have a worldwide distribution, are functionally important to ecological communities and serve significant roles in many cultures. In Pacific coast drainages of North America, lamprey populations have suffered large declines. However, lamprey population status and trends within many areas of this region are unknown and such information is needed for advancing conservation goals. We developed two quantitative PCR-based, aquatic environmental DNA (eDNA) assays for detection of Pacific Lamprey (Entosphenus tridentatus) and Lampetra spp, using locked nucleic acids (LNAs) in the probe design. We used these assays to characterize the spatial distribution of lamprey in 18 watersheds of Puget Sound, Washington, by collecting water samples in spring and fall. Pacific Lamprey and Lampetraspp were each detected in 14 watersheds and co-occurred in 10 watersheds. Lamprey eDNA detection rates were much higher in spring compared to fall. Specifically, the Pacific Lamprey eDNA detection rate was 3.5 times higher in spring and the Lampetra spp eDNA detection rate was 1.5 times higher in spring even though larval lamprey are present in streams year-round. This significant finding highlights the importance of seasonality on eDNA detection. Higher stream discharge in the fall likely contributed to reduced eDNA detection rates, although seasonal life history events may have also contributed. These eDNA assays differentiate Pacific Lamprey and Lampetra spp across much of their range along the west coast of North America. Sequence analysis indicates the Pacific Lamprey assay also targets other Entosphenus spp and indicates the Lampetra spp assay may have limited or no capability of detecting Lampetra in some locations south of the Columbia River Basin. Nevertheless, these assays will serve as a valuable tool for resource managers and have direct application to lamprey conservation efforts, such as mapping species distributions, occupancy modeling, and monitoring

  11. Estimating reach-specific fish movement probabilities in rivers with a Bayesian state-space model: application to sea lamprey passage and capture at dams

    Science.gov (United States)

    Holbrook, Christopher M.; Johnson, Nicholas S.; Steibel, Juan P.; Twohey, Michael B.; Binder, Thomas R.; Krueger, Charles C.; Jones, Michael L.

    2014-01-01

    Improved methods are needed to evaluate barriers and traps for control and assessment of invasive sea lamprey (Petromyzon marinus) in the Great Lakes. A Bayesian state-space model provided reach-specific probabilities of movement, including trap capture and dam passage, for 148 acoustic tagged invasive sea lamprey in the lower Cheboygan River, Michigan, a tributary to Lake Huron. Reach-specific movement probabilities were combined to obtain estimates of spatial distribution and abundance needed to evaluate a barrier and trap complex for sea lamprey control and assessment. Of an estimated 21 828 – 29 300 adult sea lampreys in the river, 0%–2%, or 0–514 untagged lampreys, could have passed upstream of the dam, and 46%–61% were caught in the trap. Although no tagged lampreys passed above the dam (0/148), our sample size was not sufficient to consider the lock and dam a complete barrier to sea lamprey. Results also showed that existing traps are in good locations because 83%–96% of the population was vulnerable to existing traps. However, only 52%–69% of lampreys vulnerable to traps were caught, suggesting that traps can be improved. The approach used in this study was a novel use of Bayesian state-space models that may have broader applications, including evaluation of barriers for other invasive species (e.g., Asian carp (Hypophthalmichthys spp.)) and fish passage structures for other diadromous fishes.

  12. White sucker Catostomus commersonii respond to conspecific and sea lamprey Petromyzon marinus alarm cues but not potential predator cues

    Science.gov (United States)

    Jordbro, Ethan J.; Di Rocco, Richard T.; Imre, Istvan; Johnson, Nicholas; Brown, Grant E.

    2016-01-01

    Recent studies proposed the use of chemosensory alarm cues to control the distribution of invasive sea lamprey Petromyzon marinus populations in the Laurentian Great Lakes and necessitate the evaluation of sea lamprey chemosensory alarm cues on valuable sympatric species such as white sucker. In two laboratory experiments, 10 replicate groups (10 animals each) of migratory white suckers were exposed to deionized water (control), conspecific whole-body extract, heterospecific whole-body extract (sea lamprey) and two potential predator cues (2-phenylethylamine HCl (PEA HCl) and human saliva) during the day, and exposed to the first four of the above cues at night. White suckers avoided the conspecific and the sea lamprey whole-body extract both during the day and at night to the same extent. Human saliva did not induce avoidance during the day. PEA HCl did not induce avoidance at a higher concentration during the day, or at night at the minimum concentration that was previously shown to induce maximum avoidance by sea lamprey under laboratory conditions. Our findings suggest that human saliva and PEA HCl may be potential species-specific predator cues for sea lamprey.

  13. Anesthesia of juvenile Pacific Lampreys with MS-222, BENZOAK, AQUI-S 20E, and Aquacalm

    Science.gov (United States)

    Christiansen, Helena E.; Gee, Lisa P.; Mesa, Matthew G.

    2013-01-01

    Effective anesthetics are a critical component of safe and humane fish handling procedures. We tested three concentrations each of four anesthetics—Finquel (tricaine methanesulfonate, herein referred to as MS-222), BENZOAK (20% benzocaine), AQUI-S 20E (10% eugenol), and Aquacalm (metomidate hydrochloride)—for efficacy and safety in metamorphosed, outmigrating juvenile Pacific Lampreys Entosphenus tridentatus. The anesthetics MS-222 (100 mg/L) and BENZOAK (60 mg/L) were the most effective for anesthetizing juvenile Pacific Lampreys to a handleable state with minimal irritation to the fish. Fish anesthetized with BENZOAK also had lower rates of fungal infection than those exposed to MS-222, AQUI-S 20E, or no anesthetic. Exposure to AQUI-S 20E irritated juvenile Pacific Lampreys, causing them to leap or climb out of the anesthetic solution, and Aquacalm anesthetized fish to a handleable state too slowly and incompletely for effective use with routine handling procedures. Our results indicate that MS-222 and BENZOAK are effective anesthetics for juvenile Pacific Lampreys, but field studies are needed to determine whether exposure to MS-222 increases risk of fungal infection in juvenile Pacific Lampreys released to the wild.

  14. Evaluate Status of Pacific Lamprey in the Clearwater River Drainage, Idaho, Annual Report 2002.

    Energy Technology Data Exchange (ETDEWEB)

    Cochnauer, Tim; Claire, Christopher

    2003-10-01

    In 2002 Idaho Department of Fish and Game continued investigation into the status of Pacific lamprey populations in Idaho's Clearwater River drainage. Trapping, electrofishing, and spawning ground redd surveys were used to determine Pacific lamprey distribution, life history strategies, and habitat requirements in the South Fork Clearwater River, Lochsa River, Selway River, and Middle Fork Clearwater River subbasins. Five-hundred forty-one ammocoetes were captured electroshocking 70 sites in the South Fork Clearwater River, Lochsa River, Selway River, Middle Fork Clearwater River, Clearwater River, and their tributaries in 2002. Habitat utilization surveys in Red River support previous work indicating Pacific lamprey ammocoete densities are greater in lateral scour pool habitats compared to riffles and rapids. Presence-absence survey findings in 2002 augmented 2000 and 2001 indicating Pacific lamprey macrothalmia and ammocoetes are not numerous or widely distributed. Pacific lamprey distribution was confined to the lower reaches of Red River below rkm 8.0, the South Fork Clearwater River, Lochsa River (Ginger Creek to mouth), Selway River (Race Creek to mouth), Middle Fork Clearwater River, and the Clearwater River (downstream to Potlatch River).

  15. Test of a non-physical barrier consisting of light, sound, and bubble screen to block upstream movement of sea lamprey in an experimental raceway

    Science.gov (United States)

    Miehls, Scott M.; Johnson, Nicholas S.; Hrodey, Pete J.

    2017-01-01

    Control of the invasive Sea Lamprey Petromyzon marinus is critical for management of commercial and recreational fisheries in the Laurentian Great Lakes. Use of physical barriers to block Sea Lampreys from spawning habitat is a major component of the control program. However, the resulting interruption of natural streamflow and blockage of nontarget species present substantial challenges. Development of an effective nonphysical barrier would aid the control of Sea Lampreys by eliminating their access to spawning locations while maintaining natural streamflow. We tested the effect of a nonphysical barrier consisting of strobe lights, low-frequency sound, and a bubble screen on the movement of Sea Lampreys in an experimental raceway designed as a two-choice maze with a single main channel fed by two identical inflow channels (one control and one blocked). Sea Lampreys were more likely to move upstream during trials when the strobe light and low-frequency sound were active compared with control trials and trials using the bubble screen alone. For those Sea Lampreys that did move upstream to the confluence of inflow channels, no combination of stimuli or any individual stimulus significantly influenced the likelihood that Sea Lampreys would enter the blocked inflow channel, enter the control channel, or return downstream.

  16. Evidence that lake trout served as a buffer against sea lamprey predation on burbot in Lake Erie

    Science.gov (United States)

    Stapanian, M.A.; Madenjian, C.P.

    2007-01-01

    The population of burbot Lota lota in Lake Erie recovered during 1986–2003, mainly because of the control of sea lamprey Petromyzon marinus, which began in 1986. Burbot populations continued to grow during 1996–1998, when sea lamprey control was substantially reduced. We calculated mortality parameters for burbot in Lake Erie by estimating age at capture for 2,793 burbot caught in annual gill-net surveys of eastern Lake Erie from 1994 to 2003. Based on catch-curve analysis, annual mortality in Lake Erie during 1994–2003 was estimated as 33%. Annual mortality of the 1992 year-class of burbot was estimated as 30%. The mortality of burbot during the years of reduced sea lamprey control was not different from that during the 3 years preceding reduced control and was significantly lower than that during the entire portion of the time series in which full sea lamprey control was conducted. These results suggest that the reduction in sea lamprey control did not lead to increased burbot mortality. The catch per gill-net lift of large burbot (total length > 600 mm), the size preferred by sea lampreys, was lower than that of adult lake trout Salvelinus namaycush (age 5 and older; total length > 700 mm) before lampricide application was reduced. Although adult lake trout populations declined, the abundance of large burbot did not change during the period of reduced lampricide application. These results support a hypothesis that a healthy population of adult lake trout can serve as a buffer species, acting to reduce predation of burbot by sea lampreys when sea lamprey populations increase. Burbot attained sexual maturity at a relatively early age (3 or 4 years) and a total length (approximately 500 mm) that was smaller than the preferred prey size for sea lampreys. These characteristics and the buffering effect of the lake trout population enabled growth of the burbot population during the brief period when lamprey control was reduced.

  17. Anadromous sea lampreys recolonize a Maine coastal river tributary after dam removal

    Science.gov (United States)

    Hogg, Robert; Coghlan, Stephen M.; Zydlewski, Joseph D.

    2013-01-01

    Sedgeunkedunk Stream, a third-order tributary to the Penobscot River, Maine, historically supported several anadromous fishes, including the Atlantic Salmon Salmo salar, AlewifeAlosa pseudoharengus, and Sea Lamprey Petromyzon marinus. However, two small dams constructed in the 1800s reduced or eliminated spawning runs entirely. In 2009, efforts to restore marine–freshwater connectivity in the system culminated with removal of the lowermost dam, thus providing access to an additional 4.6 km of lotic habitat. Because Sea Lampreys utilized accessible habitat prior to dam removal, they were chosen as a focal species with which to quantify recolonization. During spawning runs of 2008–2011 (before and after dam removal), individuals were marked with PIT tags and their activity was tracked with daily recapture surveys. Open-population mark–recapture models indicated a fourfold increase in the annual abundance of spawning-phase Sea Lampreys, with estimates rising from 59±4 () before dam removal (2008) to 223±18 and 242±16 after dam removal (2010 and 2011, respectively). Accompanying the marked increase in annual abundance was a greater than fourfold increase in nesting sites: the number of nests increased from 31 in 2008 to 128 and 131 in 2010 and 2011, respectively. During the initial recolonization event (i.e., in 2010), Sea Lampreys took 6 d to move past the former dam site and 9 d to expand into the furthest upstream reaches. Conversely, during the 2011 spawning run, Sea Lampreys took only 3 d to penetrate into the upstream reaches, thus suggesting a potential positive feedback in which larval recruitment into the system may have attracted adult spawners via conspecific pheromone cues. Although more research is needed to verify the migratory pheromone hypothesis, our study clearly demonstrates that small-stream dam removal in coastal river systems has the potential to enhance recovery of declining anadromous fish populations.

  18. Pacific Lamprey Research and Restoration Project : Annual Report 2001.

    Energy Technology Data Exchange (ETDEWEB)

    Close, David A.

    2002-11-01

    Pacific lamprey (Lampetra tridentata) has significantly declined along the Oregon coast and in the Columbia River Basin (Downey et al. 1993; Close and Jackson 2001). Declines in adults can be partially attributed to hydroelectric dams, which have impeded passage of adult Pacific lamprey in the Columbia and Snake rivers, thus effecting larval recruitment in the basin. Adult pacific lamprey also declined in numbers in the Umatilla River, a tributary of the Columbia River. In addition to hydro power dams in the Columbia River, habitat alterations and chemical treatments have been involved in the collapse of Pacific lamprey populations in the Umatilla River. To initiate the restoration effort, CTUIR began developing a restoration plan in 1998. The goal of the lamprey research and restoration project is to restore natural production of Pacific lampreys in the Umatilla River to self-sustaining and harvestable level. This report is summarizing the studies and restoration efforts concluded in 2001.

  19. The effect of rapid and sustained decompression on barotrauma in juvenile brook lamprey and Pacific lamprey: implications for passage at hydroelectric facilities

    Energy Technology Data Exchange (ETDEWEB)

    Colotelo, Alison HA; Pflugrath, Brett D.; Brown, Richard S.; Brauner, Colin J.; Mueller, Robert P.; Carlson, Thomas J.; Deng, Zhiqun; Ahmann, Martin L.; Trumbo, Bradly A.

    2012-10-01

    Fish passing downstream through hydroelectric facilities may pass through hydroturbines where they experience a rapid decrease in barometric pressure as they pass by turbine blades, which can lead to barotraumas including swim bladder rupture, exopthalmia, emboli, and hemorrhaging. In juvenile Chinook salmon, the main mechanism for injury is thought to be expansion of existing gases (particularly those present in the swim bladder) and the rupture of the swim bladder ultimately leading to exopthalmia, emboli and hemorrhaging. In fish that lack a swim bladder, such as lamprey, the rate and severity of barotraumas due to rapid decompression may be reduced however; this has yet to be extensively studied. Another mechanism for barotrauma can be gases coming out of solution and the rate of this occurrence may vary among species. In this study, juvenile brook and Pacific lamprey acclimated to 146.2 kPa (equivalent to a depth of 4.6 m) were subjected to rapid (<1 sec; brook lamprey only) or sustained decompression (17 minutes) to a very low pressure (13.8 kPa) using a protocol previously applied to juvenile Chinook salmon. No mortality or evidence of barotraumas, as indicated by the presence of hemorrhages, emboli or exopthalmia, were observed during rapid or sustained decompression, nor following recovery for up to 120 h following sustained decompression. In contrast, mortality or injury would be expected for 97.5% of juvenile Chinook salmon exposed to a similar rapid decompression to these very low pressures. Additionally, juvenile Chinook salmon experiencing sustained decompression died within 7 minutes, accompanied by emboli in the fins and gills and hemorrhaging in the tissues. Thus, juvenile lamprey may not be susceptible to barotraumas associated with hydroturbine passage to the same degree as juvenile salmonids, and management of these species should be tailored to their specific morphological and physiological characteristics.

  20. Pacific Lamprey Research and Restoration : Annual Report 1997.

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Aaron D.; Hatch, Douglas R.; Close, David A.

    1998-08-05

    The once abundant stocks of Pacific lamprey (Lampetra tridentata) above Bonneville Dam are currently depressed (Close et al. 1995). It is likely that many of the same factors that led to the decline of wild stocks of Columbia River Pacific salmon and steelhead have impacted Pacific lamprey populations as well. The Pacific Lamprey Research and Restoration Project, funded by Bonneville Power Administration, is a cooperative effort between the Confederated Tribes of the Umatilla Indian Reservation, the Columbia River Inter-Tribal Fish Commission, and Oregon State University with the goal to increase Pacific lamprey stocks above Bonneville Dam.

  1. Cadmium determination in Lentinus edodes mushroom species

    Directory of Open Access Journals (Sweden)

    Vera Akiko Maihara

    2012-09-01

    Full Text Available Many studies have drawn attention to the occurrence and concentration of toxic elements found in the fruiting body of mushrooms. Some edible mushroom species are known to accumulate high levels of inorganic contaminants, mainly cadmium, mercury, and lead. There are about 2,000 known edible mushroom species, but only 25 of them are cultivated and used as food. In Brazil, the most marketed and consumed mushroom species are Agaricus bisporus, known as Paris champignon, Lentinus edodes, or Shitake and Pleurotus sp, also called Shimeji or Hiratake. In this study, the concentration of cadmium was determined in Lentinus edodes mushrooms from different cities in São Paulo state and some samples imported from Japan and China. The analyses were performed by graphite furnace atomic absorption spectrometry after HNO3-H2O2 digestion. The results showed a lower concentration of Cd in the mushrooms cultivated in São Paulo (0.0079 to 0.023 mg.kg-1 in natura than that of the mushrooms cultivated abroad (0.125 to 0.212 mg.kg-1 in natura. Although there is no tolerance limit for Cd in mushrooms in Brazil, the results show that Lentinus edodes mushrooms can be safely consumed.

  2. Genetic diversity, endemism and phylogeny of lampreys within the genus Lampetra sensu stricto (Petromyzontiformes: Petromyzontidae) in western North America.

    Science.gov (United States)

    Boguski, D A; Reid, S B; Goodman, D H; Docker, M F

    2012-11-01

    Phylogenetic structure of four Lampetra species from the Pacific drainage of North America (western brook lamprey Lampetra richardsoni, Pacific brook lamprey Lampetra pacifica, river lamprey Lampetra ayresii and Kern brook lamprey Lampetra hubbsi) and unidentified Lampetra specimens (referred to as Lampetra sp.) from 36 locations was estimated using the mitochondrial cytochrome b gene. Maximum parsimony and Bayesian inferences did not correspond with any taxonomic scheme proposed to date. Rather, although L. richardsoni (from Alaska to California) and L. ayresii (from British Columbia to California) together constituted a well-supported clade distinct from several genetically divergent Lampetra populations in Oregon and California, these two species were not reciprocally monophyletic. The genetically divergent populations included L. pacifica (from the Columbia River basin) and L. hubbsi (from the Kern River basin) and four Lampetra sp. populations in Oregon (Siuslaw River and Fourmile Creek) and California (Kelsey and Mark West Creeks). These four Lampetra sp. populations showed genetic divergence between 2.3 and 5.7% from any known species (and up to 8.0% from each other), and may represent morphologically cryptic and thus previously undescribed species. A fifth population (from Paynes Creek, California) may represent a range extension of L. hubbsi into the Upper Sacramento River. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  3. Metabolism of a sea lamprey pesticide by fish liver enzymes part A: identification and synthesis of TFM metabolites.

    Science.gov (United States)

    Bussy, Ugo; Chung-Davidson, Yu-Wen; Buchinger, Tyler; Li, Ke; Smith, Scott A; Jones, A Daniel; Li, Weiming

    2018-02-01

    The sea lamprey (Petromyzon marinus) is a destructive invasive species in the Great Lakes that contributed to the collapse of native fish populations in the mid-1900s. 3-Trifluoromethyl-4-nitrophenol (TFM) is a selective pesticide that has been applied to sea lamprey infested tributaries of the Great Lakes to kill larvae since the 1960s and has reduced the populations by as much as 90%. However, the metabolism of TFM by sea lamprey and non-target species is not fully illuminated. Elucidation of TFM metabolism is critical for understanding its mode of action and possible environmental impact. Here, we describe the screening, identification, synthesis and structural characterization of TFM metabolites in livers from sea lamprey and three non-target species that differ in their ability to survive TFM exposure. We identified glucuronidation, sulfation, N-acetylation, glutathione conjugation, and aromatic nitro group reduction as potential detoxification mechanisms. Seven metabolites were synthesized for use as markers of TFM metabolism in fish. Quantitative 1 H NMR was used to assay synthesized metabolite stock solutions that were then used as standard material to develop a quantitative LC-MS/MS method for TFM metabolites.

  4. Pacific Lamprey Research and Restoration Project : Annual Report 2000.

    Energy Technology Data Exchange (ETDEWEB)

    Close, David A.

    2002-11-01

    This report summarizes results of research activities conducted in 1999-2000. The findings in these chapters represent the efforts of the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) and collaborative efforts among other researchers working on Pacific lampreys (Lampetra tridentata) under this project. The findings in these chapters will help management and recovery of Pacific lampreys in the Columbia River Basin.

  5. Regulation of a putative corticosteroid, 17, 21-dihydroxypregn-4-ene, 3, 20-one, in sea lamprey, Petromyzon marinus.

    Science.gov (United States)

    Roberts, Brent W.; Didier, Wes; Satbir, Rai; Johnson, Nicholas S.; Libants, Scot V.; Sang-Seon, Yun; Close, David

    2013-01-01

    In higher vertebrates, in response to stress, the hypothalamus produces corticotropin-releasing hormone (CRH), which stimulates cells in the anterior pituitary to produce adrenocorticotropic hormone (ACTH), which in turn stimulates production of either cortisol (F) or corticosterone (B) by the adrenal tissues. In lampreys, however, neither of these steroids is present. Instead, it has been proposed that the stress steroid is actually 17,21-dihydroxypregn-4-ene-3,20-dione (11-deoxycortisol; S). However, there have been no studies yet to determine its mechanism of regulation or site of production. Here we demonstrate that (1) intraperitoneal injections of lamprey-CRH increase plasma S in a dose dependent manner, (2) intraperitoneal injections of four lamprey-specific ACTH peptides at 100 lg/kg, did not induce changes in plasma S concentrations in either males or females; (3) two lamprey-specific gonadotropin-releasing hormones (GnRH I and III) and arginine-vasotocin (AVT), all at single doses, stimulated S production as well as, or to an even greater extent than CRH; (4) sea lamprey mesonephric kidneys, in vitro, converted tritiated 17a-hydroxyprogesterone (17a-P) into a steroid that had the same chromatographic properties (on HPLC and TLC) as S; (5) kidney tissues released significantly more immunoassayable S into the incubation medium than gill, liver or gonad tissues. One interpretation of these results is that the corticosteroid production of the sea lamprey, one of the oldest extant vertebrates, is regulated through multiple pathways rather than the classical HPI-axis. However, the responsiveness of this steroid to the GnRH peptides means that a reproductive rather than a stress role for this steroid cannot yet be ruled out.

  6. Reconnaissance of contaminants in larval Pacific lamprey (Entosphenus tridentatus) tissues and habitats in the Columbia River Basin, Oregon and Washington, USA

    Science.gov (United States)

    Nilsen, Elena B.; Hapke, Whitney B.; McIlraith, Brian; Markovchick, Dennis J.

    2015-01-01

    Pacific lampreys (Entosphenus tridentatus) have resided in the Columbia River Basin for millennia and have great ecological and cultural importance. The role of habitat contamination in the recent decline of the species has rarely been studied and was the main objective of this effort. A wide range of contaminants (115 analytes) was measured in sediments and tissues at 27 sites across a large geographic area of diverse land use. This is the largest dataset of contaminants in habitats and tissues of Pacific lamprey in North America and the first study to compare contaminant bioburden during the larval life stage and the anadromous, adult portion of the life cycle. Bioaccumulation of pesticides, flame retardants, and mercury was observed at many sites. Based on available data, contaminants are accumulating in larval Pacific lamprey at levels that are likely detrimental to organism health and may be contributing to the decline of the species.

  7. Analysis of DNA damage in sea lamprey (Petromyzon marinus) spermatozoa by UV, hydrogen peroxide, and the toxicant bisazir

    International Nuclear Information System (INIS)

    Ciereszko, Andrzej; Wolfe, Tobie D.; Dabrowski, Konrad

    2005-01-01

    In this study we sought to demonstrate that Comet assay can be applied to sea lamprey sperm DNA fragmentation and used to describe the relationship between sperm DNA damage and sperm fertilizing ability. We show that the assay can be used reliably and accurately, and unlike in the case of mammals, there is no need for additional steps related to improvement of efficacy of lysis and DNA decondensation. This agrees with the presence of histone proteins in lamprey sperm. An increase in DNA fragmentation was noted during short-term storage of milt on ice (0-4 days). We demonstrated genotoxic effects of UV radiation and oxidative stress (exposure to hydrogen peroxide) and found that oxidative damage to sperm DNA was likely repaired after fertilization in the embryo. Repairing capacity of the oocyte toward sperm DNA lesions caused by UV was restricted. Toxic effect of p,p-bis-(1-aziridinyl)-N-methylphosphinothioic acid (p,p-bis(1-aziridinyl)-N-methylphosphinothioic amide), a sea lamprey chemosterilant, could not be linked to DNA fragmentation in the in vitro tests. Its genotoxicity in vivo may possibly be associated with other mechanisms of DNA degradation (oxidation or DNA-protein and DNA-DNA cross-linking). In conclusion, this study demonstrates that Comet assay can be successfully applied to monitor effects of environmental disturbances and imposed injuries in sea lamprey spermatozoa and possibly other species of ancient fish with acrosomal sperm

  8. Analysis of DNA damage in sea lamprey (Petromyzon marinus) spermatozoa by UV, hydrogen peroxide, and the toxicant bisazir

    Energy Technology Data Exchange (ETDEWEB)

    Ciereszko, Andrzej [School of Natural Resources, Ohio State University, 210 Kottman Hall, 2021 Coffey Rd., Columbus, OH 434210 (United States); Semen Biology Group, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, 10-747 Olsztyn (Poland); Wolfe, Tobie D. [School of Natural Resources, Ohio State University, 210 Kottman Hall, 2021 Coffey Rd., Columbus, OH 434210 (United States); Dabrowski, Konrad [School of Natural Resources, Ohio State University, 210 Kottman Hall, 2021 Coffey Rd., Columbus, OH 434210 (United States)]. E-mail: dabrowski.1@osu.edu

    2005-06-15

    In this study we sought to demonstrate that Comet assay can be applied to sea lamprey sperm DNA fragmentation and used to describe the relationship between sperm DNA damage and sperm fertilizing ability. We show that the assay can be used reliably and accurately, and unlike in the case of mammals, there is no need for additional steps related to improvement of efficacy of lysis and DNA decondensation. This agrees with the presence of histone proteins in lamprey sperm. An increase in DNA fragmentation was noted during short-term storage of milt on ice (0-4 days). We demonstrated genotoxic effects of UV radiation and oxidative stress (exposure to hydrogen peroxide) and found that oxidative damage to sperm DNA was likely repaired after fertilization in the embryo. Repairing capacity of the oocyte toward sperm DNA lesions caused by UV was restricted. Toxic effect of p,p-bis-(1-aziridinyl)-N-methylphosphinothioic acid (p,p-bis(1-aziridinyl)-N-methylphosphinothioic amide), a sea lamprey chemosterilant, could not be linked to DNA fragmentation in the in vitro tests. Its genotoxicity in vivo may possibly be associated with other mechanisms of DNA degradation (oxidation or DNA-protein and DNA-DNA cross-linking). In conclusion, this study demonstrates that Comet assay can be successfully applied to monitor effects of environmental disturbances and imposed injuries in sea lamprey spermatozoa and possibly other species of ancient fish with acrosomal sperm.

  9. Migratory behavior of adult sea lamprey and cumulative passage performance through four fishways

    Science.gov (United States)

    Castro-Santos, Theodore R.; Shi, Xiaotao; Haro, Alexander

    2017-01-01

    This article describes a study of PIT-tagged sea lamprey (Petromyzon marinus) ascending four fishways comprising three designs at two dams on the Connecticut River, USA. Migration between dams was rapid (median migration rate = 23 km·day−1). Movement through the fishways was much slower, however (median = 0.02–0.33 km·day−1). Overall delay at dams was substantial (median = 13.6–14.6 days); many fish failed to pass (percent passage ranged from 29% to 55%, depending on fishway), and repeated passage attempts compounded delay for both passers and failers. Cox regression revealed that fishway entry rates were influenced by flow, temperature, and diel cycle, with most lampreys entering at night and at elevated flows, but with no apparent effect of sex or length. Overall delay was influenced by slow movement through the fishways, but repeated failures were the primary factor determining delay. These data suggest that although some lamprey were able to pass fishways, they did so with difficulty, and delays incurred as they attempted to pass may act to limit their distribution within their native range.

  10. Pacific lamprey research and restoration project: annual report 1999; ANNUAL

    International Nuclear Information System (INIS)

    Close, David A.

    2001-01-01

    This report summarizes results of research activities conducted from 1996 through 1999. The findings in these chapters represent the efforts of the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) and collaborative efforts among other researchers working on Pacific lampreys (Lampetra tridentata) under this project. The findings in these chapters will help management and recovery of Pacific lampreys in the Columbia River Basin. Traditional Ecological Knowledge (TEK) of Pacific lampreys from tribal members within the Confederated Tribes of the Umatilla Indian Reservation was useful in gaining baseline life history information. Tribal members described harvesting two types of lampreys from spring through fall, the short brown type and the long dark type. Lamprey spawning distribution was from the mouth to the headwaters in the Umatilla River. Larval lampreys were observed in the mud and sand areas of the river. Tribal members observed major declines in lampreys within the Columbia River basin. Larval Pacific lampreys were distributed throughout the John Day River basin. Larval distribution in the other subbasins was patchy and limited to the lower reaches of the streams. Larval densities were highly variable in the Middle Fork John Day and North Fork John Day rivers, as opposed to the Main stem John Day River. Larval lengths varied little in the Middle Fork John Day and North Fork John Day rivers, but were highly variable in the Main stem John Day River. Larval abundance decreased as we moved upstream in the Columbia and Snake rivers. In addition, we found strong evidence for lack of larval recruitment as distance increased from the mouth of the Columbia River. We identified clinical indicators of stress in adult Pacific lampreys. Plasma glucose became elevated soon after acute stress and remained elevated for one week. Plasma lactate also became elevated by 30 minutes; however, it decreased to resting levels by one hour after application of the stressor

  11. Pacific Lamprey Research and Restoration Project : Annual Report 1999.

    Energy Technology Data Exchange (ETDEWEB)

    Close, David A.

    2001-10-01

    This report summarizes results of research activities conducted from 1996 through 1999. The findings in these chapters represent the efforts of the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) and collaborative efforts among other researchers working on Pacific lampreys (Lampetra tridentata) under this project. The findings in these chapters will help management and recovery of Pacific lampreys in the Columbia River Basin. Traditional Ecological Knowledge (TEK) of Pacific lampreys from tribal members within the Confederated Tribes of the Umatilla Indian Reservation was useful in gaining baseline life history information. Tribal members described harvesting two types of lampreys from spring through fall, the short brown type and the long dark type. Lamprey spawning distribution was from the mouth to the headwaters in the Umatilla River. Larval lampreys were observed in the mud and sand areas of the river. Tribal members observed major declines in lampreys within the Columbia River basin. Larval Pacific lampreys were distributed throughout the John Day River basin. Larval distribution in the other subbasins was patchy and limited to the lower reaches of the streams. Larval densities were highly variable in the Middle Fork John Day and North Fork John Day rivers, as opposed to the Main stem John Day River. Larval lengths varied little in the Middle Fork John Day and North Fork John Day rivers, but were highly variable in the Main stem John Day River. Larval abundance decreased as we moved upstream in the Columbia and Snake rivers. In addition, we found strong evidence for lack of larval recruitment as distance increased from the mouth of the Columbia River. We identified clinical indicators of stress in adult Pacific lampreys. Plasma glucose became elevated soon after acute stress and remained elevated for one week. Plasma lactate also became elevated by 30 minutes; however, it decreased to resting levels by one hour after application of the stressor

  12. Pacific Lamprey Research and Restoration Project, Annual Report 2002.

    Energy Technology Data Exchange (ETDEWEB)

    Close, David; Aronsuu, Kimmo; Jackson, Aaron

    2003-07-01

    Pacific lamprey (Lampetra tridentata) has significantly declined along the Oregon coast and in the Columbia River Basin (Downey et al. 1993, Close and Jackson 2001). Declines in adults can be partially attributed to hydroelectric dams, which have impeded passage of adult Pacific lamprey in the Columbia and Snake rivers (Moser et al. 2002), thus effecting larval recruitment in the basin (Moser and Close in press). Adult Pacific lamprey also declined in numbers in the Umatilla River, a tributary of the Columbia River (Close and Jackson 2001). In addition to hydro power dams in the Columbia River, habitat alterations and chemical treatments have been involved in the collapse of Pacific lamprey populations in the Umatilla River (Close 1999). To initiate the restoration effort, CTUIR began developing a restoration plan in 1998. The goal of the lamprey research and restoration project is to restore natural production of Pacific lampreys in the Umatilla River to self-sustaining and harvestable level. This report is summarizing the studies and restoration efforts concluded in 2002.

  13. Geographic range size and determinants of avian species richness

    DEFF Research Database (Denmark)

    Jetz, Walter; Rahbek, Carsten

    2002-01-01

    Geographic patterns in species richness are mainly based on wide-ranging species because their larger number of distribution records has a disproportionate contribution to the species richness counts. Here we demonstrate how this effect strongly influences our understanding of what determines spe...

  14. Neural crest contributions to the lamprey head

    Science.gov (United States)

    McCauley, David W.; Bronner-Fraser, Marianne

    2003-01-01

    The neural crest is a vertebrate-specific cell population that contributes to the facial skeleton and other derivatives. We have performed focal DiI injection into the cranial neural tube of the developing lamprey in order to follow the migratory pathways of discrete groups of cells from origin to destination and to compare neural crest migratory pathways in a basal vertebrate to those of gnathostomes. The results show that the general pathways of cranial neural crest migration are conserved throughout the vertebrates, with cells migrating in streams analogous to the mandibular and hyoid streams. Caudal branchial neural crest cells migrate ventrally as a sheet of cells from the hindbrain and super-pharyngeal region of the neural tube and form a cylinder surrounding a core of mesoderm in each pharyngeal arch, similar to that seen in zebrafish and axolotl. In addition to these similarities, we also uncovered important differences. Migration into the presumptive caudal branchial arches of the lamprey involves both rostral and caudal movements of neural crest cells that have not been described in gnathostomes, suggesting that barriers that constrain rostrocaudal movement of cranial neural crest cells may have arisen after the agnathan/gnathostome split. Accordingly, neural crest cells from a single axial level contributed to multiple arches and there was extensive mixing between populations. There was no apparent filling of neural crest derivatives in a ventral-to-dorsal order, as has been observed in higher vertebrates, nor did we find evidence of a neural crest contribution to cranial sensory ganglia. These results suggest that migratory constraints and additional neural crest derivatives arose later in gnathostome evolution.

  15. Neither philopatric nor panmictic: microsatellite and mtDNA evidence suggests lack of natal homing but limits to dispersal in Pacific lamprey.

    Science.gov (United States)

    Spice, Erin K; Goodman, Damon H; Reid, Stewart B; Docker, Margaret F

    2012-06-01

    Most species with lengthy migrations display some degree of natal homing; some (e.g. migratory birds and anadromous salmonids) show spectacular feats of homing. However, studies of the sea lamprey (Petromyzon marinus) indicate that this anadromous species locates spawning habitat based on pheromonal cues from larvae rather than through philopatry. Previous genetic studies in the anadromous Pacific lamprey (Entosphenus tridentatus) have both supported and rejected the hypothesis of natal homing. To resolve this, we used nine microsatellite loci to examine the population structure in 965 Pacific lamprey from 20 locations from central British Columbia to southern California and supplemented this analysis with mitochondrial DNA restriction fragment length polymorphism analysis on a subset of 530 lamprey. Microsatellite analysis revealed (i) relatively low but often statistically significant genetic differentiation among locations (97% pairwise F(ST) values were <0.04 but 73.7% were significant); and (ii) weak but significant isolation by distance (r(2) = 0.0565, P = 0.0450) but no geographic clustering of samples. The few moderate F(ST) values involved comparisons with sites that were geographically distant or far upstream. The mtDNA analysis--although providing less resolution among sites (only 4.7%F(ST) values were significant)--was broadly consistent with the microsatellite results: (i) the southernmost site and some sites tributary to the Salish Sea were genetically distinct; and (ii) southern sites showed higher haplotype and private haplotype richness. These results are inconsistent with philopatry, suggesting that anadromous lampreys are unusual among species with long migrations, but suggest that limited dispersal at sea precludes panmixia in this species. © 2012 Blackwell Publishing Ltd.

  16. Dopamine and the Brainstem Locomotor Networks: From Lamprey to Human

    Directory of Open Access Journals (Sweden)

    Dimitri Ryczko

    2017-05-01

    Full Text Available In vertebrates, dopamine neurons are classically known to modulate locomotion via their ascending projections to the basal ganglia that project to brainstem locomotor networks. An increased dopaminergic tone is associated with increase in locomotor activity. In pathological conditions where dopamine cells are lost, such as in Parkinson's disease, locomotor deficits are traditionally associated with the reduced ascending dopaminergic input to the basal ganglia. However, a descending dopaminergic pathway originating from the substantia nigra pars compacta was recently discovered. It innervates the mesencephalic locomotor region (MLR from basal vertebrates to mammals. This pathway was shown to increase locomotor output in lampreys, and could very well play an important role in mammals. Here, we provide a detailed account on the newly found dopaminergic pathway in lamprey, salamander, rat, monkey, and human. In lampreys and salamanders, dopamine release in the MLR is associated with the activation of reticulospinal neurons that carry the locomotor command to the spinal cord. Dopamine release in the MLR potentiates locomotor movements through a D1-receptor mechanism in lampreys. In rats, stimulation of the substantia nigra pars compacta elicited dopamine release in the pedunculopontine nucleus, a known part of the MLR. In a monkey model of Parkinson's disease, a reduced dopaminergic innervation of the brainstem locomotor networks was reported. Dopaminergic fibers are also present in human pedunculopontine nucleus. We discuss the conserved locomotor role of this pathway from lamprey to mammals, and the hypothesis that this pathway could play a role in the locomotor deficits reported in Parkinson's disease.

  17. Conservation challenges and research needs for Pacific lamprey in the Columbia River Basin

    Science.gov (United States)

    Clemens, Benjamin J.; Beamish, Richard J.; Coates, Kelly C.; Docker, Margaret F.; Dunham, Jason B.; Gray, Ann E.; Hess, Jon E.; Jolley, Jeffrey C.; Lampman, Ralph T.; McIlraith, Brian J.; Moser, Mary L.; Murauskas, Joshua G.; Noakes, David L. G.; Schaller, Howard A.; Schreck, Carl B.; Starcevich, Steven J.; Streif, Bianca; van de Wetering, Stan J.; Wade, Joy; Weitkamp, Laurie A.; Wyss, Lance A.

    2017-01-01

    The Pacific Lamprey Entosphenus tridentatus, an anadromous fish native to the northern Pacific Ocean and bordering freshwater habitats, has recently experienced steep declines in abundance and range contractions along the West Coast of North America. During the early 1990s, Native American tribes recognized the declining numbers of lamprey and championed their importance. In 2012, 26 entities signed a conservation agreement to coordinate and implement restoration and research for Pacific Lamprey. Regional plans have identified numerous threats, monitoring needs, and strategies to conserve and restore Pacific Lamprey during their freshwater life stages. Prime among these are needs to improve lamprey passage, restore freshwater habitats, educate stakeholders, and implement lamprey-specific research and management protocols. Key unknowns include range-wide trends in status, population dynamics, population delineation, limiting factors, and marine influences. We synthesize these key unknowns, with a focus on the freshwater life stages of lamprey in the Columbia River basin.

  18. Quantification of a male sea lamprey pheromone in tributaries of Laurentian Great Lakes by liquid chromatography-tandem mass spectrometry

    Science.gov (United States)

    Xi, X.; Johnson, N.S.; Brant, C.O.; Yun, S.-S.; Chambers, K.L.; Jones, A.D.; Li, W.

    2011-01-01

    We developed an assay for measuring 7α,12α,24-trihydroxy-5a-cholan-3-one-24-sulfate (3kPZS), a mating pheromone released by male sea lampreys (Petromyzon marinus), at low picomolar concentrations in natural waters to assess the presence of invasive populations. 3kPZS was extracted from streamwater at a rate of recovery up to 90% using a single cation-exchange and reversed-phase mixed-mode cartridge, along with [2H5]3kPZS as an internal standard, and quantified using ultrahigh performance liquid chromatography-tandem mass spectrometry. The limit of detection was below 0.1 ng L–1 (210 fM), which was the lowest concentration tested. Intra- and interday coefficients of variation were between 0.3–11.6% and 4.8–9.8%, respectively, at 1 ng 3kPZS L–1 and 5 ng 3kPZS L–1. This assay was validated by repeat measurements of water samples from a stream spiked with synthesized 3kPZS to reach 4.74 ng L–1 or 0.24 ng L–1. We further verified the utility of this assay to detect spawning populations of lampreys; in the seven tributaries to the Laurentian Great Lakes sampled, 3kPZS concentrations were found to range between 0.15 and 2.85 ng L–1 during the spawning season in known sea lamprey infested segments and were not detectable in uninfested segments. The 3kPZS assay may be useful for the integrated management of sea lamprey, an invasive species in the Great Lakes where pheromone-based control and assessment techniques are desired.

  19. Species identification and sex determination of the genus Nepenthes (Nepenthaceae).

    Science.gov (United States)

    Mokkamul, Piya; Chaveerach, Arunrat; Sudmoon, Runglawan; Tanee, Tawatchai

    2007-02-15

    Nepenthes species are well known for their ornamentally attractive pitchers. The species diversity was randomly surveyed in some conservation areas of Thailand and three species were found, namely N. gracilis Korth., N. mirabilis Druce. and N. smilesii Hemsl. Young plants as unknown species from Chatuchak market were added in plant sampled set. Thirty two Inter Simple Sequence Repeat (ISSR) primers were screened and 13 successful primers were used to produce DNA banding patterns for constructing a dendrogram. The dendrogram is potentially power tool to identify unknown species from Chatuchak market, differentiate species population, population by geographical areas and sex determination. The geographical area of N. mirabilis was specified to Southern and Northeastern regions and finally, subdivided into exact areas according to province. Male and female plants of N. gracilis at Phu Wua Wildlife Sanctuary and N. mirabilis at Bung Khonglong non-hunting area were determined. Two unknown species from Chatuchak market were analyzed to be N. mirabilis with the genetic similarities (S) 77.2 to 84.7. Be more sex specific in all sample studied, 37 Random Amplified Polymorphic DNA (RAPD) primers were investigated. The result shows that only one RAPD primer show high resolution results at about 750 bp specific male-related marker.

  20. Bioenergetics models to estimate numbers of larval lampreys consumed by smallmouth bass in Elk Creek, Oregon

    Science.gov (United States)

    Schultz, Luke; Heck, Michael; Kowalski, Brandon M; Eagles-Smith, Collin A.; Coates, Kelly C.; Dunham, Jason B.

    2017-01-01

    Nonnative fishes have been increasingly implicated in the decline of native fishes in the Pacific Northwest. Smallmouth Bass Micropterus dolomieu were introduced into the Umpqua River in southwest Oregon in the early 1960s. The spread of Smallmouth Bass throughout the basin coincided with a decline in counts of upstream-migrating Pacific Lampreys Entosphenus tridentatus. This suggested the potential for ecological interactions between Smallmouth Bass and Pacific Lampreys, as well as freshwater-resident Western Brook Lampreys Lampetra richardsoni. To evaluate the potential effects of Smallmouth Bass on lampreys, we sampled diets of Smallmouth Bass and used bioenergetics models to estimate consumption of larval lampreys in a segment of Elk Creek, a tributary to the lower Umpqua River. We captured 303 unique Smallmouth Bass (mean: 197 mm and 136 g) via angling in July and September. We combined information on Smallmouth Bass diet and energy density with other variables (temperature, body size, growth, prey energy density) in a bioenergetics model to estimate consumption of larval lampreys. Larval lampreys were found in 6.2% of diet samples, and model estimates indicated that the Smallmouth Bass we captured consumed 925 larval lampreys in this 2-month study period. When extrapolated to a population estimate of Smallmouth Bass in this segment, we estimated 1,911 larval lampreys were consumed between July and September. Although the precision of these estimates was low, this magnitude of consumption suggests that Smallmouth Bass may negatively affect larval lamprey populations.

  1. Determination of dissolved inorganic species of iodine by spectrophotometric titration

    Energy Technology Data Exchange (ETDEWEB)

    Pesavento, Maria; Profumo, Antonella; Biesuz, Raffaela

    1987-09-01

    A method for determining iodate and iodine (+1) in aqueous solutions is proposed. The assay is similar to a previously described method for the determination of iodide and iodine (O), which were titrated with standard iodate in hydrochloric acid solution. A sample solution made 0.5-1.5 M in hydrochloric acid is titrated with a standard iodide solution and monitored spectrophotometrically at 230 nm. The species involved have strong absorbances that are well differentiated at this wavelength. By combining the two titrations it is possible to resolve any mixture of species of iodine in different oxidation states. The precision of the method (standard deviation) is the same both when determining a single species (IO/sub 3/-,I+,1/sub 2/ or I-) and a mixture, and is equal to 2 x 10/sup -7/ M. Chloride and bromide, even at very high concentrations, do not interfere.

  2. Determination of dissolved inorganic species of iodine by spectrophotometric titration

    International Nuclear Information System (INIS)

    Pesavento, Maria; Profumo, Antonella

    1987-01-01

    A method for determining iodate and iodine (+1) in aqueous solutions is proposed. The assay is similar to a previously described method for the determination of iodide and iodine (O), which were titrated with standard iodate in hydrochloric acid solution. A sample solution made 0.5-1.5 M in hydrochloric acid is titrated with a standard iodide solution and monitored spectrophotometrically at 230 nm. The species involved have strong absorbances that are well differentiated at this wavelength. By combining the two titrations it is possible to resolve any mixture of species of iodine in different oxidation states. The precision of the method (standard deviation) is the same both when determining a single species (IO 3 -,I+,1 2 or I-) and a mixture, and is equal to 2 x 10 -7 M. Chloride and bromide, even at very high concentrations, do not interfere. (author)

  3. Effects of sex pheromones and sexual maturation on locomotor activity in female sea lamprey (Petromyzon marinus)

    Science.gov (United States)

    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 reproductive synchrony of mature adults, thus increasing reproductive success in this species.

  4. Response of larval sea lampreys (Petromyzon marinus) to pulsed DC electrical stimuli in laboratory experiments

    Science.gov (United States)

    Bowen, Anjanette K.; Weisser, John W.; Bergstedt, Roger A.; Famoye, Felix

    2003-01-01

    Four electrical factors that are used in pulsed DC electrofishing for larval sea lampreys (Petromyzon marinus) were evaluated in two laboratory studies to determine the optimal values to induce larval emergence over a range of water temperatures and conductivities. Burrowed larvae were exposed to combinations of pulsed DC electrical factors including five pulse frequencies, three pulse patterns, and two levels of duty cycle over a range of seven voltage gradients in two separate studies conducted at water temperatures of 10, 15, and 20°C and water conductivities of 25, 200, and 900 μS/cm. A four-way analysis of variance was used to determine significant (α = 0.05) influences of each electrical factor on larval emergence. Multiple comparison tests with Bonferroni adjustments were used to determine which values of each factor resulted in significantly higher emergence at each temperature and conductivity. Voltage gradient and pulse frequency significantly affected emergence according to the ANOVA model at each temperature and conductivity tested. Duty cycle and pulse pattern generally did not significantly influence the model. Findings suggest that a setting of 2.0 V/cm, 3 pulses/sec, 10% duty, and 2:2 pulse pattern seems the most promising in waters of medium conductivity and across a variety of temperatures. This information provides a basis for understanding larval response to pulsed DC electrofishing gear factors and identifies electrofisher settings that show promise to increase the efficiency of the gear during assessments for burrowed sea lamprey larvae.

  5. cDNA sequences of two apolipoproteins from lamprey

    International Nuclear Information System (INIS)

    Pontes, M.; Xu, X.; Graham, D.; Riley, M.; Doolittle, R.F.

    1987-01-01

    The messages for two small but abundant apolipoproteins found in lamprey blood plasma were cloned with the aid of oligonucleotide probes based on amino-terminal sequences. In both cases, numerous clones were identified in a lamprey liver cDNA library, consistent with the great abundance of these proteins in lamprey blood. One of the cDNAs (LAL1) has a coding region of 105 amino acids that corresponds to a 21-residue signal peptide, a putative 8-residue propeptide, and the 76-residue mature protein found in blood. The other cDNA (LAL2) codes for a total of 191 residues, the first 23 of which constitute a signal peptide. The two proteins, which occur in the high-density lipoprotein fraction of ultracentrifuged plasma, have amino acid compositions similar to those of apolipoproteins found in mammalian blood; computer analysis indicates that the sequences are largely helix-permissive. When the sequences were searched against an amino acid sequence data base, rat apolipoprotein IV was the best matching candidate in both cases. Although a reasonable alignment can be made with that sequence and LAL1, definitive assignment of the two lamprey proteins to typical mammalian classes cannot be made at this point

  6. Development and Functional Organization of the Cranial Nerves in Lampreys.

    Science.gov (United States)

    Pombal, Manuel A; Megías, Manuel

    2018-04-16

    Lampreys, together with hagfishes, are the only extant representatives of the oldest branch of vertebrates, the agnathans, which are the sister group of gnathostomes; therefore, studies on these animals are of great evolutionary significance. Lampreys exhibit a particular life cycle with remarkable changes in their behavior, concomitant, in part, with important modifications in the head and its musculature, which might influence the development of the cranial nerves. In this context, some cranial nerves such as the optic nerve and the ocular motor nerves, which develop slowly during an extremely long larval period lasting more than five years, have been more thoroughly investigated; however, much less experimental information is available about others, such as the facial or the hypoglossal nerves. In addition, the possible existence of a "true" accessory nerve in these animals is still a matter of conjecture. Although growing in last decades, investigations on the physiology of the lamprey cranial nerves is scanty. This review focuses on past and recent findings that have contributed to characterize the anatomical organization of the cranial nerves in lampreys, including their components and nuclei, and their relations in the brain; in addition, comments on their development and functional role are also included. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

  7. Use of genotyping by sequencing data to develop a high-throughput and multifunctional SNP panel for conservation applications in Pacific lamprey.

    Science.gov (United States)

    Hess, Jon E; Campbell, Nathan R; Docker, Margaret F; Baker, Cyndi; Jackson, Aaron; Lampman, Ralph; McIlraith, Brian; Moser, Mary L; Statler, David P; Young, William P; Wildbill, Andrew J; Narum, Shawn R

    2015-01-01

    Next-generation sequencing data can be mined for highly informative single nucleotide polymorphisms (SNPs) to develop high-throughput genomic assays for nonmodel organisms. However, choosing a set of SNPs to address a variety of objectives can be difficult because SNPs are often not equally informative. We developed an optimal combination of 96 high-throughput SNP assays from a total of 4439 SNPs identified in a previous study of Pacific lamprey (Entosphenus tridentatus) and used them to address four disparate objectives: parentage analysis, species identification and characterization of neutral and adaptive variation. Nine of these SNPs are FST outliers, and five of these outliers are localized within genes and significantly associated with geography, run-timing and dwarf life history. Two of the 96 SNPs were diagnostic for two other lamprey species that were morphologically indistinguishable at early larval stages and were sympatric in the Pacific Northwest. The majority (85) of SNPs in the panel were highly informative for parentage analysis, that is, putatively neutral with high minor allele frequency across the species' range. Results from three case studies are presented to demonstrate the broad utility of this panel of SNP markers in this species. As Pacific lamprey populations are undergoing rapid decline, these SNPs provide an important resource to address critical uncertainties associated with the conservation and recovery of this imperiled species. © 2014 John Wiley & Sons Ltd.

  8. Determination of molecular species of lecithin from erythrocytes and plasma

    NARCIS (Netherlands)

    Golde, L.M.G. van; Tomasi, V.; Deenen, L.L.M. van

    The molecular species of lecithin from erythrocyte and plasma of man and rabbit were determined after conversion of the lecithins into diglycerides by means of hydrolysis with phospholipase C. The resultant diglycerides were separated by thin-layer chromatography on silica impregnated with silver

  9. Determining sample size for assessing species composition in ...

    African Journals Online (AJOL)

    Species composition is measured in grasslands for a variety of reasons. Commonly, observations are made using the wheel-point apparatus, but the problem of determining optimum sample size has not yet been satisfactorily resolved. In this study the wheel-point apparatus was used to record 2 000 observations in each of ...

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

    Science.gov (United States)

    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.

  11. Comparison of electrofishing techniques to detect larval lampreys in wadeable streams in the Pacific Northwest

    Science.gov (United States)

    Dunham, Jason B.; Chelgren, Nathan D.; Heck, Michael P.; Clark, Steven M.

    2013-01-01

    We evaluated the probability of detecting larval lampreys using different methods of backpack electrofishing in wadeable streams in the U.S. Pacific Northwest. Our primary objective was to compare capture of lampreys using electrofishing with standard settings for salmon and trout to settings specifically adapted for capture of lampreys. Field work consisted of removal sampling by means of backpack electrofishing in 19 sites in streams representing a broad range of conditions in the region. Captures of lampreys at these sites were analyzed with a modified removal-sampling model and Bayesian estimation to measure the relative odds of capture using the lamprey-specific settings compared with the standard salmonid settings. We found that the odds of capture were 2.66 (95% credible interval, 0.87–78.18) times greater for the lamprey-specific settings relative to standard salmonid settings. When estimates of capture probability were applied to estimating the probabilities of detection, we found high (>0.80) detectability when the actual number of lampreys in a site was greater than 10 individuals and effort was at least two passes of electrofishing, regardless of the settings used. Further work is needed to evaluate key assumptions in our approach, including the evaluation of individual-specific capture probabilities and population closure. For now our results suggest comparable results are possible for detection of lampreys by using backpack electrofishing with salmonid- or lamprey-specific settings.

  12. Contrasting extremes in water-related stresses determine species survival

    Science.gov (United States)

    Bartholomeus, R. P.; Witte, J. P. M.; van Bodegom, P. M.; van Dam, J. C.; Aerts, R.

    2012-04-01

    In temperate climates, soil moisture, in concert with nutrient availability and soil acidity, is the most important environmental filter in determining local plant species composition, as it determines the availability of both oxygen and water to plant roots. These resources are indispensable for meeting the physiological demands of plants. Especially the occurrence of both excessive dry and wet moisture conditions at a particular site has strong implications for the survival of species, because plants need traits that allow them to respond to such counteracting conditions. However, adapting to one stress may go at the cost of the other, i.e. there exists a trade-off in the tolerance for wet conditions and the tolerance for dry conditions. Until now, both large-scale (global) and plot-scale effects of soil moisture conditions on plant species composition have mostly been investigated through indirect environmental measures, which do not include the key soil physical and plant physiological processes in the soil-plant-atmosphere system. Moreover, researchers only determined effects of one of the water-related stresses, i.e. either oxygen or drought stress. In order to quantify both oxygen and drought stress with causal measures, we focused on interacting meteorological, soil physical, microbial, and plant physiological processes in the soil-plant-atmosphere system. We simulated these plant stresses with a novel, process-based approach, incorporating in detail the interacting processes in the soil-plant-atmosphere interface. High variability and extremes in resource availability can be highly detrimental to plant species ('you can only die once'). We show that co-occurrence of oxygen and drought stress reduces the percentage of specialists within a vegetation plot. The percentage of non-specialists within a vegetation plot, however, decreases significantly with increasing stress as long as only one of the stresses prevails, but increases significantly with an

  13. A nuclear DNA-based species determination and DNA quantification assay for common poultry species.

    Science.gov (United States)

    Ng, J; Satkoski, J; Premasuthan, A; Kanthaswamy, S

    2014-12-01

    DNA testing for food authentication and quality control requires sensitive species-specific quantification of nuclear DNA from complex and unknown biological sources. We have developed a multiplex assay based on TaqMan® real-time quantitative PCR (qPCR) for species-specific detection and quantification of chicken (Gallus gallus), duck (Anas platyrhynchos), and turkey (Meleagris gallopavo) nuclear DNA. The multiplex assay is able to accurately detect very low quantities of species-specific DNA from single or multispecies sample mixtures; its minimum effective quantification range is 5 to 50 pg of starting DNA material. In addition to its use in food fraudulence cases, we have validated the assay using simulated forensic sample conditions to demonstrate its utility in forensic investigations. Despite treatment with potent inhibitors such as hematin and humic acid, and degradation of template DNA by DNase, the assay was still able to robustly detect and quantify DNA from each of the three poultry species in mixed samples. The efficient species determination and accurate DNA quantification will help reduce fraudulent food labeling and facilitate downstream DNA analysis for genetic identification and traceability.

  14. Synthesis of juvenile lamprey migration and passage research and monitoring at Columbia and Snake River Dams

    Science.gov (United States)

    Mesa, Matthew G.; Weiland, Lisa K.; Christiansen, Helena E.

    2016-01-01

    We compiled and summarized previous sources of data and research results related to the presence, numbers, and migration timing characteristics of juvenile (eyed macropthalmia) and larval (ammocoetes) Pacific lamprey Entosphenus tridentatus, in the Columbia River basin (CRB). Included were data from various screw trap collections, data from historic fyke net studies, catch records of lampreys at JBS facilities, turbine cooling water strainer collections, and information on the occurrence of lampreys in the diets of avian and piscine predators. We identified key data gaps and uncertainties that should be addressed in a juvenile lamprey passage research program. The goal of this work was to summarize information from disparate sources so that managers can use it to prioritize and guide future research and monitoring efforts related to the downstream migration of juvenile Pacific lamprey within the CRB. A common finding in all datasets was the high level of variation observed for CRB lamprey in numbers present, timing and spatial distribution. This will make developing monitoring programs to accurately characterize lamprey migrations and passage more challenging. Primary data gaps centered around our uncertainty on the numbers of juvenile and larval present in the system which affects the ability to assign risk to passage conditions and prioritize management actions. Recommendations include developing standardized monitoring methods, such as at juvenile bypass systems (JBS’s), to better document numbers and timing of lamprey migrations at dams, and use biotelemetry tracking techniques to estimate survival potentials for different migration histories.

  15. Discovery of fossil lamprey larva from the Lower Cretaceous reveals its three-phased life cycle.

    Science.gov (United States)

    Chang, Mee-mann; Wu, Feixiang; Miao, Desui; Zhang, Jiangyong

    2014-10-28

    Lampreys are one of the two surviving jawless vertebrate groups and one of a few vertebrate groups with the best exemplified metamorphosis during their life cycle, which consists of a long-lasting larval stage, a peculiar metamorphosis, and a relatively short adulthood with a markedly different anatomy. Although the fossil records have revealed that many general features of extant lamprey adults were already formed by the Late Devonian (ca. 360 Ma), little is known about the life cycle of the fossil lampreys because of the lack of fossilized lamprey larvae or transformers. Here we report the first to our knowledge discovery of exceptionally preserved premetamorphic and metamorphosing larvae of the fossil lamprey Mesomyzon mengae from the Lower Cretaceous of Inner Mongolia, China. These fossil ammocoetes look surprisingly modern in having an eel-like body with tiny eyes, oral hood and lower lip, anteriorly positioned branchial region, and a continuous dorsal skin fin fold and in sharing a similar feeding habit, as judged from the detritus left in the gut. In contrast, the larger metamorphosing individuals have slightly enlarged eyes relative to large otic capsules, thickened oral hood or pointed snout, and discernable radials but still anteriorly extended branchial area and lack a suctorial oral disk, which characterize the early stages of the metamorphosis of extant lampreys. Our discovery not only documents the larval conditions of fossil lampreys but also indicates the three-phased life cycle in lampreys emerged essentially in their present mode no later than the Early Cretaceous.

  16. Determination of Biogenic Amines in Different Shrimp Species for Export

    International Nuclear Information System (INIS)

    Myat Myat Thaw; Oo Aung; Aung Myint; Bisswanger, Hans

    2004-06-01

    This study is part of the project on the ''Quality Assurance of Different Shrimp Species for Export''. Local shrimp samples were collected from Ministry of Livestock and Fisheries and various private enterprises. Contents of biogenic amines were determined by using benzoyl chloride derivatization method with HPLC (reverse phase high performance liquid chromatography). Based on the biogenic amines, quality index of shrimps were correlated with freshness index so that the grade of shrimp samples can be classified as excellent, good, and acceptable. All sizes of shrimps such as extra large, large, medium were found to excceptable respectively

  17. Determination of Tannins of Three Common Acacia Species of Sudan

    Directory of Open Access Journals (Sweden)

    Isam Eldin Hussein Elgailani

    2014-01-01

    Full Text Available The objective of this study is to analyze and compare tannins of three common Acacia species of Sudan, since vegetable tannins are important in leather industry. Acacia nilotica and Acacia seyal samples were collected from Sunt Forest in Khartoum State, while Acacia senegal samples were collected from the Debabat Forest in South Kordofan State. Bark samples from bulk collections of the three Acacia species were extracted with boiled deionized water. The amount of tannins present in these bulk samples was determined by Folin-Denis method for total phenolic materials, followed by precipitation with hide-powder. The difference between the amount of phenolic materials present before and after addition of hide-powder represents the amount of tannins present. The percentage of tannins in the leaves, bark, and mature and immature fruits of collections of individuals of Acacia species was estimated; mature and immature fruits of Acacia nilotica contain tannins (22.15% and 22.10%, resp.. The leaves of Acacia nilotica and Acacia seyal contain tannins (11.80% and 6.30%, resp.. The barks of Acacia seyal, Acacia nilotica, and Acacia senegal contain tannins (12.15%, 10.47%, and 3.49%, resp..

  18. Expression levels of parvalbumins determine allergenicity of fish species.

    Science.gov (United States)

    Griesmeier, U; Vázquez-Cortés, S; Bublin, M; Radauer, C; Ma, Y; Briza, P; Fernández-Rivas, M; Breiteneder, H

    2010-02-01

    Parvalbumins are the most important fish allergens. Polysensitization to various fish species is frequently reported and linked to the cross-reactivity of their parvalbumins. Studies on cross-reactivity and its association to the allergenicity of purified natural parvalbumins from different fish species are still lacking. In addition, some studies indicate that dark muscled fish such as tuna are less allergenic. Total protein extracts and purified parvalbumins from cod, whiff, and swordfish, all eaten frequently in Spain, were tested for their IgE-binding properties with 16 fish allergic patients' sera from Madrid. The extent of cross-reactivity of these parvalbumins was investigated by IgE ELISA inhibition assays. Additionally, the cDNA sequences of whiff and swordfish parvalbumins were determined. Extractable amounts of parvalbumins from cod were 20 times and from whiff 30 times higher than from swordfish. Parvalbumins were recognized by 94% of the patients in extracts of cod and whiff, but only by 60% in swordfish extracts. Nevertheless, a high cross-reactivity was determined for all purified parvalbumins by IgE inhibition. The amino acid sequence identities of the three parvalbumins were in a range of 62-74%. The parvalbumins of cod, whiff and swordfish are highly cross-reactive. The high amino acid sequence identity among cod, whiff and swordfish parvalbumins results in the observed IgE cross-reactivity. The low allergenicity of swordfish is due to the low expression levels of its parvalbumin.

  19. Traumatic injury induces changes in the expression of the serotonin 1A receptor in the spinal cord of lampreys.

    Science.gov (United States)

    Cornide-Petronio, María Eugenia; Fernández-López, Blanca; Barreiro-Iglesias, Antón; Rodicio, María Celina

    2014-02-01

    After spinal cord injury (SCI) in mammals, the loss of serotonin coming from the brainstem reduces the excitability of motor neurons and leads to a compensatory overexpression of serotonin receptors. Despite the key role of the serotonin receptor 1a in the control of locomotion, little attention has been put in the study of this receptor after SCI. In contrast to mammals, lampreys recover locomotion after a complete SCI, so, studies in this specie could help to understand events that lead to recovery of function. Here, we showed that in lampreys there is an acute increase in the expression of the serotonin 1A receptor transcript (5-ht1a) after SCI and a few weeks later expression levels go back to normal rostrally and caudally to the lesion. Overexpression of the 5-ht1a in rostral levels after SCI has not been reported in mammals, suggesting that this could be part of the plastic events that lead to the recovery of function in lampreys. The analysis of changes in 5-ht1a expression by zones (periventricular region and horizontally extended grey matter) showed that they followed the same pattern of changes detected in the spinal cord as a whole, with the exception of the caudal periventricular layer, where no significant differences were observed between control and experimental animals at any time post lesion. This suggests that different molecular signals act on the periventricular cells of the rostral and caudal regions to injury site and thus affecting their response to the injury in terms of expression of the 5-ht1a.

  20. Identification of Thrips Species on Garlic Fields in Hamedan Province and Determination of Dominant Species

    Directory of Open Access Journals (Sweden)

    Majid Mirab-balou

    2016-09-01

    Full Text Available Introduction: Garlic (Allium sativum (family Amaryllidaceae are one of important crops in Hamedan province. There are several insects and mites that by feeding on this plant cause to damage garlic yield. Among the insect pests, the most dangerous pests of garlic are thrips species (Insecta: Thysanoptera. In this group, onion thrips, Thrips tabaci Lindeman is widely distributed and is a dominant species. Its sap sucking causes tiny and silvery spots on the leaves that may spread all over the leaf surface with an unfavorable effect on yield production. In addition, imagoes and larvae living and feeding on this plant cause more serious damages. Due to serious damage of thrips in garlic fields of Hamedan province, it is necessary to identify thripsspecies for pest control programs. Materials and Methods: Thrips specimens were collected on leaves of garlic in Hamedan province (Maryanaj and Heydareh situated in the west of Iran, during 2012–2013. Herein, specimens were collected by shaking plants to white dish and specimens were kept in 70 % ethanol and transferred to the laboratory. All collected material was macerated in 5% KOH and subjected to dehydration in an ethanol series before being mounted onto glass slides. Subsequently, thrips specimens mounted onto slides in Hoyer’s medium form of the protocol given in Mirab-balou and Chen (2010. All descriptions, measurements and photos were made with a Leica DM IRB microscope, with a Leica Image 1000 system. Thrips specimens were identified by author in species level. Specimens are deposited in the collection of Department of Plant Protection, College of Agriculture, Ilam University, Iran (ILAMU. In addition, dominant thrips species were also determined. For this purpose, regular samplings were done in fields of two regions of Hamedan province every two weeks, and totally, 2040 specimens (adult were collected. Results and Discussion: The world fauna of Thysanoptera, are presently known to be

  1. The stock of invasive insect species and its economic determinants.

    Science.gov (United States)

    Hlasny, Vladimir

    2011-06-01

    Invasions of nonindigenous organisms have long been linked to trade, but the contribution of individual trade pathways remains poorly understood, because species are not observed immediately upon arrival and the number of species arriving annually is unknown. Species interception records may count both new arrivals and species long introduced. Furthermore, the stock of invasive insect species already present is unknown. In this study, a state-space model is used to infer the stock of detected as well as undetected invasive insect species established in the United States. A system of equations is estimated jointly to distinguish the patterns of introduction, identification, and eradication. Introductions of invasive species are modeled as dependent on the volume of trade and arrival of people. Identifications depend on the public efforts at invasive species research, as well as on the established stock of invasive species that remain undetected. Eradications of both detected and undetected invasive species depend on containment and quarantine efforts, as well as on the stock of all established invasive species. These patterns are estimated by fitting the predicted number of invasive species detections to the observed record in the North American Non-Indigenous Arthropod Database. The results indicate that agricultural imports are the most important pathway of introduction, followed by immigration of people. Expenditures by the U.S. Department of Agriculture and the Agricultural Research Service are found to explain the species identification record well. Between three and 38 invasive insect species are estimated to be established in the United States undetected.

