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Sample records for submersed monocot hydrilla

  1. Keystone Functions of Hydrilla verticillata

    Indian Academy of Sciences (India)

    IAS Admin

    to drought, but largely due to the loss of aquatic vegetation, particularly Hydrilla verticillata ... Hydrilla for aeration, or through migrant water birds to whose feathers and feet the ... biological control of this weed [6]. This is a case of beneficial.

  2. Chironomidae (Insecta: Diptera) Collected from Hydrilla Verticillata ...

    African Journals Online (AJOL)

    A survey of the aquatic weed Hydrilla verticillata was conducted in selected Kenyan and Ugandan lakes, and emerging chironomid adults were collected from samples of Hydrilla and seven other aquatic macrophytes. Hydrilla was absent from Lake Victoria, in sites where it previously occurred. Hydrilla was found in four of ...

  3. The Ecology and Environmental Impacts of Hydrilla

    Science.gov (United States)

    1992-10-15

    in the dewatered areas. The drawdown also encouraged the germination of waterhyacinth seeds in the dewatered areas. Plant Analysis The productivity of...controls hydrilla in most situations. Sonar is the DowElanco registered trademark for products containing the active ingredient fluridone . Sonar aquatic

  4. Integrated Weed Management Strategies for Control of Hydrilla

    National Research Council Canada - National Science Library

    Nelson, Linda S; Shearer, Judy F

    2009-01-01

    ...), and the fungal pathogen Mycoleptodiscus terrestris (Gerd.) Ostazeski, applied alone and in combination with one another, as an integrated weed management strategy against the nuisance aquatic plant, hydrilla...

  5. Submersion and acute respiratory failure

    Directory of Open Access Journals (Sweden)

    Yu-Jang Su

    2014-01-01

    Conclusions: Submersion patients who are hypothermic on arrival of emergency department (ED are risky to respiratory failure and older, more hypothermic, longer hospital stay in suicidal submersion patients.

  6. Interspecific competition effects on phosphorus accumulation by Hydrilla verticillata and Vallisneria natans.

    Science.gov (United States)

    Zhang, Xiufeng; Liu, Zhengwen

    2011-01-01

    The competition between submersed plants has been recognized as an important factor influencing the structure of plant communities in shallow lakes. The ability of different species to take up and store nutrients from the surrounding ambience varies, and hence plant community structure might be expected to affect the cycling of nutrients in lake ecosystems. In this study, the uptake of phosphorus by Hydrilla verticillata and Vallisneria natans was studied and compared in monoculture and competitive mixed-culture plantings. Results showed that for both studied species the phosphorus concentrations of different tissues and of whole plants was unaffected by competition. However, the quantity of phosphorus accumulated by whole plants of H. verticillata was significantly higher in mixture culture than in monoculture, while that of V. natans was lower in the mixed culture. The results indicated that H. verticillata has a competitive advantage over V. natans, when the two species are grown in competition, and is able to accumulate a greater quantity of phosphorus.

  7. Genome Size Dynamics and Evolution in Monocots

    Directory of Open Access Journals (Sweden)

    Ilia J. Leitch

    2010-01-01

    Full Text Available Monocot genomic diversity includes striking variation at many levels. This paper compares various genomic characters (e.g., range of chromosome numbers and ploidy levels, occurrence of endopolyploidy, GC content, chromosome packaging and organization, genome size between monocots and the remaining angiosperms to discern just how distinctive monocot genomes are. One of the most notable features of monocots is their wide range and diversity of genome sizes, including the species with the largest genome so far reported in plants. This genomic character is analysed in greater detail, within a phylogenetic context. By surveying available genome size and chromosome data it is apparent that different monocot orders follow distinctive modes of genome size and chromosome evolution. Further insights into genome size-evolution and dynamics were obtained using statistical modelling approaches to reconstruct the ancestral genome size at key nodes across the monocot phylogenetic tree. Such approaches reveal that while the ancestral genome size of all monocots was small (1C=1.9 pg, there have been several major increases and decreases during monocot evolution. In addition, notable increases in the rates of genome size-evolution were found in Asparagales and Poales compared with other monocot lineages.

  8. Surveys for Pathogens of Monoecious Hydrilla

    Science.gov (United States)

    2014-01-01

    California ( Madeira et al. 2004). Monoecious hydrilla was first discovered in Delaware in 1976 and later in the Potomac River (Haller 1982, Steward et al...1984). It has now expanded its distribution through the Atlantic States and northward to Maine ( Madeira et al. 2004). Separate populations have...the water surface and then spreading laterally and forming a mat (Van 1989). Madeira et al. (1997) hypothesized that this growth form was an

  9. Surveys for Pathogens of Monoecious Hydrilla 2014

    Science.gov (United States)

    2016-06-01

    has given it new status as an invasive species of great concern. Monoecious hydrilla management is primarily through chemical control using endothall...result in removal of non-target species , an outcome that might be highly undesirable in native aquatic plant restoration efforts. While the ephydrid...and Wisconsin have also been eradicated1. The most recent invasions have appeared in Lake Cayuga, the Erie Canal at North Tonawanda, upstate New

  10. Genetic Relationships among Invasive Hydrilla (Hydrilla verticillata L.f. Royle) Biotypes in the US and Their Implications for Management

    Science.gov (United States)

    2014-02-01

    throughout this large distribution, although they may be due to environmentally induced plasticity , rather than being indicative of taxonomic...Surveys of hydrilla herbivores have been undertaken in India, Pakistan, Malaysia , Korea, Japan, Thailand, Vietnam, Africa, and Australia (Bennett and... Malaysia (Steward 1993). US monoecious hydrilla plants likely originated in Korea (Madeira et al. 2007, Benoit 2011); therefore, natural enemy

  11. Exploration for Natural Enemies of Hydrilla verticillata in Eastern Africa.

    Science.gov (United States)

    1980-05-01

    mandibles and heads than the scavengers. Bill Beck of Florida A&M University, who identified the hydrilla midge as a species of Polypedilum, feels...that the head and mandibles of this midge resemble those of the scavenger section instead of the herbivore section of the genus, as the types occur in...Lakshmanan, K. K. 1965. " Embryological Studies in the Hydrocharitaceae. IV. Post-Fertilization Development in Hydrilla verticillata Royle," Phyton Rev

  12. TIR-NBS-LRR genes are rare in monocots: evidence from diverse monocot orders

    Directory of Open Access Journals (Sweden)

    Tarr D Ellen K

    2009-09-01

    Full Text Available Abstract Background Plant resistance (R gene products recognize pathogen effector molecules. Many R genes code for proteins containing nucleotide binding site (NBS and C-terminal leucine-rich repeat (LRR domains. NBS-LRR proteins can be divided into two groups, TIR-NBS-LRR and non-TIR-NBS-LRR, based on the structure of the N-terminal domain. Although both classes are clearly present in gymnosperms and eudicots, only non-TIR sequences have been found consistently in monocots. Since most studies in monocots have been limited to agriculturally important grasses, it is difficult to draw conclusions. The purpose of our study was to look for evidence of these sequences in additional monocot orders. Findings Using degenerate PCR, we amplified NBS sequences from four monocot species (C. blanda, D. marginata, S. trifasciata, and Spathiphyllum sp., a gymnosperm (C. revoluta and a eudicot (C. canephora. We successfully amplified TIR-NBS-LRR sequences from dicot and gymnosperm DNA, but not from monocot DNA. Using databases, we obtained NBS sequences from additional monocots, magnoliids and basal angiosperms. TIR-type sequences were not present in monocot or magnoliid sequences, but were present in the basal angiosperms. Phylogenetic analysis supported a single TIR clade and multiple non-TIR clades. Conclusion We were unable to find monocot TIR-NBS-LRR sequences by PCR amplification or database searches. In contrast to previous studies, our results represent five monocot orders (Poales, Zingiberales, Arecales, Asparagales, and Alismatales. Our results establish the presence of TIR-NBS-LRR sequences in basal angiosperms and suggest that although these sequences were present in early land plants, they have been reduced significantly in monocots and magnoliids.

  13. Axial vessel widening in arborescent monocots.

    Science.gov (United States)

    Petit, Giai; DeClerck, Fabrice A J; Carrer, Marco; Anfodillo, Tommaso

    2014-02-01

    Dicotyledons have evolved a strategy to compensate for the increase in hydraulic resistance to water transport with height growth by widening xylem conduits downwards. In monocots, the accumulation of hydraulic resistance with height should be similar, but the absence of secondary growth represents a strong limitation for the maintenance of xylem hydraulic efficiency during ontogeny. The hydraulic architecture of monocots has been studied but it is unclear how monocots arrange their axial vascular structure during ontogeny to compensate for increases in height. We measured the vessel lumina and estimated the hydraulic diameter (Dh) at different heights along the stem of two arborescent monocots, Bactris gasipaes (Kunth) and Guadua angustifolia (Kunth). For the former, we also estimated the variation in Dh along the leaf rachis. Hydraulic diameter increased basally from the stem apex to the base with a scaling exponent (b) in the range of those reported for dicot trees (b = 0.22 in B. gasipaes; b = 0.31 and 0.23 in G. angustifolia). In B. gasipaes, vessels decrease in Dh from the stem's centre towards the periphery, an opposite pattern compared with dicot trees. Along the leaf rachis, a pattern of increasing Dh basally was also found (b = 0.13). The hydraulic design of the monocots studied revealed an axial pattern of xylem conduits similar to those evolved by dicots to compensate and minimize the negative effect of root-to-leaf length on hydrodynamic resistance to water flow.

  14. Submersible energy storage apparatus

    International Nuclear Information System (INIS)

    Mccartney, J.F.; Rowe, R.A.

    1980-01-01

    A submersible energy storage apparatus for an electrical power source is provided which includes an electrolysis unit feed water gas collection assembly and a fuel cell. The electrolysis unit feed water gas collection assembly includes a hydrogen container and an oxygen container wherein each container has a gas outlet and is capable of containing feed water as well as hydrogen and oxygen gases respectively. An electrolysis cell is provided which has a hydrogen outlet, an oxygen outlet and a feed water inlet. The hydrogen outlet is located in the hydrogen container, the oxygen outlet is located in the oxygen container, and the feed water inlet is located in one of the containers. Each of the containers has an opening to the submersible environment so as to be pressure responsive thereto. A barrier device is provided in association with the opening in each container for isolating the feed water in the container from water in the submersible environment. The fuel cell is operatively connected to the hydrogen and oxygen containers, and the electrical power source is operatively connected to the electrolysis cell. With this arrangement the electrolysis cell is capable of utilizing power from the power source during low electrical energy demand, and the fuel cell is capable of utilizing the hydrogen and oxygen gases for generating electricity during high demand periods

  15. Overseas Surveys (1981-1983) for Insects to Control Hydrilla.

    Science.gov (United States)

    1985-12-01

    various aquatic habitats, but no hydrilla was found. Because of the Hari Raya holidays, most hotels were booked and almost a quarter of the total of 1,400...assistant. Mr. Ho spent most of morn- ing telephoning people in Malaysian Agriculture and Irrigation Departments. Because of holidays (Harl Raya ) that

  16. Establishing Research and Management Priorities for Monoecious Hydrilla

    Science.gov (United States)

    2014-01-01

    this definition. Monoecious hydrilla is considered highly invasive in large reservoirs of the Mid- Atlantic states; however, widespread use of grass...drawdowns or fluctuations in water levels, high spring flows, and early spring turbidity (i.e. disturbance) as the dormant tuber bank is largely... West Virginia, Ohio, and Kentucky) are of particular concern, as these infestations may be a source of new and continuing introductions into

  17. Phytofabrication of silver nanoparticles by using aquatic plant Hydrilla verticilata

    Directory of Open Access Journals (Sweden)

    MAHENDRA RAI

    2012-07-01

    Full Text Available Sable N, Gaikwad S, Bonde S, Gade A, Rai M. 2012. Phytofabrication of silver nanoparticles by using aquatic plant Hydrilla verticilata. Nusantara Bioscience 4: 45-49. In the context of current drive to developed new green technology in nanomaterials, synthesis of nanoparticles is of considerable importance. There has been considerable work done in the field of nanoscience and nanotechnology during the last decade due to the introduction of various protocols for the synthesis of nanoparticles by using plants and microorganisms. Here we firstly report the extracellular phytosynthesis of silver nanoparticles (Ag-NPs using aquatic plants Hydrilla verticilata. The characterization of the phytosynthesized Ag-NPs was done with the help of UV-Vis spectroscopy, FTIR, Nanoparticle Tracking Analysis (NTA, Zeta potential and SEM. The SEM micrograph revealed the synthesis of polydispersed spherical nanoparticles, with the average size of 65.55 nm. The phytofabricated Ag-NPs can be used in the field of medicine and agriculture, due to their antimicrobial potential.

  18. The distribution of submersed aquatic vegetation and water lettuce in the fresh and oligohaline tidal Potomac River, 2007

    Science.gov (United States)

    Campbell, Sarah Hunter; Rybicki, Nancy B.; Schenk, Edward R.

    2015-01-01

    Surveys documenting the composition of species of submersed aquatic vegetation (SAV) have been conducted in the Potomac River for decades. These surveys can help managers assess the proportion of native and exotic plants in the river or can be used to determine relationships between native and exotic plants, environmental conditions, and wildlife. SAV coverage increased from 2005 to 2007 throughout the fresh and oligohaline study area. The 2007 survey documented here determined that eleven species of SAV were present. The abundance of the exotic species Hydrilla verticillata (hydrilla) was relatively low, and species diversity was relatively high compared to previous years. The survey also revealed a new population of the invasive, floating aquatic plant Pistia stratiotes (water lettuce). In 2007, water lettuce, the latest exotic aquatic plant to be found in the fresh to oligohaline portion of the Potomac River, was most abundant in Mattawoman Creek, Charles County, Maryland. However, it was not observed in the fresh to oligohaline portion of the Potomac River in the summer of 2008. An understanding of the distribution of SAV species and factors governing the abundance of native and invasive aquatic species is enhanced by long-term surveys.

  19. Submersible Generator for Marine Hydrokinetics

    Energy Technology Data Exchange (ETDEWEB)

    Cinq-Mars, Robert S; Burke, Timothy; Irish, James; Gustafson, Brian; Kirtley, James; Alawa, Aiman

    2011-09-01

    A submersible generator was designed as a distinct and critical subassembly of marine hydrokinetics systems, specifically tidal and stream energy conversion. The generator is designed to work with both vertical and horizontal axis turbines. The final product is a high-pole-count, radial-flux, permanent magnet, rim mounted generator, initially rated at twenty kilowatts in a two-meter-per-second flow, and designed to leverage established and simple manufacturing processes. The generator was designed to work with a 3 meter by 7 meter Gorlov Helical Turbine or a marine hydrokinetic version of the FloDesign wind turbine. The team consisted of experienced motor/generator design engineers with cooperation from major US component suppliers (magnetics, coil winding and electrical steel laminations). Support for this effort was provided by Lucid Energy Technologies and FloDesign, Inc. The following tasks were completed: Identified the conditions and requirements for MHK generators. Defined a methodology for sizing and rating MHK systems. Selected an MHK generator topology and form factor. Completed electromechanical design of submersible generator capable of coupling to multiple turbine styles. Investigated MHK generator manufacturing requirements. Reviewed cost implications and financial viability. Completed final reporting and deliverables

  20. Molecular basis of development in petaloid monocot flowers

    DEFF Research Database (Denmark)

    Johansen, Bo; Frederiksen, Signe; Skipper, Martin

    2006-01-01

    -class genes apparently are expressed in meristems of both flower and inflorescence. Morphologically petaloid stamens and styles are well known within the petaloid monocots, whereas the phenomenon is rare in core eudicots. A simple model based on the extra copies of B-class genes can explain the molecular...

  1. Experimental feeding of Hydrilla verticillata colonized by stigonematales cyanobacteria induces vacuolar myelinopathy in painted turtles (Chrysemys picta.

    Directory of Open Access Journals (Sweden)

    Albert D Mercurio

    Full Text Available Vacuolar myelinopathy (VM is a neurologic disease primarily found in birds that occurs when wildlife ingest submerged aquatic vegetation colonized by an uncharacterized toxin-producing cyanobacterium (hereafter "UCB" for "uncharacterized cyanobacterium". Turtles are among the closest extant relatives of birds and many species directly and/or indirectly consume aquatic vegetation. However, it is unknown whether turtles can develop VM. We conducted a feeding trial to determine whether painted turtles (Chrysemys picta would develop VM after feeding on Hydrilla (Hydrilla verticillata, colonized by the UCB (Hydrilla is the most common "host" of UCB. We hypothesized turtles fed Hydrilla colonized by the UCB would exhibit neurologic impairment and vacuolation of nervous tissues, whereas turtles fed Hydrilla free of the UCB would not. The ability of Hydrilla colonized by the UCB to cause VM (hereafter, "toxicity" was verified by feeding it to domestic chickens (Gallus gallus domesticus or necropsy of field collected American coots (Fulica americana captured at the site of Hydrilla collections. We randomly assigned ten wild-caught turtles into toxic or non-toxic Hydrilla feeding groups and delivered the diets for up to 97 days. Between days 82 and 89, all turtles fed toxic Hydrilla displayed physical and/or neurologic impairment. Histologic examination of the brain and spinal cord revealed vacuolations in all treatment turtles. None of the control turtles exhibited neurologic impairment or had detectable brain or spinal cord vacuolations. This is the first evidence that freshwater turtles can become neurologically impaired and develop vacuolations after consuming toxic Hydrilla colonized with the UCB. The southeastern United States, where outbreaks of VM occur regularly and where vegetation colonized by the UCB is common, is also a global hotspot of freshwater turtle diversity. Our results suggest that further investigations into the effect of the

  2. The Submersible Threat to Maritime Homeland Security

    Science.gov (United States)

    2013-09-01

    successfully utilized both semi-submersible and fully-submersible vessels during naval engagements. David boats were cigar -shaped, steam driven, wooden vessels...Capabilities: Maximum diving depth of 40 feet. Features an Auto-Hover system, built-in SONAR, Fly-By-Wire Joystick, Electronic Buoyancy Control...Features include a Fly-By-Wire Joystick, Electronic Buoyancy Control, and Electrical Systems Monitor. Cost: $ 59,000 (USD) (International VentureCraft Corp

  3. Field Surveys to Identify Biocontrol Agents of Hydrilla verticillata from June - September 2012

    Science.gov (United States)

    2015-07-01

    taxonomists for full identification. Chironomid larvae damaging tips and emerging adults were collected from hydrilla at Chetian Town, Lizui Town, and...R. S. Arias, B. E. Scheffler, S. O. Duke, M. Netherland, F. E. Dayan. 2004. Somatic mutation-mediated evolution of herbicide resistance in the

  4. Biological Control Agents of Hydrilla Verticillata; Final Report on Surveys in East Africa, 1981-1984.

    Science.gov (United States)

    1986-07-01

    vast numbers of chironomid larvae, together with small nematodes , trichopterans, and various other less abundant insect larvae. However, most of these...Luond, R. 1982. "A Revision of the Genus Hydrilla (Hydrocharitaceae)," Aquatic Botany, Vol 13, pp 485-504. Markham, R. H. 1982. "Search for Biocontrol

  5. Molecular techniques to distinguish morphologically similar Hydrilla verticillata, Egeria densa, Elodea nuttallii, and Elodea canadensis

    Science.gov (United States)

    Rybicki, Nancy B.; Kirshtein, Julie D.; Voytek, Mary A.

    2013-01-01

    The four submerged aquatic species, hydrilla (Hydrilla verticillata [monoecious and dioecious]), Brazilian waterweed (Egeria densa), Canadian waterweed (Elodea canadensis), and western waterweed (Elodea nuttallii), are difficult to positively identify because of their morphological similarity to each other, resulting in possible misidentification. This limits our ability to understand their past and present distribution, which is important in aquatic plant management. We investigated a molecular technique to identify these species, which are problematic because of their invasive nature on multiple continents. Approximately 100 samples of these species, ranging in age from 40-yr-old herbarium samples to recently collected plants, were collected from regions across the United States. The distribution and range of the samples collected in this research were compared to those reported in the literature. We confirmed information on the current wide distribution of both hydrilla biotypes in the United States and discovered that hydrilla had actually invaded the waterways near Washington, DC 6 yr earlier than originally reported. In addition, we found evidence of the confusion, dating back to the 1980s, between Canadian waterweed and western waterweed in the mid-Atlantic region of the United States. Canadian waterweed was previously reported as common and western waterweed as rare; however, our samples indicate the opposite is true. This information indicates there is a need for investigators to anticipate the spread of hydrilla populations to northern U.S. waterways, where it will compete with existing plant species, including Canadian and western waterweeds. Our ability to confirm distribution and pace of spread of invasive and noninvasive species will improve with increased application of molecular techniques.

  6. Assessment of Nelumbo nucifera and Hydrilla verticillata in the treatment of pharmaceutical industry effluent from 24 Parganas, West Bengal

    Directory of Open Access Journals (Sweden)

    Shamba Chatterjee

    2014-10-01

    Full Text Available Modern day technologies employed in industrialization and unhygienic lifestyle of mankind has led to a severe environmental menace resulting in pollution of freshwater bodies. Pharmaceutical industry effluents cause eutrophication and provide adequate nutrients for growth of pathogenic bacteria. This study has been conducted with aquatic plants water lotus (Nelumbo nucifera and hydrilla (Hydrilla verticillata with an novel aim to treat pharmaceutical industry effluents showing the outcome of the experiments carried out with the effluents collected from rural areas of 24 Parganas, West Bengal, India. Determination of pH, solid suspend, BOD5, NH3-N, MPN and coliform test were used for this notioned purpose. Pharmaceutical waste effluent water treated with water lotus showed less pH, solid suspend, DO, BOD, NH3-N, MPN and coliform bacteria than hydrilla treatment when compared to the control. In conclusion, water lotus is found to be more efficient in treatment of pharmaceutical industry effluent waste water than hydrilla.

  7. Carbon-Flow-Based Modeling of Ecophysiological Processes and Biomass Dynamics of Submersed Aquatic Plants

    National Research Council Canada - National Science Library

    Best, Elly P. H; Boyd, William A

    2007-01-01

    ...], Potamogeton pectinatus [POTAM], Hydrilla verticillata [HYDRIL], and Myriophyllum spicatum [MILFO]. These plant species are similar in growth strategy but differ significantly in morphology and physiology...

  8. Complete chloroplast genome sequence of Elodea canadensis and comparative analyses with other monocot plastid genomes.

    Science.gov (United States)

    Huotari, Tea; Korpelainen, Helena

    2012-10-15

    Elodea canadensis is an aquatic angiosperm native to North America. It has attracted great attention due to its invasive nature when transported to new areas in its non-native range. We have determined the complete nucleotide sequence of the chloroplast (cp) genome of Elodea. Taxonomically Elodea is a basal monocot, and only few monocot cp genomes representing early lineages of monocots have been sequenced so far. The genome is a circular double-stranded DNA molecule 156,700 bp in length, and has a typical structure with large (LSC 86,194 bp) and small (SSC 17,810 bp) single-copy regions separated by a pair of inverted repeats (IRs 26,348 bp each). The Elodea cp genome contains 113 unique genes and 16 duplicated genes in the IR regions. A comparative analysis showed that the gene order and organization of the Elodea cp genome is almost identical to that of Amborella trichopoda, a basal angiosperm. The structure of IRs in Elodea is unique among monocot species with the whole cp genome sequenced. In Elodea and another monocot Lemna minor the borders between IRs and LSC are located upstream of rps 19 gene and downstream of trnH-GUG gene, while in most monocots, IR has extended to include both trnH and rps 19 genes. A phylogenetic analysis conducted using Bayesian method, based on the DNA sequences of 81 chloroplast genes from 17 monocot taxa provided support for the placement of Elodea together with Lemna as a basal monocot and the next diverging lineage of monocots after Acorales. In comparison with other monocots, the Elodea cp genome has gone through only few rearrangements or gene losses. IR of Elodea has a unique structure among the monocot species studied so far as its structure is similar to that of a basal angiosperm Amborella. This result together with phylogenetic analyses supports the placement of Elodea as a basal monocot to the next diverging lineage of monocots after Acorales. So far, only few cp genomes representing early lineages of monocots have been

  9. Biomechanics and functional morphology of a climbing monocot

    Science.gov (United States)

    Hesse, Linnea; Wagner, Sarah T.; Neinhuis, Christoph

    2016-01-01

    Plants with a climbing growth habit possess unique biomechanical properties arising from adaptations to changing loading conditions connected with close attachment to mechanical supports. In monocot climbers, mechanical adaptation is restricted by the absence of a bifacial vascular cambium. Flagellaria indica was used to investigate the mechanical properties and adaptations of a monocot climber that, uniquely, attaches to the surrounding vegetation via leaf tendrils. Biomechanical methods such as three-point bending and torsion tests were used together with anatomical studies on tissue development, modification and distribution. In general, the torsional modulus was lower than the bending modulus; hence, torsional stiffness was less than flexural stiffness. Basal parts of mature stems showed the greatest stiffness while that of more apical stem segments levelled off. Mechanical properties were modulated via tissue maturation processes mainly affecting the peripheral region of the stem. Peripheral vascular bundles showed a reduction in the amount of conducting tissue while the proportion and density of the bundle sheath increased. Furthermore, adjacent bundle sheaths merged resulting in a dense ring of fibrous tissue. Although F. indica lacks secondary cambial growth, the climbing habit is facilitated by a complex interaction of tissue maturation and attachment. PMID:26819259

  10. Study on installation of the submersible mixer

    International Nuclear Information System (INIS)

    Tian, F; Shi, W D; He, X H; Xu, Y H; Jiang, H

    2013-01-01

    Study on installation of the submersible mixer for sewage treatment has been limited. In this article, large-scale computational fluid dynamics software FLUENT6.3 was adopted. ICEM software was used to build an unstructured grid of sewage treatment pool. After that, the sewage treatment pool was numerically simulated by dynamic coordinate system technology and RNG k-ε turbulent model and PIOS algorithm. Agitation pools on four different installation location cases were simulated respectively, and the external characteristic of the submersible mixer and the velocity cloud of the axial section were respectively comparatively analyzed. The best stirring effect can be reached by the installation location of case C, which is near the bottom of the pool 600 mm and blade distance the bottom at least for 200 mm wide and wide edge and narrow edge distance by 4:3. The conclusion can guide the engineering practice

  11. Development of submersible axial pump for wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Jeong Eui [Kangwon Nat' l Univ., Chuncheon (Korea, Republic of)

    2013-02-15

    This study was performed to develop a high efficiency submersible axial pump for concentration wastewater treatment. To do this, we simulated the effect of some parameters such as the axial twist angle of a blade({beta}), the radial twist angle of a blade({alpha}) and the length of a blade ({iota}) on pump efficiency using commercial code, ANSYS CFX and BladeGen. The results showed that the axial twist angle of a blade({beta}) was the most sensible parameter on the pump efficiency. And the pump efficiency had a maximum at {beta}=20.deg, {alpha}=110.deg and {iota}=240mm.

  12. Cooling devices and methods for use with electric submersible pumps

    Science.gov (United States)

    Jankowski, Todd A; Hill, Dallas D

    2014-12-02

    Cooling devices for use with electric submersible pump motors include a refrigerator attached to the end of the electric submersible pump motor with the evaporator heat exchanger accepting all or a portion of the heat load from the motor. The cooling device can be a self-contained bolt-on unit, so that minimal design changes to existing motors are required.

  13. Culture Methodology for Experimental Investigations Involving Rooted Submersed Aquatic Plants.

    Science.gov (United States)

    1984-11-01

    stolons or runners are best planted as intact plants (Sculthorpe 1967). Many species can be propagated from seed in addition to the above methods...J. 1984. Growth response of Myriophyllwm spicatu and Hydrilla verticillata when exposed to continuous, low concentrations of fluridone . Tech. Rept. A...aquatic plants, water, and bottom sediments. Weed Sci. 20:482-486. Sastroutomo, S. S. 1980. Dormancy and germination in axillary turions of iijiilZla

  14. A submersible physics laboratory experiment. Technical report

    International Nuclear Information System (INIS)

    Stehling, K.R.

    1979-01-01

    Since 1972, NOAA (OOE and MUSandT) and the University of Washington Physics Department, have been associated in the underwater detection and analysis of cosmic radiation flux. The purpose of experiments described in this paper has been to take advantage of the nuclear cosmic-ray related qualities of the ocean water mass by allowing the experimenter(s) to work in situ on the sea floor, rather than attempting to try an impractical alternative: lowering a prepared photoemulsion detector to the bottom from a surface vessel, a method that would yield an unacceptably surface-radiation-cluttered emulsion. This report describes briefly the four elements that motivated or comprised the subject experiment: basic physics which motivated the mission; applied physics, including particle detection, emulsion chemistry, calibration, and scanning; engineering, including design and fabrication of supporting apparatus, use of a submersible (JSL was modified slightly to permit lock-on to the bottom chamber), and a bottom lockout chamber; and operations, including submersible dives, ship support, emulsion preparation, deployment, recovery, and development

  15. DNA barcoding of the Lemnaceae, a family of aquatic monocots

    Directory of Open Access Journals (Sweden)

    Wang Wenqin

    2010-09-01

    Full Text Available Abstract Background Members of the aquatic monocot family Lemnaceae (commonly called duckweeds represent the smallest and fastest growing flowering plants. Their highly reduced morphology and infrequent flowering result in a dearth of characters for distinguishing between the nearly 38 species that exhibit these tiny, closely-related and often morphologically similar features within the same family of plants. Results We developed a simple and rapid DNA-based molecular identification system for the Lemnaceae based on sequence polymorphisms. We compared the barcoding potential of the seven plastid-markers proposed by the CBOL (Consortium for the Barcode of Life plant-working group to discriminate species within the land plants in 97 accessions representing 31 species from the family of Lemnaceae. A Lemnaceae-specific set of PCR and sequencing primers were designed for four plastid coding genes (rpoB, rpoC1, rbcL and matK and three noncoding spacers (atpF-atpH, psbK-psbI and trnH-psbA based on the Lemna minor chloroplast genome sequence. We assessed the ease of amplification and sequencing for these markers, examined the extent of the barcoding gap between intra- and inter-specific variation by pairwise distances, evaluated successful identifications based on direct sequence comparison of the "best close match" and the construction of a phylogenetic tree. Conclusions Based on its reliable amplification, straightforward sequence alignment, and rates of DNA variation between species and within species, we propose that the atpF-atpH noncoding spacer could serve as a universal DNA barcoding marker for species-level identification of duckweeds.

  16. Submersible purification system for radioactive water

    Science.gov (United States)

    Abbott, Michael L.; Lewis, Donald R.

    1989-01-01

    A portable, submersible water purification system for use in a pool of water containing radioactive contamination includes a prefilter for filtering particulates from the water. A resin bed is then provided for removal of remaining dissolved, particulate, organic, and colloidal impurities from the prefiltered water. A sterilizer then sterilizes the water. The prefilter and resin bed are suitably contained and are submerged in the pool. The sterilizer is water tight and located at the surface of the pool. The water is circulated from the pool through the prefilter, resin bed, and sterilizer by suitable pump or the like. In the preferred embodiment, the resin bed is contained within a tank which stands on the bottom of the pool and to which a base mounting the prefilter and pump is attached. An inlet for the pump is provided adjacent the bottom of the pool, while the sterilizer and outlet for the system is located adjacent the top of the pool.

  17. Submersion of alkali clusters in helium nano droplets

    International Nuclear Information System (INIS)

    An der Lan, L.

    2011-01-01

    The interaction of helium nano droplets (HND) with dopants has been an extensively studied Field, both experimentally and theoretically. First papers concerning this topic date back to the late 1960's. Still, on both sides (theory and experiment) were and are loose ends. One of such is the submersion behavior of alkali metals in HND. Although a theory of submersion was developed by Ancilotto et al., which can explain a lot of interesting features in this Field, this particular question (among others) remained unresolved. In 2010, a semiclassi- cal theory was developed by Kresin and Stark, which specifically addressed this problem and gave exact numbers for the critical submersion size. The scope of this doctoral thesis is to continuously build up towards this topic until Finally our results, confirming some of the theoretical Findings, are presented. Especially the critical submersion size for sodium and potassium clusters, 21 and 78, respectively, are confirmed by our experiments. (author) [de

  18. Effects of cold stratification, sulphuric acid, submersion in hot and ...

    African Journals Online (AJOL)

    Effects of cold stratification, sulphuric acid, submersion in hot and tap water pretreatments in the greenhouse and open field conditions on germination of bladder-Senna ( Colutea armena Boiss. and Huet.) seeds.

  19. AWWA E102-17 submersible vertical turbine pumps

    CERN Document Server

    2017-01-01

    This standard describes minimum requirements for submersible vertical turbine pumps utilizing a discharge column pipe assembly, 5 hp or larger, used in water service, including materials, design, manufacture, inspection, and testing.

  20. Characteristics and kinetic studies of Hydrilla verticillata pyrolysis via thermogravimetric analysis.

    Science.gov (United States)

    Hu, Zhiquan; Chen, Zhihua; Li, Genbao; Chen, Xiaojuan; Hu, Mian; Laghari, Mahmood; Wang, Xun; Guo, Dabin

    2015-10-01

    The pyrolysis characteristics and kinetic of Hydrilla verticillata (HV) have been investigated using non-isothermal thermogravimetric analysis. The results showed that the pyrolysis behavior of HV can be divided into two independent stages. The kinetics of Stage I was investigated using a distributed activation energy model (DAEM) with discrete 99 first-order reactions. Stage II was an independent stage which corresponds to the decomposition of calcium oxalate, whose kinetics was studied using iso-conversional method together with compensation effect and master-plots method. The activation energies ranged from 92.39 to 506.17 and 190.42 to 222.48 kJ/mol for the first and second stages respectively. Calculated data gave very good fit to the experimental data. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Monocot leaves are eaten less than dicot leaves in tropical lowland rain forests: correlations with toughness and leaf presentation

    DEFF Research Database (Denmark)

    Grubb, P.J.; Jackson, R.V.; Barberis, I.M.

    2008-01-01

    . It was hypothesized that (a) losses of leaf area to herbivorous invertebrates are generally greatest during leaf expansion and smaller for monocots than for dicots, and (b) where losses after expansion are appreciable any difference between monocots and dicots then is smaller than that found during expansion. Methods......: At six sites on four continents, estimates were made of lamina area loss from the four most recently mature leaves of focal monocots and of the nearest dicot shoot. Measurements of leaf mass per unit area, and the concentrations of water and nitrogen were made for many of the species. In Panama...... of leaf mass per unit area, or concentrations of water or nitrogen. At only one site was the increase in loss from first to fourth mature leaf significant (also large and the same in monocots and dicots), but the losses sustained during expansion were much smaller in the monocots. In the leaf-cutter ant...

  2. Submersible fans and pumps for cryogenic fluids

    International Nuclear Information System (INIS)

    Mark, J.W.

    1986-01-01

    Submersible electric motor driven fans of three sizes have been designed, built and operated at 21 0 K at the Stanford Linear Accelerator Center. The largest is a 100-mm diameter, 2 stage vaneaxial fan with a nominal capacity of 6 L/s at 2 m head. It is driven by a 4 pole, 3 phase induction motor that runs at 1750 rpm. The next smaller one is an 85-mm diameter centrifugal pump. It pumps 3 L/s at a head of 5 m. The third is a 75-mm single stage vaneaxial fan with a nominal capacity is 3 L/s at a head of 2 m. The 85-mm pump and the 75-mm fan are driven by 2 pole, 3 phase induction motors running at 3550 rpm. The motors were modified to operate submerged in the cryogenic fluid. The pumps have been operated in liquid hydrogen, liquid deuterium, and pressurized helium gas at 21 0 K. They can also operate with denser fluids such as liquid nitrogen, but rotational speed, capacity, and head will be reduced. They have been operated while submerged in liquid helium

  3. Class B Gene Expression and the Modified ABC Model in Nongrass Monocots

    Directory of Open Access Journals (Sweden)

    Akira Kanno

    2007-01-01

    Full Text Available The discovery of the MADS-box genes and the study of model plants such as Arabidopsis thaliana and Antirrhinum majus have greatly improved our understanding of the molecular mechanisms driving the diversity in floral development. The class B genes, which belong to the MADS-box gene family, are important regulators of the development of petals and stamens in flowering plants. Many nongrass monocot flowers have two whorls of petaloid organs, which are called tepals. To explain this floral morphology, the modified ABC model was proposed. This model was exemplified by the tulip, in which expansion and restriction of class B gene expression is linked to the transition of floral morphologies in whorl 1. The expression patterns of class B genes from many monocot species nicely fit this model; however, those from some species, such as asparagus, do not. In this review, we summarize the relationship between class B gene expression and floral morphology in nongrass monocots, such as Liliales (Liliaceae and Asparagales species, and discuss the applicability of the modified ABC model to monocot flowers.