  2. Effectiveness of common fish screen materials for protecting lamprey ammocoetes—Influence of sweeping velocities and decreasing flows

    Science.gov (United States)

    Mesa, Matthew G.; Liedtke, Theresa L.; Weiland, Lisa K.; Christiansen, Helena E.

    2017-12-14

    In previous tests of the effectiveness of four common fish screen materials for excluding lamprey ammocoetes, we determined that woven wire (WW) allowed substantially more entrainment than perforated plate (PP), profile bar (PB), or Intralox (IL) material. These tests were simplistic because they used small vertically-oriented screens positioned perpendicular to the flow without a bypass or a sweeping velocity (SV). In the subsequent test discussed in this report, we exposed ammocoetes to much larger (2.5-m-wide) screen panels with flows up to 10 ft3 /s, a SV component, and a simulated bypass channel. The addition of a SV modestly improved protection of lamprey ammocoetes for all materials tested. A SV of 35 cm/s with an approach velocity (AV) of 12 cm/s, was able to provide protection for fish about 5–15 mm smaller than the protection provided by an AV of 12 cm/s without a SV component. The best-performing screen panels (PP, IL, and PB) provided nearly complete protection from entrainment for fish greater than 50-mm toal length, but the larger openings in the WW material only protected fish greater than 100-mm total length. Decreasing the AV and SV by 50 percent expanded the size range of protected lampreys by about 10–15 mm for those exposed to IL and WW screens, and it decreased the protective ability of PP screens by about 10 mm. Much of the improvement for IL and WW screens under the reduced flow conditions resulted from an increase in the number of lampreys swimming away from the screen. Fish of all sizes became impinged (that is, stuck on the screen surface for more than 1 s) on the screens, with the rate of impingement highest on PP (39– 72 percent) and lowest on WW (7–22 percent). Although impingements were common, injuries were rare, and 24-h post-test survival was greater than 99 percent. Our results refined the level of protection provided by these screen materials when both an AV and SV are present and confirmed our earlier recommendation that

  3. 78 FR 48943 - Endangered and Threatened Wildlife and Plants; Endangered Species Act Listing Determination for...

    Science.gov (United States)

    2013-08-12

    ... Atmospheric Administration Endangered and Threatened Wildlife and Plants; Endangered Species Act Listing...; Endangered Species Act Listing Determination for Alewife and Blueback Herring AGENCY: National Marine... (Alosa aestivalis) as threatened under the Endangered Species Act (ESA) throughout all or a significant...

  4. Characterization of Sea Lamprey stream entry using dual‐frequency identification sonar

    Science.gov (United States)

    McCain, Erin L.; Johnson, Nicholas; Hrodey, Peter J.; Pangle, Kevin L.

    2018-01-01

    Effective methods to control invasive Sea Lampreys Petromyzon marinus in the Laurentian Great Lakes often rely on knowledge of the timing of the Sea Lamprey spawning migration, which has previously been characterized using data gathered from traps. Most assessment traps are located many kilometers upstream from the river mouth, so less is known about when Sea Lampreys enter spawning streams and which environmental cues trigger their transition from lakes to rivers. To decide how to develop barriers and traps that target Sea Lampreys when they enter a stream, the stream entry of Sea Lampreys into a Lake Huron tributary during 2 years was assessed using dual‐frequency identification sonar (DIDSON). Sea Lampreys entered the stream in low densities when temperatures first reached 4°C, which was up to 6 weeks and a mean of 4 weeks earlier than when they were first captured in traps located upstream. The probability of stream entry was significantly affected by stream temperature and discharge, and stream entry timing peaked when stream temperatures rose to 12°C and discharge was high. Examination of the entry at a finer temporal resolution (i.e., minutes) indicated that Sea Lampreys did not exhibit social behavior (e.g., shoaling) during stream entry. Our findings indicate that Sea Lampreys may be vulnerable to alternative trap types near river mouths and hydraulic challenges associated with traditional traps. Also, seasonal migration barriers near stream mouths may need to be installed soon after ice‐out to effectively block the entire adult Sea Lamprey cohort from upstream spawning habitat.

  5. Habituation of adult sea lamprey repeatedly exposed to damage-released alarm and predator cues

    Science.gov (United States)

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

    2016-01-01

    Predation is an unforgiving selective pressure affecting the life history, morphology and behaviour of prey organisms. Selection should favour organisms that have the ability to correctly assess the information content of alarm cues. This study investigated whether adult sea lamprey Petromyzon marinus habituate to conspecific damage-released alarm cues (fresh and decayed sea lamprey extract), a heterospecific damage-released alarm cue (white sucker Catostomus commersoniiextract), predator cues (Northern water snake Nerodia sipedon washing, human saliva and 2-phenylethylamine hydrochloride (PEA HCl)) and a conspecific damage-released alarm cue and predator cue combination (fresh sea lamprey extract and human saliva) after they were pre-exposed 4 times or 8 times, respectively, to a given stimulus the previous night. Consistent with our prediction, adult sea lamprey maintained an avoidance response to conspecific damage-released alarm cues (fresh and decayed sea lamprey extract), a predator cue presented at high relative concentration (PEA HCl) and a conspecific damage-released alarm cue and predator cue combination (fresh sea lamprey extract plus human saliva), irrespective of previous exposure level. As expected, adult sea lamprey habituated to a sympatric heterospecific damage-released alarm cue (white sucker extract) and a predator cue presented at lower relative concentration (human saliva). Adult sea lamprey did not show any avoidance of the Northern water snake washing and the Amazon sailfin catfish extract (heterospecific control). This study suggests that conspecific damage-released alarm cues and PEA HCl present the best options as natural repellents in an integrated management program aimed at controlling the abundance of sea lamprey in the Laurentian Great Lakes.

  6. The determination of the number of light neutrino species

    International Nuclear Information System (INIS)

    Rademakers, A.A.

    1991-01-01

    The hadronic decays of the Z 0 boson in e + e - collisions have been studied with the DELPHI detector at LEP at ten different center-of-mass energies around the Z 0 peak. The total in integrated luminosity, in 1989, was 573nb -1 . The Z 0 resonance line-shape has been measured using about 11000 selected hadronic events. The selection efficiency was (92.0 ± 1.1)% and the uncertainty on the luminosity measurement was estimated to be 2.4%. The normalized hadronic cross sections were fitted to the model independent formula by Borelli et al. to obtain the Z 0 mass and width, the Born peak cross section and the number of light neutrino species. from the analysis of leptonic events the ratio of hadronic over leptonic partial widths was obtained. Using this ratio and assuming lepton universality the hadronic and leptonic partial widths as well as the sum of the partial widths of invisible Z 0 decays could be determined. The results are in good agreement with the Standard Model with a large top-quark mass. They also agree very well with the measurements of the other LEP experiments. (author). 59 refs.; 43 figs.; 15 tabs

  7. Thyroid hormone deiodinase type 2 mRNA levels in sea lamprey (Petromyzon marinus) are regulated during metamorphosis and in response to a thyroid challenge.

    Science.gov (United States)

    Stilborn, S Salina M; Manzon, Lori A; Schauenberg, Jennifer D; Manzon, Richard G

    2013-03-01

    Thyroid hormones (THs) are crucial for normal vertebrate development and are the one obligate morphogen that drives amphibian metamorphosis. However, contrary to other metamorphosing vertebrates, lampreys exhibit a sharp drop in serum TH early in metamorphosis, and anti-thyroid agents such as potassium perchlorate (KClO(4)) induce metamorphosis. The type 2 deiodinase (D2) enzyme is a key regulator of TH availability during amphibian metamorphosis. We set out to determine how D2 may be involved in the regulation of lamprey metamorphosis and thyroid homeostasis. We cloned a 1.8Kb Petromyzon marinus D2 cDNA that includes the entire protein coding region and a selenocysteine (Sec) codon. Northern blotting indicated that the lamprey D2 mRNA is the longest reported to date (>9Kb). Using real-time PCR, we showed that intestinal and hepatic D2 mRNA levels were elevated prior to and during the early stages of metamorphosis and then declined dramatically to low levels that were sustained for the remainder of metamorphosis. These data are consistent with previously reported changes in serum TH levels and deiodinase activity. Treatment of larvae with either TH or KClO(4) significantly affected D2 mRNA levels in the intestine and liver. These D2 mRNA levels during metamorphosis and in response to thyroid challenges suggest that D2 may function in the regulation of TH levels during lamprey metamorphosis and the maintenance of TH homeostasis. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. A pheromone outweighs temperature in influencing migration of sea lamprey

    Science.gov (United States)

    Brant, Cory O.; Li, Ke; Johnson, Nicholas S.; Li, Weiming

    2015-01-01

    Organisms continuously acquire and process information from surrounding cues. While some cues complement one another in delivering more reliable information, others may provide conflicting information. How organisms extract and use reliable information from a multitude of cues is largely unknown. We examined movement decisions of sea lampreys (Petromyzon marinus L.) exposed to a conspecific and an environmental cue during pre-spawning migration. Specifically, we predicted that the mature male-released sex pheromone 3-keto petromyzonol sulfate (3kPZS) will outweigh the locomotor inhibiting effects of cold stream temperature (less than 15°C). Using large-scale stream bioassays, we found that 3kPZS elicits an increase (more than 40%) in upstream movement of pre-spawning lampreys when the water temperatures were below 15°C. Both warming temperatures and conspecific cues increase upstream movement when the water temperature rose above 15°C. These patterns define an interaction between abiotic and conspecific cues in modulating animal decision-making, providing an example of the hierarchy of contradictory information.

  9. A thermogenic secondary sexual character in male sea lamprey

    Science.gov (United States)

    Chung-Davidson, Yu-Wen; Priess, M. Cody; Yeh, Chu-Yin; Brant, Cory O.; Johnson, Nicholas S.; Li, Ke; Nanlohy, Kaben G.; Bryan, Mara B.; Brown, C. Titus; Choi, Jongeun; Li, Weiming

    2013-01-01

    Secondary sexual characters in animals are exaggerated ornaments or weapons for intrasexual competition. Unexpectedly, we found that a male secondary sexual character in sea lamprey (Petromyzon marinus ) is a thermogenic adipose tissue that instantly increases its heat production during sexual encounters. This secondary sexual character, developed in front of the anterior dorsal fin of mature males, is a swollen dorsal ridge known as the ‘rope’ tissue. It contains nerve bundles, multivacuolar adipocytes and interstitial cells packed with small lipid droplets and mitochondria with dense and highly organized cristae. The fatty acid composition of the rope tissue is rich in unsaturated fatty acids. The cytochrome c oxidase activity is high but the ATP concentration is very low in the mitochondria of the rope tissue compared with those of the gill and muscle tissues. The rope tissue temperature immediately rose up to 0.3°C when the male encountered a conspecific. Mature males generated more heat in the rope and muscle tissues when presented with a mature female than when presented with a male (paired t-test, P-3 more heat than the muscle in 10 min. Transcriptome analyses revealed that genes involved in fat cell differentiation are upregulated whereas those involved in oxidative-phosphorylation-coupled ATP synthesis are downregulated in the rope tissue compared with the gill and muscle tissues. Sexually mature male sea lamprey possess the only known thermogenic secondary sexual character that shows differential heat generation toward individual conspecifics.

  10. Cuticular hydrocarbons for species determination of tropical termites

    Science.gov (United States)

    Michael I. Haverty; Lori J. Nelson; Barbara L. Thorne; Margaret S. Collins; Johanna P.E.C. Darlington; Marion Page

    1992-01-01

    Cuticular hydrocarbons can be used to discriminate species in Coptotermes and Nasutitermes, here discussed for selected species from locations in the Pacific Rim and several Caribbean islands. We recently reexamined the cuticular hydrocarbons of Coptotermes formosanus and identified several dimethylalkanes that...

  11. Dispersal ability determines the scaling properties of species abundance distributions

    DEFF Research Database (Denmark)

    Borda-De-Água, Luís; Whittaker, Robert James; Cardoso, Pedro

    2017-01-01

    with computer simulations, low dispersal ability species generate a hump for intermediate abundance classes earlier than the distributions of high dispersal ability species. Importantly, when plotted as function of sample size, the raw moments of the SADs of arthropods have a power law pattern similar...

  12. Bioinformatic Characterization of Genes and Proteins Involved in Blood Clotting in Lampreys

    OpenAIRE

    Doolittle, RF

    2015-01-01

    © 2015, Springer Science+Business Media New York. Lampreys and hagfish are the earliest diverging of extant vertebrates and are obvious targets for investigating the origins of complex biochemical systems found in mammals. Currently, the simplest approach for such inquiries is to search for the presence of relevant genes in whole genome sequence (WGS) assemblies. Unhappily, in the past a high-quality complete genome sequence has not been available for either lampreys or hagfish, precluding th...

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

    Science.gov (United States)

    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.

  14. Low reproductive isolation and highly variable levels of gene flow reveal limited progress towards speciation between European river and brook lampreys.

    Science.gov (United States)

    Rougemont, Q; Gaigher, A; Lasne, E; Côte, J; Coke, M; Besnard, A-L; Launey, S; Evanno, G

    2015-12-01

    Ecologically based divergent selection is a factor that could drive reproductive isolation even in the presence of gene flow. Population pairs arrayed along a continuum of divergence provide a good opportunity to address this issue. Here, we used a combination of mating trials, experimental crosses and population genetic analyses to investigate the evolution of reproductive isolation between two closely related species of lampreys with distinct life histories. We used microsatellite markers to genotype over 1000 individuals of the migratory parasitic river lamprey (Lampetra fluviatilis) and freshwater-resident nonparasitic brook lamprey (Lampetra planeri) distributed in 10 sympatric and parapatric population pairs in France. Mating trials, parentage analyses and artificial fertilizations demonstrated a low level of reproductive isolation between species even though size-assortative mating may contribute to isolation. Most parapatric population pairs were strongly differentiated due to the joint effects of geographic distance and barriers to migration. In contrast, we found variable levels of gene flow between sympatric populations ranging from panmixia to moderate differentiation, which indicates a gradient of divergence with some population pairs that may correspond to alternative morphs or ecotypes of a single species and others that remain partially isolated. Ecologically based divergent selection may explain these variable levels of divergence among sympatric population pairs, but incomplete genome swamping following secondary contact could have also played a role. Overall, this study illustrates how highly differentiated phenotypes can be maintained despite high levels of gene flow that limit the progress towards speciation. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

  15. Species composition of a soil invertebrate multi-species test system determines the level of ecotoxicity

    DEFF Research Database (Denmark)

    Sechi, Valentina; D'Annibale, Alessandra; Maraldo, Kristine

    2014-01-01

    A soil multi-species, SMS, experimental test system consisting of the natural microbial community, five collembolan species and a predatory mite along with either Enchytraeus crypticus or the earthworm Eisenia fetida were exposed to α-cypermethrin. A comparison of the performance of these two typ...

  16. Genetic determinants of antifungal resistance in Candida species ...

    African Journals Online (AJOL)

    In the previous decades, it has been an increase in cases of resistance to antifungal agents used in the prophylaxis and treatment of infections caused by Candida species. The emergence of resistance to drug classes, it is usually explained by genome alterations ranging from point mutations to gain or loss of whole ...

  17. Determinants of orchid species diversity in Latin America

    Czech Academy of Sciences Publication Activity Database

    Štípková, Zuzana; Traxmandlová, Iva; Kindlmann, Pavel

    2016-01-01

    Roč. 16, č. 2 (2016), s. 293-297 ISSN 1409-3871 R&D Projects: GA MŠk(CZ) LO1415; GA ČR GB14-36098G Institutional support: RVO:67179843 Keywords : altitude * habitat diversity * species-area relationship Subject RIV: EF - Botanics

  18. Luminometric determination of antioxidant capacity towards individual reactive oxygen species

    Czech Academy of Sciences Publication Activity Database

    Komrsková, D.; Lojek, Antonín; Hrbáč, J.; Číž, Milan

    2005-01-01

    Roč. 3, č. 1 (2005), S25 [Cells VI - Biological Days /18./. 24.10.2005-26.10.2005, České Budějovice] R&D Projects: GA ČR(CZ) GA524/01/1219 Institutional research plan: CEZ:AV0Z50040507 Keywords : chemiluminescence * reactive oxygen species * scavenger Subject RIV: BO - Biophysics

  19. COMPLEMENTARY APPROACHES TO THE DETERMINATION OF ARSENIC SPECIES RELEVANT TO CONCENTRATED ANIMAL FEEDING OPERATIONS

    Science.gov (United States)

    Ion-exchange chromatography is the most often used analytical approach for arsenicspeciation, due to the weak-acid nature of several of its species. However, no singletechnique can determine all potentially occurring arsenic species, especially in complexe...

  20. Species composition of a soil invertebrate multi-species test system determines the level of ecotoxicity

    International Nuclear Information System (INIS)

    Sechi, Valentina; D'Annibale, Alessandra; Maraldo, Kristine; Johansen, Anders; Bossi, Rossana; Jensen, John; Krogh, Paul Henning

    2014-01-01

    A soil multi-species, SMS, experimental test system consisting of the natural microbial community, five collembolan species and a predatory mite along with either Enchytraeus crypticus or the earthworm Eisenia fetida were exposed to α-cypermethrin. A comparison of the performance of these two types of SMSs is given to aid the development of a standard test system. E. fetida had a positive effect on the majority of the species, reducing the negative insecticide effect. E. fetida affected the species sensitivity and decreased the degradation of the insecticide due to the organic matter incorporation of earthworm food. After 8 weeks, the EC50 was 0.76 mg kg −1 for enchytraeids and ranged between 2.7 and 18.9 mg kg −1 for collembolans, more sensitive than previously observed with single species. Changes observed in the community structure and function illustrates the strength of a multi-species test system as an ecotoxicological tool compared to single species tests. -- Highlights: • Degradation of alpha-cypermethrin was faster with enchytraeids than with earthworms. • Lumbricid castings and bioturbation explains bioavailability of α-cypermethrin. • Pesticide effects on soil arthropods alter with the community composition. • Multispecies test systems are feasible with either an enchytraeid or a lumbricid. • Collembolans are more sensitive to cypermethrin with enchytraeids than with earthworms. -- Soil ecotoxicological fate and effects in multispecies test systems are affected by earthworm activity

  1. Minimizing opportunity costs to aquatic connectivity restoration while controlling an invasive species.

    Science.gov (United States)

    Milt, Austin W; Diebel, Matthew W; Doran, Patrick J; Ferris, Michael C; Herbert, Matthew; Khoury, Mary L; Moody, Allison T; Neeson, Thomas M; Ross, Jared; Treska, Ted; O'Hanley, Jesse R; Walter, Lisa; Wangen, Steven R; Yacobson, Eugene; McIntyre, Peter B

    2018-03-08

    Controlling invasive species is critical for conservation but can have unintended consequences for native species and divert resources away from other efforts. This dilemma occurs on a grand scale in the North American Great Lakes, where dams and culverts block tributary access to habitat of desirable fish species and are a lynchpin of long-standing efforts to limit ecological damage inflicted by the invasive, parasitic sea lamprey (Petromyzon marinus). Habitat restoration and sea-lamprey control create conflicting goals for managing aging infrastructure. We used optimization to minimize opportunity costs of habitat gains for 37 desirable migratory fishes that arose from restricting sea lamprey access (0-25% increase) when selecting barriers for removal under a limited budget (US$1-105 million). Imposing limits on sea lamprey habitat reduced gains in tributary access for desirable species by 15-50% relative to an unconstrained scenario. Additional investment to offset the effect of limiting sea-lamprey access resulted in high opportunity costs for 30 of 37 species (e.g., an additional US$20-80 million for lake sturgeon [Acipenser fulvescens]) and often required ≥5% increase in sea-lamprey access to identify barrier-removal solutions adhering to the budget and limiting access. Narrowly distributed species exhibited the highest opportunity costs but benefited more at less cost when small increases in sea-lamprey access were allowed. Our results illustrate the value of optimization in limiting opportunity costs when balancing invasion control against restoration benefits for diverse desirable species. Such trade-off analyses are essential to the restoration of connectivity within fragmented rivers without unleashing invaders. © 2018 Society for Conservation Biology.

  2. Gene expression during ovarian differentiation in parasitic and non-parasitic lampreys: implications for fecundity and life history types.

    Science.gov (United States)

    Spice, Erin K; Whyard, Steven; Docker, Margaret F

    2014-11-01

    Lampreys diverged from the jawed vertebrate lineage approximately 500million years ago. Lampreys undergo sex differentiation much later than most other vertebrates, and ovarian differentiation occurs several years before testicular differentiation. The genetic basis of lamprey sex differentiation is of particular interest both because of the phylogenetic importance of lampreys and because of their unusual pattern of sex differentiation. As well, differences between parasitic and non-parasitic lampreys may first become evident at ovarian differentiation. However, nothing is known about the genetic basis of ovarian differentiation in lampreys. This study examined potential differences in gene expression before, during, and after ovarian differentiation in parasitic chestnut lamprey Ichthyomyzon castaneus and non-parasitic northern brook lamprey Ichthyomyzonfossor. Eight target genes (17β-hydroxysteroid dehydrogenase, germ cell-less, estrogen receptor β, insulin-like growth factor 1 receptor, daz-associated protein 1, cytochrome c oxidase subunit III, Wilms' tumour suppressor protein 1, and dehydrocholesterol reductase 7) were examined. Northern brook lamprey displayed higher expression of cytochrome c oxidase subunit III, whereas chestnut lamprey displayed higher expression of insulin-like growth factor 1 receptor; these genes may be involved in apoptosis and oocyte growth, respectively. Presumptive male larvae had higher expression of Wilms' tumour suppressor protein 1, which may be involved in the undifferentiated gonad and/or later testicular development. Differentiated females had higher expression of 17β hydroxysteroid dehydrogenase and daz-associated protein 1, which may be involved in female development. This study is the first to identify genes that may be involved in ovarian differentiation and fecundity in lampreys. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Determinants of orchid species diversity in world islands

    Czech Academy of Sciences Publication Activity Database

    Traxmandlová, Iva; Ackerman, J. D.; Tremblay, R. L.; Roberts, D.L.; Štípková, Zuzana; Kindlmann, Pavel

    2018-01-01

    Roč. 217, č. 1 (2018), s. 12-15 ISSN 0028-646X R&D Projects: GA MŠk(CZ) LO1415; GA ČR GB14-36098G Institutional support: RVO:86652079 Keywords : habitat diversity * island biogeography * latitude * Orchidaceae * species richness * species–area relationship Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 7.330, year: 2016

  4. A simple, cost-effective emitter for controlled release of fish pheromones: development, testing, and application to management of the invasive sea lamprey

    Science.gov (United States)

    Wagner, Michael C.; Hanson, James E.; Meckley, Trevor D.; Johnson, Nicholas; Bals, Jason D.

    2018-01-01

    Semiochemicals that elicit species-specific attraction or repulsion have proven useful in the management of terrestrial pests and hold considerable promise for control of nuisance aquatic species, particularly invasive fishes. Because aquatic ecosystems are typically large and open, use of a semiochemical to control a spatially dispersed invader will require the development of a cost-effective emitter that is easy to produce, environmentally benign, inexpensive, and controls the release of the semiochemical without altering its structure. We examined the release properties of five polymers, and chose polyethylene glycol (PEG) as the best alternative. In a series of laboratory and field experiments, we examined the response of the invasive sea lamprey to PEG, and to a partial sex pheromone emitted from PEG that has proven effective as a trap bait to capture migrating sea lamprey prior to spawning. Our findings confirm that the sea lamprey does not behaviorally respond to PEG, and that the attractant response to the pheromone component was conserved when emitted from PEG. Further, we deployed the pheromone-PEG emitters as trap bait during typical control operations in three Great Lakes tributaries, observing similar improvements in trap performance when compared to a previous study using mechanically pumped liquid pheromone. Finally, the polymer emitters tended to dissolve unevenly in high flow conditions. We demonstrate that housing the emitter stabilizes the dissolution rate at high water velocity. We conclude the performance characteristics of PEG emitters to achieve controlled-release of a semiochemical are sufficient to recommend its use in conservation and management activities related to native and invasive aquatic organisms.

  5. Evidence for a receiver bias underlying female preference for a male mating pheromone in sea lamprey

    Science.gov (United States)

    Buchinger, Tyler J.; Wang, Huiyong; Li, Weiming; Johnson, Nicholas S.

    2013-01-01

    Receiver bias models suggest that a male sexual signal became exaggerated to match a pre-existing sensory, perceptual or cognitive disposition of the female. Accordingly, these models predict that females of related taxa possessing the ancestral state of signalling evolved preference for the male trait in a non-sexual context. We postulated that female preference for the male-released bile alcohol mating pheromone, 3 keto petromyzonol sulfate (3kPZS), of the sea lamprey (Petromyzon marinus) evolved as a result of a receiver bias. In particular, we propose that migratory silver lamprey (Ichthyomyzon unicuspis), a basal member of the Petromyzontidae, evolved a preference for 3kPZS released by stream-resident larvae as a means of identifying productive habitat for offspring. Larval silver lamprey released 3kPZS at rates sufficient to be detected by migratory lampreys. Females responded to 3kPZS by exhibiting upstream movement behaviours relevant in a migratory context, but did not exhibit proximate behaviours important to mate search and spawning. Male silver lamprey did not release 3kPZS at rates sufficient to be detected by females in natural high-volume stream environments. We infer that female silver lamprey cue onto 3kPZS excreted by stream-resident larvae as a mechanism to locate habitat conducive to offspring survival and that males do not signal with 3kPZS. We suggest that this female preference for a male signal in a non-sexual context represents a bias leading to the sexual signalling observed in sea lamprey.

  6. 76 FR 31556 - Endangered and Threatened Wildlife and Plants; Endangered Species Act Listing Determination for...

    Science.gov (United States)

    2011-06-01

    ... Atlantic bluefin tuna (Thunnus thynnus) as threatened or endangered under the Endangered Species Act (ESA... Species Act Listing Determination for Atlantic Bluefin Tuna AGENCY: National Marine Fisheries Service... endangered species within the foreseeable future throughout all or a significant portion of its range.'' The...

  7. Asymptotic size determines species abundance in the marine size spectrum

    DEFF Research Database (Denmark)

    Andersen, Ken Haste; Beyer, Jan

    2006-01-01

    The majority of higher organisms in the marine environment display indeterminate growth; that is, they continue to grow throughout their life, limited by an asymptotic size. We derive the abundance of species as a function of their asymptotic size. The derivation is based on size-spectrum theory......, where population structure is derived from physiology and simple arguments regarding the predator-prey interaction. Using a hypothesis of constant satiation, which states that the average degree of satiation is independent of the size of an organism, the number of individuals with a given size is found...... to be proportional to the weight raised to the power -2.05, independent of the predator/prey size ratio. This is the first time the spectrum exponent has been derived solely on the basis of processes at the individual level. The theory furthermore predicts that the parameters in the von Bertalanffy growth function...

  8. Postglacial migration supplements climate in determining plant species ranges in Europe

    Science.gov (United States)

    Normand, Signe; Ricklefs, Robert E.; Skov, Flemming; Bladt, Jesper; Tackenberg, Oliver; Svenning, Jens-Christian

    2011-01-01

    The influence of dispersal limitation on species ranges remains controversial. Considering the dramatic impacts of the last glaciation in Europe, species might not have tracked climate changes through time and, as a consequence, their present-day ranges might be in disequilibrium with current climate. For 1016 European plant species, we assessed the relative importance of current climate and limited postglacial migration in determining species ranges using regression modelling and explanatory variables representing climate, and a novel species-specific hind-casting-based measure of accessibility to postglacial colonization. Climate was important for all species, while postglacial colonization also constrained the ranges of more than 50 per cent of the species. On average, climate explained five times more variation in species ranges than accessibility, but accessibility was the strongest determinant for one-sixth of the species. Accessibility was particularly important for species with limited long-distance dispersal ability, with southern glacial ranges, seed plants compared with ferns, and small-range species in southern Europe. In addition, accessibility explained one-third of the variation in species' disequilibrium with climate as measured by the realized/potential range size ratio computed with niche modelling. In conclusion, we show that although climate is the dominant broad-scale determinant of European plant species ranges, constrained dispersal plays an important supplementary role. PMID:21543356

  9. Temporal genetic population structure and interannual variation in migration behavior of Pacific Lamprey Entosphenus tridentatus

    Science.gov (United States)

    Clemens, Benjamin J.; Wyss, Lance A.; McCoun, Rebecca; Courter, Ian; Schwabe, Lawrence; Peery, Christopher; Schreck, Carl B.; Spice, Erin K.; Docker, Margaret F.

    2017-01-01

    Studies using neutral loci suggest that Pacific lamprey, Entosphenus tridentatus, lack strong spatial genetic population structure. However, it is unknown whether temporal genetic population structure exists. We tested whether adult Pacific lamprey: (1) show temporal genetic population structure; and (2) migrate different distances between years. We non-lethally sampled lamprey for DNA in 2009 and 2010 and used eight microsatellite loci to test for genetic population structure. We used telemetry to record the migration behaviors of these fish. Lamprey were assignable to three moderately differentiated genetic clusters (FST = 0.16–0.24 for all pairwise comparisons): one cluster was composed of individuals from 2009, and the other two contained individuals from 2010. The FST value between years was 0.13 and between genetic clusters within 2010 was 0.20. A total of 372 (72.5%) fish were detected multiple times during their migrations. Most fish (69.9%) remained in the mainstem Willamette River; the remaining 30.1% migrated into tributaries. Eighty-two lamprey exhibited multiple back-and-forth movements among tributaries and the mainstem, which may indicate searching behaviors. All migration distances were significantly greater in 2010, when the amplitude of river discharge was greater. Our data suggest genetic structuring between and within years that may reflect different cohorts.

  10. Prosomeric map of the lamprey forebrain based on calretinin immunocytochemistry, Nissl stain, and ancillary markers.

    Science.gov (United States)

    Pombal, M A; Puelles, L

    1999-11-22

    The structural organization of the lamprey extratelencephalic forebrain is re-examined from the perspective of the prosomeric segmental paradigm. The question asked was whether the prosomeric forebrain model used for gnathostomes is of material advantage for interpreting subdivisions in the lamprey forebrain. To this aim, the main longitudinal and transverse landmarks recognized by the prosomeric model in other vertebrates were identified in Nissl-stained lamprey material. Lines of cytoarchitectural discontinuity and contours of migrated neuronal groups were mapped in a two-dimensional sagittal representation and were also classified according to their radial position. Immunocytochemical mapping of calretinin expression in adjacent sections served to define particular structural units better, in particular, the dorsal thalamus. These data were complemented by numerous other chemoarchitectonic observations obtained with ancillary markers, which identified additional specific formations, subdivisions, or boundaries. Emphasis was placed on studying whether such chemically defined neuronal groups showed boundaries aligned with the postulated inter- or intraprosomeric boundaries. The course of diverse axonal tracts was studied also with regard to their prosomeric topography. This analysis showed that the full prosomeric model applies straightforwardly to the lamprey forebrain. This finding implies that a common segmental and longitudinal organization of the neural tube may be primitive for all vertebrates. Interesting novel aspects appear in the interpretation of the lamprey pretectum, the dorsal and ventral thalami, and the hypothalamus. The topologic continuity of the prosomeric forebrain regions with evaginated or non-evaginated portions of the telencephalon was also examined. Copyright 1999 Wiley-Liss, Inc.

  11. A new clarification method to visualize biliary degeneration during liver metamorphosis in sea lamprey (Petromyzon marinus)

    Science.gov (United States)

    Chung-Davidson, Yu-Wen; Davidson, Peter J.; Scott, Anne M.; Walaszczyk, Erin J.; Brant, Cory O.; Buchinger, Tyler; Johnson, Nicholas S.; Li, Weiming

    2014-01-01

    Biliary atresia is a rare disease of infancy, with an estimated 1 in 15,000 frequency in the southeast United States, but more common in East Asian countries, with a reported frequency of 1 in 5,000 in Taiwan. Although much is known about the management of biliary atresia, its pathogenesis is still elusive. The sea lamprey (Petromyzon marinus) provides a unique opportunity to examine the mechanism and progression of biliary degeneration. Sea lamprey develop through three distinct life stages: larval, parasitic, and adult. During the transition from larvae to parasitic juvenile, sea lamprey undergo metamorphosis with dramatic reorganization and remodeling in external morphology and internal organs. In the liver, the entire biliary system is lost, including the gall bladder and the biliary tree. A newly-developed method called “CLARITY” was modified to clarify the entire liver and the junction with the intestine in metamorphic sea lamprey. The process of biliary degeneration was visualized and discerned during sea lamprey metamorphosis by using laser scanning confocal microscopy. This method provides a powerful tool to study biliary atresia in a unique animal model.

  12. Chemical Characterization of Lipophilic Constituents in the Skin of Migratory Adult Sea Lamprey from the Great Lakes Region.

    Directory of Open Access Journals (Sweden)

    Amila A Dissanayake

    Full Text Available The sea lamprey (Petromzons marinus is an invasive ectoparasite of large-bodied fishes that adversely affects the fishing industry and ecology of the Laurentian Great Lakes. Lipid content in the whole sea lamprey and muscles, liver and kidney of metamorphosing larval stages has been reported. Similarly, the fatty acid profile of the rope tissues of sexually-mature male sea lampreys has also been reported. The average body weight of a sub-adult migratory sea lamprey is 250 g, which includes 14.4% skin (36 g. Our preliminary extraction data of an adult sea lamprey skin revealed that it contained approximately 8.5% of lipophilic compounds. Lamprey skin is home to a naturally aversive compound (an alarm cue that is being developed into a repellent for use in pest management. As part of an ongoing investigation to identify the chemical structure of the sea lamprey alarm cue, we extracted the skin with water and methanol, respectively. The methanolic extract (1.55% contained exclusively lipophilic compounds and did not include the alarm cue. We chemically characterized all compounds present in the methanolic extract as cholesterol esters (CE, tri- and di-glycerides (TG and DG, cholesterol, free fatty acids (FFA and minor amounts of plasticizers. The free fatty acids fraction was composed of saturated (41.8%, monounsaturated (40.7% and polyunsaturated (17.4% fatty acids, respectively. The plasticizers characterized were phthalate and benzoate and found to be 0.95 mg and 2.54 mg, respectively, per adult sea lamprey skin. This is the first report of the chemical characterization of all the lipophilic constituents in the skin of sub-adult migratory sea lamprey. The CEs isolated and characterized from sea lamprey skin are also for the first time.

  13. Quantitative Determination of Ceramide Molecular Species in Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Samar Al Makdessi

    2016-09-01

    Full Text Available Background/Aims: The activation of acid sphingomyelinase by cellular stress or receptors or the de novo synthesis lead to the formation of ceramide (N-acylsphingosine, which in turn modifies the biophysical properties of cellular membrane and greatly amplifies the intensity of the initial signal. Ceramide, which acts by re-organizing a given signalosome rather than being a second messenger, has many functions in infection biology, cancer, cardiovascular syndromes, and immune regulation. Experimental studies on the infection of human cells with different bacterial agents demonstrated the activation of the acid sphingomyelinase/ceramide system. Moreover, the release of ceramide was found to be a requisite for the uptake of the pathogen. Considering the particular importance of the cellular role of ceramide, it was necessary to develop sensitive and accurate methods for its quantification. Methods: Here, we describe a method quantifying ceramide in dendritic cells and defining the different fatty acids (FA bound to sphingosine. The main steps of the method include extraction of total lipids, separation of the ceramide by thin-layer chromatography, derivatization of ceramide-fatty acids (Cer-FA, and quantitation of these acids in their methyl form by gas chromatography on polar capillary columns. The identification of FA was achieved by means of known standards and confirmed by mass spectrometry. Results: FA ranging between C10 and C24 could be detected and quantified. The concentration of the sum of Cer-FA amounted to 14.88 ± 8.98 nmol/106 cells (n=10. Oleic acid, which accounted for approximately half of Cer-FA (7.73 ± 6.52 nmol/106 cells was the predominant fatty acid followed by palmitic acid (3.47 ± 1.54 nmol/106 cells. Conclusion: This highly sensitive method allows the quantification of different molecular species of ceramides.

  14. Relative contributions of sampling effort, measuring, and weighing to precision of larval sea lamprey biomass estimates

    Science.gov (United States)

    Slade, Jeffrey W.; Adams, Jean V.; Cuddy, Douglas W.; Neave, Fraser B.; Sullivan, W. Paul; Young, Robert J.; Fodale, Michael F.; Jones, Michael L.

    2003-01-01

    We developed two weight-length models from 231 populations of larval sea lampreys (Petromyzon marinus) collected from tributaries of the Great Lakes: Lake Ontario (21), Lake Erie (6), Lake Huron (67), Lake Michigan (76), and Lake Superior (61). Both models were mixed models, which used population as a random effect and additional environmental factors as fixed effects. We resampled weights and lengths 1,000 times from data collected in each of 14 other populations not used to develop the models, obtaining a weight and length distribution from reach resampling. To test model performance, we applied the two weight-length models to the resampled length distributions and calculated the predicted mean weights. We also calculated the observed mean weight for each resampling and for each of the original 14 data sets. When the average of predicted means was compared to means from the original data in each stream, inclusion of environmental factors did not consistently improve the performance of the weight-length model. We estimated the variance associated with measures of abundance and mean weight for each of the 14 selected populations and determined that a conservative estimate of the proportional contribution to variance associated with estimating abundance accounted for 32% to 95% of the variance (mean = 66%). Variability in the biomass estimate appears more affected by variability in estimating abundance than in converting length to weight. Hence, efforts to improve the precision of biomass estimates would be aided most by reducing the variability associated with estimating abundance.

  15. Heavy metals determination in aquatic species for food purposes

    Energy Technology Data Exchange (ETDEWEB)

    Locatelli, C.; Torsi, G. [Bologna Univ., Bologna (Italy). Dept. of Chemistry G. Ciamician

    2001-02-01

    New analytical procedures and sample mineralizations are proposed regarding the determination of arsenic, selenium, copper, lead, cadmium, zinc and mercury in matrices involved in food chain as mussel, clams and fishes. As regards As, Se, Cu, Pb, Cd and Zn determinations. H{sub 2}SO{sub 4}-HNO{sub 3} acidic mixture is used for the digestion is performed using a concentrated supra pure H{sub 2}SO{sub 4}-K{sub 2}Cr{sub 2}O{sub 7} mixture and the results are compared with those from other conventional methods (DPASV) are employed for determining simultaneously selenium, arsenic and copper, lead, cadmium, zinc, respectively, while mercury determination is carried out by the cold vapour atomic absorption spectrometry (CV-AAS) with reduction with SnCl{sub 2}. The voltammetric measurements were performed using a conventional three-electrode cell and the ammonia-ammonium chloride buffer (ph 9.3) as supporting electrolyte. For all the elements, in addition to the detection limits, precision and accuracy data are also reported: the former, expressed as relative standard deviation (S{sub r}), and the latter, expressed as relative error (e), are in all cases between 3 to 6%. [Italian] Viene proposta una nuova procedura analitica ed una nuova mineralizzazione del campione per la determinazione di arsenico, selenio, rame, piombo, cadmio, zinco e mercurio in matrici coinvolte nella catena alimentare come mitili e pesci. Per la determinazione di As, Se, Cu, Pb, Cd, Zn, le matrici sono state mineralizzate con una miscela acida H{sub 2}SO{sub 4}-HNO{sub 3}. Nel caso del Hg, la mineralizzazione del campione e' stata effettuata mediante una miscela H{sub 2}SO{sub 4}-K{sub 2}Cr{sub 2}O{sub 7} ed i risultati confrontati con quelli ottenuti impiegando altri metodi convenzionali. Per la simultanea determinazione di arsenico, selenio, rame, piombo, cadmio, zinco, sono state impiegate la voltammetria differenziale pulsata catodica (DPCSV) ed anodica (DPASV), mentre il mercurio e

  16. Phylogeographical analysis reveals multiple conservation units in brook lampreys Lampetra planeri of Portuguese streams.

    Science.gov (United States)

    Pereira, A M; Robalo, J I; Freyhof, J; Maia, C; Fonseca, J P; Valente, A; Almada, V C

    2010-08-01

    The populations of brook lamprey Lampetra planeri of Portuguese Rivers were analysed phylogeographically using a fragment of 644 bp of the mitochondrial control region of 158 individuals from six populations. Samples representing L. planeri and migratory lampreys Lampetra fluviatilis of rivers draining to the North Sea and the Baltic Sea were also included to assess the relationships of Portuguese samples. The data support a clear differentiation of all the populations studied. Several populations, which are isolated among themselves and also from the migratory lampreys, proved to be entirely composed of private haplotypes, a finding that supports some time of independent evolutionary history for these populations. This, combined with the geographic confinement to small water bodies, justifies the recognition of at least four conservation units in the Portuguese rivers Sado, São Pedro, Nabão and Inha.

  17. An annotated bibliography for lamprey habitat in the White Salmon River, Washington

    Science.gov (United States)

    Allen, M. Brady

    2012-01-01

    The October 2011 decommissioning of Condit Dam on the White Salmon River at river kilometer (rkm) 5.3 removed a significant fish passage barrier from the White Salmon River basin for the first time in nearly a century. This affords an opportunity to regain a potentially important drainage basin for Pacific lamprey (Entosphenus tridentatus) production. In anticipation of Pacific lamprey recolonization or reintroduction, aquatic resource managers, such as the Yakama Nation (YN), are planning to perform surveys in the White Salmon River and its tributaries. The likely survey objectives will be to investigate the presence of lamprey, habitat conditions, and habitat availability. In preparation for this work, a compilation and review of the relevant aquatic habitat and biological information on the White Salmon River was conducted. References specific to the White Salmon River were collected and an annotated bibliography was produced including reports containing:

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

    Science.gov (United States)

    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.

  19. Effect of human chorionic gonadotropin on sexual maturation, sex steroids and thyroid hormone levels in Caspian lamprey (Caspiomyzon wagneri Kessler, 1870)

    OpenAIRE

    Abedi, M.; Mojazi Amiri, B.; Abdoli, A.; Javanshir, A.; Benam, S.; Namdarian, A.

    2017-01-01

    The objective of this study was to determine the effect of human chorionic gonadotropin (hCG) on sexual maturation, plasma sex steroids [17β-estradiol, (E2) and 17α-hydroxy progesterone (17α_OHP)] and thyroid hormones (triiodothyronine, T3 and thyroxin, T4) levels in upstream - migrating Caspian lamprey. During the experiment, 36 fish (24 females and 12 males) in spring 2013 and 36 fish (24 females and 12 males) in fall 2013 were collected from the Shirud River estuary in Mazandaran Province,...

  20. Phylogenetic distribution of a male pheromone that may exploit a nonsexual preference in lampreys.

    Science.gov (United States)

    Buchinger, T J; Bussy, U; Li, K; Wang, H; Huertas, M; Baker, C F; Jia, L; Hayes, M C; Li, W; Johnson, N S

    2017-12-01

    Pheromones are among the most important sexual signals used by organisms throughout the animal kingdom. However, few are identified in vertebrates, leaving the evolutionary mechanisms underlying vertebrate pheromones poorly understood. Pre-existing biases in receivers' perceptual systems shape visual and auditory signalling systems, but studies on how receiver biases influence the evolution of pheromone communication remain sparse. The lamprey Petromyzon marinus uses a relatively well-understood suite of pheromones and offers a unique opportunity to study the evolution of vertebrate pheromone communication. Previous studies indicate that male signalling with the mating pheromone 3-keto petromyzonol sulphate (3kPZS) may exploit a nonsexual attraction to juvenile-released 3kPZS that guides migration into productive rearing habitat. Here, we infer the distribution of male signalling with 3kPZS using a phylogenetic comparison comprising six of 10 genera and two of three families. Our results indicate that only P. marinus and Ichthyomyzon castaneus release 3kPZS at high rates. Olfactory and behavioural assays with P. marinus, I. castaneus and a subset of three other species that do not use 3kPZS as a sexual signal indicate that male signalling might have driven the evolution of female adaptations to detect 3kPZS with specific olfactory mechanisms and respond to 3kPZS with targeted attraction relevant during mate search. We postulate that 3kPZS communication evolved independently in I. castaneus and P. marinus, but cannot eliminate the alternative that other species lost 3kPZS communication. Regardless, our results represent a rare macroevolutionary investigation of a vertebrate pheromone and provide insight into the evolutionary mechanisms underlying pheromone communication. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  1. Chondrogenesis of the branchial skeleton in embryonic sea lamprey, Petromyzon marinus.

    Science.gov (United States)

    Morrison, S L; Campbell, C K; Wright, G M

    2000-11-01

    This study provides concise temporal and spatial characteristics of branchial chondrogenesis in embryonic sea lamprey, Petromyzon marinus, using high resolution light microscopy, transmission electron, and immunoelectron microscopy. Prechondrogenic condensations representing the first branchial arch appeared first in the mid-region of the third pharyngeal arch at 13 days post-fertilization (pf). Cartilage differentiation, defined by the presence of the unique, fibrillar, non-collagenous matrix protein characteristic of branchial cartilage, was first observed at 14 days pf. Development of lamprey branchial cartilage appeared unusual compared to that in jawed fishes, in that precartilage condensations appear as a one-cell wide orderly stack of flattened cells that extend by the addition of one dorsal and one ventral condensation. Development of lamprey gill arches from three condensations that fuse to form a single skeletal element differs from the developing gill arches of jawed fishes, where more than one skeletal element forms from a single condensation. The initial orderly arrangement of cells in the lamprey branchial prechondrogenic condensations remains throughout development. Once chondrification of the condensations begins, the branchial arches start to grow. Initially, growth occurs as a result of matrix secretion and cell migration. Later in development, the arches grow mainly by cell proliferation and enlargement. This study defines the morphology and timing of lamprey branchial chondrogenesis. Studies of lamprey chondrogenesis provide not only insight into the developmental biology of a unique non-collagenous cartilage in a primitive vertebrate but also into the general evolution of the skeletal system in vertebrates. Copyright 2000 Wiley-Liss, Inc.

  2. Anatomy of the lamprey ear: morphological evidence for occurrence of horizontal semicircular ducts in the labyrinth of Petromyzon marinus

    Science.gov (United States)

    Maklad, Adel; Reed, Caitlyn; Johnson, Nicholas S.; Fritzsch, Bernd

    2014-01-01

    In jawed (gnathostome) vertebrates, the inner ears have three semicircular canals arranged orthogonally in the three Cartesian planes: one horizontal (lateral) and two vertical canals. They function as detectors for angular acceleration in their respective planes. Living jawless craniates, cyclostomes (hagfish and lamprey) and their fossil records seemingly lack a lateral horizontal canal. The jawless vertebrate hagfish inner ear is described as a torus or doughnut, having one vertical canal, and the jawless vertebrate lamprey having two. These observations on the anatomy of the cyclostome (jawless vertebrate) inner ear have been unchallenged for over a century, and the question of how these jawless vertebrates perceive angular acceleration in the yaw (horizontal) planes has remained open. To provide an answer to this open question we reevaluated the anatomy of the inner ear in the lamprey, using stereoscopic dissection and scanning electron microscopy. The present study reveals a novel observation: the lamprey has two horizontal semicircular ducts in each labyrinth. Furthermore, the horizontal ducts in the lamprey, in contrast to those of jawed vertebrates, are located on the medial surface in the labyrinth rather than on the lateral surface. Our data on the lamprey horizontal duct suggest that the appearance of the horizontal canal characteristic of gnathostomes (lateral) and lampreys (medial) are mutually exclusive and indicate a parallel evolution of both systems, one in cyclostomes and one in gnathostome ancestors.

  3. Lamprey immune protein-1 (LIP-1) from Lampetra japonica induces cell cycle arrest and cell death in HeLa cells.

    Science.gov (United States)

    Chi, Xiaoyuan; Su, Peng; Bi, Dan; Tai, Zhao; Li, Yingying; Pang, Yue; Li, Qingwei

    2018-04-01

    The lamprey (Lampetra japonica), a representative of the jawless vertebrates, is the oldest extant species in the world. LIP-1, which has a jacalin-like domain and an aerolysin pore-forming domain, has previously been identified in Lampetra japonica. However, the structure and function of the LIP-1 protein have not been described. In this study, the LIP-1 gene was overexpressed in HeLa cells and H293T cells. The results showed that the overexpression of LIP-1 in HeLa cells significantly elevated LDH release (P HeLa cells, while it had no effect on H293T cell organelles. Array data indicated that overexpression of LIP-1 primarily upregulated P53 signaling pathways in HeLa cells. Cell cycle assay results confirmed that LIP-1 caused arrest in the G 2 /M phase of the cell cycle in HeLa cells. In summary, our findings provide insights into the function and characterization of LIP-1 genes in vertebrates and establish the foundation for further research into the biological function of LIP-1. Our observations suggest that this lamprey protein has the potential for use in new applications in the medical field. Copyright © 2018. Published by Elsevier Ltd.

  4. Odor-conditioned rheotaxis of the sea lamprey: modeling, analysis and validation

    International Nuclear Information System (INIS)

    Choi, Jongeun; Jeon, Soo; Johnson, Nicholas S; Brant, Cory O; Li, Weiming

    2013-01-01

    Mechanisms for orienting toward and locating an odor source are sought in both biology and engineering. Chemical ecology studies have demonstrated that adult female sea lamprey show rheotaxis in response to a male pheromone with dichotomous outcomes: sexually mature females locate the source of the pheromone whereas immature females swim by the source and continue moving upstream. Here we introduce a simple switching mechanism modeled after odor-conditioned rheotaxis for the sea lamprey as they search for the source of a pheromone in a one-dimensional riverine environment. In this strategy, the females move upstream only if they detect that the pheromone concentration is higher than a threshold value and drifts down (by turning off control action to save energy) otherwise. In addition, we propose various uncertainty models such as measurement noise, actuator disturbance, and a probabilistic model of a concentration field in turbulent flow. Based on the proposed model with uncertainties, a convergence analysis showed that with this simplistic switching mechanism, the lamprey converges to the source location on average in spite of all such uncertainties. Furthermore, a slightly modified model and its extensive simulation results explain the behaviors of immature female lamprey near the source location. (paper)

  5. 15alpha-Hydroxyprogesterone in male sea lampreys, Petromyzon marinus L

    Czech Academy of Sciences Publication Activity Database

    Bryan, M. B.; Scott, A. P.; Černý, Ivan; Young, B. A.; Li, W.

    2004-01-01

    Roč. 69, - (2004), s. 473-481 ISSN 0039-128X Institutional research plan: CEZ:AV0Z4055905 Keywords : steroid * 15alpha-hydroxyprogesterone * sea lamprey Subject RIV: CC - Organic Chemistry Impact factor: 2.337, year: 2004

  6. Cloning and analysis of an HMG gene from the lamprey Lampetra fluviatilis

    DEFF Research Database (Denmark)

    Sharman, A C; Hay-Schmidt, Anders; Holland, P W

    1997-01-01

    Evolution has shaped the organisation of vertebrate genomes, including the human genome. To shed further light on genome history, we have cloned and analysed an HMG gene from lamprey, representing one of the earliest vertebrate lineages. Genes of the HMG1/2 family encode chromosomal proteins...

  7. Spatial and Ontogenetic Variation in Mercury in Lake Superior Basin Sea Lamprey (Petromyzon marinus).

    Science.gov (United States)

    Moses, Sara K; Polkinghorne, Christine N; Mattes, William P; Beesley, Kimberly M

    2018-01-01

    Mercury concentrations were measured in eggs, larvae, and adult spawning-phase sea lampreys (Petromyzon marinus) collected in tributaries of Lake Superior to investigate spatial and ontogenetic variation. There were significant differences in mercury concentrations between all three life stages, with levels highest in adults (mean = 3.01 µg/g), followed by eggs (mean = 0.942 µg/g), and lowest in larvae (mean = 0.455 µg/g). There were no significant differences in mercury concentrations by location for any life stage or by sex in adults. Mercury was not correlated with adult or larval lamprey length or mass. Mercury levels in adult lampreys exceeded U.S. and Canadian federal guidelines for human consumption. Mercury concentrations in all life stages exceeded criteria for the protection of piscivorous wildlife, posing a threat to local fish, birds, and mammals. High mercury levels in adult lampreys combined with their semelparous life history make them a potential source of lake-derived mercury to spawning streams.

  8. Anatomical recovery of the GABAergic system after a complete spinal cord injury in lampreys.

    Science.gov (United States)

    Romaus-Sanjurjo, D; Valle-Maroto, S M; Barreiro-Iglesias, A; Fernández-López, B; Rodicio, M C

    2018-03-15

    Lampreys recover locomotion spontaneously several weeks after a complete spinal cord injury. Dysfunction of the GABAergic system following SCI has been reported in mammalian models. So, it is of great interest to understand how the GABAergic system of lampreys adapts to the post-injury situation and how this relates to spontaneous recovery. The spinal cord of lampreys contains 3 populations of GABAergic neurons and most of the GABAergic innervation of the spinal cord comes from these local cells. GABAB receptors are expressed in the spinal cord of lampreys and they play important roles in the control of locomotion. The aims of the present study were to quantify: 1) the changes in the number of GABAergic neurons and innervation of the spinal cord and 2) the changes in the expression of the gabab receptor subunits b1 and b2 in the spinal cord of the sea lamprey after SCI. We performed complete spinal cord transections at the level of the fifth gill of mature larval lampreys and GABA immunohistochemistry or gabab in situ hybridization experiments. Animals were analysed up to 10 weeks post-lesion (wpl), when behavioural analyses showed that they recovered normal appearing locomotion (stage 6 in the Ayer's scale of locomotor recovery). We observed a significant decrease in the number of GABA-ir cells and fibres 1 h after lesion both rostral and caudal to the lesion site. GABA-ir cell numbers and innervation were recovered to control levels 1 to 2 wpl. At 1, 4 and 10 wpl the expression of gabab1 and gabab2 transcripts was significantly decreased in the spinal cord compared to control un-lesioned animals. This is the first study reporting the quantitative long-term changes in the number of GABAergic cells and fibres and in the expression of gabab receptors in the spinal cord of any vertebrate following a traumatic SCI. Our results show that in lampreys there is a full recovery of the GABAergic neurons and a decrease in the expression of gabab receptors when functional

  9. Determinants of Mammal and Bird Species Richness in China Based on Habitat Groups.

    Directory of Open Access Journals (Sweden)

    Haigen Xu

    Full Text Available Understanding the spatial patterns in species richness is a central issue in macroecology and biogeography. Analyses that have traditionally focused on overall species richness limit the generality and depth of inference. Spatial patterns of species richness and the mechanisms that underpin them in China remain poorly documented. We created a database of the distribution of 580 mammal species and 849 resident bird species from 2376 counties in China and established spatial linear models to identify the determinants of species richness and test the roles of five hypotheses for overall mammals and resident birds and the 11 habitat groups among the two taxa. Our result showed that elevation variability was the most important determinant of species richness of overall mammal and bird species. It is indicated that the most prominent predictors of species richness varied among different habitat groups: elevation variability for forest and shrub mammals and birds, temperature annual range for grassland and desert mammals and wetland birds, net primary productivity for farmland mammals, maximum temperature of the warmest month for cave mammals, and precipitation of the driest quarter for grassland and desert birds. Noteworthily, main land cover type was also found to obviously influence mammal and bird species richness in forests, shrubs and wetlands under the disturbance of intensified human activities. Our findings revealed a substantial divergence in the species richness patterns among different habitat groups and highlighted the group-specific and disparate environmental associations that underpin them. As we demonstrate, a focus on overall species richness alone might lead to incomplete or misguided understanding of spatial patterns. Conservation priorities that consider a broad spectrum of habitat groups will be more successful in safeguarding the multiple services of biodiversity.

  10. Lampreys, the jawless vertebrates, contain only two ParaHox gene clusters.

    Science.gov (United States)

    Zhang, Huixian; Ravi, Vydianathan; Tay, Boon-Hui; Tohari, Sumanty; Pillai, Nisha E; Prasad, Aravind; Lin, Qiang; Brenner, Sydney; Venkatesh, Byrappa

    2017-08-22

    ParaHox genes ( Gsx , Pdx , and Cdx ) are an ancient family of developmental genes closely related to the Hox genes. They play critical roles in the patterning of brain and gut. The basal chordate, amphioxus, contains a single ParaHox cluster comprising one member of each family, whereas nonteleost jawed vertebrates contain four ParaHox genomic loci with six or seven ParaHox genes. Teleosts, which have experienced an additional whole-genome duplication, contain six ParaHox genomic loci with six ParaHox genes. Jawless vertebrates, represented by lampreys and hagfish, are the most ancient group of vertebrates and are crucial for understanding the origin and evolution of vertebrate gene families. We have previously shown that lampreys contain six Hox gene loci. Here we report that lampreys contain only two ParaHox gene clusters (designated as α- and β-clusters) bearing five ParaHox genes ( Gsxα , Pdxα , Cdxα , Gsxβ , and Cdxβ ). The order and orientation of the three genes in the α-cluster are identical to that of the single cluster in amphioxus. However, the orientation of Gsxβ in the β-cluster is inverted. Interestingly, Gsxβ is expressed in the eye, unlike its homologs in jawed vertebrates, which are expressed mainly in the brain. The lamprey Pdxα is expressed in the pancreas similar to jawed vertebrate Pdx genes, indicating that the pancreatic expression of Pdx was acquired before the divergence of jawless and jawed vertebrate lineages. It is likely that the lamprey Pdxα plays a crucial role in pancreas specification and insulin production similar to the Pdx of jawed vertebrates.

  11. Growth and survival of sea lampreys from metamorphosis to spawning in Lake Huron

    Science.gov (United States)

    Swink, William D.; Johnson, Nicholas S.

    2014-01-01

    Larval Sea Lampreys Petromyzon marinus live burrowed in stream bottoms and then metamorphose into their parasitic stage. Among larvae that metamorphose in a given year (i.e., parasitic cohort), autumn out-migrants (October–December) to the Laurentian Great Lakes can feed on fish for up to 6 months longer than spring outmigrants (March–May), which overwinter in streams without feeding. We evaluated whether the season of outmigration affected growth or survival of newlymetamorphosed Sea Lampreys in LakeHuron. Newlymetamorphosed individuals (n=2,718) from three parasitic cohorts were netted during their out-migration from BlackMallard Creek, Michigan, to LakeHuron during autumn 1997 through spring 2000; each out-migrant was injected with a sequentially numbered coded wire tag and was released back into the creek. After up to 18 months of feeding in the Great Lakes, 224 (8.2%) Sea Lampreys were recaptured (in 1999–2001) as upstream-migrating adults in tributaries to Lakes Huron and Michigan. Recovery rates of autumn and spring out-migrants as adults were 9.4% and 7.8%, respectively, and these rates did not significantly differ. Overwinter feeding (i.e., as parasites) by autumn out-migrants did not produce adult mean sizes greater than those of spring out-migrants. Because we detected no growth or survival differences between autumn and spring out-migrants, the capture of newly metamorphosed Sea Lampreys at any point during their out-migration should provide equal reductions in damage to Great Lakes fisheries. The absence of a difference in growth or survival between autumn and spring out-migrants is an aspect of Sea Lamprey life history that yields resiliency to this invasive parasite and complicates efforts for its control in the Great Lakes.

  12. Genetic sex determination in Astatotilapia calliptera, a prototype species for the Lake Malawi cichlid radiation

    Science.gov (United States)

    Peterson, Erin N.; Cline, Maggie E.; Moore, Emily C.; Roberts, Natalie B.; Roberts, Reade B.

    2017-06-01

    East African cichlids display extensive variation in sex determination systems. The species Astatotilapia calliptera is one of the few cichlids that reside both in Lake Malawi and in surrounding waterways. A. calliptera is of interest in evolutionary studies as a putative immediate outgroup species for the Lake Malawi species flock and possibly as a prototype ancestor-like species for the radiation. Here, we use linkage mapping to test association of sex in A. calliptera with loci that have been previously associated with genetic sex determination in East African cichlid species. We identify a male heterogametic XY system segregating at linkage group (LG) 7 in an A. calliptera line that originated from Lake Malawi, at a locus previously shown to act as an XY sex determination system in multiple species of Lake Malawi cichlids. Significant association of genetic markers and sex produce a broad genetic interval of approximately 26 megabases (Mb) using the Nile tilapia genome to orient markers; however, we note that the marker with the strongest association with sex is near a gene that acts as a master sex determiner in other fish species. We demonstrate that alleles of the marker are perfectly associated with sex in Metriaclima mbenjii, a species from the rock-dwelling clade of Lake Malawi. While we do not rule out the possibility of other sex determination loci in A. calliptera, this study provides a foundation for fine mapping of the cichlid sex determination gene on LG7 and evolutionary context regarding the origin and persistence of the LG7 XY across diverse, rapidly evolving lineages.

  13. Shifting patterns of nitrogen excretion and amino acid catabolism capacity during the life cycle of the sea lamprey (Petromyzon marinus).

    Science.gov (United States)

    Wilkie, Michael P; Claude, Jaime F; Cockshutt, Amanda; Holmes, John A; Wang, Yuxiang S; Youson, John H; Walsh, Patrick J

    2006-01-01

    The jawless fish, the sea lamprey (Petromyzon marinus), spends part of its life as a burrow-dwelling, suspension-feeding larva (ammocoete) before undergoing a metamorphosis into a free swimming, parasitic juvenile that feeds on the blood of fishes. We predicted that animals in this juvenile, parasitic stage have a great capacity for catabolizing amino acids when large quantities of protein-rich blood are ingested. The sixfold to 20-fold greater ammonia excretion rates (J(Amm)) in postmetamorphic (nonfeeding) and parasitic lampreys compared with ammocoetes suggested that basal rates of amino acid catabolism increased following metamorphosis. This was likely due to a greater basal amino acid catabolizing capacity in which there was a sixfold higher hepatic glutamate dehydrogenase (GDH) activity in parasitic lampreys compared with ammocoetes. Immunoblotting also revealed that GDH quantity was 10-fold and threefold greater in parasitic lampreys than in ammocoetes and upstream migrant lampreys, respectively. Higher hepatic alanine and aspartate aminotransferase activities in the parasitic lampreys also suggested an enhanced amino acid catabolizing capacity in this life stage. In contrast to parasitic lampreys, the twofold larger free amino acid pool in the muscle of upstream migrant lampreys confirmed that this period of natural starvation is accompanied by a prominent proteolysis. Carbamoyl phosphate synthetase III was detected at low levels in the liver of parasitic and upstream migrant lampreys, but there was no evidence of extrahepatic (muscle, intestine) urea production via the ornithine urea cycle. However, detection of arginase activity and high concentrations of arginine in the liver at all life stages examined infers that arginine hydrolysis is an important source of urea. We conclude that metamorphosis is accompanied by a metabolic reorganization that increases the capacity of parasitic sea lampreys to catabolize intermittently large amino acid loads arising

  14. A method for determination of cadmium species in solid waste leachates

    DEFF Research Database (Denmark)

    Christensen, Thomas H.; Xu Ze Lun

    1989-01-01

    A procedure has been developed for determination of cadmium (Cd) species in solid waste leachates employing a cation exchange resin (Chelex 100) in a batch-column-batch sequence. The procedure allows for determination of free divalent Cd (Cd2+), labile Cd complexes, slowly labile Cd complexes...

  15. Descending brain neurons in larval lamprey: Spinal projection patterns and initiation of locomotion

    Science.gov (United States)

    Shaw, Albert C.; Jackson, Adam W.; Holmes, Tamra; Thurman, Suzie; Davis, G.R.; McClellan, Andrew D.

    2010-01-01

    In larval lamprey, partial lesions were made in the rostral spinal cord to determine which spinal tracts are important for descending activation of locomotion and to identify descending brain neurons that project in these tracts. In whole animals and in vitro brain/spinal cord preparations, brain-initiated spinal locomotor activity was present when the lateral or intermediate spinal tracts were spared but usually was abolished when the medial tracts were spared. We previously showed that descending brain neurons are located in eleven cell groups, including reticulospinal (RS) neurons in the mesenecephalic reticular nucleus (MRN) as well as the anterior (ARRN), middle (MRRN), and posterior (PRRN) rhombencephalic reticular nuclei. Other descending brain neurons are located in the diencephalic (Di) as well as the anterolateral (ALV), dorsolateral (DLV), and posterolateral (PLV) vagal groups. In the present study, the Mauthner and auxillary Mauthner cells, most neurons in the Di, ALV, DLV, and PLV cell groups, and some neurons in the ARRN and PRRN had crossed descending axons. The majority of neurons projecting in medial spinal tracts included large identified Müller cells and neurons in the Di, MRN, ALV, and DLV. Axons of individual descending brain neurons usually did not switch spinal tracts, have branches in multiple tracts, or cross the midline within the rostral cord. Most neurons that projected in the lateral/intermediate spinal tracts were in the ARRN, MRRN, and PRRN. Thus, output neurons of the locomotor command system are distributed in several reticular nuclei, whose neurons project in relatively wide areas of the cord. PMID:20510243

  16. Quantification of Oxidized and Unsaturated Bile Alcohols in Sea Lamprey Tissues by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Ke Li

    2016-08-01

    Full Text Available A sensitive and reliable method was developed and validated for the determination of unsaturated bile alcohols in sea lamprey tissues using liquid-liquid extraction and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS. The liver, kidney, and intestine samples were extracted with acetonitrile and defatted by n-hexane. Gradient UHPLC separation was performed using an Acquity BEH C18 column with a mobile phase of water and methanol containing 20 mM triethylamine. Multiple reaction monitoring modes of precursor-product ion transitions for each analyte was used. This method displayed good linearity, with correlation coefficients greater than 0.99, and was validated. Precision and accuracy (RSD % were in the range of 0.31%–5.28%, while mean recoveries were between 84.3%–96.3%. With this technique, sea lamprey tissue samples were analyzed for unsaturated bile alcohol analytes. This method is practical and particularly suitable for widespread putative pheromone residue analysis.

  17. Land-use change interacts with climate to determine elevational species redistribution.

    Science.gov (United States)

    Guo, Fengyi; Lenoir, Jonathan; Bonebrake, Timothy C

    2018-04-03

    Climate change is driving global species redistribution with profound social and economic impacts. However, species movement is largely constrained by habitat availability and connectivity, of which the interaction effects with climate change remain largely unknown. Here we examine published data on 2798 elevational range shifts from 43 study sites to assess the confounding effect of land-use change on climate-driven species redistribution. We show that baseline forest cover and recent forest cover change are critical predictors in determining the magnitude of elevational range shifts. Forest loss positively interacts with baseline temperature conditions, such that forest loss in warmer regions tends to accelerate species' upslope movement. Consequently, not only climate but also habitat loss stressors and, importantly, their synergistic effects matter in forecasting species elevational redistribution, especially in the tropics where both stressors will increase the risk of net lowland biotic attrition.

  18. Simultaneous determination of arsenic, selenium and antimony species using HPLC/ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Lindemann, T.; Prange, A.; Neidhart, B. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Physikalische und Chemische Analytik; Dannecker, W. [Univ. of Hamburg (Germany). Inst. for Inorganic and Applied Chemistry

    1999-07-01

    A new method for the simultaneous separation and determination of four arsenic species [As(III), As(V), monomethylarsonic acid and dimethylarsinic acid], three selenium species [Se(IV), Se(VI) and selenomethionine] as well as Sb(III) and Sb(V) is presented. The speciation was achieved by on-line coupling of anion exchange high-performance liquid chromatography (HPLC) with inductively coupled plasma mass spectrometry (ICP-MS). Chromatographic parameters such as the composition and pH of the mobile phase were optimised. Limits of detection are below 4.5 {mu}g L{sup -1} (as element) for Sb(III) and the selenium species and below 0.5 {mu}g L{sup -1} for the other species. Precisions of retention times were better than 2% RSD and of peak areas better than 8% RSD for all the species investigated. (orig.) With 5 figs., 3 tabs., 41 refs.

  19. Commonness of Amazonian palm (Arecaceae) species: Cross-scale links and potential determinants

    DEFF Research Database (Denmark)

    Kristiansen, Thea; Svenning, J.-C.; Grández, César

    2009-01-01

    was positively related to topographic niche breadth. Stem height correlated with continental range size and was the only species life-history trait related to any commonness measure. Distance from the study area to a species' range centre did not influence any of the commonness measures. The factors determining......The mechanisms that cause variation in commonness (abundances and range sizes) of species remain debated in ecology, and a repeatedly observed pattern is the positive relation between local abundances and larger scale range sizes. We used the Amazonian palm species (Arecaceae) to investigate...... the dependence between and potential determinants of commonness across three (local, landscape, continental) spatial scales. Commonness at the smaller scales (local abundance, landscape frequency) was estimated using data from 57 transects (5 × 500 m) in primary, non-inundated (terra firme) rainforest...

  20. Applying iPSCs for Preserving Endangered Species and Elucidating the Evolution of Mammalian Sex Determination.

    Science.gov (United States)

    Honda, Arata

    2018-04-06

    The endangered species Tokudaia osimensis has the unique chromosome constitution of 2n = 25, with an XO/XO sex chromosome configuration (2n = 25; XO). There is urgency to preserve this species and to elucidate the regulator(s) that can discriminate the males and females arising from the indistinguishable sex chromosome constitution. However, it is not realistic to examine this rare animal species by sacrificing individuals. Recently, true naïve induced pluripotent stem cells were successfully generated from a female T. osimensis, and the sexual plasticity of its germ cells was elucidated. This achievement constitutes the basis of an attractive research area, including embryonic fate determination, sex determination, and factor(s) that can replace the Y chromosome. In this essay, concrete strategies to conserve rare animal species and to reveal their specific characteristics using other compatible and abundant animals are proposed. © 2018 WILEY Periodicals, Inc.

  1. Can establishment success be determined through demographic parameters? A case study on five introduced bird species.

    Directory of Open Access Journals (Sweden)

    Ana Sanz-Aguilar

    Full Text Available The dominant criterion to determine when an introduced species is established relies on the maintenance of a self-sustaining population in the area of introduction, i.e. on the viability of the population from a demographic perspective. There is however a paucity of demographic studies on introduced species, and establishment success is thus generally determined by expert opinion without undertaking population viability analyses (PVAs. By means of an intensive five year capture-recapture monitoring program (involving >12,000 marked individuals we studied the demography of five introduced passerine bird species in southern Spain which are established and have undergone a fast expansion over the last decades. We obtained useful estimates of demographic parameters (survival and reproduction for one colonial species (Ploceus melanocephalus, confirming the long-term viability of its local population through PVAs. However, extremely low recapture rates prevented the estimation of survival parameters and population growth rates for widely distributed species with low local densities (Estrilda troglodytes and Amandava amandava but also for highly abundant yet non-colonial species (Estrilda astrild and Euplectes afer. Therefore, determining the establishment success of introduced passerine species by demographic criteria alone may often be troublesome even when devoting much effort to field-work. Alternative quantitative methodologies such as the analysis of spatio-temporal species distributions complemented with expert opinion deserve thus their role in the assessment of establishment success of introduced species when estimates of demographic parameters are difficult to obtain, as is generally the case for non-colonial, highly mobile passerines.

  2. Thyroid hormone and retinoid X receptor function and expression during sea lamprey (Petromyzon marinus) metamorphosis.

    Science.gov (United States)

    Manzon, Lori A; Youson, John H; Holzer, Guillaume; Staiano, Leopoldo; Laudet, Vincent; Manzon, Richard G

    2014-08-01

    Sea lampreys (Petromyzon marinus) are members of the ancient class Agnatha and undergo a metamorphosis that transforms blind, sedentary, filter-feeding larvae into free-swimming, parasitic juveniles. Thyroid hormones (THs) appear to be important for lamprey metamorphosis, however, serum TH concentrations are elevated in the larval phase, decline rapidly during early metamorphosis and remain low until metamorphosis is complete; these TH fluctuations are contrary to those of other metamorphosing vertebrates. Moreover, thyroid hormone synthesis inhibitors (goitrogens) induce precocious metamorphosis and exogenous TH treatments disrupt natural metamorphosis in P. marinus. Given that THs exert their effects by binding to TH nuclear receptors (TRs) that often act as heterodimers with retinoid X receptors (RXRs), we cloned and characterized these receptors from P. marinus and examined their expression during metamorphosis. Two TRs (PmTR1 and PmTR2) and three RXRs (PmRXRs) were isolated from P. marinus cDNA. Phylogenetic analyses group the PmTRs together on a branch prior to the gnathostome TRα/β split. The three RXRs also group together, but our data indicated that these transcripts are most likely either allelic variants of the same gene locus, or the products of a lamprey-specific duplication event. Importantly, these P. marinus receptors more closely resemble vertebrate as opposed to invertebrate chordate receptors. Functional analysis revealed that PmTR1 and PmTR2 can activate transcription of TH-responsive genes when treated with nanomolar concentrations of TH and they have distinct pharmacological profiles reminiscent of vertebrate TRβ and TRα, respectively. Also similar to other metamorphosing vertebrates, expression patterns of the PmTRs during lamprey metamorphosis suggest that PmTR1 has a dynamic, tissue-specific expression pattern that correlates with tissue morphogenesis and biochemical changes and PmTR2 has a more uniform expression pattern. This TR

  3. Species ecology determines the role of nitrogen nutrition in the frost tolerance of pine seedlings.

    Science.gov (United States)

    Toca, Andrei; Oliet, Juan A; Villar-Salvador, Pedro; Maroto, Judit; Jacobs, Douglass F

    2018-01-01

    Frost determines the evolution and distribution of plants in temperate and cold regions. Several environmental factors can influence frost acclimation of woody plants but the magnitude and direction of the effect of nitrogen (N) availability is controversial. We studied the effect of N availability on root and shoot frost tolerance in mid-fall and in winter in seedlings of four pines of contrasting ecology: Pinus nigra J.F. Arnold, P. pinaster Ait., P. pinea L. and P. halepensis Mill.. Organ N and soluble sugar concentration, and timing of cessation of shoot elongation were measured to assess the physiological mechanisms underlying frost acclimation. Nitrogen was supplied at high and low rates only during the pre-hardening period and at a moderate N rate during hardening in the fall. Shoot frost tolerance increased over winter while root frost tolerance did not change in any species. Pre-hardening N availability affected the frost tolerance of both roots and shoots, although the effect was species-specific: high N reduced the overall root and shoot frost tolerance in P. pinea and P. halepensis, and increased the frost tolerance in P. nigra, but had no effect in P. pinaster. Nitrogen supply in the fall consistently increased frost tolerance in all species. Differences in frost tolerance among species and N treatments were not explained by variations in organ N or soluble carbohydrate concentration, nor by timing of cessation of shoot elongation; however, the most frost tolerant species ceased elongation earlier than the least frost tolerant species. Despite the close phylogenetic relatedness of the studied species, the effect of N availability on seedling frost tolerance differed among species, indicating that species ecology (especially frost acclimation physiology) and timing of N supply drives the effect of N availability on frost tolerance of pine species. © The Author(s) 2017. Published by Oxford University Press. All rights reserved. For Permissions, please

  4. Reconnaissance On Chi-Square Test Procedure For Determining Two Species Association

    Science.gov (United States)

    Marisa, Hanifa

    2008-01-01

    Determining the assosiation of two species by using chi-square test has been published. Utility of this procedure to plants species at certain location, shows that the procedure could not find "ecologically" association. Tens sampling units have been made to record some weeds species in Indralaya, South Sumatera. Chi square test; Xt2 = N[|(ad)-(bc)|-(N/2)]2/mnrs (Eq:1) on two species (Cleome sp and Eleusine indica) of the weeds shows positive assosiation; while ecologically in nature, there is no relationship between them. Some alternatives are proposed to this problem; simplified chi-square test steps, make further study to find out ecologically association, or at last, ignore it.

  5. Origins of gonadotropin-releasing hormone (GnRH) in vertebrates: identification of a novel GnRH in a basal vertebrate, the sea lamprey.

    Science.gov (United States)

    Kavanaugh, Scott I; Nozaki, Masumi; Sower, Stacia A

    2008-08-01

    We cloned a cDNA encoding a novel (GnRH), named lamprey GnRH-II, from the sea lamprey, a basal vertebrate. The deduced amino acid sequence of the newly identified lamprey GnRH-II is QHWSHGWFPG. The architecture of the precursor is similar to that reported for other GnRH precursors consisting of a signal peptide, decapeptide, a downstream processing site, and a GnRH-associated peptide; however, the gene for lamprey GnRH-II does not have introns in comparison with the gene organization for all other vertebrate GnRHs. Lamprey GnRH-II precursor transcript was widely expressed in a variety of tissues. In situ hybridization of the brain showed expression and localization of the transcript in the hypothalamus, medulla, and olfactory regions, whereas immunohistochemistry using a specific antiserum showed only GnRH-II cell bodies and processes in the preoptic nucleus/hypothalamus areas. Lamprey GnRH-II was shown to stimulate the hypothalamic-pituitary axis using in vivo and in vitro studies. Lamprey GnRH-II was also shown to activate the inositol phosphate signaling system in COS-7 cells transiently transfected with the lamprey GnRH receptor. These studies provide evidence for a novel lamprey GnRH that has a role as a third hypothalamic GnRH. In summary, the newly discovered lamprey GnRH-II offers a new paradigm of the origin of the vertebrate GnRH family. We hypothesize that due to a genome/gene duplication event, an ancestral gene gave rise to two lineages of GnRHs: the gnathostome GnRH and lamprey GnRH-II.

  6. Applications of Qualitative Microanalysis to the Determination of Secondary Species Associated with Uranium

    International Nuclear Information System (INIS)

    Agrinier, H.

    1959-02-01

    Microanalytical techniques are described which allow rapid determinations of secondary species associated with uranium. They consist in exposing the constituent elements of the ores by means of characteristic microchemical reactions. Because of their rapidity and the small amount of apparatus needed, these techniques can be used either in the field or in the laboratory. (author) [fr

  7. Interactions between abiotic filters, landscape structure and species traits as determinants of dairy farmland plant diversity

    NARCIS (Netherlands)

    Lomba, A.; Bunce, R.G.H.; Jongman, R.H.G.; Moreira, F.; Honrado, J.

    2011-01-01

    Maintaining farmland biodiversity in Europe under scenarios of agricultural intensification is a keystone challenge of nature conservation. The recruitment of species from the regional pool to local landscape mosaics and individual patches is known to be determined by multi-scale ecological filters.

  8. 78 FR 55599 - Endangered and Threatened Wildlife and Plants; Determination of Endangered Species Status for...

    Science.gov (United States)

    2013-09-10

    ... occasional fine gold to brassy coloring with stippling dorsally (on the back and sides) and is sooty gray... likely influenced by melting snow and summer monsoon rains. When active above ground, the species is... summer monsoon rains occur. Unfortunately, methods for determining locations to survey salamanders over...

  9. Soil water availability and rooting depth as determinants of hydraulic architecture of Patagonian woody species

    Science.gov (United States)

    Sandra J. Bucci; Fabian G. Scholz; Guillermo Goldstein; Frederick C. Meinzer; Maria E. Arce

    2009-01-01

    We studied the water economy of nine woody species differing in rooting depth in a Patagonian shrub steppe from southern Argentina to understand how soil water availability and rooting depth determine their hydraulic architecture. Soil water content and potentials, leaf water potentials (Leaf) hydraulic conductivity, wood density (Pw), rooting depth, and specific leaf...

  10. Fundamental study on laser manipulation of contamination particles with determining shape, size and species

    International Nuclear Information System (INIS)

    Shimizu, Isao; Fujii, Taketsugu

    1995-01-01

    It has been desired to eliminate or collect the contamination particles of radioisotope in each sort of species or shape and size non-invasively. The shape and size of particle can be determined from the shape and distribution of diffraction pattern of particle in the parallel laser beam, the species of particle can be discriminated by the fluorescence from resonance of laser beam, or by the laser Raman scattering, and the particle suspended in the air or falling down in a vacuum can be levitated against the gravity and trapped by the radiation force and the trapping force of the focussed laser beam in the atmosphere or in a vacuum. For the purpose of the non-invasive manipulation of contamination particles, the laser manipulation technique, image processing technique with Multiplexed Matched Spatial Filter and the determination technique of laser Raman scattering or fluorescence from resonance of laser light were combined in the experiments. The shape, size and species of particles trapped in the focal plane of focused Ar laser beam can be determined simultaneously and instantaneously from the shape and intensity distributions of diffraction patterns of the particles in the irradiation of parallel coherent beam of He-Ne laser, and fluorescence from the resonance of YAG laser beam with variable wave length. In this research, a new technique is proposed to manipulate non-invasively the contamination particles determined with the shape, size and species in the atmosphere or in a vacuum, by laser beam. (author)

  11. Multilevel Empirical Bayes Modeling for Improved Estimation of Toxicant Formulations to Suppress Parasitic Sea Lamprey in the Upper Great Lakes

    Science.gov (United States)

    Hatfield, L.A.; Gutreuter, S.; Boogaard, M.A.; Carlin, B.P.

    2011-01-01

    Estimation of extreme quantal-response statistics, such as the concentration required to kill 99.9% of test subjects (LC99.9), remains a challenge in the presence of multiple covariates and complex study designs. Accurate and precise estimates of the LC99.9 for mixtures of toxicants are critical to ongoing control of a parasitic invasive species, the sea lamprey, in the Laurentian Great Lakes of North America. The toxicity of those chemicals is affected by local and temporal variations in water chemistry, which must be incorporated into the modeling. We develop multilevel empirical Bayes models for data from multiple laboratory studies. Our approach yields more accurate and precise estimation of the LC99.9 compared to alternative models considered. This study demonstrates that properly incorporating hierarchical structure in laboratory data yields better estimates of LC99.9 stream treatment values that are critical to larvae control in the field. In addition, out-of-sample prediction of the results of in situ tests reveals the presence of a latent seasonal effect not manifest in the laboratory studies, suggesting avenues for future study and illustrating the importance of dual consideration of both experimental and observational data. ?? 2011, The International Biometric Society.

  12. A sea lamprey (Petromyzon marinus) sex pheromone mixture increases trap catch relative to a single synthesized component in specific environments

    Science.gov (United States)

    Johnson, Nicholas S.; Tix, John A.; Hlina, Benjamin L.; Wagner, C. Michael; Siefkes, Michael J.; Wang, Huiyong; Li, Weiming

    2015-01-01

    Spermiating male sea lamprey (Petromyzon marinus) release a sex pheromone, of which a component, 7α, 12α, 24-trihydoxy-3-one-5α-cholan-24-sulfate (3kPZS), has been identified and shown to induce long distance preference responses in ovulated females. However, other pheromone components exist, and when 3kPZS alone was used to control invasive sea lamprey populations in the Laurentian Great Lakes, trap catch increase was significant, but gains were generally marginal. We hypothesized that free-ranging sea lamprey populations discriminate between a partial and complete pheromone while migrating to spawning grounds and searching for mates at spawning grounds. As a means to test our hypothesis, and to test two possible uses of sex pheromones for sea lamprey control, we asked whether the full sex pheromone mixture released by males (spermiating male washings; SMW) is more effective than 3kPZS in capturing animals in traditional traps (1) en route to spawning grounds and (2) at spawning grounds. At locations where traps target sea lampreys en route to spawning grounds, SMW-baited traps captured significantly more sea lampreys than paired 3kPZS-baited traps (~10 % increase). At spawning grounds, no difference in trap catch was observed between 3kPZS and SMW-baited traps. The lack of an observed difference at spawning grounds may be attributed to increased pheromone competition and possible involvement of other sensory modalities to locate mates. Because fishes often rely on multiple and sometimes redundant sensory modalities for critical life history events, the addition of sex pheromones to traditionally used traps is not likely to work in all circumstances. In the case of the sea lamprey, sex pheromone application may increase catch when applied to specifically designed traps deployed in streams with low adult density and limited spawning habitat.

  13. Survival and metamorphosis of larval sea lamprey (Petromyzon marinus) residing in Lakes Michigan and Huron near river mouths

    Science.gov (United States)

    Johnson, Nicholas S.; Brenden, Travis O.; Swink, William D.; Lipps, Mathew A.

    2016-01-01

    Although population demographics of larval lampreys in streams have been studied extensively, demographics in lake environments have not. Here, we estimated survival and rates of metamorphosis for larval sea lamprey (Petromyzon marinus) populations residing in the Great Lakes near river mouths (hereafter termed lentic areas). Tagged larvae were stocked and a Bayesian multi-state tag-recovery model was used to investigate population parameters associated with tag recovery, including survival and metamorphosis probabilities. Compared to previous studies of larvae in streams, larval growth in lentic areas was substantially slower (Brody growth coefficient = 0.00132; estimate based on the recovery of six tagged larvae), survival was slightly greater (annual survival = 63%), and the length at which 50% of the larvae would be expected to metamorphose was substantially shorter (126 mm). Stochastic simulations were used to estimate the production of parasitic stage (juvenile) sea lamprey from a hypothetical population of larvae in a lentic environment. Production of juvenile sea lamprey was substantial because, even though larval growth in these environments was slow relative to stream environments, survival was high and length at metamorphosis was less. However, estimated production of juvenile sea lamprey was less for the lentic environment than for similar simulations for river environments where larvae grew faster. In circumstances where the cost to kill a larva with lampricide was equal and control funds are limited, sea lamprey control effort may be best directed toward larvae in streams with fast-growing larvae, because stream-produced larvae will most likely contribute to juvenile sea lamprey populations.

  14. Characterization of a novel bile alcohol sulfate released by sexually mature male sea lamprey (Petromyzon marinus.

    Directory of Open Access Journals (Sweden)

    Ke Li

    Full Text Available A sulphate-conjugated bile alcohol, 3,12-diketo-4,6-petromyzonene-24-sulfate (DKPES, was identified using bioassay-guided fractionation from water conditioned with sexually mature male sea lamprey (Petromyzon marinus. The structure and relative stereochemistry of DKPES was established using spectroscopic data. The electro-olfactogram (EOG response threshold of DKPES was 10(-7 Molar (M and that of 3-keto petromyzonol sulfate (3 KPZS; a known component of the male sea lamprey sex pheromone was 10(-10 M. Behavioural studies indicated that DKPES can be detected at low concentrations by attracting sexually mature females to nests when combined with 3 KPZS. Nests baited with a mixture of DKPES and 3 KPZS (ratio 1∶29.8 attracted equal numbers of sexually mature females compared to an adjacent nest baited with 3 KPZS alone. When DKPES and 3 KPZS mixtures were applied at ratios of 2∶29.8 and 10∶29.8, the proportion of sexually mature females that entered baited nests increased to 73% and 70%, respectively. None of the sexually mature females released were attracted to nests baited with DKPES alone. These results indicated that DKPES is a component of the sex pheromone released by sexually mature male sea lamprey, and is the second biologically active compound identified from this pheromone. DKPES represents the first example that a minor component of a vertebrate pheromone can be combined with a major component to elicit critical sexual behaviors. DKPES holds considerable promise for increasing the effectiveness of pheromone-baited trapping as a means of sea lamprey control in the Laurentian Great Lakes.

  15. An anti-steroidogenic inhibitory primer pheromone in male sea lamprey (Petromyzon marinus)

    Science.gov (United States)

    Chung-Davidson, Yu-Wen; Wang, Huiyong; Bryan, Mara B.; Wu, Hong; Johnson, Nicholas S.; Li, Weiming

    2013-01-01

    Reproductive functions can be modulated by both stimulatory and inhibitory primer pheromones released by conspecifics. Many stimulatory primer pheromones have been documented, but relatively few inhibitory primer pheromones have been reported in vertebrates. The sea lamprey male sex pheromone system presents an advantageous model to explore the stimulatory and inhibitory primer pheromone functions in vertebrates since several pheromone components have been identified. We hypothesized that a candidate sex pheromone component, 7α, 12α-dihydroxy-5α-cholan-3-one-24-oic acid (3 keto-allocholic acid or 3kACA), exerts priming effects through the hypothalamic-pituitary-gonadal (HPG) axis. To test this hypothesis, we measured the peptide concentrations and gene expressions of lamprey gonadotropin releasing hormones (lGnRH) and the HPG output in immature male sea lamprey exposed to waterborne 3kACA. Exposure to waterborne 3kACA altered neuronal activation markers such as jun and jun N-terminal kinase (JNK), and lGnRH mRNA levels in the brain. Waterborne 3kACA also increased lGnRH-III, but not lGnRH-I or -II, in the forebrain. In the plasma, 3kACA exposure decreased all three lGnRH peptide concentrations after 1 h exposure. After 2 h exposure, 3kACA increased lGnRHI and -III, but decreased lGnRH-II peptide concentrations in the plasma. Plasma lGnRH peptide concentrations showed differential phasic patterns. Group housing condition appeared to increase the averaged plasma lGnRH levels in male sea lamprey compared to isolated males. Interestingly, 15α-hydroxyprogesterone (15α-P) concentrations decreased after prolonged 3kACA exposure (at least 24 h). To our knowledge, this is the only known synthetic vertebrate pheromone component that inhibits steroidogenesis in males.

  16. Flexibility in the patterning and control of axial locomotor networks in lamprey.

    Science.gov (United States)

    Buchanan, James T

    2011-12-01

    In lower vertebrates, locomotor burst generators for axial muscles generally produce unitary bursts that alternate between the two sides of the body. In lamprey, a lower vertebrate, locomotor activity in the axial ventral roots of the isolated spinal cord can exhibit flexibility in the timings of bursts to dorsally-located myotomal muscle fibers versus ventrally-located myotomal muscle fibers. These episodes of decreased synchrony can occur spontaneously, especially in the rostral spinal cord where the propagating body waves of swimming originate. Application of serotonin, an endogenous spinal neurotransmitter known to presynaptically inhibit excitatory synapses in lamprey, can promote decreased synchrony of dorsal-ventral bursting. These observations suggest the possible existence of dorsal and ventral locomotor networks with modifiable coupling strength between them. Intracellular recordings of motoneurons during locomotor activity provide some support for this model. Pairs of motoneurons innervating myotomal muscle fibers of similar ipsilateral dorsoventral location tend to have higher correlations of fast synaptic activity during fictive locomotion than do pairs of motoneurons innervating myotomes of different ipsilateral dorsoventral locations, suggesting their control by different populations of premotor interneurons. Further, these different motoneuron pools receive different patterns of excitatory and inhibitory inputs from individual reticulospinal neurons, conveyed in part by different sets of premotor interneurons. Perhaps, then, the locomotor network of the lamprey is not simply a unitary burst generator on each side of the spinal cord that activates all ipsilateral body muscles simultaneously. Instead, the burst generator on each side may comprise at least two coupled burst generators, one controlling motoneurons innervating dorsal body muscles and one controlling motoneurons innervating ventral body muscles. The coupling strength between these two

  17. Evolution of the vertebrate claudin gene family: insights from a basal vertebrate, the sea lamprey.

    Science.gov (United States)

    Mukendi, Christian; Dean, Nicholas; Lala, Rushil; Smith, Jeramiah; Bronner, Marianne E; Nikitina, Natalya V

    2016-01-01

    Claudins are major constituents of tight junctions, contributing both to their intercellular sealing and selective permeability properties. While claudins and claudin-like molecules are present in some invertebrates, the association of claudins with tight junctions has been conclusively documented only in vertebrates. Here we report the sequencing, phylogenetic analysis and comprehensive spatiotemporal expression analysis of the entire claudin gene family in the basal extant vertebrate, the sea lamprey. Our results demonstrate that clear orthologues to about half of all mammalian claudins are present in the lamprey, suggesting that at least one round of whole genome duplication contributed to the diversification of this gene family. Expression analysis revealed that claudins are expressed in discrete and specific domains, many of which represent vertebrate-specific innovations, such as in cranial ectodermal placodes and the neural crest; whereas others represent structures characteristic of chordates, e.g. pronephros, notochord, somites, endostyle and pharyngeal arches. By comparing the embryonic expression of claudins in the lamprey to that of other vertebrates, we found that ancestral expression patterns were often preserved in higher vertebrates. Morpholino mediated loss of Cldn3b demonstrated a functional role for this protein in placode and pharyngeal arch morphogenesis. Taken together, our data provide novel insights into the origins and evolution of the claudin gene family and the significance of claudin proteins in the evolution of vertebrates.

  18. Mixtures of Two Bile Alcohol Sulfates Function as a Proximity Pheromone in Sea Lamprey.

    Directory of Open Access Journals (Sweden)

    Cory O Brant

    Full Text Available Unique mixtures of pheromone components are commonly identified in insects, and have been shown to increase attractiveness towards conspecifics when reconstructed at the natural ratio released by the signaler. In previous field studies of pheromones that attract female sea lamprey (Petromyzon marinus, L., putative components of the male-released mating pheromone included the newly described bile alcohol 3,12-diketo-4,6-petromyzonene-24-sulfate (DkPES and the well characterized 3-keto petromyzonol sulfate (3kPZS. Here, we show chemical evidence that unequivocally confirms the elucidated structure of DkPES, electrophysiological evidence that each component is independently detected by the olfactory epithelium, and behavioral evidence that mature female sea lamprey prefer artificial nests activated with a mixture that reconstructs the male-released component ratio of 30:1 (3kPZS:DkPES, molar:molar. In addition, we characterize search behavior (sinuosity of swim paths of females approaching ratio treatment sources. These results suggest unique pheromone ratios may underlie reproductive isolating mechanisms in vertebrates, as well as provide utility in pheromone-integrated control of invasive sea lamprey in the Great Lakes.

  19. Management strategy evaluation of pheromone-baited trapping techniques to improve management of invasive sea lamprey

    Science.gov (United States)

    Dawson, Heather; Jones, Michael L.; Irwin, Brian J.; Johnson, Nicholas; Wagner, Michael C.; Szymanski, Melissa

    2016-01-01

    We applied a management strategy evaluation (MSE) model to examine the potential cost-effectiveness of using pheromone-baited trapping along with conventional lampricide treatment to manage invasive sea lamprey. Four pheromone-baited trapping strategies were modeled: (1) stream activation wherein pheromone was applied to existing traps to achieve 10−12 mol/L in-stream concentration, (2) stream activation plus two additional traps downstream with pheromone applied at 2.5 mg/hr (reverse-intercept approach), (3) trap activation wherein pheromone was applied at 10 mg/hr to existing traps, and (4) trap activation and reverse-intercept approach. Each new strategy was applied, with remaining funds applied to conventional lampricide control. Simulating deployment of these hybrid strategies on fourteen Lake Michigan streams resulted in increases of 17 and 11% (strategies 1 and 2) and decreases of 4 and 7% (strategies 3 and 4) of the lakewide mean abundance of adult sea lamprey relative to status quo. MSE revealed performance targets for trap efficacy to guide additional research because results indicate that combining lampricides and high efficacy trapping technologies can reduce sea lamprey abundance on average without increasing control costs.

  20. Molecular species composition of plant cardiolipin determined by liquid chromatography mass spectrometry

    Science.gov (United States)

    Zhou, Yonghong; Peisker, Helga

    2016-01-01

    Cardiolipin (CL), an anionic phospholipid of the inner mitochondrial membrane, provides essential functions for stabilizing respiratory complexes and is involved in mitochondrial morphogenesis and programmed cell death in animals. The role of CL and its metabolism in plants are less well understood. The measurement of CL in plants, including its molecular species composition, is hampered by the fact that CL is of extremely low abundance, and that plants contain large amounts of interfering compounds including galactolipids, neutral lipids, and pigments. We used solid phase extraction by anion exchange chromatography to purify CL from crude plant lipid extracts. LC/MS was used to determine the content and molecular species composition of CL. Thus, up to 23 different molecular species of CL were detected in different plant species, including Arabidopsis, mung bean, spinach, barley, and tobacco. Similar to animals, plant CL is dominated by highly unsaturated species, mostly containing linoleic and linolenic acid. During phosphate deprivation or exposure to an extended dark period, the amount of CL decreased in Arabidopsis, accompanied with an increased degree in unsaturation. The mechanism of CL remodeling during stress, and the function of highly unsaturated CL molecular species, remains to be defined. PMID:27179363

  1. Sensitive method for the determination of different S(IV) species in cloud and fog water.

    Science.gov (United States)

    Lammel, G

    1996-08-01

    Suppressed ion chromatography has been applied to the determination of S(IV) species in cloud and fog water in the range 0.012-2.4 mg S(IV)-S/L. The samples have been preserved prior to storage and S(IV) species have been determined as hydroxy methanesulfonate (HMS) together with the low molecular weight carboxylic acid anions, formate and acetate. Samples have been divided and treated differently such that total S(IV) as well as the non-oxidizable fraction of S(IV) (as given by the reactivity with H(2)O(2), added in surplus) could be determined. The difference between the two corresponds to the S(IV) fraction subjected to oxididation, which is of paramount interest in cloud and fogwater chemistry.

  2. Neptunium-237 in the marine environment determination in animal and plant species in the English Channel

    International Nuclear Information System (INIS)

    Germian, P.

    1990-01-01

    The uptake of 237 Np was studied in marine plants and animals belonging to several phyla. Samples were collected from the end of January 1986 to March 1986 in a sampling station near the fuel reprocessing plant at La Hague. 237 Np was determined by neutron activation analysis. The transfer modes of 237 Np to the various species as a function of their trophic levels are discussed as well as the distribution among the organs in the species consumed and the radiological impact of human consumption. (author) 27 refs.; 2 figs.; 1 tab

  3. Separation and determination of arsenic species in water by selective exchange and hybrid resins

    Energy Technology Data Exchange (ETDEWEB)

    Issa, Nureddin Ben [Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, Belgrade (Serbia); Rajakovic-Ognjanovic, Vladana N. [Faculty of Civil Engineering, University of Belgrade, Bulevar Kralja Aleksandra 73, Belgrade (Serbia); Marinkovic, Aleksandar D. [Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, Belgrade (Serbia); Rajakovic, Ljubinka V., E-mail: ljubinka@tmf.bg.ac.rs [Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, Belgrade (Serbia)

    2011-11-07

    Highlights: {yields} A simple and efficient method for separation and determination of arsenic species. {yields} A new hybrid resin HY-AgCl is effective for iAs and oAs analytical separation. {yields} SBAE resin was convenient for the separation of As(III) from As(V) and oAs species. {yields} HY-Fe resin was convenient for the separation of DMAs(V). - Abstract: A simple and efficient method for separation and determination of inorganic arsenic (iAs) and organic arsenic (oAs) in drinking, natural and wastewater was developed. If arsenic is present in water prevailing forms are inorganic acids of As(III) and As(V). oAs can be found in traces as monomethylarsenic acid, MMA(V), and dimethylarsenic acid, DMAs(V). Three types of resins: a strong base anion exchange (SBAE) and two hybrid (HY) resins: HY-Fe and HY-AgCl, based on the activity of hydrated iron oxides and a silver chloride were investigated. It was found that the sorption processes (ion exchange, adsorption and chemisorptions) of arsenic species on SBAE (ion exchange) and HY resins depend on pH values of water. The quantitative separation of molecular and ionic forms of iAs and oAs was achieved by SBAE and pH adjustment, the molecular form of As(III) that exists in the water at pH <8.0 was not bonded with SBAE, which was convenient for direct determination of As(III) concentration in the effluent. HY-Fe resin retained all arsenic species except DMAs(V), which makes possible direct measurements of this specie in the effluent. HY-AgCl resin retained all iAs which was convenient for direct determination of oAs species concentration in the effluent. The selective bonding of arsenic species on three types of resins makes possible the development of the procedure for measuring and calculation of all arsenic species in water. In order to determine capacity of resins the preliminary investigations were performed in batch system and fixed bed flow system. Resin capacities were calculated according to breakthrough

  4. Simultaneous determination of butyltin and phenyltin species in sediments using ultrasound-assisted leaching

    Energy Technology Data Exchange (ETDEWEB)

    Carpinteiro, J.; Rodriguez, I.; Cela, R. [Dpto. Quimica Analitica, Nutricion y Bromatologia, Universidad de Santiago de Compostela (Spain)

    2001-08-01

    A fast and simple procedure is presented for the simultaneous leaching of butyl (mono, di and tributyl) and phenyl organotin species from sediment samples. Leached compounds are further ethylated with sodium tetraethylborate in aqueous medium, and analyzed by gas chromatography. After testing the stability of triphenyltin under different extraction conditions, ultrasound-assisted leaching at room temperature in the presence of acetic acid was been proposed as an extraction procedure compatible with the simultaneous determination of phenyl- and butyltin compounds in sediments. Recoveries between 70 and 90% were obtained for phenyl species in spiked samples prepared in the laboratory. Results for butyltin species were validated by use of the reference material PACS-2. Quantification limits, using GC-MIP-AES as measurement technique, were approximately 5-10 ng g{sup -1}. Precision in the consecutive analysis of three sediment samples varied between 3 and 10%. (orig.)

  5. Effectiveness of scat-detection dogs in determining species presence in a tropical savanna landscape.

    Science.gov (United States)

    Vynne, Carly; Skalski, John R; Machado, Ricardo B; Groom, Martha J; Jácomo, Anah T A; Marinho-Filho, Jader; Ramos Neto, Mario B; Pomilla, Cristina; Silveira, Leandro; Smith, Heath; Wasser, Samuel K

    2011-02-01

    Most protected areas are too small to sustain populations of wide-ranging mammals; thus, identification and conservation of high-quality habitat for those animals outside parks is often a high priority, particularly for regions where extensive land conversion is occurring. This is the case in the vicinity of Emas National Park, a small protected area in the Brazilian Cerrado. Over the last 40 years the native vegetation surrounding the park has been converted to agriculture, but the region still supports virtually all of the animals native to the area. We determined the effectiveness of scat-detection dogs in detecting presence of five species of mammals threatened with extinction by habitat loss: maned wolf (Chrysocyon brachyurus), puma (Puma concolor), jaguar (Panthera onca), giant anteater (Myrmecophaga tridactyla), and giant armadillo (Priodontes maximus). The probability of scat detection varied among the five species and among survey quadrats of different size, but was consistent across team, season, and year. The probability of occurrence, determined from the presence of scat, in a randomly selected site within the study area ranged from 0.14 for jaguars, which occur primarily in the forested areas of the park, to 0.91 for maned wolves, the most widely distributed species in our study area. Most occurrences of giant armadillos in the park were in open grasslands, but in the agricultural matrix they tended to occur in riparian woodlands. At least one target species occurred in every survey quadrat, and giant armadillos, jaguars, and maned wolves were more likely to be present in quadrats located inside than outside the park. The effort required for detection of scats was highest for the two felids. We were able to detect the presence for each of five wide-ranging species inside and outside the park and to assign occurrence probabilities to specific survey sites. Thus, scat dogs provide an effective survey tool for rare species even when accurate detection

  6. Effects of sea lamprey substrate modification and carcass nutrients on macroinvertebrate assemblages in a small Atlantic coastal stream

    Science.gov (United States)

    Weaver, Daniel M.; Coghlan, Stephen M.; Zydlewski, Joseph D.

    2018-01-01

    Aquatic macroinvertebrates respond to patch dynamics arising from interactions of physical and chemical disturbances across space and time. Anadromous fish, such as sea lamprey, Petromyzon marinus, migrate from the ocean and alter physical and chemical properties of recipient spawning streams. Sea lamprey disturb stream benthos physically through nest construction and spawning, and enrich food webs through nutrient deposition from decomposing carcasses. Sea lamprey spawning nests support greater macroinvertebrate abundance than adjacent reference areas, but concurrent effects of stream bed modification and nutrient supplementation have not been examined sequentially. We added carcasses and cleared substrate experimentally to mimic the physical disturbance and nutrient enrichment associated with lamprey spawning, and characterized effects on macroinvertebrate assemblage structure. We found that areas receiving cleared substrate and carcass nutrients were colonized largely by Simuliidae compared to upstream and downstream control areas that were colonized largely by Hydropsychidae, Philopotamidae, and Chironomidae. Environmental factors such as stream flow likely shape assemblages by physically constraining macroinvertebrate establishment and feeding. Our results indicate potential changes in macroinvertebrate assemblages from the physical and chemical changes to streams brought by spawning populations of sea lamprey.

  7. Liquid chromatographic determination of oxytetracycline in edible fish fillets from six species of fish

    Science.gov (United States)

    Meinertz, J.R.; Stehly, G.R.; Gingerich, W.H.

    1998-01-01

    The approved use of oxytetracycline (OTC) in U.S. Aquaculture is limited to specific diseases in salmonids and channel catfish. OTC may also be effective in controlling diseases in other fish species important to public aquaculture, but before approved use of OTC can be augmented, an analytical method for determining OTC in fillet tissue from multiple species of fish will be required to support residue depletion studies. The objective of this study was to develop and validate a liquid chromatographic (LC) method that is accurate, precise, and sensitive for OTC in edible fillets from multiple species of fish. Homogenized fillet tissues from walleye, Atlantic salmon, striped bass, white sturgeon, rainbow trout, and channel catfish were fortified with OTC at nominal concentrations of 10, 20, 100, 1000, and 5000 ng/g. In tissues fortified with OTC at 100, 1000, and 5000 ng/g, mean recoveries ranged from 83 to 90%, and relative standard deviations (RSDs) ranged from 0.9 to 5.8%. In all other tissues, mean recoveries ranged from 59 to 98%, and RSDs ranged from 3.3 to 20%. Method quantitation limits ranged from 6 to 22 ng/g for the 6 species. The LC parameters produced easily integratable OTC peaks without coelution of endogenous compounds. The method is accurate, precise, and sensitive for OTC in fillet tissue from 6 species of fish from 5 phylogenetically diverse groups.

  8. Determining light stress responses for a tropical multi-species seagrass assemblage.

    Science.gov (United States)

    Statton, John; McMahon, Kathryn; Lavery, Paul; Kendrick, Gary A

    2018-03-01

    Existing mitigations to address deterioration in water clarity associated with human activities are based on responses from single seagrass species but may not be appropriate for diverse seagrass assemblages common to tropical waters. We present findings from a light experiment designed to determine the effects of magnitude and duration of low light on a mixed tropical seagrass assemblage. Mixed assemblages of three commonly co-occurring Indo-West Pacific seagrasses, Cymodocea serrulata, Halodule uninervis and Halophila ovalis were grown in climate-controlled tanks, where replicate pots were subjected to a gradient in light availability (0.9-21.6 mols PAR m -2 day -1 ) for 12 weeks. Increased shading resulted in declines in growth and changes in cellular and photosynthesis responses for all species, although time-scale and magnitude of response were species-specific. Applying management criteria (e.g. thresholds) relevant to one species may under- or over-estimate potential for impact on other species and the meadow as a whole. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Environmental switching during biofilm development in a cold seep system and functional determinants of species sorting

    KAUST Repository

    Zhang, Weipeng; Tian, Renmao; Yang, Bo; Cao, Huiluo; Cai, Lin; Chen, Lianguo; Zhou, Guowei; Sun, Jingya; Zhang, Xixiang; Al-Suwailem, Abdulaziz M.; Qian, Pei-Yuan

    2015-01-01

    The functional basis for species sorting theory remains elusive, especially for microbial community assembly in deep sea environments. Using artificial surface-based biofilm models, our recent work revealed taxonomic succession during biofilm development in a newly defined cold seep system, the Thuwal cold seeps II, which comprises a brine pool and the adjacent normal bottom water (NBW) to form a metacommunity via the potential immigration of organisms from one patch to another. Here, we designed an experiment to investigate the effects of environmental switching between the brine pool and the NBW on biofilm assembly, which could reflect environmental filtering effects during bacterial immigration to new environments. Analyses of 16S rRNA genes of 71 biofilm samples suggested that the microbial composition of biofilms established in new environments was determined by both the source community and the incubation conditions. Moreover, a comparison of 18 metagenomes provided evidence for biofilm community assembly that was based primarily on functional features rather than taxonomic identities; metal ion resistance and amino acid metabolism were the major species sorting determinants for the succession of biofilm communities. Genome binning and pathway reconstruction of two bacterial species (Marinobacter sp. and Oleispira sp.) further demonstrated metal ion resistance and amino acid metabolism as functional traits conferring the survival of habitat generalists in both the brine pool and NBW. The results of the present study sheds new light on microbial community assembly in special habitats and bridges a gap in species sorting theory.

  10. Environmental switching during biofilm development in a cold seep system and functional determinants of species sorting.

    Science.gov (United States)

    Zhang, Weipeng; Tian, Renmao; Bo, Yang; Cao, Huiluo; Cai, Lin; Chen, Lianguo; Zhou, Guowei; Sun, Jin; Zhang, Xixiang; Al-Suwailem, Abdulaziz; Qian, Pei-Yuan

    2016-05-01

    The functional basis for species sorting theory remains elusive, especially for microbial community assembly in deep-sea environments. Using artificial surface-based biofilm models, our recent work revealed taxonomic succession during biofilm development in a newly defined cold seep system, the Thuwal cold seeps II, which comprises a brine pool and the adjacent normal bottom water (NBW) to form a metacommunity via the potential immigration of organisms from one patch to another. Here, we designed an experiment to investigate the effects of environmental switching between the brine pool and the NBW on biofilm assembly, which could reflect environmental filtering effects during bacterial immigration to new environments. Analyses of 16S rRNA genes of 71 biofilm samples suggested that the microbial composition of biofilms established in new environments was determined by both the source community and the incubation conditions. Moreover, a comparison of 18 metagenomes provided evidence for biofilm community assembly that was based primarily on functional features rather than taxonomic identities; metal ion resistance and amino acid metabolism were the major species sorting determinants for the succession of biofilm communities. Genome binning and pathway reconstruction of two bacterial species (Marinobacter sp. and Oleispira sp.) further demonstrated metal ion resistance and amino acid metabolism as functional traits conferring the survival of habitat generalists in both the brine pool and NBW. The results of this study shed new light on microbial community assembly in special habitats and bridge a gap in species sorting theory. © 2015 John Wiley & Sons Ltd.

  11. Environmental switching during biofilm development in a cold seep system and functional determinants of species sorting

    KAUST Repository

    Zhang, Weipeng

    2015-11-28

    The functional basis for species sorting theory remains elusive, especially for microbial community assembly in deep sea environments. Using artificial surface-based biofilm models, our recent work revealed taxonomic succession during biofilm development in a newly defined cold seep system, the Thuwal cold seeps II, which comprises a brine pool and the adjacent normal bottom water (NBW) to form a metacommunity via the potential immigration of organisms from one patch to another. Here, we designed an experiment to investigate the effects of environmental switching between the brine pool and the NBW on biofilm assembly, which could reflect environmental filtering effects during bacterial immigration to new environments. Analyses of 16S rRNA genes of 71 biofilm samples suggested that the microbial composition of biofilms established in new environments was determined by both the source community and the incubation conditions. Moreover, a comparison of 18 metagenomes provided evidence for biofilm community assembly that was based primarily on functional features rather than taxonomic identities; metal ion resistance and amino acid metabolism were the major species sorting determinants for the succession of biofilm communities. Genome binning and pathway reconstruction of two bacterial species (Marinobacter sp. and Oleispira sp.) further demonstrated metal ion resistance and amino acid metabolism as functional traits conferring the survival of habitat generalists in both the brine pool and NBW. The results of the present study sheds new light on microbial community assembly in special habitats and bridges a gap in species sorting theory.

  12. Determination of the Geographical Origin of All Commercial Hake Species by Stable Isotope Ratio (SIR) Analysis.

    Science.gov (United States)

    Carrera, Mónica; Gallardo, José M

    2017-02-08

    The determination of the geographical origin of food products is relevant to comply with the legal regulations of traceability, to avoid food fraud, and to guarantee food quality and safety to the consumers. For these reasons, stable isotope ratio (SIR) analysis using an isotope ratio mass spectrometry (IRMS) instrument is one of the most useful techniques for evaluating food traceability and authenticity. The present study was aimed to determine, for the first time, the geographical origin for all commercial fish species belonging to the Merlucciidae family using SIR analysis of carbon (δ 13 C) and nitrogen (δ 15 N). The specific results enabled their clear classification according to the FAO (Food and Agriculture Organization of the United Nations) fishing areas, latitude, and geographical origin in the following six different clusters: European, North African, South African, North American, South American, and Australian hake species.

  13. (macro- Evolutionary ecology of parasite diversity: From determinants of parasite species richness to host diversification

    Directory of Open Access Journals (Sweden)

    Serge Morand

    2015-04-01

    Full Text Available The present review summarized the factors or determinants that may explain parasite diversity among host species and the consequences of this parasite diversity on the evolution of host-life history traits. As host–parasite interactions are asymmetrical exploited–exploiter relationships, ecological and epidemiological theories produce hypotheses to find the potential determinants of parasite species richness, while life-history theory helps for testing potential consequences on parasite diversity on the evolution of hosts. This review referred only to studies that have specifically controlled or took into account phylogenetic information illustrated with parasites of mammals. Several points needing more investigation were identified with a special emphasis to develop the metabolic theory of epidemiology.

  14. Determination of the suitability of certain deciduous species for production of furfural and charcoal

    Energy Technology Data Exchange (ETDEWEB)

    Piotrowski, P.

    1979-01-01

    Determination of the suitability of chips of certain deciduous species for production of furfural and charcoal is discussed. The results of determination of suitability of unpeeled chips from cut branches (beech, birch, alder) and oak chips from wastes of production of furfural and also the suitability of cellolignin obtained from these chips for the production of charcoal are cited. An industrial unit of Swedish make equipped with a continuous hydrolyzer was used in hydrolysis tests of the deciduous chips. Unstripped birch, beech, and alder chips and oak chips from the wastes of wood processing contained 17-20 percent pentozanes and are suitable for industrial production of furfural. The content of substances soluble in an alcohol-benzene mixture in cellolignin from this feedstock was 21.1-30.5 percent. The amount of cellolignin obtained from chips of these species satisfied the demands of charcoal production. The charcoal yield was approximately 20 percent relative to the dry mass of carbonized cellolignin.

  15. Improvement scheme for the determination of arsenic species in mussel and fish tissues

    DEFF Research Database (Denmark)

    Lagarde, F.; Amran, M. B.; Leroy, M. J. F.

    1999-01-01

    Six interlaboratory studies were organised by the Standard, Measurement and Testing Programme of the European Commission on the determination of arsenic species (arsenobetaine, arsenocholine, monomethylarsonic acid, dimethylarsinic acid, As(III) and As(V)) in marine matrices and soil. A step-by-s...... and at the end of the six campaigns allowed the certification of a reference material of tuna-fish tissue (BCR-CRM 627) for its total arsenic, arsenobetaine and dimethylarsinic acid contents....

  16. Plastome Sequence Determination and Comparative Analysis for Members of the Lolium-Festuca Grass Species Complex

    OpenAIRE

    Hand, Melanie L.; Spangenberg, German C.; Forster, John W.; Cogan, Noel O. I.

    2013-01-01

    Chloroplast genome sequences are of broad significance in plant biology, due to frequent use in molecular phylogenetics, comparative genomics, population genetics, and genetic modification studies. The present study used a second-generation sequencing approach to determine and assemble the plastid genomes (plastomes) of four representatives from the agriculturally important Lolium-Festuca species complex of pasture grasses (Lolium multiflorum, Festuca pratensis, Festuca altissima, and Festuca...

  17. Determination of polysaccharide yield from the fruiting bodies and mycelium of selected mushroom species

    International Nuclear Information System (INIS)

    Shaiful Azuar Mohamad; Mat Rasol Awang

    2006-01-01

    Numerous polysaccharides and polysaccharides-protein complexes have been isolated from mushrooms and used as a source of therapeutic agents. The mycelium of Pleurotus sajor caju, Pleurotus tuber-regium, black ganoderma, and the fruiting bodies of Pleurotus sajor caju and Pleurotus florida were used to determine the percentage of polysaccharides obtained from the mushroom raw material. Hot water extraction method was used followed by refrigerated centrifuge and lyophilization. The yield from the various species will be compared. (Author)

  18. Monitoring sea lamprey pheromones and their degradation using rapid stream-side extraction coupled with UPLC-MS/MS

    Science.gov (United States)

    Wang, Huiyong; Johnson, Nicholas; Bernardy, Jeffrey; Hubert, Terry; Li, Weiming

    2013-01-01

    Pheromones guide adult sea lamprey (Petromyzon marinus) to suitable spawning streams and mates, and therefore, when quantified, can be used to assess population size and guide management. Here, we present an efficient sample preparation method where 100 mL of river water was spiked with deuterated pheromone as an internal standard and underwent rapid field-based SPE and elution in the field. The combination of field extraction with laboratory UPLC-MS/MS reduced the sample consumption from 1 to 0.1 L, decreased the sample process time from more than 1 h to 10 min, and increased the precision and accuracy. The sensitivity was improved more than one order of magnitude compared with the previous method. The influences of experimental conditions were assessed to optimize the separation and peak shapes. The analytical method has been validated by studies of stability, selectivity, precision, and linearity and by the determination of the limits of detection and quantification. The method was used to quantify pheromone concentration from five streams tributary to Lake Ontario and to estimate that the environmental half-life of 3kPZS is about 26 h.

  19. Aquatic Nuisance Species Locator

    Science.gov (United States)

    Data in this map has been collected by the United States Geological Survey's Nonindigenous Aquatic Species program located in Gainesville, Florida (http://nas.er.usgs.gov/default.aspx). This dataset may have some inaccuracies and is only current to June 15, 2012. The species identified in this dataset are not inclusive of all aquatic nuisance species, but rather a subset identified to be at risk for transport by recreational activities such as boating and angling. Additionally, the locations where organisims have been identified are also not inclusive and should be treated as a guide. Organisms are limited to the following: American bullfrog, Asian clam, Asian shore crab, Asian tunicate, Australian spotted jellyfish, Chinese mitten crab, New Zealand mudsnail, Colonial sea squirt, Alewife, Bighead carp, Black carp, Flathead catfish, Grass carp, Green crab, Lionfish, Northern snakehead, Quagga mussel, Round Goby, Ruffe, Rusty crayfish, Sea lamprey, Silver carp, Spiny water flea, Veined rapa whelk, Zebra mussel

  20. Energy and speleogenesis: Key determinants of terrestrial species richness in caves.

    Science.gov (United States)

    Jiménez-Valverde, Alberto; Sendra, Alberto; Garay, Policarp; Reboleira, Ana Sofia P S

    2017-12-01

    The aim of this study was to unravel the relative role played by speleogenesis (i.e., the process in which a cave is formed), landscape-scale variables, and geophysical factors in the determination of species richness in caves. Biological inventories from 21 caves located in the southeastern Iberian Peninsula along with partial least square (PLS) regression analysis were used to assess the relative importance of the different explanatory variables. The caves were grouped according to the similarity in their species composition; the effect that spatial distance could have on similarity was also studied using correlation between matrices. The energy and speleogenesis of caves accounted for 44.3% of the variation in species richness. The trophic level of each cave was the most significant factor in PLS regression analysis, and epigenic caves (i.e., those formed by the action of percolating water) had significantly more species than hypogenic ones (i.e., those formed by the action of upward flows in confined aquifers). Dissimilarity among the caves was very high (multiple-site β sim  = 0.92). Two main groups of caves were revealed through the cluster analysis, one formed by the western caves and the other by the eastern ones. The significant-but low-correlation found between faunistic dissimilarity and geographical distance ( r  =   .16) disappeared once the caves were split into the two groups. The extreme beta-diversity suggests a very low connection among the caves and/or a very low dispersal capacity of the species. In the region under study, two main factors are intimately related to the richness of terrestrial subterranean species in caves: the amount of organic material (trophic level) and the formation process (genesis). This is the first time that the history of a cave genesis has been quantitatively considered to assess its importance in explaining richness patterns in comparison with other factors more widely recognized.

  1. High performance liquid chromatography--atomic fluorescence spectrometric determination of arsenic species in beer samples

    International Nuclear Information System (INIS)

    Melo Coelho, N.M.; Parrilla, Carmen; Cervera, M.L.; Pastor, A.; Guardia, M. de la

    2003-01-01

    A method has been developed for the direct determination of As(III), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA) and As(V) in beers by hydride generation--atomic fluorescence spectrometry after separation of arsenic species by high performance liquid chromatography. Compounds were separated by anion-exchange chromatography with isocratic elution using KH 2 PO 4 /K 2 HPO 4 as mobile phase with elution times of 1.67, 2.08, 6.52 and 10.72 min for As(III), DMA, MMA and As(V), respectively. Parameters affecting the hydride generation of all arsenic species were studied and the best conditions were established as a reaction coil of 150 cm, for a sample injected volume of 100 μl, a 4.0% (m/v) solution of sodium tetrahydroborate and 2.0 mol l -1 hydrochloric acid with flow rates of 2.7 and 1.7 ml min -1 , respectively and a flow rate of 500 ml min -1 for the argon carrier gas. Under the best experimental conditions, the detection limit was found to be 0.12, 0.20, 0.27 and 0.39 μg l -1 for As(III), DMA, MMA and As(V), respectively. The relative standard deviation for eight independent determinations varied from 3.9 till 8.9% for species considered at a concentration level of 10.0 μg l -1 . Recovery and comparative studies evidenced that the method is suitable for the accurate determination of arsenic species in water and beer samples

  2. High performance liquid chromatography--atomic fluorescence spectrometric determination of arsenic species in beer samples

    Energy Technology Data Exchange (ETDEWEB)

    Melo Coelho, N.M.; Parrilla, Carmen; Cervera, M.L.; Pastor, A.; Guardia, M. de la

    2003-04-10

    A method has been developed for the direct determination of As(III), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA) and As(V) in beers by hydride generation--atomic fluorescence spectrometry after separation of arsenic species by high performance liquid chromatography. Compounds were separated by anion-exchange chromatography with isocratic elution using KH{sub 2}PO{sub 4}/K{sub 2}HPO{sub 4} as mobile phase with elution times of 1.67, 2.08, 6.52 and 10.72 min for As(III), DMA, MMA and As(V), respectively. Parameters affecting the hydride generation of all arsenic species were studied and the best conditions were established as a reaction coil of 150 cm, for a sample injected volume of 100 {mu}l, a 4.0% (m/v) solution of sodium tetrahydroborate and 2.0 mol l{sup -1} hydrochloric acid with flow rates of 2.7 and 1.7 ml min{sup -1}, respectively and a flow rate of 500 ml min{sup -1} for the argon carrier gas. Under the best experimental conditions, the detection limit was found to be 0.12, 0.20, 0.27 and 0.39 {mu}g l{sup -1} for As(III), DMA, MMA and As(V), respectively. The relative standard deviation for eight independent determinations varied from 3.9 till 8.9% for species considered at a concentration level of 10.0 {mu}g l{sup -1}. Recovery and comparative studies evidenced that the method is suitable for the accurate determination of arsenic species in water and beer samples.

  3. Extraction and determination of arsenic species in leafy vegetables: Method development and application.

    Science.gov (United States)

    Ma, Li; Yang, Zhaoguang; Kong, Qian; Wang, Lin

    2017-02-15

    Extraction of arsenic (As) species in leafy vegetables was investigated by different combinations of methods and extractants. The extracted As species were separated and determined by HPLC-ICP-MS method. The microwave assisted method using 1% HNO3 as the extractant exhibited satisfactory efficiency (>90%) at 90°C for 1.5h. The proposed method was applied for extracting As species from real leafy vegetables. Thirteen cultivars of leafy vegetables were collected and analyzed. The predominant species in all the investigated vegetable samples were As(III) and As(V). Moreover, both As(III) and As(V) concentrations were positive significant (p<0.01) correlated with total As (tAs) concentration. However, the percentage of As(V) reduced with tAs concentration increasing probably due to the conversion and transformation of As(V) to As(III) after uptake. The hazard quotient results indicated no particular risk to 94.6% of local consumers. Considerably carcinogenic risk by consumption of the leafy vegetables was observed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Titanium dioxide solid phase for inorganic species adsorption and determination: the case of arsenic.

    Science.gov (United States)

    Vera, R; Fontàs, C; Anticó, E

    2017-04-01

    We have evaluated a new titanium dioxide (Adsorbsia As600) for the adsorption of both inorganic As (V) and As (III) species. In order to characterize the sorbent, batch experiments were undertaken to determine the capacities of As (III) and As (V) at pH 7.3, which were found to be 0.21 and 0.14 mmol g -1 , respectively. Elution of adsorbed species was only possible using basic solutions, and arsenic desorbed under batch conditions was 50 % when 60 mg of loaded titanium dioxide was treated with 0.5 M NaOH solution. Moreover, its use as a sorbent for solid-phase extraction and preconcentration of arsenic species from well waters has been investigated, without any previous pretreatment of the sample. Solid-phase extraction was implemented by packing several minicolumns with Adsorbsia As600. The method has been validated showing good accuracy and precision. Acceptable recoveries were obtained when spiked waters at 100-200 μg L -1 were measured. The presence of major anions commonly found in waters did not affect arsenic adsoption, and only silicate at 100 mg L -1 level severely competed with arsenic species to bind to the material. Finally, the measured concentrations in water samples containing arsenic from the Pyrinees (Catalonia, Spain) showed good agreement with the ICP-MS results.

  5. Individual Phosphatidylcholine Species Analysis by RP-HPLC-ELSD for Determination of Polyenylphosphatidylcholine in Lecithins.

    Science.gov (United States)

    Lee, Wei-Ju; Weng, Shun-Hsiang; Su, Nan-Wei

    2015-04-22

    Polyenylphosphatidylcholine (PPC), a subgroup of the bioactive agents in phosphatidylcholine (PC), has been indicated to possess liver-protective effects. This study aimed to investigate a promising and feasible method to determine PC molecular species with a reverse phase (RP) high-performance liquid chromatograph (HPLC) equipped with an evaporative light scattering detector (ELSD). Chromatography was achieved using a C30 column and an isocratic mobile phase consisting of acetonitrile/methanol/triethylamine (40/58/2, v/v/v) at a flow rate of 1 mL/min, and ELSD detection was performed using 80 °C for the drift tube and an air flow rate of 1.8 L/min. To identify individual peaks on the chromatogram, MALDI-TOF-MS was employed for initial detection, and then the results were used to investigate the relationship between the retention time and fatty acyl chains of each PC molecule. A linear correlation was observed between the retention time and theoretical carbon number (TCN) of individual PC species. The compositions of PC molecular species in soybean and sunflower lecithins were similar to each other, and the major PC molecular species were 1,2-dilinoleoyl-sn-glycero-3-phosphocholine (LLPC), 1-oleoyl-2-linoleoyl-sn-glycero-3-phosphocholine (OLPC), and 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine (PLPC). The contents of LLPC in soybean PC and sunflower PC were 40.6% and 64.3%, respectively.

  6. Determination of dose ranges of gamma rays to induce specific changes in three ornamental species

    International Nuclear Information System (INIS)

    Gonzalez J, J.

    2011-11-01

    In order to confirming the possibility of to settle a dose range that takes place directly and not at random, a specific effect independently of the species that is were produced several similar organisms to three ornamental species took place via meristems cultivation: Petunia hybrid, Impatiens walleriana and Sprekelia formosissima, same that were irradiated in an irradiator Gamma cell 220, to different dose: 0, 3.5, 5.0, 7.5, 10, 12.5, 15, 17.5 and 20 Gy. Later on, of the plants treated via in vitro the subsequent generations were obtained until the M 4 . To determine the DL 50 and the possible good doses, the survival parameters, development, morphogenesis and height were evaluated during 8 weeks, interpreting based on them, the possible physiologic and genetic alterations induced by the radiation. The established DL 50 were: 7.5 Gy (Petunia), 19.0 Gy (Impatiens) and 12.0 Gy (Sprekelia). Based on the DL 50 of each species, a range of coincident dose settled down that produces a similar effect in the three species: a range of DL 23 to the DL 50 induces and alteration in the cytokinins production affecting directly in the leaves number, buds and plants taken place by meristem, also a range of DL 32 - DL 50 impacts in the auxins production altering to the radicule system. However, when being superimposed the dose is considered that the investigation should continue. (Author)

  7. Determination of trace metals and analysis of arsenic species in tropical marine fishes from Spratly islands.

    Science.gov (United States)

    Li, Jingxi; Sun, Chengjun; Zheng, Li; Jiang, Fenghua; Wang, Shuai; Zhuang, Zhixia; Wang, Xiaoru

    2017-09-15

    Trace metal contents in 38 species of tropical marine fishes harvested from the Spratly islands of China were determined by microwave digestion and inductively coupled plasma mass spectrometry analysis. Arsenic species were determined by high-performance liquid chromatography and inductively coupled plasma mass spectrometry analysis. The average levels of Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Pb, and U in the fish samples were 1.683, 0.350, 0.367, 2.954, 36.615, 0.087, 0.319, 1.566, 21.946, 20.845, 2.526, 3.583, 0.225, 0.140, and 0.061mg·kg -1 , respectively; Fe, Zn, and As were found at high concentrations. The trace metals exhibited significant positive correlation between each other, with r value of 0.610-0.852. Further analysis indicated that AsB (8.560-31.020mg·kg -1 ) was the dominant arsenic species in the fish samples and accounted for 31.48% to 47.24% of the total arsenic. As(III) and As(V) were detected at low concentrations, indicating minimal arsenic toxicity. Copyright © 2017. Published by Elsevier Ltd.

  8. Determination of the soil hazardous concentrations of bisphenol A using the species sensitivity approach.

    Science.gov (United States)

    Kwak, Jin Il; Moon, Jongmin; Kim, Dokyung; Cui, Rongxue; An, Youn-Joo

    2018-02-15

    This study describes the determination of the species sensitivity distribution (SSD)-based soil hazardous contamination of bisphenol A for environmental risk assessment. We conducted a battery of bioassays, including acute assays using eight species from six different taxonomic groups and chronic assays using five species from four different taxonomic groups. We determined that our dataset satisfied Australia & New Zealand's guidelines for applying the SSD methodology. Finally, the chronic soil HC 5 and HC 50 values for bisphenol A were estimated to be 13.7 and 74.7mg/kg soil, respectively, for soil ecosystem protection against chronic exposure using the data generated from this and previous studies. Because the soil standard values of bisphenol A for protection of the soil ecosystem are not currently available, the HC values of bisphenol A that we suggested based on the SSD approach would be applied as fundamental data to establish soil standards of bisphenol A for soil ecosystem protection. To our knowledge, this is the first study reporting the soil hazardous concentration of bisphenol A for environmental risk assessment. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Antimicrobial resistance and resistance gene determinants in clinical Escherichia coli from different animal species in Switzerland.

    Science.gov (United States)

    Lanz, Roland; Kuhnert, Peter; Boerlin, Patrick

    2003-01-02

    Antimicrobial susceptibility testing was performed on a total of 581 clinical Escherichia coli isolates from diarrhea and edema disease in pigs, from acute mastitis in dairy cattle, from urinary tract infections in dogs and cats, and from septicemia in laying hens collected in Switzerland between 1999 and 2001. Among the 16 antimicrobial agents tested, resistance was most frequent for sulfonamides, tetracycline, and streptomycin. Isolates from swine presented significantly more resistance than those from the other animal species. The distribution of the resistance determinants for sulfonamides, tetracycline, and streptomycin was assessed by hybridization and PCR in resistant isolates. Significant differences in the distribution of resistance determinants for tetracycline (tetA, tetB) and sulfonamides (sulII) were observed between the isolates from swine and those from the other species. Resistance to sulfonamides could not be explained by known resistance mechanisms in more than a quarter of the sulfonamide-resistant and sulfonamide-intermediate isolates from swine, dogs and cats. This finding suggests that one or several new resistance mechanisms for sulfonamides may be widespread among E. coli isolates from these animal species. The integrase gene (intI) from class I integrons was detected in a large proportion of resistant isolates in association with the sulI and aadA genes, thus demonstrating the importance of integrons in the epidemiology of resistance in clinical E. coli isolates from animals.

  10. Reflectance-based determination of age and species of blowfly puparia.

    Science.gov (United States)

    Voss, Sasha C; Magni, Paola; Dadour, Ian; Nansen, Christian

    2017-01-01

    Forensic entomology is primarily concerned with the estimation of time since death and involves determination of the age of immature insects colonising decomposing remains. Accurate age determination of puparia is usually accomplished by dissection, which means destructive sampling of evidence. As part of improving abilities to correctly identify species and developmental age, it is highly desirable to have available non-destructive methods. In this study, we acquired external hyperspectral imaging (HSI) data (77 spectral bands, 389-892 nm) from the dorsal and ventral sides of individual puparia of two species of blowfly (Diptera: Calliphoridae), Calliphora dubia Macquart 1855 and Chrysomya rufifacies Macquart 1842. Puparia were dissected to determine the presence/absence of eight internal morphological development characteristics (legs, wings, labella, abdominal segments, antennae, thoracic bristles, orbital/facial bristles and eye colour and arista). Based on linear discriminant analysis and independent validation of HSI data, reflectance features from puparia could be used to successfully (1) distinguish the two species (classification accuracy = 92.5 %), (2) differentiate dorsal and ventral sides of puparia (classification accuracy C. dubia = 81.5 %; Ch. rufifacies = 89.2 %) and (3) predict the presence of these morphological characteristics and therefore the developmental stage of puparia (average classification accuracy using dorsal imaging: C. dubia = 90.3 %; Ch. rufifacies = 94.0 %). The analytical approach presented here provides proof of concept for a direct puparial age relationship (i.e. days since the onset of pupation) between external puparial reflectance features and internal morphological development. Furthermore, this approach establishes the potential for further refinement by using a non-invasive technique to determine the age and developmental stage of blowflies of forensic importance.