  4. Plastid Phylogenomic Analyses Resolve Tofieldiaceae as the Root of the Early Diverging Monocot Order Alismatales.

    Science.gov (United States)

    Luo, Yang; Ma, Peng-Fei; Li, Hong-Tao; Yang, Jun-Bo; Wang, Hong; Li, De-Zhu

    2016-04-06

    The predominantly aquatic order Alismatales, which includes approximately 4,500 species within Araceae, Tofieldiaceae, and the core alismatid families, is a key group in investigating the origin and early diversification of monocots. Despite their importance, phylogenetic ambiguity regarding the root of the Alismatales tree precludes answering questions about the early evolution of the order. Here, we sequenced the first complete plastid genomes from three key families in this order:Potamogeton perfoliatus(Potamogetonaceae),Sagittaria lichuanensis(Alismataceae), andTofieldia thibetica(Tofieldiaceae). Each family possesses the typical quadripartite structure, with plastid genome sizes of 156,226, 179,007, and 155,512 bp, respectively. Among them, the plastid genome ofS. lichuanensisis the largest in monocots and the second largest in angiosperms. Like other sequenced Alismatales plastid genomes, all three families generally encode the same 113 genes with similar structure and arrangement. However, we detected 2.4 and 6 kb inversions in the plastid genomes ofSagittariaandPotamogeton, respectively. Further, we assembled a 79 plastid protein-coding gene sequence data matrix of 22 taxa that included the three newly generated plastid genomes plus 19 previously reported ones, which together represent all primary lineages of monocots and outgroups. In plastid phylogenomic analyses using maximum likelihood and Bayesian inference, we show both strong support for Acorales as sister to the remaining monocots and monophyly of Alismatales. More importantly, Tofieldiaceae was resolved as the most basal lineage within Alismatales. These results provide new insights into the evolution of Alismatales as well as the early-diverging monocots as a whole. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  5. In tropical lowland rain forests monocots have tougher leaves than dicots, and include a new kind of tough leaf.

    Science.gov (United States)

    Dominy, Nathaniel J; Grubb, Peter J; Jackson, Robyn V; Lucas, Peter W; Metcalfe, Daniel J; Svenning, Jens-Christian; Turner, Ian M

    2008-06-01

    There has been little previous work on the toughness of the laminae of monocots in tropical lowland rain forest (TLRF) despite the potential importance of greater toughness in inhibiting herbivory by invertebrates. Of 15 monocot families with >100 species in TLRF, eight have notably high densities of fibres in the lamina so that high values for toughness are expected. In north-eastern Australia punch strength was determined with a penetrometer for both immature leaves (approx. 30 % final area on average) and fully expanded, fully toughened leaves. In Singapore and Panama, fracture toughness was determined with an automated scissors apparatus using fully toughened leaves only. In Australia punch strength was, on average, 7x greater in shade-tolerant monocots than in neighbouring dicots at the immature stage, and 3x greater at the mature stage. In Singapore, shade-tolerant monocots had, on average, 1.3x higher values for fracture toughness than neighbouring dicots. In Panama, both shade-tolerant and gap-demanding monocots were tested; they did not differ in fracture toughness. The monocots had markedly higher values than the dicots whether shade-tolerant or gap-demanding species were considered. It is predicted that monocots will be found to experience lower rates of herbivory by invertebrates than dicots. The tough monocot leaves include both stiff leaves containing relatively little water at saturation (e.g. palms), and leaves which lack stiffness, are rich in water at saturation and roll readily during dry weather or even in bright sun around midday (e.g. gingers, heliconias and marants). Monocot leaves also show that it is possible for leaves to be notably tough throughout the expansion phase of development, something never recorded for dicots. The need to broaden the botanist's mental picture of a 'tough leaf' is emphasized.

  6. Submersed macrophytes as indicators of the nutrient burden of Lake Constance (Untersee)

    International Nuclear Information System (INIS)

    Schmieder, K.

    1992-01-01

    Most of the submersed species react sensitively to changes in the site conditions during the investigation period; this shows the high value of submersed macrophytes as biological indicators of water pollution. (orig./EF) [de

  7. Use of sediment CO2 by submersed rooted plants

    DEFF Research Database (Denmark)

    Winkel, Anders; Borum, Jens

    2009-01-01

    freshwater plants with different morphology and growth characteristics (Lobelia dortmanna, Lilaeopsis macloviana, Ludwigia repens, Vallisneria americana and Hydrocotyle verticillata) are able to support photosynthesis supplied by uptake of CO2 from the sediment. Methods: Gross photosynthesis was measured......Background and Aims: Submersed plants have different strategies to overcome inorganic carbon limitation. It is generally assumed that only small rosette species (isoetids) are able to utilize the high sediment CO2 availability. The present study examined to what extent five species of submersed......, the shoot to root ratio on an areal basis was the single factor best explaining variability in the importance of sediment CO2. For Ludwigia, diffusion barriers limited uptake or transport from roots to stems and transport from stems to leaves. Conclusions: Submersed plants other than isoetids can utilize...

  8. 77 FR 65360 - Grant of Authority for Subzone Status (Centrifugal and Submersible Pumps); Auburn, NY

    Science.gov (United States)

    2012-10-26

    ... Status (Centrifugal and Submersible Pumps); Auburn, NY Pursuant to its authority under the Foreign-Trade... authority to establish a special-purpose subzone at the centrifugal and submersible pump manufacturing and... submersible pumps and related controllers at the Xylem Water Systems U.S.A., LLC, facilities located in Auburn...

  9. Application of ADM1 for modeling of biogas production from anaerobic digestion of Hydrilla verticillata.

    Science.gov (United States)

    Chen, Xiaojuan; Chen, Zhihua; Wang, Xun; Huo, Chan; Hu, Zhiquan; Xiao, Bo; Hu, Mian

    2016-07-01

    The present study focused on the application of anaerobic digestion model no. 1 (ADM1) to simulate biogas production from Hydrilla verticillata. Model simulation was carried out by implementing ADM1 in AQUASIM 2.0 software. Sensitivity analysis was used to select the most sensitive parameters for estimation using the absolute-relative sensitivity function. Among all the kinetic parameters, disintegration constant (kdis), hydrolysis constant of protein (khyd_pr), Monod maximum specific substrate uptake rate (km_aa, km_ac, km_h2) and half-saturation constants (Ks_aa, Ks_ac) affect biogas production significantly, which were optimized by fitting of the model equations to the data obtained from batch experiments. The ADM1 model after parameter estimation was able to well predict the experimental results of daily biogas production and biogas composition. The simulation results of evolution of organic acids, bacteria concentrations and inhibition effects also helped to get insight into the reaction mechanisms. Copyright © 2016. Published by Elsevier Ltd.

  10. Acclimation of Hydrilla verticillata to sediment anoxia in vegetation restoration in eutrophic waters.

    Science.gov (United States)

    Wu, Juan; Dai, Yanran; Rui, Shengyang; Cui, Naxin; Zhong, Fei; Cheng, Shuiping

    2015-12-01

    Sediment anoxia generally results from intense organic enrichment and is a limiting factor in the restoration of vegetation in eutrophic waters. To investigate the effect of sediment anoxia on a typical pollution-tolerant submerged macrophyte species, Hydrilla verticillata, and acclimation mechanisms in the plant, a gradient of sediment anoxia was simulated with additions of sucrose to the sediment, which can stimulate increased concentrations of total nitrogen, NH4(+) and Fe in pore water. H. verticillata growth was significantly affected by highly anoxic conditions, as indicated by reduced total biomass in the 0.5 and 1% sucrose treatments. However, slight anoxia (0.1% sucrose addition) promoted growth, and the shoot biomass was 22.64% higher than in the control. In addition to morphologic alterations, H. verticillata showed physiological acclimations to anoxia, including increased anaerobic respiration and changes in carbon and nitrogen metabolism in roots. The soluble protein and soluble carbohydrate contents in roots of the 1% treatment were both significantly higher compared with those in the control. The increase in alcohol dehydrogenase activity and pyruvate content in the roots suggested that H. verticillata has a well-developed capacity for anaerobic fermentation. This study suggests that highly anoxic sediments inhibit the growth of H. verticillata and the species has a degree of tolerance to anoxic conditions. Further in situ investigations should be conducted on the interactions between sediment conditions and macrophytes to comprehensively evaluate the roles of sediment in the restoration of vegetation in eutrophic waters.

  11. Effects of the decomposing liquid of Cladophora oligoclona on Hydrilla verticillata turion germination and seedling growth.

    Science.gov (United States)

    Zhang, Lu; Peng, Xue; Liu, Biyun; Zhang, Yi; Zhou, Qiaohong; Wu, Zhenbin

    2018-08-15

    Excessive proliferation of filamentous green algae (FGA) has been considered an important factor resulting in the poor growth or even decline of submerged macrophytes. However, there is a lack of detailed information regarding the effect of decaying FGA on submerged macrophytes. This study aimed to investigate whether the decomposing liquid from Cladophora oligoclona negatively affects Hydrilla verticillata turion germination and seedling growth. The results showed that the highest concentrations of decomposing liquid treatments inhibited the turion germination rate, which was the lowest than other treatments, at only 84%. The chlorophyll a fluorescence (JIP test) and physiological indicators (chlorophyll a content, soluble sugars, Ca 2+ /Mg 2+ -ATPase and PAL activity) were also measured. The chlorophyll a content in the highest concentration (40% of original decomposing liquid) treatment group decreased by 43.53% than that of the control; however, soluble sugars, Ca 2+ /Mg 2+ -ATPase, and PAL activity increased by 172.46%, 271.19%, and 26.43% respectively. The overall results indicated that FGA decay has a considerable effect on submerged macrophyte turion germination and seedling growth, which could inhibit their expansion and reproduction. This study emphasized the need to focus on effects of FGA decomposition on the early growth stages of submerged macrophytes and offered technological guidance for submerged vegetation restoration in lakes and shallow waters. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. In tropical lowland rain forests monocots have tougher leaves than dicots, and include a new kind of tough leaf

    DEFF Research Database (Denmark)

    Dominy, N.J.; Grubb, P.J.; Jackson, R.V.

    2008-01-01

    -tolerant or gap-demanding species were considered. Conclusions: It is predicted that monocots will be found to experience lower rates of herbivory by invertebrates than dicots. The tough monocot leaves include both stiff leaves containing relatively little water at saturation (e.g. palms), and leaves which lack...... stiffness, are rich in water at saturation and roll readily during dry weather or even in bright sun around midday (e.g. gingers, heliconias and marants). Monocot leaves also show that it is possible for leaves to be notably tough throughout the expansion phase of development, something never recorded...... for dicots. The need to broaden the botanist's mental picture of a ‘tough leaf' is emphasized.   Key words: Dicots, fracture toughness, herbivory, leaves, monocots, punch strength, tropical rain forest  ...

  13. Machine Visual Guidance For An Autonomous Undersea Submersible

    Science.gov (United States)

    Nguyen, Hoa G.; Kaomea, Peter K.; Heckman, Paul J.

    1988-12-01

    Optical imaging is the preferred sensory modality for underwater robotic activities requiring high resolution at close range, such as station keeping, docking, control of manipulator, and object retrieval. Machine vision will play a vital part in the design of next generation autonomous underwater submersibles. This paper describes an effort to demonstrate that real-time vision-based guidance and control of autonomous underwater submersibles is possible with compact, low-power, and vehicle-imbeddable hardware. The Naval Ocean Systems Center's EAVE-WEST (Experimental Autonomous Vehicle-West) submersible is being used as the testbed. The vision hardware consists of a PC-bus video frame grabber and an IBM-PC/AT compatible single-board computer, both residing in the artificial intelligence/vision electronics bottle of the submersible. The specific application chosen involves the tracking of underwater buoy cables. Image recognition is performed in two steps. Feature points are identified in the underwater video images using a technique which detects one-dimensional local brightness minima and maxima. Hough transformation is then used to detect the straight line among these feature points. A hierarchical coarse-to-fine processing method is employed which terminates when enough feature points have been identified to allow a reliable fit. The location of the cable identified is then reported to the vehicle controller computer for automatic steering control. The process currently operates successfully with a throughput of approximately 2 frames per second.

  14. IMPACT OF SUBMERSIBLE PUMPS ON PB CONSTITUENTS IN RESIDENTIAL WELLS

    Science.gov (United States)

    Dissolved lead in 51 domestic wells screened from 18 m to 48 m in glacial tills and outwash deposits were examined, from archived samples collected during 2001-2004, in conjunction with respective submersible pump characteristics. Pb concentrations of these residential water supp...

  15. Study on velocity distribution in a pool by submersible mixers

    International Nuclear Information System (INIS)

    Tian, F; Shi, W D; Lu, X N; Chen, B; Jiang, H

    2012-01-01

    To study the distribution of submersible mixers and agitating effect in the sewage treatment pool, Pro/E software was utilized to build the three-dimensional model. Then, the large-scale computational fluid dynamics software FLUENT6.3 was used. ICEM software was used to build unstructured grid of sewage treatment pool. After that, the sewage treatment pool was numerically simulated by dynamic coordinate system technology and RNG k-ε turbulent model and PIOS algorithm. The macro fluid field and each section velocity flow field distribution were analyzed to observe the efficiency of each submersible mixer. The average velocity and mixing area in the sewage pool were studied simultaneously. Results show that: the preferred project B, two submersible mixers speed is 980 r/min, and setting angles are all 30°. Fluid mixing area in the pool has reached more than 95%. Under the action of two mixers, the fluid in the sewage pool form a continuous circulating water flow. The fluid is mixed adequately and average velocity of fluid in the pool is at around 0.241m/s, which agreed with the work requirements. Consequently it can provide a reference basis for practical engineering application of submersible mixers by using this method.

  16. Submersible microbial fuel cell for electricity production from sewage sludge

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Olias, Lola Gonzalez; Kongjan, Prawit

    2010-01-01

    A submersible microbial fuel cell (SMFC) was utilized to treatment of sewage sludge and simultaneous generate electricity. Stable power generation (145±5 mW/m2) was produced continuously from raw sewage sludge for 5.5 days. The corresponding total chemical oxygen demand (TCOD) removal efficiency...... of an effective system to treatment of sewage sludge and simultaneous recover energy....

  17. Evaluation of uranium removal by Hydrilla verticillata (L.f.) Royle from low level nuclear waste under laboratory conditions.

    Science.gov (United States)

    Srivastava, Sudhakar; Bhainsa, K C

    2016-02-01

    The present study evaluated uranium (U) removal ability and tolerance to low level nuclear waste (LLNW) of an aquatic weed Hydrilla verticillata. Plants were screened for growth in 10%-50% waste treatments up to 3 d. Treatments of 20% and 50% waste imposed increasing toxicity with duration assessed in terms of change in fresh weight and in the levels of photosynthetic pigments and thiobarbituric acid-reactive substances. U concentration, however, did not show a progressive increase and was about 42 μg g(-1) dw from 20% to 50% waste at 3 d. This suggested that a saturation stage was reached with respect to U removal due to increasing toxicity. However, in another experiment with 10% waste and 10% waste+10 ppm U treatments, plants showed an increase in U concentration with the maximum level approaching 426 μg g(-1) dw at 3 d without showing any toxicity as compared to that at 20% and 50% waste treatments. Hence, plants possessed significant potential to take up U and toxicity of LLNW limited their U removal ability. This implies that the use of Hydrilla plants for U removal from LLNW is feasible at low concentrations and would require repeated harvesting at short intervals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Reinvestigating an enigmatic Late Cretaceous monocot: morphology, taxonomy, and biogeography of Viracarpon

    Directory of Open Access Journals (Sweden)

    Kelly K.S. Matsunaga

    2018-04-01

    Full Text Available Angiosperm-dominated floras of the Late Cretaceous are essential for understanding the evolutionary, ecological, and geographic radiation of flowering plants. The Late Cretaceous–early Paleogene Deccan Intertrappean Beds of India contain angiosperm-dominated plant fossil assemblages known from multiple localities in central India. Numerous monocots have been documented from these assemblages, providing a window into an important but poorly understood time in their diversification. One component of the Deccan monocot diversity is the genus Viracarpon, known from anatomically preserved infructescences. Viracarpon was first collected over a century ago and has been the subject of numerous studies. However, resolution of its three-dimensional (3D morphology and anatomy, as well as its taxonomic affinities, has remained elusive. In this study we investigated the morphology and taxonomy of genus Viracarpon, combining traditional paleobotanical techniques and X-ray micro-computed tomography (μCT. Re-examination of type and figured specimens, 3D reconstructions of fruits, and characterization of structures in multiple planes of section using μCT data allowed us to resolve conflicting interpretations of fruit morphology and identify additional characters useful in refining potential taxonomic affinities. Among the four Viracarpon species previously recognized, we consider two to be valid (Viracarpon hexaspermum and Viracarpon elongatum, and the other two to be synonyms of these. Furthermore, we found that permineralized infructescences of Coahuilocarpon phytolaccoides from the late Campanian of Mexico correspond closely in morphology to V. hexaspermum. We argue that Viracarpon and Coahuilocarpon are congeneric and provide the new combination, Viracarpon phytolaccoides (Cevallos-Ferriz, Estrada-Ruiz & Perez-Hernandez Matsunaga, S.Y. Smith, & Manchester comb. nov. The significant geographic disjunction between these two occurrences indicates that the

  19. Submersible microbial fuel cell for electricity production from sewage sludge

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Olias, Lola Gonzalez; Kongjan, Prawit

    2011-01-01

    A submersible microbial fuel cell (SMFC) was utilized to treat sewage sludge and simultaneously generate electricity. Stable power generation (145± 5 mW/m2, 470 Ω) was produced continuously from raw sewage sludge for 5.5 days. The maximum power density reached 190±5 mW/m2. The corresponding total...... system to treat sewage sludge and simultaneously recover energy....

  20. What can be done about corrosion in submersible pumps?

    Energy Technology Data Exchange (ETDEWEB)

    Minett, S.

    2000-09-01

    Useful advice and a survey of materials and techniques which can help counter corrosion risks in submersible pumps are provided. The greatest risk of corrosion is caused by sea water, hydrochloric acid, certain types of solvents, hydrogen sulphide, liquids with a high copper content, bases with a high pH value and certain liquids containing a mixture of acids. Counteractive strategies suggested include using a corrosion resistant material such as stainless steel, or other resistant coatings and materials for particular components that are exposed to high corrosion risks. Most submersible pumps are made of cast iron which should present no corrosion problems in normal domestic use. In mining and construction applications aluminum submersibles are common, which is resistant to a pH value of about 8. The use of stainless steel is recommended as the main material in submersible pumps when used for pumping acidic liquids, and when purity of the liquid pumped is of prime consideration. Coatings and anodes on conventional cast iron pumps are a less expensive and more flexible alternative against salt water corrosion. Among coatings epoxy coating is the most widely used. Zinc anodes are used in conjunction with epoxy coatings, which by setting up a micro current by contact with the cast iron prevent corrosion of areas of the cast iron that may be exposed as a result of post-production scratching. By being sacrificially corroded, the zinc anodes thus significantly extend the life of a coated pump. Impressed current from an external power source, is an effective, but more expensive alternative to the implanted anode method. Using resistant materials such as nitrile rubber, fluoro-carbon rubber, corrosion resistant cemented carbide, or chlorinated rubber for various components (rotating shaft seals, rubber 'O' rings, cable sheathing, etc) are other alternatives that may be depending on the application and the degree of exposure.

  1. Issues in offshore platform research - Part 1: Semi-submersibles

    Science.gov (United States)

    Sharma, R.; Kim, Tae-Wan; Sha, O. P.; Misra, S. C.

    2010-09-01

    Availability of economic and efficient energy resources is crucial to a nation's development. Because of their low cost and advancement in drilling and exploration technologies, oil and gas based energy systems are the most widely used energy source throughout the world. The inexpensive oil and gas based energy systems are used for everything, i.e., from transportation of goods and people to the harvesting of crops for food. As the energy demand continues to rise, there is strong need for inexpensive energy solutions. An offshore platform is a large structure that is used to house workers and machinery needed to drill wells in the ocean bed, extract oil and/or natural gas, process the produced fluids, and ship or pipe them to shore. Depending on the circumstances, the offshore platform can be fixed (to the ocean floor) or can consist of an artificial island or can float. Semi-submersibles are used for various purposes in offshore and marine engineering, e.g. crane vessels, drilling vessels, tourist vessels, production platforms and accommodation facilities, etc. The challenges of deepwater drilling have further motivated the researchers to design optimum choices for semi-submersibles for a chosen operating depth. In our series of eight papers, we discuss the design and production aspects of all the types of offshore platforms. In the present part I, we present an introduction and critical analysis of semi-submersibles.

  2. Issues in offshore platform research - Part 1: Semi-submersibles

    Directory of Open Access Journals (Sweden)

    R. Sharma

    2010-09-01

    Full Text Available Availability of economic and efficient energy resources is crucial to a nation's development. Because of their low cost and advancement in drilling and exploration technologies, oil and gas based energy systems are the most widely used energy source throughout the world. The inexpensive oil and gas based energy systems are used for everything, i.e., from transportation of goods and people to the harvesting of crops for food. As the energy demand continues to rise, there is strong need for inexpensive energy solutions. An offshore platform is a large structure that is used to house workers and machinery needed to drill wells in the ocean bed, extract oil and/or natural gas, process the produced fluids, and ship or pipe them to shore. Depending on the circumstances, the offshore platform can be fixed (to the ocean floor or can consist of an artificial island or can float. Semi-submersibles are used for various purposes in offshore and marine engineering, e.g. crane vessels, drilling vessels, tourist vessels, production platforms and accommodation facilities, etc. The challenges of deepwater drilling have further motivated the researchers to design optimum choices for semi-submersibles for a chosen operating depth. In our series of eight papers, we discuss the design and production aspects of all the types of offshore platforms. In the present part I, we present an introduction and critical analysis of semi-submersibles.

  3. WTEC panel report on research submersibles and undersea technologies

    Science.gov (United States)

    Seymore, Richard J.; Blidberg, D. Richard; Brancart, Claude P.; Gentry, Larry L.; Kalvaitis, Algis N.; Lee, Michael J.; Mooney, Brad; Walsh, Don

    1994-06-01

    This report covers research submersibles and related subsea technologies in Finland, France, Russia, Ukraine and the United Kingdom. Manned, teleoperated, and autonomous submersibles were of interest. The panel found that, in contrast to the United States, Europe is making substantial progress in cooperative and coordinated research in subsea technology, including the development of standards. France is a leader in autonomous vehicle technology. Because much less was known a priori about the technologies in Russia and Ukraine, there were more new findings in those countries than in those Western European nations visited. However, Russia and Ukraine have a sizeable (and currently underutilized) infrastructure in this field, including a highly educated and experienced manpower pool, impressive (in some cases unique) facilities for physical testing, extensive fleets of seagoing research vessels capable of long voyages, and state-of-the-art facilities for conducting oceanographic investigations. The panel visited newly-formed commercial companies associated with long-standing submersible R&D and production centers in Russia and Ukraine. So far, these new efforts are undercapitalized, and as such represent opportunities at very low cost for Western nations, as detailed in the site reports.

  4. Morphogenic Regulators Baby boom and Wuschel Improve Monocot Transformation[OPEN

    Science.gov (United States)

    Lowe, Keith; Wu, Emily; Cho, Myeong-Je; Lenderts, Brian; Chamberlin, Mark; Cushatt, Josh; Ryan, Larisa; Khan, Tanveer; Chow-Yiu, Julia; Hua, Wei; Banh, Jenny; Bao, Zhongmeng; Brink, Kent; Igo, Elizabeth; Rudrappa, Bhojaraja; Shamseer, PM; Shen, Bo; Zheng, Peizhong; Bidney, Dennis; Falco, Carl; Zhao, Zuo-Yu; Xu, Deping

    2016-01-01

    While transformation of the major monocot crops is currently possible, the process typically remains confined to one or two genotypes per species, often with poor agronomics, and efficiencies that place these methods beyond the reach of most academic laboratories. Here, we report a transformation approach involving overexpression of the maize (Zea mays) Baby boom (Bbm) and maize Wuschel2 (Wus2) genes, which produced high transformation frequencies in numerous previously nontransformable maize inbred lines. For example, the Pioneer inbred PHH5G is recalcitrant to biolistic and Agrobacterium tumefaciens transformation. However, when Bbm and Wus2 were expressed, transgenic calli were recovered from over 40% of the starting explants, with most producing healthy, fertile plants. Another limitation for many monocots is the intensive labor and greenhouse space required to supply immature embryos for transformation. This problem could be alleviated using alternative target tissues that could be supplied consistently with automated preparation. As a major step toward this objective, we transformed Bbm and Wus2 directly into either embryo slices from mature seed or leaf segments from seedlings in a variety of Pioneer inbred lines, routinely recovering healthy, fertile T0 plants. Finally, we demonstrated that the maize Bbm and Wus2 genes stimulate transformation in sorghum (Sorghum bicolor) immature embryos, sugarcane (Saccharum officinarum) callus, and indica rice (Oryza sativa ssp indica) callus. PMID:27600536

  5. A new commelinid monocot seed fossil from the early Eocene previously identified as Solanaceae.

    Science.gov (United States)

    Särkinen, Tiina; Kottner, Sören; Stuppy, Wolfgang; Ahmed, Farah; Knapp, Sandra

    2018-01-01

    Fossils provide minimum age estimates for extant lineages. Here we critically evaluate Cantisolanum daturoides Reid & Chandler and two other early putative seed fossils of Solanaceae, an economically important plant family in the Asteridae. Three earliest seed fossil taxa of Solanaceae from the London Clay Formation (Cantisolanum daturoides) and the Poole and Branksome Sand Formations (Solanum arnense Chandler and Solanispermum reniforme Chandler) were studied using x-ray microcomputed tomography (MCT) and scanning electron microscopy (SEM). The MCT scans of Cantisolanum daturoides revealed a high level of pyrite preservation at the cellular level. Cantisolanum daturoides can be clearly excluded from Solanaceae and has more affinities to the commelinid monocots based on a straight longitudinal axis, a prominent single layer of relatively thin-walled cells in the testa, and a clearly differentiated micropyle surrounded by radially elongated and inwardly curved testal cells. While the MCT scans show no internal preservation in Solanum arnense and Solanispermum reniforme, SEM images show the presence of several characteristics that allow the placement of these taxa at the stem node of Solanaceae. Cantisolanum daturoides is likely a member of commelinid monocots and not Solanaceae as previously suggested. The earliest fossil record of Solanaceae is revised to consist of fruit fossil with inflated calyces from the early Eocene of Patagonia (52 Ma) and fossilized seeds from the early to mid-Eocene of Europe (48-46 Ma). The new identity for Cantisolanum daturoides does not alter a late Cretaceous minimum age for commelinids. © 2018 Botanical Society of America.

  6. New methods for the analysis of invasion processes: multi-criteria evaluation of the invasion of Hydrilla verticillata in Guatemala.

    Science.gov (United States)

    Monterroso, I; Binimelis, R; Rodríguez-Labajos, B

    2011-03-01

    The study described in this article incorporates stakeholders' views on aquatic invasion processes and combines expert analysis with information from field work into an evaluation exercise. Management scenarios are designed based on available technical data and stakeholders' perceptions. These scenarios are evaluated using the Social Multi-Criteria Evaluation framework employing the NAIADE model. Two evaluations are carried out, technical and social. Social acceptance of different management scenarios, distribution of costs and benefits, and attribution of responsibility are discussed. The case study was carried out on Lake Izabal, a body of water connected to the Caribbean Sea in Northeastern Guatemala. In 2000, local fishermen reported the presence of an alien species in the lake, the macrophyte Hydrilla verticillata. Two years later, this alien species was established around the entire lakeshore, damaging the ecosystem, endangering native species and the subsistence of local inhabitants through impacts on transportation, fishing practices, and tourism. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. A new concept of submersed centrifugal pump protection

    International Nuclear Information System (INIS)

    Ribeiro, Fabiano U.; Aguiar, Jose Luiz de M.; Hamdan, Adel C.; Doerwald, Bruno K.; Dutra, Diogenes; Ghiotto, Edson Carlos da S.; Meira, Marco Antonio A. de

    2000-01-01

    The present article is related to the development of one motor protection relay, which features include the electrical and mechanical device protection of machine. The main focus the purpose of this development, was the monitoring of the phenomena called 'Back Spin', which is common in oil production plant where 'Electrical Submersible Pump' (ESP) Technologies is used. The final results of this job is to present one equipment which is capable to completely protect the ESP Set, electrically and mechanically, and with additional functions of monitoring the mechanical set, with graphic interface to set all protection and monitoring functions using 'windows based' tools. (author)

  8. Main Alkaloids of Peganum harmala L. and Their Different Effects on Dicot and Monocot Crops

    Directory of Open Access Journals (Sweden)

    Chi Zhang

    2013-02-01

    Full Text Available Alkaloids with allelopathic activity are not as well-known as other allelochemicals. Our study revealed that total alkaloids from seeds of the medicinal plant Peganum harmala L. possessed significant growth inhibitory effect on four treated plants, with dicot plants (lettuce and amaranth being more sensitive than the tested monocot plants (wheat and ryegrass. Further investigation led to the isolation of harmaline and harmine as the main active ingredients in the total alkaloids of P. harmala seeds. Harmaline exerted potent inhibitory effects on seedling growth of treated plants, especially dicots, inhibiting root elongation of lettuce and amaranth by 31% and 47% at a very low concentration (5 µg/mL, whereas harmine exhibited much weaker non-selective inhibitory effect on the plants. Considering the high yield and poor utilization of P. harmala in China, we anticipate that this plant could be exploited as an alternative weed management tool in the future.

  9. 36 CFR 3.19 - May I operate a submersible within park waters?

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false May I operate a submersible within park waters? 3.19 Section 3.19 Parks, Forests, and Public Property NATIONAL PARK SERVICE... waters? The use of manned or unmanned submersibles may only occur in accordance with a permit issued by...

  10. Size effect related to damping caused by water submersion

    International Nuclear Information System (INIS)

    Dong, R.G.

    1981-01-01

    An important effect of water submersion on the dynamic response of a structure is the increase in effective damping. The dynamic response of submerged structures is of interest in the nuclear power industry for reasons of operational safety during seismic and other dynamic excitations. In this paper, the added damping contribution that results from the viscosity of water and the dependence of the contribution on structural size are examined. Other factors considered are the applicable range of viscous damping with respect to displacement amplitude and, as far as damping is concerned, how far neighboring members must be from each other to respond as if in open water. An expression is derived for relating the damping value to structural size. Estimated added-damping values for representative fuel elements, fuel bundles, and main steam-pressure-relief-valve lines are given based on our derived expression for added damping

  11. Special considerations for electric submersible pump applications in underpressured reservoirs

    International Nuclear Information System (INIS)

    Powers, M.L.

    1991-01-01

    This paper investigates the effect of electric submersible pump performance tolerances and minor speed variations on the producing rate of wells completed in underpressured reservoirs, and presents ESP design considerations which are unique for this class of wells. These wells require considerable head to initiate flow and have relatively flat well-load curves. Pumps that operate near their maximum recommended rate have steep performance curves. it is shown that this minimizes the effect of an underperforming pump on producing rate. Equations are developed for calculating the effects of pump performance and speed. Application requires evaluating the slopes of the pump performance curve and well-load curve at design rate. Utility of these equations is demonstrated by practical examples. It is also demonstrated that flow-stall can easily occur in underpressured reservoir applications when pumps designed to operate near their minimum recommended rate are installed

  12. Anchoring submersible ultrasonic receivers in river channels with stable substrate

    Science.gov (United States)

    Bettoli, Phillip William; Scholten, G.D.; Hubbs, D.

    2010-01-01

    We developed an anchoring system for submersible ultrasonic receivers (SURs) that we placed on the bottom of the riverine reaches of three main-stem reservoirs in the upper Tennessee River. Each anchor consisted of a steel tube (8.9 x 35.6 cm) welded vertically to a round plate of steel (5.1 x 40.6 cm). All seven SURs and their 57-kg anchors were successfully deployed and retrieved three times over 547 d by a dive team employing surface air-breathing equipment and a davit-equipped boat. All of the anchors and their SURs remained stationary over two consecutive winters on the hard-bottom, thalweg sites where they were deployed. The SUR and its anchor at the most downriver site experienced flows that exceeded 2,100 m(3)/s and mean water column velocities of about 0.9 m/s.

  13. Using Multispectral Sentinel-2 Data to Monitor Submerse Macrophytes

    Science.gov (United States)

    Wolf, Patrick; Roessler, Sebastian; Schneider, Thomas; Melzer, Arnulf

    2012-04-01

    Due to climate change and the involved temperatures of Bavarian freshwater lakes, the invasive submerse macrophytes Elodea nuttallii and Najas marina exhibit a massive expansion. To map these processes, a monitoring system based on remote sensing methods is under development. The main part of the monitoring system is a coupled reflection-/growth-model, which derives biometrical parameters for the EU water framework directive (WFD) by inversion of the reflectance spectra. For operational monitoring tasks a high revisiting time is necessary. Hence, the Sentinel-2 sensor might be very promising, as filling the gap between RapidEye and WorldView2 and between hyperspectral an aerial images. This paper outlines principles, methods and first results of the project.

  14. Performance evaluation of a transformerless multiphase electric submersible pump system

    Directory of Open Access Journals (Sweden)

    Ahmed A. Hakeem

    2014-08-01

    Full Text Available Using of low-voltage variable-frequency drive followed by a step-up transformer is the most preferable way to feed an electrical submersible pump motor. The existence of long feeder between the motor and drive systems usually causes over-voltage problems because of the travelling wave phenomenon, which makes the employment of filter networks on the motor or inverter terminals mandatory. The so-called boost-inverter inherently can solve this problem with filter-less operation as it offers a direct sinusoidal output voltage. As boost inverters have voltage boosting capability, it can provide a transformer-less operation as well. This study investigates the performance of a five-phase modular winding induction machine fed from a boost-inverter through a long feeder. A simulation study using a 1000 Hp system and experimental investigation on a 1 Hp prototype machine are used to support the presented approach.

  15. Submersion Quenching of Undercooled Liquid Metals in an Electrostatic Levitator

    Science.gov (United States)

    SanSoucie, Michael P.; Rogers, Jan R.

    2016-01-01

    The NASA Marshall Space Flight Center (MSFC) electrostatic levitation (ESL) laboratory has a long history of providing materials research and thermophysical property data. The laboratory has recently added a new capability, a rapid quench system. This system allows samples to be dropped into a quench vessel that can be filled with a low melting point material, such as a gallium or indium alloy. Thereby allowing rapid quenching of undercooled liquid metals and alloys. This is the first submersion quench system inside an electrostatic levitator. The system has been tested successfully with samples of zirconium, iron-cobalt alloys, titanium-zirconium-nickel alloys, and silicon-cobalt alloys. This rapid quench system will allow materials science studies of undercooled materials and new materials development, including studies of metastable phases and transient microstructures. In this presentation, the system is described and some initial results are presented.

  16. Evaluation of invasions and declines of submersed aquatic macrophytes

    Science.gov (United States)

    Chambers, P.A.; Barko, J.W.; Smith, C.S.

    1993-01-01

    During the past 60 yr, sightings of aquatic macrophyte species in geographic regions where they had previously not been found have occurred with increasing frequency, apparently due to both greater dispersal of the plants as a result of human activities as well as better documentation of plant distribution. Intercontinental invasions, such as Myriophyllum spicatum and Hydrilla into North America, Elodea canadensis into Europe and Elodea nuttallii, Egeria densa and Cabomba caroliniana into Japan, have generally been well documented. However, the spread of an exotic species across a continent after its initial introduction (e.g., Potamogeton crispus in North America) or the expansion of a species native to a continent into hitherto unexploited territory (e.g.,the expansion of the North American native Myriophyllum heterophyllum into New England) have received little attention. Natural declines in aquatic macrophyte communities have also received little scientific study although there are many accounts of macrophyte declines. The best-documented example comes from the marine literature where extensive declines of eelgrass (Zostera) occurred in the 1930s along the Atlantic coast due to a pathogenic marine slime mold (''wasting disease''). The aim of this workshop was to identify examples of invasions or natural declines of aquatic macrophyte species throughout the world and assess the importance of environmental factors in their control. Forty-five scientists and aquatic plant managers from ten countries participated in the workshop. Eleven of the participants contributed written evaluations of species invasions and declines in their geo-graphic region. These were distributed to registered participants prior to the meeting and served as the starting-point of workshop discussions. To address the topics raised in the working papers, the participants divided into four working groups to evaluate: 1. Environmental controls of species invasions. 2. Biotic controls of species

  17. Multiple Origins and Nested Cycles of Hybridization Result in High Tetraploid Diversity in the Monocot Prospero.

    Science.gov (United States)

    Jang, Tae-Soo; Parker, John S; Emadzade, Khatere; Temsch, Eva M; Leitch, Andrew R; Weiss-Schneeweiss, Hanna

    2018-01-01

    Polyploidy is a major driving force in angiosperm evolution, but our understanding of establishment and early diversification processes following allo- vs. auto-polyploidy is limited. An excellent system to address such questions is the monocot plant Prospero autumnale , as it comprises several genomically and chromosomally distinct diploid cytotypes and their auto- and allotetraploid derivatives. To infer origins and evolutionary trajectories of the tetraploids, we use genome size data, in situ hybridization with parental genomic DNAs and specific probes (satDNA, rDNAs), as well as molecular-phylogenetic analyses. Thus, we demonstrate that an astounding range of allotetraploid lineages has been formed recurrently by chromosomal re-patterning, interactions of chromosomally variable parental genomes and nested cycles of extensive hybridization, whereas autotetraploids have originated at least twice and are cytologically stable. During the recurrent formation and establishment across wide geographic areas hybridization in some populations could have inhibited lineage diversification and nascent speciation of such a hybrid swarm. However, cytotypes that became fixed in populations enhanced the potential for species diversification, possibly exploiting the extended allelic base, and fixed heterozygosity that polyploidy confers. The time required for polyploid cytotype fixation may in part reflect the lag phase reported for polyploids between their formation and species diversification.

  18. Multiple Origins and Nested Cycles of Hybridization Result in High Tetraploid Diversity in the Monocot Prospero

    Directory of Open Access Journals (Sweden)

    Tae-Soo Jang

    2018-04-01

    Full Text Available Polyploidy is a major driving force in angiosperm evolution, but our understanding of establishment and early diversification processes following allo- vs. auto-polyploidy is limited. An excellent system to address such questions is the monocot plant Prospero autumnale, as it comprises several genomically and chromosomally distinct diploid cytotypes and their auto- and allotetraploid derivatives. To infer origins and evolutionary trajectories of the tetraploids, we use genome size data, in situ hybridization with parental genomic DNAs and specific probes (satDNA, rDNAs, as well as molecular-phylogenetic analyses. Thus, we demonstrate that an astounding range of allotetraploid lineages has been formed recurrently by chromosomal re-patterning, interactions of chromosomally variable parental genomes and nested cycles of extensive hybridization, whereas autotetraploids have originated at least twice and are cytologically stable. During the recurrent formation and establishment across wide geographic areas hybridization in some populations could have inhibited lineage diversification and nascent speciation of such a hybrid swarm. However, cytotypes that became fixed in populations enhanced the potential for species diversification, possibly exploiting the extended allelic base, and fixed heterozygosity that polyploidy confers. The time required for polyploid cytotype fixation may in part reflect the lag phase reported for polyploids between their formation and species diversification.

  19. Genomic analysis of NAC transcription factors in banana (Musa acuminata) and definition of NAC orthologous groups for monocots and dicots.

    Science.gov (United States)

    Cenci, Albero; Guignon, Valentin; Roux, Nicolas; Rouard, Mathieu

    2014-05-01

    Identifying the molecular mechanisms underlying tolerance to abiotic stresses is important in crop breeding. A comprehensive understanding of the gene families associated with drought tolerance is therefore highly relevant. NAC transcription factors form a large plant-specific gene family involved in the regulation of tissue development and responses to biotic and abiotic stresses. The main goal of this study was to set up a framework of orthologous groups determined by an expert sequence comparison of NAC genes from both monocots and dicots. In order to clarify the orthologous relationships among NAC genes of different species, we performed an in-depth comparative study of four divergent taxa, in dicots and monocots, whose genomes have already been completely sequenced: Arabidopsis thaliana, Vitis vinifera, Musa acuminata and Oryza sativa. Due to independent evolution, NAC copy number is highly variable in these plant genomes. Based on an expert NAC sequence comparison, we propose forty orthologous groups of NAC sequences that were probably derived from an ancestor gene present in the most recent common ancestor of dicots and monocots. These orthologous groups provide a curated resource for large-scale protein sequence annotation of NAC transcription factors. The established orthology relationships also provide a useful reference for NAC function studies in newly sequenced genomes such as M. acuminata and other plant species.

  20. Submersible Data (Dive Trackpoints) for Life on the Edge 2004 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link I along its track during twenty-five dives of the 2004 "Life on the Edge" expedition sponsored by...

  1. Submersible Data (Dive Waypoints) for Investigating the Charleston Bump 2003 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link II at waypoints along its track during fourteen dives of the 2003 "Investigating the Charleston...

  2. Submersible Data (Dive Trackpoints) for Operation Deep Scope 2005 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link I along its track during thirteen dives of the 2005 "Operation Deep Scope" expedition sponsored by...

  3. Submersible Data (Dive Waypoints) for Bioluminescence 2009 - Office of Ocean Exploration and Research

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link II at waypoints along its track during seventeen dives of the 2009 "Bioluminescence" expedition...

  4. Submersion criticality safety of tungsten-rhenium urania cermet fuel for space propulsion and power applications

    Energy Technology Data Exchange (ETDEWEB)

    Craft, A.E., E-mail: aaron.craft@inl.gov [Center for Space Nuclear Research (CSNR), INL, Idaho Falls, ID (United States); O’Brien, R.C., E-mail: Robert.OBrien@inl.gov [Center for Space Nuclear Research (CSNR), INL, Idaho Falls, ID (United States); Howe, S.D., E-mail: Steven.Howe@inl.gov [Center for Space Nuclear Research (CSNR), INL, Idaho Falls, ID (United States); King, J.C., E-mail: kingjc@mines.edu [Nuclear Science and Engineering Program, Metallurgical and Materials Engineering Department, Colorado School of Mines, Golden, CO 80401 (United States)

    2014-07-01

    Highlights: • Criticality safety studies consider a generic space nuclear reactor in reentry scenarios. • Describes the submersion criticality behavior for a reactor fueled with a tungsten cermet fuel. • Study considers effects of varying fuel content, geometry, and other conditions. - Abstract: Nuclear thermal rockets are the preferred propulsion technology for a manned mission to Mars, and tungsten–uranium oxide cermet fuels could provide significant performance and cost advantages for nuclear thermal rockets. A nuclear reactor intended for use in space must remain subcritical before and during launch, and must remain subcritical in launch abort scenarios where the reactor falls back to Earth and becomes submerged in terrestrial materials (including seawater, wet sand, or dry sand). Submersion increases reflection of neutrons and also thermalizes the neutron spectrum, which typically increases the reactivity of the core. This effect is typically very significant for compact, fast-spectrum reactors. This paper provides a submersion criticality safety analysis for a representative tungsten/uranium oxide fueled reactor with a range of fuel compositions. Each submersion case considers both the rhenium content in the matrix alloy and the uranium oxide volume fraction in the cermet. The inclusion of rhenium significantly improves the submersion criticality safety of the reactor. While increased uranium oxide content increases the reactivity of the core, it does not significantly affect the submersion behavior of the reactor. There is no significant difference in submersion behavior between reactors with rhenium distributed within the cermet matrix and reactors with a rhenium clad in the coolant channels. The combination of the flooding of the coolant channels in submersion scenarios and the presence of a significant amount of spectral shift absorbers (i.e. high rhenium concentration) further decreases reactivity for short reactor cores compared to longer cores.

  5. Submersion-Subcritical Safe Space (S4) reactor

    International Nuclear Information System (INIS)

    King, Jeffrey C.; El-Genk, Mohamed S.

    2006-01-01

    The Submersion-Subcritical Safe Space (S 4 ) reactor, developed for future space power applications and avoidance of single point failures, is presented. The S 4 reactor has a Mo-14% Re solid core, loaded with uranium nitride fuel, cooled by He-30% Xe and sized to provide 550 kWth for 7 years of equivalent full power operation. The beryllium oxide reflector of the S 4 reactor is designed to completely disassemble upon impact on water or soil. The potential of using Spectral Shift Absorber (SSA) materials in different forms to ensure that the reactor remains subcritical in the worst-case submersion accident is investigated. Nine potential SSAs are considered in terms of their effect on the thickness of the radial reflector and on the combined mass of the reactor and the radiation shadow shield. The SSA materials are incorporated as a thin (0.1 mm) coating on the outside surface of the reactor core and as core additions in three possible forms: 2.0 mm diameter pins in the interstices of the core block, 0.25 mm thick sleeves around the fuel stacks and/or additions to the uranium nitride fuel. Results show that with a boron carbide coating and 0.25 mm iridium sleeves around the fuel stacks the S 4 reactor has a reflector outer diameter of 43.5 cm with a combined reactor and shadow shield mass of 935.1 kg. The S 4 reactor with 12.5 at.% gadolinium-155 added to the fuel, 2.0 mm diameter gadolinium-155 sesquioxide interstitial pins, and a 0.1 mm thick gadolinium-155 sesquioxide coating has a slightly smaller reflector outer diameter of 43.0 cm, resulting in a smaller total reactor and shield mass of 901.7 kg. With 8.0 at.% europium-151 added to the fuel, along with europium-151 sesquioxide for the pins and coating, the reflector's outer diameter and the total reactor and shield mass are further reduced to 41.5 cm and 869.2 kg, respectively

  6. Cercosporoid fungi (Mycosphaerellaceae) 2. Species on monocots (Acoraceae to Xyridaceae, excluding Poaceae).

    Science.gov (United States)

    Braun, Uwe; Crous, Pedro W; Nakashima, Chiharu

    2014-12-01

    Cercosporoid fungi (formerly Cercospora s. lat.) represent one of the largest groups of hyphomycetes belonging to the Mycosphaerellaceae (Ascomycota). They include asexual morphs, asexual holomorphs, or species with mycosphaerella-like sexual morphs. Most of them are leaf-spotting plant pathogens with special phytopathological relevance. In the first part of a new monographic work, cercosporoid hyphomycetes occurring on other fungi (fungicolous species), on ferns (pteridophytes) and gymnosperms were treated. This second part deals with cercosporoid fungi on monocots (Liliopsida; Equisetopsida, Magnoliidae, Lilianae), which covers species occurring on host plants belonging to families arranged in alphabetical order from Acoraceae to Xyridaceae, excluding Poaceae (cereals and grasses) which requires a separate treatment. The species are described and illustrated in alphabetical order under the particular cercosporoid genera, supplemented by keys to the species concerned. A detailed introduction, a survey of currently recognised cercosporoid genera, a key to the genera concerned, and a discussion of taxonomically relevant characters were published in the first part of this series. Neopseudocercospora, an additional recently introduced cercosporoid genus, is briefly discussed. The following taxonomic novelties are introduced: Cercospora alpiniigena sp. nov., C. neomaricae sp. nov., Corynespora palmicola comb. nov., Exosporium miyakei comb. nov., E. petersii comb. nov., Neopseudocercospora zambiensis comb. nov., Passalora caladiicola comb. nov., P. streptopi comb. nov., P. togashiana comb. nov., P. tranzschelii var. chinensis var. nov., Pseudocercospora beaucarneae comb. nov., P. constrictoflexuosa comb. et stat. nov., P. curcumicola sp. nov., P. dispori comb. nov., P. smilacicola sp. nov., P. urariigena nom. nov., Zasmidium agavicola comb. nov., Z. cercestidis-afzelii comb. nov., Z. citri-griseum comb. nov., Z. cyrtopodii comb. nov., Z. gahnae comb. nov., Z. indicum

  7. The plastid genome of Najas flexilis: adaptation to submersed environments is accompanied by the complete loss of the NDH complex in an aquatic angiosperm.

    Directory of Open Access Journals (Sweden)

    Elena L Peredo

    Full Text Available The re-colonization of aquatic habitats by angiosperms has presented a difficult challenge to plants whose long evolutionary history primarily reflects adaptations to terrestrial conditions. Many aquatics must complete vital stages of their life cycle on the water surface by means of floating or emergent leaves and flowers. Only a few species, mainly within the order Alismatales, are able to complete all aspects of their life cycle including pollination, entirely underwater. Water-pollinated Alismatales include seagrasses and water nymphs (Najas, the latter being the only freshwater genus in the family Hydrocharitaceae with subsurface water-pollination. We have determined the complete nucleotide sequence of the plastid genome of Najas flexilis. The plastid genome of N. flexilis is a circular AT-rich DNA molecule of 156 kb, which displays a quadripartite structure with two inverted repeats (IR separating the large single copy (LSC from the small single copy (SSC regions. In N. flexilis, as in other Alismatales, the rps19 and trnH genes are localized in the LSC region instead of within the IR regions as in other monocots. However, the N. flexilis plastid genome presents some anomalous modifications. The size of the SSC region is only one third of that reported for closely related species. The number of genes in the plastid is considerably less. Both features are due to loss of the eleven ndh genes in the Najas flexilis plastid. In angiosperms, the absence of ndh genes has been related mainly to the loss of photosynthetic function in parasitic plants. The ndh genes encode the NAD(PH dehydrogenase complex, believed essential in terrestrial environments, where it increases photosynthetic efficiency in variable light intensities. The modified structure of the N. flexilis plastid genome suggests that adaptation to submersed environments, where light is scarce, has involved the loss of the NDH complex in at least some photosynthetic angiosperms.

  8. Life extension of semi-submersible drilling unit

    Energy Technology Data Exchange (ETDEWEB)

    Hadley, I.; Sinclair, C.I.K. [TWI, Cambridge (United Kingdom). Structural Integrity Dept.; Magne, E. [Schlumberger Sedco Forex, Montrouge (France)

    1995-12-31

    This paper describes the life extension of a semi-submersible drilling rig built in the early 1970`s. A nominal design life of 20 years was estimated at the time of building; however, in the interim period, numerous improvements have been made in fatigue life estimation ad life improvement techniques, raising the possibility that a further 20 years of operation could be considered. The life extension strategy made use of a number of aspects of offshore technology which were not available at the time of construction of the rig. Finite element studies and results from offshore research programs were used to gauge the effect of fatigue life improvement techniques. The program demonstrated the feasibility of extending the operation of the rig for a further 20 years, with the interval between in-service inspection increased to every five years. It also provided a valuable database of fracture toughness data for the rig materials, which may be used in future work to address reliability issues.

  9. Commercial Submersible Mixing Pump For SRS Tank Waste Removal - 15223

    International Nuclear Information System (INIS)

    Hubbard, Mike; Herbert, James E.; Scheele, Patrick W.

    2015-01-01

    The Savannah River Site Tank Farms have 45 active underground waste tanks used to store and process nuclear waste materials. There are 4 different tank types, ranging in capacity from 2839 m 3 to 4921 m 3 (750,000 to 1,300,000 gallons). Eighteen of the tanks are older style and do not meet all current federal standards for secondary containment. The older style tanks are the initial focus of waste removal efforts for tank closure and are referred to as closure tanks. Of the original 51 underground waste tanks, six of the original 24 older style tanks have completed waste removal and are filled with grout. The insoluble waste fraction that resides within most waste tanks at SRS requires vigorous agitation to suspend the solids within the waste liquid in order to transfer this material for eventual processing into glass filled canisters at the Defense Waste Processing Facility (DWPF). SRS suspends the solid waste by use of recirculating mixing pumps. Older style tanks generally have limited riser openings which will not support larger mixing pumps, since the riser access is typically 58.4 cm (23 inches) in diameter. Agitation for these tanks has been provided by four long shafted standard slurry pumps (SLP) powered by an above tank 112KW (150 HP) electric motor. The pump shaft is lubricated and cooled in a pressurized water column that is sealed from the surrounding waste in the tank. Closure of four waste tanks has been accomplished utilizing long shafted pump technology combined with heel removal using multiple technologies. Newer style waste tanks at SRS have larger riser openings, allowing the processing of waste solids to be accomplished with four large diameter SLPs equipped with 224KW (300 HP) motors. These tanks are used to process the waste from closure tanks for DWPF. In addition to the SLPs, a 224KW (300 HP) submersible mixer pump (SMP) has also been developed and deployed within older style tanks. The SMPs are product cooled and product lubricated canned

  10. Commercial Submersible Mixing Pump For SRS Tank Waste Removal - 15223

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard, Mike [Savannah River Remediation, LLC., Aiken, SC (United States); Herbert, James E. [Savannah River Remediation, LLC., Aiken, SC (United States); Scheele, Patrick W. [Savannah River Remediation, LLC., Aiken, SC (United States)

    2015-01-12

    The Savannah River Site Tank Farms have 45 active underground waste tanks used to store and process nuclear waste materials. There are 4 different tank types, ranging in capacity from 2839 m3 to 4921 m3 (750,000 to 1,300,000 gallons). Eighteen of the tanks are older style and do not meet all current federal standards for secondary containment. The older style tanks are the initial focus of waste removal efforts for tank closure and are referred to as closure tanks. Of the original 51 underground waste tanks, six of the original 24 older style tanks have completed waste removal and are filled with grout. The insoluble waste fraction that resides within most waste tanks at SRS requires vigorous agitation to suspend the solids within the waste liquid in order to transfer this material for eventual processing into glass filled canisters at the Defense Waste Processing Facility (DWPF). SRS suspends the solid waste by use of recirculating mixing pumps. Older style tanks generally have limited riser openings which will not support larger mixing pumps, since the riser access is typically 58.4 cm (23 inches) in diameter. Agitation for these tanks has been provided by four long shafted standard slurry pumps (SLP) powered by an above tank 112KW (150 HP) electric motor. The pump shaft is lubricated and cooled in a pressurized water column that is sealed from the surrounding waste in the tank. Closure of four waste tanks has been accomplished utilizing long shafted pump technology combined with heel removal using multiple technologies. Newer style waste tanks at SRS have larger riser openings, allowing the processing of waste solids to be accomplished with four large diameter SLPs equipped with 224KW (300 HP) motors. These tanks are used to process the waste from closure tanks for DWPF. In addition to the SLPs, a 224KW (300 HP) submersible mixer pump (SMP) has also been developed and deployed within older style tanks. The SMPs are product cooled and

  11. Enhancement of innate immune system in monocot rice by transferring the dicotyledonous elongation factor Tu receptor EFR

    Institute of Scientific and Technical Information of China (English)

    Fen Lu; Huiqin Wang; Shanzhi Wang; Wendi Jiang; Changlin Shan; Bin Li; Jun Yang; Shiyong Zhang; Wenxian Sun

    2015-01-01

    The elongation factor Tu (EF-Tu) receptor (EFR) in cruciferous plants specifical y recognizes the N-terminal acetylated elf18 region of bacterial EF-Tu and thereby activates plant immunity. It has been demonstrated that Arabidopsis EFR confers broad-spectrum bacterial resistance in the EFR transgenic solanaceous plants. Here, the transgenic rice plants (Oryza sativa L. ssp. japonica cv. Zhonghua 17) and cel cultures with constitutive expression of AtEFR were developed to investigate whether AtEFR senses EF-Tu and thus enhances bacterial resistance in the monocot plants. We demonstrated that the Xanthomonas oryzae-derived elf18 peptide induced oxidative burst and mitogen-activated protein kinase activa-tion in the AtEFR transgenic rice cel s and plants, respectively. Pathogenesis-related genes, such as OsPBZ1, were upregulated dramatical y in transgenic rice plant and cel lines in response to elf18 stimulation. Importantly, pretreatment with elf18 trig-gered strong resistance to X. oryzae pv. oryzae in the transgenic plants, which was largely dependent on the AtEFR expression level. These plants also exhibited enhanced resistance to rice bacterial brown stripe, but not to rice fungal blast. Col ectively, the results indicate that the rice plants with heterologous expression of AtEFR recognize bacterial EF-Tu and exhibit enhanced broad-spectrum bacterial disease resistance and that pattern recognition receptor-mediated immunity may be manipulated across the two plant classes, dicots and monocots.

  12. Research and application of key technology of electric submersible plunger pump

    Science.gov (United States)

    Qian, K.; Sun, Y. N.; Zheng, S.; Du, W. S.; Li, J. N.; Pei, G. Z.; Gao, Y.; Wu, N.

    2018-06-01

    Electric submersible plunger pump is a new generation of rodless oil production equipment, whose improvements and upgrades of key technologies are conducive to its large-scale application and reduce the cost and improve the efficiency. In this paper, the operating mechanism of the unit in-depth study, aimed at the problems existing in oilfield production, to propose an optimization method creatively, including the optimal design of a linear motor for submersible oil, development of new double-acting load-relief pump, embedded flexible closed-loop control technology, research and development of low-cost power cables. 90 oil wells were used on field application, the average pump inspection cycle is 608 days, the longest pump check cycle has exceeded 1037 days, the average power saving rate is 45.6%. Application results show that the new technology of optimization and upgrading can further improve the reliability and adaptability of electric submersible plunger pump, reduce the cost of investment.

  13. New Navigation Post-Processing Tools for Oceanographic Submersibles

    Science.gov (United States)

    Kinsey, J. C.; Whitcomb, L. L.; Yoerger, D. R.; Howland, J. C.; Ferrini, V. L.; Hegrenas, O.

    2006-12-01

    We report the development of Navproc, a new set of software tools for post-processing oceanographic submersible navigation data that exploits previously reported improvements in navigation sensing and estimation (e.g. Eos Trans. AGU, 84(46), Fall Meet. Suppl., Abstract OS32A- 0225, 2003). The development of these tools is motivated by the need to have post-processing software that allows users to compensate for errors in vehicle navigation, recompute the vehicle position, and then save the results for use with quantitative science data (e.g. bathymetric sonar data) obtained during the mission. Navproc does not provide real-time navigation or display of data nor is it capable of high-resolution, three dimensional (3D) data display. Navproc supports the ASCII data formats employed by the vehicles of the National Deep Submergence Facility (NDSF) operated by the Woods Hole Oceanographic Institution (WHOI). Post-processing of navigation data with Navproc is comprised of three tasks. First, data is converted from the logged ASCII file to a binary Matlab file. When loaded into Matlab, each sensor has a data structure containing the time stamped data sampled at the native update rate of the sensor. An additional structure contains the real-time vehicle navigation data. Second, the data can be displayed using a Graphical User Interface (GUI), allowing users to visually inspect the quality of the data and graphically extract portions of the data. Third, users can compensate for errors in the real-time vehicle navigation. Corrections include: (i) manual filtering and median filtering of long baseline (LBL) ranges; (ii) estimation of the Doppler/gyro alignment using previously reported methodologies; and (iii) sound velocity, tide, and LBL transponder corrections. Using these corrections, the Doppler and LBL positions can be recomputed to provide improved estimates of the vehicle position compared to those computed in real-time. The data can be saved in either binary or ASCII

  14. Self-Propelled Semi-Submersibles: The Next Great Threat to Regional Security and Stability

    Science.gov (United States)

    2011-06-01

    December.27 The FARC is also coordinating with Chinese gangs in the tri-border area of Argentina, Paraguay and Brazil .28 These gangs could... mangrove swamps in Western Colombia you can be ten feet away from where somebody‘s building a semi-submersible and never see it.‖63 D. INSPECTION OF

  15. Effects of four fungicides on nine non-target submersed macrophytes

    NARCIS (Netherlands)

    Belgers, J.D.M.; Aalderink, G.H.; Brink, van den P.J.

    2009-01-01

    We tested the sensitivity of nine submersed macrophyte species to the fungicides chlorothalonil, pentachlorophenol, fluazinam, and carbendazim. Endpoints determined 3 weeks after the start of the treatment were based on shoot and root growth in water. Carbendazim proved not or only moderately toxic

  16. Competition between two submersed aquatic macrophytes, Potamogeton pectinatus and Potamogeton gramineus, across a light gradient

    Science.gov (United States)

    Submersed aquatic macrophyte communities, are often limited by the availability of light. Thus, they offer a unique opportunity to evaluate competition when light is the limiting resource. Competitive abilities of Potamogeton pectinatus (L.) Börner and Potamogeton gramineus L. were estimated using a...

  17. Geology of mud volcanos in the Eastern Mediterranean from combined sidescan and submersible surveys

    NARCIS (Netherlands)

    Zitter, T.A.C.; Huguen, C.; Woodside, J.M.

    2005-01-01

    Submersible observations and seafloor mapping over areas of mud volcanism in the eastern Mediterranean Sea reveal an abundance of methane-rich fluid emissions, as well as specific seep-associated fauna (e.g. tubeworms, bivalves and chemosynthetic bacteria) and diagenetic deposits (i.e. carbonates

  18. Nuevas citas de monocotiledóneas adventicias para la Argentina New records of adventitious monocots for Argentina

    Directory of Open Access Journals (Sweden)

    Julio A. Hurrell

    2009-12-01

    Full Text Available Este trabajo incluye cinco nuevos registros de monocotiledóneas adventicias para la Argentina: Aloe ciliaris Haw. (Asphodelaceae, Aspidistra elatior Blume (Convallariaceae, Sansevieria trifasciata Prain (Dracaenaceae, Phormium tenax J. R. Forst. & G. Forst. (Hemerocallidaceae y Ornithogalum arabicum L. (Hyacinthaceae, pertenecientes al orden Asparagales. También incluye una evaluación del estado actual de estas especies, en relación al proceso de naturalización: escapadas de cultivo ocasionales, naturalizadas.This paper includes five new records of adventitious monocots for Argentina: Aloe ciliaris Haw. (Asphodelaceae, Aspidistra elatior Blume (Convallariaceae, Sansevieria trifasciata Prain (Dracaenaceae, Phormium tenax J. R. Forst. & G. Forst. (Hemerocallidaceae and Ornithogalum arabicum L. (Hyacinthaceae, belonging to order Asparagales. Also includes an evaluation of its status in the naturalization process: casual alien, naturalized.

  19. Lumichrome and riboflavin are two novel symbiotic signals eliciting developmental changes in both monocot and dicot plant species

    Directory of Open Access Journals (Sweden)

    Felix Dapare Dakora

    2015-09-01

    Full Text Available Lumichrome and riboflavin are novel molecules from rhizobial exudates that stimulate plant growth. Developmental changes elicited by lumichrome at very low nanomolar concentrations (5 nM include early initiation of trifoliate leaves, expansion of unifoliate and trifoliate leaves, increased stem elongation and leaf area, and consequently greater biomass accumulation in monocots and dicots. However, higher lumichrome concentration (50 nM depressed root development and reduced growth of unifoliate and second trifoliate leaves. Applying either 10 nM lumichrome, 10 nM ABA, or 10 ml of infective rhizobial cells (0.2 OD600 to roots of monocots and dicots for 44 h produced identical effects, which included decreased stomatal conductance and leaf transpiration in Bambara groundnut, soybean and maize, increased stomatal conductance and transpiration in cowpea and lupin, and elevated root respiration in maize (19% by rhizobia and 20% by lumichrome. Extracellular exudation of lumichrome, riboflavin and IAA was greater in N2-fixing rhizobia than non-fixing bacteria, indicating their role as symbiotic signals. Xylem concentration of lumichrome in cowpea and soybean was greater in plants inoculated with infective rhizobia and treated with lumichrome (61.2 µmol lumichrome.ml-1 sap, followed by uninoculated plants receiving lumichrome (41.12 µmol lumichrome.ml-1 sap, and lowest in uninoculated, lumichrome-free plants (26.8 µmol lumichrome.ml-1 sap. Overall, soybean showed greater xylem concentration of lumichrome and a correspondingly increased accumulation in leaves relative to cowpea. As a result, soybean exhibited dramatic developmental changes than cowpea. Taken together, lumichrome and riboflavin secreted by soil rhizobia function as environmental cues for sensing stress. The fact that exogenous application of ABA to plant roots caused the same effect as lumichrome on stomatal functioning suggests molecular cross-talk in plant response to environmental

  20. Remelting of Aluminium by Continuous Submersion of Rolled Scrap

    Energy Technology Data Exchange (ETDEWEB)

    Farner, Snorre

    2000-12-01

    When remelting aluminium scrap, metal losses due to dross generation is a common problem. Reduction of these losses will give substantial economic and environmental benefits. Dross is generated when aluminium metal oxidizes and films of oxide envelope molten metal. When a cold metal object is immersed in a melt, the heat of the melt around this is transferred so rapidly into the object that a shell of melt often solidifies to the surface of the object. When scrap with low bulk density is charged to a melt, solidification of melt on the cold scrap prevents melt from entering the cavities in the bulk of the scrap, and the bulk density remains low. Thus the scrap tends to float on the melt surface. Submersion of this scrap is important to avoid oxidation and subsequent dross generation. One solution to this is to roll scrap to a strip and feed it into the melt. This system has been examined by studying feeding of a continuous, thin aluminium plate into molten aluminium. Also, the effect of lacquer was considered, as well as feeding the plate into a launder with melt flowing along the surface of the plate. An analytical, one-dimensional, steady-state model has been developed to describe the melting and the melting mechanisms. It is based on a shell solidifying on the plate surface and a gap introducing a thermal resistance 1/h{sub g} between the shell and the plate. The thermal resistance 1/h{sub l} of the boundary layer of the melt is included. Depending on these resistances, the initial temperature of the plate and the melt temperature, a shell will form, and the plate will penetrate a distance P into the melt before it melts away. An experimental apparatus was designed and constructed to feed aluminium plate from a coil into a melt bath at a specified velocity. The plate could be withdrawn rapidly to ''freeze'' the situation like it was below the melt surface. The penetration depth P of the plate could be measured and shell formation observed

  1. Submersible Data (Dive Waypoints) for Islands in the Stream 2002 - Deep Reef Habitat - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link II at waypoints along its track during one dive of the 2002 "Islands in the Stream - Deep Reef...

  2. vid113_0401p -- Point coverage of sediment types from video collected from the Delta submersible vehicle.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Delta submersible vehicle, outfitted with video equipment (and other devices), was deployed from theR/V Auriga during September 2001 to monitor seafloor...

  3. vid119_0601d -- Line coverage of sediment types from video collected from the Delta submersible vehicle.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Delta submersible vehicle, outfitted with video equipment (and other devices), was deployed from the R/V Auriga during September 2001 to monitor seafloor...

  4. vid119_0601c-- Point coverage of sediment types from video collected from the Delta submersible vehicle.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Delta submersible vehicle, outfitted with video equipment (and other devices), was deployed from the R/V Auriga during September 2001 to monitor seafloor...

  5. Modeling the Impacts of Suspended Sediment Concentration and Current Velocity on Submersed Vegetation in an Illinois River Pool, USA

    National Research Council Canada - National Science Library

    Best, Elly

    2004-01-01

    This technical note uses a modeling approach to examine the impacts of suspended sediment concentrations and current velocity on the persistence of submersed macrophytes in a shallow aquatic system...

  6. Submersible Data (Dive Waypoints) for Life on the Edge 2003: Exploring Deep Ocean Habitats - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link II at waypoints along its track during two of the seventeen dives of the 2003 "Life on the Edge -...

  7. Submersible Data (Dive Waypoints) for Islands in the Stream 2002 - Pharmaceutical Discovery, Vision, and Bioluminescence - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link II at waypoints along its track during one dive of the 2002 "Islands in the Stream -...

  8. Influence of temperature and salinity on heavy metal uptake by submersed plants

    Energy Technology Data Exchange (ETDEWEB)

    Fritioff, A. [Department of Botany, Stockholm University, S-106 91 Stockholm (Sweden)]. E-mail: fritioff@botan.su.se; Kautsky, L. [Department of Botany, Stockholm University, S-106 91 Stockholm (Sweden); Greger, M. [Department of Botany, Stockholm University, S-106 91 Stockholm (Sweden)

    2005-01-01

    Submersed plants can be useful in reducing heavy metal concentrations in stormwater, since they can accumulate large amounts of heavy metals in their shoots. To investigate the effects of water temperature and salinity on the metal uptake of two submersed plant species, Elodea canadensis (Michx.) and Potamogeton natans (L.), these plants were grown in the presence of Cu, Zn, Cd, and Pb at 5, 11, and 20 deg. C in combination with salinities of 0, 0.5, and 5%o. The metal concentrations in the plant tissue increased with increasing temperature in both species; the exception was the concentration of Pb in Elodea, which increased with decreasing salinity. Metal concentrations at high temperature or low salinity were up to twice those found at low temperature or high salinity. Plant biomass affected the metal uptake, with low biomass plants having higher metal concentrations than did high biomass plants. - Metal concentrations increase with increasing temperature and decreasing salinity in two aquatic plants.

  9. Influence of temperature and salinity on heavy metal uptake by submersed plants

    International Nuclear Information System (INIS)

    Fritioff, A.; Kautsky, L.; Greger, M.

    2005-01-01

    Submersed plants can be useful in reducing heavy metal concentrations in stormwater, since they can accumulate large amounts of heavy metals in their shoots. To investigate the effects of water temperature and salinity on the metal uptake of two submersed plant species, Elodea canadensis (Michx.) and Potamogeton natans (L.), these plants were grown in the presence of Cu, Zn, Cd, and Pb at 5, 11, and 20 deg. C in combination with salinities of 0, 0.5, and 5%o. The metal concentrations in the plant tissue increased with increasing temperature in both species; the exception was the concentration of Pb in Elodea, which increased with decreasing salinity. Metal concentrations at high temperature or low salinity were up to twice those found at low temperature or high salinity. Plant biomass affected the metal uptake, with low biomass plants having higher metal concentrations than did high biomass plants. - Metal concentrations increase with increasing temperature and decreasing salinity in two aquatic plants

  10. Concept of a nuclear powered submersible research vessel and a compact reactor

    International Nuclear Information System (INIS)

    Kusunoki, Tsuyoshi; Odano, Naoteru; Yoritsune, Tsutomu; Ishida, Toshihisa; Nishimura, Hajime; Tokunaga, Sango

    2001-07-01

    A conceptual design study of a submersible research vessel navigating in 600 m depth and a compact nuclear reactor were carried out for the expansion of the nuclear power utilization. The mission of the vessel is the research of mechanism of the climate change to predict the global environment. Through conditions of the Arctic Ocean and the sea at high latitude have significant impacts on the global environmental change, it is difficult to investigate those areas by ordinary ships because of thick ice or storm. Therefore the research vessel is mainly utilized in the Arctic Ocean and the sea at high latitude. By taking account of the research mission, the basic specifications of the vessel are decided; the total weight is 500 t, the submersible depth is 600 m, the maximum speed is 12 knots (22.2 km/h), and the number of crews is 16. Nuclear power has an advantage in supplying large power of electricity in the sea for long period. Based on the requirements, it has been decided that two sets of submersible compact reactor, SCR, which is light-weighted and of enhanced safety characteristics of supply the total electricity of 500 kW. (author)

  11. Structural variations among monocot emergent and amphibious species from lakes of the semi-arid region of Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    KRB Leite

    Full Text Available Temporary lakes are common in the semi-arid region of the State of Bahia and form water mirrors in the rainy season. In this period, various vegetal species appear having different life forms adapted to the seasonality conditions of the rainfall regime. This work surveyed the adaptive anatomical structures of some emergent and amphibious monocot species occurring in these lakes. We studied the anatomy of roots, rhizomes, leaves and scapes of Cyperus odoratus, Oxycaryum cubense, Pycreus macrostachyos (Cyperaceae - amphibious species; and of Echinodorus grandiflorus (Alismataceae, Eichhornia paniculata (Pontederiaceae and Habenaria repens (Orchidaceae - emergent species. The anatomical features of the dermal, fundamental and vascular systems confirming the tendency of the adaptive convergence of these plants to temporary lacustrine the environment include: single layered epidermal cells with a thin cuticle layer in the aerial organs; the presence of air canals in all the organs; few or no supporting tissues; and less numerous conducting elements and thinner cell walls in the xylem. The reduction of the supporting tissues, the number of stomata, which can even be absent, and the number of conducting elements and the degree of cell wall lignification in the xylem of the emergent species is more accentuated than that of the amphibious species. The pattern of distribution of aerenchyma in the roots of the studied species was considered important to distinguish between amphibious and emergent life forms.

  12. Structural variations among monocot emergent and amphibious species from lakes of the semi-arid region of Bahia, Brazil.

    Science.gov (United States)

    Leite, K R B; França, F; Scatena, V I

    2012-02-01

    Temporary lakes are common in the semi-arid region of the State of Bahia and form water mirrors in the rainy season. In this period, various vegetal species appear having different life forms adapted to the seasonality conditions of the rainfall regime. This work surveyed the adaptive anatomical structures of some emergent and amphibious monocot species occurring in these lakes. We studied the anatomy of roots, rhizomes, leaves and scapes of Cyperus odoratus, Oxycaryum cubense, Pycreus macrostachyos (Cyperaceae) - amphibious species; and of Echinodorus grandiflorus (Alismataceae), Eichhornia paniculata (Pontederiaceae) and Habenaria repens (Orchidaceae) - emergent species. The anatomical features of the dermal, fundamental and vascular systems confirming the tendency of the adaptive convergence of these plants to temporary lacustrine the environment include: single layered epidermal cells with a thin cuticle layer in the aerial organs; the presence of air canals in all the organs; few or no supporting tissues; and less numerous conducting elements and thinner cell walls in the xylem. The reduction of the supporting tissues, the number of stomata, which can even be absent, and the number of conducting elements and the degree of cell wall lignification in the xylem of the emergent species is more accentuated than that of the amphibious species. The pattern of distribution of aerenchyma in the roots of the studied species was considered important to distinguish between amphibious and emergent life forms.

  13. Calculation of conversion coefficients using Chinese adult reference phantoms for air submersion and ground contamination.

    Science.gov (United States)

    Lu, Wei; Qiu, Rui; Wu, Zhen; Li, Chunyan; Yang, Bo; Liu, Huan; Ren, Li; Li, Junli

    2017-03-21

    The effective and organ equivalent dose coefficients have been widely used to provide assessment of doses received by adult members of the public and by workers exposed to environmental radiation from nuclear facilities under normal or accidental situations. Advancements in phantom types, weighting factors, decay data, etc, have led to the publication of newer results in this regard. This paper presents a new set of conversion coefficients for air submersion and ground contamination (with the use of Geant4) for photons from 15 keV to 10 MeV using the Chinese and International Commission on Radiological Protection (ICRP) adult reference male and female phantoms. The radiation fields, except for energy spectrum at low energies, were validated by the data obtained from the Monte Carlo code YURI. The effective dose coefficients of monoenergetic photons, obtained for the ICRP adult reference phantoms, agree well with recently published data for air submersion and ground contamination with a plane source at a depth of 0.5 g cm -2 in soil, but an average difference of 36.5% is observed for ground surface contamination with the abovementioned radiation field. The average differences in organ equivalent dose coefficients between the Chinese and the ICRP adult reference phantoms are within 6% for most organs, but noticeable differences of up to 70% or even higher are found at photon energies below 30 keV under air submersion. The effective dose coefficients obtained with the Chinese adult reference phantoms are greater than those of the ICRP adult reference phantoms above 30 keV and 0.5 MeV for ground contamination and air submersion, respectively; the average differences from the Chinese adult reference phantoms are about 3.6% and 0.4% in the whole energy range with maximum differences of 31.8% and 27.6% at 15 keV for air submersion and ground contamination respectively. These differences are attributed to anatomical discrepancies in overlying tissue mass of an

  14. Arsenic, Zinc, and Aluminium Removal from Gold Mine Wastewater Effluents and Accumulation by Submerged Aquatic Plants (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata

    Directory of Open Access Journals (Sweden)

    Ahmad Farid Abu Bakar

    2013-01-01

    Full Text Available The potential of three submerged aquatic plant species (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata to be used for As, Al, and Zn phytoremediation was tested. The plants were exposed for 14 days under hydroponic conditions to mine waste water effluents in order to assess the suitability of the aquatic plants to remediate elevated multi-metals concentrations in mine waste water. The results show that the E. densa and H. verticillata are able to accumulate high amount of arsenic (95.2% and zinc (93.7% and resulted in a decrease of arsenic and zinc in the ambient water. On the other hand, C. piauhyensis shows remarkable aluminium accumulation in plant biomass (83.8% compared to the other tested plants. The ability of these plants to accumulate the studied metals and survive throughout the experiment demonstrates the potential of these plants to remediate metal enriched water especially for mine drainage effluent. Among the three tested aquatic plants, H. verticillata was found to be the most applicable (84.5% and suitable plant species to phytoremediate elevated metals and metalloid in mine related waste water.