  11. Determination of chromium, mercury, selenium and zinc in marine fish species of Malaysia

    International Nuclear Information System (INIS)

    Nazaratul Ashifa Abdullah Salim; Wee, B.S.; Ezwiza Sanuri; Mohd Suhaimi Hamzah; Mohd Suhaimi Elias, Shamsiah Abdul Rahman; Azian Hashim

    2013-01-01

    Full-text: Concentrations of chromium, mercury, selenium and zinc were determined in eight commonly edible marine fish species; mackerel, red snapper, thread fin, tuna, hard tail scads, val, doubled spotted queen fish and shark. This study was based on market basket method were those species were collected from two locations of Kuala Selangor and Kuala Terengganu. All elements were measured using instrumental neutron activation analysis (INAA) technique. The accuracy and precision analysis were checked by analyzing Certified Reference Material (CRM) namely DORM-3 and MAA-2. Elements of interest in the edible parts of the investigated fish were mostly in the permissible safety levels for human consumption based on national and international safety guideline except for mercury where some fishes showed slightly higher concentrations than the guidelines. (author)

  12. Microarray-based whole-genome hybridization as a tool for determining procaryotic species relatedness

    Energy Technology Data Exchange (ETDEWEB)

    Wu, L.; Liu, X.; Fields, M.W.; Thompson, D.K.; Bagwell, C.E.; Tiedje, J. M.; Hazen, T.C.; Zhou, J.

    2008-01-15

    The definition and delineation of microbial species are of great importance and challenge due to the extent of evolution and diversity. Whole-genome DNA-DNA hybridization is the cornerstone for defining procaryotic species relatedness, but obtaining pairwise DNA-DNA reassociation values for a comprehensive phylogenetic analysis of procaryotes is tedious and time consuming. A previously described microarray format containing whole-genomic DNA (the community genome array or CGA) was rigorously evaluated as a high-throughput alternative to the traditional DNA-DNA reassociation approach for delineating procaryotic species relationships. DNA similarities for multiple bacterial strains obtained with the CGA-based hybridization were comparable to those obtained with various traditional whole-genome hybridization methods (r=0.87, P<0.01). Significant linear relationships were also observed between the CGA-based genome similarities and those derived from small subunit (SSU) rRNA gene sequences (r=0.79, P<0.0001), gyrB sequences (r=0.95, P<0.0001) or REP- and BOX-PCR fingerprinting profiles (r=0.82, P<0.0001). The CGA hybridization-revealed species relationships in several representative genera, including Pseudomonas, Azoarcus and Shewanella, were largely congruent with previous classifications based on various conventional whole-genome DNA-DNA reassociation, SSU rRNA and/or gyrB analyses. These results suggest that CGA-based DNA-DNA hybridization could serve as a powerful, high-throughput format for determining species relatedness among microorganisms.

  13. Climate and soil attributes determine plant species turnover in global drylands

    Science.gov (United States)

    Maestre, Fernando T.; Gotelli, Nicholas J.; Quero, José L.; Delgado-Baquerizo, Manuel; Bowker, Matthew A.; Eldridge, David J.; Ochoa, Victoria; Gozalo, Beatriz; Valencia, Enrique; Berdugo, Miguel; Escolar, Cristina; García-Gómez, Miguel; Escudero, Adrián; Prina, Aníbal; Alfonso, Graciela; Arredondo, Tulio; Bran, Donaldo; Cabrera, Omar; Cea, Alex; Chaieb, Mohamed; Contreras, Jorge; Derak, Mchich; Espinosa, Carlos I.; Florentino, Adriana; Gaitán, Juan; Muro, Victoria García; Ghiloufi, Wahida; Gómez-González, Susana; Gutiérrez, Julio R.; Hernández, Rosa M.; Huber-Sannwald, Elisabeth; Jankju, Mohammad; Mau, Rebecca L.; Hughes, Frederic Mendes; Miriti, Maria; Monerris, Jorge; Muchane, Muchai; Naseri, Kamal; Pucheta, Eduardo; Ramírez-Collantes, David A.; Raveh, Eran; Romão, Roberto L.; Torres-Díaz, Cristian; Val, James; Veiga, José Pablo; Wang, Deli; Yuan, Xia; Zaady, Eli

    2015-01-01

    Aim Geographic, climatic, and soil factors are major drivers of plant beta diversity, but their importance for dryland plant communities is poorly known. This study aims to: i) characterize patterns of beta diversity in global drylands, ii) detect common environmental drivers of beta diversity, and iii) test for thresholds in environmental conditions driving potential shifts in plant species composition. Location 224 sites in diverse dryland plant communities from 22 geographical regions in six continents. Methods Beta diversity was quantified with four complementary measures: the percentage of singletons (species occurring at only one site), Whittake’s beta diversity (β(W)), a directional beta diversity metric based on the correlation in species occurrences among spatially contiguous sites (β(R2)), and a multivariate abundance-based metric (β(MV)). We used linear modelling to quantify the relationships between these metrics of beta diversity and geographic, climatic, and soil variables. Results Soil fertility and variability in temperature and rainfall, and to a lesser extent latitude, were the most important environmental predictors of beta diversity. Metrics related to species identity (percentage of singletons and β(W)) were most sensitive to soil fertility, whereas those metrics related to environmental gradients and abundance ((β(R2)) and β(MV)) were more associated with climate variability. Interactions among soil variables, climatic factors, and plant cover were not important determinants of beta diversity. Sites receiving less than 178 mm of annual rainfall differed sharply in species composition from more mesic sites (> 200 mm). Main conclusions Soil fertility and variability in temperature and rainfall are the most important environmental predictors of variation in plant beta diversity in global drylands. Our results suggest that those sites annually receiving ~ 178 mm of rainfall will be especially sensitive to future climate changes. These

  14. Climate and soil attributes determine plant species turnover in global drylands.

    Science.gov (United States)

    Ulrich, Werner; Soliveres, Santiago; Maestre, Fernando T; Gotelli, Nicholas J; Quero, José L; Delgado-Baquerizo, Manuel; Bowker, Matthew A; Eldridge, David J; Ochoa, Victoria; Gozalo, Beatriz; Valencia, Enrique; Berdugo, Miguel; Escolar, Cristina; García-Gómez, Miguel; Escudero, Adrián; Prina, Aníbal; Alfonso, Graciela; Arredondo, Tulio; Bran, Donaldo; Cabrera, Omar; Cea, Alex; Chaieb, Mohamed; Contreras, Jorge; Derak, Mchich; Espinosa, Carlos I; Florentino, Adriana; Gaitán, Juan; Muro, Victoria García; Ghiloufi, Wahida; Gómez-González, Susana; Gutiérrez, Julio R; Hernández, Rosa M; Huber-Sannwald, Elisabeth; Jankju, Mohammad; Mau, Rebecca L; Hughes, Frederic Mendes; Miriti, Maria; Monerris, Jorge; Muchane, Muchai; Naseri, Kamal; Pucheta, Eduardo; Ramírez-Collantes, David A; Raveh, Eran; Romão, Roberto L; Torres-Díaz, Cristian; Val, James; Veiga, José Pablo; Wang, Deli; Yuan, Xia; Zaady, Eli

    2014-12-01

    Geographic, climatic, and soil factors are major drivers of plant beta diversity, but their importance for dryland plant communities is poorly known. This study aims to: i) characterize patterns of beta diversity in global drylands, ii) detect common environmental drivers of beta diversity, and iii) test for thresholds in environmental conditions driving potential shifts in plant species composition. 224 sites in diverse dryland plant communities from 22 geographical regions in six continents. Beta diversity was quantified with four complementary measures: the percentage of singletons (species occurring at only one site), Whittake's beta diversity (β(W)), a directional beta diversity metric based on the correlation in species occurrences among spatially contiguous sites (β(R 2 )), and a multivariate abundance-based metric (β(MV)). We used linear modelling to quantify the relationships between these metrics of beta diversity and geographic, climatic, and soil variables. Soil fertility and variability in temperature and rainfall, and to a lesser extent latitude, were the most important environmental predictors of beta diversity. Metrics related to species identity (percentage of singletons and β(W)) were most sensitive to soil fertility, whereas those metrics related to environmental gradients and abundance ((β(R 2 )) and β(MV)) were more associated with climate variability. Interactions among soil variables, climatic factors, and plant cover were not important determinants of beta diversity. Sites receiving less than 178 mm of annual rainfall differed sharply in species composition from more mesic sites (> 200 mm). Soil fertility and variability in temperature and rainfall are the most important environmental predictors of variation in plant beta diversity in global drylands. Our results suggest that those sites annually receiving ~ 178 mm of rainfall will be especially sensitive to future climate changes. These findings may help to define appropriate

  15. Determination of atmospheric iodine species using a system of specifically prepared filters and IDMS

    International Nuclear Information System (INIS)

    Gaebler, H.E.; Heumann, K.G.

    1993-01-01

    A system was developed which allowed the determination of four different atmospheric iodine species by preparing glass microfibre filters, which were arranged in consecutive order, in a specific way. Particulate iodine was collected by a particle filter, HI and I 2 by a NaOH impregnated filter, HOI was adsorbed on a TBAH impregnated filter and organoiodine was adsorbed on a filter loaded with activated charcoal. These behaviours were checked by extensive model experiments. Two or more filters of the same type were used in series to show the degree of collection of one iodine species. Two European samples, one of continental and one of marine origin, and two Antarctic samples were analysed by this filter system using isotope dilution mass spectrometry (IDMS) for quantification. The distribution pattern for the different iodine species is similar for the two European samples. Organoiodine is found to be the most abundant species whereas in Antarctica the HI/I 2 fraction is up to nearly 50% of the total iodine. The particulate iodine fraction is higher in Europe than in Antarctica, which is due to the low particle concentration in the remote area of Antarctica. The higher HI/I 2 and HOI fractions found at the North Sea compared with the continental sample indicate that the ocean is a primary source of these species. Concentrations in the range of (0.3-3.1) ngI/m 3 were analysed for particulate iodine, (0.4-1.3) ng I/m 3 for HI/I 2 , (0.2-1.8) ng I/m 3 for HOI and (0.4-7.6) ng I/m 3 for organoiodine. The detection limits varied with the variances of the blank values of the different filters and lay between 0.02 ng I/m 3 and 0.24 ng I/m 3 using sample volumes of 70 m 3 air. (orig.)

  16. Plant Size as Determinant of Species Richness of Herbivores, Natural Enemies and Pollinators across 21 Brassicaceae Species.

    Directory of Open Access Journals (Sweden)

    Hella Schlinkert

    Full Text Available Large plants are often more conspicuous and more attractive for associated animals than small plants, e.g. due to their wider range of resources. Therefore, plant size can positively affect species richness of associated animals, as shown for single groups of herbivores, but studies usually consider intraspecific size differences of plants in unstandardised environments. As comprehensive tests of interspecific plant size differences under standardised conditions are missing so far, we investigated effects of plant size on species richness of all associated arthropods using a common garden experiment with 21 Brassicaceae species covering a broad interspecific plant size gradient from 10 to 130 cm height. We recorded plant associated ecto- and endophagous herbivores, their natural enemies and pollinators on and in each aboveground plant organ, i.e. flowers, fruits, leaves and stems. Plant size (measured as height from the ground, the number of different plant organ entities and their biomass were assessed. Increasing plant size led to increased species richness of associated herbivores, natural enemies and pollinating insects. This pattern was found for ectophagous and endophagous herbivores, their natural enemies, as well as for herbivores associated with leaves and fruits and their natural enemies, independently of the additional positive effects of resource availability (i.e. organ biomass or number of entities and, regarding natural enemies, herbivore species richness. We found a lower R2 for pollinators compared to herbivores and natural enemies, probably caused by the high importance of flower characteristics for pollinator species richness besides plant size. Overall, the increase in plant height from 10 to 130 cm led to a 2.7-fold increase in predicted total arthropod species richness. In conclusion, plant size is a comprehensive driver of species richness of the plant associated arthropods, including pollinators, herbivores and their

  17. Diagnostic sensitivity of ultrasound, radiography and computed tomography for gender determination in four species of lizards.

    Science.gov (United States)

    Di Ianni, Francesco; Volta, Antonella; Pelizzone, Igor; Manfredi, Sabrina; Gnudi, Giacomo; Parmigiani, Enrico

    2015-01-01

    Gender determination is frequently requested by reptile breeders, especially for species with poor or absent sexual dimorphism. The aims of the current study were to describe techniques and diagnostic sensitivities of ultrasound, radiography, and computed tomography for gender determination (identification of hemipenes) in four species of lizards. Nineteen lizards of known sex, belonging to four different species (Pogona vitticeps, Uromastyx aegyptia, Tiliqua scincoides, Gerrhosaurus major) were prospectively enrolled. With informed owner consent, ultrasound, noncontrast CT, contrast radiography, and contrast CT (with contrast medium administered into the cloaca) were performed in conscious animals. Imaging studies were reviewed by three different operators, each unaware of the gender of the animals and of the results of the other techniques. The lizard was classified as a male when hemipenes were identified. Nineteen lizards were included in the study, 10 females and nine males. The hemipenes were seen on ultrasound in only two male lizards, and appeared as oval hypoechoic structures. Radiographically, hemipenes filled with contrast medium appeared as spindle-shaped opacities. Noncontrast CT identified hemipenes in only two lizards, and these appeared as spindle-shaped kinked structures with hyperattenuating content consistent with smegma. Hemipenes were correctly identified in all nine males using contrast CT (accuracy of 100%). Accuracy of contrast radiography was excellent (94.7%). Accuracy of ultrasound and of noncontrast CT was poor (64.3% and 63.1%, respectively). Findings from the current study supported the use of contrast CT or contrast radiography for gender determination in lizards. © 2014 American College of Veterinary Radiology.

  18. Lamprey Prohibitin2 Arrest G2/M Phase Transition of HeLa Cells through Down-regulating Expression and Phosphorylation Level of Cell Cycle Proteins.

    Science.gov (United States)

    Shi, Ying; Guo, Sicheng; Wang, Ying; Liu, Xin; Li, Qingwei; Li, Tiesong

    2018-03-02

    Prohibitin 2(PHB2) is a member of the SFPH trans-membrane family proteins. It is a highly conserved and functionally diverse protein that plays an important role in preserving the structure and function of the mitochondria. In this study, the lamprey PHB2 gene was expressed in HeLa cells to investigate its effect on cell proliferation. The effect of Lm-PHB2 on the proliferation of HeLa cells was determined by treating the cells with pure Lm-PHB2 protein followed by MTT assay. Using the synchronization method with APC-BrdU and PI double staining revealed rLm-PHB2 treatment induced the decrease of both S phase and G0/G1 phase and then increase of G2/M phase. Similarly, cells transfected with pEGFP-N1-Lm-PHB2 also exhibited remarkable reduction in proliferation. Western blot and quantitative real-time PCR(qRT-PCR) assays suggested that Lm-PHB2 caused cell cycle arrest in HeLa cells through inhibition of CDC25C and CCNB1 expression. According to our western blot analysis, Lm-PHB2 was also found to reduce the expression level of Wee1 and PLK1 and the phosphorylation level of CCNB1, CDC25C and CDK1 in HeLa cells. Lamprey prohibitin 2 could arrest G2/M phase transition of HeLa cells through down-regulating expression and phosphorylation level of cell cycle proteins.

  19. Genetic models reveal historical patterns of sea lamprey population fluctuations within Lake Champlain

    Directory of Open Access Journals (Sweden)

    Cassidy C. D’Aloia

    2015-10-01

    Full Text Available The origin of sea lamprey (Petromyzon marinus in Lake Champlain has been heavily debated over the past decade. Given the lack of historical documentation, two competing hypotheses have emerged in the literature. First, it has been argued that the relatively recent population size increase and concomitant rise in wounding rates on prey populations are indicative of an invasive population that entered the lake through the Champlain Canal. Second, recent genetic evidence suggests a post-glacial colonization at the end of the Pleistocene, approximately 11,000 years ago. One limitation to resolving the origin of sea lamprey in Lake Champlain is a lack of historical and current measures of population size. In this study, the issue of population size was explicitly addressed using nuclear (nDNA and mitochondrial DNA (mtDNA markers to estimate historical demography with genetic models. Haplotype network analysis, mismatch analysis, and summary statistics based on mtDNA noncoding sequences for NCI (479 bp and NCII (173 bp all indicate a recent population expansion. Coalescent models based on mtDNA and nDNA identified two potential demographic events: a population decline followed by a very recent population expansion. The decline in effective population size may correlate with land-use and fishing pressure changes post-European settlement, while the recent expansion may be associated with the implementation of the salmonid stocking program in the 1970s. These results are most consistent with the hypothesis that sea lamprey are native to Lake Champlain; however, the credibility intervals around parameter estimates demonstrate that there is uncertainty regarding the magnitude and timing of past demographic events.

  20. The sterile-male-release technique in Great Lakes sea lamprey management

    Science.gov (United States)

    Twohey, Michael B.; Heinrich, John W.; Seelye, James G.; Fredricks, Kim T.; Bergstedt, Roger A.; Kaye, Cheryl A.; Scholefield, Ron J.; McDonald, Rodney B.; Christie, Gavin C.

    2003-01-01

    The implementation of a sterile-male-release technique from 1991 through 1999 and evaluation of its effectiveness in the Great Lakes sea lamprey (Petromyzon marinus) management program is reviewed. Male sea lampreys were injected with the chemosterilant bisazir (P,P-bis(1-aziridinyl)-N-methylphosphinothioic amide) using a robotic device. Quality assurance testing indicated the device delivered a consistent and effective dose of bisazir. Viability of embryos in an untreated control group was 64% compared to 1% in a treatment group. A task force developed nine hypotheses to guide implementation and evaluation of the technique. An annual average of 26,000 male sea lampreys was harvested from as many as 17 Great Lakes tributaries for use in the technique. An annual average of 16,100 sterilized males was released into 33 tributaries of Lake Superior to achieve a theoretical 59% reduction in larval production during 1991 to 1996. The average number of sterile males released in the St. Marys River increased from 4,000 during 1991 to 1996 to 20,100 during 1997 to 1999. The theoretical reduc-stertion in reproduction when combined with trapping was 57% during 1991 to 1996 and 86% during 1997 to 1999. Evaluation studies demonstrated that sterilized males were competitive and reduced production of larvae in streams. Field studies and simulation models suggest reductions in reproduction will result in fewer recruits, but there is risk of periodic high recruitment events independent of sterile-male release. Strategies to reduce reproduction will be most reliable when low densities of reproducing females are achieved. Expansion of the technique is limited by access to additional males for sterilization. Sterile-male release and other alternative controls are important in delivering integrated pest management and in reducing reliance on pesticides.

  1. Lamins of the sea lamprey (Petromyzon marinus) and the evolution of the vertebrate lamin protein family.

    Science.gov (United States)

    Schilf, Paul; Peter, Annette; Hurek, Thomas; Stick, Reimer

    2014-07-01

    Lamin proteins are found in all metazoans. Most non-vertebrate genomes including those of the closest relatives of vertebrates, the cephalochordates and tunicates, encode only a single lamin. In teleosts and tetrapods the number of lamin genes has quadrupled. They can be divided into four sub-types, lmnb1, lmnb2, LIII, and lmna, each characterized by particular features and functional differentiations. Little is known when during vertebrate evolution these features have emerged. Lampreys belong to the Agnatha, the sister group of the Gnathostomata. They split off first within the vertebrate lineage. Analysis of the sea lamprey (Petromyzon marinus) lamin complement presented here, identified three functional lamin genes, one encoding a lamin LIII, indicating that the characteristic gene structure of this subtype had been established prior to the agnathan/gnathostome split. Two other genes encode lamins for which orthology to gnathostome lamins cannot be designated. Search for lamin gene sequences in all vertebrate taxa for which sufficient sequence data are available reveals the evolutionary time frame in which specific features of the vertebrate lamins were established. Structural features characteristic for A-type lamins are not found in the lamprey genome. In contrast, lmna genes are present in all gnathostome lineages suggesting that this gene evolved with the emergence of the gnathostomes. The analysis of lamin gene neighborhoods reveals noticeable similarities between the different vertebrate lamin genes supporting the hypothesis that they emerged due to two rounds of whole genome duplication and makes clear that an orthologous relationship between a particular vertebrate paralog and lamins outside the vertebrate lineage cannot be established. Copyright © 2014 Elsevier GmbH. All rights reserved.

  2. Retinal amino acid neurochemistry of the southern hemisphere lamprey, Geotria australis.

    Directory of Open Access Journals (Sweden)

    Lisa Nivison-Smith

    Full Text Available Lampreys are one of the two surviving groups of the agnathan (jawless stages in vertebrate evolution and are thus ideal candidates for elucidating the evolution of visual systems. This study investigated the retinal amino acid neurochemistry of the southern hemisphere lamprey Geotria australis during the downstream migration of the young, recently-metamorphosed juveniles to the sea and during the upstream migration of the fully-grown and sexually-maturing adults to their spawning areas. Glutamate and taurine were distributed throughout the retina, whilst GABA and glycine were confined to neurons of the inner retina matching patterns seen in most other vertebrates. Glutamine and aspartate immunoreactivity was closely matched to Müller cell morphology. Between the migratory phases, few differences were observed in the distribution of major neurotransmitters i.e. glutamate, GABA and glycine, but changes in amino acids associated with retinal metabolism i.e. glutamine and aspartate, were evident. Taurine immunoreactivity was mostly conserved between migrant stages, consistent with its role in primary cell functions such as osmoregulation. Further investigation of glutamate signalling using the probe agmatine (AGB to map cation channel permeability revealed entry of AGB into photoreceptors and horizontal cells followed by accumulation in inner retinal neurons. Similarities in AGB profiles between upstream and downstream migrant of G. australis confirmed the conservation of glutamate neurotransmission. Finally, calcium binding proteins, calbindin and calretinin were localized to the inner retina whilst recoverin was localized to photoreceptors. Overall, conservation of major amino acid neurotransmitters and calcium-associated proteins in the lamprey retina confirms these elements as essential features of the vertebrate visual system. On the other hand, metabolic elements of the retina such as neurotransmitter precursor amino acids and Müller cells

  3. DetOx: a program for determining anomalous scattering factors of mixed-oxidation-state species.

    Science.gov (United States)

    Sutton, Karim J; Barnett, Sarah A; Christensen, Kirsten E; Nowell, Harriott; Thompson, Amber L; Allan, David R; Cooper, Richard I

    2013-01-01

    Overlapping absorption edges will occur when an element is present in multiple oxidation states within a material. DetOx is a program for partitioning overlapping X-ray absorption spectra into contributions from individual atomic species and computing the dependence of the anomalous scattering factors on X-ray energy. It is demonstrated how these results can be used in combination with X-ray diffraction data to determine the oxidation state of ions at specific sites in a mixed-valance material, GaCl(2).

  4. Surgical wound healing in radio-tagged adult Pacific lamprey Entosphenus tridentatus held on different substrata

    Science.gov (United States)

    Mesa, M.G.; Magie, R.J.; Copeland, E.S.; Christiansen, H.E.

    2011-01-01

    Radio-tagged adult Pacific lamprey Entosphenus tridentatus held in a raceway with Plexiglas-lined walls and bottom healed more slowly and retained sutures longer than fish held in an all-concrete raceway or one with Plexiglas walls and a cobble-lined bottom. On all substrata, healing depended on when sutures were lost, and fish that lost their sutures in healed faster than those that kept sutures longer. Long-term suture retention led to tissue trauma, infection and poor survival.

  5. Establishment of a method for determination of arsenic species in seafood by LC-ICP-MS.

    Science.gov (United States)

    Zmozinski, Ariane V; Llorente-Mirandes, Toni; López-Sánchez, José F; da Silva, Márcia M

    2015-04-15

    An analytical method for determination of arsenic species (inorganic arsenic (iAs), methylarsonic acid (MA), dimethylarsinic acid (DMA), arsenobetaine (AB), trimethylarsine oxide (TMAO) and arsenocholine (AC)) in Brazilian and Spanish seafood samples is reported. This study was focused on extraction and quantification of inorganic arsenic (iAs), the most toxic form. Arsenic speciation was carried out via LC with both anionic and cationic exchange with ICP-MS detection (LC-ICP-MS). The detection limits (LODs), quantification limits (LOQs), precision and accuracy for arsenic species were established. The proposed method was evaluated using eight reference materials (RMs). Arsenobetaine was the main species found in all samples. The total and iAs concentration in 22 seafood samples and RMs ranged between 0.27-35.2 and 0.02-0.71 mg As kg(-1), respectively. Recoveries ranging from 100% to 106% for iAs, based on spikes, were achieved. The proposed method provides reliable iAs data for future risk assessment analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Determination of antifungal susceptibility patterns among the clinical isolates of Candida species

    Directory of Open Access Journals (Sweden)

    Kamiar Zomorodian

    2011-01-01

    Full Text Available Context: Candida species are opportunistic yeasts that cause infections ranging from simple dermatosis to potentially life-threatening fungemia. The emergence of resistance to antifungal drugs has been increased in the past two decades. Aim: the present study we determined to find out the susceptibility profiles of clinical isolates of Candida species against four antifungal drugs, including amphotericin B, ketoconazole, fluconazole and itraconazole. Materials and Methods: Antifungal susceptibility testing of the yeasts was done in accordance with the proposed guidelines for antifungal disk diffusion susceptibility testing of yeasts based on the CLSI document M44-A. Results: A total of 206 yeast isolates were assessed. Among the evaluated Candida species, the highest rates of resistance to ketoconazole were seen in Candida glabrata (16.6% and Candida albicans (3.2%. Susceptibility and intermediate response to fluconazole were seen in 96.6% and 3.4% of the Candida isolates, respectively. A total of 19 (9.2% yeast isolates showed petite phenomenon including 11 C. glabrata, 3 C. albicans, 2 Candida dubliniensis and one isolate of each Candida krusei and Candida parapsilosis. Conclusion: The high number of petite mutation in the isolated yeasts should be seriously considered since it may be one of the reasons of antifungal treatment failure.

  7. Approach to determine the diversity of Legionella species by nested PCR-DGGE in aquatic environments

    Science.gov (United States)

    Huang, Wen-Chien; Tsai, Hsin-Chi; Tao, Chi-Wei; Chen, Jung-Sheng; Shih, Yi-Jia; Kao, Po-Min; Huang, Tung-Yi; Hsu, Bing-Mu

    2017-01-01

    In this study, we describe a nested PCR-DGGE strategy to detect Legionella communities from river water samples. The nearly full-length 16S rRNA gene was amplified using bacterial primer in the first step. After, the amplicons were employed as DNA templates in the second PCR using Legionella specific primer. The third round of gene amplification was conducted to gain PCR fragments apposite for DGGE analysis. Then the total numbers of amplified genes were observed in DGGE bands of products gained with primers specific for the diversity of Legionella species. The DGGE patterns are thus potential for a high-throughput preliminary determination of aquatic environmental Legionella species before sequencing. Comparative DNA sequence analysis of excised DGGE unique band patterns showed the identity of the Legionella community members, including a reference profile with two pathogenic species of Legionella strains. In addition, only members of Legionella pneumophila and uncultured Legionella sp. were detected. Development of three step nested PCR-DGGE tactic is seen as a useful method for studying the diversity of Legionella community. The method is rapid and provided sequence information for phylogenetic analysis. PMID:28166249

  8. Macro- and microelement determination of some species of the family Fumaria L. distributed in Bulgaria

    International Nuclear Information System (INIS)

    Marichkova, L.; K'ostarova, O.

    1985-01-01

    The mineral composition of different species of the family Fumaria L. is of interest as it is widely used in traditional popular medicine and participates in metabolism of the human body.The micro- and macroelement determination was carried out by means of nondestructive neutron activation analysis. The measured probes and standards were irradiated in Sofia IRT-reactor for the time periods according to radioactive isotope activations. The elements Mn, Sr, Zr were determined using radioisitope X-ray fluorescence analysis for both the plants and the soils. Cd 109 source, Si(Li) detectoprt and Nockie multichannel analyser were used. It was found that particularly useful for the quantities of drugs are the elements: Ca, Cu, K, Co and Fe

  9. 78 FR 41227 - Endangered and Threatened Wildlife and Plants; Determination of Endangered Species Status for Six...

    Science.gov (United States)

    2013-07-09

    ... of an endangered species under the Endangered Species Act of 1973: Phantom springsnail (Pyrgulopsis... final rule implements the Federal protections provided by the Endangered Species Act for these species... Wildlife under the Endangered Species Act. DATES: This rule becomes effective August 8, 2013. ADDRESSES...

  10. Determination of sixteen elements and arsenic species in brown, polished and milled rice.

    Science.gov (United States)

    Narukawa, Tomohiro; Matsumoto, Eri; Nishimura, Tsutomu; Hioki, Akiharu

    2014-01-01

    The concentrations of 16 elements in 10 rice flour samples and the distribution of the elements in the rice grains from which the flour were made were determined by ICP-MS and ICP-OES after microwave-assisted digestion of the samples. Arsenic speciation analysis was carried out by HPLC-ICP-MS following heat-assisted extraction of the sample. The concentrations of inorganic As (As(III) and As(V)), monomethylarsonic acid (MMAA) and dimethylarsinic acid (DMAA) and their distribution in the rice grains were determined. Portions of the brown rice were polished/milled to different degrees to yield milled off samples and polished rice samples. All samples were powdered and analyzed for 16 elements and for As species. The recoveries and mass balances for all elements in all samples showed good agreements with the starting materials. As(III), As(V), MMAA and DMAA were detected, and the sums of the concentrations of all species in the extract were 86-105% of the total As concentration in each case.

  11. Determination of the antioxidant capacity of two seagrass species according to the extraction method

    Directory of Open Access Journals (Sweden)

    Kethia L. González

    2016-10-01

    Full Text Available Context: There is a wide variety of methods for obtaining of plant extracts that enable a good yield of bioactive metabolites. For several years, extractive techniques have been perfected for obtaining natural extracts with powerful pharmacological properties. Aims: To determine the influence of various extraction methods (infusion, decoction, microwave, maceration with heat and agitation, and constant heat and agitation on the content of solids, phenolic compounds and antioxidant capacity of marine angiosperms Thalassia testudinum Banks ex König (Hyrocharitacea and Syringodium filiforme kützing (Cymodoceaceae. Methods: The soluble solids content was determined by the gravimetric method; total phenolic content, using Folin-Ciocalteu method, and the antioxidant capacity by 2,2-diphenyl-1 picrylhydrazyl (DPPH method. Results: Results showed the effectiveness of extraction by decoction for T. testudinum and by microwave for S. filiforme, among the methods that use water as the extraction solvent. In the case those that use the hydroalcoholic mixture as solvent extraction, maceration with agitation and heat extraction showed the higher yields of soluble solids and total polyphenols, as well as a higher antioxidant activity for both species. Conclusions: Results showed the effectiveness of extraction by decoction for T. testudinum and by microwave for S. filiforme, among the methods that use water as extraction solvent. In the case those that use hydroalcoholic mixture as solvent extraction, maceration with agitation and heat extraction showed the higher yields of soluble solids and total polyphenols, as well as a higher antioxidant activity for both species.

  12. Determination of Iron Species by Combination of Solvent Assisted-Dispersive Solid Phase Extraction and Spectrophotometry

    Directory of Open Access Journals (Sweden)

    Zahra Dehghani

    2015-06-01

    Full Text Available A simple, rapid and sensitive solvent assisted-dispersive solid phase extraction method was developed for the extraction of iron(II prior to its spectrophotometric determination. The Fe(II reacted with 2,4,6-tris(2-pyridyl-1,3,5-triazine, neutralized with sodium dodecyl sulfate and extracted onto the fine particles of benzophenone which were formed upon rapid injection of a mixture of benzophenone as the sorbent and ethanol as the disperser solvent into the aqueous solution. After phase separation, the sedimented phase containing the complex was dissolved in ethanol and the analyte concentration was determined by measuring its absorption at 594 nm. Total iron was determined after the reduction of Fe(III to Fe(II with hydroxylamine hydrochloride. Under the optimized conditions, an enhancement factor of 32, the detection limit of 0.16 µg l-1, and the relative standard deviation of 1.9% (n = 6 at 20 µg l-1 concentration level of Fe(II were achieved. The method was successfully applied to the determination of iron species in water samples and total iron in infant dry formula milk, apple, rice, spinach and parsley samples.

  13. Strategies for swimming: explorations of the behaviour of a neuro-musculo-mechanical model of the lamprey

    Directory of Open Access Journals (Sweden)

    Thelma L. Williams

    2015-02-01

    Full Text Available Experiments were performed on a neuro-musculo-mechanical model of a lamprey, to explore the strategies for controlling swimming speed. The muscle component of the model was based on previous experiments on isolated lamprey muscle. The patterns of muscle activation were those found in EMG studies on swimming lampreys. The fluid mechanics were modelled with G.I. Taylor's simplification. Tail beat frequencies of 2–6 sec−1 were combined with muscle activation strengths of 0.1% to 20% of maximum tetanic isometric strength. The resulting forward swimming speed and changing body shape were recorded. From the changing body shape the speed of the backward-travelling wave of curvature was calculated, as well as the ratio between the speeds of the waves of activation and curvature. For any given activation strength there was a tail beat frequency that gave maximal forward speed. Furthermore, for all the combinations of activation strength and tail beat frequency that gave such maximum swimming speeds, the ratio of the speed of the wave of curvature to the wave of muscle activation was approximately 0.75. This is similar to the ratio found in swimming lampreys.

  14. Re-examination of sea lamprey control policies for the St. Marys River: Completion of an adaptive management cycle

    Science.gov (United States)

    Jones, Michael L.; Brenden, Travis O.; Irwin, Brian J.

    2015-01-01

    The St. Marys River (SMR) historically has been a major producer of sea lampreys (Petromyzon marinus) in the Laurentian Great Lakes. In the early 2000s, a decision analysis (DA) project was conducted to evaluate sea lamprey control policies for the SMR; this project suggested that an integrated policy of trapping, sterile male releases, and Bayluscide treatment was the most cost-effective policy. Further, it concluded that formal assessment of larval sea lamprey abundance and distribution in the SMR would be valuable for future evaluation of control strategies. We updated this earlier analysis, adding information from annual larval assessments conducted since 1999 and evaluating additional control policies. Bayluscide treatments continued to be critical for sea lamprey control, but high recruitment compensation minimized the effectiveness of trapping and sterile male release under current feasible ranges. Because Bayluscide control is costly, development of strategies to enhance trapping success remains a priority. This study illustrates benefits of an adaptive management cycle, wherein models inform decisions, are updated based on learning achieved from those decisions, and ultimately inform future decisions.

  15. The lamprey: a jawless vertebrate model system for examining origin of the neural crest and other vertebrate traits.

    Science.gov (United States)

    Green, Stephen A; Bronner, Marianne E

    2014-01-01

    Lampreys are a group of jawless fishes that serve as an important point of comparison for studies of vertebrate evolution. Lampreys and hagfishes are agnathan fishes, the cyclostomes, which sit at a crucial phylogenetic position as the only living sister group of the jawed vertebrates. Comparisons between cyclostomes and jawed vertebrates can help identify shared derived (i.e. synapomorphic) traits that might have been inherited from ancestral early vertebrates, if unlikely to have arisen convergently by chance. One example of a uniquely vertebrate trait is the neural crest, an embryonic tissue that produces many cell types crucial to vertebrate features, such as the craniofacial skeleton, pigmentation of the skin, and much of the peripheral nervous system (Gans and Northcutt, 1983). Invertebrate chordates arguably lack unambiguous neural crest homologs, yet have cells with some similarities, making comparisons with lampreys and jawed vertebrates essential for inferring characteristics of development in early vertebrates, and how they may have evolved from nonvertebrate chordates. Here we review recent research on cyclostome neural crest development, including research on lamprey gene regulatory networks and differentiated neural crest fates. Copyright © 2014 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  16. Effects of coded-wire-tagging on stream-dwelling Sea Lamprey larvae

    Science.gov (United States)

    Johnson, Nicholas; Swink, William D.; Dawson, Heather A.; Jones, Michael L.

    2016-01-01

    The effects of coded wire tagging Sea Lamprey Petromyzon marinus larvae from a known-aged stream-dwelling population were assessed. Tagged larvae were significantly shorter on average than untagged larvae from 3 to 18 months after tagging. However, 30 months after tagging, the length distribution of tagged and untagged larvae did not differ and tagged Sea Lampreys were in better condition (i.e., higher condition factor) and more likely to have undergone metamorphosis than the untagged population. The reason why tagged larvae were more likely to metamorphose is not clear, but the increased likelihood of metamorphosis could have been a compensatory response to the period of slower growth after tagging. Slower growth after tagging was consistent across larval size-classes, so handling and displacement from quality habitat during the early part of the growing season was likely the cause rather than the tag burden. The tag effects observed in this study, if caused by displacement and handling, may be minimized in future studies if tagging is conducted during autumn after growth has concluded for the year.

  17. Amphioxus and lamprey AP-2 genes: implications for neural crest evolution and migration patterns

    Science.gov (United States)

    Meulemans, Daniel; Bronner-Fraser, Marianne

    2002-01-01

    The neural crest is a uniquely vertebrate cell type present in the most basal vertebrates, but not in cephalochordates. We have studied differences in regulation of the neural crest marker AP-2 across two evolutionary transitions: invertebrate to vertebrate, and agnathan to gnathostome. Isolation and comparison of amphioxus, lamprey and axolotl AP-2 reveals its extensive expansion in the vertebrate dorsal neural tube and pharyngeal arches, implying co-option of AP-2 genes by neural crest cells early in vertebrate evolution. Expression in non-neural ectoderm is a conserved feature in amphioxus and vertebrates, suggesting an ancient role for AP-2 genes in this tissue. There is also common expression in subsets of ventrolateral neurons in the anterior neural tube, consistent with a primitive role in brain development. Comparison of AP-2 expression in axolotl and lamprey suggests an elaboration of cranial neural crest patterning in gnathostomes. However, migration of AP-2-expressing neural crest cells medial to the pharyngeal arch mesoderm appears to be a primitive feature retained in all vertebrates. Because AP-2 has essential roles in cranial neural crest differentiation and proliferation, the co-option of AP-2 by neural crest cells in the vertebrate lineage was a potentially crucial event in vertebrate evolution.

  18. Multiple functions of a multi-component mating pheromone in sea lamprey Petromyzon marinus

    Science.gov (United States)

    Johnson, N.S.; Yun, S.-S.; Buchinger, T.J.; Li, W.

    2012-01-01

    The role of the C24 sulphate in the mating pheromone component, 7α,12α,24-trihydroxy-5α-cholan-3-one 24-sulphate (3kPZS), to specifically induce upstream movement in ovulated female sea lampreys Petromyzon marinus was investigated. 7α,12α-dihydroxy-5α-cholan-3-one 24-oic acid (3kACA), a structurally similar bile acid released by spermiated males, but lacking the C24 sulphate ester, was tested in bioassays at concentrations between 10−11 and 10−14 molar (M). 3kACA did not induce upstream movement in females or additional reproductive behaviours. In contrast, spermiated male washings induced upstream movement, prolonged retention on a nest and induced an array of nesting behaviours. Differential extraction and elution by solid-phase extraction resins showed that components other than 3kPZS + 3kACA are necessary to retain females on nests and induce nest cleaning behaviours. All pheromone components, including components in addition to 3kPZS + 3kACA that retain females and induce nest cleaning behaviours were released from the anterior region of the males, as had been reported for 3kPZS. It is concluded that the sea lamprey male mating pheromone has multiple functions and is composed of multiple components.

  19. Diatom species composition and indices for determining the ecological status of coastal Mediterranean Spanish lakes

    Directory of Open Access Journals (Sweden)

    Antón-Garrido, Beatriz

    2013-12-01

    Full Text Available Diatom indices have been used and tested mainly for assessing the ecological status of rivers and deep lakes, but there are scarce studies that determine their effectiveness in shallow lakes and in coastal Mediterranean lakes. This study evaluates the validity of several common diatom indices (SPI, BDI, CEC and TDIL for the determination of the ecological quality of three coastal lakes (Valencia, Spain and presents descriptions and ecological data of the main diatom species recorded. Diatom samples were collected from phytobenthos, both from epiphyton of the dominant submerged macrophytes and the sediment. The ecological status of the systems was determined according to different physico-chemical variables and was compared with the results obtained from epiphytic diatom communities. The results showed discrepancies among diatom indices and also with the state determined by the environmental variables. The effectiveness of the indices depended on the number of species assessed for each index with respect to the total species recorded and the suitability of the weight assigned to each species. The results reveal the need to gather more information about the composition and ecology of the diatoms and microalgae characteristic of coastal Mediterranean standing waters. This work contributes to their better knowledge.Los índices de diatomeas han sido aplicados y contrastados principalmente en la evaluación del estado ecológico de los sistemas lóticos y lagos profundos, pero son escasos los estudios sobre su eficacia en lagos someros y lagunas litorales mediterráneas. Este trabajo evalúa la validez de varios índices conocidos de diatomeas (IPS, IBD, CEE y TDIL para la determinación de la calidad ecológica de tres lagunas litorales (Valencia, España y presenta las descripciones y datos ecológicos de las principales especies de diatomeas registradas. Las muestras de diatomeas se recogieron del fitobentos, tanto del epifiton desarrollado sobre

  20. Determination of macro and micronutrients and nutritional prospects of six vegetable species of Mardan, Pakistan

    International Nuclear Information System (INIS)

    Sami, F.; Shinwari, Z.K.

    2011-01-01

    This study was carried out to assess the nutritional an d mineral composition of selected vegetables, which are commonly used as food in Pakistan. Abel moschus esculentus, Solanum melongena , Cucurbita moschata, Allium sativum, Momordica charantia and Portulaca oleracea were collected form Mardan (Pakistan) and subjected to nutrient analysis. Nutrient analysis (total proteins, fats, carbohydrates, ash, energy value and moisture contents) of vegetable species were determined according to AOAC methods. Macro viz. calcium (Ca), magnesium (Mg), potassium (K), sodium (Na), and phosphorus (P) and micro viz. iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), nickel (Ni) and selenium (Se) elements were analyzed using Atomic Absorption Spectrometric method. The moisture (wet and dry basis), ash, fats, fibers, proteins, energy value (305.9 - 382.6 Kcal/100 g) and carbohydrates of these vegetable species were found in the range of 62.9 - 92.7, 5.4-7.7, 3.1 - 23.1, 0.3-8.3, 10.2-22.5, 7.7 - 16.9, and 51.3 - 80.2% respectively. The micronutrients including Fe, Zn, Mn, and Cu were found to be in the range, 6.2-24.1, 0.2-11.7, 0.6-16.7, and 0.1-70 ppm respectively. The results of macronutrients obtained having values of Ca (90-1850 ppm), Mg (94-571 ppm), K (2078-4010 ppm), Na (2-170 ppm), and P (250-1532 ppm) respectively. The quantity of Ni and Se were found negligible in these vegetables. The results indicate that all these vegetables have the potential to provide essential nutrients to the human beings. Momordica charantia and Allium sativum were found to be a good source of proteins, fats, carbohydrates, hence capable of providing energy to the consumer. Both these species were found significantly useful in terms of minerals sources, particularly Ni, K, P, Zn, Cu, and Mn. (author)

  1. Can standard sequential extraction determinations effectively define heavy metal species in superfund site soils?

    Energy Technology Data Exchange (ETDEWEB)

    Dahlin, Cheryl L.; Williamson, Connie A.; Collins, Wesley K.; Dahlin, David C.

    2001-01-01

    Speciation and distribution of heavy metals in soils controls the degree to which metals and their compounds are mobile, extractable, and plant-available. Consequently, speciation impacts the success of remediation efforts both by defining the relationship of the contaminants with their environment and by guiding development and evaluation of workable remediation strategies. The U.S. Department of Energy, Albany Research Center (Albany, OR), under a two-year interagency project with the U.S. Environmental Protection Agency (EPA), examined the suitability of sequential extraction as a definitive means to determine species of heavy metals in soil samples. Representative soil samples, contaminated with lead, arsenic, and/or chromium, were collected by EPA personnel from two Superfund sites, the National Lead Company site in Pedricktown, NJ, and the Roebling Steel, Inc., site in Florence, NJ. Data derived from Tessier=s standard three-stage sequential-extraction procedure were compared to data from a comprehensive characterization study that combined optical- and scanning-electron microscopy (with energy-dispersive x-ray and wavelength-dispersive x-ray analyses), x-ray diffraction, and chemical analyses. The results show that standard sequential-extraction procedures that were developed for characterizing species of contaminants in river sediments may be unsuitable for sole evaluation of contaminant species in industrial-site materials (particularly those that contain larger particles of the contaminants, encapsulated contaminants, and/or man-made materials such as slags, metals, and plastics). However, each sequential extraction or comprehensive characterization procedure has it=s own strengths and weaknesses. Findings of this study indicate that the use of both approaches, during the early stages of site studies, would be a best practice. The investigation also highlights the fact that an effective speciation study does not simply identify metal contaminants as

  2. On the Mechanism(s of Membrane Permeability Transition in Liver Mitochondria of Lamprey, Lampetra fluviatilis L.: Insights from Cadmium

    Directory of Open Access Journals (Sweden)

    Elena A. Belyaeva

    2014-01-01

    Full Text Available Previously we have shown that opening of the mitochondrial permeability transition pore in its low conductance state is the case in hepatocytes of the Baltic lamprey (Lampetra fluviatilis L. during reversible metabolic depression taking place in the period of its prespawning migration when the exogenous feeding is switched off. The depression is observed in the last year of the lamprey life cycle and is conditioned by reversible mitochondrial dysfunction (mitochondrial uncoupling in winter and coupling in spring. To further elucidate the mechanism(s of induction of the mitochondrial permeability transition pore in the lamprey liver, we used Cd2+ and Ca2+ plus Pi as the pore inducers. We found that Ca2+ plus Pi induced the high-amplitude swelling of the isolated “winter” mitochondria both in isotonic sucrose and ammonium nitrate medium while both low and high Cd2+ did not produce the mitochondrial swelling in these media. Low Cd2+ enhanced the inhibition of basal respiration rate of the “winter” mitochondria energized by NAD-dependent substrates whereas the same concentrations of the heavy metal evoked its partial stimulation on FAD-dependent substrates. The above changes produced by Cd2+ or Ca2+ plus Pi in the “winter” mitochondria were only weakly (if so sensitive to cyclosporine A (a potent pharmacological desensitizer of the nonselective pore added alone and they were not sensitive to dithiothreitol (a dithiol reducing agent. Under monitoring of the transmembrane potential of the “spring” lamprey liver mitochondria, we revealed that Cd2+ produced its decrease on both types of the respiratory substrates used that was strongly hampered by cyclosporine A, and the membrane potential was partially restored by dithiothreitol. The effects of different membrane permeability modulators on the lamprey liver mitochondria function and the seasonal changes in their action are discussed.

  3. Determining the Ratio of Animal Species in the Herd of Pre-Class Societies

    Directory of Open Access Journals (Sweden)

    Stegantsev Mark A.

    2013-09-01

    Full Text Available The article is devoted to the methodology of research of domestic animals herd composition in ancient societies, based on the materials of Late Bronze and Early Iron Age sites located in the Western part of forest-steppe and steppe of Western Siberia and Northern Kazakhstan. The theoretical portion of the article demonstrates that percentage composition of the ancient herd can be restored only by taking into account the early maturation of the domestic ungulates forming its component part. The values of their early maturation depend on the distribution of animals by age. The formulas, derived through herd models developed, make it possible to determine the required distribution, based on the number of animal units of different ages in osteological collections. They are not affected by the type of herd reproduction. The application of the derived formulas in order to determine the early maturation of large and small cattle, and horses in the settlements of certain cultures in forest, forest-steppe and steppe zones, has confirmed the adequacy of the model in explaining the archaeological data. It has also been shown that economic specialization of successive Late Bronze and Early Iron Age cultures in the region was determined mainly by the horse. The study of different methods of determining ancient herd composition has made it possible to come to the following conclusion. The method of transition from identifiable bones in the excavation to the number of animal units corresponding to them, and then, by determining early maturation of different species, to their ratio in the ancient herd, has an absolute priority as compared to the method of transition from the identifiable bones directly to herd composition.

  4. How Many Parasites Species a Frog Might Have? Determinants of Parasite Diversity in South American Anurans.

    Directory of Open Access Journals (Sweden)

    Karla Magalhães Campião

    Full Text Available There is an increasing interest in unveiling the dynamics of parasite infection. Understanding the interaction patterns, and determinants of host-parasite association contributes to filling knowledge gaps in both community and disease ecology. Despite being targeted as a relevant group for conservation efforts, determinants of the association of amphibians and their parasites in broad scales are poorly understood. Here we describe parasite biodiversity in South American amphibians, testing the influence of host body size and geographic range in helminth parasites species richness (PSR. We also test whether parasite diversity is related to hosts' phylogenetic diversity. Results showed that nematodes are the most common anuran parasites. Host-parasite network has a nested pattern, with specialist helminth taxa generally associated with hosts that harbour the richest parasite faunas. Host size is positively correlated with helminth fauna richness, but we found no support for the association of host geographic range and PSR. These results remained consistent after correcting for uneven study effort and hosts' phylogenic correlation. However, we found no association between host and parasite diversity, indicating that more diversified anuran clades not necessarily support higher parasite diversity. Overall, considering both the structure and the determinants of PRS in anurans, we conclude that specialist parasites are more likely to be associated with large anurans, which are the ones harbouring higher PSR, and that the lack of association of PSR with hosts' clade diversification suggests it is strongly influenced by ecological and contemporary constrains.

  5. Determination of inorganic beryllium species in the particulate matter of emissions and working areas

    Energy Technology Data Exchange (ETDEWEB)

    Profumo, A.; Spini, G.; Cucca, L.; Pesavento, M. [Dipartimento di Chimica Gen., Pavia (Italy)

    2002-07-01

    A sequential extraction procedure for separating and determining Be(0), soluble Be(II) inorganic compounds, BeO and beryllium silicates in samples, such as particulate matter of emissions and working areas, has been developed. The proposed procedure has been tested on synthetic samples prepared with the inorganic beryllium compounds, in the presence of atmospherical particulate matter sampled in a laboratory, previously checked for the absence of beryllium. The speciation was then repeated on a sample of fly ash deriving from a solid waste incinerator and on a reference material (Coal Fly ash SRM 1633a, by NIST), followed by an evaluation of matrix spiking and recovery analyses. Performing multiple analyses of the spiked samples assessed the repeatability of the procedure. Quantitative determinations have been made by inductively coupled plasma optical emission spectrometry (ICP-OES) and electrothermal atomic absorption spectrometry (ETAAS). The possible interferences of the most common ions have been investigated. The selective sequential extractions allow one to separate and to determine different inorganic beryllium species, to which a different toxicity and therefore, a different risk are related: it is the case for example of metallic beryllium and beryllium oxide.

  6. Development of extraction procedure for determination of mercury species using SPME-assisted dispersive derivative agent

    Science.gov (United States)

    Abdullah, Md Pauzi; Khalik, Wan Mohd Afiq Wan Mohd; Othman, Mohamed Rozali

    2016-11-01

    The extraction procedure for determination of low level mercury using solid phase microextraction was successfully carried out. Design of experimental works using factorial design and central composite design were applied to screen and predict the optimum condition for extraction step. In this study, variables namely concentration level (5 % m/v) and volume of derivatization solution (150 µL) has depicted as main effect for controlling the suitability of derivative reagent condition. Maximum of signal response (account as total peak areas for mercury species) was obtained when extraction procedure was set up at pH of water sample (5.8), extraction time (14 min), extraction temperature (43 °C) and stirring rate (450 rpm). Reducing time required to reach equilibrium is new improvement achieved in this study. Detection limit for each species (MeHg 26.17 ngL-1; EtHg 48.84 ngL-1 and IHg 14.11 ngL-1) was calculated lower than our previous work. Recovery, repeatability and reproducibility trial were recorded varied at acceptable range and relative standard deviation was calculated below than 10 %.

  7. Plastome Sequence Determination and Comparative Analysis for Members of the Lolium-Festuca Grass Species Complex

    Science.gov (United States)

    Hand, Melanie L.; Spangenberg, German C.; Forster, John W.; Cogan, Noel O. I.

    2013-01-01

    Chloroplast genome sequences are of broad significance in plant biology, due to frequent use in molecular phylogenetics, comparative genomics, population genetics, and genetic modification studies. The present study used a second-generation sequencing approach to determine and assemble the plastid genomes (plastomes) of four representatives from the agriculturally important Lolium-Festuca species complex of pasture grasses (Lolium multiflorum, Festuca pratensis, Festuca altissima, and Festuca ovina). Total cellular DNA was extracted from either roots or leaves, was sequenced, and the output was filtered for plastome-related reads. A comparison between sources revealed fewer plastome-related reads from root-derived template but an increase in incidental bacterium-derived sequences. Plastome assembly and annotation indicated high levels of sequence identity and a conserved organization and gene content between species. However, frequent deletions within the F. ovina plastome appeared to contribute to a smaller plastid genome size. Comparative analysis with complete plastome sequences from other members of the Poaceae confirmed conservation of most grass-specific features. Detailed analysis of the rbcL–psaI intergenic region, however, revealed a “hot-spot” of variation characterized by independent deletion events. The evolutionary implications of this observation are discussed. The complete plastome sequences are anticipated to provide the basis for potential organelle-specific genetic modification of pasture grasses. PMID:23550121

  8. Endothelial cell tropism is a determinant of H5N1 pathogenesis in mammalian species.

    Directory of Open Access Journals (Sweden)

    Smanla Tundup

    2017-03-01

    Full Text Available The cellular and molecular mechanisms underpinning the unusually high virulence of highly pathogenic avian influenza H5N1 viruses in mammalian species remains unknown. Here, we investigated if the cell tropism of H5N1 virus is a determinant of enhanced virulence in mammalian species. We engineered H5N1 viruses with restricted cell tropism through the exploitation of cell type-specific microRNA expression by incorporating microRNA target sites into the viral genome. Restriction of H5N1 replication in endothelial cells via miR-126 ameliorated disease symptoms, prevented systemic viral spread and limited mortality, despite showing similar levels of peak viral replication in the lungs as compared to control virus-infected mice. Similarly, restriction of H5N1 replication in endothelial cells resulted in ameliorated disease symptoms and decreased viral spread in ferrets. Our studies demonstrate that H5N1 infection of endothelial cells results in excessive production of cytokines and reduces endothelial barrier integrity in the lungs, which culminates in vascular leakage and viral pneumonia. Importantly, our studies suggest a need for a combinational therapy that targets viral components, suppresses host immune responses, and improves endothelial barrier integrity for the treatment of highly pathogenic H5N1 virus infections.

  9. DETERMINATION OF THE TOXIC EFFECTS OF MERCURY IN THE Brachiaria dictyoneura (Fig. & De Not. Stapf SPECIES

    Directory of Open Access Journals (Sweden)

    Gladis E. Morales

    2013-03-01

    Full Text Available In this research has been evaluated, on a laboratory scale, the toxic effect of mercury on the root development and biomass growth of the Brachiaria dictyoneura species, with the goal of finding an adequate concentration interval for the study on the accumulation of Hg (II. Brachiaria dictyoneura seeds were exposed to different amounts of mercury, the germination kinetics were determined, and after a 20 day growth period the length of the roots and the biomass were measured. There were found harmful effects on the root development starting at 25 mg*kg-1 Hg (II; for the dry biomass the differences were found starting at 5 mg*kg-1 Hg (II and starting at 75 mg*kg-1 Hg (II for the seed emergency time, therefore, working with concentrations not exceeding 25 mg Hg(II*kg-1 of substrate is suggested.

  10. Mayfly and fish species identification and sex determination in bleak (Alburnus alburnus) by MALDI-TOF mass spectrometry.

    Science.gov (United States)

    Maasz, G; Takács, P; Boda, P; Varbiro, G; Pirger, Z

    2017-12-01

    Besides food quality control of fish or cephalopods, the novel mass spectrometry (MS) approaches could be effective and beneficial methods for the investigation of biodiversity in ecological research. Our aims were to verify the applicability of MALDI-TOF MS in the rapid identification of closely related species, and to further develop it for sex determination in phenotypically similar fish focusing on the low mass range. For MALDI-TOF MS spectra analysis, ClinProTools software was applied, but our observed classification was also confirmed by Self Organizing Map. For verifying the wide applicability of the method, brains from invertebrate and vertebrate species were used in order to detect the species related markers from two mayflies and eight fish as well as sex-related markers within bleak. Seven Ephemera larvae and sixty-one fish species related markers were observed and nineteen sex-related markers were identified in bleak. Similar patterns were observed between the individuals within one species. In contrast, there were markedly diverse patterns between the different species and sexes visualized by SOMs. Two different Ephemera species and male or female fish were identified with 100% accuracy. The various fish species were classified into 8 species with a high level of accuracy (96.2%). Based on MS data, dendrogram was generated from different fish species by using ClinProTools software. This MS-based dendrogram shows relatively high correspondence with the phylogenetic relationships of both the studied species and orders. In summary, MALDI-TOF MS provides a cheap, reliable, sensitive and fast identification tool for researchers in the case of closely related species using mass spectra acquired in a low mass range to define specific molecular profiles. Moreover, we presented evidence for the first time for determination of sex within one fish species by using this method. We conclude that it is a powerful tool that can revolutionize ecological and

  11. Assessment of Fluctuating Reservoir Elevations Using Hydraulic Models and Impacts to Larval Pacific Lamprey Rearing Habitat in the Bonneville Pool

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Robert P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rakowski, Cynthia L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Perkins, William A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Richmond, Marshall C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-02-24

    This report presents the results of a modeling assessment of likely lamprey larval habitat that may be impacted by dewatering of the major tributary delta regions in the Bonneville Pool of the Columbia River. This assessment was conducted by the Pacific Northwest National Laboratory (PNNL) for the U.S. Army Corps of Engineers Portland District (CENWP). The goal of the study was to provide baseline data about how the regions of interest would potentially be impacted at three river flows (10, 50, and 90 percent exceedance flow) for four different forebay elevations at Bonneville Dam. Impacts of unsteady flows at The Dalles Dam and changing forebay elevation at Bonneville Dam for a 2-week period were also assessed. The area of dewatered regions was calculated by importing modeled data outputs into a GIS and then calculating the change in inundated area near tributary deltas for the four Bonneville forebay surface elevations. From the modeled output we determined that the overall change in area is less sensitive to elevations changes during higher river discharges. Changing the forebay elevation at Bonneville and the resulting impact to total dewatered regions was greater at the lowest modeled river flow (97 kcfs) and showed the greatest variation at the White Salmon/Hood River delta regions followed by the Wind, Klickitat and the Little White Salmon rivers. To understand how inundation might change on a daily and hourly basis. Unsteady flow models were run for a 2-week period in 2002 and compared to 2014. The water surface elevation in the upstream pool closely follows that of the Bonneville Dam forebay with rapid changes of 1 to 2-ft possible. The data shows that 2.5-ft variation in water surface elevation occurred during this period in 2002 and a 3.7-ft change occurred in 2014. The duration of these changes were highly variable and generally did not stay constant for more than a 5-hr period.

  12. Potentiometric determination of the 'formal' hydrolysis ratio of aluminium species in aqueous solutions

    International Nuclear Information System (INIS)

    Fournier, Agathe C.; Shafran, Kirill L.; Perry, Carole C.

    2008-01-01

    The 'formal' hydrolysis ratio (h = C(OH - ) added /C(Al) total ) of hydrolysed aluminium-ions is an important parameter required for the exhaustive and quantitative speciation-fractionation of aluminium in aqueous solutions. This paper describes a potentiometric method for determination of the formal hydrolysis ratio based on an automated alkaline titration procedure. The method uses the point of precipitation of aluminium hydroxide as a reference (h = 3.0) in order to calculate the initial formal hydrolysis ratio of hydrolysed aluminium-ion solutions. Several solutions of pure hydrolytic species including aluminium monomers (AlCl 3 ), Al 13 polynuclear cluster ([Al 13 O 4 (OH) 24 (H 2 O) 12 ] 7+ ), Al 30 polynuclear cluster ([Al 30 O 8 (OH) 56 (H 2 O) 26 ] 18+ ) and a suspension of nanoparticulate aluminium hydroxide have been used as 'reference standards' to validate the proposed potentiometric method. Other important variables in the potentiometric determination of the hydrolysis ratio have also been optimised including the concentration of aluminium and the type and strength of alkali (Trizma-base, NH 3 , NaHCO 3 , Na 2 CO 3 and KOH). The results of the potentiometric analysis have been cross-verified by quantitative 27 Al solution nuclear magnetic resonance ( 27 Al NMR) measurements. The 'formal' hydrolysis ratio of a commercial basic aluminium chloride has been measured as an example of a practical application of the developed technique

  13. Electrochemical Determination of the Antioxidant Potential of Some Less Common Fruit Species

    Directory of Open Access Journals (Sweden)

    Boris Krska

    2008-11-01

    Full Text Available Various berries and fruit types of less common fruit species are known to contain antioxidants. Consumption of high amounts of antioxidant flavonoids, which display a variety of biological properties, including antiproliferative and anti-inflammatory activity, may have a positive impact on human health, particularly for the prevention of cancer and other inflammatory diseases. In these studies, based on the hypothesis that the fruit extract with the highest content would possess significantly higher health benefits, flavonoid-rich extracts were obtained from some less common fruit species – Blue Honeysuckles (Lonicera Kamtschatica and Lonicera edulis, Turcz. ex. Freyn, Saskatoon berry (Amelanchier alnifolia Nutt. and Chinese Hawthorn (Crataegus pinnatifida BUNGE – grown from germplasm held at the Mendel University of Agriculture and Forestry in Brno, Czech Republic and then characterized in terms of biological value based on the results from a relative antioxidant capacity assessment. The antioxidant content evaluation was based on the total flavonoid amount, determined by liquid chromatography with electrochemical detection (HPLC-ED. A DPPH• test was applied as a reference. The antioxidant content measured in Chinese Hawthorn fruit extract identified it as a potent source of flavonoid antioxidants, with a content 9-fold higher than that seen in Amelanchier fruit. The multifunctional HPLC-ED array method coupled with a DPPH• reference appears to be the optimal analytical progress, accurately reflecting the nutritivetherapeutic properties of a fruit.

  14. Determinants of species richness patterns in the Netherlands across multiple taxonomic groups

    NARCIS (Netherlands)

    Schouten, M.A.; Verweij, P.A.; Barendrecht, A.; Kleukers, R.

    2009-01-01

    We examined the species richness patterns of five different species groups (mosses, reptiles and amphibians, grasshoppers and crickets, dragonflies, and hoverflies) in the Netherlands (41,500 km2) using sampling units of 5 × 5 km. We compared the spatial patterns of species richness of the five

  15. Balance of Interactions Determines Optimal Survival in Multi-Species Communities.

    Directory of Open Access Journals (Sweden)

    Anshul Choudhary

    Full Text Available We consider a multi-species community modelled as a complex network of populations, where the links are given by a random asymmetric connectivity matrix J, with fraction 1 - C of zero entries, where C reflects the over-all connectivity of the system. The non-zero elements of J are drawn from a Gaussian distribution with mean μ and standard deviation σ. The signs of the elements Jij reflect the nature of density-dependent interactions, such as predatory-prey, mutualism or competition, and their magnitudes reflect the strength of the interaction. In this study we try to uncover the broad features of the inter-species interactions that determine the global robustness of this network, as indicated by the average number of active nodes (i.e. non-extinct species in the network, and the total population, reflecting the biomass yield. We find that the network transitions from a completely extinct system to one where all nodes are active, as the mean interaction strength goes from negative to positive, with the transition getting sharper for increasing C and decreasing σ. We also find that the total population, displays distinct non-monotonic scaling behaviour with respect to the product μC, implying that survival is dependent not merely on the number of links, but rather on the combination of the sparseness of the connectivity matrix and the net interaction strength. Interestingly, in an intermediate window of positive μC, the total population is maximal, indicating that too little or too much positive interactions is detrimental to survival. Rather, the total population levels are optimal when the network has intermediate net positive connection strengths. At the local level we observe marked qualitative changes in dynamical patterns, ranging from anti-phase clusters of period 2 cycles and chaotic bands, to fixed points, under the variation of mean μ of the interaction strengths. We also study the correlation between synchronization and survival

  16. Generic Amplicon Deep Sequencing to Determine Ilarvirus Species Diversity in Australian Prunus.

    Science.gov (United States)

    Kinoti, Wycliff M; Constable, Fiona E; Nancarrow, Narelle; Plummer, Kim M; Rodoni, Brendan

    2017-01-01

    The distribution of Ilarvirus species populations amongst 61 Australian Prunus trees was determined by next generation sequencing (NGS) of amplicons generated using a genus-based generic RT-PCR targeting a conserved region of the Ilarvirus RNA2 component that encodes the RNA dependent RNA polymerase (RdRp) gene. Presence of Ilarvirus sequences in each positive sample was further validated by Sanger sequencing of cloned amplicons of regions of each of RNA1, RNA2 and/or RNA3 that were generated by species specific PCRs and by metagenomic NGS. Prunus necrotic ringspot virus (PNRSV) was the most frequently detected Ilarvirus , occurring in 48 of the 61 Ilarvirus -positive trees and Prune dwarf virus (PDV) and Apple mosaic virus (ApMV) were detected in three trees and one tree, respectively. American plum line pattern virus (APLPV) was detected in three trees and represents the first report of APLPV detection in Australia. Two novel and distinct groups of Ilarvirus -like RNA2 amplicon sequences were also identified in several trees by the generic amplicon NGS approach. The high read depth from the amplicon NGS of the generic PCR products allowed the detection of distinct RNA2 RdRp sequence variant populations of PNRSV, PDV, ApMV, APLPV and the two novel Ilarvirus -like sequences. Mixed infections of ilarviruses were also detected in seven Prunus trees. Sanger sequencing of specific RNA1, RNA2, and/or RNA3 genome segments of each virus and total nucleic acid metagenomics NGS confirmed the presence of PNRSV, PDV, ApMV and APLPV detected by RNA2 generic amplicon NGS. However, the two novel groups of Ilarvirus -like RNA2 amplicon sequences detected by the generic amplicon NGS could not be associated to the presence of sequence from RNA1 or RNA3 genome segments or full Ilarvirus genomes, and their origin is unclear. This work highlights the sensitivity of genus-specific amplicon NGS in detection of virus sequences and their distinct populations in multiple samples, and the

  17. Generic Amplicon Deep Sequencing to Determine Ilarvirus Species Diversity in Australian Prunus

    Directory of Open Access Journals (Sweden)

    Wycliff M. Kinoti

    2017-06-01

    Full Text Available The distribution of Ilarvirus species populations amongst 61 Australian Prunus trees was determined by next generation sequencing (NGS of amplicons generated using a genus-based generic RT-PCR targeting a conserved region of the Ilarvirus RNA2 component that encodes the RNA dependent RNA polymerase (RdRp gene. Presence of Ilarvirus sequences in each positive sample was further validated by Sanger sequencing of cloned amplicons of regions of each of RNA1, RNA2 and/or RNA3 that were generated by species specific PCRs and by metagenomic NGS. Prunus necrotic ringspot virus (PNRSV was the most frequently detected Ilarvirus, occurring in 48 of the 61 Ilarvirus-positive trees and Prune dwarf virus (PDV and Apple mosaic virus (ApMV were detected in three trees and one tree, respectively. American plum line pattern virus (APLPV was detected in three trees and represents the first report of APLPV detection in Australia. Two novel and distinct groups of Ilarvirus-like RNA2 amplicon sequences were also identified in several trees by the generic amplicon NGS approach. The high read depth from the amplicon NGS of the generic PCR products allowed the detection of distinct RNA2 RdRp sequence variant populations of PNRSV, PDV, ApMV, APLPV and the two novel Ilarvirus-like sequences. Mixed infections of ilarviruses were also detected in seven Prunus trees. Sanger sequencing of specific RNA1, RNA2, and/or RNA3 genome segments of each virus and total nucleic acid metagenomics NGS confirmed the presence of PNRSV, PDV, ApMV and APLPV detected by RNA2 generic amplicon NGS. However, the two novel groups of Ilarvirus-like RNA2 amplicon sequences detected by the generic amplicon NGS could not be associated to the presence of sequence from RNA1 or RNA3 genome segments or full Ilarvirus genomes, and their origin is unclear. This work highlights the sensitivity of genus-specific amplicon NGS in detection of virus sequences and their distinct populations in multiple samples

  18. The relative roles of local climate adaptation and phylogeny in determining leaf-out timing of temperate tree species

    Directory of Open Access Journals (Sweden)

    Elsa Desnoues

    2017-12-01

    Full Text Available Background Leaf out times of temperate forest trees are a prominent determinant of global carbon dynamics throughout the year. Abiotic cues of leaf emergence are well studied but investigation of the relative roles of shared evolutionary history (phylogeny and local adaptation to climate in determining the species-level responses to these cues is needed to better apprehend the effect of global change on leaf emergence. We explored the relative importance of phylogeny and climate in determining the innate leaf out phenology across the temperate biome. Methods We used an extensive dataset of leaf-out dates of 1126 temperate woody species grown in eight Northern Hemisphere common gardens. For these species, information on the native climate and phylogenetic position was collected. Using linear regression analyses, we examine the relative effect of climate variables and phylogeny on leaf out variation among species. Results Climate variables explained twice as much variation in leaf out timing as phylogenetic information, a process that was driven primarily by the complex interactive effects of multiple climate variables. Although the primary climate factors explaining species-level variation in leaf-out timing varied drastically across different families, our analyses reveal that local adaptation plays a stronger role than common evolutionary history in determining tree phenology across the temperate biome. Conclusions In the long-term, the direct effects of physiological adaptation to abiotic effects of climate change on forest phenology are likely to outweigh the indirect effects mediated through changes in tree species composition.