  15. Temperature-dependent development, cold tolerance, and potential distribution of Cricotopus lebetis (Diptera: Chironomidae), a tip miner of Hydrilla verticillata (Hydrocharitaceae).

    Science.gov (United States)

    Stratman, Karen N; Overholt, William A; Cuda, James P; Mukherjee, A; Diaz, R; Netherland, Michael D; Wilson, Patrick C

    2014-10-15

    A chironomid midge, Cricotopus lebetis (Sublette) (Diptera: Chironomidae), was discovered attacking the apical meristems of Hydrilla verticillata (L.f. Royle) in Crystal River, Citrus Co., Florida in 1992. The larvae mine the stems of H. verticillata and cause basal branching and stunting of the plant. Temperature-dependent development, cold tolerance, and the potential distribution of the midge were investigated. The results of the temperature-dependent development study showed that optimal temperatures for larval development were between 20 and 30°C, and these data were used to construct a map of the potential number of generations per year of C. lebetis in Florida. Data from the cold tolerance study, in conjunction with historical weather data, were used to generate a predicted distribution of C. lebetis in the United States. A distribution was also predicted using an ecological niche modeling approach by characterizing the climate at locations where C. lebetis is known to occur and then finding other locations with similar climate. The distributions predicted using the two modeling approaches were not significantly different and suggested that much of the southeastern United States was climatically suitable for C. lebetis. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

  16. Arsenic, Zinc, and Aluminium Removal from Gold Mine Wastewater Effluents and Accumulation by Submerged Aquatic Plants (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata)

    Science.gov (United States)

    Yusoff, Ismail; Fatt, Ng Tham; Othman, Faridah; Ashraf, Muhammad Aqeel

    2013-01-01

    The potential of three submerged aquatic plant species (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata) to be used for As, Al, and Zn phytoremediation was tested. The plants were exposed for 14 days under hydroponic conditions to mine waste water effluents in order to assess the suitability of the aquatic plants to remediate elevated multi-metals concentrations in mine waste water. The results show that the E. densa and H. verticillata are able to accumulate high amount of arsenic (95.2%) and zinc (93.7%) and resulted in a decrease of arsenic and zinc in the ambient water. On the other hand, C. piauhyensis shows remarkable aluminium accumulation in plant biomass (83.8%) compared to the other tested plants. The ability of these plants to accumulate the studied metals and survive throughout the experiment demonstrates the potential of these plants to remediate metal enriched water especially for mine drainage effluent. Among the three tested aquatic plants, H. verticillata was found to be the most applicable (84.5%) and suitable plant species to phytoremediate elevated metals and metalloid in mine related waste water. PMID:24102060

  17. Analysis of Electric Propulsion Performance on Submersible with Motor DC, Supply Power 10260AH at Voltage 115VDC

    Directory of Open Access Journals (Sweden)

    Indra Ranu Kusuma

    2017-03-01

    Full Text Available Electric propulsion is the ship system using propulsion motor to replace performance of main engine. The application of diesel engine as propulsion system have some problems and weaknesses such as diesel engine unability to operate when submersible vessel is operating under sea. To overcome that problems in submersible vessel, alternative solution of ship propulsion is required. DC Motor can be used as this alternative solution. Submersible vessel use electric propulsion system with DC Motor because DC Motor has advantages of easy rotation setting and does not cause noise when submersible vessel is diving. This bachelor thesis will study the application of DC Motor as an electric propulsion system on submersible vessel with length 59,57 m in series and parallel circuit by simulation using MATLAB software. The simulation data obtained are rotation and torque of DC Motor. From these simulation, it can be concluded that parallel circuit rotation is greater than series circuit rotation. It caused the greater speed and lower power in parallel circuit. 

  18. Photosynthetic pigment concentrations, gas exchange and vegetative growth for selected monocots and dicots treated with two contrasting coal fly ashes

    Energy Technology Data Exchange (ETDEWEB)

    Yunusa, I.A.M.; Burchett, M.D.; Manoharan, V.; DeSilva, D.L.; Eamus, D.; Skilbeck, C.G. [University of Technology Sydney, Sydney, NSW (Australia). Dept. of Environmental Science

    2009-07-15

    There is uncertainty as to the rates of coal fly ash needed for optimum physiological processes and growth. In the current study we tested the hyothesis that photosynthetic pigments concentrations and CO{sub 2} assimilation (A) are more sensitive than dry weights in plants grown on media amended with coal fly ash. We applied the Terrestrial Plant Growth Test (Guideline 208) protocols of the Organization for Economic Cooperation and Development (OECD) to monocots (barley (Hordeum vulgare) and ryegrass (Secale cereale)) and dicots (canola (Brasica napus), radish (Raphanus sativus), field peas (Pisum sativum), and lucerne (Medicago sativa)) on media amended with fly ashes derived from semi-bituminous (gray ash) or lignite (red ash) coals at rates of 0, 2.5, 5.0, 10, or 20 Mg ha(-1). The red ash had higher elemental concentrations and salinity than the gray ash. Fly ash addition had no significant effect on germination by any of the six species. At moderate rates ({<=}10 Mg ha{sup -1}) both ashes increased (P < 0.05) growth rates and concentrations of chlorophylls a and b, but reduced carotenoid concentrations. Addition of either ash increased A in radish and transpiration in barley. Growth rates and final dry weights were reduced for all of the six test species when addition rates exceeded 10 Mg ha{sup -1} for gray ash and 5 Mg ha{sup -1} for red ash. We concluded that plant dry weights, rather than pigment concentrations and/or instantaneous rates of photosynthesis, are more consistent for assessing subsequent growth in plants supplied with fly ash.

  19. SULEU NTP Core with Passive Reactivity Control and Enhanced Submersion Safety

    Energy Technology Data Exchange (ETDEWEB)

    Venneri, Paolo; Kim, Yong Hee [KAIST, Daejeon (Korea, Republic of); Eades, Michael J [The Ohio State University, Ohio (United States)

    2016-05-15

    In this summary, SULEU has been adapted to implement some of the latest developments of LEUNTP design efforts. These include the implementation of a rapid depletion burnable absorber to flatten the reactivity profile during operation and the addition of a lower axial reflector to help minimize the reactivity increase during the full submersion criticality accident. The purpose of this study is to show the state of current LEU-NTP designs in terms of resolving key issues such as minimizing control drum usage and resolving the full submersion criticality accident. Future work will include integrating the rapid depletion poison with other passive reactivity control devices (such as hydrogen density in the tie-tubes) and developing additional systems for mitigating the full submersion criticality accident. It is widely acknowledged that nuclear thermal propulsion (NTP) is an enabling technology for manned missions to Mars and other locations beyond low-Earth orbit. Without nuclear thermal propulsion, manned space travel will be severely limited by the propellant requirements of chemical propulsion and significantly longer travel times of electric propulsion. While the performance superiority of NTP is clear, its implementation has been to date unsuccessful due to the significant costs of development, implementation, and regulations associated with the heritage NTP designs. These new systems take heritage designs and experimental results and adapt them to use LEU fuel with minimum impact on the heritage system. This is done in order to ensure their continued relevance with existing NTP research efforts and enable their rapid implementation into existing NASA efforts for human Mars mission planning. Of the current baseline NTP designs being studied, this paper concerns itself with the improvement of the Superb Use of Low Enriched (SULEU) core.

  20. Thermal effects of whole head submersion in cold water on nonshivering humans.

    Science.gov (United States)

    Pretorius, Thea; Bristow, Gerald K; Steinman, Alan M; Giesbrecht, Gordon G

    2006-08-01

    This study isolated the effect of whole head submersion in cold water, on surface heat loss and body core cooling, when the confounding effect of shivering heat production was pharmacologically eliminated. Eight healthy male subjects were studied in 17 degrees C water under four conditions: the body was either insulated or uninsulated, with the head either above the water or completely submersed in each body-insulation subcondition. Shivering was abolished with buspirone (30 mg) and meperidine (2.5 mg/kg), and subjects breathed compressed air throughout all trials. Over the first 30 min of immersion, exposure of the head increased core cooling both in the body-insulated conditions (head out: 0.47 +/- 0.2 degrees C, head in: 0.77 +/- 0.2 degrees C; P body-exposed conditions (head out: 0.84 +/- 0.2 degrees C and head in: 1.17 +/- 0.5 degrees C; P body surface area) in the body-exposed conditions increased total heat loss by only 10%. In both body-exposed and body-insulated conditions, head submersion increased core cooling rate much more (average of 42%) than it increased total heat loss. This may be explained by a redistribution of blood flow in response to stimulation of thermosensitive and/or trigeminal receptors in the scalp, neck and face, where a given amount of heat loss would have a greater cooling effect on a smaller perfused body mass. In 17 degrees C water, the head does not contribute relatively more than the rest of the body to surface heat loss; however, a cold-induced reduction of perfused body mass may allow this small increase in heat loss to cause a relatively larger cooling of the body core.

  1. Study on global performances and mooring-induced damping of a semi-submersible

    Science.gov (United States)

    Xiong, Ling-zhi; Yang, Jian-min; Lv, Hai-ning; Zhao, Wen-hua; Kou, Yu-feng

    2016-10-01

    The harsh environmental conditions bring strong nonlinearities to the hydrodynamic performances of the offshore floating platforms, which challenge the reliable prediction of the platform coupled with the mooring system. The present study investigates a typical semi-submersible under both the operational and the survival conditions through numerical and experimental methods. The motion responses, the mooring line tensions, and the wave loads on the longitudinal mid-section are investigated by both the fully non-linearly coupled numerical simulation and the physical experiment. Particularly, in the physical model test, the wave loads distributed on the semi-submersible's mid-section were measured by dividing the model into two parts, namely the port and the starboard parts, which were rigidly connected by three six-component force transducers. It is concluded that both the numerical and physical model can have good prediction of the semi-submersible's global responses. In addition, an improved numerical approach is proposed for the estimation of the mooring-induced damping, and is validated by both the experimental and the published results. The characteristics of the mooring-induced damping are further summarized in various sea states, including the operational and the survival environments. In order to obtain the better prediction of the system response in deep water, the mooring-induced damping of the truncated mooring lines applied in the physical experiment are compensated by comparing with those in full length. Furthermore, the upstream taut and the downstream slack mooring lines are classified and investigated to obtain the different mooring line damping performances in the comparative study.

  2. INTENSITY SETTER FOR A DEVICE OF SMOOTH START OF SUBMERSIBLE PUMP ELECTRIC MOTOR

    Directory of Open Access Journals (Sweden)

    V.I. Lobov

    2016-06-01

    Full Text Available Purpose. Development of an intensity setter, which in a rational law changes the opening thyristor the voltage regulator and effectively to changing power supply voltage stator windings of the electric pump deepening, ensuring a smooth start in a wide range. Methodology. Electric submersible pump belongs to the small inertia electric, since it is not significant total moment of inertia, not exceeding two moments of inertia of the motor and static moment on the shaft does not exceed forty percent of the nominal torque. For technical requirements that electric acceleration time should have no less than twenty seconds or more. Office starting modes of electric submersible pumps economically justified using thyristor voltage regulator by forming the dial changes the intensity of the necessary legislation in time voltage feeding the stator windings. This ensures a smooth start right rotor of the electric submersible pump. Results. A block diagram of the intensity setter that is: with control unit, two units that form the exponential voltage supply emitter follower and regulatory elements. The mathematical expressions for voltage at the stator windings of the motor, changing exponentially, opening the angle of thyristor power unit thyristor the voltage regulator, which is determined through the initial angle of opening. Provided formula for pick-up voltage and minimum voltage, time constants, which are determined from the basic equations of motion and mechanical characteristics of the electric motor. Analytical investigated by the voltage dependence violation by changing the time constant flowing and growing exhibitor supply voltage stator electric circuit deepening pump. Originality. Proposed in the initial time on the stator windings of the electric pick-up voltage is applied. Under the influence of this voltage, motor rotor begins to accelerate. At the same time, pick-up voltage decreases the minimum startup voltage varies exponentially in which

  3. Increased power generation from primary sludge by a submersible microbial fuel cell and optimum operational conditions

    DEFF Research Database (Denmark)

    Vologni, Valentina; Kakarla, Ramesh; Angelidaki, Irini

    2013-01-01

    Microbial fuel cells (MFCs) have received attention as a promising renewable energy technology for waste treatment and energy recovery. We tested a submersible MFC with an innovative design capable of generating a stable voltage of 0.250 ± 0.008 V (with a fixed 470 Ω resistor) directly from prima...... prolonged the current generation and increased the power density by 7 and 1.5 times, respectively, in comparison with raw primary sludge. These findings suggest that energy recovery from primary sludge can be maximized using an advanced MFC system with optimum conditions....

  4. Innovative self-powered submersible microbial electrolysis cell (SMEC) for biohydrogen production from anaerobic reactors

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2012-01-01

    A self-powered submersible microbial electrolysis cell (SMEC), in which a specially designed anode chamber and external electricity supply were not needed, was developed for in situ biohydrogen production from anaerobic reactors. In batch experiments, the hydrogen production rate reached 17.8 m...... improvement of voltage output and reduction of electron losses were essential for efficient hydrogen generation. In addition, alternate exchanging the electricity-assisting and hydrogen-producing function between the two cell units of the SMEC was found to be an effective approach to inhibit methanogens...

  5. Elaboración de abono orgánico a partir de plantas acuáticas: Elodea (Hydrilla verticillata) y Jacinto o Lirio de agua (Eichhornia crassipes), procedentes del Lago de Coatepeque y Lago de Güija

    OpenAIRE

    Reyes de Cabrales, Cecilia Elizabeth

    2009-01-01

    El presente estudio tiene por finalidad elaborar un abono orgánico bajo la técnica de compostaje, conocida como proceso de descomposición aeróbica. Se realizaron tres formulaciones de abono a partir de las plantas acuáticas Elodea (Hydrilla verticillata) y Jacinto de agua (Eichhornia crassipes) en las siguientes proporciones: Elodea 100%, Jacinto de agua 100% y mezcla de ambas en una proporción de 50:50. A los abonos obtenidos se les realizaron análisis químico con la finalidad de cuantificar...

  6. A Hydraulic Motor-Alternator System for Ocean-Submersible Vehicles

    Science.gov (United States)

    Aintablian, Harry O.; Valdez, Thomas I.; Jones, Jack A.

    2012-01-01

    An ocean-submersible vehicle has been developed at JPL that moves back and forth between sea level and a depth of a few hundred meters. A liquid volumetric change at a pressure of 70 bars is created by means of thermal phase change. During vehicle ascent, the phase-change material (PCM) is melted by the circulation of warm water and thus pressure is increased. During vehicle descent, the PCM is cooled resulting in reduced pressure. This pressure change is used to generate electric power by means of a hydraulic pump that drives a permanent magnet (PM) alternator. The output energy of the alternator is stored in a rechargeable battery that powers an on-board computer, instrumentation and other peripherals.The focus of this paper is the performance evaluation of a specific hydraulic motor-alternator system. Experimental and theoretical efficiency data of the hydraulic motor and the alternator are presented. The results are used to evaluate the optimization of the hydraulic motor-alternator system. The integrated submersible vehicle was successfully operated in the Pacific Ocean near Hawaii. A brief overview of the actual test results is presented.

  7. Mitigating with macrophytes: submersed plants reduce the toxicity of pesticide-contaminated water to zooplankton.

    Science.gov (United States)

    Brogan, William R; Relyea, Rick A

    2013-03-01

    In ecotoxicology, appreciation is growing for the influence that ecological interactions have on the toxicity of contaminants, such as insecticides, to sensitive species. Most previous studies, however, have focused on factors that exacerbate insecticide effects on species, while factors that may mitigate these effects have been relatively ignored. In aquatic habitats, a small number of studies have shown that submersed macrophytes can remove some insecticides from the water column via sorption. Although examining sorption dynamics is important for understanding the environmental fate of insecticides, whether and to what extent macrophytes actually mitigate insecticide effects on aquatic species remains unknown. In the present study, the authors examined how much and how quickly several realistic densities of the macrophyte Elodea canadensis decreased the toxicity of the insecticide malathion to Daphnia magna, a keystone aquatic herbivore. To do this, the authors quantified Daphnia survival in outdoor test systems (0.95 L) exposed to a factorial combination of five Elodea densities crossed with five malathion concentrations. The authors discovered that malathion's lethality to Daphnia decreased with increasing Elodea density. Furthermore, the rate at which Elodea reduced malathion's toxicity in the water column increased with macrophyte density. These results provide strong evidence that submersed macrophytes can mitigate the ecological impacts of a popular insecticide and further support that ecological interactions can strongly influence contaminant environmental effects. Copyright © 2013 SETAC.

  8. Submersible pumps: Energetic efficiency norm; Bombas sumergibles: norma de eficiencia energetica

    Energy Technology Data Exchange (ETDEWEB)

    Acosta Torres, R. A.; Buendia Dominguez, E. H. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    The Instituto de Investigaciones Electricas (IIE), supporting the Comision Nacional para el Ahorro de Energia (CONAE), has prepared a preliminary project of the norm of energy efficiency for submersible pumps. This document has complied with the necessary formalities for the emission of the norm. This paper presents the results of the analysis of the submersible pumps, the energy savings, as well as the economic evaluation that sustains the norm project, additionally pointing out the environmental impact that will bring along the implantation of the same. [Espanol] El Instituto de Investigaciones Electricas (IIE), apoyando a la Comision Nacional para el Ahorro de Energia (CONAE), ha elaborado el anteproyecto de norma de eficiencia energetica para bombas sumergibles. Dicho documento ha cumplido con los tramites necesarios para la emision de una norma. En el presente articulo se mencionan los resultados del analisis de las bombas sumergibles, los ahorros energeticos, asi como la evaluacion economica que sustenta el proyecto de norma, indicandose ademas el impacto ambiental que tendra la implantacion de la misma.

  9. Submersible pumps: Energetic efficiency norm; Bombas sumergibles: norma de eficiencia energetica

    Energy Technology Data Exchange (ETDEWEB)

    Acosta Torres, R A; Buendia Dominguez, E H [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-12-31

    The Instituto de Investigaciones Electricas (IIE), supporting the Comision Nacional para el Ahorro de Energia (CONAE), has prepared a preliminary project of the norm of energy efficiency for submersible pumps. This document has complied with the necessary formalities for the emission of the norm. This paper presents the results of the analysis of the submersible pumps, the energy savings, as well as the economic evaluation that sustains the norm project, additionally pointing out the environmental impact that will bring along the implantation of the same. [Espanol] El Instituto de Investigaciones Electricas (IIE), apoyando a la Comision Nacional para el Ahorro de Energia (CONAE), ha elaborado el anteproyecto de norma de eficiencia energetica para bombas sumergibles. Dicho documento ha cumplido con los tramites necesarios para la emision de una norma. En el presente articulo se mencionan los resultados del analisis de las bombas sumergibles, los ahorros energeticos, asi como la evaluacion economica que sustenta el proyecto de norma, indicandose ademas el impacto ambiental que tendra la implantacion de la misma.

  10. In Situ Detection of Macronutrients and Chloride in Seawater by Submersible Electrochemical Sensors.

    Science.gov (United States)

    Cuartero, Maria; Crespo, Gaston; Cherubini, Thomas; Pankratova, Nadezda; Confalonieri, Fabio; Massa, Francesco; Tercier-Waeber, Mary-Lou; Abdou, Melina; Schäfer, Jörg; Bakker, Eric

    2018-04-03

    A new submersible probe for the in situ detection of nitrate, nitrite, and chloride in seawater is presented. Inline coupling of a desalination unit, an acidification unit, and a sensing flow cell containing all-solid-state membrane electrodes allows for the potentiometric detection of nitrate and nitrite after removal of the key interfering ions in seawater, chloride and hydroxide. Thus, the electrodes exhibited attractive analytical performances for the potentiometric detection of nitrate and nitrite in desalinated and acidified seawater: fast response time ( t 95 macronutrient levels with salinity cycles, which is of special interest in recessed coastal water bodies. The system is capable of autonomous operation during deployment, with routines for repetitive measurements (every 2 h), data storage and management, and computer visualization of the data in real time. In situ temporal profiles observed in the Arcachon Bay (France) showed valuable environmental information concerning tide-dependent cycles of nitrate and chloride levels in the lagoon, which are here observed for the first time using direct in situ measurements. The submersible probe based on membrane electrodes presented herein may facilitate the study of biogeochemical processes occurring in marine ecosystems by the direct monitoring of nitrate and nitrite levels, which are key chemical targets in coastal waters.

  11. Microbial Biofilm Community Variation in Flowing Habitats: Potential Utility as Bioindicators of Postmortem Submersion Intervals

    Directory of Open Access Journals (Sweden)

    Jennifer M. Lang

    2016-01-01

    Full Text Available Biofilms are a ubiquitous formation of microbial communities found on surfaces in aqueous environments. These structures have been investigated as biomonitoring indicators for stream heath, and here were used for the potential use in forensic sciences. Biofilm successional development has been proposed as a method to determine the postmortem submersion interval (PMSI of remains because there are no standard methods for estimating the PMSI and biofilms are ubiquitous in aquatic habitats. We sought to compare the development of epinecrotic (biofilms on Sus scrofa domesticus carcasses and epilithic (biofilms on unglazed ceramic tiles communities in two small streams using bacterial automated ribosomal intergenic spacer analysis. Epinecrotic communities were significantly different from epilithic communities even though environmental factors associated with each stream location also had a significant influence on biofilm structure. All communities at both locations exhibited significant succession suggesting that changing communities throughout time is a general characteristic of stream biofilm communities. The implications resulting from this work are that epinecrotic communities have distinctive shifts at the first and second weeks, and therefore the potential to be used in forensic applications by associating successional changes with submersion time to estimate a PMSI. The influence of environmental factors, however, indicates the lack of a successional pattern with the same organisms and a focus on functional diversity may be more applicable in a forensic context.

  12. Phytotoxicity of atrazine, isoproturon, and diuron to submersed macrophytes in outdoor mesocosms

    International Nuclear Information System (INIS)

    Knauert, Stefanie; Singer, Heinz; Hollender, Juliane; Knauer, Katja

    2010-01-01

    The submersed macrophytes Elodea canadensis, Myriophyllum spicatum and Potamogeton lucens were constantly exposed over a five-week period to environmentally relevant concentrations of atrazine, isoproturon, diuron, and their mixture in outdoor mesocosms. Effects were evaluated investigating photosynthetic efficiency (PE) of the three macrophytes and growth of M. spicatum and E. canadensis. Adverse effects on PE were observed on days 2 and 5 after application. M. spicatum was found to be the more sensitive macrophyte. E. canadensis and P. lucens were less sensitive to atrazine, diuron and the mixture and insensitive to isoproturon. PE of M. spicatum was similarly affected by the single herbicides and the mixture demonstrating concentration addition. Growth of E. canadensis and M. spicatum was not reduced indicating that herbicide exposure did not impair plant development. Although PE measurements turned out to be a sensitive method to monitor PSII herbicides, plant growth remains the more relevant ecological endpoint in risk assessment. - Short-term effects on photosynthesis did not result in growth reduction of submerse macrophytes exposed to PSII inhibitors.

  13. Phytotoxicity of atrazine, isoproturon, and diuron to submersed macrophytes in outdoor mesocosms

    Energy Technology Data Exchange (ETDEWEB)

    Knauert, Stefanie, E-mail: stefanie.knauert@basf.co [University of Basel, Department of Environmental Sciences, Hebelstrasse 1, 4056 Basel (Switzerland); Singer, Heinz; Hollender, Juliane [Eawag: Swiss Federal Institute of Aquatic Science and Technology, Department of Environmental Chemistry, Uberlandstrasse 133, 8600 Duebendorf (Switzerland); Knauer, Katja [University of Basel, Program Sustainability Research, Klingelbergstr. 50, 4056 Basel (Switzerland)

    2010-01-15

    The submersed macrophytes Elodea canadensis, Myriophyllum spicatum and Potamogeton lucens were constantly exposed over a five-week period to environmentally relevant concentrations of atrazine, isoproturon, diuron, and their mixture in outdoor mesocosms. Effects were evaluated investigating photosynthetic efficiency (PE) of the three macrophytes and growth of M. spicatum and E. canadensis. Adverse effects on PE were observed on days 2 and 5 after application. M. spicatum was found to be the more sensitive macrophyte. E. canadensis and P. lucens were less sensitive to atrazine, diuron and the mixture and insensitive to isoproturon. PE of M. spicatum was similarly affected by the single herbicides and the mixture demonstrating concentration addition. Growth of E. canadensis and M. spicatum was not reduced indicating that herbicide exposure did not impair plant development. Although PE measurements turned out to be a sensitive method to monitor PSII herbicides, plant growth remains the more relevant ecological endpoint in risk assessment. - Short-term effects on photosynthesis did not result in growth reduction of submerse macrophytes exposed to PSII inhibitors.

  14. Numerical simulation and performance prediction in multi-stage submersible centrifugal pump

    International Nuclear Information System (INIS)

    Wang, W J; Li, G D; Wang, Y; Cui, Y R; Yin, G; Peng, S

    2013-01-01

    In order to study the inner flow field of multi-stage submersible centrifugal pump, the model named QD3-60/4-1.1 was selected. Steady turbulence characteristics of impellers, diffusers and return channel were calculated by Fluent software, the SIMPLEC algorithm and RNG κ-ε turbulence model with sliding mesh technology. Then, the distributions of pressure, velocity and Turbulence kinetic energy was obtained and the distributions of velocity field of a channel were analysed. The results show that the static pressure in impeller is increasing with the increasing of radius. The circumferential component of relative velocity is in the opposite direction of impeller rotating. At the same radius, the component value of pressure surface is larger than suction surface. With the increasing of flow rate, absolute velocity and relative velocity flow angle are becoming small, in opposite of the relative velocity and absolute velocity flow angle. The high turbulent zone of impeller is located in the gap of impellers and diffusers. Flow similarity and structure similarity of the multi-stage submersible pump are confirmed

  15. Study Of Calculation Of Degaussing System For Reducing Magnetic Field From Submersible Vehicle

    Directory of Open Access Journals (Sweden)

    Sardono Sarwito

    2017-03-01

    Full Text Available The rapid development of maritime technology in the world to make Indonesia are also increasingly taking the development of maritime technology, such as in a Submersible Vehicle one is degaussing system, this technology should be owned by the vessel so that the vessel can avoid dangerous explosive equipment contained in the sea. Degaussing system is a system that is in use on the metal parts or electronic devices that are at risk of a magnetic field. This system is used to prevent the vessel from dangerous equipment in the sea which can trigger an explosion and the damage that utilize magnetic fields as a metal-detection sensor when the boat was doing dives. To the authors will plan the design degaussing system, and calculating the system in order to reduce the magnetic properties of the Submersible Vehicle which were obtained by the use of Coil Degaussing along 214,5 meters, a diameter of 0,2, with 500.000 coil that will generate a current of 0,0157 Ampere's 0.0787 Tesla generates a magnetic field.

  16. Oxidative stress mediated toxicity of TiO2 nanoparticles after a concentration and time dependent exposure of the aquatic macrophyte Hydrilla verticillata.

    Science.gov (United States)

    Spengler, Annette; Wanninger, Lena; Pflugmacher, Stephan

    2017-09-01

    The present study focused on oxidative stress effects in the aquatic macrophyte Hydrilla verticillata after exposure to titanium dioxide nanoparticles (TiO 2 -NPs). Experiments were conducted with different TiO 2 -NPs and concentrations (0.1 mg/L and 10 mg/L) in a time-dependent manner (0 h, 24 h, 48 h, 96 h, 168 h). To assess various levels of the oxidative stress response in H. verticillata, the level of hydrogen peroxide (H 2 O 2 ), the ratio of reduced to oxidized glutathione (GSH/GSSG), and activities of the antioxidative enzymes catalase (CAT) and glutathione reductase (GR) were evaluated. Study results imply oxidative stress effects after TiO 2 -NP exposure as adaptations in plant metabolism became apparent to counteract increased ROS formation. All TiO 2 -NPs caused elevated activities of the enzymes CAT and GR. Moreover, decreased ratios of GSH/GSSG indicated an activation of GSH-dependent pathways counteracting ROS formation. Plants exposed to a bulk-sized control revealed a size-dependent influence on the antioxidative stress response. As H 2 O 2 level increases were solely detected after exposure to 10 mg/L TiO 2 -NPs and nano-exposed plants showed normalization in its antioxidative stress response after 168h of exposure, it can be suggested that macrophytes are able to cope with currently predicted low-level exposures to TiO 2 -NPs. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Deepwater marine litter densities and compsoition from submersible video-gransects around the ABC-islands, Dutch Caribbean

    NARCIS (Netherlands)

    Debrot, A.O.; Vinke, E.; Wende, van der G.; Hylkema, A.; Reed, J.K.

    2014-01-01

    Baseline data on anthropogenic seafloor debris contamination in the year 2000 is provided for 24 submersible video transects at depths of 80–900 m, off the Dutch ABC-islands (Aruba, Bonaire, Curaçao), in the southeastern Caribbean Sea. In total, 202 objects were documented from a combined 21,184 m

  18. Towards improved management of coastal submersion crises – CRISMA-WAVE solution as an example of CRISMA Framework application

    Directory of Open Access Journals (Sweden)

    Erlich Marc

    2016-01-01

    Full Text Available Coping with various types of natural or man-made hazards the FP7 SECURITY CRISMA project (http://www.crismaproject.eu has designed and developed an experimental software framework allowing building crisis management simulation application. One of the five pilot applications of CRISMA dealing with preparedness to the coastal submersions was developed and implemented using return of experience of the reference Xynthia storm surge event in the Charente Maritime County in France. The paper addresses the generic CRISMA Framework applicability to simulate mitigation effects of a coastal submersion through CRISMA-Wave implementation of a full modelling cycle. The CRISMA-Wave paradigm reflects user needs for simulation of “what-if” scenarios for short and long-term actions and the paper describes in particular its different components : *Simulation of submersion effects at a range of temporal and spatial scales, *Preparedness Planning, *Assessment of impacts depending on scenarios based on options for managing the inundation risks, *Cascading effects and *Evaluation of damages with comparison of submersion defence scenarios based on cost-benefit and multi criteria analysis.

  19. Roothairless5, which functions in maize (Zea mays L.) root hair initiation and elongation encodes a monocot-specific NADPH oxidase.

    Science.gov (United States)

    Nestler, Josefine; Liu, Sanzhen; Wen, Tsui-Jung; Paschold, Anja; Marcon, Caroline; Tang, Ho Man; Li, Delin; Li, Li; Meeley, Robert B; Sakai, Hajime; Bruce, Wesley; Schnable, Patrick S; Hochholdinger, Frank

    2014-09-01

    Root hairs are instrumental for nutrient uptake in monocot cereals. The maize (Zea mays L.) roothairless5 (rth5) mutant displays defects in root hair initiation and elongation manifested by a reduced density and length of root hairs. Map-based cloning revealed that the rth5 gene encodes a monocot-specific NADPH oxidase. RNA-Seq, in situ hybridization and qRT-PCR experiments demonstrated that the rth5 gene displays preferential expression in root hairs but also accumulates to low levels in other tissues. Immunolocalization detected RTH5 proteins in the epidermis of the elongation and differentiation zone of primary roots. Because superoxide and hydrogen peroxide levels are reduced in the tips of growing rth5 mutant root hairs as compared with wild-type, and Reactive oxygen species (ROS) is known to be involved in tip growth, we hypothesize that the RTH5 protein is responsible for establishing the high levels of ROS in the tips of growing root hairs required for elongation. Consistent with this hypothesis, a comparative RNA-Seq analysis of 6-day-old rth5 versus wild-type primary roots revealed significant over-representation of only two gene ontology (GO) classes related to the biological functions (i.e. oxidation/reduction and carbohydrate metabolism) among 893 differentially expressed genes (FDR <5%). Within these two classes the subgroups 'response to oxidative stress' and 'cellulose biosynthesis' were most prominently represented. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  20. Characterization of a 65 kDa NIF in the nuclear matrix of the monocot Allium cepa that interacts with nuclear spectrin-like proteins.

    Science.gov (United States)

    Pérez-Munive, Clara; Blumenthal, Sonal S D; de la Espina, Susana Moreno Díaz

    2012-01-01

    Plant cells have a well organized nucleus and nuclear matrix, but lack orthologues of the main structural components of the metazoan nuclear matrix. Although data is limited, most plant nuclear structural proteins are coiled-coil proteins, such as the NIFs (nuclear intermediate filaments) in Pisum sativum that cross-react with anti-intermediate filament and anti-lamin antibodies, form filaments 6-12 nm in diameter in vitro, and may play the role of lamins. We have investigated the conservation and features of NIFs in a monocot species, Allium cepa, and compared them with onion lamin-like proteins. Polyclonal antisera against the pea 65 kDa NIF were used in 1D and 2D Western blots, ICM (imunofluorescence confocal microscopy) and IEM (immunoelectron microscopy). Their presence in the nuclear matrix was analysed by differential extraction of nuclei, and their association with structural spectrin-like proteins by co-immunoprecipitation and co-localization in ICM. NIF is a conserved structural component of the nucleus and its matrix in monocots with Mr and pI values similar to those of pea 65 kDa NIF, which localized to the nuclear envelope, perichromatin domains and foci, and to the nuclear matrix, interacting directly with structural nuclear spectrin-like proteins. Its similarities with some of the proteins described as onion lamin-like proteins suggest that they are highly related or perhaps the same proteins.

  1. Optimum water depth ranges of dominant submersed macrophytes in a natural freshwater lake.

    Science.gov (United States)

    Ye, Bibi; Chu, Zhaosheng; Wu, Aiping; Hou, Zeying; Wang, Shengrui

    2018-01-01

    Macrophytes show a zonal distribution along the lake littoral zone because of their specific preferred water depths while the optimum growth water depths of dominant submersed macrophytes in natural lakes are not well known. We studied the seasonal biomass and frequency patterns of dominant and companion submersed macrophytes along the water depth gradient in Lake Erhai in 2013. The results showed that the species richness and community biomass showed hump-back shaped patterns along the water depth gradient both in polydominant and monodominant communities. Biomass percentage of Potamogenton maackianus showed a hump-back pattern while biomass percentages of Ceratophyllum demersum and Vallisneria natans appeared U-shaped patterns across the water depth gradient in polydominant communities whereas biomass percentage of V. natans increased with the water depth in monodominant communities. Dominant species demonstrated a broader distribution range of water depth than companion species. Frequency and biomass of companion species declined drastically with the water depth whereas those of dominant species showed non-linear patterns across the water depth gradient. Namely, along the water depth gradient, biomass of P. maackianus and V. natans showed hump-back patterns and biomasses of C. demersum displayed a U-shaped pattern in the polydominant communities but biomass of V. natans demonstrated a hump-back pattern in the monodominant communities; frequency of P. maackianus showed a hump-back pattern and C. demersum and V. natans maintained high frequencies in the two types of communities. We can speculate that in Lake Erhai the optimum growth water depths of P. maackianus and C. demersum in the polydominant communities are 2.5-4.5 m and 1-2 m or 5-6 m, respectively and that of V. natans is 3-5 m in the polydominant communities and 2.5-5 m in the monodominant communities. This is the first report that the optimum water depth ranges in the horizontal direction of three

  2. Epidemiology of non-submersion injuries in aquatic sporting and recreational activities.

    Science.gov (United States)

    Chalmers, David; Morrison, Luke

    2003-01-01

    Although the issues of drowning and near-drowning in aquatic sporting and recreational activities receive considerable attention in the epidemiological literature, there is not a recognised literature on non-submersion injuries occurring in these activities. This review draws together the epidemiological literature on non-submersion injuries and describes the incidence, nature and causes of these injuries, common risk factors, and strategies for prevention. Activities covered by the review include swimming, diving, boating, surf sports, fishing, water polo and water sliding. For most activities there is a dearth of good quality descriptive studies, with most involving cases-series designs and few providing estimates of incidence. Inconsistencies in inclusion criteria and the reporting of incidence rates makes comparisons within and between activities difficult. Incidence rates were identified for most activities and in general the incidence of injury was low, especially for more serious injury. However, some activities were associated with severely disabling injury, such as spinal cord injury (diving) and amputation (from propeller strikes in water skiing and swimming). Only three studies reporting the significance of postulated risk factors were identified. Lack of knowledge about the water being entered and alcohol consumption are significant risk factors in recreational diving; increased blood alcohol concentrations were reported to increase the risk of death in boating; and obesity and tandem riding were reported to increase the risk of injury on public water slides. Few evaluations of preventive measures were identified. Two studies reported reductions in the incidence of water slide injuries following the introduction of design changes and supervision, but neither had a non-intervention comparison group. Improvements in swimming and diving skills were reported in three studies, but these were not designed to measure changes in the risk of injury.This review

  3. Submersed aquatic vegetation in Chesapeake Bay: Sentinel species in a changing world

    Science.gov (United States)

    Orth, Robert J.; Dennison, William C.; Lefcheck, Jonathon S.; Gurbisz, Cassie; Hannam, Michael; Keisman, Jennifer; Landry, J. Brooke; Moore, Kenneth A.; Murphy, Rebecca R.; Patrick, Christopher J.; Testa, Jeremy; Weller, Donald E.; Wilcox, David J.

    2017-01-01

    Chesapeake Bay has undergone profound changes since European settlement. Increases in human and livestock populations, associated changes in land use, increases in nutrient loadings, shoreline armoring, and depletion of fish stocks have altered the important habitats within the Bay. Submersed aquatic vegetation (SAV) is a critical foundational habitat and provides numerous benefits and services to society. In Chesapeake Bay, SAV species are also indicators of environmental change because of their sensitivity to water quality and shoreline development. As such, SAV has been deeply integrated into regional regulations and annual assessments of management outcomes, restoration efforts, the scientific literature, and popular media coverage. Even so, SAV in Chesapeake Bay faces many historical and emerging challenges. The future of Chesapeake Bay is indicated by and contingent on the success of SAV. Its persistence will require continued action, coupled with new practices, to promote a healthy and sustainable ecosystem.

  4. The Need Of A Phenological Spectral Library Of Submersed Macrophytes For Lake Monitoring

    Science.gov (United States)

    Wolf, Patrick; Robler, Sebastian; Schneider, Thomas; Melzer, Arnulf

    2013-12-01

    Submersed macrophytes are bio-indicators for water quality. For plant monitoring by remote sensing, in-situ reflectance measurements are necessary. Hence, systematic measurements were carried out at Lake Starnberg and Lake Tegernsee (Germany) in the year 2011. Besides two wide-spread species (Chara spp. and Potamogeton perfoliatus), the invasive species Elodea nuttallii and Najas marina were investigated. Remote sensing reflectances were calculated from downwelling irradiance and upwelling radiance. Those were collected with RAMSES spectroradiometers (320nm-950nm, 3.3nm step). As data collection took place several times, changes in the spectral responses within the growing season were detected and could be linked to population density, growing height, biomass and pigmentation. Additionally, a stable sampling method and a processing chain for the in-situ reflectance measurements were developed. Part of the processing was a water column correction, including WASI (water colour simulator). Principal component analysis showed separability of sediment from vegetation and species differentiation.

  5. Counteracting ammonia inhibition during anaerobic digestion by recovery using submersible microbial desalination cell

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2015-01-01

    Ammonia inhibition is one of the most frequent and serious problems in biogas plants. In this study, a novel hybrid system consisting of a submersible microbial desalination cell (SMDC) and a continuous stirred tank reactor (CSTR) was developed for counteracting ammonia inhibition during anaerobic...... digestion (AD) with simultaneous in situ ammonia recovery and electricity production. The SMDC was powered by acetate in a buffer solution, while synthetic ammonia-rich wastewater was used as the feeding of the CSTR. Under continuous operation, ammonia recovery rate of 86 g-N/m2 /day and current density...... of 4.33 A/m2 were achieved at steady-state condition. As a result, 112% extra biogas was produced due to ammonia recovery by the SMDC. High-throughput sequencing showed that ammonia recovery had an impact on the microbial community structures in the SMDC and CSTR. Considering the additional economic...

  6. Sensitivity of submersed freshwater macrophytes and endpoints in laboratory toxicity tests

    International Nuclear Information System (INIS)

    Arts, Gertie H.P.; Belgers, J. Dick M.; Hoekzema, Conny H.; Thissen, Jac T.N.M.

    2008-01-01

    The toxicological sensitivity and variability of a range of macrophyte endpoints were statistically tested with data from chronic, non-axenic, macrophyte toxicity tests. Five submersed freshwater macrophytes, four pesticides/biocides and 13 endpoints were included in the statistical analyses. Root endpoints, reflecting root growth, were most sensitive in the toxicity tests, while endpoints relating to biomass, growth and shoot length were less sensitive. The endpoints with the lowest coefficients of variation were not necessarily the endpoints, which were toxicologically most sensitive. Differences in sensitivity were in the range of 10-1000 for different macrophyte-specific endpoints. No macrophyte species was consistently the most sensitive. Criteria to select endpoints in macrophyte toxicity tests should include toxicological sensitivity, variance and ecological relevance. Hence, macrophyte toxicity tests should comprise an array of endpoints, including very sensitive endpoints like those relating to root growth. - A range of endpoints is more representative of macrophyte fitness than biomass and growth only

  7. Algorithm to determine electrical submersible pump performance considering temperature changes for viscous crude oils

    Energy Technology Data Exchange (ETDEWEB)

    Valderrama, A. [Petroleos de Venezuela, S.A., Distrito Socialista Tecnologico (Venezuela); Valencia, F. [Petroleos de Venezuela, S.A., Instituto de Tecnologia Venezolana para el Petroleo (Venezuela)

    2011-07-01

    In the heavy oil industry, electrical submersible pumps (ESPs) are used to transfer energy to fluids through stages made up of one impeller and one diffuser. Since liquid temperature increases through the different stages, viscosity might change between the inlet and outlet of the pump, thus affecting performance. The aim of this research was to create an algorithm to determine ESPs' performance curves considering temperature changes through the stages. A computational algorithm was developed and then compared with data collected in a laboratory with a CG2900 ESP. Results confirmed that when the fluid's viscosity is affected by the temperature changes, the stages of multistage pump systems do not have the same performance. Thus the developed algorithm could help production engineers to take viscosity changes into account and optimize the ESP design. This study developed an algorithm to take into account the fluid viscosity changes through pump stages.

  8. Catamaran or semi-submersible for floating platform - selection of a better design

    Science.gov (United States)

    Qasim, Idrees; Gao, Liangtian; Peng, Duojin; Liu, Bo

    2018-02-01

    With nonstop advancement in marine engineering, more and more new structures are being designed and explored for tidal current energy. There are three different kinds of support structures for tidal current power station mostly in use, which are sea-bed mounted/gravity based system, pile mounted system and floating moored platform. Comparing all of them, the floating mooring system is most suitable for deep water systems and the application of this arrangement is widely usable. In this paper, a semi-submersible and a catamaran as floating platforms for tidal current power stations are studied are compared on the basis of its economics, efficiency of turbine and stability of the station. Based on basic ship theory and using software MAXSURF, the stability of Catamaran tidal current power station is also calculated. It is found that the catamaran design is optimal choice.

  9. Phytotoxicity of atrazine, isoproturon, and diuron to submersed macrophytes in outdoor mesocosms.

    Science.gov (United States)

    Knauert, Stefanie; Singer, Heinz; Hollender, Juliane; Knauer, Katja

    2010-01-01

    The submersed macrophytes Elodea canadensis, Myriophyllum spicatum and Potamogeton lucens were constantly exposed over a five-week period to environmentally relevant concentrations of atrazine, isoproturon, diuron, and their mixture in outdoor mesocosms. Effects were evaluated investigating photosynthetic efficiency (PE) of the three macrophytes and growth of M. spicatum and E. canadensis. Adverse effects on PE were observed on days 2 and 5 after application. M. spicatum was found to be the more sensitive macrophyte. E. canadensis and P. lucens were less sensitive to atrazine, diuron and the mixture and insensitive to isoproturon. PE of M. spicatum was similarly affected by the single herbicides and the mixture demonstrating concentration addition. Growth of E. canadensis and M. spicatum was not reduced indicating that herbicide exposure did not impair plant development. Although PE measurements turned out to be a sensitive method to monitor PSII herbicides, plant growth remains the more relevant ecological endpoint in risk assessment.

  10. PHYSICAL PROPERTIES OF KAOLIN/SAND SLURRY USED DURING SUBMERSIBLE MIXER PUMP TESTS AT TNX

    International Nuclear Information System (INIS)

    HANSEN, ERICH

    2005-01-01

    The purpose of this task is to characterize the physical properties of the kaolin/sand slurries used during the testing of a new submersible mixer pump (SMP) which had undergone performance testing at the TNX Waste Tank mockup facility from July 2004 through May 2005. During this time period, four identical SMPs were subjected to various water tests and four different tests using different batches of kaolin/sand slurries. The physical properties of the kaolin/sand slurries were measured for three of the four tests. In these tests, three different sample locations were used to pull samples, the SMP cooling water exit (CWE), the SMP fluid flow field (FFF), and SMP effective cleaning radius (ECR). The physical properties measured, though not for each sample, included rheology, weight percent total solids (wt% TS), density, kaolin/sand slurry particle size distribution (PSD), weight percent and particles size distribution of material greater than 45 microns

  11. Effects of high nitrogen concentrations on the growth of submersed macrophytes at moderate phosphorus concentrations.

    Science.gov (United States)

    Yu, Qing; Wang, Hong-Zhu; Li, Yan; Shao, Jian-Chun; Liang, Xiao-Min; Jeppesen, Erik; Wang, Hai-Jun

    2015-10-15

    Eutrophication of lakes leading to loss of submersed macrophytes and higher turbidity is a worldwide phenomenon, attributed to excessive loading of phosphorus (P). However, recently, the role of nitrogen (N) for macrophyte recession has received increasing attention. Due to the close relationship between N and P loading, disentanglement of the specific effects of these two nutrients is often difficult, and some controversy still exists as to the effects of N. We studied the effects of N on submersed macrophytes represented by Vallisneria natans (Lour.) Hara in pots positioned at three depths (0.4 m, 0.8 m, and 1.2 m to form a gradient of underwater light conditions) in 10 large ponds having moderate concentrations of P (TP 0.03 ± 0.04 mg L(-1)) and five targeted concentrations of total nitrogen (TN) (0.5, 2, 10, 20, and 100 mg L(-1)), there were two ponds for each treatment. To study the potential shading effects of other primary producers, we also measured the biomass of phytoplankton (ChlaPhyt) and periphyton (ChlaPeri) expressed as chlorophyll a. We found that leaf length, leaf mass, and root length of macrophytes declined with increasing concentrations of TN and ammonium, while shoot number and root mass did not. All the measured growth indices of macrophytes declined significantly with ChlaPhyt, while none were significantly related to ChlaPeri. Neither ChlaPhyt nor ChlaPeri were, however, significantly negatively related to the various N concentrations. Our results indicate that shading by phytoplankton unrelated to the variation in N loading and perhaps toxic stress exerted by high nitrogen were responsible for the decline in macrophyte growth. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Conductive heat flow at the TAG Active Hydrothermal Mound: Results from 1993-1995 submersible surveys

    Science.gov (United States)

    Becker, K.; Von Herzen, R.; Kirklin, J.; Evans, R.; Kadko, D.; Kinoshita, M.; Matsubayashi, O.; Mills, R.; Schultz, A.; Rona, P.

    We report 70 measurements of conductive heat flow at the 50-m-high, 200-m-diameter TAG active hydrothermal mound, made during submersible surveys with Alvin in 1993 and 1995 and Shinkai 6500 in 1994. The stations were all measured with 5-thermistor, 0.6- or 1-m-long Alvin heat flow probes, which are capable of determining both gradient and thermal conductivity, and were transponder-navigated to an estimated accuracy of ±5-10 m relative to the 10-m-diameter central complex of black smokers. Within 20 m of this complex, conductive heat flow values are extremely variable (0.1- > 100 W/m²), which can only be due to local spatial and possible temporal variability in the immediate vicinity of the vigorous discharge sites. A similar local variability is suggested in the “Kremlin” area of white smokers to the southeast of the black smoker complex. On the south and southeast side of the mound, there is very high heat flow (3.7- > 25 W/m²) on the sedimented terraces that slope down from the Kremlin area. Heat flow is also high (0.3-3 W/m²) in the pelagic carbonate sediments on the surrounding seafloor within a few tens of meters of the southwest, northwest, and northeast sides of the mound. On the west side of the sulfide rubble plateau that surrounds the central black smoker peak, there is a coherent belt of very low heat flow (smokers, suggestive of local, shallow recharge of bottom water. The three submersible surveys spanned nearly two years, but showed no indication of any temporal variability in conductive heat flow over this time scale, whether natural or induced by ODP drilling in 1994.

  13. Cocoa Beach, Oculina Banks Clelia Dive 617 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of from fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance...

  14. Sebastian Pinnacles, Oculina Banks Clelia Dive 618 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  15. Sebastian Pinnacles, Oculina Banks Clelia Dive 614 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  16. Sebastian Pinnacles, Oculina Banks Clelia Dive 615 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  17. Sebastian Pinnacles, Oculina Banks Clelia Dive 619 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  18. Jeff's Reef, Oculina Banks Clelia Dive 606 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These are data from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  19. Chapman's Reef, Oculina Banks Clelia Dive 620 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  20. stil113_0401p -- Still frame locations of sediment extracted from video imagery collected by Delta submersible in September 2001.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Delta submersible vehicle, outfitted with video equipment (and other devices), was deployed from the R/V Auriga during September 2001 to monitor seafloor...

  1. Jeff's Reef Oculina Banks Clelia Dive 607 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These are data from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  2. Submersible Data (Dive Waypoints) for Islands in the Stream 2002 - Exploration of Outer Shelf and Slope Habitats off the Coast of North Carolina - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link II at waypoints along its track during one dive of the 2002 "Islands in the Stream - Outer Shelf...

  3. Phytoplankton cell counts from a moored submersible flow cytometer at Martha's Vineyard (Massachusetts) Coastal Observatory, May 10 - December 15, 2003 (NODC Accession 0002299)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Phytoplankton cell counts data were collected using a moored submersible flow cytometer from a Coastal Observatory at the Martha's Vineyard in Masschutsetts from 10...

  4. Phytoplankton cell counts from a moored submersible flow cytometer at Martha's Vineyard (Massachusetts) Coastal Observatory, May - December 2006 (NODC Accession 0036656)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Phytoplankton cell counts were collected from using a moored submersible flow cytometer from the Martha's Vineyard Coastal Observatory in the Northwest Atlantic...

  5. Phytoplankton cell counts from a moored submersible flow cytometer at Martha's Vineyard Coastal Observatory, Massachusetts, May - September 2004 (NODC Accession 0002722)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Phytoplankton cell counts were collected from using a moored submersible flow cytometer from the Martha's Vineyard Coastal Observatory in the Northwest Atlantic...

  6. Lack of S-RNase-Based Gametophytic Self-Incompatibility in Orchids Suggests That This System Evolved after the Monocot-Eudicot Split

    Directory of Open Access Journals (Sweden)

    Shan-Ce Niu

    2017-06-01

    Full Text Available Self-incompatibility (SI is found in approximately 40% of flowering plant species and at least 100 families. Although orchids belong to the largest angiosperm family, only 10% of orchid species present SI and have gametophytic SI (GSI. Furthermore, a majority (72% of Dendrobium species, which constitute one of the largest Orchidaceae genera, show SI and have GSI. However, nothing is known about the molecular mechanism of GSI. The S-determinants of GSI have been well characterized at the molecular level in Solanaceae, Rosaceae, and Plantaginaceae, which use an S-ribonuclease (S-RNase-based system. Here, we investigate the hypothesis that Orchidaceae uses a similar S-RNase to those described in Rosaceae, Solanaceae, and Plantaginaceae SI species. In this study, two SI species (Dendrobium longicornu and D. chrysanthum were identified using fluorescence microscopy. Then, the S-RNase- and SLF-interacting SKP1-like1 (SSK1-like genes present in their transcriptomes and the genomes of Phalaenopsis equestris, D. catenatum, Vanilla shenzhenica, and Apostasia shenzhenica were investigated. Sequence, phylogenetic, and tissue-specific expression analyses revealed that none of the genes identified was an S-determinant, suggesting that Orchidaceae might have a novel SI mechanism. The results also suggested that RNase-based GSI might have evolved after the split of monocotyledons (monocots and dicotyledons (dicots but before the split of Asteridae and Rosidae. This is also the first study to investigate S-RNase-based GSI in monocots. However, studies on gene identification, differential expression, and segregation analyses in controlled crosses are needed to further evaluate the genes with high expression levels in GSI tissues.

  7. Numerical Investigation of a Tuned Heave Plate Energy-Harvesting System of a Semi-Submersible Platform

    Directory of Open Access Journals (Sweden)

    Kun Liu

    2016-01-01

    Full Text Available A novel tuned heave plate energy-harvesting system (THPEH is presented for the motion suppressing and energy harvesting of a semi-submersible platform. This THPEH system is designed based on the principle of a tuned mass damper (TMD and is composed of spring supports, a power take-off system (PTO and four movable heave plates. The permanent magnet linear generators (PMLG are used as the PTO system in this design. A semi-submersible platform operating in the South China Sea is selected as the research subject for investigating the effects of the THPEH system on motion reduction and harvesting energy through numerical simulations. The numerical model of the platform and the THPEH system, which was established based on hydrodynamic analysis, is modified and validated by the results of the flume test of a 1:70 scale model. The effects of the parameters, including the size, the frequency ratio and the damping ratio of the THPEH system, are systematically investigated. The results show that this THPEH system, with proper parameters, could significantly reduce the motions of the semi-submersible platform and generate considerable power under different wave conditions.

  8. Linking carbon and nitrogen metabolism to depth distribution of submersed macrophytes using high ammonium dosing tests and a lake survey.

    Science.gov (United States)

    Yuan, Guixiang; Cao, Te; Fu, Hui; Ni, Leyi; Zhang, Xiaolin; Li, Wei; Song, Xin; Xie, Ping; Jeppesen, Erik

    2013-12-01

    Strategies of carbon (C) and nitrogen (N) utilisation are among the factors determining plant distribution. It has been argued that submersed macrophytes adapted to lower light environments are more efficient in maintaining C metabolic homeostasis due to their conservative C strategy and ability to balance C shortage. We studied how depth distributions of 12 submersed macrophytes in Lake Erhai, China, were linked to their C-N metabolic strategies when facing acute [Formula: see text] dosing.[Formula: see text] dosing changed C-N metabolism significantly by decreasing the soluble carbohydrate (SC) content and increasing the [Formula: see text]-N and free amino acid (FAA) content of plant tissues.The proportional changes in SC contents in the leaves and FAA contents in the stems induced by [Formula: see text] dosing were closely correlated (positive for SC and negative for FAA) with the colonising water depths of the plants in Lake Erhai, the plants adapted to lower light regimes being more efficient in maintaining SC and FAA homeostasis.These results indicate that conservative carbohydrate metabolism of submersed macrophytes allowed the plants to colonise greater water depths in eutrophic lakes, where low light availability in the water column diminishes carbohydrate production by the plants.

  9. Studi Pengaruh Gerak Semi-submersible Drilling Rig dengan Variasi Pre-tension Mooring Line terhadap Keamanan Drilling Riser

    Directory of Open Access Journals (Sweden)

    Arda Arda

    2012-09-01

    Full Text Available Analisis terhadap sistem tambat pada anjungan pengeboran semi-submersible drilling rig perlu dilakukan sebelum dilakukannya operasi di lapangan untuk mengetahui perencanaan sistem tambat yang tepat dan aman. Dalam penelitian ini dilakukan analisa perilaku gerak semi-submersible dengan variasi pre-tension mooring line untuk mengetahui berapa besar pre-tension minimal yang harus digunakan agar operasi pengeboran di lingkungan laut Natuna dapat berjalan dengan aman. Variasi pre-tension yang digunakan adalah sebesar 400kN-2000kN dengan penambahan sebesar 400kN. Karakteristik gerakan semi-submersible diprediksi dengan menghitung RAO free floating dengan pemodelan numerik dalam domain frekuensi. Kemudian dilakukan analisa simulasi sistem lengkap (platform, mooring dan drilling riser dengan pemodelan numerik dalam domain waktu. Hasil yang didapat yakni nilai maksimum tegangan mooring line memenuhi batas kriteria API-RP2SK untuk semua variasi pre-tension dengan safety factor terkecil 2.44. Sudut flex joint drilling riser yang terjadi melewati batas kriteria API-RP16Q pada pre-tension 400kN-800kN yang mencapai 6.20 untuk sudut maksimum dan 4.80 untuk sudut rata-rata. Tegangan von Mises yang terjadi pada drilling riser melebihi kriteria API-RP16Q pada pre-tension 400kN-1200kN karena nilainya mencapai 369 MPa (0.82 yield stress.

  10. Counteracting ammonia inhibition during anaerobic digestion by recovery using submersible microbial desalination cell.

    Science.gov (United States)

    Zhang, Yifeng; Angelidaki, Irini

    2015-07-01

    Ammonia inhibition is one of the most frequent and serious problems in biogas plants. In this study, a novel hybrid system consisting of a submersible microbial desalination cell (SMDC) and a continuous stirred tank reactor (CSTR) was developed for counteracting ammonia inhibition during anaerobic digestion (AD) with simultaneous in situ ammonia recovery and electricity production. The SMDC was powered by acetate in a buffer solution, while synthetic ammonia-rich wastewater was used as the feeding of the CSTR. Under continuous operation, ammonia recovery rate of 86 g-N/m(2) /day and current density of 4.33 A/m(2) were achieved at steady-state condition. As a result, 112% extra biogas was produced due to ammonia recovery by the SMDC. High-throughput sequencing showed that ammonia recovery had an impact on the microbial community structures in the SMDC and CSTR. Considering the additional economic benefits of biogas enhancement and possible wastewater treatment, the SMDC may represent a cost-effective and environmentally friendly method for waste resources recovery and biomethanation of ammonia-rich residues. © 2015 Wiley Periodicals, Inc.

  11. Dynamic Modeling and Simulation of Deep Geothermal Electric Submersible Pumping Systems

    Directory of Open Access Journals (Sweden)

    Julian Kullick

    2017-10-01

    Full Text Available Deep geothermal energy systems employ electric submersible pumps (ESPs in order to lift geothermal fluid from the production well to the surface. However, rough downhole conditions and high flow rates impose heavy strain on the components, leading to frequent failures of the pump system. As downhole sensor data is limited and often unrealible, a detailed and dynamical model system will serve as basis for deeper understanding and analysis of the overall system behavior. Furthermore, it allows to design model-based condition monitoring and fault detection systems, and to improve controls leading to a more robust and efficient operation. In this paper, a detailed state-space model of the complete ESP system is derived, covering the electrical, mechanical and hydraulic subsystems. Based on the derived model, the start-up phase of an exemplary yet realistic ESP system in the Megawatt range—located at a setting depth of 950 m and producing geothermal fluid of 140 ∘ C temperature at a rate of 0.145 m 3 s − 1 —is simulated in MATLAB/Simulink. The simulation results show that the system reaches a stable operating point with realistic values. Furthermore, the effect of self-excitation between the filter capacitor and the motor inductor can clearly be observed. A full set of parameters is provided, allowing for direct model implementation and reproduction of the presented results.

  12. Classification of submersed aquatic vegetation of the Venice lagoon using MIVIS airborne data

    Directory of Open Access Journals (Sweden)

    S. Pignatti

    2006-06-01

    Full Text Available In July 2001 an aerial survey with MIVIS (Multispectral Infrared and Visible Spectrometer hyperspectral sensor and an in situ survey campaign were performed on Venice lagoon to map benthic macro-algae and sea phanerogams distribution. On MIVIS VIS spectral range images, training areas for benthic macro-algae and sea phanerogams have been selected by using sea truth data collected by CNR-ISMAR from in situ campaign and periodic area surveys used in the lagoon by the local authorities. The derived spectral signature has been used to classify the area in order to produce the maps of the pure and mixture submersed vegetation population. The algorithm applied to the data is based on the Subpixel Spectral Analytical Process (SSAP method. The method assumes that the spectrum of a single pixel is composed of a fraction of the material of interest while the remainder of the observed spectra contains background materials. In terms of recognition processes the produced maps present a very good agreement with the sea truth data even though the fraction material expressed in the maps does not represent a quantitative estimation of the material of interest.

  13. Carbon dioxide and submersed macrophytes in lakes: linking functional ecology to community composition.

    Science.gov (United States)

    Titus, John E; Pagano, Angela M

    2017-12-01

    Evaluating plant community response to atmospheric CO 2 rise is critical to predicting ecosystem level change. Freshwater lakes offer a model system for examining CO 2 effects as submersed macrophyte species differ greatly in their growth responses to CO 2 enrichment, and free CO 2 concentrations among these habitats show a wide range of natural, spatial variation. We determined free CO 2 concentrations in the water column and sediment porewater in littoral zones with pH macrophyte communities coupled with greenhouse-derived growth responses to CO 2 enrichment of constituent species to test two hypotheses: (1) CCRI, which is higher for communities dominated by species with greater growth responses to CO 2 enrichment, is positively correlated to free [CO 2 ] in the water column, and (2) in natural communities, the percent of sediment CO 2 -using species, which are relatively unresponsive to CO 2 enrichment, is negatively correlated to free [CO 2 ]. A significant positive correlation (P = 0.003) between our physiologically based CCRI and the concentration of free CO 2 in the water column supported our primary hypothesis that sites with higher levels of free CO 2 are dominated by species with greater growth responses to CO 2 enrichment. Our CCRI is also highly significantly correlated (P macrophyte community composition. Further, we demonstrate the utility of a physiologically-based index of community composition, our CCRI, as an ecologically valid measure of community response to CO 2 . © 2017 by the Ecological Society of America.

  14. Development for LMR coolant technology - Development of a submersible-in-pool electromagnetic pump

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sang Hee; Kim, Hee Reyoung; Lee, Sang Don; Seo, Chun Ho [Seoul National University, Seoul (Korea, Republic of); Cho, Su Won [Kyungki University, Suwon (Korea, Republic of)

    1995-08-01

    The conceptual and detailed designs of an annular linear induction electromagnetic pump of small scale submersible-in-pool type are performed for the purpose of domestic development of the pumps used for the high-temperature natrium coolant transportation in liquid metal reactors. The pump drawings for and input power of 1,100 VA, an input frequency of 17 Hz, a maximum flowrate of 60 l/min and a maximum operation temperature of 600 deg C are obtained from the optimum design analyses by solving MHD and equivalent circuit equations. The characteristics of pump materials in the high temperature and neutron irradiation environment are reflected in designing the pump, and theoretical analyses for improving the pump performance and efficiency are tried through calculations of magnetic flux and temperature distributions inside the pump. The present project contributes to the further design of engineering proto-type electromagnetic pump with higher capacity and the development of liquid metal reactor with innovative simplicity. 44 refs., 4 tabs., 33 figs. (author)

  15. Ocean Economy and Fault Diagnosis of Electric Submersible Pump applied in Floating platform

    Directory of Open Access Journals (Sweden)

    Panlong Zhang

    2017-04-01

    Full Text Available Ocean economy plays a crucial role in the strengthening maritime safety industry and in the welfare of human beings. Electric Submersible Pumps (ESP have been widely used in floating platforms on the sea to provide oil for machines. However, the ESP fault may lead to ocean environment pollution, on the other hand, a timely fault diagnosis of ESP can improve the ocean economy. In order to meet the strict regulations of the ocean economy and environmental protection, the fault diagnosis of ESP system has become more and more popular in many countries. The vibration mechanical models of typical faults have been able to successfully diagnose the faults of ESP. And different types of sensors are used to monitor the vibration signal for the signal analysis and fault diagnosis in the ESP system. Meanwhile, physical sensors would increase the fault diagnosis challenge. Nowadays, the method of neural network for the fault diagnosis of ESP has been applied widely, which can diagnose the fault of an electric pump accurately based on the large database. To reduce the number of sensors and to avoid the large database, in this paper, algorithms are designed based on feature extraction to diagnose the fault of the ESP system. Simulation results show that the algorithms can achieve the prospective objectives superbly.

  16. Development of LMR Coolant Technology - Development of a submersible-in-pool electromagnetic pump

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sang Hi; Kim, Hee Reyoung; Lee, Sang Don; Seo, Joon Ho [Seoul National University, Seoul (Korea, Republic of); Cho, Su Won [Kyoungki University, Suwon (Korea, Republic of)

    1997-07-15

    A submersible-in-pool type annular linear induction pumps of 60 l/min and 200 l/min, and 600 deg C has been designed with optimum geometrical and operating values found from MHD and circuit analyses reflecting the high-temperature characteristics of pump materials. Through the characteristics analyses inside the narrow flow channel of electromagnetic pump, the distribution of the time-varying flow field is calculated, and magnetic flux and force density are evaluated by end effects of linear induction electromagnetic pump and the instability analyses are carried out introducing one-dimensional linear perturbation. Testing the pump with the flow rate of 60 l/min in the suitably manufactured loop system shows a flow rate of 58 l/min at an input power of 1,377 VA with 60Hz. The design of a scaled-up pump is further taken into account LMR coolant system requiring increased capacity, and a basic analysis is carried out on the pump of 40,000 l/min for KALIMER. The present project contributes to the further design of engineering prototype electromagnetic pumps with higher capacity and to the development of liquid metal reactor with innovative simplicity. 89 refs., 8 tabs., 45 figs. (author)

  17. FUZZY LOGIC BASED OPTIMIZATION OF CAPACITOR VALUE FOR SINGLE PHASE OPEN WELL SUBMERSIBLE INDUCTION MOTOR

    Directory of Open Access Journals (Sweden)

    R. Subramanian

    2011-01-01

    Full Text Available Purpose – The aim of this paper is to optimize the capacitor value of a single phase open well submersible motor operating under extreme voltage conditions using fuzzy logic optimization technique and compared with no-load volt-ampere method. This is done by keeping the displacement angle (a between main winding and auxiliary winding near 90o, phase angle (f between the supply voltage and line current near 0o. The optimization work is carried out by using Fuzzy Logic Toolbox software built on the MATLAB technical computing environment with Simulink software. Findings – The optimum capacitor value obtained is used with a motor and tested for different supply voltage conditions. The vector diagrams obtained from the experimental test results indicates that the performance is improved from the existing value. Originality/value – This method will be highly useful for the practicing design engineers in selecting the optimum capacitance value for single phase induction motors to achieve the best performance for operating at extreme supply voltage conditions.

  18. Development of miniaturized submersible fluorometers for the detection of aromatic hydrocarbons in marine waters

    Science.gov (United States)

    Tedetti, Marc; Bachet, Caroline; Joffre, Pascal; Ferretto, Nicolas; Guigue, Catherine; Goutx, Madeleine

    2014-05-01

    Polycyclic aromatic hydrocarbons (PAHs) are among the most widespread organic contaminants in aquatic environments. Due to their physico-chemical properties, PAHs are persistent and mobile, can strongly bioaccumulate in food chains and are harmful to living organisms. They are thus recognized by various international organizations as priority contaminants and are included in the list of 45 priority regulated substances by the European Union. Because of their aromatic structure, PAHs are "optically active" and have inherent fluorescence properties in the ultraviolet (UV) spectral domain (200-400 nm). Therefore, UV fluorescence spectroscopy has been successfully used to develop PAH sensors (i.e. UV fluorometers). Currently, five UV submersible fluorometers are commercially available for in situ measurements of PAHs: EnviroFlu-HC (TriOS Optical Sensors, Germany), Hydrocarbon Fluorometer (Sea & Sun Technology, Germany), HydroC ™ / PAH (CONTROS, Germany), UviLux AquaTracka (Chelsea Technology Group, UK) and Cyclops-7 (Turner Designs, US). These UV fluorometers are all dedicated to the measurement of phenanthrene (λEx /λEm: 255/360 nm), one of the most abundant and fluorescent PAHs found in the aquatic environment. In this study, we developed original, miniaturized submersible fluorometers based on deep UV light-emitting diodes (LEDs) for simultaneous measurements of two PAHs of interest: the MiniFluo-UV 1 for the detection of phenanthrene (PHE, at λEx /λEm: 255/360 nm) and naphthalene (NAP, at λEx /λEm: 270/340 nm), and the MiniFluo-UV 2 for the detection of fluorene (FLU, at λEx /λEm: 255/315 nm) and pyrene (PYR, at λEx /λEm: 270/380 nm). The MiniFluo-UV sensors have several features: measurements of two PAHs at the same time, small size (puck format, 80 x 60 mm), very low energy consumption (500 mW at 12V), LED monitoring, analog and numerical communication modes. The two MiniFluo-UV sensors were first tested in the laboratory: 1) on standard solutions of

  19. DORADO/DOLPHIN: A Unique Semi-submersible Autonomous Vehicle for Ocean Field Experiments.

    Science.gov (United States)

    Wallace, D.

    2016-02-01

    The Ocean Science and Technology research group (CERC.OCEAN) at Dalhousie University focuses on new approaches to the design and development of autonomous platforms to study biogeochemical and ecological changes in the world's oceans. Mesoscale "patch" experiments involving tracers are used to test hypotheses (e.g. iron fertilization) and examine near-surface processes and air-sea exchange. Such experiments typically require mapping of rapidly-evolving properties on scales of 10's to 100's of kilometers. These experiments typically employ a research vessel to monitor patch movement and to support process studies: however allocation of expensive vessel time between these uses can be problematic. We present a class of autonomous vehicle with unique potential for mesoscale mapping and experimental science at sea. The Dorado/Dolphin semi-submersibles, manufactured by International Submarine Engineering Ltd., travel just below the sea surface. A surface-piercing, "snorkel" mast allows use of a diesel engine allowing speeds of up to 16 knots and sufficient power for support of complex payloads. A tow-body can profile to 200m. The mast allows air sampling with near-zero atmospheric disturbance as well as remote sensing of the sea surface. The characteristics of this type of vehicle will be compared with those of other available platforms. We will report on our adaptation of the vehicle for measurement of gases and purposeful tracers (e.g. SF5CF3) as well as properties such as T, S, pCO2, O2, fluorescence, etc. and present and solicit ideas for the vehicles' further application/use for ocean science.

  20. Lightweight submersed 'Walking' NDE manipulators for PWR and BWR vessel weld inspection

    International Nuclear Information System (INIS)

    Saernmark, Ivan; Lenz, Herbert

    2008-01-01

    Three new manipulators developed by WesDyne TRC in Sweden have under the year 2007 performed three very successful inspections in the PWR reactor Ringhals 3 and the BWR reactors Ringhals 1 and Oskarshamn 1. The manipulator systems can be used to perform inspection of circumferential and vertical welds on the reactor pressure vessel, the core shroud, core shroud support in BWR reactors or vessel and core barrel welds in PWR reactors. Most other flat or curved surfaces can be inspected using the new concept through relatively simple mechanical reconfigurations of system modules. The first inspection was performed on the R3 PWR core barrel in June 2007 with a very good result. This Manipulator is designed for access in very narrow gaps and for the type of core barrels with a shield covering the whole area of the perimeter. The manipulator is attached to the inspection area by means of a new unique suction cup system. The current manipulators consist of a curved horizontal beam, with radius similar to the reactor vessel, and a straight vertical beam, forming a T-shaped structure. By alternating the application of suction cup pairs on the horizontal beam and the vertical beam and by driving the scanning motors, the manipulator performs an incremental translational movement upwards/downwards or from side to side. The principles of this system give a well defined and stable platform for global and local positioning accuracy. A combination of advanced sensor solutions provides accurate position information in the absence of other physical reference objects. The system is controlled by the new WesDyne TRC Motor Control Panel and software, the MCP is specifically designed for remote control of submersed manipulators using techniques for cable reduction

  1. Lightweight submersed 'Walking' NDE manipulators for PWR and BWR vessel weld inspection

    Energy Technology Data Exchange (ETDEWEB)

    Saernmark, Ivan; Lenz, Herbert [WesDyne TRC AB, Stockholm (Sweden)

    2008-04-15

    Three new manipulators developed by WesDyne TRC in Sweden have under the year 2007 performed three very successful inspections in the PWR reactor Ringhals 3 and the BWR reactors Ringhals 1 and Oskarshamn 1. The manipulator systems can be used to perform inspection of circumferential and vertical welds on the reactor pressure vessel, the core shroud, core shroud support in BWR reactors or vessel and core barrel welds in PWR reactors. Most other flat or curved surfaces can be inspected using the new concept through relatively simple mechanical reconfigurations of system modules. The first inspection was performed on the R3 PWR core barrel in June 2007 with a very good result. This Manipulator is designed for access in very narrow gaps and for the type of core barrels with a shield covering the whole area of the perimeter. The manipulator is attached to the inspection area by means of a new unique suction cup system. The current manipulators consist of a curved horizontal beam, with radius similar to the reactor vessel, and a straight vertical beam, forming a T-shaped structure. By alternating the application of suction cup pairs on the horizontal beam and the vertical beam and by driving the scanning motors, the manipulator performs an incremental translational movement upwards/downwards or from side to side. The principles of this system give a well defined and stable platform for global and local positioning accuracy. A combination of advanced sensor solutions provides accurate position information in the absence of other physical reference objects. The system is controlled by the new WesDyne TRC Motor Control Panel and software, the MCP is specifically designed for remote control of submersed manipulators using techniques for cable reduction.

  2. Application of a newly built semi-submersible vessel for transportation of a tension leg platform

    Science.gov (United States)

    Zhang, Dagang; Sun, Weiying; Fan, Zhixia

    2012-09-01

    Transportation of tension leg platform (TLP) structures for a long distance has always been associated with the use of a heavy semi-transport vessel. The requirements of this type of vessel are always special, and their availability is limited. To prepare for the future development of South China Sea deepwater projects, the China Offshore Oil Engineering Corporation has recently built a heavy lift transport vessel-Hai Yang Shi You 278. This semi-submersible vessel has a displacement capacity of 50k DWT, and a breath of 42 meters. Understanding the vessel's applicability and preparing it for use in future deepwater projects are becoming imminent needs. This paper reviews the current critical issues associated with TLP transportation and performs detailed analysis of the designed TLP during load-out and transportation. The newly built COOEC transportation vessel HYSY 278 was applied to dry transport of the TLP structure from the COOEC fabrication yard in Qingdao to an oil field in South China Sea. The entire process included the load-out of the TLP structure from the landsite of the fabrication yard, the offloading and float-on of the platform from the vessel, the dry transport of the TLP over a long distance, and the final offloading of the platform. Both hydrodynamic and structure analysis were performed to evaluate the behavior of the transport vessel and TLP structure. Special attention was paid to critical areas associated with the use of this new vessel, along with any potential limitations. The results demonstrate that HYSY 278 can effectively be used for transporting the structure with proper arrangement and well-prepared operation. The procedure and details were presented on the basis of the study results. Special attention was also given to discussion on future use based on the results from the analysis.