  19. Determination of Screw and Nail Withdrawal Resistance of Some Important Wood Species

    Directory of Open Access Journals (Sweden)

    Alper Aytekin

    2008-04-01

    Full Text Available In this study, screw and nail withdrawal resistance of fir (Abies nordmanniana, oak (Quercus robur L. black pine (Pinus nigra Arnold and Stone pine (Pinus pinea L. wood were determined and compared. The data represent the testing of withdrawal resistance of three types of screws as smart, serrated and conventional and common nails. The specimens were prepared according to TS 6094 standards. The dimensions of the specimens were 5x5x15cm and for all of the directions. Moreover, the specimens were conditioned at ambient room temperature and 65±2% relative humidity. The screws and nails were installed according to ASTM-D 1761 standards. Nail dimensions were 2.5mm diameter and 50 mm length, conventional screws were 4x50mm, serrated screws were 4x45mm and smart screws were 4x50mm. Results show that the maximum screw withdrawal resistance value was found in Stone pine for the serrated screw. There were no significant differences between Stone pine and oak regarding screw withdrawal resistance values. Conventional screw yielded the maximum screw withdrawal resistance value in oak, followed by Stone pine, black pine and fir. Oak wood showed the maximum screw withdrawal resistance value for the smart screw, followed by Stone pine, black pine, and fir. Oak wood showed higher nail withdrawal resistances than softwood species. It was also determined that oak shows the maximum nail withdrawal resistance in all types. The nail withdrawal resistances at the longitudinal direction are lower with respect to radial and tangential directions.

  20. What determines positive, neutral, and negative impacts of Solidago canadensis invasion on native plant species richness?

    Science.gov (United States)

    Dong, Li-Jia; Yu, Hong-Wei; He, Wei-Ming

    2015-11-17

    Whether plant invasions pose a great threat to native plant diversity is still hotly debated due to conflicting findings. More importantly, we know little about the mechanisms of invasion impacts on native plant richness. We examined how Solidago canadensis invasion influenced native plants using data from 291 pairs of invaded and uninvaded plots covering an entire invaded range, and quantified the relative contributions of climate, recipient communities, and S. canadensis to invasion impacts. There were three types of invasion consequences for native plant species richness (i.e., positive, neutral, and negative impacts). Overall, the relative contributions of recipient communities, S. canadensis and climate to invasion impacts were 71.39%, 21.46% and 7.15%, respectively; furthermore, the roles of recipient communities, S. canadensis and climate were largely ascribed to plant diversity, density and cover, and precipitation. In terms of direct effects, invasion impacts were negatively linked to temperature and native plant communities, and positively to precipitation and soil microbes. Soil microbes were crucial in the network of indirect effects on invasion impacts. These findings suggest that the characteristics of recipient communities are the most important determinants of invasion impacts and that invasion impacts may be a continuum across an entire invaded range.

  1. Identification and Determination of Drug Resistant of Candida species isolated from Hospital Acquired Infections

    Directory of Open Access Journals (Sweden)

    Kambiz Diba

    2015-01-01

    Full Text Available Background & aim: Currently, the use of antifungal azole group and yeasts resistant to these drugs is increasing. The aim of this study was to isolate and identify the yeasts obtained from candidiasis patients and furthermore determining thier antifungal resistance. Methods: In the present descriptive study, infections samples were collected from 256 patients with suspected nosocomial candidiasis, then direct exam and culture were performed. Yeast colonies were identified using phenotypic methods, polymerase chain reaction method and enzyme digestion. Data were analyzed using Descriptive statistical tests. Results: Of sixty isolated yeast, thirty-seven cases of Candida albicans (61.6%, seven cases of C. krusei and C. glabrata (11.6% each, five cases of C. dubliniensis (8.3% and four cases of C. tropicalis (6.6% were indicated. The study showed that the sensitivity of C. albicans and C. cruise species to amphotericin B was negligible in disk diffusion and very sensitve in microdilution. Conclusion: Inspite of the results of antifungal susceptibility test of strains studied did not show high resistance, but screening for drug-resistant Candida isolates in Candida infection by disk diffusion and microdilution methods for new cases of drug resistance is reasonable.

  2. Determination of Desorbed Species During Heating of AgI-Mordenite Provided by ORNL

    Energy Technology Data Exchange (ETDEWEB)

    Croes, Kenneth James [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Garino, Terry J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mowry, Curtis D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nenoff, Tina M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-12-15

    This study is focused on describing the desorbed off gases due to heating of the AgIMordenite (MOR) produced at ORNL for iodine (I2) gas capture from nuclear fuel aqueous reprocessing. In particular, the interest is for the incorporation of the AgI-MOR into a waste form, which might be the Sandia developed, low temperature sintering, Bi-Si oxide based, Glass Composite Material (GCM). The GCM has been developed as a waste form for the incorporation any oxide based getter material. In the case where iodine may be released during the sintering process of the GCM, additional Ag flake is added as further insurance in total iodine capture and retention. This has been the case for the incorporated ORNL developed AgIMOR. Thermal analysis studies were carried out to determine off gasing processes of ORNL AgIMOR. Independent of sample size, ~7wt% of total water is desorbed by 225°C. This includes both bulk surface and occluded water, and are monitored as H2O and OH. Of that total, ~5.5wt% is surface water which is removed by 125°C, and 1.5wt% is occluded (in zeolite pore) water. Less than ~1 wt% total water continues to desorb, but is completely removed by 500°C. Above 300°C, the detectable remaining desorbing species observed are iodine containing compounds, including I and I2.

  3. Determination of flavones in species of Thymus L. (Lamiaceae from Macedonian flora

    Directory of Open Access Journals (Sweden)

    Svetlana Kulevanova

    2002-04-01

    Full Text Available Assay of flavonoids in extracts of seven Thymus L. (Lamiaceae species from Macedonia including identification and quantification was performed. Extracts obtained after hydrolysis of air dried samples (A1 were analyzed by thin layer chromatography (TLC and high performance liquid chromatography (HPLC. Luteolin and apigenin were identified in comparison to authentic standard substances. The content of total flavonoids in plant samples determined by UV-Vis spectrometry (with AlCl3 ranged from 0.05-0.13 %. Two other extracts were prepared by extraction with a mixture of ethanol:water (7:3, V/V, evaporation until only water remained and extraction first with diethylether (A2 and secondly with ethyl acetate (A3. The content of flavonoids in diethyl-ether and ethyl acetate extracts ranged from 52.5-244.4 mg·ml-1 and 48.7 -117.5 mg·ml-1, respectively. For quantification of luteolin and total flavonoids the HPLC method was applied, using reverse phase column C18, mobile phase consisting of 5% acetic acid and methanol in gradient elution mode and column temperature set to 40 oC. The content of luteolin in the plant samples ranged from 0.23-0.48 % (m/m, while the content of total flavonoids was found to be 0.26-0.52 %.

  4. Use of DNA from bite marks can determine species and individual animals that attack humans

    Science.gov (United States)

    Farley, Sean; Talbot, Sandra L.; Sage, George K.; Sinnott, Rick; Coltrane, Jessica

    2014-01-01

    During the summer of 2008, 6 documented attacks and close encounters with brown bears (Ursus arctos) occurred in the greater Anchorage, Alaska (USA) area. We discuss findings from 2 incidents in which people were mauled within 2 km of each other over a 6-week period and in which it was assumed that a single animal was responsible. To ensure public safety, authorities killed a brown bear implicated in the attacks by circumstantial evidence, though it was not known a priori that the animal was responsible. We extracted DNA from hairs and bite sites on the clothing of both victims and determined species and individual identity of the animal(s) involved in both incidents. Genetic data indicated the brown bear killed by authorities was responsible for one of the maulings, but not both. This research demonstrates that DNA-based techniques, with appropriate sampling, can provide unambiguous identification of animals involved in attacks, as well as provide reasonable justification for excluding others. Because DNA-based techniques can unequivocally identify individual bears carrying out attacks, they should be considered a standard method employed in wildlife attack investigations.

  5. Opposing effects of floral visitors and soil conditions on the determinants of competitive outcomes maintain species diversity in heterogeneous landscapes.

    Science.gov (United States)

    Lanuza, Jose B; Bartomeus, Ignasi; Godoy, Oscar

    2018-06-01

    Theory argues that both soil conditions and aboveground trophic interactions have equivalent potential to limit or promote plant diversity. However, it remains unexplored how they jointly modify the niche differences stabilising species coexistence and the average fitness differences driving competitive dominance. We conducted a field study in Mediterranean annual grasslands to parameterise population models of six competing plant species. Spatially explicit floral visitor assemblages and soil salinity variation were characterised for each species. Both floral visitors and soil salinity modified species population dynamics via direct changes in seed production and indirect changes in competitive responses. Although the magnitude and sign of these changes were species-specific, floral visitors promoted coexistence at neighbourhood scales, while soil salinity did so over larger scales by changing the superior competitors' identity. Our results show how below and aboveground interactions maintain diversity in heterogeneous landscapes through their opposing effects on the determinants of competitive outcomes. © 2018 John Wiley & Sons Ltd/CNRS.

  6. The application of transition metal ion chromatography to the determination of elemental and radiochemical species in PWR primary coolant

    International Nuclear Information System (INIS)

    Bridle, D.A.; Brown, G.R.; Johnson, P.A.V.

    1992-01-01

    The accurate determination of both elemental and radiochemical transition metal corrosion products, particularly cobalt and nickel, in PWR coolants is necessary if the transport mechanisms and their role in the development of out-of-core radiation fields are to be fully understood. AEA Technology, Winfrith, has collaborated for several years with a number of PWR utilities in Europe, developing advanced sampling and analytical techniques for the determination of both soluble and insoluble corrosion products in primary coolant. The design and installation of continuously flowing isokinetic capillary modifications to the existing sampling systems has been shown to be an effective method of providing a low, but representative, sample flow from high pressure systems for on-line determination of corrosion product species. Transition metal ion chromatography coupled with gamma-spectrometry has been used to determine both insoluble and soluble elemental and radiochemical species in reactor coolant, with particular attention being given to the determination of soluble elemental cobalt at levels as low as 1 ng per kg. Soluble species were determined directly following their concentration from up to 1 litre of coolant. Insoluble species collected on 0.45 micron filter membranes, following filtration of up to 1500 litres of coolant, were solubilised by fusion with potassium hydrogen sulphate before the application of ion chromatography. In each case the eluant from the chromatographic column was collected and the radionuclides determined by gamma-spectrometry

  7. Annual sex steroid and other physiological profiles of Pacific lampreys (Entosphenus tridentatus)

    Science.gov (United States)

    Mesa, Matthew G.; Bayer, Jennifer M.; Bryan, Mara B.; Sower, Stacia A.

    2010-01-01

    We documented changes in plasma levels of estradiol 17-β (E2), progesterone (P), 15α-hydroxytestosterone (15α-T), thyroxine (T4), triiodothyronine (T3), protein, triglycerides (TGs), and glucose in adult Pacific lampreys (Entosphenus tridentatus) held in the laboratory in two different years. Levels of E2 in both sexes ranged from 0.5 to 2 ng/mL from September to March, peaked in late April (2–4 ng/mL), and decreased in May, with levels higher in males than in females. Levels of P were low from September through April, but then increased substantially during May (2–4 ng/mL), with levels again highest in males. Levels of 15α-T in males were around 0.75 ng/mL through the winter before exceeding 1 ng/mL in April and decreasing thereafter, whereas females showed a gradual increase from 0.25 ng/mL in November to 0.5 ng/mL in April before decreasing. Thyroxine concentrations differed between fish in each year, with most having levels ranging from 0.75 to 2.5 ng/mL in the fall and winter, and only fish in 2003 showing distinct peaks (3–4 ng/mL) in early April or May. Plasma T3 was undetectable from November through mid-March before surging dramatically in April (ca. 150 ng/mL) and decreasing thereafter. Levels of protein, TGs, and glucose decreased or were stable during the fall and winter with TGs and glucose surging in late April to early May for some fish. Our study is the first to document long-term physiological changes in Pacific lampreys during overwintering and sexual maturation and increases our understanding of the life history of this unique fish.

  8. A role for tight junction-associated MARVEL proteins in larval sea lamprey (Petromyzon marinus) osmoregulation.

    Science.gov (United States)

    Kolosov, Dennis; Bui, Phuong; Donini, Andrew; Wilkie, Mike P; Kelly, Scott P

    2017-10-15

    This study reports on tight junction-associated MARVEL proteins of larval sea lamprey ( Petromyzon marinus ) and their potential role in ammocoete osmoregulation. Two occludin isoforms (designated Ocln and Ocln-a) and a tricellulin (Tric) were identified. Transcripts encoding ocln , ocln-a and tric were broadly expressed in larval lamprey, with the greatest abundance of ocln in the gut, liver and kidney, ocln-a in the gill and skin, and tric in the kidney. Ocln and Ocln-a resolved as ∼63 kDa and ∼35 kDa MW proteins, respectively, while Tric resolved as a ∼50 kDa protein. Ocln immunolocalized to the gill vasculature and in gill mucous cells while Ocln-a localized to the gill pouch and gill epithelium. Both Ocln and Ocln-a localized in the nephron, the epidermis and the luminal side of the gut. In branchial tissue, Tric exhibited punctate localization, consistent with its presence at regions of tricellular contact. Following ion-poor water (IPW) acclimation of ammocoetes, serum [Na + ] and [Cl - ] decreased, but not [Ca 2+ ], and carcass moisture content increased. In association, Ocln abundance increased in the skin and kidney, but reduced in the gill of IPW-acclimated ammocoetes while Ocln-a abundance reduced in the kidney only. Tric abundance increased in the gill. Region-specific alterations in ocln , ocln-a and tric mRNA abundance were also observed in the gut. Data support a role for Ocln, Ocln-a and Tric in the osmoregulatory strategies of a basal vertebrate. © 2017. Published by The Company of Biologists Ltd.

  9. Female sea lamprey shift orientation toward a conspecific chemical cue to escape a sensory trap

    Science.gov (United States)

    Brant, Cory O.; Johnson, Nicholas; Li, Ke; Buchinger, Tyler J.; Li, Weiming

    2016-01-01

    The sensory trap model of signal evolution hypothesizes that signalers adapt to exploit a cue used by the receiver in another context. Although exploitation of receiver biases can result in conflict between the sexes, deceptive signaling systems that are mutually beneficial drive the evolution of stable communication systems. However, female responses in the nonsexual and sexual contexts may become uncoupled if costs are associated with exhibiting a similar response to a trait in both contexts. Male sea lamprey (Petromyzon marinus) signal with a mating pheromone, 3-keto petromyzonol sulfate (3kPZS), which may be a match to a juvenile cue used by females during migration. Upstream movement of migratory lampreys is partially guided by 3kPZS, but females only move toward 3kPZS with proximal accuracy during spawning. Here, we use in-stream behavioral assays paired with gonad histology to document the transition of female preference for juvenile- and male-released 3kPZS that coincides with the functional shift of 3kPZS as a migratory cue to a mating pheromone. Females became increasingly biased toward the source of synthesized 3kPZS as their maturation progressed into the reproductive phase, at which point, a preference for juvenile odor (also containing 3kPZS naturally) ceased to exist. Uncoupling of female responses during migration and spawning makes the 3kPZS communication system a reliable means of synchronizing mate search. The present study offers a rare example of a transition in female responses to a chemical cue between nonsexual and sexual contexts, provides insights into the origins of stable communication signaling systems.

  10. Using fuzzy logic to determine the vulnerability of marine species to climate change.

    Science.gov (United States)

    Jones, Miranda C; Cheung, William W L

    2018-02-01

    Marine species are being impacted by climate change and ocean acidification, although their level of vulnerability varies due to differences in species' sensitivity, adaptive capacity and exposure to climate hazards. Due to limited data on the biological and ecological attributes of many marine species, as well as inherent uncertainties in the assessment process, climate change vulnerability assessments in the marine environment frequently focus on a limited number of taxa or geographic ranges. As climate change is already impacting marine biodiversity and fisheries, there is an urgent need to expand vulnerability assessment to cover a large number of species and areas. Here, we develop a modelling approach to synthesize data on species-specific estimates of exposure, and ecological and biological traits to undertake an assessment of vulnerability (sensitivity and adaptive capacity) and risk of impacts (combining exposure to hazards and vulnerability) of climate change (including ocean acidification) for global marine fishes and invertebrates. We use a fuzzy logic approach to accommodate the variability in data availability and uncertainties associated with inferring vulnerability levels from climate projections and species' traits. Applying the approach to estimate the relative vulnerability and risk of impacts of climate change in 1074 exploited marine species globally, we estimated their index of vulnerability and risk of impacts to be on average 52 ± 19 SD and 66 ± 11 SD, scaling from 1 to 100, with 100 being the most vulnerable and highest risk, respectively, under the 'business-as-usual' greenhouse gas emission scenario (Representative Concentration Pathway 8.5). We identified 157 species to be highly vulnerable while 294 species are identified as being at high risk of impacts. Species that are most vulnerable tend to be large-bodied endemic species. This study suggests that the fuzzy logic framework can help estimate climate vulnerabilities and risks

  11. Endangered Species

    Science.gov (United States)

    EPA's Endangered Species Protection Program helps promote recovery of listed species. The ESPP determines if pesticide use in a geographic area may affect any listed species. Find needed limits on pesticide use in Endangered Species Protection Bulletins.

  12. Multilevel eEmpirical Bayes modeling for improved estimation of toxicant formulations tosuppress parasitic sea lamprey in the Upper Great Lakes

    Science.gov (United States)

    Hatfield, Laura A.; Gutreuter, Steve; Boogaard, Michael A.; Carlin, Bradley P.

    2011-01-01

    Estimation of extreme quantal-response statistics, such as the concentration required to kill 99.9% of test subjects (LC99.9), remains a challenge in the presence of multiple covariates and complex study designs. Accurate and precise estimates of the LC99.9 for mixtures of toxicants are critical to ongoing control of a parasitic invasive species, the sea lamprey, in the Laurentian Great Lakes of North America. The toxicity of those chemicals is affected by local and temporal variations in water chemistry, which must be incorporated into the modeling. We develop multilevel empirical Bayes models for data from multiple laboratory studies. Our approach yields more accurate and precise estimation of the LC99.9 compared to alternative models considered. This study demonstrates that properly incorporating hierarchical structure in laboratory data yields better estimates of LC99.9 stream treatment values that are critical to larvae control in the field. In addition, out-of-sample prediction of the results of in situ tests reveals the presence of a latent seasonal effect not manifest in the laboratory studies, suggesting avenues for future study and illustrating the importance of dual consideration of both experimental and observational data.

  13. Size of the protected areas is the main determinant of species diversity in orchids

    Czech Academy of Sciences Publication Activity Database

    Schödelbauerová, Iva; Roberts, D.L.; Kindlmann, Pavel

    2009-01-01

    Roč. 142, č. 10 (2009), s. 2329-2334 ISSN 0006-3207 R&D Projects: GA MŠk(CZ) LC06073 Institutional research plan: CEZ:AV0Z60870520 Keywords : NDVI * Orchidaceae * Protected area * Species-area * Species richness Subject RIV: EH - Ecology, Behaviour Impact factor: 3.167, year: 2009

  14. An inverse radiation model for optical determination of temperature and species concentration: Development and validation

    DEFF Research Database (Denmark)

    Ren, Tao; Modest, Michael F.; Fateev, Alexander

    2015-01-01

    2010 (Rothman et al. (2010) [1]), which contains line-by-line (LBL) information for several combustion gas species, such as CO2 and H2O, was used to predict gas spectral transmissivities. The model was validated by retrieving temperatures and species concentrations from experimental CO2 and H2O...

  15. Ecological and economic determinants of invasive tree species on Alabama forestland

    Science.gov (United States)

    Anwar Hussain; Changyou Sun; Xiaoping Zhou; Ian A. Munn

    2008-01-01

    The spread of invasive tree species has caused increasing harm to the environment. This study was motivated by the considerations that earlier studies generally ignored the role of economic factors related to the occurrence and abundance of invasive species, and empirical analyses of invasive trees on forestland have been inadequate. We assessed the impact of...

  16. Determining habitat potential and surveying for nine rare plant species in south-central Utah

    Science.gov (United States)

    Deborah J. Clark; Christine M. Groebner

    2001-01-01

    In south-central Utah, lands within and adjacent to Capitol Reef National Park contain populations of nine rare plant species. In an effort to enhance the combined knowledge about these species, the Bureau of Land Management, the USDA Forest Service, and the National Park Service signed an Interagency Agreement and hired an interagency biologist and field crew to...

  17. Keystone species in seed dispersal networks are mainly determined by dietary specialization

    NARCIS (Netherlands)

    Ribeiro Mello, M.A.; Rodrigues, F.A.; da Fontoura Costa, L.; Kissling, W.D.; Şekercioğlu, Ç.H.; Darcie Marquitti, F.M.; Kalko, E.K.V.

    2015-01-01

    A central issue in ecology is the definition and identification of keystone species, i.e. species that are relatively more important than others for maintaining community structure and ecosystem functioning. Network theory has been pointed out as a robust theoretical framework to enhance the

  18. Survival and metamorphosis of low-density populations of larval sea lampreys (Petromyzon marinus) in streams following lampricide treatment

    Science.gov (United States)

    Johnson, Nicholas S.; Swink, William D.; Brenden, Travis O.; Slade, Jeffrey W.; Steeves, Todd B.; Fodale, Michael F.; Jones, Michael L.

    2014-01-01

    Sea lamprey Petromyzon marinus control in the Great Lakes primarily involves application of lampricides to streams where larval production occurs to kill larvae prior to their metamorphosing and entering the lakes as parasites (juveniles). Because lampricides are not 100% effective, larvae that survive treatment maymetamorphose before streams are again treated. Larvae that survive treatment have not beenwidely studied, so their dynamics are notwell understood.Wetagged and released larvae in six Great Lake tributaries following lampricide treatment and estimated vital demographic rates using multistate tag-recovery models. Model-averaged larval survivals ranged from 56.8 to 57.6%. Model-averaged adult recovery rates, which were the product of juvenile survivals and adult capture probabilities, ranged from 6.8 to 9.3%. Using stochastic simulations, we estimated production of juvenile sea lampreys from a hypothetical population of treatment survivors under different growth conditions based on parameter estimates from this research. For fast-growing populations, juvenile production peaked 2 years after treatment. For slow-growing populations, juvenile production was approximately one-third that of fast-growing populations,with production not peaking until 4 years after treatment. Our results suggest that dynamics (i.e., survival, metamorphosis) of residual larval populations are very similar to those of untreated larval populations. Consequently, residual populations do not necessarily warrant special consideration for the purpose of sea lamprey control and can be ranked for treatment along with other populations. Consecutive lampricide treatments, which are under evaluation by the sea lamprey control program, would bemost effective for reducing juvenile production in large, fast-growing populations.

  19. Pre-Dispersal Seed Predation in a Species-Rich Forest Community: Patterns and the Interplay with Determinants.

    Directory of Open Access Journals (Sweden)

    Yue Xu

    Full Text Available Pre-dispersal seed predation (PDSP is commonly observed in woody plants, and recognized as a driver of seed production variability that is critical for successful regeneration. Earlier studies on PDSP and its determinants were mostly species specific, with community-level PDSP rarely estimated; and the interactions between the temporal variability of seed production and PDSP remain elusive. In this study, the community seed rain of woody plants in a mixed evergreen-deciduous broadleaf forest was monitored for seven years. We examined predation on collected seeds and analyzed the determinants of PDSP. PDSP was recorded in 17 out of 44 woody plant species, and three-quarters of PDSP was due to insect predators. Annual seed production varied substantially at community level, reversely linked with the temporal variation of PDSP rate. The PDSP rate was biased regarding fruit types, and being significantly correlated with seed mass when using phylogenetic independent contrasts (PICs or without taking into account phylogenetic relations, especially for nuts. PDSP rate was also negatively correlated with seed density, showing a threshold-related predator satiation effect. The community-level PDSP rate was primarily determined by tree height, fruit type, and interannual variation of seed production and seed mass. Our analysis revealed a causal link between seed production and the dynamics of PDSP rate at the community level. The predator satiation effect was primarily contributed by the dominant species, whereas the rare species seemed to apply a distinct "hide-and-seek" strategy to control the risk of PDSP. The mechanistic difference of seed production between the common and rare species can shed new light on species coexistence and community assembly. Long-term monitoring of both seed rain and seed predation is required for understanding the ecological and evolutionary implications of species regeneration strategies in a species-rich forest community.

  20. Environmental factors prevail over dispersal constraints in determining the distribution and assembly of Trichoptera species in mountain lakes.

    Science.gov (United States)

    de Mendoza, Guillermo; Ventura, Marc; Catalan, Jordi

    2015-07-01

    Aiming to elucidate whether large-scale dispersal factors or environmental species sorting prevail in determining patterns of Trichoptera species composition in mountain lakes, we analyzed the distribution and assembly of the most common Trichoptera (Plectrocnemia laetabilis, Polycentropus flavomaculatus, Drusus rectus, Annitella pyrenaea, and Mystacides azurea) in the mountain lakes of the Pyrenees (Spain, France, Andorra) based on a survey of 82 lakes covering the geographical and environmental extremes of the lake district. Spatial autocorrelation in species composition was determined using Moran's eigenvector maps (MEM). Redundancy analysis (RDA) was applied to explore the influence of MEM variables and in-lake, and catchment environmental variables on Trichoptera assemblages. Variance partitioning analysis (partial RDA) revealed the fraction of species composition variation that could be attributed uniquely to either environmental variability or MEM variables. Finally, the distribution of individual species was analyzed in relation to specific environmental factors using binomial generalized linear models (GLM). Trichoptera assemblages showed spatial structure. However, the most relevant environmental variables in the RDA (i.e., temperature and woody vegetation in-lake catchments) were also related with spatial variables (i.e., altitude and longitude). Partial RDA revealed that the fraction of variation in species composition that was uniquely explained by environmental variability was larger than that uniquely explained by MEM variables. GLM results showed that the distribution of species with longitudinal bias is related to specific environmental factors with geographical trend. The environmental dependence found agrees with the particular traits of each species. We conclude that Trichoptera species distribution and composition in the lakes of the Pyrenees are governed predominantly by local environmental factors, rather than by dispersal constraints. For

  1. Determining the factors affecting the distribution of Muscari latifolium, an endemic plant of Turkey, and a mapping species distribution model.

    Science.gov (United States)

    Yilmaz, Hatice; Yilmaz, Osman Yalçın; Akyüz, Yaşar Feyza

    2017-02-01

    Species distribution modeling was used to determine factors among the large predictor candidate data set that affect the distribution of Muscari latifolium , an endemic bulbous plant species of Turkey, to quantify the relative importance of each factor and make a potential spatial distribution map of M. latifolium . Models were built using the Boosted Regression Trees method based on 35 presence and 70 absence records obtained through field sampling in the Gönen Dam watershed area of the Kazdağı Mountains in West Anatolia. Large candidate variables of monthly and seasonal climate, fine-scale land surface, and geologic and biotic variables were simplified using a BRT simplifying procedure. Analyses performed on these resources, direct and indirect variables showed that there were 14 main factors that influence the species' distribution. Five of the 14 most important variables influencing the distribution of the species are bedrock type, Quercus cerris density, precipitation during the wettest month, Pinus nigra density, and northness. These variables account for approximately 60% of the relative importance for determining the distribution of the species. Prediction performance was assessed by 10 random subsample data sets and gave a maximum the area under a receiver operating characteristic curve (AUC) value of 0.93 and an average AUC value of 0.8. This study provides a significant contribution to the knowledge of the habitat requirements and ecological characteristics of this species. The distribution of this species is explained by a combination of biotic and abiotic factors. Hence, using biotic interaction and fine-scale land surface variables in species distribution models improved the accuracy and precision of the model. The knowledge of the relationships between distribution patterns and environmental factors and biotic interaction of M. latifolium can help develop a management and conservation strategy for this species.

  2. Determining species expansion and extinction possibilities using probabilistic and graphical models

    Directory of Open Access Journals (Sweden)

    Chaturvedi Rajesh

    2015-03-01

    Full Text Available Survival of plant species is governed by a number of functions. The participation of each function in species survival and the impact of the contrary behaviour of the species vary from function to function. The probability of extinction of species varies in all such scenarios and has to be calculated separately. Secondly, species follow different patterns of dispersal and localisation at different stages of occupancy state of the site, therefore, the scenarios of competition for resources with climatic shifts leading to deterioration and loss of biodiversity resulting in extinction needs to be studied. Furthermore, most possible deviations of species from climax community states needs to be calculated before species become extinct due to sudden environmental disruption. Globally, various types of anthropogenic disturbances threaten the diversity of biological systems. The impact of these anthropogenic activities needs to be analysed to identify extinction patterns with respect to these activities. All the analyses mentioned above have been tried to be achieved through probabilistic or graphical models in this study.

  3. Solar Radiation Determines Site Occupancy of Coexisting Tropical and Temperate Deer Species Introduced to New Zealand Forests.

    Directory of Open Access Journals (Sweden)

    Robert B Allen

    Full Text Available Assemblages of introduced taxa provide an opportunity to understand how abiotic and biotic factors shape habitat use by coexisting species. We tested hypotheses about habitat selection by two deer species recently introduced to New Zealand's temperate rainforests. We hypothesised that, due to different thermoregulatory abilities, rusa deer (Cervus timorensis; a tropical species would prefer warmer locations in winter than red deer (Cervus elaphus scoticus; a temperate species. Since adult male rusa deer are aggressive in winter (the rut, we also hypothesised that rusa deer and red deer would not use the same winter locations. Finally, we hypothesised that in summer both species would prefer locations with fertile soils that supported more plant species preferred as food. We used a 250 × 250 m grid of 25 remote cameras to collect images in a 100-ha montane study area over two winters and summers. Plant composition, solar radiation, and soil fertility were also determined for each camera location. Multiseason occupancy models revealed that direct solar radiation was the best predictor of occupancy and detection probabilities for rusa deer in winter. Multistate, multiseason occupancy models provided strong evidence that the detection probability of adult male rusa deer was greater in winter and when other rusa deer were present at a location. Red deer mostly vacated the study area in winter. For the one season that had sufficient camera images of both species (summer 2011 to allow two-species occupancy models to be fitted, the detection probability of rusa deer also increased with solar radiation. Detection probability also varied with plant composition for both deer species. We conclude that habitat use by coexisting tropical and temperate deer species in New Zealand likely depends on the interplay between the thermoregulatory and behavioural traits of the deer and the abiotic and biotic features of the habitat.

  4. Determination of Cardinal Temperatures for Cool Season Turfgrass and Two Common Weed Species

    Directory of Open Access Journals (Sweden)

    Marjan Diayanat

    2018-02-01

    Full Text Available Introduction The presence of broadleaf weeds not only reduces the aesthetic quality of the turfgrass, but more importantly they compete with desired turfgrass for water, nutrients, and light. Weed management after seeding is an important component to successfully establishing a healthy stand of cool season turfgrass. Weed seed germination is a key process because determines both the number of weeds that could potentially emerge and the timing of their appearance in the turfgrass. Temperature is of the most important factor regulating germination of non-dormant seeds in irrigated, annual agroecosystems at the beginning of the growth season where light, nutrients, and moisture are typically not growth limiting. Also prostrate knotweed (Polygonum aviculare L. and annual sowthistle (Sonchus oleraceus L. are two annual common broad leaf weeds in cool season turfgrass. Prostrate knotweed is very competitive in infertile and compacted soils and often invades turfgrasses along driveways, sidewalks, and beaten paths across lawns. Annual sowthistle is found in open habitats that include waste areas, turf, and roadsides. The aim of this study was to evaluate different nonlinear regression models to describe response of germination rate to different temperatures in perennial ryegrass (Lolium perenne L., fescue (Festuca rubra L., prostrate knotweed and annual sowthistle. Materials and Methods This experiment was based on completely randomized design with 4 replications at Islamic Azad University in the laboratory of Science Research Branch in 2015. The seeds were treated with different temperatures (2, 5, 10, 15, 20, 25, 30, 35, 40 and 45oC Twenty five seeds were placed in each petri dish for each species in per replication. Ten milliliters of distilled water were added to each petri dish and the filter papers were regularly moistened to ensure saturation throughout the germination tests. Petri dishes were placed in germinator with 16 hour day, 8 hour night

  5. Species Distribution modeling as a tool to unravel determinants of palm distribution in Thailand

    DEFF Research Database (Denmark)

    Tovaranonte, Jantrararuk; Barfod, Anders S.; Balslev, Henrik

    2011-01-01

    As a consequence of the decimation of the forest cover in Thailand from 50% to ca. 20 % since the 1950ies, it is difficult to gain insight in the drivers behind past, present and future distribution ranges of plant species. Species distribution modeling allows visualization of potential species...... distribution under specific sets of assumptions. In this study we used maximum entropy to map potential distributions of 103 species of palms for which more than 5 herbarium records exist. Palms constitute key-stone plant group from both an ecological, economical and conservation perspective. The models were......) and the Area Under the Curve (AUC). All models performed well with AUC scores above 0.95. The predicted distribution ranges showed high suitability for palms in the southern region of Thailand. It also shows that spatial predictor variables are important in cases where historical processes may explain extant...

  6. Strongylus asini (Nematoda, Strongyloidea): genetic relationships with other Strongylus species determined by ribosomal DNA.

    Science.gov (United States)

    Hung, G C; Jacobs, D E; Krecek, R C; Gasser, R B; Chilton, N B

    1996-12-01

    Genomic DNA was isolated from adult Strongylus asini collected from zebra. The second ribosomal transcribed spacer (ITS-2) was amplified and sequenced using polymerase chain reaction (PCR) based techniques. The DNA sequence was compared with previously published data for 3 related Strongylus species. A PCR-linked restriction fragment length polymorphism method allowed the 4 species to be differentiated unequivocally. The ITS-2 sequence of S. asini was found to be more similar to those of S. edentatus (87.1%) and S. equinus (95.3%) than to that of S vulgaris (73.9%). This result confirms that S. Asini and S vulgaris represent separate species and supports the retention of the 4 species within 1 genus.

  7. 78 FR 32013 - Endangered and Threatened Wildlife and Plants; Determination of Endangered Status for 38 Species...

    Science.gov (United States)

    2013-05-28

    ... potential for destruction of plants due their proximity to a popular hiking and jeep trail; and habitat... restoration of ecosystem functionality for the recovery of each species, and provide conservation benefits for...

  8. The role of positive selection in determining the molecular cause of species differences in disease

    Directory of Open Access Journals (Sweden)

    Foord Steven M

    2008-10-01

    Full Text Available Abstract Background Related species, such as humans and chimpanzees, often experience the same disease with varying degrees of pathology, as seen in the cases of Alzheimer's disease, or differing symptomatology as in AIDS. Furthermore, certain diseases such as schizophrenia, epithelial cancers and autoimmune disorders are far more frequent in humans than in other species for reasons not associated with lifestyle. Genes that have undergone positive selection during species evolution are indicative of functional adaptations that drive species differences. Thus we investigate whether biomedical disease differences between species can be attributed to positively selected genes. Results We identified genes that putatively underwent positive selection during the evolution of humans and four mammals which are often used to model human diseases (mouse, rat, chimpanzee and dog. We show that genes predicted to have been subject to positive selection pressure during human evolution are implicated in diseases such as epithelial cancers, schizophrenia, autoimmune diseases and Alzheimer's disease, all of which differ in prevalence and symptomatology between humans and their mammalian relatives. In agreement with previous studies, the chimpanzee lineage was found to have more genes under positive selection than any of the other lineages. In addition, we found new evidence to support the hypothesis that genes that have undergone positive selection tend to interact with each other. This is the first such evidence to be detected widely among mammalian genes and may be important in identifying molecular pathways causative of species differences. Conclusion Our dataset of genes predicted to have been subject to positive selection in five species serves as an informative resource that can be consulted prior to selecting appropriate animal models during drug target validation. We conclude that studying the evolution of functional and biomedical disease differences

  9. Determining the Effect of Natural Selection on Linked Neutral Divergence across Species.

    Science.gov (United States)

    Phung, Tanya N; Huber, Christian D; Lohmueller, Kirk E

    2016-08-01

    A major goal in evolutionary biology is to understand how natural selection has shaped patterns of genetic variation across genomes. Studies in a variety of species have shown that neutral genetic diversity (intra-species differences) has been reduced at sites linked to those under direct selection. However, the effect of linked selection on neutral sequence divergence (inter-species differences) remains ambiguous. While empirical studies have reported correlations between divergence and recombination, which is interpreted as evidence for natural selection reducing linked neutral divergence, theory argues otherwise, especially for species that have diverged long ago. Here we address these outstanding issues by examining whether natural selection can affect divergence between both closely and distantly related species. We show that neutral divergence between closely related species (e.g. human-primate) is negatively correlated with functional content and positively correlated with human recombination rate. We also find that neutral divergence between distantly related species (e.g. human-rodent) is negatively correlated with functional content and positively correlated with estimates of background selection from primates. These patterns persist after accounting for the confounding factors of hypermutable CpG sites, GC content, and biased gene conversion. Coalescent models indicate that even when the contribution of ancestral polymorphism to divergence is small, background selection in the ancestral population can still explain a large proportion of the variance in divergence across the genome, generating the observed correlations. Our findings reveal that, contrary to previous intuition, natural selection can indirectly affect linked neutral divergence between both closely and distantly related species. Though we cannot formally exclude the possibility that the direct effects of purifying selection drive some of these patterns, such a scenario would be possible only

  10. Characterizing Species at Risk II: Using Bayesian Belief Networks as Decision Support Tools to Determine Species Conservation Categories Under the Northwest Forest Plan

    Directory of Open Access Journals (Sweden)

    Bruce G. Marcot

    2006-12-01

    Full Text Available We developed a set of decision-aiding models as Bayesian belief networks (BBNs that represented a complex set of evaluation guidelines used to determine the appropriate conservation of hundreds of potentially rare species on federally-administered lands in the Pacific Northwest United States. The models were used in a structured assessment and paneling procedure as part of an adaptive management process that evaluated new scientific information under the Northwest Forest Plan. The models were not prescriptive but helped resource managers and specialists to evaluate complicated and at times conflicting conservation guidelines and to reduce bias and uncertainty in evaluating the scientific data. We concluded that applying the BBN modeling framework to complex and equivocal evaluation guidelines provided a set of clear, intuitive decision-aiding tools that greatly aided the species evaluation and conservation process.

  11. Determining the annual periodicity of growth rings in seven tree species of a tropical moist forest in Santa Cruz, Bolivia

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, L.; Villalba, R.; Pena-Claros, M.

    2012-07-01

    To determine the annual periodicity of growth rings in seven tree species from a tropical moist forest in Santa Cruz, Bolivia, a fire scar was used as a marker point to verify the annual nature of tree rings. The number of tree rings formed between the 1995 fire scar and the collection of the cross sections in 2002 was visually identified. The seven species showed annual growth rings. In most cases, boundaries between rings were marked by the presence of marginal parenchyma and wall-thick ed fibers formed at the end of the growing season. Growth lenses and false rings were recorded in some species. Tree rings can be carefully used in Santa Cruz forests to determine rates of growth. This information is crucial for defining forest management practices in tropical regions. (Author) 21 refs.

  12. Power-Law Kinetics and Determinant Criteria for the Preclusion of Multistationarity in Networks of Interacting Species

    DEFF Research Database (Denmark)

    Wiuf, Carsten Henrik; Feliu, Elisenda

    2013-01-01

    is derived from the determinant of the Jacobian of the species formation rate function. Using this characterization, we further derive similar determinant criteria applicable to general sets of kinetics. The criteria are conceptually simple, computationally tractable, and easily implemented. Our approach...... embraces and extends previous work on multistationarity, such as work in relation to chemical reaction networks with dynamics defined by mass-action or noncatalytic kinetics, and also work based on graphical analysis of the interaction graph associated with the system. Further, we interpret the criteria...... and how the species influence each reaction. We characterize families of so-called power-law kinetics for which the associated species formation rate function is injective within each stoichiometric class and thus the network cannot exhibit multistationarity. The criterion for power-law kinetics...

  13. Evolution of the complementary sex-determination gene of honey bees: balancing selection and trans-species polymorphisms.

    Science.gov (United States)

    Cho, Soochin; Huang, Zachary Y; Green, Daniel R; Smith, Deborah R; Zhang, Jianzhi

    2006-11-01

    The mechanism of sex determination varies substantively among evolutionary lineages. One important mode of genetic sex determination is haplodiploidy, which is used by approximately 20% of all animal species, including >200,000 species of the entire insect order Hymenoptera. In the honey bee Apis mellifera, a hymenopteran model organism, females are heterozygous at the csd (complementary sex determination) locus, whereas males are hemizygous (from unfertilized eggs). Fertilized homozygotes develop into sterile males that are eaten before maturity. Because homozygotes have zero fitness and because common alleles are more likely than rare ones to form homozygotes, csd should be subject to strong overdominant selection and negative frequency-dependent selection. Under these selective forces, together known as balancing selection, csd is expected to exhibit a high degree of intraspecific polymorphism, with long-lived alleles that may be even older than the species. Here we sequence the csd genes as well as randomly selected neutral genomic regions from individuals of three closely related species, A. mellifera, Apis cerana, and Apis dorsata. The polymorphic level is approximately seven times higher in csd than in the neutral regions. Gene genealogies reveal trans-species polymorphisms at csd but not at any neutral regions. Consistent with the prediction of rare-allele advantage, nonsynonymous mutations are found to be positively selected in csd only in early stages after their appearances. Surprisingly, three different hypervariable repetitive regions in csd are present in the three species, suggesting variable mechanisms underlying allelic specificities. Our results provide a definitive demonstration of balancing selection acting at the honey bee csd gene, offer insights into the molecular determinants of csd allelic specificities, and help avoid homozygosity in bee breeding.

  14. Pre-dispersal seed predation in a species-rich forest community: Patterns and the interplay with determinants

    Science.gov (United States)

    Yue Xu; Zehao Shen; Daoxin Li; Qinfeng Guo

    2015-01-01

    Pre-dispersal seed predation (PDSP) is commonly observed in woody plants, and recognized as a driver of seed production variability that is critical for successful regeneration. Earlier studies on PDSP and its determinants were mostly species specific, with community- level PDSP rarely estimated; and the interactions between the temporal...

  15. Local and regional palm (Arecaceae) species richness patterns and their cross-scale determinants in the western Amazon

    DEFF Research Database (Denmark)

    Kristiansen, Thea; Svenning, J.-C.; Pedersen, Dennis

    2011-01-01

    divergent environmental conditions or biogeographic histories. 2. We investigated the cross-scale determinants of palm alpha and gamma diversity across the western Amazon using a large field-based data set: a census of all palm individuals in 312 transects, totalling 98 species. We used regression...

  16. Principal determinants of species and functional diversity of carabid beetle assemblages during succession at post-industrial sites.

    Science.gov (United States)

    Sipos, J; Hodecek, J; Kuras, T; Dolny, A

    2017-08-01

    Although ecological succession is one of the principal focuses of recent restoration ecology research, it is still unclear which factors drive this process and positively influence species richness and functional diversity. In this study we sought to elucidate how species traits and functional diversity change during forest succession, and to identify important factors that determine the species in the observed assemblages. We analyzed species richness and functional diversity of ground beetle assemblages in relation to succession on post-industrial localities after habitat deterioration caused by spoil deposition. We selected ground beetles as they are known to be sensitive to landscape changes (with a large range of responses), and their taxonomy and ecology are generally well-known. Ground beetles were sampled on the spoil heaps during the last 30 years when spontaneous succession occurred. To calculate functional diversity, we used traits related to habitat and trophic niche, i.e. food specialization, wing morphology, trophic level, and bio-indication value. Ground beetle species were found to be distributed non-randomly in the assemblages in the late phase of succession. Ordination analyses revealed that the ground beetle assemblage was significantly associated with the proportion of forested area. Environmental heterogeneity generated assemblages that contained over-dispersed species traits. Our findings indicated that environmental conditions at late successional stages supported less mobile carnivorous species. Overall, we conclude that the decline in species richness and functional diversity in the middle of the studied succession gradient indicated that the assemblages of open habitats had been replaced by species typical of forest ecosystems.

  17. Trait-fitness relationships determine how trade-off shapes affect species coexistence.

    Science.gov (United States)

    Ehrlich, Elias; Becks, Lutz; Gaedke, Ursula

    2017-12-01

    Trade-offs between functional traits are ubiquitous in nature and can promote species coexistence depending on their shape. Classic theory predicts that convex trade-offs facilitate coexistence of specialized species with extreme trait values (extreme species) while concave trade-offs promote species with intermediate trait values (intermediate species). We show here that this prediction becomes insufficient when the traits translate non-linearly into fitness which frequently occurs in nature, e.g., an increasing length of spines reduces grazing losses only up to a certain threshold resulting in a saturating or sigmoid trait-fitness function. We present a novel, general approach to evaluate the effect of different trade-off shapes on species coexistence. We compare the trade-off curve to the invasion boundary of an intermediate species invading the two extreme species. At this boundary, the invasion fitness is zero. Thus, it separates trait combinations where invasion is or is not possible. The invasion boundary is calculated based on measurable trait-fitness relationships. If at least one of these relationships is not linear, the invasion boundary becomes non-linear, implying that convex and concave trade-offs not necessarily lead to different coexistence patterns. Therefore, we suggest a new ecological classification of trade-offs into extreme-favoring and intermediate-favoring which differs from a purely mathematical description of their shape. We apply our approach to a well-established model of an empirical predator-prey system with competing prey types facing a trade-off between edibility and half-saturation constant for nutrient uptake. We show that the survival of the intermediate prey depends on the convexity of the trade-off. Overall, our approach provides a general tool to make a priori predictions on the outcome of competition among species facing a common trade-off in dependence of the shape of the trade-off and the shape of the trait

  18. Site and plant species are important determinants of the Methylobacterium community composition in the plant phyllosphere.

    Science.gov (United States)

    Knief, Claudia; Ramette, Alban; Frances, Lisa; Alonso-Blanco, Carlos; Vorholt, Julia A

    2010-06-01

    The plant phyllosphere constitutes a habitat for numerous microorganisms; among them are members of the genus Methylobacterium. Owing to the ubiquitous occurrence of methylobacteria on plant leaves, they represent a suitable target for studying plant colonization patterns. The influence of the factor site, host plant species, time and the presence of other phyllosphere bacteria on Methylobacterium community composition and population size were evaluated in this study. Leaf samples were collected from Arabidopsis thaliana or Medicago truncatula plants and from the surrounding plant species at several sites. The abundance of cultivable Methylobacterium clearly correlated with the abundance of other phyllosphere bacteria, suggesting that methylobacteria constitute a considerable and rather stable fraction of the phyllosphere microbiota under varying environmental conditions. Automated ribosomal intergenic spacer analysis (ARISA) was applied to characterize the Methylobacterium community composition and showed the presence of similar communities on A. thaliana plants at most sites in 2 consecutive years of sampling. A substantial part of the observed variation in the community composition was explained by site and plant species, especially in the case of the plants collected at the Arabidopsis sites (50%). The dominating ARISA peaks that were detected on A. thaliana plants were found on other plant species grown at the same site, whereas some different peaks were detected on A. thaliana plants from other sites. This indicates that site-specific factors had a stronger impact on the Methylobacterium community composition than did plant-specific factors and that the Methylobacterium-plant association is not highly host plant species specific.

  19. Determinants of bird conservation-action implementation and associated population trends of threatened species.

    Science.gov (United States)

    Luther, David A; Brooks, Thomas M; Butchart, Stuart H M; Hayward, Matt W; Kester, Marieke E; Lamoreux, John; Upgren, Amy

    2016-12-01

    Conservation actions, such as habitat protection, attempt to halt the loss of threatened species and help their populations recover. The efficiency and the effectiveness of actions have been examined individually. However, conservation actions generally occur simultaneously, so the full suite of implemented conservation actions should be assessed. We used the conservation actions underway for all threatened and near-threatened birds of the world (International Union for Conservation of Nature Red List of Threatened Species) to assess which biological (related to taxonomy and ecology) and anthropogenic (related to geoeconomics) factors were associated with the implementation of different classes of conservation actions. We also assessed which conservation actions were associated with population increases in the species targeted. Extinction-risk category was the strongest single predictor of the type of conservation actions implemented, followed by landmass type (continent, oceanic island, etc.) and generation length. Species targeted by invasive nonnative species control or eradication programs, ex situ conservation, international legislation, reintroduction, or education, and awareness-raising activities were more likely to have increasing populations. These results illustrate the importance of developing a predictive science of conservation actions and the relative benefits of each class of implemented conservation action for threatened and near-threatened birds worldwide. © 2016 Society for Conservation Biology.

  20. Determination of the radioiodine species in the exhaust air of nuclear facilities

    International Nuclear Information System (INIS)

    Deuber, H.

    1977-01-01

    Using the selective I 2 sorption materials DSM 10 and DSM 11 measurements were performed with radioiodine species samplers in the exhaust air of a research reactor and of several nuclear power stations (BWR, PWR). The radioiodine species samplers were used upstream and downstream of iodine filters (containment exhaust air stand-by filter, shutoff room exhaust air filter) as well as in the exhaust air of the stack. The results obtained by use of DSM 10 and DSM 11 generally agreed. The percentage of aerosol iodine was low in all cases ( [de

  1. Trace elements in several species of crustaceans of Amami Island Group in Japan determined by activation analysis

    International Nuclear Information System (INIS)

    Fukushima, M.; Tamate, H.; Nakano, Y.

    2001-01-01

    Concentration levels of trace elements were determined in several species of subtropical crustaceans from Amami Islands in Japan in order to evaluate the levels of specific accumulation of elements among species. Tissue samples prepared from gill, muscle, hepatopancreas, and testis were irradiated for photon activation analysis (PAA) and neutron activation analysis (NAA). By PAA and NAA, eighteen elements could be determined. The levels of Br and I were extremely high in gills of spiny lobster and shovel-nosed lobster, respectively. A high concentration of Ag was found in the hepatopancreas of spiny lobsters collected from the Amami Island, while this element was not detected in the same species collected from Toba. The results suggest that the distribution of the trace elements in different tissues and species varies according to both species and environmental differences. To study the molecular forms of the elements in tissue, fractions that contained protein-bound elements from the hepatopancreas of spiny lobsters were separated by ultracentrifugation and gel filtration chromatography. Elution profiles of the chromatography suggest that Cu, Fe, and Se were bound to proteins, while Ag was not. (author)

  2. Seed dormancy responses to temperature relate to Nothofagus species distribution and determine temporal patterns of germination across altitudes in Patagonia.

    Science.gov (United States)

    Arana, María V; Gonzalez-Polo, Marina; Martinez-Meier, Alejandro; Gallo, Leonardo A; Benech-Arnold, Roberto L; Sánchez, Rodolfo A; Batlla, Diego

    2016-01-01

    Seeds integrate environmental cues that modulate their dormancy and germination. Although many mechanisms have been identified in laboratory experiments, their contribution to germination dynamics in existing communities and their involvement in defining species habitats remain elusive. By coupling mathematical models with ecological data we investigated the contribution of seed temperature responses to the dynamics of germination of three Nothofagus species that are sharply distributed across different altitudes in the Patagonian Andes. Seed responsiveness to temperature of the three Nothofagus species was linked to the thermal characteristics of their preferred ecological niche. In their natural distribution range, there was overlap in the timing of germination of the species, which was restricted to mid-spring. By contrast, outside their species distribution range, germination was temporally uncoupled with altitude. This phenomenon was described mathematically by the interplay between interspecific differences in seed population thermal parameters and the range in soil thermic environments across different altitudes. The observed interspecific variations in seed responsiveness to temperature and its environmental regulation, constitute a major determinant of the dynamics of Nothofagus germination across elevations. This phenomenon likely contributes to the maintenance of patterns of species abundance across altitude by placing germinated seeds in a favorable environment for plant growth. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  3. The use of ISSR markers for species determination and a genetic study of the invasive lionfish in Guanahacabibes, Cuba

    Directory of Open Access Journals (Sweden)

    Elizabeth Labastida

    2015-11-01

    Full Text Available The red lionfish (Pterois volitans and devil fire-fish (Pterois miles are invasive species that pose a threat to the biodiversity and stability of coral reefs in the Western Atlantic, Gulf of Mexico and Caribbean Sea. Species identification of lionfish is uncertain in some parts of Cuba, and research has mainly been focused on their biology and ecology. The principal aim of this study was to determine highly polymorphic markers (Inter Simple Sequence Repeat, ISSR that could be used in research on lionfish population genetics in addition to confirming the presence of Pterois species in the Guanahacabibes National Park. The genetic profile or "fingerprint" of individuals collected in Mexico, formally identified as P. volitans, was compared with the genetic profile of specimens from Cuba. There were very few "diagnostic bands" and a high number of "common bands", demonstrating that the same species exists in both countries. Furthermore, Nei's genetic distance and the unrooted tree do not show significant differences between both localities. In light of these results, we can confirm the presence of P. volitans in the Guanahacabibes National Park, Cuba. This study demonstrates the functionality of ISSR as a molecular tool for species identification and their application for genetic population studies of this invasive fish species.

  4. Determination of incoming solar radiation in major tree species in Turkey.

    Science.gov (United States)

    Yilmaz, Osman Yalcin; Sevgi, Orhan; Koc, Ayhan

    2012-07-01

    Light requirements and spatial distribution of major forest tree species in Turkey hasn't been analyzed yet. Continuous surface solar radiation data, especially at mountainous-forested areas, are needed to put forward this relationship between forest tree species and solar radiation. To achieve this, GIS-based modeling of solar radiation is one of the methods used in rangelands to estimate continuous surface solar radiation. Therefore, mean monthly and annual total global solar radiation maps of whole Turkey were computed spatially using GRASS GIS software "r.sun" model under clear-sky (cloudless) conditions. 147498 pure forest stand point-based data were used in the study for calculating mean global solar radiation values of all the major forest tree species of Turkey. Beech had the lowest annual mean total global solar radiation value of 1654.87 kWh m(-2), whereas juniper had the highest value of 1928.89 kWh m(-2). The rank order of tree species according to the mean monthly and annual total global solar radiation values, using a confidence level of p solar radiation values of sites and light requirements of forest trees ranked similarly.

  5. Disturbance Level Determines the Regeneration of Commercial Tree Species in the Eastern Amazon

    NARCIS (Netherlands)

    Schwartz, G.; Lopes, J.C.; Kanashiro, M.; Mohren, G.M.J.; Pena Claros, M.

    2014-01-01

    The effects of reduced-impact logging (RIL) on the regeneration of commercial tree species were investigated, as long-term timber yields depend partly on the availability of seedlings in a managed forest. On four occasions during a 20-month period in the Tapajós National Forest (Eastern Amazon,

  6. Moisture and nutrients determine the distribution and richness of India's large herbivore species assemblage

    NARCIS (Netherlands)

    Ahrestani, F.S.; Heitkonig, I.M.A.; Langevelde, van F.; Vaidyanathan, S.; Madhusudan, M.D.; Prins, H.H.T.

    2011-01-01

    The goal of this study was to test whether body-mass based foraging principles, guided by plant available moisture (PAM) and plant available nutrients (PAN), could explain large mammalian herbivore species distribution and richness in India. We tested (1) whether the occurrence of larger-bodied

  7. Determination of the Ecological and Geographic Distributions of Armillaria Species in Missouri Ozark Forest Ecosystems

    Science.gov (United States)

    Johann N. Bruhn; James J. Wetteroff; Jeanne D. Mihail; Susan. Burks

    1997-01-01

    Armillaria root rot contributes to oak decline in the Ozarks. Three Armillaria species were detected in Ecological Landtypes (ELT's) representing south- to west-facing side slopes (ELT 17), north- to east-facing side slopes (ELT 18), and ridge tops (ELT 11). Armillaria mellea was detected in 91 percent...

  8. Habitat area and climate stability determine geographical variation in plant species range sizes

    DEFF Research Database (Denmark)

    Morueta-Holme, Naia; Enquist, Brian J.; McGill, Brian J.

    2013-01-01

    Despite being a fundamental aspect of biodiversity, little is known about what controls species range sizes. This is especially the case for hyperdiverse organisms such as plants. We use the largest botanical data set assembled to date to quantify geographical variation in range size for ~85,000 ...

  9. 78 FR 58938 - Endangered and Threatened Wildlife and Plants; Determination of Endangered Species Status for the...

    Science.gov (United States)

    2013-09-25

    ... vertical drains, and sedimentation. The species is found only in one county in Missouri and has a... quality because of sedimentation and the presence of chemicals, some of which are of agricultural origin... storage tanks for hazardous waste, that compound potential threats to groundwater and drinking water (Moss...

  10. Evolutionary history determines how plant productivity responds to phylogenetic diversity and species richness

    Directory of Open Access Journals (Sweden)

    Mark A. Genung

    2014-03-01

    Full Text Available The relationship between biodiversity and ecosystem function has received a great deal of attention in ecological research and recent results, from re-analyses, suggest that ecosystem function improves with increases in phylogenetic diversity. However, many of these results have been generalized across a range of different species and clades, and plants with different evolutionary histories could display different relationships between biodiversity and ecosystem function. To experimentally test this hypothesis, we manipulated species richness and phylogenetic diversity using 26 species from two subgenera of the genus Eucalyptus (subgenus Eucalyptus and subgenus Symphyomyrtus. We found that plant biomass (a measurement of ecosystem function sometimes, but not always, responded to increases in species richness and phylogenetic diversity. Specifically, Symphyomyrtus plants showed a positive response while no comparable effect was observed for Eucalyptus plants, showing that responses to biodiversity can vary across different phylogenetic groups. Our results show that the impacts of evolutionary history may complicate the relationship between the diversity of plant communities and plant biomass.

  11. Toxic properties of specific radiation determinant molecules, derived from radiated species

    Science.gov (United States)

    Popov, Dmitri; Maliev, Vecheslav; Kedar, Prasad; Casey, Rachael; Jones, Jeffrey

    Introduction: High doses of radiation induce the formation of radiation toxins in the organs of irradiated mammals. After whole body irradiation, cellular macromolecules and cell walls are damaged as a result of long-lived radiation-induced free radicals, reactive oxygen species, and fast, charged particles of radiation. High doses of radiation induce breaks in the chemical bonds of macromolecules and cross-linking reactions via chemically active processes. These processes result in the creation of novel modified macromolecules that possess specific toxic and antigenic properties defined by the type and dose of irradiation by which they are generated. Radiation toxins isolated from the lymph of irradiated animals are classified as hematotoxic, neurotoxic, and enteric non-bacterial (GI) radiation toxins, and they play an important role in the development of hematopoietic, cerebrovascular, and gastrointestinal acute radiation syndromes (ARS). Seven distinct toxins derived from post-irradiated animals have been designated as Specific Radiation Determinants (SRD): SRD-1 (neurotoxic radiation toxin generated by the cerebrovascular form of ARS), SRD-3 (enteric non-bacterial radiation toxins generated by the gastrointestinal form of ARS), and SRD-4 (hematotoxic radiation toxins generated by the hematological, bone marrow form of ARS). SRD-4 is further subdivided into four groups depending on the severity of the ARS induced: SRD-4/1, mild ARS; SRD-4/2, moderate ARS; SRD-4/3, severe ARS; and SRD-4/4, extremely severe ARS. The seventh SRD, SRD-2 is a toxic extract derived from animals suffering from a fourth form of ARS, as described in European literature and produces toxicity primarily in the autonimic nervous system. These radiation toxins have been shown to be responsible for the induction of important pathophysiological, immunological, and biochemical reactions in ARS. Materials and Methods: These studies incorporated the use of statistically significant numbers of a

  12. Species distribution models contribute to determine the effect of climate and interspecific interactions in moving hybrid zones.

    Science.gov (United States)

    Engler, J O; Rödder, D; Elle, O; Hochkirch, A; Secondi, J

    2013-11-01

    Climate is a major factor delimiting species' distributions. However, biotic interactions may also be prominent in shaping geographical ranges, especially for parapatric species forming hybrid zones. Determining the relative effect of each factor and their interaction of the contact zone location has been difficult due to the lack of broad scale environmental data. Recent developments in species distribution modelling (SDM) now allow disentangling the relative contributions of climate and species' interactions in hybrid zones and their responses to future climate change. We investigated the moving hybrid zone between the breeding ranges of two parapatric passerines in Europe. We conducted SDMs representing the climatic conditions during the breeding season. Our results show a large mismatch between the realized and potential distributions of the two species, suggesting that interspecific interactions, not climate, account for the present location of the contact zone. The SDM scenarios show that the southerly distributed species, Hippolais polyglotta, might lose large parts of its southern distribution under climate change, but a similar gain of novel habitat along the hybrid zone seems unlikely, because interactions with the other species (H. icterina) constrain its range expansion. Thus, whenever biotic interactions limit range expansion, species may become 'trapped' if range loss due to climate change is faster than the movement of the contact zone. An increasing number of moving hybrid zones are being reported, but the proximate causes of movement often remain unclear. In a global context of climate change, we call for more interest in their interactions with climate change. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  13. Determinants of bird species richness, endemism, and island network roles in Wallacea and the West Indies

    DEFF Research Database (Denmark)

    Dalsgaard, Bo; Carstensen, Daniel Wisbech; Fjeldså, Jon

    2014-01-01

    , and network roles indicates that historical climate had little effects on extinction-immigration dynamics. This is in contrast to the strong effect of historical climate observed on the mainland, possibly because surrounding oceans buffer against strong climate oscillations and because geography is a strong....... Here, we evaluate the potential additional effects of historical climate on breeding land bird richness and endemism in Wallacea and the West Indies. Furthermore, on the basis of species distributions, we identify island biogeographical network roles and examine their association with geography......, current and historical climate, and bird richness/endemism. We found that island geography, especially island area but also isolation and elevation, largely explained the variation in island species richness and endemism. Current and historical climate only added marginally to our understanding...

  14. Determination of plant species for the phytoremediation of carbofuran residue in rice field soils

    Directory of Open Access Journals (Sweden)

    Alissara Reungsang

    2005-09-01

    Full Text Available This study searched for plant species suitable for accumulating carbofuran residue in rice field soil. Three groups of plant, i.e. grass crops, upland crops, and vegetable crops, were grown in 8 inches diameter plastic pots filled with soil containing 5 mg/kg carbofuran. Parts of plants (stems and leaves, roots, fruits were harvested at day 120 and analyzed for carbofuran residue using HPLC. The results indicated that Helianthus annuus L. (sunflower was the most suitable species for phytoremediation of carbofuran residue in rice field soil because it highly accumulated carbofuran up to 93.4 μg/kg dry weight in its stems and leaves. In addition, H. annuus L. (sunflower could tolerate carbofuran since it showed similar physical appearance (circumference and height to control not receiving carbofuran.

  15. Advances in modern sample preparation techniques using microwaves assisted chemistry for metal species determination (W1)

    International Nuclear Information System (INIS)

    Ponard, O.F.X.