  3. CubeSub - A CubeSat Based Submersible Testbed for Space Technology

    Science.gov (United States)

    Slettebo, Christian

    2016-01-01

    This report is a Master's Thesis in Aerospace Engineering, performed at the NASA Ames Research Center. It describes the development of the CubeSub, a submersible testbed compatible with the CubeSat form factor. The CubeSub will be used to mature technology and operational procedures to be used in space exploration, and possibly also as a tool for exploration of Earthly environments. CubeSats are carried as payloads, either containing technology to be tested or experiments and sensors for scientific use. The CubeSub is designed to be built up by modules, which can be assembled in different configurations to fulfill different needs. Each module is powered individually and intermodular communication is wireless, reducing the need for wiring. The inside of the hull is flooded with ambient water to simplify the interaction between payloads and surrounding environment. The overall shape is similar to that of a conventional AUV, slender and smooth. This is to make for a low drag, reduce the risk of snagging on surrounding objects and make it possible to deploy through an ice sheet via a narrow borehole. Rapid prototyping is utilized to a large extent, with full-scale prototypes being constructed through 3D-printing and with COTS (Commercial Off-The-Shelf) components. Arduino boards are used for control and internal communication. Modules required for basic operation have been designed, manufactured and tested. Each module is described with regards to its function, design and manufacturability. By performing tests in a pool it was found that the basic concept is sound and that future improvements include better controllability, course stability and waterproofing of electrical components. Further development is needed to make the CubeSub usable for its intended purposes. The largest gains are expected to be found by developing the software and improving controllability.

  4. New Submersed Chamber for Calibration of Relative Humidity Instruments at HMI/FSB-LPM

    Science.gov (United States)

    Sestan, D.; Zvizdic, D.; Sariri, K.

    2018-02-01

    This paper gives a detailed description of a new chamber designed for calibration of relative humidity (RH) instruments at Laboratory for Process Measurement (HMI/FSB-LPM). To the present time, the calibrations of RH instruments at the HMI/FSB-LPM were done by comparison method using a climatic chamber of large volume and calibrated dew point hygrometer with an additional thermometer. Since 2010, HMI/FSB-LPM in cooperation with Centre for Metrology and Accreditation in Finland (MIKES) developed the two primary dew point generators which cover the dew point temperature range between - 70 {°}C and 60 {°}C. In order to utilize these facilities for calibrations of the RH instruments, the new chamber was designed, manufactured and installed in the existing system, aiming to extend its range and reduce the related calibration uncertainties. The chamber construction allows its use in a thermostatic bath of larger volume as well as in the climatic chambers. In the scope of this paper, performances of the new chamber were tested while it was submersed in a thermostated bath. The chamber can simultaneously accommodate up to three RH sensors. In order to keep the design of the chamber simple, only cylindrical RH sensors detachable from display units can be calibrated. Possible optimizations are also discussed, and improvements in the design proposed. By using the new chamber, HMI/FSB-LPM reduced the expanded calibration uncertainties (level of confidence 95 %, coverage factor k=2) from 0.6 %rh to 0.25 %rh at 30 %rh (23 {°}C), and from 0.8 %rh to 0.53 %rh at 70 %rh (23 {°}C).

  5. Integrated System Design for a Large Wind Turbine Supported on a Moored Semi-Submersible Platform

    Directory of Open Access Journals (Sweden)

    Jinsong Liu

    2018-01-01

    Full Text Available Over the past few decades, wind energy has emerged as an alternative to conventional power generation that is economical, environmentally friendly and, importantly, renewable. Specifically, offshore wind energy is being considered by a number of countries to harness the stronger and more consistent wind resource compared to that over land. To meet the projected “20% energy from wind by 2030” scenario that was announced in 2006, 54 GW of added wind energy capacity need to come from offshore according to a National Renewable Energy Laboratory (NREL study. In this study, we discuss the development of a semi-submersible floating offshore platform with a catenary mooring system to support a very large 13.2-MW wind turbine with 100-m blades. An iterative design process is applied to baseline models with Froude scaling in order to achieve preliminary static stability. Structural dynamic analyses are performed to investigate the performance of the new model using a finite element method approach for the tower and a boundary integral equation (panel method for the platform. The steady-state response of the system under uniform wind and regular waves is first studied to evaluate the performance of the integrated system. Response amplitude operators (RAOs are computed in the time domain using white-noise wave excitation; this serves to highlight nonlinear, as well as dynamic characteristics of the system. Finally, selected design load cases (DLCs and the stochastic dynamic response of the system are studied to assess the global performance for sea states defined by wind fields with turbulence and long-crested irregular waves.

  6. Modification and co-option of leaf developmental programs for the acquisition of flat structures in monocots: Unifacial leaves in Juncus and cladodes in Asparagus

    Directory of Open Access Journals (Sweden)

    Hokuto eNakayama

    2013-07-01

    Full Text Available It has been suggested that modification and co-option of existing gene regulatory networks (GRNs play an important role in the morphological diversity. In plants, leaf development is one of active research areas, and the basic GRN for leaf development is beginning to be understood. Moreover, leaves show wide variation in their form, and some of this variation is thought to be the result of adaptation. Thus, leaves and leaf-like organs are an emerging and interesting model to reveal how existing GRNs give rise to novel forms and architectures during evolution. In this review, we highlight recent findings in Evo-Devo studies, especially on Juncus unifacial leaves, which are composed of lamina with abaxialized identities, and Asparagus cladodes, which are leaf-like organs at the axils of scale leaves. Based on these studies, we discuss how flat structures have evolved and morphologically diversified in shoot systems of monocot species, focusing on the modification and co-option of GRN for leaf development.

  7. Gravitational and submersible offshore platform, and construction method. Nedsenkbar fralandsplattform av gravitasjonstypen og fremgangsmaate for fremstilling av samme

    Energy Technology Data Exchange (ETDEWEB)

    Berge, T.; Olsen, O.

    1985-06-17

    The invention concerns a submersible offshore platform of the gravitational type designed for great depths. The platform is made of concrete or the like comprising a sea-bed foundation, and a number of at least 3 cantilevered pillars connected to the prop section carrying the load-bearing structure and the platform deck. In addition, the platform consists of a cellular floating section, and the central part of it is lengthened upwards. The central column supports the prop section. There is a considerable space between the floating section and the bed foundation. The various steps of the construction methods are presented. 11 drawings.

  8. Structural analyses of very large semi-submersibles in waves; Choogata hansensuishiki futai no harochu kozo oto kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Iijima, K.; Yoshida, K.; Suzuki, H. [The University of Tokyo, Tokyo (Japan)

    1997-08-01

    An analysis method in which the technique of a vehicle obtained when a three-dimensional singular point distribution method and Kagemoto`s mutual interaction theory are combined was expanded for the fluid area was proposed as the structural analysis of very large semi-submersibles in waves. A partial structure method is used for the structure. In a fluid area, the number of unknown quantities appearing in a final expression could be largely reduced by introducing the new concept of a group body. In this process, both hydro-elasticity and hydrodynamic mutual interaction are considered. As a result, floating bodies that could not be previously calculated can be modeled as a three-dimensional frame structure and the response analysis in waves can be carried out without damaging the accuracy. The calculation result is used as the input data required for analyzing the structural fatigue locally during structural design of very large semi-submersibles in the 3,000 (m) class. This study can present a series of procedures between the response analysis of very large floating bodies in waves and the structural design. 11 refs., 14 figs., 1 tab.

  9. Differential photosynthetic and morphological adaptations to low light affect depth distribution of two submersed macrophytes in lakes.

    Science.gov (United States)

    Chen, Jianfeng; Cao, Te; Zhang, Xiaolin; Xi, Yilong; Ni, Leyi; Jeppesen, Erik

    2016-10-03

    To evaluate the relative importance of photosynthetic versus morphological adaptations of submersed macrophytes to low light intensity in lakes, rapid light curves (RLCs), morphological parameters, relative growth rate (RGR), clonal reproduction and abundance of two submersed macrophytes (Potamogeton maackianus and Vallisneria natans) were examined under 2.8%, 7.1%, 17.1% and 39.5% ambient light in a field and outdoor experimental study. The plants increased their initial slope of RLCs (α) and decreased their minimum saturating irradiance (E k ) and maximum relative electron transport rate (ETRm) of RLCs under low light stress, but V. natans was more sensitive in RLCs than P. maackianus. Accordingly, the RGR, plant height and abundance of P. maackianus were higher in the high light regimes (shallow water) but lower in the low light regimes than those of V. natans. At the 2.8% ambient light, V. natans produced ramets and thus fulfilled its population expansion, in contrast to P. maackianus. The results revealed that P. maackianus as a canopy-former mainly elongated its shoot length towards the water surface to compensate for the low light conditions, however, it became limited in severe low light stress conditions. V. natans as a rosette adapted to low light stress mainly through photosynthetic adjustments and superior to severely low light than shoot elongation.

  10. Double twist : Can-K's electric submersible twin screw pump is designed to handle the nastiest crudes

    Energy Technology Data Exchange (ETDEWEB)

    Byfield, M.

    2010-12-15

    This article described the Can-K Group of Companies' electric submersible twin screw pump (ESTSP) designed for pumping heavy crudes with high levels of asphaltenes, hydrogen sulphide, wax, and methane. The technology was awarded the 2010 winner of best production technology for a company with fewer than 100 employees. The ESTSP can pump at a greater depth than other lift technologies. The design challenges included making the pump small enough to fit inside the well casing while also able to generate the high pressures necessary for pumping heavy oil. The ESTSP can compete directly against other lift technologies, including electric submersible pumps (ESPs). In the design, two shafts are separated by a timing gear. Each shaft has short sections of interlocking screws that do not touch, which lessens tension and the need for torque, lowering electricity consumption. The ESTSP is more efficient than ESP systems, particularly in more viscous mediums with high gas-to-oil ratios. The positive displacement pump interprets only volume and does not distinguish between gas and oil, functioning with gas content up to 97 percent. ESTSP can also handle more sand than ESP because it does not rely on centrifugal force. A patented screw design also helps prevent pump seizure resulting from sand and other solids. The pump uses downhole electric motors from other manufacturers. The inherent efficiencies of twin screw pumps give the technology the potential to replace conventional ESPs. 2 figs.

  11. Generic phylogeny, historical biogeography and character evolution of the cosmopolitan aquatic plant family Hydrocharitaceae.

    Science.gov (United States)

    Chen, Ling-Yun; Chen, Jin-Ming; Gituru, Robert Wahiti; Wang, Qing-Feng

    2012-03-10

    Hydrocharitaceae is a fully aquatic monocot family, consists of 18 genera with approximately 120 species. The family includes both fresh and marine aquatics and exhibits great diversity in form and habit including annual and perennial life histories; submersed, partially submersed and floating leaf habits and linear to orbicular leaf shapes. The family has a cosmopolitan distribution and is well represented in the Tertiary fossil record in Europe. At present, the historical biogeography of the family is not well understood and the generic relationships remain controversial. In this study we investigated the phylogeny and biogeography of Hydrocharitaceae by integrating fossils and DNA sequences from eight genes. We also conducted ancestral state reconstruction for three morphological characters. Phylogenetic analyses produced a phylogeny with most branches strongly supported by bootstrap values greater than 95 and Bayesian posterior probability values of 1.0. Stratiotes is the first diverging lineage with the remaining genera in two clades, one clade consists of Lagarosiphon, Ottelia, Blyxa, Apalanthe, Elodea and Egeria; and the other consists of Hydrocharis-Limnobium, Thalassia, Enhalus, Halophila, Najas, Hydrilla, Vallisneria, Nechamandra and Maidenia. Biogeographic analyses (DIVA, Mesquite) and divergence time estimates (BEAST) resolved the most recent common ancestor of Hydrocharitaceae as being in Asia during the Late Cretaceous and Palaeocene (54.7-72.6 Ma). Dispersals (including long-distance dispersal and migrations through Tethys seaway and land bridges) probably played major roles in the intercontinental distribution of this family. Ancestral state reconstruction suggested that in Hydrocharitaceae evolution of dioecy is bidirectional, viz., from dioecy to hermaphroditism, and from hermaphroditism to dioecy, and that the aerial-submerged leaf habit and short-linear leaf shape are the ancestral states. Our study has shed light on the previously controversial

  12. Temporal changes in spatial patterns of submersed macrophytes in two impounded reaches of the Upper Mississippi River, USA, 1998-2009

    Science.gov (United States)

    De Jager, Nathan R.; Yin, Yao

    2011-01-01

    We examined temporal changes in spatial patterns of submersed aquatic macrophytes during a recent three-fold increase in macrophyte abundance and in response to the cumulative effects of management actions (island construction and water level management) and changes in regional environmental conditions (turbidity) in two navigation pools of the Upper Mississippi River, Pool 8 (managed) and Pool 13 (unmanaged). We used cross-correlograms to quantify changes in the degree and range of spatial correlation between submersed macrophytes and depth across the impounded portions of the two pools from 1998-2009. Along with increases in abundance, we observed gradual expansion of submersed macrophytes into deeper water in both pools. However, we detected no temporal change in spatial patterns in Pool 13, where the range of spatial correlation was ~ 1500-2500 m in length in the downriver direction and ~ 500-1000 m in length in the crossriver direction. We initially detected similar ranges of spatial correlation in Pool 8, but over time the range of correlation in the cross river direction increased from ~ 500 m in 1998 to ~ 2000 m by 2009. Thus, the expansion of submersed macrophytes into deeper water areas in Pool 8 appears to have occurred in the cross-river direction and led to increases in patch size and a more symmetrical patch configuration. Hence, very similar temporal changes in submersed macrophyte abundance corresponded with different diffusion dynamics and spatial patterns in the two pools. We hypothesize that management actions altered spatial patterns of depth, water flow and/or wind fetch and led to the differences in spatial patterns reported here.

  13. Stochastic dynamic response analysis of a floating vertical-axis wind turbine with a semi-submersible floater

    DEFF Research Database (Denmark)

    Wang, Kai; Moan, Torgeir; Hansen, Martin Otto Laver

    2016-01-01

    Floating vertical-axis wind turbines (FVAWTs) provide the potential for utilizing offshore wind resources in moderate and deep water because of their economical installation and maintenance. Therefore, it is important to assess the performance of the FVAWT concept. This paper presents a stochastic...... on the response is demonstrated by comparing the floating wind turbine with the equivalent land-based wind turbine. Additionally, by comparing the behaviour of FVAWTs with flexible and rigid rotors, the effect of rotor flexibility is evaluated. Furthermore, the FVAWT is also investigated in the parked condition...... dynamic response analysis of a 5MW FVAWT based on fully coupled nonlinear time domain simulations. The studied FVAWT, which is composed of a Darrieus rotor and a semi-submersible floater, is subjected to various wind and wave conditions. The global motion, structural response and mooring line tension...

  14. Expression conservation within the circadian clock of a monocot: natural variation at barley Ppd-H1 affects circadian expression of flowering time genes, but not clock orthologs.

    Science.gov (United States)

    Campoli, Chiara; Shtaya, Munqez; Davis, Seth J; von Korff, Maria

    2012-06-21

    The circadian clock is an endogenous mechanism that coordinates biological processes with daily changes in the environment. In plants, circadian rhythms contribute to both agricultural productivity and evolutionary fitness. In barley, the photoperiod response regulator and flowering-time gene Ppd-H1 is orthologous to the Arabidopsis core-clock gene PRR7. However, relatively little is known about the role of Ppd-H1 and other components of the circadian clock in temperate crop species. In this study, we identified barley clock orthologs and tested the effects of natural genetic variation at Ppd-H1 on diurnal and circadian expression of clock and output genes from the photoperiod-response pathway. Barley clock orthologs HvCCA1, HvGI, HvPRR1, HvPRR37 (Ppd-H1), HvPRR73, HvPRR59 and HvPRR95 showed a high level of sequence similarity and conservation of diurnal and circadian expression patterns, when compared to Arabidopsis. The natural mutation at Ppd-H1 did not affect diurnal or circadian cycling of barley clock genes. However, the Ppd-H1 mutant was found to be arrhythmic under free-running conditions for the photoperiod-response genes HvCO1, HvCO2, and the MADS-box transcription factor and vernalization responsive gene Vrn-H1. We suggest that the described eudicot clock is largely conserved in the monocot barley. However, genetic differentiation within gene families and differences in the function of Ppd-H1 suggest evolutionary modification in the angiosperm clock. Our data indicates that natural variation at Ppd-H1 does not affect the expression level of clock genes, but controls photoperiodic output genes. Circadian control of Vrn-H1 in barley suggests that this vernalization responsive gene is also controlled by the photoperiod-response pathway. Structural and functional characterization of the barley circadian clock will set the basis for future studies of the adaptive significance of the circadian clock in Triticeae species.

  15. Construction of high quality Gateway™ entry libraries and their application to yeast two-hybrid for the monocot model plant Brachypodium distachyon

    Directory of Open Access Journals (Sweden)

    Kumimoto Roderick W

    2011-05-01

    Full Text Available Abstract Background Monocots, especially the temperate grasses, represent some of the most agriculturally important crops for both current food needs and future biofuel development. Because most of the agriculturally important grass species are difficult to study (e.g., they often have large, repetitive genomes and can be difficult to grow in laboratory settings, developing genetically tractable model systems is essential. Brachypodium distachyon (hereafter Brachypodium is an emerging model system for the temperate grasses. To fully realize the potential of this model system, publicly accessible discovery tools are essential. High quality cDNA libraries that can be readily adapted for multiple downstream purposes are a needed resource. Additionally, yeast two-hybrid (Y2H libraries are an important discovery tool for protein-protein interactions and are not currently available for Brachypodium. Results We describe the creation of two high quality, publicly available Gateway™ cDNA entry libraries and their derived Y2H libraries for Brachypodium. The first entry library represents cloned cDNA populations from both short day (SD, 8/16-h light/dark and long day (LD, 20/4-h light/dark grown plants, while the second library was generated from hormone treated tissues. Both libraries have extensive genome coverage (~5 × 107 primary clones each and average clone lengths of ~1.5 Kb. These entry libraries were then used to create two recombination-derived Y2H libraries. Initial proof-of-concept screens demonstrated that a protein with known interaction partners could readily re-isolate those partners, as well as novel interactors. Conclusions Accessible community resources are a hallmark of successful biological model systems. Brachypodium has the potential to be a broadly useful model system for the grasses, but still requires many of these resources. The Gateway™ compatible entry libraries created here will facilitate studies for multiple user

  16. Antioxidative response of the three macrophytes Ceratophyllum demersum, Egeria densa, and Hydrilla verticillata to a time dependent exposure of cell-free crude extracts containing three microcystins from cyanobacterial blooms of Lake Amatitlán, Guatemala.

    Science.gov (United States)

    Romero-Oliva, Claudia Suseth; Contardo-Jara, Valeska; Pflugmacher, Stephan

    2015-06-01

    Microcystins (MCs) produced by cyanobacteria in natural environments are a potential risk to the integrity of ecosystems. In this study, the effects of cyanobacterial cell-free crude extracts from a Microcystis aeruginosa bloom containing three MC-congeners MC-LR, -RR, and -YR at environmental relevant concentrations of 49.3±2.9, 49.8±5.9, and 6.9±3.8μg/L, respectively, were evaluated on Ceratophyllum demersum (L.), Egeria densa (Planch.), and Hydrilla verticillata (L.f.). Effects on photosynthetic pigments (total chlorophyll (chl), chl a, chl b, and carotenoids), enzymatic defense led by catalase (CAT), peroxidase (POD) and glutathione reductase (GR), and biotransformation enzyme glutathione S-transferase (GST) were measured after 1, 4, and 8h and after 1, 3, 7, and 14 days of exposure. Results show that in all exposed macrophytes, photosynthetic pigments were negatively affected. While chl a and total chl decreased with increasing exposure time, a parallel increase in chl b was observed after 8h. Concomitant increase of ∼5, 16, and 34% of antioxidant carotenoid concentration in exposed C. demersum, E. densa, and H. verticillata, respectively, was also displayed. Enzymatic antioxidant defense systems in all exposed macrophytes were initiated within the first hour of exposure. In exposed E. densa, highest values of CAT and GR activities were observed after 4 and 8h, respectively, while in exposed H. verticillata highest value of POD activity was observed after 8h. An early induction with a significant increase of biotransformation enzyme GST was observed in E. densa after 4h and in C. demersum and H. verticillata after 8h. These results are the first to show rapid induction of stress and further possible MC biotransformation (based on the activation of GST enzymatic activity included in MC metabolization during the biotransformation mechanism) in macrophytes exposed to crude extract containing a mixture of MCs. Copyright © 2015 Elsevier B.V. All rights

  17. Central Experimental Oculina Research Reserve, Oculina Banks Clelia Dive 612 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  18. Framing 100-year overflowing and overtopping marine submersion hazard resulting from the propagation of 100-year joint hydrodynamic conditions

    Science.gov (United States)

    Nicolae Lerma, A.; Bulteau, T.; Elineau, S.; Paris, F.; Pedreros, R.

    2016-12-01

    Marine submersion is an increasing concern for coastal cities as urban development reinforces their vulnerabilities while climate change is likely to foster the frequency and magnitude of submersions. Characterising the coastal flooding hazard is therefore of paramount importance to ensure the security of people living in such places and for coastal planning. A hazard is commonly defined as an adverse phenomenon, often represented by a magnitude of a variable of interest (e.g. flooded area), hereafter called response variable, associated with a probability of exceedance or, alternatively, a return period. Characterising the coastal flooding hazard consists in finding the correspondence between the magnitude and the return period. The difficulty lies in the fact that the assessment is usually performed using physical numerical models taking as inputs scenarios composed by multiple forcing conditions that are most of the time interdependent. Indeed, a time series of the response variable is usually not available so we have to deal instead with time series of forcing variables (e.g. water level, waves). Thus, the problem is twofold: on the one hand, the definition of scenarios is a multivariate matter; on the other hand, it is tricky and approximate to associate the resulting response, being the output of the physical numerical model, to the return period defined for the scenarios. In this study, we illustrate the problem on the district of Leucate, located in the French Mediterranean coast. A multivariate extreme value analysis of waves and water levels is performed offshore using a conditional extreme model, then two different methods are used to define and select 100-year scenarios of forcing variables: one based on joint exceedance probability contours, a method classically used in coastal risks studies, the other based on environmental contours, which are commonly used in the field of structure design engineering. We show that these two methods enable one to

  19. Experimental study on vortex-induced motions of a semi-submersible with square columns and pontoons at different draft conditions and current incidences

    Directory of Open Access Journals (Sweden)

    Mingyue Liu

    2017-05-01

    Full Text Available The Vortex-induced Motions (VIM phenomenon of semi-submersibles is relevant for the fatigue life of moorings and risers. Model tests regarding the VIM behavior of a semi-submersible with four square columns were conducted in order to investigate the effects of the current incidence and the aspect ratio of the immerged column. The experimental results show that the largest transverse amplitudes are around 70% of the column width at 30° and 45° incidences in a range of reduced velocities from 5 to 8 when the aspect ratio of the immerged column is 1.90. The largest yaw motion occurs at 0° incidence with the peak value around 4.5°. Similar characteristics of the VIM response are observed for the semi-submersible with aspect ratios of 1.90 and 1.73. When the aspect ratio decreases 50% to 0.87, 30% decrease in the peak transverse amplitudes can be seen.

  20. Investigation on flow pattern by submersible mechanical aerator aused in anaerobic-aerobic tank. Kenki koki ken'yo suichu aerator ni yoru sonai ryudo no chosa kensho

    Energy Technology Data Exchange (ETDEWEB)

    Ogasawara, M; Inoue, H; Kamei, T; Kato, N [Ebara Corp., Tokyo (Japan)

    1994-01-20

    As explained in the present report, flow pattern was verified in a submersible aerator tank for both anaerobic and aerobic wastewater treatment (submersible plant for the mechanical agitation and aeration). The verification was made in a water passage of the sewage treatment plant. The flowing was conditioned as per the measurement of both flow velocity and activated sludge concentration. The submersible aerator was installed so that balance might be kept in ventilating pressure between it and the diffusing plate. The flowing on the tank bottom was stabilized by installing a special guide at the outlet of aerator. The result was as follows: in both tanks during the anaerobic operation, the flow velocity was 0.15m/s as a whole and higher than the standard of 0.1m/s on the tank bottom. Under the tank top and at the middle of tank height, the flow velocity is lower than that on the tank bottom and the intake of dissolved oxygen is weak. In both tanks during the aerobic operation, the flow velocity as a whole is higher than that during the anaerobic operation. It is attributable to the airlift effect. The flow pattern during the aerobic operation is characterized by the flow which is generated, by airlift effect, under the tank top toward the wall. Then, that flow effectively works for the flowing on the tank bottom. Hardly dispersed, the pollutant concentration indicates that the flowing is sufficient in the tank. 4 refs., 6 figs., 3 tabs.

  1. Deep-water feeding and behavioral plasticity in Manta birostris revealed by archival tags and submersible observations.

    Science.gov (United States)

    Stewart, Joshua D; Hoyos-Padilla, Edgar Mauricio; Kumli, Katherine R; Rubin, Robert D

    2016-10-01

    Foraging drives many fundamental aspects of ecology, and an understanding of foraging behavior aids in the conservation of threatened species by identifying critical habitats and spatial patterns relevant to management. The world's largest ray, the oceanic manta (Manta birostris) is poorly studied and threatened globally by targeted fisheries and incidental capture. Very little information is available on the natural history, ecology and behavior of the species, complicating management efforts. This study provides the first data on the diving behavior of the species based on data returned from six tagged individuals, and an opportunistic observation from a submersible of a manta foraging at depth. Pop-off archival satellite tags deployed on mantas at the Revillagigedo Archipelago, Mexico recorded seasonal shifts in diving behavior, likely related to changes in the location and availability of zooplankton prey. Across seasons, mantas spent a large proportion of their time centered around the upper limit of the thermocline, where zooplankton often aggregate. Tag data reveal a gradual activity shift from surface waters to 100-150m across the tagging period, possibly indicating a change in foraging behavior from targeting surface-associated zooplankton to vertical migrators. The depth ranges accessed by mantas in this study carry variable bycatch risks from different fishing gear types. Consequently, region-specific data on diving behavior can help inform local management strategies that reduce or mitigate bycatch of this vulnerable species. Copyright © 2016 Elsevier GmbH. All rights reserved.

  2. Taxonomic research on deep-sea macrofauna in the South China Sea using the Chinese deep-sea submersible Jiaolong.

    Science.gov (United States)

    Li, Xinzheng

    2017-07-01

    This paper reviews the taxonomic and biodiversity studies of deep-sea invertebrates in the South China Sea based on the samples collected by the Chinese manned deep-sea submersible Jiaolong. To date, 6 new species have been described, including the sponges Lophophysema eversa, Saccocalyx microhexactin and Semperella jiaolongae as well as the crustaceans Uroptychus jiaolongae, Uroptychus spinulosus and Globospongicola jiaolongi; some newly recorded species from the South China Sea have also been reported. The Bathymodiolus platifrons-Shinkaia crosnieri deep-sea cold seep community has been reported by Li (2015), as has the mitochondrial genome of the glass sponge L. eversa by Zhang et al. (2016). The population structures of two dominant species, the shrimp Shinkaia crosnieri and the mussel Bathymodiolus platifrons, from the cold seep Bathymodiolus platifrons-Shinkaia crosnieri community in the South China Sea and the hydrothermal vents in the Okinawa Trough, were compared using molecular analysis. The systematic position of the shrimp genus Globospongicola was discussed based on 16S rRNA gene sequences. © 2017 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  3. A Submersible, Off-Axis Holographic Microscope for Detection of Microbial Motility and Morphology in Aqueous and Icy Environments.

    Science.gov (United States)

    Lindensmith, Christian A; Rider, Stephanie; Bedrossian, Manuel; Wallace, J Kent; Serabyn, Eugene; Showalter, G Max; Deming, Jody W; Nadeau, Jay L

    2016-01-01

    Sea ice is an analog environment for several of astrobiology's near-term targets: Mars, Europa, Enceladus, and perhaps other Jovian or Saturnian moons. Microorganisms, both eukaryotic and prokaryotic, remain active within brine channels inside the ice, making it unnecessary to penetrate through to liquid water below in order to detect life. We have developed a submersible digital holographic microscope (DHM) that is capable of resolving individual bacterial cells, and demonstrated its utility for immediately imaging samples taken directly from sea ice at several locations near Nuuk, Greenland. In all samples, the appearance and motility of eukaryotes were conclusive signs of life. The appearance of prokaryotic cells alone was not sufficient to confirm life, but when prokaryotic motility occurred, it was rapid and conclusive. Warming the samples to above-freezing temperatures or supplementing with serine increased the number of motile cells and the speed of motility; supplementing with serine also stimulated chemotaxis. These results show that DHM is a useful technique for detection of active organisms in extreme environments, and that motility may be used as a biosignature in the liquid brines that persist in ice. These findings have important implications for the design of missions to icy environments and suggest ways in which DHM imaging may be integrated with chemical life-detection suites in order to create more conclusive life detection packages.

  4. Submersible microbial desalination cell for simultaneous ammonia recovery and electricity production from anaerobic reactors containing high levels of ammonia

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2015-01-01

    High ammonia concentration in anaerobic reactors can seriously inhibit the anaerobic digestion process. In this study, a submersible microbial desalination cell (SMDC) was developed as an innovative method to lower the ammonia level in a continuous stirred tank reactor (CSTR) by in situ ammonia...... recovery and electricity production. In batch experiment, the ammonia concentration in the CSTR decreased from 6 to 0.7g-N/L during 30days, resulting in an average recovery rate of 80g-N/m2/d. Meanwhile, a maximum power density of 0.71±0.5W/m2 was generated at 2.85A/m2. Both current driven NH4+ migration...... and free NH3 diffusion were identified as the mechanisms responsible for the ammonia transportation. With an increase in initial ammonia concentration and a decrease in external resistance, the SMDC performance was enhanced. In addition, the coexistence of other cations in CSTR or cathode had no negative...

  5. Submersible microbial desalination cell for simultaneous ammonia recovery and electricity production from anaerobic reactors containing high levels of ammonia.

    Science.gov (United States)

    Zhang, Yifeng; Angelidaki, Irini

    2015-02-01

    High ammonia concentration in anaerobic reactors can seriously inhibit the anaerobic digestion process. In this study, a submersible microbial desalination cell (SMDC) was developed as an innovative method to lower the ammonia level in a continuous stirred tank reactor (CSTR) by in situ ammonia recovery and electricity production. In batch experiment, the ammonia concentration in the CSTR decreased from 6 to 0.7 g-N/L during 30 days, resulting in an average recovery rate of 80 g-N/m(2)/d. Meanwhile, a maximum power density of 0.71±0.5 W/m(2) was generated at 2.85 A/m(2). Both current driven NH4(+) migration and free NH3 diffusion were identified as the mechanisms responsible for the ammonia transportation. With an increase in initial ammonia concentration and a decrease in external resistance, the SMDC performance was enhanced. In addition, the coexistence of other cations in CSTR or cathode had no negative effect on the ammonia transportation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Mechanistic Drifting Forecast Model for A Small Semi-Submersible Drifter Under Tide-Wind-Wave Conditions

    Science.gov (United States)

    Zhang, Wei-Na; Huang, Hui-ming; Wang, Yi-gang; Chen, Da-ke; Zhang, lin

    2018-03-01

    Understanding the drifting motion of a small semi-submersible drifter is of vital importance regarding monitoring surface currents and the floating pollutants in coastal regions. This work addresses this issue by establishing a mechanistic drifting forecast model based on kinetic analysis. Taking tide-wind-wave into consideration, the forecast model is validated against in situ drifting experiment in the Radial Sand Ridges. Model results show good performance with respect to the measured drifting features, characterized by migrating back and forth twice a day with daily downwind displacements. Trajectory models are used to evaluate the influence of the individual hydrodynamic forcing. The tidal current is the fundamental dynamic condition in the Radial Sand Ridges and has the greatest impact on the drifting distance. However, it loses its leading position in the field of the daily displacement of the used drifter. The simulations reveal that different hydrodynamic forces dominate the daily displacement of the used drifter at different wind scales. The wave-induced mass transport has the greatest influence on the daily displacement at Beaufort wind scale 5-6; while wind drag contributes mostly at wind scale 2-4.

  7. A Submersible, Off-Axis Holographic Microscope for Detection of Microbial Motility and Morphology in Aqueous and Icy Environments.

    Directory of Open Access Journals (Sweden)

    Christian A Lindensmith

    Full Text Available Sea ice is an analog environment for several of astrobiology's near-term targets: Mars, Europa, Enceladus, and perhaps other Jovian or Saturnian moons. Microorganisms, both eukaryotic and prokaryotic, remain active within brine channels inside the ice, making it unnecessary to penetrate through to liquid water below in order to detect life. We have developed a submersible digital holographic microscope (DHM that is capable of resolving individual bacterial cells, and demonstrated its utility for immediately imaging samples taken directly from sea ice at several locations near Nuuk, Greenland. In all samples, the appearance and motility of eukaryotes were conclusive signs of life. The appearance of prokaryotic cells alone was not sufficient to confirm life, but when prokaryotic motility occurred, it was rapid and conclusive. Warming the samples to above-freezing temperatures or supplementing with serine increased the number of motile cells and the speed of motility; supplementing with serine also stimulated chemotaxis. These results show that DHM is a useful technique for detection of active organisms in extreme environments, and that motility may be used as a biosignature in the liquid brines that persist in ice. These findings have important implications for the design of missions to icy environments and suggest ways in which DHM imaging may be integrated with chemical life-detection suites in order to create more conclusive life detection packages.

  8. Creating Student Engagement Through Immersion: Exploring the MT6 Shipwreck in Puget Sound via Submersible, Using a Team Challenge Format

    Science.gov (United States)

    Sarason, C. P.; Hartzler, R.; Anderson, A.

    2016-02-01

    Educational literature has many stories describing the "aha" moment that teachers are privileged to observe: a student who suddenly grasps a concept (ding!), dives into an activity (whee!) or works tirelessly to complete a complicated project (wow!). Designing moments like these for students can be one of the great joys of teaching. Experiencing such a moment can have a lasting impact on student engagement and motivation, and is the underlying rationale for the importance of creating a wide array of outreach efforts, from field work to telepresence activities.During the spring of 2015, OceanGate Foundation and Seattle Central College partnered on a pilot program to design a program that had this kind of impact and created the Open The Oceans Challenge. Student teams responded to our Request for Proposal (RFP), which was centered around the exploration of a shipwreck in 150 meters of water just off the Seattle waterfront, the MT-6. Students spent a significant amount of time crafting their proposals and reported that they enjoyed the process of writing the proposal as a team. The two winning teams accompanied us on a series of submersible dives performed by OceanGate, Inc. and worked up the results afterward. In addition to researching the MT-6 wreck and documenting what they found, students were able to do basic observational research on the wreck, providing sonar and photographic data that will help form the basis of future expeditions to this site.We report on lessons learned from this pilot — the impact for the small set of students involved in this project was profound, but how can we expand the reach of such activities? Results from this experience suggest that providing a highly engaging topic and expedition may not be enough to inspire an "aha" moment that creates lasting engagement; the scaffolding and mentorship that surrounds a rich experience is also critical.

  9. The effect of submersion denture base acrylic resin in a betel leaf ekstract solution against growth Candida albicans

    Directory of Open Access Journals (Sweden)

    Andi Izham

    2016-06-01

    Full Text Available Denture base is a protesa which replace some or all of the lost original teeth and surrounding tissues. The Pupose of making protesa is for restore the function, appearance, comfort and impaired health result lost teeth. One part of the denture base is base plate. Microorganisms are often found in the oral cavity is Candida albicans (C.albicans approximately 40% in the oral cavity.C.albicans can penetrate the acrylic resin that can infect the soft tissue and is the cause of denture stomatitis therefore the disinfection of denture base is a important factor that must be done. In general betel leaves contant up to 4.2% essential oil compounds and phenyl propanoid and tannin. These compounds is a antimicroba and antifungal which can inhibit the growth of several type of bacteria among others Escherichia coli, Salmonella sp, Staphylococcus aurens, Klebstella, Pasteurella and can turn off the C.albicans. The purpose of the research is to determine how the effect of submersion denture base acrylic resin in a betel leaf ekstract solution against growth C.albicans.Type of research is an experimental laboratory with a longitudinal design (follow-up study. The sampling method used is total sampling. The results showed that the number of C.albicans colonies n denture base acrylic resin which soaked betel leaf extract solution that the dilution 10-1  with consentration 2.5% total colony count is 2 and the results 2.0 x 101 CFU/ml, on a control solution that the dilution 10-2 total colony 355 and the result 3.55 x 104 CFU/ml, that the dilution  10-3 total colony 62 and the result 6.2 x 104 CFU/ml.

  10. Submersible microbial fuel cell sensor for monitoring microbial activity and BOD in groundwater: Focusing on impact of anodic biofilm on sensor applicability

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2011-01-01

    was required for application of the sensor for microbial activity measurement, while biofilm‐colonized anode was needed for utilizing the sensor for BOD content measurement. The current density of SUMFC sensor equipped with a biofilm‐colonized anode showed linear relationship with BOD content, to up to 250 mg......A sensor, based on a submersible microbial fuel cell (SUMFC), was developed for in situ monitoring of microbial activity and biochemical oxygen demand (BOD) in groundwater. Presence or absence of a biofilm on the anode was a decisive factor for the applicability of the sensor. Fresh anode...

  11. Long-term trends in submersed aquatic vegetation (SAV) in Chesapeake Bay, USA, related to water quality

    Science.gov (United States)

    Orth, Robert J.; Williams, Michael R.; Marion, Scott R.; Wilcox, David J.; Carruthers, Tim J.B.; Moore, Kenneth A.; Kemp, W.M.; Dennison, William C.; Rybicki, Nancy B.; Peter Bergstrom,; Batiuk, Richard A.