    2002-01-01

    Full text: Sample preparation has long been the bottleneck of environmental analysis for both total and species specific analysis. Digestion, extraction and preparation of the analytes are relying on a series of chemical reactions. The introduction of microwave assisted sample preparation has first been viewed as a mean to accelerate the kinetics of digestion of the matrix for total elements and fast samples preparation procedures. However, the extensive development and success of microwave digestion procedures in total elemental analysis has now allowed to have a larger insight of the perspectives offered by this technique. Microwave technologies now offer to have a precise control of the temperature and indirectly control the reaction kinetics taking place during the sample preparation procedures. Microwave assisted chemistry permits to perform simultaneously the fundamental steps required for metal species extraction and derivatization. The number of sample preparation steps used for organotin or organomercury species have been reduced to one and the total time of sample preparation brought down for a few hours to some minutes. Further, the developments of GC/ICP/MS techniques allow to routinely use speciated isotopic dilution methods has internal probe of the chemical reactions. These new approaches allow us to use the addition of the labeled species for isotopic dilution as a mean to evaluate and follow the chemical processes taking place during the extraction procedure. These procedures will help us to understand and check for the stability of the analytes during the chemistry of the sample preparation procedure and bring some insights of the chemistry taking place during the extraction. Understanding the different mechanisms involved in the sample preparation steps will allow us in return to further improve all theses procedures and bring us to the horizon of 'on-line sample preparation and detection'. (author)

  16. Identifying Chloris Species from Cuban Citrus Orchards and Determining Their Glyphosate-Resistance Status

    Directory of Open Access Journals (Sweden)

    Enzo R. Bracamonte

    2017-11-01

    Full Text Available The Chloris genus is a C4 photosynthetic species mainly distributed in tropical and subtropical regions. Populations of three Chloris species occurring in citrus orchards from central Cuba, under long history glyphosate-based weed management, were studied for glyphosate-resistant status by characterizing their herbicide resistance/tolerance mechanisms. Morphological and molecular analyses allowed these species to be identified as C. ciliata Sw., Chloris elata Desv., and Chloris barbata Sw. Based on the glyphosate rate that causes 50% mortality of the treated plants, glyphosate resistance (R was confirmed only in C. elata, The R population was 6.1-fold more resistant compared to the susceptible (S population. In addition, R plants of C. elata accumulated 4.6-fold less shikimate after glyphosate application than S plants. Meanwhile, populations of C. barbata and C. ciliata with or without glyphosate application histories showed similar LD50 values and shikimic acid accumulation rates, demonstrating that resistance to glyphosate have not evolved in these species. Plants of R and S populations of C. elata differed in 14C-glyphosate absorption and translocation. The R population exhibited 27.3-fold greater 5-enolpyruvyl shikimate-3-phosphate synthase (EPSPS activity than the S population due to a target site mutation corresponding to a Pro-106-Ser substitution found in the EPSPS gene. These reports show the innate tolerance to glyphosate of C. barbata and C. ciliata, and confirm the resistance of C. elata to this herbicide, showing that both non-target site and target-site mechanisms are involved in its resistance to glyphosate. This is the first case of herbicide resistance in Cuba.

  17. Stand competition determines how different tree species will cope with a warming climate.

    Directory of Open Access Journals (Sweden)

    Laura Fernández-de-Uña

    Full Text Available Plant-plant interactions influence how forests cope with climate and contribute to modulate species response to future climate scenarios. We analysed the functional relationships between growth, climate and competition for Pinus sylvestris, Quercus pyrenaica and Quercus faginea to investigate how stand competition modifies forest sensitivity to climate and simulated how annual growth rates of these species with different drought tolerance would change throughout the 21st century. Dendroecological data from stands subjected to thinning were modelled using a novel multiplicative nonlinear approach to overcome biases related to the general assumption of a linear relationship between covariates and to better mimic the biological relationships involved. Growth always decreased exponentially with increasing competition, which explained more growth variability than climate in Q. faginea and P. sylvestris. The effect of precipitation was asymptotic in all cases, while the relationship between growth and temperature reached an optimum after which growth declined with warmer temperatures. Our growth projections indicate that the less drought-tolerant P. sylvestris would be more negatively affected by climate change than the studied sub-Mediterranean oaks. Q. faginea and P. sylvestris mean growth would decrease under all the climate change scenarios assessed. However, P. sylvestris growth would decline regardless of the competition level, whereas this decrease would be offset by reduced competition in Q. faginea. Conversely, Q. pyrenaica growth would remain similar to current rates, except for the warmest scenario. Our models shed light on the nature of the species-specific interaction between climate and competition and yield important implications for management. Assuming that individual growth is directly related to tree performance, trees under low competition would better withstand the warmer conditions predicted under climate change scenarios but in

  18. Determining the numbers of a landscape architect species (Tapirus terrestris), using footprints.

    Science.gov (United States)

    Moreira, Danielle O; Alibhai, Sky K; Jewell, Zoe C; da Cunha, Cristina J; Seibert, Jardel B; Gatti, Andressa

    2018-01-01

    As a landscape architect and a major seed disperser, the lowland tapir ( Tapirus terrestris ) is an important indicator of the ecological health of certain habitats. Therefore, reliable data regarding tapir populations are fundamental in understanding ecosystem dynamics, including those associated with the Atlantic Forest in Brazil. Currently, many population monitoring studies use invasive tagging with radio or satellite/Global Positioning System (GPS) collars. These techniques can be costly and unreliable, and the immobilization required carries physiological risks that are undesirable particularly for threatened and elusive species such as the lowland tapir. We collected data from one of the last regions with a viable population of lowland tapir in the south-eastern Atlantic Forest, Brazil, using a new non-invasive method for identifying species, the footprint identification technique (FIT). We identified the minimum number of tapirs in the study area and, in addition, we observed that they have overlapping ranges. Four hundred and forty footprints from 46 trails collected from six locations in the study area in a landscape known to contain tapir were analyzed, and 29 individuals were identified from these footprints. We demonstrate a practical application of FIT for lowland tapir censusing. Our study shows that FIT is an effective method for the identification of individuals of a threatened species, even when they lack visible natural markings on their bodies. FIT offers several benefits over other methods, especially for tapir management. As a non-invasive method, it can be used to census or monitor species, giving rapid feedback to managers of protected areas.

  19. Determining the numbers of a landscape architect species (Tapirus terrestris, using footprints

    Directory of Open Access Journals (Sweden)

    Danielle O. Moreira

    2018-03-01

    Full Text Available Background As a landscape architect and a major seed disperser, the lowland tapir (Tapirus terrestris is an important indicator of the ecological health of certain habitats. Therefore, reliable data regarding tapir populations are fundamental in understanding ecosystem dynamics, including those associated with the Atlantic Forest in Brazil. Currently, many population monitoring studies use invasive tagging with radio or satellite/Global Positioning System (GPS collars. These techniques can be costly and unreliable, and the immobilization required carries physiological risks that are undesirable particularly for threatened and elusive species such as the lowland tapir. Methods We collected data from one of the last regions with a viable population of lowland tapir in the south-eastern Atlantic Forest, Brazil, using a new non-invasive method for identifying species, the footprint identification technique (FIT. Results We identified the minimum number of tapirs in the study area and, in addition, we observed that they have overlapping ranges. Four hundred and forty footprints from 46 trails collected from six locations in the study area in a landscape known to contain tapir were analyzed, and 29 individuals were identified from these footprints. Discussion We demonstrate a practical application of FIT for lowland tapir censusing. Our study shows that FIT is an effective method for the identification of individuals of a threatened species, even when they lack visible natural markings on their bodies. FIT offers several benefits over other methods, especially for tapir management. As a non-invasive method, it can be used to census or monitor species, giving rapid feedback to managers of protected areas.

  20. Evidence for determinism in species diversification and contingency in phenotypic evolution during adaptive radiation.

    Science.gov (United States)

    Burbrink, Frank T; Chen, Xin; Myers, Edward A; Brandley, Matthew C; Pyron, R Alexander

    2012-12-07

    Adaptive radiation (AR) theory predicts that groups sharing the same source of ecological opportunity (EO) will experience deterministic species diversification and morphological evolution. Thus, deterministic ecological and morphological evolution should be correlated with deterministic patterns in the tempo and mode of speciation for groups in similar habitats and time periods. We test this hypothesis using well-sampled phylogenies of four squamate groups that colonized the New World (NW) in the Late Oligocene. We use both standard and coalescent models to assess species diversification, as well as likelihood models to examine morphological evolution. All squamate groups show similar early pulses of speciation, as well as diversity-dependent ecological limits on clade size at a continental scale. In contrast, processes of morphological evolution are not easily predictable and do not show similar pulses of early and rapid change. Patterns of morphological and species diversification thus appear uncoupled across these groups. This indicates that the processes that drive diversification and disparification are not mechanistically linked, even among similar groups of taxa experiencing the same sources of EO. It also suggests that processes of phenotypic diversification cannot be predicted solely from the existence of an AR or knowledge of the process of diversification.

  1. Evidence for determinism in species diversification and contingency in phenotypic evolution during adaptive radiation

    Science.gov (United States)

    Burbrink, Frank T.; Chen, Xin; Myers, Edward A.; Brandley, Matthew C.; Pyron, R. Alexander

    2012-01-01

    Adaptive radiation (AR) theory predicts that groups sharing the same source of ecological opportunity (EO) will experience deterministic species diversification and morphological evolution. Thus, deterministic ecological and morphological evolution should be correlated with deterministic patterns in the tempo and mode of speciation for groups in similar habitats and time periods. We test this hypothesis using well-sampled phylogenies of four squamate groups that colonized the New World (NW) in the Late Oligocene. We use both standard and coalescent models to assess species diversification, as well as likelihood models to examine morphological evolution. All squamate groups show similar early pulses of speciation, as well as diversity-dependent ecological limits on clade size at a continental scale. In contrast, processes of morphological evolution are not easily predictable and do not show similar pulses of early and rapid change. Patterns of morphological and species diversification thus appear uncoupled across these groups. This indicates that the processes that drive diversification and disparification are not mechanistically linked, even among similar groups of taxa experiencing the same sources of EO. It also suggests that processes of phenotypic diversification cannot be predicted solely from the existence of an AR or knowledge of the process of diversification. PMID:23034709

  2. Systematic determination of the mosaic structure of bacterial genomes: species backbone versus strain-specific loops

    Directory of Open Access Journals (Sweden)

    Gendrault-Jacquemard A

    2005-07-01

    Full Text Available Abstract Background Public databases now contain multitude of complete bacterial genomes, including several genomes of the same species. The available data offers new opportunities to address questions about bacterial genome evolution, a task that requires reliable fine comparison data of closely related genomes. Recent analyses have shown, using pairwise whole genome alignments, that it is possible to segment bacterial genomes into a common conserved backbone and strain-specific sequences called loops. Results Here, we generalize this approach and propose a strategy that allows systematic and non-biased genome segmentation based on multiple genome alignments. Segmentation analyses, as applied to 13 different bacterial species, confirmed the feasibility of our approach to discern the 'mosaic' organization of bacterial genomes. Segmentation results are available through a Web interface permitting functional analysis, extraction and visualization of the backbone/loops structure of documented genomes. To illustrate the potential of this approach, we performed a precise analysis of the mosaic organization of three E. coli strains and functional characterization of the loops. Conclusion The segmentation results including the backbone/loops structure of 13 bacterial species genomes are new and available for use by the scientific community at the URL: http://genome.jouy.inra.fr/mosaic.

  3. Where to nest? Ecological determinants of chimpanzee nest abundance and distribution at the habitat and tree species scale.

    Science.gov (United States)

    Carvalho, Joana S; Meyer, Christoph F J; Vicente, Luis; Marques, Tiago A

    2015-02-01

    Conversion of forests to anthropogenic land-uses increasingly subjects chimpanzee populations to habitat changes and concomitant alterations in the plant resources available to them for nesting and feeding. Based on nest count surveys conducted during the dry season, we investigated nest tree species selection and the effect of vegetation attributes on nest abundance of the western chimpanzee, Pan troglodytes verus, at Lagoas de Cufada Natural Park (LCNP), Guinea-Bissau, a forest-savannah mosaic widely disturbed by humans. Further, we assessed patterns of nest height distribution to determine support for the anti-predator hypothesis. A zero-altered generalized linear mixed model showed that nest abundance was negatively related to floristic diversity (exponential form of the Shannon index) and positively with the availability of smaller-sized trees, reflecting characteristics of dense-canopy forest. A positive correlation between nest abundance and floristic richness (number of plant species) and composition indicated that species-rich open habitats are also important in nest site selection. Restricting this analysis to feeding trees, nest abundance was again positively associated with the availability of smaller-sized trees, further supporting the preference for nesting in food tree species from dense forest. Nest tree species selection was non-random, and oil palms were used at a much lower proportion (10%) than previously reported from other study sites in forest-savannah mosaics. While this study suggests that human disturbance may underlie the exclusive arboreal nesting at LCNP, better quantitative data are needed to determine to what extent the construction of elevated nests is in fact a response to predators able to climb trees. Given the importance of LCNP as refuge for Pan t. verus our findings can improve conservation decisions for the management of this important umbrella species as well as its remaining suitable habitats. © 2014 Wiley Periodicals, Inc.

  4. Vector status of Aedes species determines geographical risk of autochthonous Zika virus establishment.

    Directory of Open Access Journals (Sweden)

    Lauren Gardner

    2017-03-01

    Full Text Available The 2015-16 Zika virus pandemic originating in Latin America led to predictions of a catastrophic global spread of the disease. Since the current outbreak began in Brazil in May 2015 local transmission of Zika has been reported in over 60 countries and territories, with over 750 thousand confirmed and suspected cases. As a result of its range expansion attention has focused on possible modes of transmission, of which the arthropod vector-based disease spread cycle involving Aedes species is believed to be the most important. Additional causes of concern are the emerging new links between Zika disease and Guillain-Barre Syndrome (GBS, and a once rare congenital disease, microcephaly.Like dengue and chikungunya, the geographic establishment of Zika is thought to be limited by the occurrence of its principal vector mosquito species, Ae. aegypti and, possibly, Ae. albopictus. While Ae. albopictus populations are more widely established than those of Ae. aegypti, the relative competence of these species as a Zika vector is unknown. The analysis reported here presents a global risk model that considers the role of each vector species independently, and quantifies the potential spreading risk of Zika into new regions. Six scenarios are evaluated which vary in the weight assigned to Ae. albopictus as a possible spreading vector. The scenarios are bounded by the extreme assumptions that spread is driven by air travel and Ae. aegypti presence alone and spread driven equally by both species. For each scenario destination cities at highest risk of Zika outbreaks are prioritized, as are source cities in affected regions. Finally, intercontinental air travel routes that pose the highest risk for Zika spread are also ranked. The results are compared between scenarios.Results from the analysis reveal that if Ae. aegypti is the only competent Zika vector, then risk is geographically limited; in North America mainly to Florida and Texas. However, if Ae

  5. Enzyme-assisted extraction and liquid chromatography mass spectrometry for the determination of arsenic species in chicken meat.

    Science.gov (United States)

    Liu, Qingqing; Peng, Hanyong; Lu, Xiufen; Le, X Chris

    2015-08-12

    Chicken is the most consumed meat in North America. Concentrations of arsenic in chicken range from μg kg(-1) to mg kg(-1). However, little is known about the speciation of arsenic in chicken meat. The objective of this research was to develop a method enabling determination of arsenic species in chicken breast muscle. We report here enzyme-enhanced extraction of arsenic species from chicken meat, separation using anion exchange chromatography (HPLC), and simultaneous detection with both inductively coupled plasma mass spectrometry (ICPMS) and electrospray ionization tandem mass spectrometry (ESIMS). We compared the extraction of arsenic species using several proteolytic enzymes: bromelain, papain, pepsin, proteinase K, and trypsin. With the use of papain-assisted extraction, 10 arsenic species were extracted and detected, as compared to 8 detectable arsenic species in the water/methanol extract. The overall extraction efficiency was also improved using a combination of ultrasonication and papain digestion, as compared to the conventional water/methanol extraction. Detection limits were in the range of 1.0-1.8 μg arsenic per kg chicken breast meat (dry weight) for seven arsenic species: arsenobetaine (AsB), inorganic arsenite (As(III)), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), inorganic arsenate (As(V)), 3-nitro-4-hydroxyphenylarsonic acid (Roxarsone), and N-acetyl-4-hydroxy-m-arsanilic acid (NAHAA). Analysis of breast meat samples from six chickens receiving feed containing Roxarsone showed the presence of (mean±standard deviation μg kg(-1)) AsB (107±4), As(III) (113±7), As(V) (7±2), MMA (51±5), DMA (64±6), Roxarsone (18±1), and four unidentified arsenic species (approximate concentration 1-10 μg kg(-1)). Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Interactions between internal forces, body stiffness, and fluid environment in a neuromechanical model of lamprey swimming.

    Science.gov (United States)

    Tytell, Eric D; Hsu, Chia-Yu; Williams, Thelma L; Cohen, Avis H; Fauci, Lisa J

    2010-11-16

    Animal movements result from a complex balance of many different forces. Muscles produce force to move the body; the body has inertial, elastic, and damping properties that may aid or oppose the muscle force; and the environment produces reaction forces back on the body. The actual motion is an emergent property of these interactions. To examine the roles of body stiffness, muscle activation, and fluid environment for swimming animals, a computational model of a lamprey was developed. The model uses an immersed boundary framework that fully couples the Navier-Stokes equations of fluid dynamics with an actuated, elastic body model. This is the first model at a Reynolds number appropriate for a swimming fish that captures the complete fluid-structure interaction, in which the body deforms according to both internal muscular forces and external fluid forces. Results indicate that identical muscle activation patterns can produce different kinematics depending on body stiffness, and the optimal value of stiffness for maximum acceleration is different from that for maximum steady swimming speed. Additionally, negative muscle work, observed in many fishes, emerges at higher tail beat frequencies without sensory input and may contribute to energy efficiency. Swimming fishes that can tune their body stiffness by appropriately timed muscle contractions may therefore be able to optimize the passive dynamics of their bodies to maximize peak acceleration or swimming speed.

  7. The sea lamprey meiotic map improves resolution of ancient vertebrate genome duplications.

    Science.gov (United States)

    Smith, Jeramiah J; Keinath, Melissa C

    2015-08-01

    It is generally accepted that many genes present in vertebrate genomes owe their origin to two whole-genome duplications that occurred deep in the ancestry of the vertebrate lineage. However, details regarding the timing and outcome of these duplications are not well resolved. We present high-density meiotic and comparative genomic maps for the sea lamprey (Petromyzon marinus), a representative of an ancient lineage that diverged from all other vertebrates ∼550 million years ago. Linkage analyses yielded a total of 95 linkage groups, similar to the estimated number of germline chromosomes (1n ∼ 99), spanning a total of 5570.25 cM. Comparative mapping data yield strong support for the hypothesis that a single whole-genome duplication occurred in the basal vertebrate lineage, but do not strongly support a hypothetical second event. Rather, these comparative maps reveal several evolutionarily independent segmental duplications occurring over the last 600+ million years of chordate evolution. This refined history of vertebrate genome duplication should permit more precise investigations of vertebrate evolution. © 2015 Smith and Keinath; Published by Cold Spring Harbor Laboratory Press.

  8. Genetic engineering of chimeric antigen receptors using lamprey derived variable lymphocyte receptors

    Directory of Open Access Journals (Sweden)

    Robert Moot

    2016-01-01

    Full Text Available Chimeric antigen receptors (CARs are used to redirect effector cell specificity to selected cell surface antigens. Using CARs, antitumor activity can be initiated in patients with no prior tumor specific immunity. Although CARs have shown promising clinical results, the technology remains limited by the availability of specific cognate cell target antigens. To increase the repertoire of targetable tumor cell antigens we utilized the immune system of the sea lamprey to generate directed variable lymphocyte receptors (VLRs. VLRs serve as membrane bound and soluble immune effectors analogous but not homologous to immunoglobulins. They have a fundamentally different structure than immunoglobulin (Ig-based antibodies while still demonstrating high degrees of specificity and affinity. To test the functionality of VLRs as the antigen recognition domain of CARs, two VLR-CARs were created. One contained a VLR specific for a murine B cell leukemia and the other contained a VLR specific for the human T cell surface antigen, CD5. The CAR design consisted of the VLR sequence, myc-epitope tag, CD28 transmembrane domain, and intracellular CD3ζ signaling domain. We demonstrate proof of concept, including gene transfer, biosynthesis, cell surface localization, and effector cell activation for multiple VLR-CAR designs. Therefore, VLRs provide an alternative means of CAR-based cancer recognition.

  9. Simultaneous multi-species determination of trimethyllead, monomethylmercury and three butyltin compounds by species-specific isotope dilution GC-ICP-MS in biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Poperechna, Nataliya; Heumann, Klaus G. [Johannes Gutenberg-University Mainz (Germany). Institute of Inorganic Chemistry and Analytical Chemistry

    2005-09-01

    An accurate and sensitive multi-species species-specific isotope dilution GC-ICP-MS method was developed for the simultaneous determination of trimethyllead (Me{sub 3}Pb{sup +}), monomethylmercury (MeHg{sup +}) and the three butyltin species Bu{sub 3}Sn{sup +}, Bu{sub 2}Sn{sup 2+}, and BuSn{sup 3+} in biological samples. The method was validated by three biological reference materials (CRM 477, mussel tissue certified for butyltins; CRM 463, tuna fish certified for MeHg{sup +}; DORM 2, dogfish muscle certified for MeHg{sup +}). Under certain conditions, and with minor modifications of the sample pretreatment procedure, this method could also be transferred to environmental samples such as sediments, as demonstrated by analyzing sediment reference material BCR 646 (freshwater sediment, certified for butyltins). The detection limits of the multi-species GC-ICP-IDMS method for biological samples were 1.4 ng g{sup -1} for MeHg{sup +}, 0.06 ng g{sup -1} for Me{sub 3}Pb{sup +}, 0.3 ng g{sup -1} for BuSn{sup 3+} and Bu{sub 3}Sn{sup +}, and 1.2 ng g{sup -1} for Bu{sub 2}Sn{sup 2+}. Because of the high relevance of these heavy metal alkyl species to the quality assurance of seafood, the method was also applied to corresponding samples purchased from a supermarket. The methylated lead fraction in these samples, correlated to total lead, varied over a broad range (from 0.01% to 7.6%). On the other hand, the MeHg{sup +} fraction was much higher, normally in the range of 80-100%. Considering that we may expect tighter legislative limitations on MeHg{sup +} levels in seafood in the future, we found the highest methylmercury contents (up to 10.6 {mu}g g{sup -1}) in two shark samples, an animal which is at the end of the marine food chain, whereas MeHg{sup +} contents of less than 0.2 {mu}g g{sup -1} were found in most other seafood samples; these results correlate with the idea that MeHg{sup +} is usually of biological origin in the marine environment. The concentration of

  10. Open focused microwave-assisted sample preparation for rapid total and mercury species determination in environmental solid samples

    OpenAIRE

    Tseng, C. M.; Garraud, H.; Amouroux, D.; Donard, O. F. X.; de Diego, A.

    1998-01-01

    This paper describes rapid, simple microwave-assisted leaching/ digestion procedures for total and mercury species determination in sediment samples and biomaterials. An open focused microwave system allowed the sample preparation time to be dramatically reduced to only 24 min when a power of 40-80 W was applied. Quantitative leaching of methylmercury from sediments by HNO3 solution and complete dissolution of biomaterials by an alkaline solution, such as 25% TMAH solution, were obtained. Met...

  11. An approach for identification and determination of arsenic species in the extract of kelp.

    Science.gov (United States)

    Yu, Lee L; Wei, Chao; Zeisler, Rolf; Tong, Junting; Oflaz, Rabia; Bao, Haixia; Wang, Jun

    2015-05-01

    The National Institute of Standards and Technology is developing a kelp powder standard reference material (SRM) in support of dietary supplement measurements. Edible seaweeds such as kelp and laver consumed as diet or dietary supplement contain tens of mg/kg arsenic. The speciation information of arsenic in the seaweed should be provided because the total arsenic alone does not fully address the safety issue of the dietary supplement as the value assignment is originally intended. The inability to avail all arsenic species for value assignment measurements prevented the certification of arsenic species in the candidate SRM; however, approximately 70 % of total arsenic extracted with a 1:1 volume fraction of methanol:water mixture allowed arsenic speciation values to be assigned to a procedure-defined extract, which may be used for method validation in research to improve upon current extraction and measurement practices. Arsenic species in kelp and laver were identified using electrospray ionization ion trap time of flight mass spectrometry (ESI-IT-TOF). Arsenosugars As(328), As(482), and As(392) were found in the kelp candidate SRM while As(328) and As(482) were found in GBW 08521, a certified reference material (CRM) of laver produced by the National Institute of Metrology of China (NIM). A discovery that the digests of kelp and laver contained only dimethylarsinic acid led to the conclusion that the seaweeds did not contain detectible levels of arsenobetaine, arsenocholine or trimethylarsine oxide that could overlap with the peaks of arsenosugars in the separation. The mean ± s of (5.68 ± 0.28) mg/kg and (13.43 ± 0.31) mg/kg found for As(482) and As(392) in kelp, respectively, using instrumental neutron activation analysis (INAA) demonstrated that value assignment measurement of arsenosugars was possible without arsenosugar calibration standards.

  12. The determination and analysis of site-specific rates of mitochondrial reactive oxygen species production

    DEFF Research Database (Denmark)

    Quinlan, Casey L; Perevoschikova, Irina V; Goncalves, Renata L S

    2013-01-01

    Mitochondrial reactive oxygen species (ROS) are widely implicated in physiological and pathological pathways. We propose that it is critical to understand the specific sites of mitochondrial ROS production and their mechanisms of action. Mitochondria possess at least eight distinct sites of ROS...... production in the electron transport chain and matrix compartment. In this chapter, we describe the nature of the mitochondrial ROS-producing machinery and the relative capacities of each site. We provide detailed methods for the measurement of H2O2 release and the conditions under which maximal rates from...

  13. Multiband modulation spectroscopy for determination of sex and species of mosquitoes in flight

    DEFF Research Database (Denmark)

    Gebru, Alem; Jansson, Samuel; Ignell, Rickard

    2018-01-01

    We present a dual-wavelength polarimetric measurement method to distinguish species and sexes of disease transmitting mosquitoes in flight. By measuring co- and de-polarized backscattered light at 808 and 1550 nm, the degree of linear polarization, wingbeat frequency, reflectance, spectral ratio...... and glossiness of mosquitoes can be retrieved. Body and wing contributions to these signals can be separated. Whereas the optical cross-section is sensitive to the aspect of observation, thus the heading direction of the insect in flight, we demonstrate that polarimetric- and spectral- band ratios are largely...

  14. Molecular Determinants of the Thickened Matrix in a Dual-Species Pseudomonas aeruginosa and Enterococcus faecalis Biofilm.

    Science.gov (United States)

    Lee, Keehoon; Lee, Kang-Mu; Kim, Donggeun; Yoon, Sang Sun

    2017-11-01

    Biofilms are microbial communities that inhabit various surfaces and are surrounded by extracellular matrices (ECMs). Clinical microbiologists have shown that the majority of chronic infections are caused by biofilms, following the introduction of the first biofilm infection model by J. W. Costerton and colleagues (J. Lam, R. Chan, K. Lam, and J. W. Costerton, Infect Immun 28:546-556, 1980). However, treatments for chronic biofilm infections are still limited to surgical removal of the infected sites. Pseudomonas aeruginosa and Enterococcus faecalis are two frequently identified bacterial species in biofilm infections; nevertheless, the interactions between these two species, especially during biofilm growth, are not clearly understood. In this study, we observed phenotypic changes in a dual-species biofilm of P. aeruginosa and E. faecalis , including a dramatic increase in biofilm matrix thickness. For clear elucidation of the spatial distribution of the dual-species biofilm, P. aeruginosa and E. faecalis were labeled with red and green fluorescence, respectively. E. faecalis was located at the lower part of the dual-species biofilm, while P. aeruginosa developed a structured biofilm on the upper part. Mutants with altered exopolysaccharide (EPS) productions were constructed in order to determine the molecular basis for the synergistic effect of the dual-species biofilm. Increased biofilm matrix thickness was associated with EPSs, not extracellular DNA. In particular, Pel and Psl contributed to interspecies and intraspecies interactions, respectively, in the dual-species P. aeruginosa and E. faecalis biofilm. Accordingly, targeting Pel and Psl might be an effective part of eradicating P. aeruginosa polymicrobial biofilms. IMPORTANCE Chronic infection is a serious problem in the medical field. Scientists have observed that chronic infections are closely associated with biofilms, and the vast majority of infection-causing biofilms are polymicrobial. Many studies

  15. Determination of the swelling velocity of different wood species and tissues depending on the cutting direction on microtome section level

    Science.gov (United States)

    Stuckenberg, Peter; Wenderdel, Christoph; Zauer, Mario

    2018-06-01

    Swelling velocity in dependence on the anatomical cutting direction of yew [Taxus baccata L.] and boxwood [Buxus sempervirens L.] was determined at temperature of 20 °C and at relative humidity of 10% and 100%. The investigations, conducted on a microtome section level, showed a similar behaviour for specimens of both wood species. It was possible to determine that the swelling velocity for yew and boxwood increases in its anatomical cutting directions. The longitudinal direction showed the lowest value, the tangential direction, by distinction, the highest value. Furthermore, a significant influence of early wood and late wood content on the swelling velocity for yew was detected.

  16. The Escherichia coli BtuE protein functions as a resistance determinant against reactive oxygen species.

    Directory of Open Access Journals (Sweden)

    Felipe A Arenas

    2011-01-01

    Full Text Available This work shows that the recently described Escherichia coli BtuE peroxidase protects the bacterium against oxidative stress that is generated by tellurite and by other reactive oxygen species elicitors (ROS. Cells lacking btuE (ΔbtuE displayed higher sensitivity to K(2TeO(3 and other oxidative stress-generating agents than did the isogenic, parental, wild-type strain. They also exhibited increased levels of cytoplasmic reactive oxygen species, oxidized proteins, thiobarbituric acid reactive substances, and lipoperoxides. E. coli ΔbtuE that was exposed to tellurite or H(2O(2 did not show growth changes relative to wild type cells either in aerobic or anaerobic conditions. Nevertheless, the elimination of btuE from cells deficient in catalases/peroxidases (Hpx(- resulted in impaired growth and resistance to these toxicants only in aerobic conditions, suggesting that BtuE is involved in the defense against oxidative damage. Genetic complementation of E. coli ΔbtuE restored toxicant resistance to levels exhibited by the wild type strain. As expected, btuE overexpression resulted in decreased amounts of oxidative damage products as well as in lower transcriptional levels of the oxidative stress-induced genes ibpA, soxS and katG.

  17. [Determination of five arsenic species in rice by liquid chromatography-inductively coupled plasma-mass spectrometry].

    Science.gov (United States)

    Gong, Jiadi; Cao, Xiaolin; Cao, Zhaoyun; Bian, Yingfang; Yu, Shasha; Chen, Mingxue

    2014-07-01

    A method was developed for the simultaneous determination of arsenic acid [As (V)], arsenious acid [As (III)], arsenobetaine (AsB), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) in rice by liquid chromatography-inductively coupled plasma-mass spectrometry (LC-ICP-MS). The extraction reagent was 0.3 mol/L nitric acid with heat-assistant condition for 1.5 h at 95 degrees C. Then, the five arsenic species were separated by an anion exchange column (Dionex IonPac AS19, 250 mm x 4 mm) and detected by ICP-MS. Four kinds of extracted solutions were compared through the extraction efficiency. The concentration of nitric acid, the temperature and the extraction time were optimized. The recoveries of the five arsenic species spiked in rice at two levels ranged from 89.6% to 99.5% with the relative standard deviations (RSDs, n = 5) of 0.6% - 3.6%. The measured values of the arsenic species in standard rice materials were consistent with their standard values. The linear ranges were 0.05 - 200 microg/L for AsB and DMA, 0.10-400 microg/L for As (III) and MMA, 0.15-600 microg/L for As (V). The limits of detection for the five arsenic species were 0.15-0.45 microg/kg. The results showed that the method is much more precise for the risk assessment of the rice. This method is simple, accurate and durable for the determination of arsenic species in rice.

  18. HPLC-HG-AFS determination of arsenic species in acute promyelocytic leukemia (APL) plasma and blood cells.

    Science.gov (United States)

    Guo, Meihua; Wang, Wenjing; Hai, Xin; Zhou, Jin

    2017-10-25

    Arsenic trioxide (ATO) has been successfully used in the treatment of acute promyelocytic leukemia (APL). To clarify the arsenic species in APL patients, high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry (HPLC-HG-AFS) and HG-AFS methods were developed and validated to quantify the plasma concentrations of inorganic arsenic (As(III) and As(V)) and methylated metabolites (MMA and DMA), and the total amounts of arsenic in blood cells and plasma. Blood cells and plasma were digested with mixtures of HNO 3 H 2 O 2 and analyzed by HG-AFS. For arsenic speciation, plasma samples were prepared with perchloric acid to precipitate protein. The supernatant was separated on an anion-exchange column within 6min with isocratic elution using 13mM CH 3 COONa, 3mM NaH 2 PO 4 , 4mM KNO 3 and 0.2mM EDTA-2Na. The methods provided linearity range of 0.2-20ng/mL for total arsenic and 2.0-50ng/mL for four arsenic species. The developed methods for total arsenic and arsenic species determination were precise and accurate. The spiked recoveries ranged from 81.2%-108.6% and the coefficients of variation for intra- and inter-batch precision were less than 9.3% and 12.5%, respectively. The developed methods were applied successfully for the assay of total arsenic and arsenic species in 5 APL patients. The HPLC-HG-AFS may be a good alternative for arsenic species determination in APL patients with its simplicity and low-cost in comparison with HPLC-ICP-MS. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Determination of seed viability of eight wild Saudi Arabian species by germination and X-ray tests.

    Science.gov (United States)

    Al-Turki, Turki A; Baskin, Carol C

    2017-05-01

    Our purpose was to evaluate the usefulness of the germination vs. the X-ray test in determining the initial viability of seeds of eight wild species ( Salvia spinosa , Salvia aegyptiaca , Ochradenus baccatus , Ochradenus arabicus , Suaeda aegyptiaca , Suaeda vermiculata , Prosopisfarcta and Panicumturgidum ) from Saudi Arabia. Several days were required to determine viability of all eight species via germination tests, while immediate results on filled/viable seeds were obtained with the X-ray test. Seeds of all the species, except Sa.aegyptiaca , showed high viability in both the germination (98-70% at 25/15 °C, 93-66% at 35/25 °C) and X-ray (100-75%) test. Furthermore, there was general agreement between the germination (10% at 25/15 °C and 8% at 35/25 °C) and X-ray (5%) tests that seed viability of Sa.aegyptiaca was very low, and X-ray analysis revealed that this was due to poor embryo development. Seeds of P.farcta have physical dormancy, which was broken by scarification in concentrated sulfuric acid (10 min), and they exhibited high viability in both the germination (98% at 25/15 °C and 93% at 35/25 °C) and X-ray (98%) test. Most of the nongerminated seeds of the eight species except those of Sa.aegyptiaca were alive as judged by the tetrazolium test (TZ). Thus, for the eight species examined, the X-ray test was a good and rapid predictor of seed viability.

  20. Carbon nanotubes as solid-phase extraction sorbents prior to atomic spectrometric determination of metal species: A review

    Energy Technology Data Exchange (ETDEWEB)

    Herrero Latorre, C., E-mail: carlos.herrero@usc.es [Universidad de Santiago de Compostela, Dpto. Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Alfonso X el Sabio s/n, 27002 Lugo (Spain); Alvarez Mendez, J.; Barciela Garcia, J.; Garcia Martin, S.; Pena Crecente, R.M. [Universidad de Santiago de Compostela, Dpto. Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Alfonso X el Sabio s/n, 27002 Lugo (Spain)

    2012-10-24

    Highlights: Black-Right-Pointing-Pointer The use of CNTs as sorbent for metal species in solid phase extraction has been described. Black-Right-Pointing-Pointer Physical and chemical strategies for functionalization of carbon nanotubes have been discussed. Black-Right-Pointing-Pointer Published analytical methods concerning solid phase extraction and atomic spectrometric determination have been reviewed. - Abstract: New materials have significant impact on the development of new methods and instrumentation for chemical analysis. From the discovery of carbon nanotubes in 1991, single and multi-walled carbon nanotubes - due to their high adsorption and desorption capacities - have been employed as sorption substrates in solid-phase extraction for the preconcentration of metal species from diverse matrices. Looking for successive improvements in sensitivity and selectivity, in the past few years, carbon nanotubes have been utilized as sorbents for solid phase extraction in three different ways: like as-grown, oxidized and functionalized nanotubes. In the present paper, an overview of the recent trends in the use of carbon nanotubes for solid phase extraction of metal species in environmental, biological and food samples is presented. The determination procedures involved the adsorption of metals on the nanotube surface, their quantitative desorption and subsequent measurement by means of atomic spectrometric techniques such as flame atomic absorption spectrometry, electrothermal atomic absorption spectrometry or inductively coupled plasma atomic emission spectrometry/mass spectrometry, among others. Synthesis, purification and types of carbon nanotubes, as well as the diverse chemical and physical strategies for their functionalization are described. Based on 140 references, the performance and general properties of the applications of solid phase extraction based on carbon nanotubes for metal species atomic spectrometric determination are discussed.

  1. Carbon nanotubes as solid-phase extraction sorbents prior to atomic spectrometric determination of metal species: A review

    International Nuclear Information System (INIS)

    Herrero Latorre, C.; Álvarez Méndez, J.; Barciela García, J.; García Martín, S.; Peña Crecente, R.M.

    2012-01-01

    Highlights: ► The use of CNTs as sorbent for metal species in solid phase extraction has been described. ► Physical and chemical strategies for functionalization of carbon nanotubes have been discussed. ► Published analytical methods concerning solid phase extraction and atomic spectrometric determination have been reviewed. - Abstract: New materials have significant impact on the development of new methods and instrumentation for chemical analysis. From the discovery of carbon nanotubes in 1991, single and multi-walled carbon nanotubes – due to their high adsorption and desorption capacities – have been employed as sorption substrates in solid-phase extraction for the preconcentration of metal species from diverse matrices. Looking for successive improvements in sensitivity and selectivity, in the past few years, carbon nanotubes have been utilized as sorbents for solid phase extraction in three different ways: like as-grown, oxidized and functionalized nanotubes. In the present paper, an overview of the recent trends in the use of carbon nanotubes for solid phase extraction of metal species in environmental, biological and food samples is presented. The determination procedures involved the adsorption of metals on the nanotube surface, their quantitative desorption and subsequent measurement by means of atomic spectrometric techniques such as flame atomic absorption spectrometry, electrothermal atomic absorption spectrometry or inductively coupled plasma atomic emission spectrometry/mass spectrometry, among others. Synthesis, purification and types of carbon nanotubes, as well as the diverse chemical and physical strategies for their functionalization are described. Based on 140 references, the performance and general properties of the applications of solid phase extraction based on carbon nanotubes for metal species atomic spectrometric determination are discussed.

  2. Advanced functional materials in solid phase extraction for ICP-MS determination of trace elements and their species - A review.

    Science.gov (United States)

    He, Man; Huang, Lijin; Zhao, Bingshan; Chen, Beibei; Hu, Bin

    2017-06-22

    For the determination of trace elements and their species in various real samples by inductively coupled plasma mass spectrometry (ICP-MS), solid phase extraction (SPE) is a commonly used sample pretreatment technique to remove complex matrix, pre-concentrate target analytes and make the samples suitable for subsequent sample introduction and measurements. The sensitivity, selectivity/anti-interference ability, sample throughput and application potential of the methodology of SPE-ICP-MS are greatly dependent on SPE adsorbents. This article presents a general overview of the use of advanced functional materials (AFMs) in SPE for ICP-MS determination of trace elements and their species in the past decade. Herein the AFMs refer to the materials featuring with high adsorption capacity, good selectivity, fast adsorption/desorption dynamics and satisfying special requirements in real sample analysis, including nanometer-sized materials, porous materials, ion imprinting polymers, restricted access materials and magnetic materials. Carbon/silica/metal/metal oxide nanometer-sized adsorbents with high surface area and plenty of adsorption sites exhibit high adsorption capacity, and porous adsorbents would provide more adsorption sites and faster adsorption dynamics. The selectivity of the materials for target elements/species can be improved by using physical/chemical modification, ion imprinting and restricted accessed technique. Magnetic adsorbents in conventional batch operation offer unique magnetic response and high surface area-volume ratio which provide a very easy phase separation, greater extraction capacity and efficiency over conventional adsorbents, and chip-based magnetic SPE provides a versatile platform for special requirement (e.g. cell analysis). The performance of these adsorbents for the determination of trace elements and their species in different matrices by ICP-MS is discussed in detail, along with perspectives and possible challenges in the future

  3. Ecological multiplex interactions determine the role of species for parasite spread amplification.

    Science.gov (United States)

    Stella, Massimo; Selakovic, Sanja; Antonioni, Alberto; Andreazzi, Cecilia

    2018-04-23

    Despite their potential interplay, multiple routes of many disease transmissions are often investigated separately. As an unifying framework for understanding parasite spread through interdependent transmission paths, we present the 'ecomultiplex' model, where the multiple transmission paths among a diverse community of interacting hosts are represented as a spatially explicit multiplex network. We adopt this framework for designing and testing potential control strategies for T. cruzi spread in two empirical host communities. We show that the ecomultiplex model is an efficient and low data-demanding method to identify which species enhances parasite spread and should thus be a target for control strategies. We also find that the interplay between predator-prey and host-parasite interactions leads to a phenomenon of parasite amplification, in which top predators facilitate T. cruzi spread, offering a mechanistic interpretation of previous empirical findings. Our approach can provide novel insights in understanding and controlling parasite spreading in real-world complex systems. © 2018, Stella et al.

  4. Species analysis of organomercury compounds to determine their biopathways at contaminated sites

    International Nuclear Information System (INIS)

    Hintelmann, H.

    1993-01-01

    The environmental behavior of organomercury compounds with special regard to methyl-mercury(II) was investigated. Organomercury species were extraced with a solution of dithizone in chloroform whereas methylmercury(II) is also extractable using HCl/Toluol. A newly developed HPLC/AFS-system was used as the analytical method. The methylmercury(II) content in river Elbe sediments is controlled by the content of sulfidic sulfur. The crucial point for the formation of methylmercury(II) is the microbial activity in the sediments. Besides methylmercury(II) ethylmercury(II) was found in river Koesseine sediments (Marktredwitz). Microbial biofilms are capable of accumulating methylmercury(II) to a factor of 10 5 when compared to the culture solution. (orig.). 62 figs., 47 tabs [de

  5. Geographical, Temporal and Environmental Determinants of Bryophyte Species Richness in the Macaronesian Islands

    Science.gov (United States)

    Aranda, Silvia C.; Gabriel, Rosalina; Borges, Paulo A. V.; Santos, Ana M. C.; de Azevedo, Eduardo Brito; Patiño, Jairo; Hortal, Joaquín; Lobo, Jorge M.

    2014-01-01

    Species richness on oceanic islands has been related to a series of ecological factors including island size and isolation (i.e. the Equilibrium Model of Island Biogeography, EMIB), habitat diversity, climate (i.e., temperature and precipitation) and more recently island ontogeny (i.e. the General Dynamic Model of oceanic island biogeography, GDM). Here we evaluate the relationship of these factors with the diversity of bryophytes in the Macaronesian region (Azores, Madeira, Canary Islands and Cape Verde). The predictive power of EMIB, habitat diversity, climate and the GDM on total bryophyte richness, as well as moss and liverwort richness (the two dominant bryophyte groups), was evaluated through ordinary least squares regressions. After choosing the best subset of variables using inference statistics, we used partial regression analyses to identify the independent and shared effects of each model. The variables included within each model were similar for mosses and liverworts, with orographic mist layer being one of the most important predictors of richness. Models combining climate with either the GDM or habitat diversity explained most of richness variation (up to 91%). There was a high portion of shared variance between all pairwise combinations of factors in mosses, while in liverworts around half of the variability in species richness was accounted for exclusively by climate. Our results suggest that the effects of climate and habitat are strong and prevalent in this region, while geographical factors have limited influence on Macaronesian bryophyte diversity. Although climate is of great importance for liverwort richness, in mosses its effect is similar to or, at least, indiscernible from the effect of habitat diversity and, strikingly, the effect of island ontogeny. These results indicate that for highly vagile taxa on oceanic islands, the dispersal process may be less important for successful colonization than the availability of suitable ecological

  6. Liquid chromatographic determination of para-toluenesulfonamide in edible fillet tissues from three species of fish

    Science.gov (United States)

    Meinertz, J.R.; Schmidt, L.J.; Stehly, G.R.; Gingerich, W.H.

    1999-01-01

    Chloramine-T (N-sodium-N-chloro-p-toluene-sulfonamide) is a candidate therapeutic drug for treating bacterial gill disease, a predominant disease of a variety of fish species. Research has been initiated to obtain the U.S. Food and Drug Administration's (FDA) approval for the use of chloramine-T on a variety of fish species. An attribute of a therapeutic aquaculture drug that must be characterized before the FDA approves its use is depletion of the drug's marker residue (the drug's parent compound or metabolite of highest concentration in an edible tissue). Para-Toluenesulfonamide (p-TSA) is the primary degradation product and marker residue for chloramine-T in rainbow trout. To conduct residue depletion studies for chloramine-T in fish, a robust analytical method sensitive and specific for p-TSA residues in edible fillet tissue from a variety of fish was required. Homogenized fillet tissues from rainbow trout (Oncorhynchus mykiss), walleye (Stizostedion vitreum), and channel catfish (Ictalurus punctatus) were fortified at nominal p-TSA concentrations of 17, 67, 200, 333, and 1000 ng/g. Samples were analyzed by isocratic reversed-phase liquid chromatography (LC) with absorbance detection at 226 nm. Mean recoveries of p-TSA ranged from 77 to 93.17%; relative standard deviations ranged from 1.5 to 14%; method quantitation limits ranged from 13 to 18 ng/g; and method detection limits ranged from 3.8 to 5.2 ng/g. The LC parameters produced p-TSA peaks without coelution of endogenous compounds and excluded chromatographic interference from at least 20 chemicals and drugs of potential use in aquaculture.

  7. Anthropogenic disturbance can determine the magnitude of opportunistic species responses on marine urban infrastructures.

    Science.gov (United States)

    Airoldi, Laura; Bulleri, Fabio

    2011-01-01

    Coastal landscapes are being transformed as a consequence of the increasing demand for infrastructures to sustain residential, commercial and tourist activities. Thus, intertidal and shallow marine habitats are largely being replaced by a variety of artificial substrata (e.g. breakwaters, seawalls, jetties). Understanding the ecological functioning of these artificial habitats is key to planning their design and management, in order to minimise their impacts and to improve their potential to contribute to marine biodiversity and ecosystem functioning. Nonetheless, little effort has been made to assess the role of human disturbances in shaping the structure of assemblages on marine artificial infrastructures. We tested the hypothesis that some negative impacts associated with the expansion of opportunistic and invasive species on urban infrastructures can be related to the severe human disturbances that are typical of these environments, such as those from maintenance and renovation works. Maintenance caused a marked decrease in the cover of dominant space occupiers, such as mussels and oysters, and a significant enhancement of opportunistic and invasive forms, such as biofilm and macroalgae. These effects were particularly pronounced on sheltered substrata compared to exposed substrata. Experimental application of the disturbance in winter reduced the magnitude of the impacts compared to application in spring or summer. We use these results to identify possible management strategies to inform the improvement of the ecological value of artificial marine infrastructures. We demonstrate that some of the impacts of globally expanding marine urban infrastructures, such as those related to the spread of opportunistic, and invasive species could be mitigated through ecologically-driven planning and management of long-term maintenance of these structures. Impact mitigation is a possible outcome of policies that consider the ecological features of built infrastructures and

  8. Anthropogenic disturbance can determine the magnitude of opportunistic species responses on marine urban infrastructures.

    Directory of Open Access Journals (Sweden)

    Laura Airoldi

    Full Text Available BACKGROUND: Coastal landscapes are being transformed as a consequence of the increasing demand for infrastructures to sustain residential, commercial and tourist activities. Thus, intertidal and shallow marine habitats are largely being replaced by a variety of artificial substrata (e.g. breakwaters, seawalls, jetties. Understanding the ecological functioning of these artificial habitats is key to planning their design and management, in order to minimise their impacts and to improve their potential to contribute to marine biodiversity and ecosystem functioning. Nonetheless, little effort has been made to assess the role of human disturbances in shaping the structure of assemblages on marine artificial infrastructures. We tested the hypothesis that some negative impacts associated with the expansion of opportunistic and invasive species on urban infrastructures can be related to the severe human disturbances that are typical of these environments, such as those from maintenance and renovation works. METHODOLOGY/PRINCIPAL FINDINGS: Maintenance caused a marked decrease in the cover of dominant space occupiers, such as mussels and oysters, and a significant enhancement of opportunistic and invasive forms, such as biofilm and macroalgae. These effects were particularly pronounced on sheltered substrata compared to exposed substrata. Experimental application of the disturbance in winter reduced the magnitude of the impacts compared to application in spring or summer. We use these results to identify possible management strategies to inform the improvement of the ecological value of artificial marine infrastructures. CONCLUSIONS/SIGNIFICANCE: We demonstrate that some of the impacts of globally expanding marine urban infrastructures, such as those related to the spread of opportunistic, and invasive species could be mitigated through ecologically-driven planning and management of long-term maintenance of these structures. Impact mitigation is a

  9. [Spectroscopic methods applied to component determination and species identification for coffee].

    Science.gov (United States)

    Chen, Hua-zhou; Xu, Li-li; Qin, Qiang

    2014-06-01

    Spectroscopic analysis was applied to the determination of the nutrient quality of ground, instant and chicory coffees. By using inductively coupled plasma atomic emission spectrometry (ICP-ES), nine mineral elements were determined in solid coffee samples. Caffeine was determined by ultraviolet (UV) spectrometry and organic matter was investigated by Fourier transform infrared (FTIR) spectroscopy. Oxidation-reduction titration was utilized for measuring the oxalate. The differences between ground coffee and instant coffee was identified on the basis of the contents of caffeine, oxalate and mineral elements. Experimental evidence showed that, caffeine in instant coffee was 2-3 times higher than in ground coffee. Oxalate in instant coffee was significantly higher in ground coffee. Mineral elements of Mg, P and Zn in ground coffee is lower than in instant coffee, while Cu is several times higher. The mineral content in chicory coffee is overall lower than the instant coffee. In addition, we determined the content of Ti for different types of coffees, and simultaneously detected the elements of Cu, Ti and Zn in chicory coffee. As a fast detection technique, FTIR spectroscopy has the potential of detecting the differences between ground coffee and instant coffee, and is able to verify the presence of caffeine and oxalate.

  10. Determination of concentration and molar absorptivity of hypochlorous acid and hypobromous acid species by hydrogen peroxide titration

    Science.gov (United States)

    Uehara, H.; Arakaki, T.

    2017-12-01

    Hypochlorous acid and hypobromous acid (abbreviated as "HypoX acids") are the main ingredients of bleaching and bactericides. The HypoX acids change their chemical forms depending on environmental factors such as pH and various chemical reactions. For example, it has been reported that hypobromite ion in water changes to carcinogenic bromate by photochemical reaction with ultraviolet light. In this study, concentrations of HypoX acids were determined by UV-VIS absorbance measurement utilizing the fact that HypoX acids react with hydrogen peroxide and do not co-exist in the solution. The method for determining the concentration by titration with hydrogen peroxide can be carried out simpler and more efficiently than the DPD method or the current titration method generally used for chlorine concentration measurement. Molar absorptivity between 250 - 500 nm of HypoX acids, including their conjugate base species, was determined by solving theoretical acid-base formula including molar fraction of each chemical species at various pHs. Molar absorptivity of OCl- and OBr- between 250 - 500 nm was determined based on the concentrations obtained from titration with hydrogen peroxide and absorbance at pH > 10, where OCl- and OBr- dominate. Furthermore, the HypoX acids solutions were irradiated with a solar simulator, and the photolysis rate constants were obtained. Based on those values, the half-lives were calculated and the behavior of HypoX acids in the environment was elucidated.

  11. Geomorphic determinants of species composition of alpine tundra, Glacier National Park, U.S.A.

    Science.gov (United States)

    George P. Malanson,; Bengtson, Lindsey E.; Fagre, Daniel B.

    2012-01-01

    Because the distribution of alpine tundra is associated with spatially limited cold climates, global warming may threaten its local extent or existence. This notion has been challenged, however, based on observations of the diversity of alpine tundra in small areas primarily due to topographic variation. The importance of diversity in temperature or moisture conditions caused by topographic variation is an open question, and we extend this to geomorphology more generally. The extent to which geomorphic variation per se, based on relatively easily assessed indicators, can account for the variation in alpine tundra community composition is analyzed versus the inclusion of broad indicators of regional climate variation. Visual assessments of topography are quantified and reduced using principal components analysis (PCA). Observations of species cover are reduced using detrended correspondence analysis (DCA). A “best subsets” regression approach using the Akaike Information Criterion for selection of variables is compared to a simple stepwise regression with DCA scores as the dependent variable and scores on significant PCA axes plus more direct measures of topography as independent variables. Models with geographic coordinates (representing regional climate gradients) excluded explain almost as much variation in community composition as models with them included, although they are important contributors to the latter. The geomorphic variables in the model are those associated with local moisture differences such as snowbeds. The potential local variability of alpine tundra can be a buffer against climate change, but change in precipitation may be as important as change in temperature.

  12. TLC determination of some flavanones in the buds of different genus Populus species and hybrids

    Directory of Open Access Journals (Sweden)

    Pobłocka-Olech Loretta

    2018-06-01

    Full Text Available Flavonoids in the buds of eight Populus species and hybrids were detected and compared with the aid of an optimized TLC method. Separation of 17 flavonoid aglycones belonging to different groups, namely, flavones, flavonols, flavanones and flavanonols, previously described as constituents of poplar buds, was performed on silica gel plates using a hexane/ethyl acetate/formic acid (60:40:1.3, V/V/V mixture as the mobile phase. Pinocembrin and pinostrobin were found in the majority of analyzed poplar buds. For quantitative analysis of both compounds, two TLC evaluation modes, densitometric and videodensitometric, were compared and the established methods were validated. Concentrations of flavanones in some extracts differed slightly or significantly due to the analyzed plant matrix complexity and the TLC evaluation mode applied. Poplar buds rich in flavanones originated from P. × canadensis ‘Robusta’ (1.82 and 2.23 g per 100 g, resp. and P. balsamifera (1.17 and 2.24 g per 100 g, resp..

  13. Determination of the radioiodine species in the exhaust air of nuclear facilities

    International Nuclear Information System (INIS)

    Birke, G.; Deuber, H.

    1977-01-01

    In the stack exhaust air of the nuclear power stations the portion of inorganic 131 I was, apart from 2 sampling periods, less than 50%. In the stack exhaust air of the research reactor the inorganic 131 I prevailed. The removal efficiency of the I 2 sorption materials DSM 11 and DSM 17 for 131 I in the form of CH 3 I and C 6 H 5 I was very low. 131 I in the form of C 6 H 5 I was removed by AC 6120 and LMS 13 X-Ag (Linde molecular sieve in the Ag form) to a very small extent too, by activated charcoal impregnated with KI or TEDA however to a very high extent. In the experiments concerning the preparation and removal of 131 I in the form of HIO an iodine species that was difficult to remove with AC 6120 was found which could be HIO. Its maximum portion in the carrier gas was 50%. (orig./RW) [de

  14. Cloud point extraction and spectrophotometric determination of mercury species at trace levels in environmental samples.

    Science.gov (United States)

    Ulusoy, Halil İbrahim; Gürkan, Ramazan; Ulusoy, Songül

    2012-01-15

    A new micelle-mediated separation and preconcentration method was developed for ultra-trace quantities of mercury ions prior to spectrophotometric determination. The method is based on cloud point extraction (CPE) of Hg(II) ions with polyethylene glycol tert-octylphenyl ether (Triton X-114) in the presence of chelating agents such as 1-(2-pyridylazo)-2-naphthol (PAN) and 4-(2-thiazolylazo) resorcinol (TAR). Hg(II) ions react with both PAN and TAR in a surfactant solution yielding a hydrophobic complex at pH 9.0 and 8.0, respectively. The phase separation was accomplished by centrifugation for 5 min at 3500 rpm. The calibration graphs obtained from Hg(II)-PAN and Hg(II)-TAR complexes were linear in the concentration ranges of 10-1000 μg L(-1) and 50-2500 μg L(-1) with detection limits of 1.65 and 14.5 μg L(-1), respectively. The relative standard deviations (RSDs) were 1.85% and 2.35% in determinations of 25 and 250 μg L(-1) Hg(II), respectively. The interference effect of several ions were studied and seen commonly present ions in water samples had no significantly effect on determination of Hg(II). The developed methods were successfully applied to determine mercury concentrations in environmental water samples. The accuracy and validity of the proposed methods were tested by means of five replicate analyses of the certified standard materials such as QC Metal LL3 (VWR, drinking water) and IAEA W-4 (NIST, simulated fresh water). Copyright © 2011 Elsevier B.V. All rights reserved.

  15. The Qualitative And Quantitative Determination Of The Phenolic Compounds In Polygonum Convolvulus L. Species, Polygonaceae Family

    Directory of Open Access Journals (Sweden)

    Olaru O T

    2013-06-01

    Full Text Available Introduction: Polygonum convolvulus L. (black bindweed, syn. Fallopia convolvulus (L. Á. Löve, Polygonaceae family is a plant from the spontaneous flora, spread from the plain zone up to the subalpine zone. The objectives of our researches are the qualitative and quantitative determination of polyphenolic compounds from Polygoni convolvuli herba and the choice of the adequate solvent for obtaining an active pharmacological extract.

  16. Is bark pH more important than tree species in determining the composition of nitrophytic or acidophytic lichen floras?

    Energy Technology Data Exchange (ETDEWEB)

    Spier, L. [Alterra, Landscape Center, POB 47, 6700 AA Wageningen (Netherlands); Dobben, H. van, E-mail: han.vandobben@wur.n [Alterra, Landscape Center, POB 47, 6700 AA Wageningen (Netherlands); Dort, K. van [Alterra, Landscape Center, POB 47, 6700 AA Wageningen (Netherlands)

    2010-12-15

    To study the pH preference of epiphytic lichens, the bark pH of Fraxinus, Tilia, Quercus and Ulmus trees in an urban environment was measured using a flat surface electrode. The total number of trees was 253. A survey was made of the lichens in a 40 x 40 cm quadrat surrounding the pH measurement point. Our data analysis using multivariate and univariate statistical techniques indicates that the tree species is the most important factor influencing lichen colonisation, and that bark pH alone is of less importance. We hypothesize that the changed pollution climate, with strong decreases in both sulphur dioxide and ammonia concentrations over the past two decades and a concomitant general increase in bark pH, has made epiphytes less sensitive to pH. - Tree species, rather than bark pH determines the occurrence of acidophytes and nitrophytes on trees.

  17. Determination of selected elements in red, brown and green seaweed species for monitoring pollution in the coastal environment of Ghana

    International Nuclear Information System (INIS)

    Serfor-Armah, Y.; Ghana Atomic Energy Commission, Legon-Accra; Ghana University, Legon-Accra; Carboo, D.; Akuamoah, R.K.; Chatt, A.

    2006-01-01

    The concentrations of 23 elements, namely Al, As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hf, Hg, I, K, La, Mg, Mn, Na, Ni, Sc, Sm, V, and Zn, in seven Rhodophyta (red), three Phaeophyta (brown) and five Chlorophyta (green) seaweed species from different areas along the coast of Ghana were determined using instrumental neutron activation analysis (INAA). These species can be potentially used as biomonitors. The INAA method involved irradiations using thermal and epithermal neutrons at the Dalhousie University SLOWPOKE-2 Reactor (DUSR) facility followed by conventional and anti-coincidence γ-ray spectrometry. The precision in terms of relative standard deviation was within ±4%. The accuracy of the methods was evaluated by analyzing four reference materials. Our results were within ±3% of the certified or information values in all cases. (author)

  18. Determination of total Betta-activity and heavy metals in biomonitor species (phytomonitors) from the area of ITR-Sofia

    International Nuclear Information System (INIS)

    Dimitrov, S.; Yovchev, M.; Geleva, E.

    2010-01-01

    For the purposes of environmental assessment of the area around the Research reactor in Sofia, species from monitored control points, selected in a certain way (habitat, population, air and hydrogeological parameters) are examined. Samples from following phytomonitored species: Betula pendula (silver birch) popullus canadensis (Canadian populus), Quercus sp. (Oak), Dactilus glomerata (Cock's-foot), Abies alba (Silver Fir) and Sequoia sempervirens (Coast Redwood) were analyzed. The total beta activity was determined by radiometric analysis and heavy metals content was measured using X-ray fluorescence analysis. The results are discussed in terms of radiation monitoring program of INRNE (gamma-background, aerosols, surface and groundwater, soil, plants) and obtained values are compared with reference points in the country

  19. Determination of Antioxidant, Anticholinesterase, Tyrosinase Inhibitory Activities and Fatty Acid Profiles of 10 Anatolian Klasea Cass. Species

    Directory of Open Access Journals (Sweden)

    Gülsen Tel

    2016-01-01

    Full Text Available In search of new natural fatty acid sources, extract of 10 different Turkish Klasea species were studies. Fatty acids of Klasea species were studied by GC and GC-MSD. Oleic acid (4.8-45.8%, palmitic acid (15.6-51.8%, linoleic acid (0.3-45.5%, palmitoleic acid (0.8-28.4% and linolenic acid (15.6-34.6% were the main fatty acids elucidated. All extracts were also subjected to acetylcholinesterase, butyrylcholinesterase, tyrosinase, β-carotene-linoleic acid, DPPH • scavenging, CUPRAC and ferrous ion-chelating ability activities. Total flavonoid and phenolic contents were determined as quercetin and pyrocatechol equivalents. All extracts showed significant antioxidant activity in all tests, except hexane extracts of K. serratuloides and K. cerinthifolia that showed weak inhibition against BChE and AChE. The hexane extract of K. coriaceae and methanol extract of K. serratuloides exhibited notable tyrosinase inhibitory activity.

  20. Applications of Qualitative Microanalysis to the Determination of Secondary Species Associated with Uranium; Application de la microanalyse qualitative a la determination des especes secondaires d'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Agrinier, H

    1959-02-01

    Microanalytical techniques are described which allow rapid determinations of secondary species associated with uranium. They consist in exposing the constituent elements of the ores by means of characteristic microchemical reactions. Because of their rapidity and the small amount of apparatus needed, these techniques can be used either in the field or in the laboratory. (author) [French] Les techniques de microanalyse decrites dans cet ouvrage permettent la determination rapide des especes secondaires d'uranium. Elles consistent a mettre en evidence les elements constitutifs des mineraux par des reactions microchimiques caracteristiques. En raison de leur rapidite et du peu de materiel qu'elles necessitent, ces techniques peuvent etre utilisees aussi bien sur le terrain qu'au laboratoire. (auteur)

  1. Improvement on simultaneous determination of chromium species in aqueous solution by ion chromatography and chemiluminescence detection

    DEFF Research Database (Denmark)

    Gammelgaard, Bente; Liao, Y.P.; Jons, O.

    1997-01-01

    A sensitive method for the simultaneous determination of chromium(III) and chromium(VI) was chromatography and chemiluminescence detection. Two Dionex ion-exchange guard columns in series, CG5 and AG7, were used to separate chromium(III) from chromium(VI). Chromium(VI) was reduced by potassium......, the stabilities of reductant and luminol solutions were studied. The linear range of the calibration curve for chromium(III) and chromium(VI) was 1-400 mu g l(-1). The detection limit was 0.12 mu g l(-1) for chromium(III) and 0.09 mu g l(-1) for chromium(VI), respectively. The precision at the 20 mu g l(-1) level...... was 1.4% for chromium(III) and 2.5% for chromium(VI), respectively. The accuracy of the chromium(III) determination was determined by analysis of the NIST standard reference material 1643c, Trace elements in water with the result 19.1 +/- 1.0 mu g Cr(III) l(-1) (certified value 19.0 +/- 0.6 mu g Cr...

  2. Determination of reactive oxygen species from ZnO micro-nano structures with shape-dependent photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    He, Weiwei; Zhao, Hongxiao; Jia, Huimin [Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University, Henan 461000 (China); Yin, Jun-Jie [Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD 20740 (United States); Zheng, Zhi, E-mail: zhengzhi99999@gmail.com [Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University, Henan 461000 (China)

    2014-05-01

    Graphical abstract: ZnO micro/nano structures with shape dependent photocatalytic activity were prepared by hydrothermal reaction. The generations of hydroxyl radical, superoxide and singlet oxygen from irradiated ZnO were identified precisely by electron spin resonance spectroscopy. The type of reactive oxygen species was determined by band gap structure of ZnO. - Highlights: • ZnO micro/nano structures with different morphologies were prepared by solvothermal reaction. • Multi-pod like ZnO structures exhibited superior photocatalytic activity. • The generations of hydroxyl radical, superoxide and singlet oxygen from irradiated ZnO were characterized precisely by electron spin resonance spectroscopy. • The type of reactive oxygen species was determined by band gap structure of ZnO. - Abstract: ZnO micro/nano structures with different morphologies have been prepared by the changing solvents used during their synthesis by solvothermal reaction. Three typical shapes of ZnO structures including hexagonal, bell bottom like and multi-pod formed and were characterized by scanning electron microscopy and X-ray diffraction. Multi pod like ZnO structures exhibited the highest photocatalytic activity toward degradation of methyl orange. Using electron spin resonance spectroscopy coupled with spin trapping techniques, we demonstrate an effective way to identify precisely the generation of hydroxyl radicals, superoxide and singlet oxygen from the irradiated ZnO multi pod structures. The type of reactive oxygen species formed was predictable from the band gap structure of ZnO. These results indicate that the shape of micro-nano structures significantly affects the photocatalytic activity of ZnO, and demonstrate the value of electron spin resonance spectroscopy for characterizing the type of reactive oxygen species formed during photoexcitation of semiconductors.