    2010-01-01

    Chesapeake Bay supports a diverse assemblage of marine and freshwater species of submersed aquatic vegetation (SAV) whose broad distributions are generally constrained by salinity. An annual aerial SAV monitoring program and a bi-monthly to monthly water quality monitoring program have been conducted throughout Chesapeake Bay since 1984. We performed an analysis of SAV abundance and up to 22 environmental variables potentially influencing SAV growth and abundance (1984-2006). Historically, SAV abundance has changed dramatically in Chesapeake Bay, and since 1984, when SAV abundance was at historic low levels, SAV has exhibited complex changes including long-term (decadal) increases and decreases, as well as some large, single-year changes. Chesapeake Bay SAV was grouped into three broad-scale community-types based on salinity regime, each with their own distinct group of species, and detailed analyses were conducted on these three community-types as well as on seven distinct case-study areas spanning the three salinity regimes. Different trends in SAVabundance were evident in the different salinity regimes. SAV abundance has (a) continually increased in the low-salinity region; (b) increased initially in the medium-salinity region, followed by fluctuating abundances; and (c) increased initially in the high-salinity region, followed by a subsequent decline. In all areas, consistent negative correlations between measures of SAV abundance and nitrogen loads or concentrations suggest that meadows are responsive to changes in inputs of nitrogen. For smaller case-study areas, different trends in SAV abundance were also noted including correlations to water clarity in high-salinity case-study areas, but nitrogen was highly correlated in all areas. Current maximum SAV coverage for almost all areas remain below restoration targets, indicating that SAV abundance and associated ecosystem services are currently limited by continued poor water quality, and specifically high

  12. Software-In-the-Loop based Modeling and Simulation of Unmanned Semi-submersible Vehicle for Performance Verification of Autonomous Navigation

    Science.gov (United States)

    Lee, Kwangkook; Jeong, Mijin; Kim, Dong Hun

    2017-12-01

    Since an unmanned semi-submersible is mainly used for the purpose of carrying out dangerous missions in the sea, it is possible to work in a region where it is difficult to access due to safety reasons. In this study, an USV hull design was determined using Myring hull profile, and reinforcement work was performed by designing and implementing inner stiffener member for 3D printing. In order to simulate a sea state 5.0 or more at sea, which is difficult to implement in practice, a regular and irregular wave equation was implemented in Matlab / Simulink. We performed modeling and simulation of semi - submersible simulation based on DMWorks considering the rolling motion in wave. To verify and improve unpredicted errors, we implemented a numeric and physical simulation model of the USV based on software-in-the-loop (SIL) method. This simulation allows shipbuilders to participate in new value-added markets such as engineering, procurement, construction, installation, commissioning, operation, and maintenance for the USV.

  13. Using Cable Suspended Submersible Pumps to Reduce Production Costs to Increase Ultimate Recovery in the Red Mountain Field of the San Juan Basin Region

    Energy Technology Data Exchange (ETDEWEB)

    Don L. Hanosh

    2006-08-15

    A joint venture between Enerdyne LLC, a small independent oil and gas producer, and Pumping Solutions Inc., developer of a low volume electric submersible pump, suspended from a cable, both based in Albuquerque, New Mexico, has re-established marginal oil production from Red Mountain Oil Field, located in the San Juan Basin, New Mexico by working over 17 existing wells, installing cable suspended submersible pumps ( Phase I ) and operating the oil field for approximately one year ( Phase II ). Upon the completion of Phases I and II ( Budget Period I ), Enerdyne LLC commenced work on Phase III which required additional drilling in an attempt to improve field economics ( Budget Period II ). The project was funded through a cooperative 50% cost sharing agreement between Enerdyne LLC and the National Energy Technology Laboratory (NETL), United States Department of Energy, executed on April 16, 2003. The total estimated cost for the two Budget Periods, of the Agreement, was $1,205,008.00 as detailed in Phase I, II & III Authorization for Expenditures (AFE). This report describes tasks performed and results experienced by Enerdyne LLC during the three phases of the cooperative agreement.

  14. Coexistence of fish species in a large lowland river: food niche partitioning between small-sized percids, cyprinids and sticklebacks in submersed macrophytes.

    Science.gov (United States)

    Dukowska, Małgorzata; Grzybkowska, Maria

    2014-01-01

    In the spring and summer of each year, large patches of submersed aquatic macrophytes overgrow the bottom of the alluvial Warta River downstream of a large dam reservoir owing to water management practices. Environmental variables, macroinvertebrates (zoobenthos and epiphytic fauna, zooplankton) and fish abundance and biomass were assessed at this biologically productive habitat to learn intraseasonal dynamics of food types, and their occurrence in the gut contents of small-sized roach, dace, perch, ruffe and three-spined stickleback. Gut fullness coefficient, niche breadth and niche overlap indicated how the fishes coexist in the macrophytes. Chironomidae dominated in the diet of the percids. However, ruffe consumed mostly benthic chironomids, while perch epiphytic chironomids and zooplankton. The diet of dace resembled that in fast flowing water although this rheophilic species occurred at unusual density there. The generalist roach displayed the lowest gut fullness coefficient values and widest niche breadth; consequently, intraspecific rather than interspecific competition decided the fate of roach. Three-spined stickleback differed from the other fishes by consuming epiphytic simuliids and fish eggs. The diet overlap between fishes reaching higher gut fullness coefficient values was rather low when the food associated with the submersed aquatic macrophytes was most abundant; this is congruent with the niche overlap hypothesis that maximal tolerable niche overlap can be higher in less intensely competitive conditions.

  15. Spatial and temporal relationships between the invasive snail Bithynia tentaculata and submersed aquatic vegetation in Pool 8 of the Upper Mississippi River

    Science.gov (United States)

    Weeks, Alicia M.; DeJager, Nathan R.; Haro, Roger J.; Sandland, Greg J.

    2017-01-01

    Bithynia tentaculata is an invasive snail that was first reported in Lake Michigan in 1871 and has since spread throughout a number of freshwater systems of the USA. This invasion has been extremely problematic in the Upper Mississippi River as the snails serve as intermediate hosts for several trematode parasites that have been associated with waterfowl mortality in the region. This study was designed to assess the abundance and distribution of B. tentaculata relative to submersed aquatic vegetation as macrophytes provide important nesting and food resources for migrating waterfowl. Temporal changes in both vegetation and snail densities were compared between 2007 and 2015. Between these years, B. tentaculata densities have nearly quadrupled despite minor changes in vegetation abundance, distribution and composition. Understanding the spatial distribution of B. tentaculata in relation to other habitat features, including submersed vegetation, and quantifying any further changes in the abundance and distribution of B. tentaculata over time will be important for better identifying areas of risk for disease transmission to waterfowl.

  16. Study on operation conditions and an operation system of a nuclear powered submersible research vessel, 'report of working group on application of a very small nuclear reactor to an ocean research'

    International Nuclear Information System (INIS)

    Ura, Tamaki; Takamasa, Tomoji; Nishimura, Hajime

    2001-07-01

    JAERI has studied on design of a nuclear powered submersible research vessel, which will navigate under sea mainly in the Arctic Ocean, as a part of the design activity of advanced marine reactors. This report describes operation conditions and an operating system of the vessel, which were discussed by the specialists of hull design, sound positioning, ship motions and oceanography, etc. The design conditions on ship motions for submersible vessels were surveyed considering regulations in our country, and ship motions were evaluated in the cases of underwater and surface navigations taking account of observation activities in the Arctic Ocean. The effect of ship motions on the compact nuclear reactor SCR was assessed. A submarine transponder system and an on-ice communication buoy system were examined as a positioning and communication system, supposing the activity under ice. The interval between transponders or communication buoys was recommended as 130 km. Procedures to secure safety of nuclear powered submersible research vessel were discussed according to accidents on the hull or the nuclear reactor. These results were reflected to the concept of the nuclear powered submersible research vessel, and subjects to be settled in the next step were clarified. (author)

  17. Study on operation conditions and an operation system of a nuclear powered submersible research vessel, 'report of working group on application of a very small nuclear reactor to an ocean research'

    Energy Technology Data Exchange (ETDEWEB)

    Ura, Tamaki [Tokyo Univ., Tokyo (Japan); Takamasa, Tomoji [Tokyo Univ. of Mercantile Marine, Tokyo (Japan); Nishimura, Hajime [Japan Marine Science and Technology Center, Yokosuka, Kanagawa (JP)] [and others

    2001-07-01

    JAERI has studied on design of a nuclear powered submersible research vessel, which will navigate under sea mainly in the Arctic Ocean, as a part of the design activity of advanced marine reactors. This report describes operation conditions and an operating system of the vessel, which were discussed by the specialists of hull design, sound positioning, ship motions and oceanography, etc. The design conditions on ship motions for submersible vessels were surveyed considering regulations in our country, and ship motions were evaluated in the cases of underwater and surface navigations taking account of observation activities in the Arctic Ocean. The effect of ship motions on the compact nuclear reactor SCR was assessed. A submarine transponder system and an on-ice communication buoy system were examined as a positioning and communication system, supposing the activity under ice. The interval between transponders or communication buoys was recommended as 130 km. Procedures to secure safety of nuclear powered submersible research vessel were discussed according to accidents on the hull or the nuclear reactor. These results were reflected to the concept of the nuclear powered submersible research vessel, and subjects to be settled in the next step were clarified. (author)

  18. Effect of Difference-frequency Forces on the Dynamics of a Semi-submersible Type FVAWT in Misaligned Wave-wind Condition

    DEFF Research Database (Denmark)

    Wang, Kai; Cheng, Zhengshun; Moan, Torgeir

    2015-01-01

    With increasing interests in the development of offshore floating vertical axis wind turbines (FVAWTs), a large amount of studies on the FVAWTs have been conducted. This paper focuses on evaluating the effect of second-order difference-frequency force on the dynamics of a 5 MW FVAWT in misaligned...... wave-wind condition. The studied FVAWT is composed of a 5 MW Darrieus rotor, a semi-submersible floater and a catenary mooring system. Fully coupled nonlinear time domain simulations were conducted using the state-of-art code Simo- Riflex-DMS. Several misaligned wave-wind conditions were selected...... to investigate the global dynamic responses of the FVAWT, such as the platform motions, structural responses and mooring line tensions. It has been found that the wave-wind misalignment does not significantly affect the mean values of the global responses since the global responses are primarily wind...

  19. Electricity generation and microbial community in response to short-term changes in stack connection of self-stacked submersible microbial fuel cell powered by glycerol

    DEFF Research Database (Denmark)

    Zhao, Nannan; Angelidaki, Irini; Zhang, Yifeng

    2017-01-01

    community. In this study, a self-stacked submersible microbial fuel cell (SSMFC) powered by glycerol was tested to elucidate this important issue. In series connection, the maximum voltage output reached to 1.15 V, while maximum current density was 5.73 mA in parallel. In both connections, the maximum power......Stack connection (i.e., in series or parallel) of microbial fuel cell (MFC) is an efficient way to boost the power output for practical application. However, there is little information available on short-term changes in stack connection and its effect on the electricity generation and microbial...... density increased with the initial glycerol concentration. However, the glycerol degradation was even faster in parallel connection. When the SSMFC was shifted from series to parallel connection, the reactor reached to a stable power output without any lag phase. Meanwhile, the anodic microbial community...

  20. LIGA 2. An improved computer code for the calculation of the local individual submersion dose in off-air plumes from nuclear facilities

    International Nuclear Information System (INIS)

    Rohloff, F.; Brunen, E.

    1981-08-01

    A model is presented to calculate the γ-submersion dose of persons which are exposed to off-air plumes. This model integrates the dose contributions of the spacial volume elements, taking into account the wheather dependent extension of the plume as well as γ-absorption and scattering in air. For data evaluation an essentially improved code LIGA II has been developed, leading to a higher accuracy due to an adequate application of Gauss integrations in MACRO-technique. The short-term propagation factors are calculated for a grid distance of 10-160 km with a logarithmic scale and for a 5 degree angular grid. As is shown by a sensitivity analysis, the mean values of the short-term propagation factors within a sector can be obtained by a simple Simpson-integration. These calculations have been performed explicitly for 10 degree and 30 degree sectors. (orig.) [de

  1. Intérêt de l'étude de la flore des diatomées du lieu de submersion dans le diagnostic de noyade

    Directory of Open Access Journals (Sweden)

    LUDES B.

    1996-04-01

    Full Text Available La recherche de diatomées dans les tissus de la victime pour contribuer au diagnostic de noyade doit être accompagnée de l'analyse d'un échantillon d'eau prélevé sur les lieux de précipitation ou de découverte du corps. Cet échantillon permet d'établir un inventaire représentatif de la flore du lieu de découverte ou de submersion, et d'effectuer les comparaisons avec les taxons trouvés dans les tissus. De plus, la détermination de taxons dominants dans l'échantillon d'eau peut avoir une valeur indicative du lieu de découverte.

  2. Generic phylogeny, historical biogeography and character evolution of the cosmopolitan aquatic plant family Hydrocharitaceae

    Directory of Open Access Journals (Sweden)

    Chen Ling-Yun

    2012-03-01

    Full Text Available Abstract Background Hydrocharitaceae is a fully aquatic monocot family, consists of 18 genera with approximately 120 species. The family includes both fresh and marine aquatics and exhibits great diversity in form and habit including annual and perennial life histories; submersed, partially submersed and floating leaf habits and linear to orbicular leaf shapes. The family has a cosmopolitan distribution and is well represented in the Tertiary fossil record in Europe. At present, the historical biogeography of the family is not well understood and the generic relationships remain controversial. In this study we investigated the phylogeny and biogeography of Hydrocharitaceae by integrating fossils and DNA sequences from eight genes. We also conducted ancestral state reconstruction for three morphological characters. Results Phylogenetic analyses produced a phylogeny with most branches strongly supported by bootstrap values greater than 95 and Bayesian posterior probability values of 1.0. Stratiotes is the first diverging lineage with the remaining genera in two clades, one clade consists of Lagarosiphon, Ottelia, Blyxa, Apalanthe, Elodea and Egeria; and the other consists of Hydrocharis-Limnobium, Thalassia, Enhalus, Halophila, Najas, Hydrilla, Vallisneria, Nechamandra and Maidenia. Biogeographic analyses (DIVA, Mesquite and divergence time estimates (BEAST resolved the most recent common ancestor of Hydrocharitaceae as being in Asia during the Late Cretaceous and Palaeocene (54.7-72.6 Ma. Dispersals (including long-distance dispersal and migrations through Tethys seaway and land bridges probably played major roles in the intercontinental distribution of this family. Ancestral state reconstruction suggested that in Hydrocharitaceae evolution of dioecy is bidirectional, viz., from dioecy to hermaphroditism, and from hermaphroditism to dioecy, and that the aerial-submerged leaf habit and short-linear leaf shape are the ancestral states. Conclusions

  3. Volcanic eruption of the mid-ocean ridge along the East Pacific Rise crest at 9°45-52'N: direct submersible observations of seafloor phenomena associated with an eruption event in April, 1991

    Science.gov (United States)

    Haymon, R.M.; Fornari, D.J.; Von Damm, Karen L.; Lilley, M.D.; Perfit, M.R.; Edmond, J.M.; Shanks, Wayne C.; Lutz, R.A.; Grebmeier, J.M.; Carbotte, S.; Wright, D.; McLaughlin, E.; Smith, M.; Beedle, N.; Olson, E.

    1993-01-01

    In April, 1991, we witnessed from the submersible Alvin a suite of previously undocumented seafloor phenomena accompanying an in-progress eruption of the mid-ocean ridge on the East Pacific Rise crest at 9°45′N–52′N. The volume of the eruption could not be precisely determined, although comparison of pre- and post-eruption SeaBeam bathymetry indicate that any changes in ridge crest morphology resulting from the eruption were < 10 m high.

  4. Pilot-scale submersed cultivation of R. microsporus var. oligosporus in thin stillage, a dry-grind corn-to-ethanol co-product

    Science.gov (United States)

    Erickson, Daniel Thomas

    An innovative process to add value to a corn-to-ethanol co-product, Thin stillage, was studied for pilot-scale viability. A 1500L bioreactor was designed, operated, and optimized to cultivate Rhizopus microsporus var. oligosporus via submersed fermentation in Thin Stillage. The biomass was harvested and processed into a feed suitable for storage and ultimately for animal feeding trials. Characterization of the biomass and feed trials revealed that there is substantial potential as a nutrient dense feed supplement with 41.1% protein, 26.3% fat, and metabolizable energy on s dried basis. The amino acid profile is superior to that of DDGS, with most notably 1.7% Lys on dried basis. This process produces a significantly more nutrient dense product than DDGS, and could increase water-reclaimation in a dry-grind corn to ethanol plant. Industrially it would replace the energy intensive process of converting thin stillage into syrup that adds only $10-25/ton to DDG, while maintaining production of DDG. Using thin stillage as used a growth media for R. microsporus var. oligosporus, should not only lead to saving in energy costs, but also generate a high-value co-product which could lead to economic gains. Also there is still unexplored potential of enzymes, chitin, and co-culturing to further add value.

  5. Study of Stage-wise Pressure Pulsation in an Electric Submersible Pump under Variable Frequency Operation at Shut-off Condition

    Science.gov (United States)

    Dhanasekaran, A.; Kumaraswamy, S.

    2018-01-01

    Pressure pulsation causes vibration in the Electric Submersible Pump (ESP) and affects the life and performance of its system. ESP systems are installed at depths ranging from a few meters to several hundred meters. Unlike pumps used on the surface, once they are installed they become inaccessible for maintenance or for any kind of diagnostic measurement that might be taken directly on them. Therefore a detailed knowledge of mean and fluctuating pressures is required to achieve an optimal pressure distribution inside the ESP. This paper presents the results of an experimental investigation of the stage-wise pulsating pressure in ESP at shut-off condition at different speeds. Experiments were conducted on a pump having five stages. A variable frequency drive was used to operate the pump at five different speeds. Piezoresistive transducers were mounted at each stage of ESP to capture the unsteady pressure signals. Fast Fourier Transformation was carried out on the pressure signals to convert into frequency domain and the spectra of pressure pulsation signals were analyzed. The obtained results indicated the existence of fundamental frequency corresponding to the speed of rotation times the number of impeller blades and of the whole series of harmonics of higher frequencies.

  6. Study of the influence of stable cadmium on the transfer of zinc-65 in an ecosystem irrigated by submersion (irrigated rice field)

    International Nuclear Information System (INIS)

    Myttenaere, C.; Merlini, M.; Dabin, P.; Mousny, J.M.; Pozzi, G.; Bittel, R.

    1975-01-01

    Irrigation water contains varying amounts of stable cadmium from industrial disposal. The presence of this element is capable of modifying the transfer of and affecting the mechanisms of absorption of zinc-65, a radionuclide which is discharged into water by nuclear power stations. This type of interaction between a nuclear contaminant and a conventional contaminant was studied in a rice-field irrigated by submersion. This ecosystem was reproduced under controlled 'mini-rice-field' conditions: the water was enriched in stable zinc (1 ppm) and in stable cadmium (2,5x10 -3 ; 50x10 -3 ppm) so as to reproduce the actual conditions; the stable zinc was traced by means of zinc-65. Fish (20 Carassius auratus L.) were introduced into each compartment of the ecosystem. Samples of irrigation water and surface water were taken during cultivation, and at the end of cultivation the content of stable zinc, radioactive zinc and stable cadmium was determined in each component of the ecosystem. The results show the important influence of a conventional contaminant on the transfer of a radionuclide and justify the use of the term 'associate contaminant' to describe it. (author)

  7. Limiting values of radionuclide intake and air concentration and dose conversion factors for inhalation, submersion, and ingestion: Federal guidance report No. 11

    International Nuclear Information System (INIS)

    Eckerman, K.F.; Wolbarst, A.B.; Richardson, A.C.B.

    1988-09-01

    Radiation protection programs for workers are based, in the United States, on a hierarchy of limitations stemming from Federal guidance approved by the President. This guidance, which consists of principles, policies, and numerical primary guides, is used by Federal agencies as the basis for developing and implementing their own regulatory standards. The primary guides are usually expressed in terms of limiting doses to workers. The protection of workers against taking radioactive materials into the body, however, is accomplished largely through the use of regulations based on derived guides expressed in terms of quantities or concentrations of radionuclides. The values of these derived guides are chosen so as to assure that workers in work environments that conform to them are unlikely to receive radiation doses that exceed the primary guides. The purpose of the present report is to set forth derived guides that are consistent with current Federal radiation protection guidance. They are intended to serve as the basis for regulations setting upper bounds on the inhalation and ingestion of, and submersion in, radioactive materials in the workplace. The report also includes tables of exposure-to-dose conversion factors, for general use in assessing average individual committed doses in any population that is adequately characterized by Reference Man. 38 refs

  8. Limiting values of radionuclide intake and air concentration and dose conversion factors for inhalation, submersion, and ingestion: Federal guidance report No. 11

    Energy Technology Data Exchange (ETDEWEB)

    Eckerman, K.F.; Wolbarst, A.B.; Richardson, A.C.B.

    1988-09-01

    Radiation protection programs for workers are based, in the United States, on a hierarchy of limitations stemming from Federal guidance approved by the President. This guidance, which consists of principles, policies, and numerical primary guides, is used by Federal agencies as the basis for developing and implementing their own regulatory standards. The primary guides are usually expressed in terms of limiting doses to workers. The protection of workers against taking radioactive materials into the body, however, is accomplished largely through the use of regulations based on derived guides expressed in terms of quantities or concentrations of radionuclides. The values of these derived guides are chosen so as to assure that workers in work environments that conform to them are unlikely to receive radiation doses that exceed the primary guides. The purpose of the present report is to set forth derived guides that are consistent with current Federal radiation protection guidance. They are intended to serve as the basis for regulations setting upper bounds on the inhalation and ingestion of, and submersion in, radioactive materials in the workplace. The report also includes tables of exposure-to-dose conversion factors, for general use in assessing average individual committed doses in any population that is adequately characterized by Reference Man. 38 refs.

  9. Directionality Effects of Aligned Wind and Wave Loads on a Y-Shape Semi-Submersible Floating Wind Turbine under Rated Operational Conditions

    Directory of Open Access Journals (Sweden)

    Shengtao Zhou

    2017-12-01

    Full Text Available The Y-shape (triangular semi-submersible foundation has been adopted by most of the built full-scale floating wind turbines, such as Windfloat, Fukushima Mirai and Shimpuu. Considering the non-fully-symmetrical shape and met-ocean condition, the foundation laying angle relative to wind/wave directions will not only influence the downtime and power efficiency of the floating turbine, but also the strength and fatigue safety of the whole structure. However, the dynamic responses induced by various aligned wind and wave load directions have scarcely been investigated comparatively before. In our study, the directionality effects are investigated by means of combined wind and wave tests and coupled multi-body simulations. By comparing the measured data in three load directions, it is found that the differences of platform motions are mainly derived from the wave loads and larger pitch motion can always be observed in one of the directions. To make certain the mechanism underlying the observed phenomena, a coupled multi-body dynamic model of the floating wind turbine is established and validated. The numerical results demonstrate that the second-order hydrodynamic forces contribute greatly to the directionality distinctions for surge and pitch, and the first-order hydrodynamic forces determine the variations of tower base bending moments and nacelle accelerations. These findings indicate the directionality effects should be predetermined comprehensively before installation at sea, which is important for the operation and maintenance of the Y-shape floating wind turbines.

  10. Application of a UV-Vis submersible probe for capturing changes in DOC concentrations across a mire complex during the snowmelt and summer periods

    Science.gov (United States)

    Avagyan, Armine; Runkle, Benjamin; Kutzbach, Lars

    2013-04-01

    An accurate quantification of dissolved organic carbon (DOC) is crucial for understanding changes in water resources under the influence of climate, land use and urbanization. However, the conventionally used methods do not allow high frequency in situ analyses in remote or hostile environments (e.g., industrial wastewater or during environmental high-flow events, such as snowmelt or floods). In particular, missing measurements during the snowmelt period in landscapes of the boreal region can lead to significant miscalculations in regional carbon budgets. Therefore, the aim of the study was to test the performance of a portable, submersible UV-Vis spectrophotometer (spectro::lyser, s::can Messtechnik GmbH, Austria) during the snowmelt period in a boreal mire-forest catchment, and to provide a conceptual understanding of the spatial and temporal dynamics of DOC concentrations during and after snowmelt. During 2011, water samples were collected from the near-pristine Ust-Pojeg mire complex in northwestern Russia (61° 56'N, 50° 13'E). Sampling started during the spring snowmelt period and continued until late fall. The mire presented a mosaic of different landscape units. The mire consisted of minerogeous (fen), ombrogenous (bog), and transitional forest-mire (lagg) zones. Water samples were taken from the surface across the mire (22 points at 50-m intervals). DOC concentrations were analyzed directly at the study site using a portable, submersible UV-Vis spectrophotometer, which uses high-resolution absorbance measurements over the wavelength range 200-742.5 nm at 2.5-nm intervals as a proxy for DOC content. Because the DOC composition of fluids varies by site, a local calibration replaced the default settings of the spectro::lyser (Global Calibration) to enhance the accuracy of the measurements. To evaluate the local calibration and correct for drift, the same samples (n = 157) were additionally analyzed using the wet persulfate oxidation method (O

  11. Mid Ocean Ridge Processes at Very Low Melt Supply : Submersible Exploration of Smooth Ultramafic Seafloor at the Southwest Indian Ridge, 64 degree E

    Science.gov (United States)

    Cannat, M.; Agrinier, P.; Bickert, M.; Brunelli, D.; Hamelin, C.; Lecoeuvre, A.; Lie Onstad, S.; Maia, M.; Prampolini, M.; Rouméjon, S.; Vitale Brovarone, A.; Besançon, S.; Assaoui, E. M.

    2017-12-01

    Mid-ocean ridges are the Earth's most extensive and active volcanic chains. They are also, particularly at slow spreading rates, rift zones, where plate divergence is in part accommodated by faults. Large offset normal faults, also called detachments, are characteristic of slow-spreading ridges, where they account for the widespread emplacement of mantle-derived rocks at the seafloor. In most cases, these detachments occur together with ridge magmatism, with melt injection and faulting interacting to shape the newly formed oceanic lithosphere. Here, we seek to better understand these interactions and their effects on oceanic accretion by studying the end-member case of a ridge where magmatism is locally almost absent. The portion of the Southwest Indian ridge we are studying has an overal low melt supply, focused to discrete axial volcanoes, leaving almost zero melt to intervening sections of the axial valley. One of these nearly amagmatic section of the ridge, located at 64°E, has been the focus of several past cruises (sampling, mapping and seismic experiments). Here we report on the most recent cruise to the area (RV Pourquoi Pas? with ROV Victor; dec-jan 2017), during which we performed high resolution mapping, submersible exploration and sampling of the ultramafic seafloor and of sparse volcanic formations. Our findings are consistent with the flip-flop detachment hypothesis proposed for this area by Sauter et al. (Nature Geosciences, 2013; ultramafic seafloor forming in the footwall of successive detachment faults, each cutting into the footwall of the previous fault, with an opposite polarity). Our observations also document the extent and geometry of deformation in the footwall of a young axial detachment, the role of mass-wasting for the evolution of this detachment, and provide spectacular evidence for serpentinization-related hydrothermal circulation and for spatial links between faults and volcanic eruptions.

  12. Calibration Transfer Between a Bench Scanning and a Submersible Diode Array Spectrophotometer for In Situ Wastewater Quality Monitoring in Sewer Systems.

    Science.gov (United States)

    Brito, Rita S; Pinheiro, Helena M; Ferreira, Filipa; Matos, José S; Pinheiro, Alexandre; Lourenço, Nídia D

    2016-03-01

    Online monitoring programs based on spectroscopy have a high application potential for the detection of hazardous wastewater discharges in sewer systems. Wastewater hydraulics poses a challenge for in situ spectroscopy, especially when the system includes storm water connections leading to rapid changes in water depth, velocity, and in the water quality matrix. Thus, there is a need to optimize and fix the location of in situ instruments, limiting their availability for calibration. In this context, the development of calibration models on bench spectrophotometers to estimate wastewater quality parameters from spectra acquired with in situ instruments could be very useful. However, spectra contain information not only from the samples, but also from the spectrophotometer generally invalidating this approach. The use of calibration transfer methods is a promising solution to this problem. In this study, calibration models were developed using interval partial least squares (iPLS), for the estimation of total suspended solids (TSS) and chemical oxygen demand (COD) in sewage from Ultraviolet-visible spectra acquired in a bench scanning spectrophotometer. The feasibility of calibration transfer to a submersible, diode array equipment, to be subsequently operated in situ, was assessed using three procedures: slope and bias correction (SBC); single wavelength standardization (SWS) on mean spectra; and local centering (LC). The results showed that SBC was the most adequate for the available data, adding insignificant error to the base model estimates. Single wavelength standardization was a close second best, potentially more robust, and independent of the base iPLS model. Local centering was shown to be inadequate for the samples and instruments used. © The Author(s) 2016.

  13. The impact of an industrial effluent on the water quality, submersed macrophytes and benthic macroinvertebrates in a dammed river of Central Spain.

    Science.gov (United States)

    Gonzalo, Cristina; Camargo, Julio A

    2013-10-01

    This research was conducted in the middle Duratón River (Central Spain), in the vicinity of Burgomillodo Reservoir. An industrial effluent enters the river 300 m downstream from the dam. Fluoride and turbidity levels significantly increased downstream from the effluent, these levels being to some extent affected by differential water releases from the dam. The community of submersed macrophytes exhibited slighter responses and, accordingly, lower discriminatory power than the community of benthic macroinvertebrates, this indicating that metrics and indices based on macroinvertebrates may be more suitable for the biological monitoring of water pollution and habitat degradation in dammed rivers receiving industrial effluents. However, in relation to fluoride bioaccumulation at the organism level, macrophytes (Fontinalis antipyretica and Potamogeton pectinatus) were as suitable bioindicators of fluoride pollution as macroinvertebrates (Ancylus fluviatilis and Pacifastacus leniusculus). Fluoride bioaccumulation in both hard and soft tissues of these aquatic organisms could be used as suitable bioindicator of fluoride pollution (even lower than 1 mg F(-)L(-1)) in freshwater ecosystems. Echinogammarus calvus exhibited a great sensitivity to the toxicity of fluoride ions, with a 96 h LC₅₀ of 7.5 mg F(-)L(-1) and an estimated safe concentration of 0.56 mg F(-)L(-1). The great capacity of E. calvus to take up and retain fluoride during exposures to fluoride ions would be a major cause of its great sensitivity to fluoride toxicity. It is concluded that the observed fluoride pollution might be partly responsible for the absence of this native amphipod downstream from the industrial effluent. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Autonomous Optofluidic Chemical Analyzers for Marine Applications: Insights from the Submersible Autonomous Moored Instruments (SAMI for pH and pCO2

    Directory of Open Access Journals (Sweden)

    Chun-Ze Lai

    2018-01-01

    Full Text Available The commercial availability of inexpensive fiber optics and small volume pumps in the early 1990's provided the components necessary for the successful development of low power, low reagent consumption, autonomous optofluidic analyzers for marine applications. It was evident that to achieve calibration-free performance, reagent-based sensors would require frequent renewal of the reagent by pumping the reagent from an impermeable, inert reservoir to the sensing interface. Pumping also enabled measurement of a spectral blank further enhancing accuracy and stability. The first instrument that was developed based on this strategy, the Submersible Autonomous Moored Instrument for CO2 (SAMI-CO2, uses a pH indicator for measurement of the partial pressure of CO2 (pCO2. Because the pH indicator gives an optical response, the instrument requires an optofluidic design where the indicator is pumped into a gas permeable membrane and then to an optical cell for analysis. The pH indicator is periodically flushed from the optical cell by using a valve to switch from the pH indicator to a blank solution. Because of the small volume and low power light source, over 8,500 measurements can be obtained with a ~500 mL reagent bag and 8 alkaline D-cell battery pack. The primary drawback is that the design is more complex compared to the single-ended electrode or optode that is envisioned as the ideal sensor. The SAMI technology has subsequently been used for the successful development of autonomous pH and total alkalinity analyzers. In this manuscript, we will discuss the pros and cons of the SAMI pCO2 and pH optofluidic technology and highlight some past data sets and applications for studying the carbon cycle in aquatic ecosystems.

  15. Submersible UV-Vis spectroscopy for quantifying streamwater organic carbon dynamics: implementation and challenges before and after forest harvest in a headwater stream.

    Science.gov (United States)

    Jollymore, Ashlee; Johnson, Mark S; Hawthorne, Iain

    2012-01-01

    Organic material, including total and dissolved organic carbon (DOC), is ubiquitous within aquatic ecosystems, playing a variety of important and diverse biogeochemical and ecological roles. Determining how land-use changes affect DOC concentrations and bioavailability within aquatic ecosystems is an important means of evaluating the effects on ecological productivity and biogeochemical cycling. This paper presents a methodology case study looking at the deployment of a submersible UV-Vis absorbance spectrophotometer (UV-Vis spectro::lyzer model, s::can, Vienna, Austria) to determine stream organic carbon dynamics within a headwater catchment located near Campbell River (British Columbia, Canada). Field-based absorbance measurements of DOC were made before and after forest harvest, highlighting the advantages of high temporal resolution compared to traditional grab sampling and laboratory measurements. Details of remote deployment are described. High-frequency DOC data is explored by resampling the 30 min time series with a range of resampling time intervals (from daily to weekly time steps). DOC export was calculated for three months from the post-harvest data and resampled time series, showing that sampling frequency has a profound effect on total DOC export. DOC exports derived from weekly measurements were found to underestimate export by as much as 30% compared to DOC export calculated from high-frequency data. Additionally, the importance of the ability to remotely monitor the system through a recently deployed wireless connection is emphasized by examining causes of prior data losses, and how such losses may be prevented through the ability to react when environmental or power disturbances cause system interruption and data loss.

  16. Submersible UV-Vis Spectroscopy for Quantifying Streamwater Organic Carbon Dynamics: Implementation and Challenges before and after Forest Harvest in a Headwater Stream

    Directory of Open Access Journals (Sweden)

    Iain Hawthorne

    2012-03-01

    Full Text Available Organic material, including total and dissolved organic carbon (DOC, is ubiquitous within aquatic ecosystems, playing a variety of important and diverse biogeochemical and ecological roles. Determining how land-use changes affect DOC concentrations and bioavailability within aquatic ecosystems is an important means of evaluating the effects on ecological productivity and biogeochemical cycling. This paper presents a methodology case study looking at the deployment of a submersible UV-Vis absorbance spectrophotometer (UV-Vis spectro::lyzer model, s::can, Vienna, Austria to determine stream organic carbon dynamics within a headwater catchment located near Campbell River (British Columbia, Canada. Field-based absorbance measurements of DOC were made before and after forest harvest, highlighting the advantages of high temporal resolution compared to traditional grab sampling and laboratory measurements. Details of remote deployment are described. High-frequency DOC data is explored by resampling the 30 min time series with a range of resampling time intervals (from daily to weekly time steps. DOC export was calculated for three months from the post-harvest data and resampled time series, showing that sampling frequency has a profound effect on total DOC export. DOC exports derived from weekly measurements were found to underestimate export by as much as 30% compared to DOC export calculated from high-frequency data. Additionally, the importance of the ability to remotely monitor the system through a recently deployed wireless connection is emphasized by examining causes of prior data losses, and how such losses may be prevented through the ability to react when environmental or power disturbances cause system interruption and data loss.

  17. Sobrevivência de pupas de Lucilia eximia (Wiedemann (Diptera, Calliphoridae após submersão em laboratório Survival of Lucilia eximia (Wiedemann (Diptera, Calliphoridae pupae after submersion in laboratory

    Directory of Open Access Journals (Sweden)

    Alex Sandro Barros de Souza

    2009-01-01

    Full Text Available Entre Maio e Junho de 2008 foi observado a sobrevivência das pupas de Lucilia eximia (Diptera, Calliphoridae após submersão em laboratório. Para este experimento foram utilizadas 480 pupas de mesma idade, sendo estas divididas em oito grupos: o controle não foi submerso e os demais grupos foram submersos de um a sete dias. O aumento do período de submersão diminui a sobrevivência, com um dia de submersão a sobrevivência é de 80%, com dois dias 40%, é de 30% a partir do terceiro dia, no quarto dia cai para 23,34% e no quinto dia fica em 10%. Após este período a mortalidade sobe para 100%. Este padrão pode ser explicado pela curva "U-shaped" que ocorre no consumo de O2 durante o período pupal, onde o consumo é maior no início e no final do período pupal. O tempo de submersão também afeta o tempo de desenvolvimento, aumentando o período pupal. Estes dados têm o potencial para serem utilizados em investigações envolvendo Entomologia Forense, para a estimativa do tempo de submersão de um cadáver.Between May and June of 2008, the survival of the pupae of Lucilia eximia (Diptera, Calliphoridae was observed after submersion in laboratory. For this experiment 480 pupae of same age were used, these were divided in eight groups: the group control was not submerged and the other groups were submerged from one to seven days. The increase of the submersion period reduces the survival, with one day of submersion the survival is of 80%, with two days 40%, of 30% with three days, in the fourth day it falls to 23,34% and in the fifth day it is 10%. After this period the mortality rises to 100%. This pattern can be explained by the curve "U-shaped" that happens in the consumption of O2 during the pupal period, where the consumption is larger at the beginning and at the end of the pupal period. The time of submersion also affects the development time, increasing the pupal period. These data are potentially useful in estimating duration of

  18. Submersible canned motor transfer pump

    International Nuclear Information System (INIS)

    Guardiani, R.F.; Pollick, R.D.; Nyilas, C.P.; Denmeade, T.J.