  3. Determination of reactive oxygen species from ZnO micro-nano structures with shape-dependent photocatalytic activity

    International Nuclear Information System (INIS)

    He, Weiwei; Zhao, Hongxiao; Jia, Huimin; Yin, Jun-Jie; Zheng, Zhi

    2014-01-01

    Graphical abstract: ZnO micro/nano structures with shape dependent photocatalytic activity were prepared by hydrothermal reaction. The generations of hydroxyl radical, superoxide and singlet oxygen from irradiated ZnO were identified precisely by electron spin resonance spectroscopy. The type of reactive oxygen species was determined by band gap structure of ZnO. - Highlights: • ZnO micro/nano structures with different morphologies were prepared by solvothermal reaction. • Multi-pod like ZnO structures exhibited superior photocatalytic activity. • The generations of hydroxyl radical, superoxide and singlet oxygen from irradiated ZnO were characterized precisely by electron spin resonance spectroscopy. • The type of reactive oxygen species was determined by band gap structure of ZnO. - Abstract: ZnO micro/nano structures with different morphologies have been prepared by the changing solvents used during their synthesis by solvothermal reaction. Three typical shapes of ZnO structures including hexagonal, bell bottom like and multi-pod formed and were characterized by scanning electron microscopy and X-ray diffraction. Multi pod like ZnO structures exhibited the highest photocatalytic activity toward degradation of methyl orange. Using electron spin resonance spectroscopy coupled with spin trapping techniques, we demonstrate an effective way to identify precisely the generation of hydroxyl radicals, superoxide and singlet oxygen from the irradiated ZnO multi pod structures. The type of reactive oxygen species formed was predictable from the band gap structure of ZnO. These results indicate that the shape of micro-nano structures significantly affects the photocatalytic activity of ZnO, and demonstrate the value of electron spin resonance spectroscopy for characterizing the type of reactive oxygen species formed during photoexcitation of semiconductors

  4. Adult Pacific Lamprey Migration Behavior and Escapement in the Bonneville Reservoir and Lower Columbia River Monitored Using the Juvenile Salmonid Acoustic Telemetry System (JSATS), 2011

    Science.gov (United States)

    2012-01-01

    sea lions (Zalophus californicus, Eumetopias jubatus) or white sturgeon (Acipenser transmontanus) in the tailrace, moved to spawning tributaries...and management of three parasitic lampreys of North America. Fisheries 35:580-594. Close, D. A., M. Fitzpatrick, and H. Li. 2002. The ecological

  5. Flow regime in a restored wetland determines trophic links and species composition in the aquatic macroinvertebrate community

    Energy Technology Data Exchange (ETDEWEB)

    González-Ortegón, E., E-mail: quique.gonzalezortegon@andaluciajunta.es [School of Ocean Sciences, Bangor University, Menai Bridge LL59 5AB (United Kingdom); IFAPA Centro El Toruño, Camino Tiro de Pichón s/n, 11500 El Puerto de Santa María (Spain); Walton, M.E.M.; Moghaddam, B. [School of Ocean Sciences, Bangor University, Menai Bridge LL59 5AB (United Kingdom); Vilas, C.; Prieto, A. [IFAPA Centro El Toruño, Camino Tiro de Pichón s/n, 11500 El Puerto de Santa María (Spain); Kennedy, H.A. [School of Ocean Sciences, Bangor University, Menai Bridge LL59 5AB (United Kingdom); Pedro Cañavate, J. [IFAPA Centro El Toruño, Camino Tiro de Pichón s/n, 11500 El Puerto de Santa María (Spain); Le Vay, L. [School of Ocean Sciences, Bangor University, Menai Bridge LL59 5AB (United Kingdom)

    2015-01-15

    In a restored wetland (South of Spain), where different flow regimes control water exchange with the adjacent Guadalquivir estuary, the native Palaemon varians coexists with an exotic counterpart species Palaemon macrodactylus. This controlled m/acrocosm offers an excellent opportunity to investigate how the effects of water management, through different flow regimes, and the presence of a non-native species affect the aquatic community and the trophic niche (by gut contents and C-N isotopic composition) of the native shrimp Palaemon varians. We found that increased water exchange rate (5% day{sup −1} in mixed ponds vs. 0.1% day{sup −1} in extensive ponds) modified the aquatic community of this wetland; while extensive ponds are dominated by isopods and amphipods with low presence of P. macrodactylus, mixed ponds presented high biomass of mysids, corixids, copepods and both shrimp species. An estuarine origin of nutrients and primary production might explain seasonal and spatial differences found among ponds of this wetland. A combined analysis of gut contents and isotopic composition of the native and the exotic species showed that: (1) native P. varians is mainly omnivorous (2) while the non-native P. macrodactylus is more zooplanktivorous and (3) a dietary overlap occurred when both species coexist at mixed ponds where a higher water exchange and high abundance of mysids and copepods diversifies the native species' diet. Thus differences in the trophic ecology of both species are clearly explained by water management. This experimental study is a valuable tool for integrated management between river basin and wetlands since it allows quantification of wetland community changes in response to the flow regime. - Highlights: • Flow regimen is a major determinant of physicochemical habitat of a wetland. • Water exchanges wetland-estuary modify its aquatic community and trophic links. • Omnivory and physiological tolerance key in the resistance of a

  6. Flow regime in a restored wetland determines trophic links and species composition in the aquatic macroinvertebrate community

    International Nuclear Information System (INIS)

    González-Ortegón, E.; Walton, M.E.M.; Moghaddam, B.; Vilas, C.; Prieto, A.; Kennedy, H.A.; Pedro Cañavate, J.; Le Vay, L.

    2015-01-01

    In a restored wetland (South of Spain), where different flow regimes control water exchange with the adjacent Guadalquivir estuary, the native Palaemon varians coexists with an exotic counterpart species Palaemon macrodactylus. This controlled m/acrocosm offers an excellent opportunity to investigate how the effects of water management, through different flow regimes, and the presence of a non-native species affect the aquatic community and the trophic niche (by gut contents and C-N isotopic composition) of the native shrimp Palaemon varians. We found that increased water exchange rate (5% day −1 in mixed ponds vs. 0.1% day −1 in extensive ponds) modified the aquatic community of this wetland; while extensive ponds are dominated by isopods and amphipods with low presence of P. macrodactylus, mixed ponds presented high biomass of mysids, corixids, copepods and both shrimp species. An estuarine origin of nutrients and primary production might explain seasonal and spatial differences found among ponds of this wetland. A combined analysis of gut contents and isotopic composition of the native and the exotic species showed that: (1) native P. varians is mainly omnivorous (2) while the non-native P. macrodactylus is more zooplanktivorous and (3) a dietary overlap occurred when both species coexist at mixed ponds where a higher water exchange and high abundance of mysids and copepods diversifies the native species' diet. Thus differences in the trophic ecology of both species are clearly explained by water management. This experimental study is a valuable tool for integrated management between river basin and wetlands since it allows quantification of wetland community changes in response to the flow regime. - Highlights: • Flow regimen is a major determinant of physicochemical habitat of a wetland. • Water exchanges wetland-estuary modify its aquatic community and trophic links. • Omnivory and physiological tolerance key in the resistance of a wetland

  7. Rapid determination of selenium in various marine species by instrumental neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Landsberger, S; Hoffman, E [McMaster Univ., Hamilton, Ontario (Canada). McMaster Nuclear Reactor

    1984-08-16

    INAA was used to determine selenium concentrations in several marine organisms including two certified reference materials (NRCC lobster hepatopancreas, NBC oyster tissue) and one uncertified material (IAEA fish homogenate). The /sup 76/Se(n,..gamma..) sup(77m)Se (T=17.4 s) reaction was successfully employed to achieve an overall precision between 3-10% and detection limits between 0.3-0.6 ..mu..g/g. The accuracy of the results, as compared to the certified values, was in excellent agreement with the NBS material and only slightly lower (approx. 9%) for the NRCC material.

  8. Observing the Behavior of Larval Sea Lamprey in the St Clair River

    Science.gov (United States)

    Howard, M.

    2016-12-01

    The objective of this study was to use student-built underwater water quality monitoring systems to monitor the behavior of larval sea lamprey during a lampricide treatment in the St Clair River, MI. In addition, the monitoring systems were used to gather video evidence to show that lampricide does not affect the surrounding wildlife. This camera system was an addition to the Great Lakes Fisheries Commission's (GLFC) study because they previously did not have video recording capabilities. To collect the needed video data, we lined eight cameras down each side of a 25 by 20 meter lampricide plot in the middle channel of the St Clair River, which was approximately 1 to 5 meters deep. This setup allowed us to collect 8 hours worth of video after a 24 hour delay, which was then saved as a MP4 format for easy access by the GLFC scientists. After retrieving the systems from the study plot, we had found mussels growing on the monitoring systems' housings. When analyzing the cameras' data, we also saw regular wildlife activity, such as groups of fish swimming normally past the cameras. We know that the wildlife's behavior was not affected, because in the videos that were captured during the application of this lampricide treatment showed no abnormal wildlife behavior. Through this study, we learned that the Bayluscide 70% wettable powder did not affect fish, aquatic plants, or any other sea life in the treatment area. Our water quality monitoring systems were an impact in the GLFC's lampricide study, because they provided evidence that lampricide does not affect any other wildlife in the treatment area.

  9. Speciative determination of total V and dissolved inorganic vanadium species in environmental waters by catalytic–kinetic spectrophotometric method

    Directory of Open Access Journals (Sweden)

    Ramazan Gürkan

    2017-02-01

    Full Text Available A kinetic determination of V(V as a catalyst was spectrophotometrically performed by using the indicator reaction of Gallamine blue (GB+ and bromate at pH 2.0. The reaction was followed by measuring absorbance change for a fixed-time of 3 min at 537 nm. The variables such as reagent concentration, pH, buffer concentration, ionic strength and temperature were optimized to improve the selectivity and sensitivity. Under the optimized conditions, the determination of V(V was performed in the range 1–100 μg L−1 with limits of detection and quantification of 0.31 and 0.94 μg L−1. The developed kinetic method is sufficiently sensitive, selective and simple. It was successfully applied to the speciative determination of total V and inorganic dissolved vanadium species, V(V and V(IV in environmental water samples. The oxidizing property of permanganate is used to differentiate between V(IV and V(V species. The V(IV content was found by subtracting the V(V content from those of total V. The recovery is above 95% for V(V spiked samples. Additionally, the accuracy was validated by analysis of a certified water sample, CRM TMDA-53.3, and the results were in good agreement with the certified value.

  10. Determination of arsenic species in rice samples using CPE and ETAAS.

    Science.gov (United States)

    Costa, Bruno Elias Dos Santos; Coelho, Nívia Maria Melo; Coelho, Luciana Melo

    2015-07-01

    A highly sensitive and selective procedure for the determination of arsenate and total arsenic in food by electrothermal atomic absorption spectrometry after cloud point extraction (ETAAS/CPE) was developed. The procedure is based on the formation of a complex of As(V) ions with molybdate in the presence of 50.0 mmol L(-1) sulfuric acid. The complex was extracted into the surfactant-rich phase of 0.06% (w/v) Triton X-114. The variables affecting the complex formation, extraction and phase separation were optimized using factorial designs. Under the optimal conditions, the calibration graph was linear in the range of 0.05-10.0 μg L(-1). The detection and quantification limits were 10 and 33 ng L(-1), respectively and the corresponding value for the relative standard deviation for 10 replicates was below 5%. Recovery values of between 90.8% and 113.1% were obtained for spiked samples. The accuracy of the method was evaluated by comparison with the results obtained for the analysis of a rice flour sample (certified material IRMM-804) and no significant difference at the 95% confidence level was observed. The method was successfully applied to the determination of As(V) and total arsenic in rice samples. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. On problem of ultrasensitive determination of man-made plutonium in living species

    CERN Document Server

    Perelygin, V P; Dmitriev, S N; Oganessian, Yu T; Petrova, R I; Drobina, T P

    1999-01-01

    To improve the sensitivity of the method of Pu determination in specimens we applied two additional steps of chemical separation of Pu from U. After the usual chemical separation of Pu we used second step with ion-exchange column, where the ions of U sup 4 sup + were absorbed by sorbent and Pu sup 3 sup + ions remains in solution. For converting Plutonium to Pu sup 3 sup + state the electrochemical procedure has been used. After the electrochemical separation procedure the solution was deposited onto quartz glass. Then the quartz glass plates were inserted into the gas mixture flow (SOCL sub 2 +air) at the temperature 650 deg. C. Such a procedure extracts >=90% U from Pu layer. Now we provide the chemical separation of Pu from U by a factor >=10 sup 7. It means that now we are able to perform the routine Pu analysis at the level of sensitivity 10 sup - sup 1 sup 4 -10 sup - sup 1 sup 5 g/g. By using combined n-gamma activation technique we can determine the Pu content in the small fragments of tissues of livi...

  12. Origin Determination and Differentiation of Gelatin Species of Bovine, Porcine, and Piscine through Analytical Methods

    Directory of Open Access Journals (Sweden)

    Hatice Saadiye Eryılmaz

    2017-06-01

    Full Text Available Gelatin origin determination has been a crucial issue with respect to religion and health concerns. It is necessary to analyze the origin of gelatin with reliable methods to ensure not only consumer choices but also safety and legal requirements such as labeling. There are many analytical methods developed for detection and/or quantification of gelatin from different sources including bovine, porcine and piscine. These analytical methods can be divided into physicochemical, chromatographic, immunochemical, spectroscopic and molecular methods. Moreover, computational methods have been used in some cases consecutively to ensure sensitivity of the analytical methods. Every method has different advantages and limitations due to their own principles, applied food matrix and process conditions of material. The present review intends to give insight into novel analytical methods and perspectives that have been developed to differentiate porcine, bovine and piscine gelatins and to establish their authenticity. Almost every method can be succeeded in origin determination; however, it is a matter of sensitivity in that some researches fail to ensure sufficient differentiation.

  13. Traits determining the digestibility-decomposability relationships in species from Mediterranean rangelands.

    Science.gov (United States)

    Bumb, Iris; Garnier, Eric; Coq, Sylvain; Nahmani, Johanne; Del Rey Granado, Maria; Gimenez, Olivier; Kazakou, Elena

    2018-03-05

    Forage quality for herbivores and litter quality for decomposers are two key plant properties affecting ecosystem carbon and nutrient cycling. Although there is a positive relationship between palatability and decomposition, very few studies have focused on larger vertebrate herbivores while considering links between the digestibility of living leaves and stems and the decomposability of litter and associated traits. The hypothesis tested is that some defences of living organs would reduce their digestibility and, as a consequence, their litter decomposability, through 'afterlife' effects. Additionally in high-fertility conditions the presence of intense herbivory would select for communities dominated by fast-growing plants, which are able to compensate for tissue loss by herbivory, producing both highly digestible organs and easily decomposable litter. Relationships between dry matter digestibility and decomposability were quantified in 16 dominant species from Mediterranean rangelands, which are subject to management regimes that differ in grazing intensity and fertilization. The digestibility and decomposability of leaves and stems were estimated at peak standing biomass, in plots that were either fertilized and intensively grazed or unfertilized and moderately grazed. Several traits were measured on living and senesced organs: fibre content, dry matter content and nitrogen, phosphorus and tannin concentrations. Digestibility was positively related to decomposability, both properties being influenced in the same direction by management regime, organ and growth forms. Digestibility of leaves and stems was negatively related to their fibre concentrations, and positively related to their nitrogen concentration. Decomposability was more strongly related to traits measured on living organs than on litter. Digestibility and decomposition were governed by similar structural traits, in particular fibre concentration, affecting both herbivores and micro

  14. Determination of the sources of the airborne physico-chemical 131I species in a PWR power plant

    International Nuclear Information System (INIS)

    Deuber, H.; Wilhelm, J.G.

    1978-01-01

    In a 1300 MWE PWR power plant the sources of the airborne 131 I species were determined over a period of 5 months. During power operation the main source of the radiologically decisive elemental 131 I was the exhaust from the hoods in which samples from the primary coolant are taken and processed. During refueling outage elemental 131 I was mainly contributed by the containment purge air. By efficient filtration of these exhausts, a reduction of the ingestion dose, caused by the total 131 I stack release, by a factor of nearly 4 during power operation and of possibly 10 during refueling outage can be accomplished. (author)

  15. Determination of phytoextraction potential of plant species for toxic elements in soils of abandoned sulphide-mining areas

    International Nuclear Information System (INIS)

    Freitas, M.C.; Anawar, H.M.; Dionisio, I.; Dung, H.M.; Canha, N.; Bettencourt, A.; Capelo, S.; Henriques, F.; Pinto-Gomes, C.J.

    2009-01-01

    This study has determined contamination levels in soils and plants from the Sao Domingos mining area, Portugal, by k 0 -INAA. Total concentrations of As, Sb, Cr, Hg, Cu, Zn and Fe in soils were very high, exceeding the maximum limits in Portuguese legislation. Concentrations of toxic elements like As, Sb and Zn were highest in roots of Erica andevalensis, Juncus acutus, Agrostis castellana and Nicotiana glauca. Additionally, As, Br, Cr, Fe, Sb and Zn in all organs of most plants were above toxicity levels. Those species that accumulated relatively high concentrations of toxic elements in roots (and tops) may be cultivated for phytostabilisation of similar areas. (author)

  16. Patterns of invasion and colonization of the sea lamprey (Petromyzon marinus) in North America as revealed by microsatellite genotypes.

    Science.gov (United States)

    Bryan, M B; Zalinski, D; Filcek, K B; Libants, S; Li, W; Scribner, K T

    2005-10-01

    Invasions by exotic organisms have had devastating affects on aquatic ecosystems, both ecologically and economically. One striking example of a successful invader that has dramatically affected fish community structure in freshwater lakes of North America is the sea lamprey (Petromyzon marinus). We used eight microsatellite loci and multiple analytical techniques to examine competing hypotheses concerning the origins and colonization history of sea lamprey (n = 741). Analyses were based on replicated invasive populations from Lakes Erie, Huron, Michigan, and Superior, populations of unknown origins from Lakes Ontario, Champlain, and Cayuga, and populations of anadromous putative progenitor populations in North America and Europe. Populations in recently colonized lakes were each established by few colonists through a series of genetic bottlenecks which resulted in lower allelic diversity in more recently established populations. The spatial genetic structure of invasive populations differed from that of native populations on the Atlantic coast, reflecting founder events and connectivity of invaded habitats. Anadromous populations were found to be panmictic (theta(P) = 0.002; 95% CI = -0.003-0.006; P > 0.05). In contrast, there was significant genetic differentiation between populations in the lower and upper Great Lakes (theta(P) = 0.007; P freshwater habitats were examined using coalescent-based analyses, and demonstrated that populations likely originated from natural migrations via the St Lawrence River.

  17. Pre-spawning migration of adult Pacific lamprey, Entosphenus tridentatus, in the Willamette River, Oregon, U.S.A.

    Science.gov (United States)

    Clemens, Benjamin J.; Mesa, Matthew G.; Magie, Robert J.; Young, Douglas A.; Schreck, Carl B.

    2012-01-01

    We describe the migration distances and timing of the adult Pacific lamprey, Entosphenus tridentatus, in the Willamette River Basin (Oregon, U.S.A.). We conducted aerial surveys to track radio-tagged fish upstream of a major waterfall and hydropower complex en route to spawning areas. We detected 24 out of the 43 fish that passed the waterfall-hydropower complex. Of the detected fish, 17 were detected multiple times. Their maximum migration distance upstream in the mainstem Willamette approximated a normal distribution. The maximum distance migrated upstream did not significantly correlate with total body length (r = −0.186, P = 0.385) or date that the fish passed Willamette Falls (r = −0.118, P = 0.582). Fish migrated primarily during the spring to early summer period before stopping during the summer, when peak river temperatures (≥20°C). However, at least three fish continued to migrate upstream after September. Behavior ranged from relatively slow migration, followed by holding; to rapid migration, followed by slow migration further up in the basin. This study provides a basis for informing more detailed research on Pacific lamprey in the future.

  18. Preliminary study of the influence of red blood cells morphometry on the species determinism of domestic animals

    Directory of Open Access Journals (Sweden)

    Nezar Adili

    2014-04-01

    Full Text Available Aim: This survey was realized on cattle, sheep, goats, horses, and dogs, in order to study the influence of three morphometric parameters: the diameter, the circumference and the surface of red blood cells on the determinism of these species. Materials and Methods: For each species, blood samples were taken from 15 adult female by jugular venipuncture with confection of blood smears on microscope slides immediately after blood collection and stained according to the method of May-Gründwald Giemsa. Morphometric study was realized using the software OPTIKA Pro Vision. To better describe the results, the statistical analysis was assessed by using the descriptive Boxplots test, ANOVA, and the Student's t-test. Results: The morphometric parameters of red blood cells are biggest in dogs followed by horses, cattle, and sheep, while goats have the lowest ones. Conclusion: This investigation allowed us to show that from a drop of blood we can have an idea about the animal species taking into account the diameter, the circumference, and the surface of erythrocytes.

  19. Determining Human Clot Lysis Time (in vitro with Plasminogen/Plasmin from Four Species (Human, Bovine, Goat, and Swine

    Directory of Open Access Journals (Sweden)

    Omaira Cañas Bermúdez

    2015-05-01

    Full Text Available Cardiovascular disease is the leading cause of death worldwide, including failures in the plasminogen/plasmin system which is an important factor in poor lysis of blood clots. This article studies the fibrinolytic system in four species of mammals, and it identifies human plasminogen with highest thrombolysis efficiency. It examines plasminogen from four species (human, bovine, goat, and swine and identifies the most efficient one in human clot lysis in vitro. All plasminogens were identically purified by affinity chromatography. Human fibrinogen was purified by fractionation with ethanol. The purification of both plasminogen and fibrinogen was characterized by one-dimensional SDS-PAGE (10%. Human clot formation in vitro and its dissolution by plasminogen/plasmin consisted of determining lysis time from clot formation to its dilution. Purification of proteins showed greater than 95% purity, human plasminogen showed greater ability to lyse clot than animal plasminogen. The article concludes that human plasminogen/plasmin has the greatest catalysis and efficiency, as it dissolves human clot up to three times faster than that of irrational species.

  20. Species-Level Differences in Hyperspectral Metrics among Tropical Rainforest Trees as Determined by a Tree-Based Classifier

    Directory of Open Access Journals (Sweden)

    Dar A. Roberts

    2012-06-01

    Full Text Available This study explores a method to classify seven tropical rainforest tree species from full-range (400–2,500 nm hyperspectral data acquired at tissue (leaf and bark, pixel and crown scales using laboratory and airborne sensors. Metrics that respond to vegetation chemistry and structure were derived using narrowband indices, derivative- and absorption-based techniques, and spectral mixture analysis. We then used the Random Forests tree-based classifier to discriminate species with minimally-correlated, importance-ranked metrics. At all scales, best overall accuracies were achieved with metrics derived from all four techniques and that targeted chemical and structural properties across the visible to shortwave infrared spectrum (400–2500 nm. For tissue spectra, overall accuracies were 86.8% for leaves, 74.2% for bark, and 84.9% for leaves plus bark. Variation in tissue metrics was best explained by an axis of red absorption related to photosynthetic leaves and an axis distinguishing bark water and other chemical absorption features. Overall accuracies for individual tree crowns were 71.5% for pixel spectra, 70.6% crown-mean spectra, and 87.4% for a pixel-majority technique. At pixel and crown scales, tree structure and phenology at the time of image acquisition were important factors that determined species spectral separability.

  1. Cloning, phylogeny, and regional expression of a Y5 receptor mRNA in the brain of the sea lamprey (Petromyzon marinus).

    Science.gov (United States)

    Pérez-Fernández, Juan; Megías, Manuel; Pombal, Manuel A

    2014-04-01

    The NPY receptors known as Y receptors are classified into three subfamilies, Y1, Y2, and Y5, and are involved in different physiological functions. The Y5 receptor is the only member of the Y5 subfamily, and it is present in all vertebrate groups, except for teleosts. Both molecular and pharmacological studies show that Y5 receptor is highly conserved during vertebrate evolution. Furthermore, this receptor is widely expressed in the mammalian brain, including the hypothalamus, where it is thought to take part in feeding and homeostasis regulation. Lampreys belong to the agnathan lineage, and they are thought to have branched out between the two whole-genome duplications that occurred in vertebrates. Therefore, they are in a key position for studies on the evolution of gene families in vertebrates. Here we report the cloning, phylogeny, and brain expression pattern of the sea lamprey Y5 receptor. In phylogenetic studies, the lamprey Y5 receptor clusters in a basal position, together with Y5 receptors of other vertebrates. The mRNA of this receptor is broadly expressed in the lamprey brain, being especially abundant in hypothalamic areas. Its expression pattern is roughly similar to that reported for other vertebrates and parallels the expression pattern of the Y1 receptor subtype previously described by our group, as it occurs in mammals. Altogether, these results confirm that a Y5 receptor is present in lampreys, thus being highly conserved during the evolution of vertebrates, and suggest that it is involved in many brain functions, the only known exception being teleosts. Copyright © 2013 Wiley Periodicals, Inc.

  2. Electrochemical Study of Carbon Nanotubes/Nanohybrids for Determination of Metal Species Cu2+ and Pb2+ in Water Samples

    Directory of Open Access Journals (Sweden)

    Andréa Claudia Oliveira Silva

    2016-01-01

    Full Text Available The use of nanomaterials, such as nanoparticles and nanotubes, for electrochemical detection of metal species has been investigated as a way of modifying electrodes by electrochemical stripping analysis. The present study develops a new methodology based on a comparative study of nanoparticles and nanotubes with differential pulse anodic stripping voltammetry (DPASV and examines the simultaneous determination of copper and lead. The glassy carbon electrode modified by gold nanoparticles demonstrated increased sensitivity and decreased detection limits, among other improvements in analytical performance data. Under optimized conditions (deposition potential −0.8 V versus Ag/AgCl; deposition time, 300 s; resting time, 10 s; pulse amplitude, 50 mV; and voltage step height, 4 mV, the detection limits were 0.2279 and 0.3321 ppb, respectively, for determination of Pb2+ and Cu2+. The effects of cations and anions on the simultaneous determination of metal ions do not exhibit significant interference, thereby demonstrating the selectivity of the electrode for simultaneous determination of Pb2+ and Cu2+. The same method was also used to determine Cu2+ in water samples.

  3. Transcriptional profiling to address molecular determinants of endometrial receptivity--lessons from studies in livestock species.

    Science.gov (United States)

    Ulbrich, Susanne E; Groebner, Anna E; Bauersachs, Stefan

    2013-01-01

    The development of a fertilized oocyte into a differentiated multi-cellular organism is a major challenge with regard to the orchestration of the expression of the mammalian genome. Highly complex networks of genes are temporally and spatially regulated during cellular differentiation to generate specific cell types. Embryonic development is critically influenced by external impacts in the female reproductive tract. A most critical phase of pregnancy in mammals is the pre- and peri-implantation period, during which the uterine environment plays a crucial role in supporting the development of the conceptus. The analytical description of the transcriptome, proteome and metabolome of the embryo-maternal interface is a prerequisite for the understanding of the complex regulatory processes taking place during this time. This review lines out potentials and limitations of different approaches to unravel the determinants of endometrial receptivity in cattle, the pig and the horse. Suitable in vivo and in vitro models, which have been used to elucidate factors participating in the embryo-maternal dialog are discussed. Taken together, transcriptome analyses and specified selective candidate gene driven approaches contribute to the understanding of endometrial function. The endometrium as sensor and driver of fertility may indicate the qualitative and quantitative nature of signaling molecules sent by the early embryo and in turn, accordingly impact on embryonic development. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Direct molecular mass determination of trehalose monomycolate from 11 species of mycobacteria by MALDI-TOF mass spectrometry.

    Science.gov (United States)

    Fujita, Yukiko; Naka, Takashi; Doi, Takeshi; Yano, Ikuya

    2005-05-01

    Direct estimation of the molecular mass of single molecular species of trehalose 6-monomycolate (TMM), a ubiquitous cell-wall component of mycobacteria, was performed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. When less than 1 microg TMM was analysed by MALDI-TOF mass spectrometry, quasimolecular ions [M+Na]+ of each molecular species were demonstrated and the numbers of carbons and double bonds (or cyclopropane rings) were determined. Since the introduction of oxygen atoms such as carbonyl, methoxy and ester groups yielded the appropriate shift of mass ions, the major subclasses of mycolic acid (alpha, methoxy, keto and wax ester) were identified without resorting to hydrolytic procedures. The results showed a marked difference in the molecular species composition of TMM among mycobacterial species. Unexpectedly, differing from other mycoloyl glycolipids, TMM from Mycobacterium tuberculosis showed a distinctive mass pattern, with abundant odd-carbon-numbered monocyclopropanoic (or monoenoic) alpha-mycolates besides dicyclopropanoic mycolate, ranging from C75 to C85, odd- and even-carbon-numbered methoxymycolates ranging from C83 to C94 and even- and odd-carbon-numbered ketomycolates ranging from C83 to C90. In contrast, TMM from Mycobacterium bovis (wild strain and BCG substrains) possessed even-carbon-numbered dicyclopropanoic alpha-mycolates. BCG Connaught strain lacked methoxymycolates almost completely. These results were confirmed by MALDI-TOF mass analysis of mycolic acid methyl esters liberated by alkaline hydrolysis and methylation of the original TMM. Wax ester-mycoloyl TMM molecular species were demonstrated for the first time as an intact form in the Mycobacterium avium-intracellulare group, M. phlei and M. flavescens. The M. avium-intracellulare group possessed predominantly C85 and C87 wax ester-mycoloyl TMM, while M. phlei and the rapid growers tested contained C80, C81, C82 and C83 wax ester

  5. Using niche-modelling and species-specific cost analyses to determine a multispecies corridor in a fragmented landscape

    Science.gov (United States)

    Zurano, Juan Pablo; Selleski, Nicole; Schneider, Rosio G.

    2017-01-01

    Misiones, Argentina, contains the largest remaining tract of Upper Paraná Atlantic Forest ecoregion; however, ~50% of native forest is unprotected and located in a mosaic of plantations, agriculture, and pastures. Existing protected areas are becoming increasingly isolated due to ongoing habitat modification. These factors, combined with lower than expected regional carnivore densities, emphasize the need to understand the effect of fragmentation on animal movement and connectivity between protected areas. Using detection dogs and genetic analyses of scat, we collected data on jaguars (Panthera onca), pumas (Puma concolor), ocelots (Leopardus pardalis), oncillas (Leopardus tigrinus), and bush dogs (Speothos venaticus) across habitats that varied in vegetation, disturbance, human proximity, and protective status. With MaxEnt we evaluated habitat use, habitat suitability, and potential species richness for the five carnivores across northern-central Misiones, Argentina. Through a multifaceted cost analysis that included unique requirements of each carnivore and varying degrees of overlap among them, we determined the optimal location for primary/secondary corridors that would link the northern-central zones of the Green Corridor in Misiones and identified areas within these corridors needing priority management. A secondary analysis, comparing these multispecies corridors with the jaguar’s unique requirements, demonstrated that this multispecies approach balanced the preferences of all five species and effectively captured areas required by this highly restricted and endangered carnivore. We emphasize the potential importance of expanding beyond a single umbrella or focal species when developing biological corridors that aim to capture the varied ecological requirements of coexisting species and ecological processes across the landscape. Detection dogs and genetic analyses of scat allow data on multiple species to be collected efficiently across multiple habitat

  6. Frequency Determination of Ureaplasma and Mycoplasma Genitalium Species in Female with Vaginitis Infection using Real- Time PCR

    Directory of Open Access Journals (Sweden)

    Mina Zolfaghari

    2017-02-01

    Full Text Available Abstract Background: Ureaplasma and M. genitalium species belong to a kind of bacteria that are sexually transmitted and are the possible cause of pelvic inflammatory disease and nongonococcal urethritis, and et al. The aim of this study was to determine the urea plasma and Mycoplasma genitalium species frequency in women with vaginal infection and various sexual partners who referred to women, s health promotion and treatment center in Arak. Materials and Methods: Endocervical swab samples from 110 women with vaginal infections referred to women’s health promotion and treatment center in Arak, were prepared. Patients’ personal information and identities during reception process were registered. The samples were transferred to the laboratory in the transport environment and after DNA extraction, were evaluated according to Real-time PCR assay. Results: Urea plasma and Mycoplasma genitalium bacteria existed in 96(87.27% and 4(3.63% of patients, respectively. Among them, 4 cases had both bacteria infections. The amount of isolation in young women between 30-39 years old was more than others. Conclusion: The results show that the colonization of urea plasma species in adult women is 40-80% and in studied group is 87.27%. These results indicate that with due attention to the increasing number of sexual partners and the increase of sexual activity, the urea plasma colonization of women will increase. In view of the potential influence of mycoplasma species on side effects resulted from pregnancy infection of mothers and mortality, on-time diagnosis and treatment will be increasingly essential.

  7. Determination and application of immunodominant regions of SARS coronavirus spike and nucleocapsid proteins recognized by sera from different animal species.

    Science.gov (United States)

    Yu, Meng; Stevens, Vicky; Berry, Jody D; Crameri, Gary; McEachern, Jennifer; Tu, Changchun; Shi, Zhengli; Liang, Guodong; Weingartl, Hana; Cardosa, Jane; Eaton, Bryan T; Wang, Lin-Fa

    2008-02-29

    Knowledge of immunodominant regions in major viral antigens is important for rational design of effective vaccines and diagnostic tests. Although there have been many reports of such work done for SARS-CoV, these were mainly focused on the immune responses of humans and mice. In this study, we aim to search for and compare immunodominant regions of the spike (S) and nucleocapsid (N) proteins which are recognized by sera from different animal species, including mouse, rat, rabbit, civet, pig and horse. Twelve overlapping recombinant protein fragments were produced in Escherichia coli, six each for the S and N proteins, which covered the entire coding region of the two proteins. Using a membrane-strip based Western blot approach, the reactivity of each antigen fragment against a panel of animal sera was determined. Immunodominant regions containing linear epitopes, which reacted with sera from all the species tested, were identified for both proteins. The S3 fragment (aa 402-622) and the N4 fragment (aa 220-336) were the most immunodominant among the six S and N fragments, respectively. Antibodies raised against the S3 fragment were able to block the binding of a panel of S-specific monoclonal antibodies (mAb) to SARS-CoV in ELISA, further demonstrating the immunodominance of this region. Based on these findings, one-step competition ELISAs were established which were able to detect SARS-CoV antibodies from human and at least seven different animal species. Considering that a large number of animal species are known to be susceptible to SARS-CoV, these assays will be a useful tool to trace the origin and transmission of SARS-CoV and to minimise the risk of animal-to-human transmission.

  8. Determining the Diversity and Species Abundance Patterns in Arctic Soils using Rational Methods for Exploring Microbial Diversity

    Science.gov (United States)

    Ovreas, L.; Quince, C.; Sloan, W.; Lanzen, A.; Davenport, R.; Green, J.; Coulson, S.; Curtis, T.

    2012-12-01

    Arctic microbial soil communities are intrinsically interesting and poorly characterised. We have inferred the diversity and species abundance distribution of 6 Arctic soils: new and mature soil at the foot of a receding glacier, Arctic Semi Desert, the foot of bird cliffs and soil underlying Arctic Tundra Heath: all near Ny-Ålesund, Spitsbergen. Diversity, distribution and sample sizes were estimated using the rational method of Quince et al., (Isme Journal 2 2008:997-1006) to determine the most plausible underlying species abundance distribution. A log-normal species abundance curve was found to give a slightly better fit than an inverse Gaussian curve if, and only if, sequencing error was removed. The median estimates of diversity of operational taxonomic units (at the 3% level) were 3600-5600 (lognormal assumed) and 2825-4100 (inverse Gaussian assumed). The nature and origins of species abundance distributions are poorly understood but may yet be grasped by observing and analysing such distributions in the microbial world. The sample size required to observe the distribution (by sequencing 90% of the taxa) varied between ~ 106 and ~105 for the lognormal and inverse Gaussian respectively. We infer that between 5 and 50 GB of sequencing would be required to capture 90% or the metagenome. Though a principle components analysis clearly divided the sites into three groups there was a high (20-45%) degree of overlap in between locations irrespective of geographical proximity. Interestingly, the nearest relatives of the most abundant taxa at a number of most sites were of alpine or polar origin. Samples plotted on first two principal components together with arbitrary discriminatory OTUs

  9. Determination of minimum inhibitory concentrations of itraconazole, terbinafine and ketoconazole against dermatophyte species by broth microdilution method.

    Science.gov (United States)

    Bhatia, V K; Sharma, P C

    2015-01-01

    Various antifungal agents both topical and systemic have been introduced into clinical practice for effectively treating dermatophytic conditions. Dermatophytosis is the infection of keratinised tissues caused by fungal species of genera Trichophyton, Epidermophyton and Microsporum, commonly known as dermatophytes affecting 20-25% of the world's population. The present study aims at determining the susceptibility patterns of dermatophyte species recovered from superficial mycoses of human patients in Himachal Pradesh to antifungal agents; itraconazole, terbinafine and ketoconazole. The study also aims at determining the minimum inhibitory concentrations (MICs) of these agents following the recommended protocol of Clinical and Laboratory Standards Institute (CLSI) (M38-A2). A total of 53 isolates of dermatophytes (T. mentagrophyte-34 in no., T. rubrum-18 and M. gypseum-1) recovered from the superficial mycoses were examined. Broth microdilution method M38-A2 approved protocol of CLSI (2008) for filamentous fungi was followed for determining the susceptibility of dermatophyte species. T. mentagrophyte isolates were found more susceptible to both itraconazole and ketoconazole as compared to terbinafine (MIC50: 0.125 µg/ml for itraconazole, 0.0625 µg/ml for ketoconazole and 0.5 µg/ml for terbinafine). Three isolates of T. mentagrophytes (VBS-5, VBSo-3 and VBSo-73) and one isolate of T. rubrum (VBPo-9) had higher MIC values of itraconazole (1 µg/ml). Similarly, the higher MIC values of ketoconazole were observed in case of only three isolates of T. mentagrophyte (VBSo-30 = 2 µg/ml; VBSo-44, VBM-2 = 1 µg/ml). The comparative analysis of the three antifungal drugs based on t-test revealed that 'itraconazole and terbinafine' and 'terbinafine and ketoconazole' were found independent based on the P terbinafine and ketoconazole'. The MIC values observed in the present study based on standard protocol M38-A2 of CLSI 2008 might serve as reference for further studies

  10. Determination of minimum inhibitory concentrations of itraconazole, terbinafine and ketoconazole against dermatophyte species by broth microdilution method

    Directory of Open Access Journals (Sweden)

    V K Bhatia

    2015-01-01

    Full Text Available Purpose: Various antifungal agents both topical and systemic have been introduced into clinical practice for effectively treating dermatophytic conditions. Dermatophytosis is the infection of keratinised tissues caused by fungal species of genera Trichophyton, Epidermophyton and Microsporum, commonly known as dermatophytes affecting 20–25% of the world's population. The present study aims at determining the susceptibility patterns of dermatophyte species recovered from superficial mycoses of human patients in Himachal Pradesh to antifungal agents; itraconazole, terbinafine and ketoconazole. The study also aims at determining the minimum inhibitory concentrations (MICs of these agents following the recommended protocol of Clinical and Laboratory Standards Institute (CLSI (M38-A2. Methodology: A total of 53 isolates of dermatophytes (T. mentagrophyte-34 in no., T. rubrum-18 and M. gypseum-1 recovered from the superficial mycoses were examined. Broth microdilution method M38-A2 approved protocol of CLSI (2008 for filamentous fungi was followed for determining the susceptibility of dermatophyte species. Results: T. mentagrophyte isolates were found more susceptible to both itraconazole and ketoconazole as compared to terbinafine (MIC50: 0.125 µg/ml for itraconazole, 0.0625 µg/ml for ketoconazole and 0.5 µg/ml for terbinafine. Three isolates of T. mentagrophytes (VBS-5, VBSo-3 and VBSo-73 and one isolate of T. rubrum (VBPo-9 had higher MIC values of itraconazole (1 µg/ml. Similarly, the higher MIC values of ketoconazole were observed in case of only three isolates of T. mentagrophyte (VBSo-30 = 2 µg/ml; VBSo-44, VBM-2 = 1 µg/ml. The comparative analysis of the three antifungal drugs based on t-test revealed that 'itraconazole and terbinafine' and 'terbinafine and ketoconazole' were found independent based on the P < 0.005 in case of T. mentagrophyte isolates. In case of T. rubrum, the similarity existed between MIC values of 'itraconazole and

  11. A new, rapid and reliable method for the determination of reduced sulphur (S2-) species in natural water discharges

    International Nuclear Information System (INIS)

    Montegrossi, Giordano; Tassi, Franco; Vaselli, Orlando; Bidini, Eva; Minissale, Angelo

    2006-01-01

    The determination of reduced S species in natural waters is particularly difficult due to their high instability and chemical and physical interferences in the current analytical methods. In this paper a new, rapid and reliable analytical procedure is presented, named the Cd-IC method, for their determination as ΣS 2- via oxidation to SO 4 2- after chemical trapping with an ammonia-cadmium solution that allows precipitation of all the reduced S species as CdS. The S 2- -SO 4 is analysed by ion-chromatography. The main advantages of this method are: low cost, high stability of CdS precipitate, absence of interferences, low detection limit (0.01mg/L as SO 4 for 10mL of water) and low analytical error (about 5%). The proposed method has been applied to more than 100 water samples from different natural systems (water discharges and cold wells from volcanic and geothermal areas, crater lakes) in central-southern Italy

  12. Spectroscopic determination of species and divergence of hydrogen beams in the W7AS neutral beam injectors

    International Nuclear Information System (INIS)

    Ott, W.; Penningsfeld, F.P.

    1993-01-01

    Light-collecting systems are installed at the neutralizers of the W7AS neutral beam lines. They receive light emitted at an angle of 120 to the beam axes. Hydrogen beams are analyzed at around the wavelength of H α (6562.8 A), helium beams at around 5875.6 A. The hydrogen spectra show the well-known shifted and unshifted lines emitted by the different beam species and the background gas. The line widths are mainly determined by the beam focussing, the beamlet divergence and the apparatus profile. Knowing the focussing properties of the ion source and the instrument function of the spectrometer, one can determine the beamlet divergence. The spectrum is approximated by a series of Gaussians using least-squares fitting methods and evaluated with respect to beam species and divergence. Evaluation of the spectra proved difficult because they show a structured background, which is observed in the whole range of the Doppler shift. It is shown with helium beams that the background is caused by wall reflection of light emitted by the beam in the whole angular range between 0 and 180 . The knowledge of the background structure gained with He beams allows interpretation of the more complicated hydrogen spectra. (orig.)

  13. [Determination of iodine and its species in plant samples using ion chromatography-inductively coupled plasma mass spectrometry].

    Science.gov (United States)

    Lin, Li; Chen, Guang; Chen, Yuhong

    2011-07-01

    A method was established for the determination of iodine and its species in plant samples using ion chromatography-inductively coupled plasma mass spectrometry (IC-ICP/ MS). Alkaline extraction and IC-ICP/MS were applied as the sample pre-treatment method and the detection technique respectively, for iodate and iodide determination. Moreover, high-temperature pyrolysis absorption was adopted as the pre-treatment method for total iodine analysis, which finally converted all the iodine species into iodide and measured the iodide by IC-ICP/MS. The recoveries of iodine for alkaline extraction and high-temperature pyrolysis absorption were 89.6%-97.5% and 95.2%-111.2%, respectively. The results were satisfactory. The detection limit of iodine was 0.010 mg/kg. The iodine and its speciation contents in several kinds of plant samples such as seaweeds, kelp, cabbage, tea leaf and spinach were investigated. It was shown that the iodine in seaweeds mainly existed as organic iodine; while the ones in kelp, cabbage, tea leaf and spinach mainly existed as inorganic iodine.

  14. Determination of inorganic arsenic species in natural waters--benefits of separation and preconcentration on ion exchange and hybrid resins.

    Science.gov (United States)

    Ben Issa, Nureddin; Rajaković-Ognjanović, Vladana N; Jovanović, Branislava M; Rajaković, Ljubinka V

    2010-07-19

    A simple method for the separation and determination of inorganic arsenic (iAs) species in natural and drinking water was developed. Procedures for sample preparation, separation of As(III) and As(V) species and preconcentration of the total iAs on fixed bed columns were defined. Two resins, a strong base anion exchange (SBAE) resin and a hybrid (HY) resin were utilized. The inductively-coupled plasma-mass spectrometry method was applied as the analytical method for the determination of the arsenic concentration in water. The governing factors for the ion exchange/sorption of arsenic on resins in a batch and a fixed bed flow system were analyzed and compared. Acidity of the water, which plays an important role in the control of the ionic or molecular forms of arsenic species, was beneficial for the separation; by adjusting the pH values to less than 8.00, the SBAE resin separated As(V) from As(III) in water by retaining As(V) and allowing As(III) to pass through. The sorption activity of the hydrated iron oxide particles integrated into the HY resin was beneficial for bonding of all iAs species over a wide range of pH values from 5.00 to 11.00. The resin capacities were calculated according to the breakthrough points in a fixed bed flow system. At pH 7.50, the SBAE resin bound more than 370 microg g(-1) of As(V) while the HY resin bound more than 4150 microg g(-1) of As(III) and more than 3500 microg g(-1) of As(V). The high capacities and selectivity of the resins were considered as advantageous for the development and application of two procedures, one for the separation and determination of As(III) (with SBAE) and the other for the preconcentration and determination of the total arsenic (with HY resin). Methods were established through basic analytical procedures (with external standards, certified reference materials and the standard addition method) and by the parallel analysis of some samples using the atomic absorption spectrometry-hydride generation

  15. Assessment of the risk of drowning at low-head dams used as sea lamprey barriers in Ontario[Includes the CSCE forum on professional practice and career development : 1. international engineering mechanics and materials specialty conference : 1. international/3. coastal, estuarine and offshore engineering specialty conference : 2. international/8. construction specialty conference

    Energy Technology Data Exchange (ETDEWEB)

    Mazurek, K.A.; Thomson, J.; Amos, M. [Saskatchewan Univ., Saskatoon, SK (Canada). Dept. of Civil and Geological Engineering; Hallett, A. [A. Hallett, Sault Ste. Marie, ON (Canada); Aktar, A. [Indian Inst. of Technology, Kanpur (India). Dept. of Civil Engineering; Katopodis, C. [Fisheries and Oceans Canada, Winnipeg, MB (Canada). Freshwater Inst.

    2009-07-01

    In 2003, there were 54 fixed-crest lamprey barriers used in the Great Lakes region, with more construction planned. Although the barriers are relatively small structures of about 1-2 m in height, they present a drowning hazard. On the downstream side of the structure, a submerged hydraulic jump creates a strong vortex flow that even an experienced swimmer cannot escape. This study developed a method to assess the risk of hazardous flows at the barrier sites to enable dam owners to decide whether or not mitigative measures need to be undertaken at their sites. This hazard assessment was demonstrated for 2 existing lamprey barriers in Ontario, namely the Duffins Creek Barrier at Ajax and the Little Otter Creek Barrier near Straffordville. However, the work can be applied to the dam safety assessment and the development of potential mitigative strategies for drowning at other low-head dams and weirs. A flow-duration curves was developed for each site in order to determine the risk of having a drowning hazard at the barrier sites. In the flow-duration analysis, the percentage time, or probability, that a given flow rate was equalled or exceeded was calculated directly from observations of the average daily discharge in the channel. 18 refs., 1 tab., 7 figs.

  16. β-arrestin functionally regulates the non-bleaching pigment parapinopsin in lamprey pineal.

    Directory of Open Access Journals (Sweden)

    Emi Kawano-Yamashita

    2011-01-01

    Full Text Available The light response of vertebrate visual cells is achieved by light-sensing proteins such as opsin-based pigments as well as signal transduction proteins, including visual arrestin. Previous studies have indicated that the pineal pigment parapinopsin has evolutionally and physiologically important characteristics. Parapinopsin is phylogenetically related to vertebrate visual pigments. However, unlike the photoproduct of the visual pigment rhodopsin, which is unstable, dissociating from its chromophore and bleaching, the parapinopsin photoproduct is stable and does not release its chromophore. Here, we investigated arrestin, which regulates parapinopsin signaling, in the lamprey pineal organ, where parapinopsin and rhodopsin are localized to distinct photoreceptor cells. We found that beta-arrestin, which binds to stimulated G protein-coupled receptors (GPCRs other than opsin-based pigments, was localized to parapinopsin-containing cells. This result stands in contrast to the localization of visual arrestin in rhodopsin-containing cells. Beta-arrestin bound to cultured cell membranes containing parapinopsin light-dependently and translocated to the outer segments of pineal parapinopsin-containing cells, suggesting that beta-arrestin binds to parapinopsin to arrest parapinopsin signaling. Interestingly, beta-arrestin colocalized with parapinopsin in the granules of the parapinopsin-expressing cell bodies under light illumination. Because beta-arrestin, which is a mediator of clathrin-mediated GPCR internalization, also served as a mediator of parapinopsin internalization in cultured cells, these results suggest that the granules were generated light-dependently by beta-arrestin-mediated internalization of parapinopsins from the outer segments. Therefore, our findings imply that beta-arrestin-mediated internalization is responsible for eliminating the stable photoproduct and restoring cell conditions to the original dark state. Taken together with a

  17. Identification of Nematode Fauna in Vineyards of South of Western Azerbaijan and Determination of the Dominant Parasitic Species

    Directory of Open Access Journals (Sweden)

    E. Mohajeri

    2017-12-01

    samples were collected from the rhizosphere of grapevines from the depth between 10 and 80 cm from the soil surface after digging and separating the surface dry soil. About 2 kg soil from each vineyard from several places were collected and by means of a plastic bag was transferred to the laboratory where they were kept in the refrigerator at 4-degree centigrade until used. Nematodes were extracted from the soil by combined sieving and centrifugal-flotation method and processed to be transferred to glycerin. After preparing microscopic slides, the morphological and morphometrical features of the nematodes were studied using the light microscope equipped with a drawing tube. Identification of the genera and species was performed using reliable sources and valid nematode identification keys and the morphological features. The measurements of the extracted nematodes were compared with those ones given in literature and their similarities and differences with original descriptions and closest species were discussed. Results and Discussion: As a result, 23 species belonging to 15 genera including Amplimerliniusglobigerus, Basiriatumida, Boleodorusthylactus, Discotylenchusdiscretus, Ditylenchusacutus, Ditylenchusmyceliophagus, Filenchus vulgaris, Geocenamusbrevidens, Geocenamusrugosus, Helicotylenchuspseudorobustus, Helicotylenchus vulgaris, Mesocriconemaantipolitanum, Mesocriconemaxenoplax, Paratylenchuslabiosus, Pratylenchoidesvariabilis, Pratylenchuscoffeae, Pratylenchusneglectus, Pratylenchuspenetrans, Pratylenchussefaensis, Praylenchusscribneri, Scutylenchuspaniculoides, Xiphinema index andZygotylenchusguevaraiwere identified. Five isolated species namely, Helicotylenchus vulgaris,Mesocriconemaantipolitanum, Mesocriconemaxenoplax, Helicotylenchuspseudorobustusand Pratylenchusneglectus respectively based on the frequency and distribution in the soil samples are determined as dominant parasite species. Here, the two more dominant species, Helicotylenchus vulgaris and

  18. Inorganic species of arsenic in soil solution determined by microcartridges and ferrihydrite-based diffusive gradient in thin films (DGT).

    Science.gov (United States)

    Moreno-Jiménez, Eduardo; Six, Laetitia; Williams, Paul N; Smolders, Erik

    2013-01-30

    The bioavailability of soil arsenic (As) is determined by its speciation in soil solution, i.e., arsenite [As(III)] or arsenate [As(V)]. Soil bioavailability studies require suitable methods to cope with small volumes of soil solution that can be speciated directly after sampling, and thereby minimise any As speciation change during sample collection. In this study, we tested a self-made microcartridge to separate both As species and compared it to a commercially available cartridge. In addition, the diffusive gradient in thin films technique (DGT), in combination with the microcartridges, was applied to synthetic solutions and to a soil spiked with As. This combination was used to improve the assessment of available inorganic As species with ferrihydrite(FH)-DGT, in order to validate the technique for environmental analysis, mainly in soils. The self-made microcartridge was effective in separating As(III) from As(V) in solution with detection by inductively coupled plasma optical emission spectrometry (ICP-OES) in volumes of only 3 ml. The DGT study also showed that the FH-based binding gels are effective for As(III) and As(V) assessment, in solutions with As and P concentrations and ionic strength commonly found in soils. The FH-DGT was tested on flooded and unflooded As spiked soils and recoveries of As(III) and As(V) were 85-104% of the total dissolved As. This study shows that the DGT with FH-based binding gel is robust for assessing inorganic species of As in soils. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Comparative Study of Different Methods to Determine the Role of Reactive Oxygen Species Induced by Zinc Oxide Nanoparticles

    Directory of Open Access Journals (Sweden)

    Nigar A. Najim

    2016-08-01

    Full Text Available Accumulation of reactive oxygen species (ROS followed by an increase in oxidative stress is associated with cellular responses to nanoparticle induced cell damages. Finding the best method for assessing intracellular ROS production is the key step in the detection of oxidative stress induced injury. This study evaluates and compares four different methods for the measurement of intracellular ROS generation using fluorogenic probe, 2´,7´-dichlorofluorescein diacetate (DCFH-DA. Hydrogen peroxide (H2O2 was utilised as a positive control to assess the reactivity of the probe. Spherically shaped zinc oxide (ZnO nanoparticles with an average particle size of 85.7 nm were used to determine the diverse roles of ROS in nanotoxicity in Hs888Lu and U937 cell lines. The results showed that different methods exhibit different patterns of ROS measurement. In conclusion this study found that the time point at which the DCFH-DA is added to the reaction, the incubation time and the oxidative species that is responsible for the oxidation of DCFH, have impact on the intracellular ROS measurement.

  20. Determination of thephysico-chemical 131I species in the exhausts and stack effluent of a PWR power plant

    International Nuclear Information System (INIS)

    Deuber, H.; Wilhelm, J.G.

    1979-01-01

    To quantify the credit that can be granted in the assessment of the 131 I ingestion doses and the improvement that can be achieved in the ventilation systems if differences of the physico-chemical 131 I species with respect to the environmental impact are taken into account, the fractions of the 131 I species were determined in the stack effluent and in various exhausts of a 1300 MW/sub e/ PWR power plant during a period of 3 months. Based on these measurements, calculations for different cases of filtration of the main exhausts for iodine were carried out. The average fractions of elemental and organic 131 I were about 70 and 30% respectively in the stack effluent during the time indicated. Elem. 131 I orginated mainly from the hoods in which samples of the primary coolant are taken and processed. Org. 131 I was mainly contributed by the equipment compartments. If the hood exhaust had been filtered, as was the case with the equipment compartment exhaust, the fractions of elem. and org. 131 I would have been on the order of 50% each and the calculated 131 I ingestion doses would have been a factor of 3 lower

  1. An analytical procedure for determination of sulphur species and isotopes in boreal acid sulphate soils and sediments

    Directory of Open Access Journals (Sweden)

    K. BACKLUND

    2008-12-01

    Full Text Available An analytical scheme suitable for boreal acid sulphate (AS soils and sediments was developed on the basis of existing methods. The presented procedure can be used to quantify and discriminate among acid volatile sulphide, cold chromium reducible sulphur, hot chromium reducible sulphur, elemental sulphur, sulphate sulphur, organic sulphur, total reducible sulphur and total sulphur. The sulphur fractions are recovered as either Ag2S or BaSO4 precipitates and can further be used for isotope analysis. Overlaps between sulphur species are common during speciation, and must be minimized. Some of these overlaps are caused by poor sampling and storage, inappropriate conditions during the distillation, or natural variations in the sample (e.g. Fe3+ interference and grain size. The procedural impact was determined by conducting tests on both artificial and natural samples containing one or several sulphur species. The method is applied on reduced sediment from an AS soil locality (Överpurmo and a brackish lake (Larsmo Lake in western Finland and the results, including S-isotopes, are discussed.;

  2. [Determination of tick species and treatment of cows, sheep and goats in the Sivas-Zara region].

    Science.gov (United States)

    Mamak, Nuri; Gençer, Lütfiye; Ozkanlar, Yunus Emre; Ozçelik, Semra

    2006-01-01

    The purpose of this study was to examine tick infestation in cattle, sheep and goats in the Zara-Sivas region for one year and to determine the epizootiology of the tick species as well as to investigate treatment of the infested animals. Tick infestation was detected in 71 (29.6%) out of 240 cattle, 66 (24.0%) out of 275 sheep and 50 (19.9%) out of 252 goats in the Zara region. It has been shown that the tick infestation on cattle included Haemaphysalis parva (33.8%), Dermacentor marginatus (2.8%), Boophilus annulatus (21.1%), Haemaphysalis concinna (15.5%), Hyalomma marginatum (19.7%) and Rhipicephalus bursa (7%). Those on sheep included Dermacentor niveus (18.2%), Dermacentor marginatus (31.8%), Haemaphysalis parva (13.6%), Haemaphysalis concinna (4.5%), Hyalomma marginatum (4.5%) and Rhipicephalus bursa (27.3%). Those on goats included Dermacentor niveus (4%), Dermacentor marginatus (12%), Haemaphysalis parva (40%), Haemaphysalis concinna (2%), Boophilus annulatum (4%), Hyalomma marginatum (6%) and Rhipicephalus bursa (32%). Ivermectin was administered to the infested animals in a dose of 200 microg/kg subcutaneously. The administration of the ivermectin was effective. As a result, it has been shown that the tick infestation is present in cattle, sheep and goats in Zara region, the tick species differ according to the season and administration of ivermectin was an effective treatment.

  3. Probing the electronic structure of redox species and direct determination of intrinsic reorganization energies of electron transfer reactions

    International Nuclear Information System (INIS)

    Wang, Xue-Bin; Wang, Lai-Sheng

    2000-01-01

    An experimental technique capable of directly determining the intrinsic reorganization energies of bimolecular electron transfer reactions is described. Appropriate solution phase redox species are prepared in the gas phase using electrospray ionization and probed using photodetachment spectroscopy. Five metal complex anions involved in the Fe 2+ -Fe 3+ redox couple are investigated and the intramolecular reorganization energies are measured directly from spectral features due to removing the most loosely bound 3d electron from the Fe(II)-complexes. The photodetachment spectra also yield electronic structure information about the Fe 2+ -Fe 3+ redox couple and provide a common electronic structure origin for the reducing capability of the Fe(II)-complexes, the most common redox reagents. (c) 2000 American Institute of Physics

  4. Evaluation of solid-phase microextraction conditions for the determination of polycyclic aromatic hydrocarbons in aquatic species using gas chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Aguinaga, N.; Campillo, N.; Vinas, P.; Hernandez-Cordoba, M. [University of Murcia, Department of Analytical Chemistry, Faculty of Chemistry, Murcia (Spain)

    2008-06-15

    This paper describes a headspace solid-phase microextraction (HS-SPME) procedure coupled to gas chromatography with mass spectrometric detection (GC-MS) for the determination of eight PAHs in aquatic species. The influence of various parameters on the PAH extraction efficiency was carefully examined. At 75 C and for an extraction time of 60 min, a polydimethylsiloxane-divinylbenzene (PDMS/DVB) fiber coating was found to be most suitable. Under the optimized conditions, detection limits ranged from 8 to 450 pg g{sup -1}, depending on the compound and the sample matrix. The repeatability varied between 7 and 15% (RSD). Accuracy was tested using the NIST SRM 1974b reference material. The method was successfully applied to different samples, and the studied PAHs were detected in several of the samples. (orig.)

  5. Ground-Based Remote Sensing and Imaging of Volcanic Gases and Quantitative Determination of Multi-Species Emission Fluxes

    Directory of Open Access Journals (Sweden)

    Ulrich Platt

    2018-01-01

    Full Text Available The physical and chemical structure and the spatial evolution of volcanic plumes are of great interest since they influence the Earth’s atmospheric composition and the climate. Equally important is the monitoring of the abundance and emission patterns of volcanic gases, which gives insight into processes in the Earth’s interior that are difficult to access otherwise. Here, we review spectroscopic approaches (from ultra-violet to thermal infra-red to determine multi-species emissions and to quantify gas fluxes. Particular attention is given to the emerging field of plume imaging and quantitative image interpretation. Here UV SO2 cameras paved the way but several other promising techniques are under study and development. We also give a brief summary of a series of initial applications of fast imaging techniques for volcanological research.

  6. Activities of Fluconazole, Caspofungin, Anidulafungin, and Amphotericin B on Planktonic and Biofilm Candida Species Determined by Microcalorimetry

    Science.gov (United States)

    Maiolo, Elena Maryka; Furustrand Tafin, Ulrika; Borens, Olivier

    2014-01-01

    We investigated the activities of fluconazole, caspofungin, anidulafungin, and amphotericin B against Candida species in planktonic form and biofilms using a highly sensitive assay measuring growth-related heat production (microcalorimetry). C. albicans, C. glabrata, C. krusei, and C. parapsilosis were tested, and MICs were determined by the broth microdilution method. The antifungal activities were determined by isothermal microcalorimetry at 37°C in RPMI 1640. For planktonic Candida, heat flow was measured in the presence of antifungal dilutions for 24 h. Candida biofilm was formed on porous glass beads for 24 h and exposed to serial dilutions of antifungals for 24 h, and heat flow was measured for 48 h. The minimum heat inhibitory concentration (MHIC) was defined as the lowest antifungal concentration reducing the heat flow peak by ≥50% (≥90% for amphotericin B) at 24 h for planktonic Candida and at 48 h for Candida biofilms (measured also at 24 h). Fluconazole (planktonic MHICs, 0.25 to >512 μg/ml) and amphotericin B (planktonic MHICs, 0.25 to 1 μg/ml) showed higher MHICs than anidulafungin (planktonic MHICs, 0.015 to 0.5 μg/ml) and caspofungin (planktonic MHICs, 0.125 to 0.5 μg/ml). Against Candida species in biofilms, fluconazole's activity was reduced by >1,000-fold compared to its activity against the planktonic counterparts, whereas echinocandins and amphotericin B mainly preserved their activities. Fluconazole induced growth of planktonic C. krusei at sub-MICs. At high concentrations of caspofungin (>4 μg/ml), paradoxical growth of planktonic C. albicans and C. glabrata was observed. Microcalorimetry enabled real-time evaluation of antifungal activities against planktonic and biofilm Candida organisms. It can be used in the future to evaluate new antifungals and antifungal combinations and to study resistant strains. PMID:24566186

  7. Molecular characteristics of extended-spectrum beta-lactamases and qnr determinants in Enterobacter species from Japan.

    Science.gov (United States)

    Kanamori, Hajime; Yano, Hisakazu; Hirakata, Yoichi; Hirotani, Ayako; Arai, Kazuaki; Endo, Shiro; Ichimura, Sadahiro; Ogawa, Miho; Shimojima, Masahiro; Aoyagi, Tetsuji; Hatta, Masumitsu; Yamada, Mitsuhiro; Gu, Yoshiaki; Tokuda, Koichi; Kunishima, Hiroyuki; Kitagawa, Miho; Kaku, Mitsuo

    2012-01-01

    The incidence of extended-spectrum β-lactamases (ESBLs) has been increasing worldwide, but screening criteria for detection of ESBLs are not standardized for AmpC-producing Enterobacteriaceae such as Enterobacter species. In this study, we investigated the prevalence of ESBLs and/or AmpC β-lactamases in Japanese clinical isolates of Enterobacter spp. and the association of plasmid-mediated quinolone resistance (PMQR) determinants with ESBL producers. A total of 364 clinical isolates of Enterobacter spp. collected throughout Japan between November 2009 and January 2010 were studied. ESBL-producing strains were assessed by the CLSI confirmatory test and the boronic acid disk test. PCR and sequencing were performed to detect CTX-M, TEM, and SHV type ESBLs and PMQR determinants. For ESBL-producing Enterobacter spp., pulsed-field gel electrophoresis (PFGE) was performed using XbaI restriction enzyme. Of the 364 isolates, 22 (6.0%) were ESBL producers. Seven isolates of Enterobacter cloacae produced CTX-M-3, followed by two isolates producing SHV-12. Two isolates of Enterobacter aerogenes produced CTX-M-2. Of the 22 ESBL producers, 21 had the AmpC enzyme, and six met the criteria for ESBL production in the boronic acid test. We found a significant association of qnrS with CTX-M-3-producing E. cloacae. The 11 ESBL-producing Enterobacter spp. possessing bla(CTX-M), bla(SHV), or bla(TEM) were divided into six unique PFGE types. This is the first report about the prevalence of qnr determinants among ESBL-producing Enterobacter spp. from Japan. Our results suggest that ESBL-producing Enterobacter spp. with qnr determinants are spreading in Japan.

  8. Studies on endangered and rare non-commercial fish species recorded in the Pomeranian Bay (southern Baltic Sea) in 2010-2013

    Science.gov (United States)

    Więcaszek, Beata; Sobecka, Ewa; Keszka, Sławomir; Stepanowska, Katarzyna; Dudko, Stanisław; Biernaczyk, Marcin; Wrzecionkowski, Konrad

    2015-12-01

    This paper presents the results of studies on endangered and rare non-commercial fish species ( Spinachia spinachia, Nerophis ophidion, Syngnathus typhle, Agonus cataphractus, Pholis gunnellus, Enchelyopus cimbrius, Cyclopterus lumpus) and one lamprey species ( Lampetra fluviatilis), recorded as bycatch during monitoring surveys in 2010-2013 in the Pomeranian Bay. Two species were observed for the first time in the Pomeranian Bay: A. cataphractus and E. cimbrius. Descriptions of parasite fauna are provided for C. lumpus and E. cimbrius, which were infected with four pathogenic species from Neomonada, Digenea, Nematoda, and Acanthocephala. Almost all parasite species were new in the hosts examined.

  9. Electrochemical generation of arsenic volatile species using a gold/mercury amalgam cathode. Determination of arsenic by atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Andrea Caiminagua

    2015-03-01

    Full Text Available The electrochemical generation of arsenic volatile species (arsine using an Au/Hg amalgam cathode in a 0.5 M H2SO4 solution, is described. Results were compared with those obtained with other cathodes commonly used for generation of arsine. The effects of the electrolytic conditions and interferent ions have been studied. Results show that the Au/Hg cathode has better tolerance to interference and higher repeatability than cathodes made out of platinum (Pt, gold (Au, reticulated glassy carbon (RGC, lead (Pb. Under optimized conditions, a 0.027 μg L−1 (3σ detection limit for As(III in aqueous solutions and a 2.4% relative standard deviation for a 0.1 μg L−1 As(III were obtained. The accuracy of the method was verified by determination of As in a certified reference material. The proposed method was applied to the determination of As in spiked tap water samples.

  10. Determination of DPPH Radical Oxidation Caused by Methanolic Extracts of Some Microalgal Species by Linear Regression Analysis of Spectrophotometric Measurements

    Directory of Open Access Journals (Sweden)

    Ulf-Peter Hansen

    2007-10-01

    Full Text Available The demonstrated modified spectrophotometric method makes use of the 2,2-diphenyl-1-picrylhydrazyl (DPPH radical and its specific absorbance properties. Theabsorbance decreases when the radical is reduced by antioxidants. In contrast to otherinvestigations, the absorbance was measured at a wavelength of 550 nm. This wavelengthenabled the measurements of the stable free DPPH radical without interference frommicroalgal pigments. This approach was applied to methanolic microalgae extracts for twodifferent DPPH concentrations. The changes in absorbance measured vs. the concentrationof the methanolic extract resulted in curves with a linear decrease ending in a saturationregion. Linear regression analysis of the linear part of DPPH reduction versus extractconcentration enabled the determination of the microalgae’s methanolic extractsantioxidative potentials which was independent to the employed DPPH concentrations. Theresulting slopes showed significant differences (6 - 34 μmol DPPH g-1 extractconcentration between the single different species of microalgae (Anabaena sp.,Isochrysis galbana, Phaeodactylum tricornutum, Porphyridium purpureum, Synechocystissp. PCC6803 in their ability to reduce the DPPH radical. The independency of the signal on the DPPH concentration is a valuable advantage over the determination of the EC50 value.

  11. Determination of mercury species in biological samples by inductively coupled plasma mass spectrometry combined with solvent extraction and ultrasonication

    International Nuclear Information System (INIS)

    Sun, J.; Li, Y.F.; Wang, J.X.; Chen, C.Y.; Li, B.; Gao, Y.X.; Chai, Z.F.

    2005-01-01

    Mercury (Hg) is a well-known toxic element. The toxic effects of Hg depend on its chemical forms. The most important chemical forms are elemental Hg (Hg 0 ), inorganic Hg (Hg 2+ ) and methylmercury (CH 3 Hg + ). In the biogeochemical cycle of Hg, these species may interchange in atmospheric, aquatic and terrestrial environments. Among them, methylmercury is considerably higher toxic than elemental mercury and inorganic mercury because it is recognized as one of major health hazards for human due to its teratogenic, immunotoxic, and neurotoxic effects. Therefore, determinations of not only total mercury, but also methylmercury content in biological samples is necessary. In large numbers of analytical methods, inductively coupled plasma mass spectrometry (ICP-MS) using conventional sample introduction with a peristaltic pump is widely used for the determination of trace metals in a wide variety of different sample matrices. ICP-MS can offer high sensitivity, low detection limit, reasonable accuracy and precision, and can easily be automated. However, mercury is considered as an element with analytical problems. One problem is well known in Hg analysis that the memory effect increases the blank counts and worsens the analytical performance of ICP-MS. The possibility of Hg losses during sample decomposition procedure due to its volatility is another important issue. Additionally, its high first ionization potential and numerous isotopes have limited its sensitivity in ICP-MS analysis. In order to solve the above questions, the present work was carried out to develop a method based on ICP-MS coupled with solvent extraction for determination of mercury species in biological samples. At first step, we investigated different solvent extraction methods including acid leaching, CuSO 4 extraction, alkaline-methanol extraction, and surfactant extraction with ultrasonication for methylmercury determination using the certified reference materials GBW07601 (Human Hair). Next, we

  12. Simultaneous determination of vasicine and vasicinone by High-performance liquid chromatography in roots of eight Sida species.

    Science.gov (United States)

    Subramanya, M D; Pai, Sandeep R; Ankad, Gireesh M; Hegde, Harsha V; Roy, Subarna; Hoti, S L

    2016-01-01

    Sida L. is a medicinally important genus widely used in conventional systems of medicine in India. The present study aims toward simultaneous determination of two bioactive compounds vasicine and vasicinone in root extracts of eight Sida spp. from Western Ghats, India. Determination of vasicine and vasicinone was undertaken in methanolic root extracts (10% w/v) of Sida acuta , Sida cordata , Sida cordifolia , Sida rhombifolia , Sida spinosa , Sida indica , Sida retusa and Sida mysorensis by high performance liquid chromatography (HPLC) method. The standards were prepared with the concentration of mg/mL. Data were expressed as mean values of three reading and relative standard deviations. The separation was achieved on a Waters, Nova-Pack, C18 (250 mm × 4.6 mm, 5 μ) column, with acetonitrile - 0.1 M phosphate buffer-glacial acetic acid (15: 85: 1, v/v/v) as solvent system at a flow-rate of 1.0 mL/min. The effluent was monitored using ultraviolet detection at a wavelength of 300 nm. Both calibration curves of standard showed good linear regression ( R 2 > 0.994). The limit of detection and the limit of quantification for vasicine was 0.110 and 0.333 μg/mL and for vasicinone was 0.059 and 0.179 μg/mL respectively. The vasicine content was highest in S. cordifolia (9.891 ± 0.495 μg/100 mg) and vasicinone content was rich in S. cordata (33.013 ± 1.651 μg/100 mg.) The content of vasicinone was higher than vasicine. HPLC method provides simple, accurate, and reproducible quantitative analysis for simultaneous determination of vasicine and vasicinone. Among the selected Sida species, S. cordifolia and S. cordata were found to be rich in the vasicine and vasicinone contents, respectively.

  13. Determination of ultra trace arsenic species in water samples by hydride generation atomic absorption spectrometry after cloud point extraction

    Energy Technology Data Exchange (ETDEWEB)

    Ulusoy, Halil Ibrahim, E-mail: hiulusoy@yahoo.com [University of Cumhuriyet, Faculty of Science, Department of Chemistry, TR-58140, Sivas (Turkey); Akcay, Mehmet; Ulusoy, Songuel; Guerkan, Ramazan [University of Cumhuriyet, Faculty of Science, Department of Chemistry, TR-58140, Sivas (Turkey)

    2011-10-10

    Graphical abstract: The possible complex formation mechanism for ultra-trace As determination. Highlights: {yields} CPE/HGAAS system for arsenic determination and speciation in real samples has been applied first time until now. {yields} The proposed method has the lowest detection limit when compared with those of similar CPE studies present in literature. {yields} The linear range of the method is highly wide and suitable for its application to real samples. - Abstract: Cloud point extraction (CPE) methodology has successfully been employed for the preconcentration of ultra-trace arsenic species in aqueous samples prior to hydride generation atomic absorption spectrometry (HGAAS). As(III) has formed an ion-pairing complex with Pyronine B in presence of sodium dodecyl sulfate (SDS) at pH 10.0 and extracted into the non-ionic surfactant, polyethylene glycol tert-octylphenyl ether (Triton X-114). After phase separation, the surfactant-rich phase was diluted with 2 mL of 1 M HCl and 0.5 mL of 3.0% (w/v) Antifoam A. Under the optimized conditions, a preconcentration factor of 60 and a detection limit of 0.008 {mu}g L{sup -1} with a correlation coefficient of 0.9918 was obtained with a calibration curve in the range of 0.03-4.00 {mu}g L{sup -1}. The proposed preconcentration procedure was successfully applied to the determination of As(III) ions in certified standard water samples (TMDA-53.3 and NIST 1643e, a low level fortified standard for trace elements) and some real samples including natural drinking water and tap water samples.

  14. Determination of antimicrobial and heavy metal resistance profiles of some bacteria isolated from aquatic amphibian and reptile species.

    Science.gov (United States)

    Hacioglu, Nurcihan; Tosunoglu, Murat

    2014-01-01

    The aim of the present study was to determine the level of antibiotic resistance patterns and distribution of heavy metal resistance of bacterial isolates from aquatic animals (Lissotriton vulgaris, Pelophylax ridibundus, Emys orbicularis, Mauremys rivulata, and Natrix natrix) in Turkey (Kavak Delta). A total of 153 bacteria have been successfully isolated from cloaca and oral samples of the aquatic amphibians and reptilians which were found, namely, Aeromonas sp. (n = 29), Plesiomonas sp. (n = 7), Vibrio sp. (n = 12), Citrobacter sp. (n = 12), Enterobacter sp. (n = 11), Escherichia sp. (n = 22), Klebsiella sp. (n = 22), Edwardsiella sp. (n = 6), Hafnia sp. (n = 1), Proteus sp. (n = 19), Providencia sp. (n = 8), and Pseudomonas sp. (n = 4). In terms of antibiotic and heavy metal susceptibility testing, each isolate was tested against 12 antibiotics and 4 metals. There was a high incidence of resistance to cefoxitin (46.40 %), ampicillin (44.44 %), erythromycin (35.29 %), and a low incidence of resistance to gentamicin (6.53 %), kanamycin (8.49 %), chloramphenicol (9.15 %), and cefotaxime (10.45 %). The multiple antibiotic resistance index of each bacterial species indicated that bacteria from raised amphibians and reptiles have been exposed to tested antibiotics, with results ranging from 0 to 0.58. Most isolates showed tolerance to different concentrations of heavy metals, and minimal inhibition concentrations ranged from100 to >3,200 μg/mL. According to these results, a significant occurrence of bacteria in the internal organs of reptiles and amphibians, with a high incidence of resistance against antibiotics and heavy metals, may risk aquatic animals and the public health. These data appoint the importance of epidemiological surveillance and microbiological monitoring and reinforce the need to implement environment protection programs for amphibian and reptile species.

  15. Trait characteristics determine pyrethroid sensitivity in non-standard test species of freshwater macroinvertebrates – A reality check

    DEFF Research Database (Denmark)

    Wiberg-Larsen, Peter; Graeber, Daniel; Baattrup-Pedersen, Annette

    2016-01-01

    was recorded using automated video tracking. Most arthropod species showed mortality responses to the exposure concentrations (0.01-10 μg L(-1)), whereas nonarthropod species remained unaffected. LC50 varied by at least a factor of 1000 among arthropod species, even within the same family. This variation could...

  16. Determinants of public support for threatened and endangered species management: A case study of Cape Lookout National Seashore

    Science.gov (United States)

    Le, Lena; Bagstad, Kenneth J.; Cook, Philip S.; Leong, Kirsten M.; DiDonato, Eva

    2015-01-01

    Gaining public support for management actions is important to the success of public land management agencies’ efforts to protect threatened and endangered species. This is especially relevant at national parks, where managers balance two aspects of their conservation mission: to protect resources and to provide for public enjoyment. This study examined variables potentially associated with support for management actions at Cape Lookout National Seashore, a unit of the National Park Service. Two visitor surveys were conducted at the park at different seasons, and a resident survey was conducted for households in Carteret County, North Carolina, where the park is located. The goal of the project was to provide park managers with information that may help with the development of communication strategies concerning the park’s conservation mission. These communication strategies may help to facilitate mutual understanding and garner public support for management actions. Several variables were examined as potential determinants that park managers ought to consider when developing communication strategies. Multinomial logistic regression was applied to examine the relationships between these variables and the likelihood of support for or opposition to management actions. The variables examined included perceived shared values of park resources, general environmental attitudes, level of familiarity with park resources and regulations, knowledge about threatened and endangered species, level of trust in the decision-making process, and perceived shared values with park management. In addition, demographic variables such as income level, respondent age, residency status, and visitor type were also used. The results show that perceived values of threatened and endangered species, trust in park managers and the decision-making process, and perceived share values with park managers were among the strongest indicators of support for management actions. Different user groups

  17. Primary structure and conformational analysis of peptide methionine-tyrosine, a peptide related to neuropeptide Y and peptide YY isolated from lamprey intestine

    DEFF Research Database (Denmark)

    Conlon, J M; Bjørnholm, B; Jørgensen, Flemming Steen

    1991-01-01

    A peptide belonging to the pancreatic-polypeptide-fold family of regulatory peptides has been isolated from the intestine of an Agnathan, the sea lamprey (Petromyzon marinus). The primary structure of the peptide (termed peptide methionine-tyrosine) was established as Met-Pro-Pro-Lys-Pro-Asp-Asn-...... in a preferred structure in which the conformation of the beta-turn between the two helical domains (residues 9-14) is appreciably different....

  18. The influence of acclimation temperature on the lipid composition of the larval lamprey, Petromyzon marinus, depends on tissue and lipid class.

    Science.gov (United States)

    Kao, Yung-Hsi; Sheridan, Mark A; Holmes, John A; Youson, John H

    2010-11-01

    This study was designed to examine the effect of thermal acclimation on the lipid composition of fat depot organs the liver and kidneys of larval sea lamprey, Petromyzon marinus. We found that 21 °C-acclimated larvae possessed lower total lipid amounts in the liver (39% lower) and kidneys (30% lower) than 13 °C-acclimated larvae. Relatively lower lipid contents in the liver and kidneys of 21 °C-acclimated lamprey primarily resulted from a reduction in stored lipid reserve, triacylglycerol, but not the structural lipid, phospholipid. Compared to 21 °C-acclimated larvae, 13 °C-acclimated larvae were found to possess fewer saturated fatty acids (SFAs) and more unsaturated fatty acids (USFAs) in renal triacylglycerol and phospholipid classes, while there were no significant differences in the SFAs and USFAs of hepatic triacylglycerol, phospholipid, cholesteryl ester, fatty acid, and monoacylglycerol classes. Fewer SFAs, found in the kidney triacylglycerol of 13 °C-acclimated lamprey, were due to lower 12:0 and 14:0 fatty acids, but those in the renal phospholipid class were characterized by fewer 14:0, 15:0, and 16:0 fatty acids. More USFAs in renal triacylglycerol, as indicated by a higher unsaturation index, primarily resulted from higher polyunsaturated fatty acids (18:2ω6, 18:3ω3, and 18:4ω3); whereas, in the renal phospholipid class, this was a result of higher monoenes (18:1, 20:1, and 22:1ω9) and ω3 polyunsaturated fatty acids (18:4ω3). These data suggest that the influence of thermal acclimation on the lipid composition of lamprey fat depot organs depends on tissue and lipid class.

  19. Bayesian phylogeny analysis of vertebrate serpins illustrates evolutionary conservation of the intron and indels based six groups classification system from lampreys for ∼500 MY

    Directory of Open Access Journals (Sweden)

    Abhishek Kumar

    2015-06-01

    Full Text Available The serpin superfamily is characterized by proteins that fold into a conserved tertiary structure and exploits a sophisticated and irreversible suicide-mechanism of inhibition. Vertebrate serpins are classified into six groups (V1–V6, based on three independent biological features—genomic organization, diagnostic amino acid sites and rare indels. However, this classification system was based on the limited number of mammalian genomes available. In this study, several non-mammalian genomes are used to validate this classification system using the powerful Bayesian phylogenetic method. This method supports the intron and indel based vertebrate classification and proves that serpins have been maintained from lampreys to humans for about 500 MY. Lampreys have fewer than 10 serpins, which expand into 36 serpins in humans. The two expanding groups V1 and V2 have SERPINB1/SERPINB6 and SERPINA8/SERPIND1 as the ancestral serpins, respectively. Large clusters of serpins are formed by local duplications of these serpins in tetrapod genomes. Interestingly, the ancestral HCII/SERPIND1 locus (nested within PIK4CA possesses group V4 serpin (A2APL1, homolog of α2-AP/SERPINF2 of lampreys; hence, pointing to the fact that group V4 might have originated from group V2. Additionally in this study, details of the phylogenetic history and genomic characteristics of vertebrate serpins are revisited.

  20. Determination of butyltin species in natural waters using aqueous phase ethylation and off-line room temperature trapping

    International Nuclear Information System (INIS)

    Bowles, Karl C.; Apte, Simon C.; Hales, Leigh T.

    2003-01-01

    Monobutyltin (MBT), dibutyltin (DBT) and tributyltin (TBT) were determined in natural water samples by aqueous phase ethylation with sodium tetraethylborate (STEB), room temperature trapping of the resulting volatile derivatives on Tenax TA[reg], followed by gas chromatography-quartz furnace atomic absorption spectrometry (GC-QFAAS). Recoveries of butyltin spikes from natural water samples were 90-109% at concentrations of ∼100 ng Sn/l. The method precision at ∼100 ng Sn/l was ≤6% RSD for butyltins spiked into natural waters. The detection limits for 1 l water samples were <1 ng Sn/l for all butyltin species. Sample throughput of the method is high (greater than three samples per hour) due to the two-stage nature of the procedure, which allows derivatisation/trapping and GC-QFAAS quantitation to be performed separately. Off-line trapping is also advantageous as it extends the life of the GC column and quartz furnace to at least 12 months due to minimisation of carry-over of co-purged material

  1. Heavy Metals (Mercury, Lead and Cadmium Determination in 17 Species of Fish Marketed in Khorramabad City, West of Iran

    Directory of Open Access Journals (Sweden)

    Ali Mortazavi

    2016-01-01

    Full Text Available Heavy metals entrance to fish body tissues and transferring to human body systems after their consuming makes numerous undesirable effects and health problems. The aim of this study was to determine some heavy metals (lead, cadmium and mercury in fresh fishes marketed in Khorramabad City, west of Iran. In this descriptive study, five samples of 17 fish species with high consumption were purchased randomly in 2014. Measurement of mercury, lead and cadmium was performed using atomic absorption spectrometry. All measurements were performed three times for each sample. Lead mean levels in fish samples was in the range 0.736 -1.005 ppm, cadmium range was from 0.196 to 0.015 ppm and mean content of mercury was  0.431 - 0.107 ppm. At present mean concentration of lead, mercury and cadmium in supplied fishes muscle is lower than maximum recommended levels according to WHO, EC and FDA guidelines. Based on the obtained results of this study and the importance of heavy metals in foods and their impacts on human health, continuous monitoring of heavy metals levels in foods is necessary.

  2. Determination of Germination Response to Temperature and Water Potential for a Wide Range of Cover Crop Species and Related Functional Groups.

    Science.gov (United States)

    Tribouillois, Hélène; Dürr, Carolyne; Demilly, Didier; Wagner, Marie-Hélène; Justes, Eric

    2016-01-01

    A wide range of species can be sown as cover crops during fallow periods to provide various ecosystem services. Plant establishment is a key stage, especially when sowing occurs in summer with high soil temperatures and low water availability. The aim of this study was to determine the response of germination to temperature and water potential for diverse cover crop species. Based on these characteristics, we developed contrasting functional groups that group species with the same germination ability, which may be useful to adapt species choice to climatic sowing conditions. Germination of 36 different species from six botanical families was measured in the laboratory at eight temperatures ranging from 4.5-43°C and at four water potentials. Final germination percentages, germination rate, cardinal temperatures, base temperature and base water potential were calculated for each species. Optimal temperatures varied from 21.3-37.2°C, maximum temperatures at which the species could germinate varied from 27.7-43.0°C and base water potentials varied from -0.1 to -2.6 MPa. Most cover crops were adapted to summer sowing with a relatively high mean optimal temperature for germination, but some Fabaceae species were more sensitive to high temperatures. Species mainly from Poaceae and Brassicaceae were the most resistant to water deficit and germinated under a low base water potential. Species were classified, independent of family, according to their ability to germinate under a range of temperatures and according to their base water potential in order to group species by functional germination groups. These groups may help in choosing the most adapted cover crop species to sow based on climatic conditions in order to favor plant establishment and the services provided by cover crops during fallow periods. Our data can also be useful as germination parameters in crop models to simulate the emergence of cover crops under different pedoclimatic conditions and crop

  3. Species composition of the genus Saprolegnia in fin fish aquaculture environments, as determined by nucleotide sequence analysis of the nuclear rDNA ITS regions.

    Science.gov (United States)

    de la Bastide, Paul Y; Leung, Wai Lam; Hintz, William E

    2015-01-01

    The ITS region of the rDNA gene was compared for Saprolegnia spp. in order to improve our understanding of nucleotide sequence variability within and between species of this genus, determine species composition in Canadian fin fish aquaculture facilities, and to assess the utility of ITS sequence variability in genetic marker development. From a collection of more than 400 field isolates, ITS region nucleotide sequences were studied and it was determined that there was sufficient consistent inter-specific variation to support the designation of species identity based on ITS sequence data. This non-subjective approach to species identification does not rely upon transient morphological features. Phylogenetic analyses comparing our ITS sequences and species designations with data from previous studies generally supported the clade scheme of Diéguez-Uribeondo et al. (2007) and found agreement with the molecular taxonomic cluster system of Sandoval-Sierra et al. (2014). Our Canadian ITS sequence collection will thus contribute to the public database and assist the clarification of Saprolegnia spp. taxonomy. The analysis of ITS region sequence variability facilitated genus- and species-level identification of unknown samples from aquaculture facilities and provided useful information on species composition. A unique ITS-RFLP for the identification of S. parasitica was also described. Copyright © 2014 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  4. Morphological identification and COI barcodes of adult flies help determine species identities of chironomid larvae (Diptera, Chironomidae).

    Science.gov (United States)

    Failla, A J; Vasquez, A A; Hudson, P; Fujimoto, M; Ram, J L

    2016-02-01

    Establishing reliable methods for the identification of benthic chironomid communities is important due to their significant contribution to biomass, ecology and the aquatic food web. Immature larval specimens are more difficult to identify to species level by traditional morphological methods than their fully developed adult counterparts, and few keys are available to identify the larval species. In order to develop molecular criteria to identify species of chironomid larvae, larval and adult chironomids from Western Lake Erie were subjected to both molecular and morphological taxonomic analysis. Mitochondrial cytochrome c oxidase I (COI) barcode sequences of 33 adults that were identified to species level by morphological methods were grouped with COI sequences of 189 larvae in a neighbor-joining taxon-ID tree. Most of these larvae could be identified only to genus level by morphological taxonomy (only 22 of the 189 sequenced larvae could be identified to species level). The taxon-ID tree of larval sequences had 45 operational taxonomic units (OTUs, defined as clusters with >97% identity or individual sequences differing from nearest neighbors by >3%; supported by analysis of all larval pairwise differences), of which seven could be identified to species or 'species group' level by larval morphology. Reference sequences from the GenBank and BOLD databases assigned six larval OTUs with presumptive species level identifications and confirmed one previously assigned species level identification. Sequences from morphologically identified adults in the present study grouped with and further classified the identity of 13 larval OTUs. The use of morphological identification and subsequent DNA barcoding of adult chironomids proved to be beneficial in revealing possible species level identifications of larval specimens. Sequence data from this study also contribute to currently inadequate public databases relevant to the Great Lakes region, while the neighbor

  5. Species specific isotope dilution for the accurate and SI traceable determination of arsenobetaine and methylmercury in cuttlefish and prawn

    Energy Technology Data Exchange (ETDEWEB)

    Kumkrong, Paramee [National Research Council Canada, 1200 Montreal Rd, Ottawa, Ontario, K1A 0R6 (Canada); Thailand Institute of Scientific and Technological Research, 35 Mu 3 Tambon Khlong Ha, Amphoe Khlong Luang, Pathum Thani, 12120 (Thailand); Thiensong, Benjaporn [Thailand Institute of Scientific and Technological Research, 35 Mu 3 Tambon Khlong Ha, Amphoe Khlong Luang, Pathum Thani, 12120 (Thailand); Le, Phuong Mai; McRae, Garnet; Windust, Anthony [National Research Council Canada, 1200 Montreal Rd, Ottawa, Ontario, K1A 0R6 (Canada); Deawtong, Suladda [Thailand Institute of Scientific and Technological Research, 35 Mu 3 Tambon Khlong Ha, Amphoe Khlong Luang, Pathum Thani, 12120 (Thailand); Meija, Juris; Maxwell, Paulette [National Research Council Canada, 1200 Montreal Rd, Ottawa, Ontario, K1A 0R6 (Canada); Yang, Lu, E-mail: Lu.yang@nrc-cnrc.gc.ca [National Research Council Canada, 1200 Montreal Rd, Ottawa, Ontario, K1A 0R6 (Canada); Mester, Zoltán [National Research Council Canada, 1200 Montreal Rd, Ottawa, Ontario, K1A 0R6 (Canada)

    2016-11-02

    Methods based on species specific isotope dilution were developed for the accurate and SI traceable determination of arsenobetaine (AsBet) and methylmercury (MeHg) in prawn and cuttlefish tissues by LC-MS/MS and SPME GC-ICPMS. Quantitation of AsBet and MeHg were achieved by using a {sup 13}C-enriched AsBet spike (NRC CRM CBET-1) and an enriched spike of Me{sup 198}Hg (NRC CRM EMMS-1), respectively, wherein analyte mass fractions in enriched spikes were determined by reverse isotope dilution using natural abundance AsBet and MeHg primary standards. Purity of these primary standards were characterized by quantitative {sup 1}H-NMR with the use of NIST SRM 350b benzoic acid as a primary calibrator, ensuring the final measurement results traceable to SI. Validation of employed methods of ID LC-MS/MS and ID SPME GC-ICPMS was demonstrated by analysis of several biological CRMs (DORM-4, TORT-3, DOLT-5, BCR-627 and BCR-463) with satisfying results. The developed methods were applied for the determination of AsBet and MeHg in two new certified reference materials (CRMs) prawn (PRON-1) and cuttlefish (SQID-1) produced jointly by Thailand Institute of Scientific and Technological Research (TISTR) and National Research Council Canada (NRC). With additional measurements of AsBet using LC-ICPMS with standard additions calibration and external calibration at NRC and TISTR, respectively, certified values of 1.206 ± 0.058 and 13.96 ± 0.54 mg kg{sup −1} for AsBet as As (expanded uncertainty, k = 2) were obtained for the new CRMs PRON-1 and SQID-1, respectively. The reference value of 0.324 ± 0.028 mg kg{sup −1} as Hg (expanded uncertainty, k = 2) for MeHg was obtained for the SQID-1 based on the results obtained by ID SPME GC-ICPMS method only, whereas MeHg in PRON-1 was found to be < 0.015 mg kg{sup −1}. It was found that AsBet comprised 69.7% and 99.0% of total As in the prawn and cuttlefish, respectively, whereas MeHg comprised 94.5% of total Hg in

  6. Species specific isotope dilution for the accurate and SI traceable determination of arsenobetaine and methylmercury in cuttlefish and prawn

    International Nuclear Information System (INIS)

    Kumkrong, Paramee; Thiensong, Benjaporn; Le, Phuong Mai; McRae, Garnet; Windust, Anthony; Deawtong, Suladda; Meija, Juris; Maxwell, Paulette; Yang, Lu; Mester, Zoltán

    2016-01-01

    Methods based on species specific isotope dilution were developed for the accurate and SI traceable determination of arsenobetaine (AsBet) and methylmercury (MeHg) in prawn and cuttlefish tissues by LC-MS/MS and SPME GC-ICPMS. Quantitation of AsBet and MeHg were achieved by using a "1"3C-enriched AsBet spike (NRC CRM CBET-1) and an enriched spike of Me"1"9"8Hg (NRC CRM EMMS-1), respectively, wherein analyte mass fractions in enriched spikes were determined by reverse isotope dilution using natural abundance AsBet and MeHg primary standards. Purity of these primary standards were characterized by quantitative "1H-NMR with the use of NIST SRM 350b benzoic acid as a primary calibrator, ensuring the final measurement results traceable to SI. Validation of employed methods of ID LC-MS/MS and ID SPME GC-ICPMS was demonstrated by analysis of several biological CRMs (DORM-4, TORT-3, DOLT-5, BCR-627 and BCR-463) with satisfying results. The developed methods were applied for the determination of AsBet and MeHg in two new certified reference materials (CRMs) prawn (PRON-1) and cuttlefish (SQID-1) produced jointly by Thailand Institute of Scientific and Technological Research (TISTR) and National Research Council Canada (NRC). With additional measurements of AsBet using LC-ICPMS with standard additions calibration and external calibration at NRC and TISTR, respectively, certified values of 1.206 ± 0.058 and 13.96 ± 0.54 mg kg"−"1 for AsBet as As (expanded uncertainty, k = 2) were obtained for the new CRMs PRON-1 and SQID-1, respectively. The reference value of 0.324 ± 0.028 mg kg"−"1 as Hg (expanded uncertainty, k = 2) for MeHg was obtained for the SQID-1 based on the results obtained by ID SPME GC-ICPMS method only, whereas MeHg in PRON-1 was found to be < 0.015 mg kg"−"1. It was found that AsBet comprised 69.7% and 99.0% of total As in the prawn and cuttlefish, respectively, whereas MeHg comprised 94.5% of total Hg in cuttlefish. - Highlights:

  7. Pattern or process? Evaluating the peninsula effect as a determinant of species richness in coastal dune forests.

    Directory of Open Access Journals (Sweden)

    Pieter I Olivier

    Full Text Available The peninsula effect predicts that the number of species should decline from the base of a peninsula to the tip. However, evidence for the peninsula effect is ambiguous, as different analytical methods, study taxa, and variations in local habitat or regional climatic conditions influence conclusions on its presence. We address this uncertainty by using two analytical methods to investigate the peninsula effect in three taxa that occupy different trophic levels: trees, millipedes, and birds. We surveyed 81 tree quadrants, 102 millipede transects, and 152 bird points within 150 km of coastal dune forest that resemble a habitat peninsula along the northeast coast of South Africa. We then used spatial (trend surface analyses and non-spatial regressions (generalized linear mixed models to test for the presence of the peninsula effect in each of the three taxa. We also used linear mixed models to test if climate (temperature and precipitation and/or local habitat conditions (water availability associated with topography and landscape structural variables could explain gradients in species richness. Non-spatial models suggest that the peninsula effect was present in all three taxa. However, spatial models indicated that only bird species richness declined from the peninsula base to the peninsula tip. Millipede species richness increased near the centre of the peninsula, while tree species richness increased near the tip. Local habitat conditions explained species richness patterns of birds and trees, but not of millipedes, regardless of model type. Our study highlights the idiosyncrasies associated with the peninsula effect-conclusions on the presence of the peninsula effect depend on the analytical methods used and the taxon studied. The peninsula effect might therefore be better suited to describe a species richness pattern where the number of species decline from a broader habitat base to a narrow tip, rather than a process that drives species

  8. Genetic calibration of species diversity among North America's freshwater fishes.

    Science.gov (United States)

    April, Julien; Mayden, Richard L; Hanner, Robert H; Bernatchez, Louis

    2011-06-28

    Freshwater ecosystems are being heavily exploited and degraded by human activities all over the world, including in North America, where fishes and fisheries are strongly affected. Despite centuries of taxonomic inquiry, problems inherent to species identification continue to hamper the conservation of North American freshwater fishes. Indeed, nearly 10% of species diversity is thought to remain undescribed. To provide an independent calibration of taxonomic uncertainty and to establish a more accessible molecular identification key for its application, we generated a standard reference library of mtDNA sequences (DNA barcodes) derived from expert-identified museum specimens for 752 North American freshwater fish species. This study demonstrates that 90% of known species can be delineated using barcodes. Moreover, it reveals numerous genetic discontinuities indicative of independently evolving lineages within described species, which points to the presence of morphologically cryptic diversity. From the 752 species analyzed, our survey flagged 138 named species that represent as many as 347 candidate species, which suggests a 28% increase in species diversity. In contrast, several species of parasitic and nonparasitic lampreys lack such discontinuity and may represent alternative life history strategies within single species. Therefore, it appears that the current North American freshwater fish taxonomy at the species level significantly conceals diversity in some groups, although artificially creating diversity in others. In addition to providing an easily accessible digital identification system, this study identifies 151 fish species for which taxonomic revision is required.

  9. A study on the determination of the morphological, yield and quality characteristics of some sainfoin species (onobrychis spp.) native to east anatolia

    International Nuclear Information System (INIS)

    Okcu, M.; Sengul, S.

    2014-01-01

    Objective of the present study is to identify the species belonging to the genus Onobrychis (Fabaceae) growing native in and around Erzurum, and to determine their overall prevalence and morphological and quality characteristics. Species samples were collected from different locations in flowering periods of 2007, 2008 and 2009. At the end of the study, totally 10 genotypes were found representing 8 species and 2 sub-species. It was found that leaf length and leaflet frequency were the largest in O. atropatana var. grandiflora, the number of leaflets was the highest in O. viciifolia, the length and width of leaflets were maximum in O. radiata, the number of main branches and the number of fascicles in main branches were in O. hajastana, crude ash rate was highest in O. stenostachya, plant fresh and dry weight, ADF and NDF rate were highest in O. cornuta, where as crude protein rate was slightly higher in O. stenostachya subsp. sosnowskyi than other taxa. (author)

  10. Biogenic volatile organic compound (BVOC) emissions from forested areas in Turkey: Determination of specific emission rates for thirty-one tree species

    International Nuclear Information System (INIS)

    Aydin, Yagmur Meltem; Yaman, Baris; Koca, Husnu; Dasdemir, Okan; Kara, Melik; Altiok, Hasan; Dumanoglu, Yetkin; Bayram, Abdurrahman; Tolunay, Doganay; Odabasi, Mustafa; Elbir, Tolga

    2014-01-01

    Normalized biogenic volatile organic compound (BVOC) emission rates for thirty one tree species that cover the 98% of national forested areas in Turkey were determined. Field samplings were performed at fourteen different forested areas in Turkey using a specific dynamic enclosure system. The selected branches of tree species were enclosed in a chamber consisted of a transparent Nalofan bag. The air-flows were sampled from both inlet and outlet of the chamber by Tenax-filled sorbent tubes during photosynthesis of trees under the presence of sunlight. Several environmental parameters (temperature, humidity, photosynthetically active radiation-PAR, and CO 2 ) were continuously monitored inside and outside the enclosure chamber during the samplings. Collected samples were analyzed using a gas chromatography mass spectrometry (GC/MS) system equipped with a thermal desorber (TD). Sixty five BVOCs classified in five major groups (isoprene, monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, and other oxygenated compounds) were analyzed. Emission rates were determined by normalization to standard conditions (1000 μmol/m 2 s PAR and 30 °C temperature for isoprene and 30 °C temperature for the remaining compounds). In agreement with the literature, isoprene was mostly emitted by broad-leaved trees while coniferous species mainly emitted monoterpenes. Several tree species such as Sweet Chestnut, Silver Lime, and European Alder had higher monoterpene emissions although they are broad-leaved species. High isoprene emissions were also observed for a few coniferous species such as Nordmann Fir and Oriental Spruce. The highest normalized total BVOC emission rate of 27.1 μg/g h was observed for Oriental Plane while South European Flowering Ash was the weakest BVOC emitter with a total normalized emission rate of 0.031 μg/g h. Monoterpene emissions of broad-leaved species mainly consisted of sabinene, limonene and trans-beta-ocimene, while alpha-pinene, beta-pinene and

  11. Biogenic volatile organic compound (BVOC) emissions from forested areas in Turkey: Determination of specific emission rates for thirty-one tree species

    Energy Technology Data Exchange (ETDEWEB)

    Aydin, Yagmur Meltem; Yaman, Baris; Koca, Husnu; Dasdemir, Okan; Kara, Melik; Altiok, Hasan; Dumanoglu, Yetkin; Bayram, Abdurrahman [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir (Turkey); Tolunay, Doganay [Department of Soil Science and Ecology, Faculty of Forestry, Istanbul University, Bahcekoy, Istanbul (Turkey); Odabasi, Mustafa [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir (Turkey); Elbir, Tolga, E-mail: tolga.elbir@deu.edu.tr [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir (Turkey)

    2014-08-15

    Normalized biogenic volatile organic compound (BVOC) emission rates for thirty one tree species that cover the 98% of national forested areas in Turkey were determined. Field samplings were performed at fourteen different forested areas in Turkey using a specific dynamic enclosure system. The selected branches of tree species were enclosed in a chamber consisted of a transparent Nalofan bag. The air-flows were sampled from both inlet and outlet of the chamber by Tenax-filled sorbent tubes during photosynthesis of trees under the presence of sunlight. Several environmental parameters (temperature, humidity, photosynthetically active radiation-PAR, and CO{sub 2}) were continuously monitored inside and outside the enclosure chamber during the samplings. Collected samples were analyzed using a gas chromatography mass spectrometry (GC/MS) system equipped with a thermal desorber (TD). Sixty five BVOCs classified in five major groups (isoprene, monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, and other oxygenated compounds) were analyzed. Emission rates were determined by normalization to standard conditions (1000 μmol/m{sup 2} s PAR and 30 °C temperature for isoprene and 30 °C temperature for the remaining compounds). In agreement with the literature, isoprene was mostly emitted by broad-leaved trees while coniferous species mainly emitted monoterpenes. Several tree species such as Sweet Chestnut, Silver Lime, and European Alder had higher monoterpene emissions although they are broad-leaved species. High isoprene emissions were also observed for a few coniferous species such as Nordmann Fir and Oriental Spruce. The highest normalized total BVOC emission rate of 27.1 μg/g h was observed for Oriental Plane while South European Flowering Ash was the weakest BVOC emitter with a total normalized emission rate of 0.031 μg/g h. Monoterpene emissions of broad-leaved species mainly consisted of sabinene, limonene and trans-beta-ocimene, while alpha-pinene, beta

  12. Flow regime in a restored wetland determines trophic links and species composition in the aquatic macroinvertebrate community.

    Science.gov (United States)

    González-Ortegón, E; Walton, M E M; Moghaddam, B; Vilas, C; Prieto, A; Kennedy, H A; Pedro Cañavate, J; Le Vay, L

    2015-01-15

    In a restored wetland (South of Spain), where different flow regimes control water exchange with the adjacent Guadalquivir estuary, the native Palaemon varians coexists with an exotic counterpart species Palaemon macrodactylus. This controlled m\\acrocosm offers an excellent opportunity to investigate how the effects of water management, through different flow regimes, and the presence of a non-native species affect the aquatic community and the trophic niche (by gut contents and C-N isotopic composition) of the native shrimp Palaemon varians. We found that increased water exchange rate (5% day(-1) in mixed ponds vs. 0.1% day(-1) in extensive ponds) modified the aquatic community of this wetland; while extensive ponds are dominated by isopods and amphipods with low presence of P. macrodactylus, mixed ponds presented high biomass of mysids, corixids, copepods and both shrimp species. An estuarine origin of nutrients and primary production might explain seasonal and spatial differences found among ponds of this wetland. A combined analysis of gut contents and isotopic composition of the native and the exotic species showed that: (1) native P. varians is mainly omnivorous (2) while the non-native P. macrodactylus is more zooplanktivorous and (3) a dietary overlap occurred when both species coexist at mixed ponds where a higher water exchange and high abundance of mysids and copepods diversifies the native species' diet. Thus differences in the trophic ecology of both species are clearly explained by water management. This experimental study is a valuable tool for integrated management between river basin and wetlands since it allows quantification of wetland community changes in response to the flow regime. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. High-Resolution Nuclear Magnetic Resonance Determination of Transfer RNA Tertiary Base Pairs in Solution. 2. Species Containing a Large Variable Loop

    NARCIS (Netherlands)

    HURD, RE; ROBILLARD, GT; REID, BR

    1977-01-01

    The number of base pairs in the solution structure of several class III D3VN tRNA species from E. coli has been determined by analyzing the number of low-field (-15 to -11 ppm) proton resonances in their nuclear magnetic resonance spectra at 360 MHz. Contrary to previous reports indicating the

  14. Egg hatchability in high Arctic breeding wader species Charadriiformes is not affected by determining incubation stage using the egg flotation technique

    NARCIS (Netherlands)

    Hansen, Jannik; Schmidt, Niels Martin; Reneerkens, Jeroen

    2011-01-01

    Capsule By following the fate of both floated and non-floated eggs from individual clutches of four Arctic wader (shorebird) species, we show that the use of the flotation method for determining incubation stage of eggs (which involves both the submersion and handling of eggs) does not negatively

  15. Quantitative determination of curcuminoids from the Roots of Curcuma longa, Curcuma species and dietary supplements using an UPLC-UV-MS method

    Science.gov (United States)

    A simple, fast UPLC-UV-MS method was developed for the determination of curcuminoids from roots of Curcuma longa L., Curcuma species (C. zedoaria, C. phaecaulis, C. wenyujin and C. kwangsiensis) and dietary supplements claiming to contain C. longa. The total content of curcuminoids (curcumin, desmet...

  16. Culicoides Species Communities Associated with Wild Ruminant Ecosystems in Spain: Tracking the Way to Determine Potential Bridge Vectors for Arboviruses.

    Directory of Open Access Journals (Sweden)

    Sandra Talavera

    Full Text Available The genus Culicoides Latreille 1809 is a well-known vector for protozoa, filarial worms and, above all, numerous viruses. The Bluetongue virus (BTV and the recently emerged Schmallenberg virus (SBV are responsible for important infectious, non-contagious, insect-borne viral diseases found in domestic ruminants and transmitted by Culicoides spp. Both of these diseases have been detected in wild ruminants, but their role as reservoirs during the vector-free season still remains relatively unknown. In fact, we tend to ignore the possibility of wild ruminants acting as a source of disease (BTV, SBV and permitting its reintroduction to domestic ruminants during the following vector season. In this context, a knowledge of the composition of the Culicoides species communities that inhabit areas where there are wild ruminants is of major importance as the presence of a vector species is a prerequisite for disease transmission. In this study, samplings were conducted in areas inhabited by different wild ruminant species; samples were taken in both 2009 and 2010, on a monthly basis, during the peak season for midge activity (in summer and autumn. A total of 102,693 specimens of 40 different species of the genus Culicoides were trapped; these included major BTV and SBV vector species. The most abundant vector species were C. imicola and species of the Obsoletus group, which represented 15% and 11% of total numbers of specimens, respectively. At the local scale, the presence of major BTV and SBV vector species in areas with wild ruminants coincided with that of the nearest sentinel farms included in the Spanish Bluetongue Entomological Surveillance Programme, although their relative abundance varied. The data suggest that such species do not exhibit strong host specificity towards either domestic or wild ruminants and that they could consequently play a prominent role as bridge vectors for different pathogens between both types of ruminants. This finding

  17. Determination of the elemental composition of some lesser-used Ghanaian wood species by neutron activation analysis

    International Nuclear Information System (INIS)

    Nyarko, B.J.B.; Serfor-Armah, Y.; Adomako, D.; Andam, A.A.B.; Addison, E.C.K.; Ofori, J.; Cobbinah, J.R.

    2003-01-01

    Wood plays an undisputed socio-economic role in human endeavour. The elemental composition of wood can give an indication of the environmental pollution of the locality from which the wood sample was extracted as timber, and can influence the machining characteristics of timber. Additionally, the elemental composition can be used as an index of the nutrient uptake of plants from the soil. With the over-exploitation of timber species in Ghana, it is now imperative that lesser-used species are studied to know their characteristics for utilization. We report preliminary results of a study on the elemental composition of some lesser-used Ghanaian wood species. Ten Ghana wood species had been studied, namely: Strombosia glauscens, Lophira alata, Cynometra anata, Combretodendron macrocarpum, Sterculia rhinopetala, Celtis milbraedii, Celtis zenteri, Nesogoadonia papaverifa, Nauclea diderrichii, and Piptadeniastrum afrieana. Neutron activation analysis was carried out for this work, using the Ghana Research Reactor, (GHARRI) facility, operating between 3-15kw and at a thermal neutron flux of 1-5 x 10 15 ns -1 cm 2 . A total of twenty-five elements were identified, some at high level, others at trace levels. We discuss the implications of these results for the efficient utilization of lesser-used Ghana wood species (author)

  18. Video-Based Electroshocking Platform to Identify Lamprey Ammocoete Habitats: Field Validation and New Discoveries in the Columbia River Basin

    Energy Technology Data Exchange (ETDEWEB)

    Arntzen, Evan V.; Mueller, Robert P.

    2017-05-04

    A deep water electroshocking platform (DEP), developed to characterize larval lampreys (ammocoetes) and associated habitat in depths up to 15 m, was recently tested in the field. The DEP samples 0.55 m2∙min-1 without requiring ammocoete transport to the surface. Searches were conducted at a known rearing location (mouth of the Wind River, WA) and at locations on the Cowlitz River, WA, where ammocoetes had not previously been found. At the mouth of the Wind River, video imaged ammocoetes ranged from 50 to 150 mm in water depths between 1.5 m and 4.5 m and were more common in sediments containing organic silt. Ammocoetes (n=137) were detected at 61% of locations sampled (summer) and 50% of the locations sampled (winter). Following the field verification, the DEP was used on the lower 11.7 km of the Cowlitz River, WA. Ammocoetes (n=41) were found with a detection rate of 26% at specific search locations. Cowlitz River sediment containing ammocoetes was also dominated by silt with organic material, often downstream of alluvial bars in water depths from 0.8 to 1.7 m. Test results indicated a high sampling efficiency, favorable detection rates, and little or no impact to ammocoetes and their surrounding benthic environments.

  19. Evaluating potential artefacts of photo-reversal on behavioral studies with nocturnal invasive sea lamprey (Petromyzon marinus)

    Science.gov (United States)

    Barnett, Matthew; Imre, Istvan; Wagner, Michael C.; Di Rocco, Richard T.; Johnson, Nicholas; Brown, Grant E.

    2016-01-01

    Sea lampreys (Petromyzon marinus L., 1758) are nocturnal, so experiments evaluating their behaviour to chemosensory cues have typically been conducted at night. However, given the brief timeframe each year that adult P. marinus are available for experimentation, we investigated whether P. marinus exposed to a 12 h shifted diurnal cycle (reversed photoperiod) could be tested in a darkened arena during the day and show the same response to chemosensory cues as natural photoperiod P. marinus that were tested during the night. Ten replicates of 10 P. marinus, from each photoperiod, were exposed to deionized water (negative control), 2-phenylethylamine hydrochloride (PEA HCl, putative predator cue), or P. marinus whole-body extract (conspecific alarm cue). All P. marinus demonstrated a significant avoidance response to both cues. No significant differences were found in avoidance to PEA HCl between photoperiods. Avoidance of P. marinus whole-body extract was significantly stronger in natural compared with reversed photoperiod P. marinus. The use of reversed photoperiod subjects is suitable for examining the presence or absence of avoidance in response to novel chemosensory alarm cues, or the change in the magnitude of antipredator response. Studies investigating the natural magnitude of antipredator response should use natural photoperiod experimental subjects.

  20. Determinants of palm species distributions across Africa: the relative roles of climate, non-climatic environmental factors, and spatial constraints

    DEFF Research Database (Denmark)

    Overgaard, Anne Blach; Svenning, J.-C.; Dransfield, John

    2010-01-01

    -climatic environmental predictors, the latter having no discernible effect beyond the climatic control. Hence, at the continental scale, climate constitutes the only strong environmental control of palm species distributions in Africa. With regard to the most important climatic predictors of African palm distributions......, water-related factors were most important for 25 of the 29 species analysed. The strong response of palm distributions to climate in combination with the importance of non-environmental spatial constraints suggests that African palms will be sensitive to future climate changes, but that their ability...

  1. [Simultaneous determination of 7 arsenic species in chicken muscle and chicken liver with high performance liquid chromatography-inductively coupled plasma mass spectrometry].

    Science.gov (United States)

    Yang, Lijun; Hu, Qiaoru; Guo, Wei; Liu, Yumin; Song, Xiaohua; Zhang, Pengcheng

    2011-05-01

    A method for the simultaneous determination of 7 arsenic species was developed with high performance liquid chromatography and inductively coupled plasma mass spectrometry (HPLC-ICP-MS). The sample was extracted with artificial gastric juice. The HPLC separation was performed on an anion analytical column utilizing a gradient elution program of ammonium carbonate and water as the mobile phase. Identification and quantification were achieved by ICP-MS. Good linearities of 7 arsenic species were observed in the range from 1 microg/kg to 50 microg/kg with the correlation coefficients greater than 0.999. The average recoveries of 7 arsenic species spiked at the three levels of 1, 2 and 10 microg/kg ranged from 84.3% to 106.6% with the relative standard deviations of 1.4%-4.2%. The quantification limits of 7 arsenic species were 1 microg/kg. The method was proved to be good reproducibility, high sensitivity and simple preprocessing. This method is suitable for the simultaneous determination of 7 arsenic species in chicken muscle and chicken liver.

  2. Rates of Water Loss and Uptake in Recalcitrant Fruits of Quercus Species Are Determined by Pericarp Anatomy

    Science.gov (United States)

    Xia, Ke; Daws, Matthew I.; Stuppy, Wolfgang; Zhou, Zhe-Kun; Pritchard, Hugh W.

    2012-01-01

    Desiccation-sensitive recalcitrant seeds and fruits are killed by the loss of even moderate quantities of water. Consequently, minimizing the rate of water loss may be an important ecological factor and evolutionary driver by reducing the risk of mortality during post-dispersal dry-spells. For recalcitrant fruits of a range of Quercus species, prolonged drying times have been observed previously. However, the underlying mechanism(s) for this variation is unknown. Using nine Quercus species we investigated the major route(s) of water flow into and out of the fruits and analysed the relative importance of the different pericarp components and their anatomy on water uptake/loss. During imbibition (rehydration), the surface area of the cupule scar and the frequency and area of the vascular bundles contained therein were significantly correlated with the rates of water uptake across the scar. The vascular bundles serving the apex of the fruit were a minor contributor to overall water. Further, the rate of water uptake across the remainder of the pericarp surface was significantly correlated with the thickness of the vascularised inner layer in the pericarp. Fruits of Q. franchetii and Q. schottkyana dried most slowly and had a comparatively small scar surface area with few vascular bundles per unit area. These species inhabit drier regions than the other species studied, suggesting these anatomical features may have ecological value by reducing the risk of desiccation stress. However, this remains to be tested in the field. PMID:23071795

  3. Comparison of extraction and transesterification methods on the determination of the fatty acid contents of three Brazilian seaweed species

    Directory of Open Access Journals (Sweden)

    Aline P. Martins

    2012-08-01

    Full Text Available Seaweeds are photosynthetic organisms important to their ecosystem and constitute a source of compounds with several different applications in the pharmaceutical, cosmetic and biotechnology industries, such as triacylglycerols, which can be converted to fatty acid methyl esters that make up biodiesel, an alternative source of fuel applied in economic important areas. This study evaluates the fatty acid profiles and concentrations of three Brazilian seaweed species, Hypnea musciformis (Wulfen J.V. Lamouroux (Rhodophya, Sargassum cymosum C. Agardh (Heterokontophyta, and Ulva lactuca L. (Chlorophyta, comparing three extraction methods (Bligh & Dyer - B&D; AOAC Official Methods - AOM; and extraction with methanol and ultrasound - EMU and two transesterification methods (7% BF3 in methanol - BF3; and 5% HCl in methanol - HCl. The fatty acid contents of the three species of seaweeds were significantly different when extracted and transesterified by the different methods. Moreover, the best method for one species was not the same for the other species. The best extraction and transesterification methods for H. musciformis, S. cymosum and U. lactuca were, respectively, AOM-HCl, B&D-BF3 and B&D-BF3/B&D-HCl. These results point to a matrix effect and the method used for the analysis of the fatty acid content of different organisms should be selected carefully.

  4. Comparison of extraction and transesterification methods on the determination of the fatty acid contents of three Brazilian seaweed species

    Directory of Open Access Journals (Sweden)

    Aline P. Martins

    2012-06-01

    Full Text Available Seaweeds are photosynthetic organisms important to their ecosystem and constitute a source of compounds with several different applications in the pharmaceutical, cosmetic and biotechnology industries, such as triacylglycerols, which can be converted to fatty acid methyl esters that make up biodiesel, an alternative source of fuel applied in economic important areas. This study evaluates the fatty acid profiles and concentrations of three Brazilian seaweed species, Hypnea musciformis (Wulfen J.V. Lamouroux (Rhodophya, Sargassum cymosum C. Agardh (Heterokontophyta, and Ulva lactuca L. (Chlorophyta, comparing three extraction methods (Bligh & Dyer - B&D; AOAC Official Methods - AOM; and extraction with methanol and ultrasound - EMU and two transesterification methods (7% BF3 in methanol - BF3; and 5% HCl in methanol - HCl. The fatty acid contents of the three species of seaweeds were significantly different when extracted and transesterified by the different methods. Moreover, the best method for one species was not the same for the other species. The best extraction and transesterification methods for H. musciformis, S. cymosum and U. lactuca were, respectively, AOM-HCl, B&D-BF3 and B&D-BF3/B&D-HCl. These results point to a matrix effect and the method used for the analysis of the fatty acid content of different organisms should be selected carefully.

  5. CCQM-K108.2014: determination of arsenic species and total arsenic in brown rice flour

    Science.gov (United States)

    Inagaki, K.; Narukawa, T.; Hioki, A.; Miyashita, S.; Long, S. E.; Ellisor, M. B.; Peng, S. L.; Dewi, F.; Shin, R.; Kapp, T.; Wai-hong, F.; Hei-shing, C.; Chao, W.; Kaewkhomdee, N.; Taebunpakul, S.; Thiengmanee, U.; Yafa, C.

    2017-01-01

    The key comparison CCQM-K108.2014 was organised by the Inorganic Analysis Working Group (IAWG) of CCQM to test the abilities of the national metrology institutes (NMIs) or the designated institutes (DIs) to measure the mass fractions of inorganic arsenic (i-As, sum of the amount of arsenite [As(III)] and arsenate [As(V)]), dimethylarsinic acid (DMAA), and total arsenic (total As) in brown rice flour. This was the follow-up comparison for the CCQM-K108 & CCQM-P147 (Cd, As, inorganic arsenic, and DMAA in brown rice flour). For total As, no strong outliers among the reported values were observed, and the distribution of the results was narrow, within 3% around the median. For i-As and DMAA, the distributions of the results were slightly wider than that for total arsenic, but no strong outliers among the reported values of i-As and DMAA were observed. Two potentially bias sources, an extraction efficiency of As species (the ratio of the sum of i-As and DMAA to total As) and the quality of primary standard of DMAA, were discussed. The extraction efficiency was estimated as the ratio of the sum of i-As and DMAA to total As. In the previous comparison (CCQM-K108 & CCQM-P147), the extraction efficiency was one of the largest bias sources for i-As and DMAA. However, in this study, all the extraction efficiencies estimated from the reported values were close to 100 %. Regarding the quality of the primary standard solutions, no significant difference was observed among the primary standard solution used by the participants. These results suggest the two potential bias sources mentioned above would not have been majors in this study, and then the technical issues in the previous comparison had been overcome. Accounting for relative expanded uncertainty, a comparability of measurement was successfully demonstrated by the participating NMIs and DIs for the measurement of total As at the level of less than 0.7 mg/kg, i-As at the level of less than 0.6 mg/kg, and DMAA at the level

  6. The Dopamine D2 Receptor Gene in Lamprey, Its Expression in the Striatum and Cellular Effects of D2 Receptor Activation

    Science.gov (United States)

    Robertson, Brita; Huerta-Ocampo, Icnelia; Ericsson, Jesper; Stephenson-Jones, Marcus; Pérez-Fernández, Juan; Bolam, J. Paul; Diaz-Heijtz, Rochellys; Grillner, Sten

    2012-01-01

    All basal ganglia subnuclei have recently been identified in lampreys, the phylogenetically oldest group of vertebrates. Furthermore, the interconnectivity of these nuclei is similar to mammals and tyrosine hydroxylase-positive (dopaminergic) fibers have been detected within the input layer, the striatum. Striatal processing is critically dependent on the interplay with the dopamine system, and we explore here whether D2 receptors are expressed in the lamprey striatum and their potential role. We have identified a cDNA encoding the dopamine D2 receptor from the lamprey brain and the deduced protein sequence showed close phylogenetic relationship with other vertebrate D2 receptors, and an almost 100% identity within the transmembrane domains containing the amino acids essential for dopamine binding. There was a strong and distinct expression of D2 receptor mRNA in a subpopulation of striatal neurons, and in the same region tyrosine hydroxylase-immunoreactive synaptic terminals were identified at the ultrastructural level. The synaptic incidence of tyrosine hydroxylase-immunoreactive boutons was highest in a region ventrolateral to the compact layer of striatal neurons, a region where most striatal dendrites arborise. Application of a D2 receptor agonist modulates striatal neurons by causing a reduced spike discharge and a diminished post-inhibitory rebound. We conclude that the D2 receptor gene had already evolved in the earliest group of vertebrates, cyclostomes, when they diverged from the main vertebrate line of evolution (560 mya), and that it is expressed in striatum where it exerts similar cellular effects to that in other vertebrates. These results together with our previous published data (Stephenson-Jones et al. 2011, 2012) further emphasize the high degree of conservation of the basal ganglia, also with regard to the indirect loop, and its role as a basic mechanism for action selection in all vertebrates. PMID:22563388

  7. Common antigenic determinants of haemoglobin as basis of immunological cross-reactivity between chironomid species (Diptera, Chironomidae): studies with human and animal sera.

    Science.gov (United States)

    Baur, X; Dewair, M; Haegele, K; Prelicz, H; Scholl, A; Tichy, H

    1983-01-01

    Chironomids, of which approximately 10,000 species exist, are reported to cause severe immediate type allergic diseases in man. In the present study, immunological cross-reactivity between 14 chironomid species from different continents was proven by RAST inhibition, double immunodiffusion and a new allergoprint technique, based upon PAGE separation of insect crude extracts. Using isolated chironomid haemoglobins and sera of sensitized persons, as well as rabbit antibodies against larval crude extract or against the haemoglobin fraction of Chironomus thummi, it could be proven that cross-reactivity derives at least predominantly from haemoglobin components with common antigenic determinants in the different species. Images Fig. 2 Fig. 7 Fig. 8 Fig. 9 PMID:6197219

  8. Determination of Fe2+ and Fe3+ species by FIA-CRC-ICP-MS in Antarctic ice samples

    DEFF Research Database (Denmark)

    Spolaor, A; Vallelonga, Paul Travis; Gabrieli, J

    2012-01-01

    contexts depends strongly on its oxidation state. Solubility in water and the capacity to form complexes are just two important characteristics that are species dependent. Distinguishing between the two iron species, Fe(II) and Fe(III), is necessary to evaluate bioavailability, as Fe(II) is more soluble...... detection limit is 0.01 ng g-1. A chelating resin, Ni-NTA Superflow, was used to separate the Fe species: At pH 2 the resin is capable of retaining Fe3+ with no retention of Fe2+. After the initial separation, we oxidized the Fe2+ using H2O2, and determined the Fe2+ concentration as the difference between...

  9. Sensitive determination of iodine species, including organo-iodine, for freshwater and seawater samples using high performance liquid chromatography and spectrophotometric detection

    International Nuclear Information System (INIS)

    Schwehr, Kathleen A.; Santschi, Peter H.

    2003-01-01

    In order to more effectively use iodine isotope ratios, 129 I/ 127 I, as hydrological and geochemical tracers in aquatic systems, a new high performance liquid chromatography (HPLC) method was developed for the determination of iodine speciation. The dissolved iodine species that dominate natural water systems are iodide, iodate, and organic iodine. Using this new method, iodide was determined directly by combining anion exchange chromatography and spectrophotometry. Iodate and the total of organic iodine species are determined as iodide, with minimal sample preparation, compared to existing methods. The method has been applied to quantitatively determine iodide, iodate as the difference of total inorganic iodide and iodide after reduction of the sample by NaHSO 3 , and organic iodine as the difference of total iodide (after organic decomposition by dehydrohalogenation and reduction by NaHSO 3 ) and total inorganic iodide. Analytical accuracy was tested: (1) against certified reference material, SRM 1549, powdered milk (NIST); (2) through the method of standard additions; and (3) by comparison to values of environmental waters measured independently by inductively coupled plasma mass spectrometry (ICP-MS). The method has been successfully applied to measure the concentrations of iodide species in rain, surface and ground water, estuarine and seawater samples. The detection limit was ∼1 nM (0.2 ppb), with less than 3% relative standard deviation (R.S.D.) for samples determined by standard additions to an iodide solution of 20 nM in 0.1 M NaCl. This technique is one of the few methods sensitive enough to accurately quantify stable iodine species at nanomolar concentrations in aquatic systems across a range of matrices, and to quantitatively measure organic iodine. Additionally, this method makes use of a very dilute mobile phase, and may be applied to small sample volumes without pre-column concentration or post-column reactions

  10. Determination of the species specificity of the primers for the detection of chicken and turkey meat by realtime PCR method

    Directory of Open Access Journals (Sweden)

    Lenka Maršálková

    2014-07-01

    Full Text Available The aim of this work was to use TaqMan Real-Time PCR for quantitative authentication of chicken and turkey meat. To meet this purpose, a specific pair of primers and TaqMan probe was used. The test was aimed at identifying the reaction cycle of turkey and chicken meat using by two sets of primers. With first set of primer designed for chicken we obtained the following results: Cp = 16.18 for 100% chicken DNA Cp = 29, 18 100% turkey DNA It was also amplified DNA of pig that exceeded the detection threshold fluorescence intensities in the 31.07 cycle (Cp = 31.07. Using primers designed for turkey we obtained the following results Cp = 31.16 for 100% CHDNA, Cp =16.18 100% TDNA. It was also amplified the 100% DNA of rabbit in 31.63 cycle (Cp = 31.63 and deer in cycle 32 (Cp = 32. The DNA of all other animal species was amplificated after more than 35 cycles (Cp >35. It follows that the second detection primer pair is specific enough to unrelated species of animals by 30 cycles of the reaction. Species authentication based on DNA analysis from this perspective overcomes all the shortcomings of proteins. At present, DNA analysis use different types of PCR. Is the most progressive Real-time PCR, which is suitable for the specific use of detection (primers and TaqMan probe. The TaqMan Real-time PCR is within the sensitivity and specificity, clearly one of the best methods for identifying the species of chicken and turkey meat. The specificity of this method, however, depends primarily on the specificity of the primers and TaqMan probe. The 30 cycle reaction was chosen by us as the threshold for specificity using primers for authentication chicken and turkey meat.

  11. Development and application of a sampling method for the determination of reactive halogen species in volcanic gas emissions

    Science.gov (United States)

    Rüdiger, Julian; Bobrowski, Nicole; Liotta, Marcello; Hoffmann, Thorsten

    2017-04-01

    Volcanoes are a potential large source of several reactive atmospheric trace gases including sulfur and halogen containing species. Besides the importance for atmospheric chemistry, the detailed knowledge of halogen chemistry in volcanic plumes can help to get insights into subsurface processes. In this study a gas diffusion denuder sampling method, using a 1,3,5-trimethoxybenzene (1,3,5-TMB) coating for the derivatization of reactive halogen species (RHS), was characterized by dilution chamber experiments. The coating proved to be suitable to collect selectively gaseous bromine species with oxidation states (OS) of +1 or 0 (such as Br2, BrCl, BrO(H) and BrONO2), while being ignorant to HBr (OS -1). The reaction of 1,3,5-TMB with reactive bromine species gives 1-bromo-2,4,6-trimethoxybenzene (1-bromo-2,4,6-TMB) - other halogens give corresponding products. Solvent elution of the derivatized analytes and subsequent analysis with gas chromatography mass spectrometry gives detection limits of 10 ng or less for Br2, Cl2, and I2. In 2015 the method was applied on volcanic gas plumes at Mt. Etna (Italy) giving reactive bromine mixing ratios from 0.8 ppbv to 7.0 ppbv. Total bromine mixing ratios of 4.7 ppbv to 27.5 ppbv were obtained by simultaneous alkaline trap sampling (by a Raschig-tube) followed by analysis with ion chromatography and inductively coupled plasma mass spectrometry. This leads to the first results of in-situ measured reactive bromine to total bromine ratios, spanning a range between 12±1 % and 36±2 %. Our finding is in an agreement with previous model studies, which imply values < 44 % for plume ages < 1 minute, which is consistent with the assumed plume age at the sampling sites.

  12. Differential exudation of two benzoxazinoids--one of the determining factors for seedling allelopathy of Triticeae species.

    Science.gov (United States)

    Belz, Regina G; Hurle, Karl

    2005-01-26

    Benzoxazinoids (Bx) are natural phytotoxins that function as chemical defense compounds in several species. The release of Bx by intact plant roots associated these compounds with root allelopathy in Triticeae species; however, the significance of exudate concentrations of Bx for plant-plant interactions is still a controversial question. A biological screening of 146 cultivars of four Triticeae species (Triticum aestivum L., Triticum durum Desf., Triticum spelta L., and Secale cereale L.) demonstrated a high cultivar dependence to suppress the root growth of Sinapis alba L. by root allelopathy in a dose-response bioassay. Only a few cultivars possessed a marked high or low allelopathic activity, whereby high-performance liquid chromatography-diode array detection analysis of root exudates revealed that these cultivars differed considerably in their ability to exude the two Bx aglucones, DIBOA [2,4-dihydroxy-2H-1,4-benzoxazin-3(4H)-one] and DIMBOA [2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one]. The total amount of DIBOA and DIMBOA exuded showed a significant correlation to the growth inhibition in bioassay with a statistically estimated contribution to the overall allelopathic effect of 48-72%. In a bioassay with pure phytotoxins, Bx concentrations consistent with the amounts quantified in the screening bioassay caused detrimental effects on S. alba and almost reproduced the statistically estimated contribution. The observed causal association between the allelopathic activity under laboratory conditions and the exudate concentrations of Bx suggests that this association might have implications for the interference of Triticeae species in natural plant communities.

  13. Isotopic determination of the trophic ecology of a ubiquitous key species - The crab Liocarcinus depurator (Brachyura: Portunidae)

    Science.gov (United States)

    Careddu, Giulio; Calizza, Edoardo; Costantini, Maria Letizia; Rossi, Loreto

    2017-05-01

    Knowledge of the trophic ecology of predators is key to understanding how they affect food web structure and ecosystem functioning. The harbour crab Liocarcinus depurator (L.) (Brachyura: Portunidae) is one of the most abundant decapod species in soft-bottom areas of the Mediterranean Sea and northeast Atlantic Ocean. It is both a common prey and predator of commercial and non-commercial marine species and its predation pressure appears to have little effect on the subtidal community assemblage. However, there are few studies of its diet and little is known about its role in mediating energy flows in marine ecosystems. In this study, carbon (δ13C) and nitrogen (δ15N) stable isotope analysis (SIA) and Bayesian analytical tools were used to characterise the trophic niche of L. depurator and to quantify the most important prey supporting this species under various environmental conditions. Specimens of L. depurator, their potential prey and basal resources were collected from two different subtidal areas of the Gulf of Gaeta, one affected by human activities (north side) and the other seasonally influenced by freshwater inputs originating from the River Garigliano (south side). While there were differences between the two sampling areas in terms of the abundance and δ15N and δ13C values of the macrobenthic prey community, no differences in the δ15N values and trophic position of L. depurator were observed. Specifically, Bayesian mixing models showed Polychaeta Errantia as the main source of crab diets in both areas. The observed differences in the δ13C values and the analysis of trophic pathways also indicate that the terrestrial organic matter originating from the discharge of the River Garigliano was integrated along the food web up to L. depurator. Although this species is usually considered an opportunistic feeder, it appears to be highly selective and its trophic habits did not influence food web topology, which in contrast was found to be strongly

  14. Ecomorphology of the African felid ensemble: the role of the skull and postcranium in determining species segregation and assembling history.

    Science.gov (United States)

    Morales, M M; Giannini, N P

    2013-05-01

    Morphology of extant felids is regarded as highly conservative. Most previous studies have focussed on skull morphology, so a vacuum exists about morphofunctional variation in postcranium and its role in structuring ensembles of felids in different continents. The African felid ensemble is particularly rich in ecologically specialized felids. We studied the ecomorphology of this ensemble using 31 cranial and 93 postcranial morphometric variables measured in 49 specimens of all 10 African species. We took a multivariate approach controlling for phylogeny, with and without body size correction. Postcranial and skull + postcranial analyses (but not skull-only analyses) allowed for a complete segregation of species in morphospace. Morphofunctional factors segregating species included body size, bite force, zeugopodial lengths and osteological features related to parasagittal leg movement. A general gradient of bodily proportions was recovered: lightly built, long-legged felids with small heads and weak bite forces vs. the opposite. Three loose groups were recognized: small terrestrial felids, mid-to-large sized scansorial felids and specialized Acinonyx jubatus and Leptailurus serval. As predicted from a previous study, the assembling of the African felid ensemble during the Plio-Pleistocene occurred by the arrival of distinct felid lineages that occupied then vacant areas of morphospace, later diversifying in the continent. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  15. The role of temperature in determining species' vulnerability to ocean acidification: a case study using Mytilus galloprovincialis.

    Directory of Open Access Journals (Sweden)

    Kristy J Kroeker

    Full Text Available Ocean acidification (OA is occurring across a backdrop of concurrent environmental changes that may in turn influence species' responses to OA. Temperature affects many fundamental biological processes and governs key reactions in the seawater carbonate system. It therefore has the potential to offset or exacerbate the effects of OA. While initial studies have examined the combined impacts of warming and OA for a narrow range of climate change scenarios, our mechanistic understanding of the interactive effects of temperature and OA remains limited. Here, we use the blue mussel, Mytilus galloprovincialis, as a model species to test how OA affects the growth of a calcifying invertebrate across a wide range of temperatures encompassing their thermal optimum. Mussels were exposed in the laboratory to a factorial combination of low and high pCO2 (400 and 1200 µatm CO2 and temperatures (12, 14, 16, 18, 20, and 24°C for one month. Results indicate that the effects of OA on shell growth are highly dependent on temperature. Although high CO2 significantly reduced mussel growth at 14°C, this effect gradually lessened with successive warming to 20°C, illustrating how moderate warming can mediate the effects of OA through temperature's effects on both physiology and seawater geochemistry. Furthermore, the mussels grew thicker shells in warmer conditions independent of CO2 treatment. Together, these results highlight the importanc