    1997-01-01

    A transfer pump is described which is used in a waste tank for transferring high-level radioactive liquid waste from a waste tank and having a column assembly, a canned electric motor means, and an impeller assembly with an upper impeller and a lower impeller connected to a shaft of a rotor assembly. The column assembly locates a motor housing with the electric motor means adjacent to the impeller assembly which creates an hydraulic head, and which forces the liquid waste, into the motor housing to cool the electric motor means and to cool and/or lubricate the radial and thrust bearing assemblies. Hard-on-hard bearing surfaces of the bearing assemblies and a ring assembly between the upper impeller and electric motor means grind large particles in the liquid waste flow. Slots in the static bearing member of the radial bearing assemblies further grind down the solid waste particles so that only particles smaller than the clearances in the system can pass there through, thereby resisting damage to and the interruption of the operation of the transfer pump. The column assembly is modular so that sections can be easily assembled, disassembled and/or removed. A second embodiment employs a stator jacket which provides an alternate means for cooling the electric motor means and lubricating and/or cooling the bearing assemblies, and a third embodiment employs a variable level suction device which allows liquid waste to be drawn into the transfer pump from varying and discrete levels in the waste tank. 17 figs

  19. Submersible canned motor mixer pump

    International Nuclear Information System (INIS)

    Guardiani, R.F.; Pollick, R.D.

    1997-01-01

    A mixer pump is described used in a waste tank for mobilizing high-level radioactive liquid waste having a column assembly containing power cables, a motor housing with electric motor means which includes a stator can of a stator assembly and a rotor can of a rotor assembly, and an impeller assembly with an impeller connected to a shaft of the rotor assembly. The column assembly locates the motor housing with the electric motor means adjacent to the impeller which creates an hydraulic head, and which forces the liquid waste into the motor housing to cool the electric motor means and to lubricate radial and thrust bearing assemblies. Hard-on-hard bearing surfaces of the bearing assemblies and a ring assembly between the impeller and electric motor means act to grind down large particles in the liquid waste flow. These larger particles are received in slots in the static bearing members of the radial bearing assemblies. Only solid waste particles smaller than the clearances in the system can pass there through, thereby resisting damage to and the interruption of the operation of the mixer pump. 10 figs

  20. The Semi-Submersible Network

    Science.gov (United States)

    2012-12-01

    Hallan Sumergible de las FARC con sistemas por satélite e informáticos,” Semana, September 26, 2011, http://www.semana.com/nacion/hallan-sumergible-farc... sistemas -satelite-informaticos/164832- 3.aspx. 20 Rear Admiral Charles Michel, “Hearing on Border Security Threats to the Homeland: DHS’s Response to... web page on the FARC that provides a detailed description of the terror group’s history, sub-organizations, and their operational locations. In

  1. Eficácia do diquat no controle de Hydrilla verticillata, Egeria densa e Egeria najas e toxicidade aguda para o Guaru (Phallocerus caudimaculatus, em condições de laboratório Efficacy of diquat in the control of Hydrylla verticillata, Egeria densa and Egeria najas and its acute toxicity to Phallocerus caudimaculatus, under laboratory conditions

    Directory of Open Access Journals (Sweden)

    M.N.P. Henares

    2011-06-01

    Full Text Available No Brasil, as macrófitas aquáticas submersas, Egeria densa e Egeria najas, têm causado prejuízos aos usos múltiplos da água. Hydrilla verticillata foi recentemente introduzida, mas tem histórico como planta problemática nos EUA, no México e na Austrália. O objetivo deste trabalho foi avaliar as suscetibilidades relativas dessas três macrófitas aquáticas ao diquat e os riscos da utilização desse herbicida para o guaru (Phallocerus caudimaculatus. Para isso, foram instalados ensaios em condições de laboratório, a fim de avaliar a suscetibilidade relativa das três macrófitas por meio da manutenção de ponteiros dessas plantas em soluções contendo 0,0; 0,2; 0,4; 0,8; e 1,6 mg L-1 de diquat (Reward® por 14 dias. A avaliação foi realizada pela variação do acúmulo de matéria fresca e do comprimento dos ponteiros no período de exposição ao herbicida. H. verticillata mostrou maior sensibilidade ao diquat em comparação com as duas macrófitas do gênero Egeria, mesmo em baixas concentrações do herbicida. Nas maiores concentrações, E. densa mostrou maior sensibilidade que E. najas. O risco da aplicação do diquat para P. caudimaculatus foi estimado pela toxicidade aguda. Alevinos de P. caudimaculatus de 0,4 ± 0,2 mg foram expostos a soluções de 0,0; 1,0; 5,0; 10,0; 15,0; 20,0; 25,0; e 30,0 mg L-1 de diquat. A concentração letal de 50% (CL(I (50;96h do diquat estimada para P. caudimaculatus foi de 7,17 mg L-1. Para P. caudimaculatus, a toxicidade aguda foi superior à concentração recomendada para o controle de macrófitas aquáticas submersas, indicando risco muito baixo para esse peixe.In Brazil, the submerged plants Egeria densa and Egeria najas have caused damage to multiple uses of water. Hydrilla verticillata has been recently introduced, but it has a history as a problem plant in the U.S., Mexico and Australia. The objectives of this work were to assess the relative susceptibilities of these three

  2. Long-term Simulation Study about the Impact of submerse Macrophytes on thermal Stratification Dynamics and Transport Processes in an extreme shallow water lake - Lake Federsee

    Science.gov (United States)

    Wolf, Thomas; Pöschke, Franziska; Pflugbeil, Thomas

    2017-04-01

    temperature profiles shows that the lake nevertheless very shallow undergoes periods of distinct and stable thermal stratification which can last up to 10 days giving the right meteorological conditions (calm and warm). The overall vertical temperature gradients are in general stronger in "warm" years than in "cold" years. Furthermore we find most pronounced vertical temperature gradients during summer time whereas during months with smaller positive heat exchange temperature gradients are not as strong. Additionally the influence of the submerse macrophyte population on both - general circulation processes and the vertical mixing processes in the lake - are discussed. It is shown by numerical simulation studies that both - circulation pattern and mixing processes - are influenced severely by macrophytes in the lake slowing down the 3-dim flow field and decreasing vertical mixing processes leading to more and more pronounced stable stratified conditions in the lake.

  3. Surveys for Pathogens of Monoecious Hydrilla in 2013

    Science.gov (United States)

    2014-10-01

    were identified to genus and species when possible. Those that did not sporulate were placed in categories of moniliaceous (hyaline hyphae ) or...dematiaceous (dark hyphae ) Ascomycetes. Each isolate was also transferred to a one-half strength corn meal agar (Difco Inc., Detroit, Michigan) slant

  4. Eficiência de fluridone no controle de plantas aquáticas submersas no reservatório de Jupiá Fluridone efficacy for control of submersed aquatic weeds in the Jupiá reservoir

    Directory of Open Access Journals (Sweden)

    D.A.S. Marcondes

    2003-01-01

    Full Text Available O objetivo deste estudo foi avaliar a eficiência do herbicida fluridone no controle de plantas aquáticas submersas (Egeria densa, Egeria najas e Ceratophyllum demersum que ocorrem no reservatório da Usina Hidrelétrica Eng. Souza Dias (Jupiá, região noroeste do Estado de São Paulo. A pesquisa, que consistiu de aplicações de fluridone, foi conduzida em lagoas marginais do rio Tietê, denominadas Flórida e Barrenta. As lagoas foram divididas em faixas, cada uma delas representando um tratamento. As faixas das lagoas receberam uma aplicação inicial de fluridone, procurando-se atingir a concentração de 20 ppb. As aplicações subseqüentes foram dimensionadas para recompor e/ou manter esta concentração, sendo realizadas sempre com o auxílio de uma barra de aplicação munida de três mangueiras, com pontas injetoras submersas na água, em três profundidades (0,2, 0,6 e 1,2 m. O volume de aplicação foi mantido próximo a 54 l ha-1 de calda. Foram feitas avaliações visuais dos sintomas de fitointoxicação nas três espécies estudadas, assim como avaliação da biomassa. Nas condições da pesquisa, o fluridone controlou as macrófitas submersas Egeria najas e Egeria densa; quando cessou o efeito do fluridone, aconteceu a reinfestação de Egeria densa e Egeria najas; e não houve controle de Ceratophyllum demersum nem das espécies não-alvo, como Salvinia auriculata, Ipomoea spp., Merremia sp., Typha latifolia e Cyperus spp.The objective of this study was to evaluate the efficacy of the herbicide fluridone on the control of submersed aquatic weeds (Egeria densa Planch., Egeria najas Planch. and Ceratophyllum demersum, the major aquatic weeds in the reservoir of Engº Souza Dias (Jupiá Hydroelecric Power Plant, Itapura, São Paulo. The experiment, consisted of fluridone applications and was carried out in bays of the Tietê River, called Flórida and Barrenta. The lakes were divided into zones, each considered a treatment. All

  5. Long-term global response analysis of a vertical axis wind turbine supported on a semi-submersible floating platform: Comparison between operating and non-operating wind turbine load cases

    DEFF Research Database (Denmark)

    Collu, Maurizio; Manuel, Lance; Borg, Michael

    2015-01-01

    This study continues [1] the examination of the long-term global response of a floating vertical axis wind turbine (VAWT) situated off the Portuguese coast in the Atlantic Ocean. The VAWT, which consists of a 5-MW 3-bladed H-type rotor developed as part of the EU-FP7 H2OCEAN project, is assumed...... is adopted, as well as also taking into account the drag generated by the wind turbine tower. Short-term turbine load and platform motion statistics are established for individual sea states that are analysed. The long-term reliability yields estimates of 50-year loads and platform motions that takes...... to be mounted on the OC4 semi-submersible floating platform. Adding a non-operational load case (wind speed 35m/s), the sea states identified are used to carry out coupled dynamics simulations using the FloVAWT design tool, for which an improved wave elevation and relative force/moment time signals approach...

  6. Utilization of computational simulator for comparison of correlations in multiphase flow in ESP (Electrical Submersible Pumping) systems; Utilizacao de simulador computacional para a comparacao das correlacoes de escoamento multifasico em sistemas BCS

    Energy Technology Data Exchange (ETDEWEB)

    Anjos, Roselaine M. dos; Maitelli, Carla Wilza S.P.; Maitelli, Andre L. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Costa, Rutacio O. [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)

    2012-07-01

    Electrical Submersible Pumping (ESP) is an artificial lifting method which can be used both onshore and offshore for the production of high flow rates of liquid. By using the computational simulator for systems ESP developed by the AUTOPOC/LAUT - UFRN, this work aimed to evaluate empirical correlations for calculation of multiphase flow in tubing typical of artificial lifting systems operating by ESP. The parameters used for evaluating the correlations are some of the dynamic variables of the system such as head that indicates the lifting capacity of the system, the flow rate of fluid in the pump and the discharge pressure at the pump. Five (5) correlations were evaluated, from which only one considered slipping between phases, but does not take into account flow patterns and, four others considering slipping between the phases as well the flow patterns. The simulation results obtained for all these correlations were compared to results from a commercial computational simulator, extensively used in the oil industry. For both simulators, input values and simulation time, were virtually the same. The results showed that the simulator used in this work showed satisfactory performance, since no significant differences from those obtained with the commercial simulator. (author)

  7. Relationship of weed shiner and young-of-year bluegill and largemouth bass abundance to submersed aquatic vegetation in Navigation Pools 4, 8, and 13 of the Upper Mississippi River, 1998-2012

    Science.gov (United States)

    DeLain, Steven A.; Popp, Walter A.

    2014-01-01

    Aquatic vegetation provides food resources and shelter for many species of fish. This study found a significant relationship between increases in submersed aquatic vegetation (SAV) in four study reaches of the Upper Mississippi River (UMR) and increases in catch-per-unit-effort (CPUE) of weed shiners (Notropis texanus) and age-0 bluegills (Lepomis macrochirus) and largemouth bass (Micropterus salmoides) when all of the study reaches were treated collectively using Long Term Resource Monitoring Program (LTRMP) vegetation and fish data for 1998–2012. The selected fishes were more abundant in study reaches with higher SAV frequencies (Pool 8 and Lower Pool 4) and less abundant in reaches with lower SAV frequencies (Pool 13 and Upper Pool 4). When each study reach was examined independently, the relationship between SAV frequency and CPUE of the three species was not significant in most cases, the primary exception being weed shiners in Lower Pool 4. Results of this study indicate that the prevalence of SAV does affect relative abundance of these vegetation-associated fish species. However, the poor annual relationship between SAV frequency and age-0 relative abundance in individual study reaches indicates that several other factors also govern age-0 abundance. The data indicate that there may be a SAV frequency threshold in backwaters above which there is not a strong relationship with abundance of these fish species. This is indicated by the high annual CPUE variability of the three selected fishes in backwaters of Pool 8 and Lower Pool 4 when SAV exceeded certain frequencies.

  8. Eficiência de fluridone no controle de plantas aquáticas submersas e efeitos sobre algumas características ambientais Fluridone efficacy in controling submersed aquatic weeds and its effects on some environmental characteristics

    Directory of Open Access Journals (Sweden)

    D.A.S. Marcondes

    2002-01-01

    Full Text Available O objetivo deste estudo foi avaliar a eficiência do herbicida fluridone no controle de plantas aquáticas submersas (Egeria densa, Egeria najas e Ceratophyllum demersum, assim como seus efeitos sobre algumas características ambientais. A pesquisa foi conduzida no reservatório da Usina Hidrelétrica Eng. Souza Dias (Jupiá, região noroeste do Estado de São Paulo, em uma reentrância denominada lagoa Vírgula. A lagoa foi dividida em nove faixas e seis delas receberam uma aplicação inicial de fluridone para se obter uma concentração de 20 ppb. As aplicações subseqüentes foram dimensionadas para recompor esta concentração. Para o estudo do carreamento do herbicida pelo fluxo de água, foi efetuado o monitoramento das suas concentrações nas nove faixas da lagoa (com e sem aplicação e em áreas a jusante e a montante. Foram analisados os efeitos do fluridone sobre características ambientais como: turbidez, temperatura da água, condutividade elétrica, concentração de oxigênio, pH e resíduos de fluridone. A eficácia do controle foi avaliada visualmente (pelos sintomas de fitointoxicação nas três espécies estudadas e pela amostragem de biomassa. Observou-se que o fluridone controlou de forma satisfatória E. najas e E. densa. Quando cessou o efeito do fluridone, aconteceu a reinfestação de E. densa e E. najas. Não houve controle de C. demersum. O fluridone não produziu efeitos adversos sobre as características de qualidade ambiental estudadas.This study aimed to evaluate the efficacy of the herbicide fluridone to control submersed aquatic weeds (Egeria densa, Egeria najas and Ceratophyllum demersum, as well as its effects on some environmental characteristics. The research was carried out in the reservoir of Eng. Souza Dias (Jupiá Hydro-elecric plant power, Station in northwestern São Paulo, Brazil, in Lagoa Vírgula bay. The bay was divided in nine zones and six of them received an initial application of fluridone

  9. Optimization of Phenotyping Assays for the Model Monocot Setaria viridis.

    Science.gov (United States)

    Acharya, Biswa R; Roy Choudhury, Swarup; Estelle, Aiden B; Vijayakumar, Anitha; Zhu, Chuanmei; Hovis, Laryssa; Pandey, Sona

    2017-01-01

    Setaria viridis (green foxtail) is an important model plant for the study of C4 photosynthesis in panicoid grasses, and is fast emerging as a system of choice for the study of plant development, domestication, abiotic stress responses and evolution. Basic research findings in Setaria are expected to advance research not only in this species and its close relative S. italica (foxtail millet), but also in other panicoid grasses, many of which are important food or bioenergy crops. Here we report on the standardization of multiple growth and development assays for S. viridis under controlled conditions, and in response to several phytohormones and abiotic stresses. We optimized these assays at three different stages of the plant's life: seed germination and post-germination growth using agar plate-based assays, early seedling growth and development using germination pouch-based assays, and adult plant growth and development under environmentally controlled growth chambers and greenhouses. These assays will be useful for the community to perform large scale phenotyping analyses, mutant screens, comparative physiological analysis, and functional characterization of novel genes of Setaria or other related agricultural crops. Precise description of various growth conditions, effective treatment conditions and description of the resultant phenotypes will help expand the use of S. viridis as an effective model system.

  10. Optimization of Phenotyping Assays for the Model Monocot Setaria viridis

    Directory of Open Access Journals (Sweden)

    Biswa R. Acharya

    2017-12-01

    Full Text Available Setaria viridis (green foxtail is an important model plant for the study of C4 photosynthesis in panicoid grasses, and is fast emerging as a system of choice for the study of plant development, domestication, abiotic stress responses and evolution. Basic research findings in Setaria are expected to advance research not only in this species and its close relative S. italica (foxtail millet, but also in other panicoid grasses, many of which are important food or bioenergy crops. Here we report on the standardization of multiple growth and development assays for S. viridis under controlled conditions, and in response to several phytohormones and abiotic stresses. We optimized these assays at three different stages of the plant’s life: seed germination and post-germination growth using agar plate-based assays, early seedling growth and development using germination pouch-based assays, and adult plant growth and development under environmentally controlled growth chambers and greenhouses. These assays will be useful for the community to perform large scale phenotyping analyses, mutant screens, comparative physiological analysis, and functional characterization of novel genes of Setaria or other related agricultural crops. Precise description of various growth conditions, effective treatment conditions and description of the resultant phenotypes will help expand the use of S. viridis as an effective model system.

  11. Influência da imersão em água na resistência mecânica de misturas solo-grits compactadas e curadas com vistas a aplicações em estradas florestais Influence of water submersion on the mechanical strength of compacted and cured soil-grits mixtures for forest roads applications

    Directory of Open Access Journals (Sweden)

    Reginaldo Sérgio Pereira

    2007-01-01

    Full Text Available Avaliou-se o efeito da imersão em água dos corpos-de-prova sobre a resistência mecânica de misturas solo-grits. Trabalhou-se com dois solos da cidade de Viçosa, localizada na Zona da Mata Norte de Minas Gerais, Brasil, respectivamente de texturas predominantemente argilosa e arenosa e com o resíduo sólido industrial grits, um subproduto da indústria de celulose. Determinaram-se os parâmetros de resistência mecânica California Bearing Ratio (CBR e Resistência à Compressão Não-Confinada (RCNC de corpos-de-prova compactados nas energias de compactação referentes aos ensaios Proctor intermediário e Proctor modificado, com teores de grits na faixa de 4 a 28% e períodos de cura de 0, 7 e 28 dias. Com relação ao parâmetro CBR, os ensaios foram realizados segundo a metodologia tradicional (imersão em água dos corpos-de-prova por 96 horas e sem a imersão em água, visando determinar possíveis perdas na capacidade-suporte das misturas. No que tange ao parâmetro compressão não-confinada, os ensaios foram realizados em obediência à norma brasileira para misturas solo-cimento (imersão em água durante quatro horas antes da ruptura dos corpos-de-prova e sem a fase de imersão em água. Os resultados indicaram que a imersão em água dos corpos-de-prova influenciou significativamente a resistência mecânica das misturas solo-grits, que foram dependentes do tipo de ensaio empregado, tipo de solo, teor de grits, energia de compactação e período de cura.This paper address the influence of water submersion on mechanical strength parameters of soil-grits specimens. Two residual soils, predominantly clayey and sandy soils from the city of Viçosa, located in the State of Minas Gerais, "Zona da Mata Norte", Brazil, and waste from cellulose industry were used in the study. The laboratory testing program consisted of CBR (California Bearing Ratio and UCS (Unconfined Compression Strength of specimens prepared with waste contents

  12. Submersible Combatant Concept for Improved Littoral Warfare

    National Research Council Canada - National Science Library

    Leadmon, John

    2004-01-01

    .... power projection in many areas of the world. This problem is especially evident in the littoral environment, where enemy forces may employ a host of access denial methods including submarines, mines, small boats, and undersea sensor systems...

  13. Submersed Aquatic Vegetation Modeling Output Online

    National Research Council Canada - National Science Library

    Yin, Yao; Rogala, Jim; Sullivan, John; Rohweder, Jason

    2005-01-01

    .... Predictions for distribution of submerged aquatic vegetation beds can potentially increase hunter observance of voluntary avoidance zones where foraging birds are left alone to feed undisturbed...

  14. Aquatic Plant Control Research Program. Moneoecious hydrilla in the Potomac River.

    Science.gov (United States)

    1985-08-01

    K. Van USDA/ARS 3205 SW College Avenue Ft. Lauderdale, FL 33314 Dr. Howard E. Westerdahl * US Army Engineer Waterways Experiment Station ATTN: WESES-A...PO Box 631 Vicksburg, MS 39180-0631 * Dr. Westerdahl was primarily responsible for the development of this chapter and should be used as a point of...composition of the water system ( Westerdahl 1981). The literature is often contradictory in regard to these effects. Walker (1963) found increases in the

  15. Functionality of the plastron in adults of Neochetina eichhorniae Warner (Coleoptera, Curculionidae: aspects of the integument coating and submersion laboratory experiments Funcionalidade do plastrão em adultos de Neochetina eichhorniae Warner (Coleoptera, Curculionidae: aspectos do revestimento tegumentar e experimentos laboratoriais de submersão

    Directory of Open Access Journals (Sweden)

    Wesley Oliveira de Sousa

    2012-09-01

    Full Text Available The plastron theory was tested in adults of Neochetina eichhorniae Warner, 1970, through the analysis of the structure that coats these insects' integument and also through submersion laboratorial experiments. The tegument processes were recognized in three types: agglutinated scales with large perforations, plumose scales of varied sizes and shapes, and hairs. The experiments were carried out on 264 adult individuals which were kept submerged at different time intervals (n = 11 and in two types of treatment, natural non-aerated water and previously boiled water, with four repetitions for each treatment. The tests showed a maximum mortality after 24 hours of immersion in the previously boiled water treatment. The survival of the adults was negative and significantly correlated with the types of treatment employed and within the different time intervals. The values of oxygen dissolved in water (mg/l differed significantly within the types of treatment employed. They were positively correlated with the survival of the adults in the two types of treatment, although more markedly in the treatment with previously boiled water. The mortality of adults after 24 hours of submersion in the treatment with previously boiled water may be associated with the physical-chemical conditions of the non-tested water in this study, such as low surface tension and concentration of solutes. These results suggest plastron functionality in the adults of this species.A teoria plastrão foi testada em adultos de Neochetina eichhorniae Warner, 1970, por meio da análise da estrutura que reveste o tegumento destes insetos e em experimentos laboratoriais de submersão. Os processos tegumentares foram reconhecidos em três tipos: escamas aglutinadas e com perfurações largas; escamas plumosas de tamanhos e formas variadas; e pêlos. Os experimentos realizados com 264 indivíduos adultos os quais permaneciam submersos por diferentes intervalos de tempo (n = 11 e em dois

  16. Rice is the seed of the monocot plants Oryza sativa (Asian rice) or ...

    African Journals Online (AJOL)

    BIOTECH

    2013-10-16

    Oct 16, 2013 ... of culture. The regenerated plantlets were transferred to pots for acclimatization. About 80% of plants were survived in the greenhouse condition. Key words: Somatic embryogenesis, immature zygotic embryos, Indica rice, plant regeneration. INTRODUCTION. Rice (Oryza sativa L.) is one of the most ...

  17. Extra- and intracellular distribution of cytokinins in the leaves of monocots and dicots

    Czech Academy of Sciences Publication Activity Database

    Jiskrová, E.; Novák, Ondřej; Pospíšilová, H.; Holubová, K.; Karády, M.; Galuszka, P.; Robert, S.; Frébort, I.

    2016-01-01

    Roč. 33, č. 5 (2016), s. 735-742 ISSN 1871-6784 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : SOLID-PHASE EXTRACTION * MAIZE BETA-GLUCOSIDASE * ARABIDOPSIS-THALIANA Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.813, year: 2016

  18. A universe of dwarfs and giants: genome size and chromosome evolution in the monocot family Melanthiaceae.

    Science.gov (United States)

    Pellicer, Jaume; Kelly, Laura J; Leitch, Ilia J; Zomlefer, Wendy B; Fay, Michael F

    2014-03-01

    • Since the occurrence of giant genomes in angiosperms is restricted to just a few lineages, identifying where shifts towards genome obesity have occurred is essential for understanding the evolutionary mechanisms triggering this process. • Genome sizes were assessed using flow cytometry in 79 species and new chromosome numbers were obtained. Phylogenetically based statistical methods were applied to infer ancestral character reconstructions of chromosome numbers and nuclear DNA contents. • Melanthiaceae are the most diverse family in terms of genome size, with C-values ranging more than 230-fold. Our data confirmed that giant genomes are restricted to tribe Parideae, with most extant species in the family characterized by small genomes. Ancestral genome size reconstruction revealed that the most recent common ancestor (MRCA) for the family had a relatively small genome (1C = 5.37 pg). Chromosome losses and polyploidy are recovered as the main evolutionary mechanisms generating chromosome number change. • Genome evolution in Melanthiaceae has been characterized by a trend towards genome size reduction, with just one episode of dramatic DNA accumulation in Parideae. Such extreme contrasting profiles of genome size evolution illustrate the key role of transposable elements and chromosome rearrangements in driving the evolution of plant genomes. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  19. Cercosporoid fungi (Mycosphaerellaceae) 2. Species on monocots (Acoraceae to Xyridaceae, excluding Poaceae)

    OpenAIRE

    Braun, Uwe; Crous, Pedro W.; Nakashima, Chiharu

    2014-01-01

    Cercosporoid fungi (formerly Cercospora s. lat.) represent one of the largest groups of hyphomycetes belonging to the Mycosphaerellaceae (Ascomycota). They include asexual morphs, asexual holomorphs, or species with mycosphaerella-like sexual morphs. Most of them are leaf-spotting plant pathogens with special phytopathological relevance. In the first part of a new monographic work, cercosporoid hyphomycetes occurring on other fungi (fungicolous species), on ferns (pteridophytes) and gymnosper...

  20. Characterizing the effects of brassinosteroids on root development in monocot plant species

    DEFF Research Database (Denmark)

    de Bang, Louise

    . With TILLING, two mutants of selected BR-related genes were identified in a Brachypodium distachyon mutant population. However, compared to the wild type, the mutants did not produce more biomass. The work with BR effects on plant root growth stimulated an interest for roots and root development, which...

  1. Analysis of ABCB phosphoglycoproteins (PGPs) and their contribution to monocot biomass, structural stability, and productivity

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, Angus Stuart [Purdue University

    2014-09-23

    Efforts to manipulate production of plant secondary cell walls to improve the quality of biofuel feedstocks are currently limited by an inability to regulate the transport of small molecule components out of the cell. Plant ABCB p-glycoproteins are a small family of plasma membrane organic molecule transporters that have become primary targets for this effort, as they can potentially be harnessed to control the export of aromatic compounds and organic acids. However, unlike promiscuous mammalian ABCBs that function in multidrug resistance, all plant ABCB proteins characterized to date exhibit relatively narrow substrate specificity. Although ABCBs exhibit a highly conserved architecture, efforts to modify ABCB activity have been hampered by a lack of structural information largely because an eukaryotic ABCB protein crystal structure has yet to be obtained. Structure/ function analyses have been further impeded by the lack of a common heterologous expression system that can be used to characterize recombinant ABCB proteins, as many cannot be functionally expressed in S. cereviseae or other systems where proteins with analogous function can be readily knocked out. Using experimentally-determined plant ABCB substrate affinities and the crystal structure of the bacterial Sav1866 “half” ABC transporter, we have developed sequence/structure models for ABCBs that provide a testable context for mutational analysis of plant ABCB transporters. We have also developed a flexible heterologous expression system in Schizosaccharomyces pombe in which all endogenous ABC transporters have been knocked out. The effectiveness of this system for transport studies has been demonstrated by the successful functional expression all of the known PIN, AUX/LAX and ABCB auxin transporters. Our central hypothesis is that the domains of the ABCB proteins that we have identified as substrate docking sites and regulators of transport directionality can be altered or swapped to alter the transport characteristics of the proteins. We propose to combine computer modelling, mutational analyses, and complementation of well characterized Arabidopsis abcb4,14,and 19 mutants to elucidate ABCB function. The long term objective of this project is to enhance ABCB transport of cell wall components, to manipulate the direction of ABCB substrate transport, and, ultimately, to produce “designer” ABC transporters that can be used to modify plant feedstock quality.

  2. Effects of cold stratification, sulphuric acid, submersion in hot and ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-06

    Jul 6, 2009 ... deciduous shrubs and small trees with a distribution rang- ing from the Mediterranean region and South-Eastern. *Corresponding author. ..... Handbook 450, USDA Forest Service, Washington DC, USA. Ürgenç S, Çepel N ...

  3. Apparatus for deploying and energizing submersible electric motor downhole

    International Nuclear Information System (INIS)

    Conner, S.E.; Dwiggins, J.L.; Brookbank, E.B.

    1991-01-01

    This patent describes an apparatus for deploying and energizing a submergible electric motor downhole. It comprises a cable socket assembly and a cable connecting-and-sealing chamber assembly adapted to be arranged seriatim in the path of cable means and the motor, the assemblies having first and second housings, respectively, means for connecting a lower end of the first housing to an upper end of the second housing, a lower end of the second housing being adapted for connection to the motor, the cable socket assembly having an attachment portion including means for attaching a weight-bearing cable of the cable means to the first housing via a breakaway connection, the first housing having a passage therein adapted to pass an electrical cable of the cable means to the second housing, the second housing being divided by a body therein into first and second chambers sealed from each other, the first chamber being adapted to communicate sealingly with the passage and the second chamber being adapted to communicate sealingly with the interior of the motor, a first set of electrical conductors in the first chamber and a second set of electrical conductors in the second chamber, the body having feed-through means for electrically interconnecting conductors of the first set with corresponding conductors of the second set, the conductors of the first set having electrical connector parts adapted to connect releasably with corresponding electrical connector parts of the electrical cable, and the conductors of the second set having electrical connector parts adapted to connect with corresponding electrical connector parts of the motor, each of the chambers being adapted to be filled with fluid to exclude well fluid therefrom

  4. North Carolina Seagrass Submersed Rooted Vasculars 1990 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A GIS data set of polygon data interpreted from aerial photography taken by NOAA/NOS Photogrammetry Branch depicting areas of Aquatic Beds of Rooted Vascular Plants...

  5. North Carolina Seagrass Submersed Rooted Vasculars 1990 Biotic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A GIS data set of polygon data interpreted from aerial photography taken by NOAA/NOS Photogrammetry Branch depicting areas of Aquatic Beds of Rooted Vascular Plants...

  6. North Carolina Seagrass Submersed Rooted Vasculars 1990 Substrate

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A GIS data set of polygon data interpreted from aerial photography taken by NOAA/NOS Photogrammetry Branch depicting areas of Aquatic Beds of Rooted Vascular Plants...

  7. Development of a submersible gravimeter on underwater vehicles

    Science.gov (United States)

    Yamada, T.; Kanazawa, T.; Fujimoto, H.; Shinohara, M.; Ishihara, T.; Araya, A.; Iizasa, K.; Tsukioka, S.

    2012-12-01

    Gravity is one of the powerful indices to profile underground structures. Surface ship gravimeters are popular tool for the purpose of collecting gravity values in marine region. They enable you to obtain gravity values from large area easily, while the resolutions are relatively low because of the distance between the sea surface and bottom. Otherwise, ocean bottom gravimeters are able to be observed gravity with high resolution, but they have still covered few limited sites so that they are designed to do observation in quiet only. In some cases, such as hydrothermal deposit survey, the medium performance both in resolution and size of survey area are required. This paper describes a gravimeter we have been developing for satisfying the requirements. Our target is to detect gravity anomalies less than 1 mgal by using an underwater vehicle. This setting is roughly equivalent to find a typical hydrothermal deposit with a dimension of 0.5 km x 0.5 km x 10 m and a density contrast of 1 g/cm3 when we set the sensor at 50 m high from the seafloor. There are some issues such as noise reduction, robustness and downsizing to clear the target. A gravity sensor (Micro-g LaCoste S-174) is mounted on a gimbal control unit with an inertial navigation sensor for the problems. These are stored in a sphere vessel made of titanium alloy (125 kgf in air, 32 kgf in water) and it is available in 3500 m below sea surface. Furthermore, in order to reduce high frequency noise due to mainly the vehicle motion through a low-pass filter, data are able to be stored at sampling rates of approximately 100 Hz. The logging system and control unit for communication to/from ship is stored another canister (22 kgf in air, 10 kgf in water). We made gravity measurement experiments to examine the effectiveness of the gimbal system and filtering application. The gravimeter was set on a machine simulating pitch and roll motions with a period of 16 s and an amplitude of 7.5 degrees, which is greater than expected in actual vehicle motions. We applied two-step low-pass filtering with 1 s and 150 s Gaussian filters to the collected data. The filtering widths correspond to a spatial resolution of 0.1 km order after applied if the vehicle speed be 2 knots. The RMS errors of pitch and roll motions are 0.04 mgal and 0.02 mgal, respectively, after processing of the filtering, tilt and earth tide corrections and removal of linear temporal drift. This is satisfied with our requirement to detect gravity anomalies enough. We are now ready to step into in situ experiments. The first cruise is planning in September 2012 to evaluate this gravimeter and another instrument, gravity gradiometer jointly by using an autonomous underwater vehicle, URASHIMA. In this presentation, we will show you the target of this research, details of the instrument and performance, and the overview and preliminary results of the first cruise.

  8. Effects of eutrophication and temperature on submersed rooted plants

    DEFF Research Database (Denmark)

    Raun, Ane-Marie Løvendahl

    nutrient levels facilitate the formation of pelagic alga blooms which lead to poor light conditions (Nielsen et al., 2002). However, the lack of re‐colonization after reduced nutrient loading for Zostera marina and other seagrasses indicates that other factors influence the pattern. Sedimentation...... in combination with high temperature affect internal oxygen concentrations, growth and survival of aquatic macrophytes. Measurements of internal oxygen levels were made on several north temperate and tropical marine seagrass species exposed to a range of water column oxygen concentrations. The combined effects...... of eutrophication and temperatures were clarified for the temporal seagrass Zostera marina. Furthermore, the direct effect of sediment enrichment with labile organic matter was examined for four freshwater species with different growth strategies (isoetids: Lobelia dortmanna and Littorella uniflora, and elodeids...

  9. Surveys for Biological Control Agents of Hydrilla verticillata in the People’s Republic of China in 2013

    Science.gov (United States)

    2017-03-01

    Cullen , D. T. Briese, D. J. Kriticos, W. M. Lonsdale, L. Morin, and J. K. Scott, 529-538. Canberra, Australia: CSIRO. ERDC/EL TR-17-3 15 Grodowitz M...J. Aquat. Plant Manage. 46:42-50 Manrique, V., J. P. Cuda, W. A. Overholt, D. Williams , G. Wheeler, G. 2008. Effect of host-plant genotypes on the...Review of the Literature. www.northeastans.org/docs/hydrillalitsearch12.31.12.pdf. Accessed14 April 2014. Overholt, W. A., R. Copeland, D. Williams

  10. Tomato Cf resistance proteins mediate recognition of cognate homologous effectors from fungi pathogenic on dicots and monocots.

    Science.gov (United States)

    Stergiopoulos, Ioannis; van den Burg, Harrold A; Okmen, Bilal; Beenen, Henriek G; van Liere, Sabine; Kema, Gert H J; de Wit, Pierre J G M

    2010-04-20

    Most fungal effectors characterized so far are species-specific and facilitate virulence on a particular host plant. During infection of its host tomato, Cladosporium fulvum secretes effectors that function as virulence factors in the absence of cognate Cf resistance proteins and induce effector-triggered immunity in their presence. Here we show that homologs of the C. fulvum Avr4 and Ecp2 effectors are present in other pathogenic fungi of the Dothideomycete class, including Mycosphaerella fijiensis, the causal agent of black Sigatoka disease of banana. We demonstrate that the Avr4 homolog of M. fijiensis is a functional ortholog of C. fulvum Avr4 that protects fungal cell walls against hydrolysis by plant chitinases through binding to chitin and, despite the low overall sequence homology, triggers a Cf-4-mediated hypersensitive response (HR) in tomato. Furthermore, three homologs of C. fulvum Ecp2 are found in M. fijiensis, one of which induces different levels of necrosis or HR in tomato lines that lack or contain a putative cognate Cf-Ecp2 protein, respectively. In contrast to Avr4, which acts as a defensive virulence factor, M. fijiensis Ecp2 likely promotes virulence by interacting with a putative host target causing host cell necrosis, whereas Cf-Ecp2 could possibly guard the virulence target of Ecp2 and trigger a Cf-Ecp2-mediated HR. Overall our data suggest that Avr4 and Ecp2 represent core effectors that are collectively recognized by single cognate Cf-proteins. Transfer of these Cf genes to plant species that are attacked by fungi containing these cognate core effectors provides unique ways for breeding disease-resistant crops.

  11. Tomato Cf resistance proteins mediate recognition of cognate homologous effectors from fungi pathogenic on diots and monocots

    NARCIS (Netherlands)

    Stergiopoulos, I.; Burg, van den H.A.; Ökmen, B.; Beenen, H.G.; Liere, van S.; Kema, G.H.J.; Wit, de P.J.G.M.

    2010-01-01

    Most fungal effectors characterized so far are species-specific and facilitate virulence on a particular host plant. During infection of its host tomato, Cladosporium fulvum secretes effectors that function as virulence factors in the absence of cognate Cf resistance proteins and induce

  12. Diel time-courses of leaf growth in monocot and dicot species: endogenous rhythms and temperature effects.

    Science.gov (United States)

    Poiré, Richard; Wiese-Klinkenberg, Anika; Parent, Boris; Mielewczik, Michael; Schurr, Ulrich; Tardieu, François; Walter, Achim

    2010-06-01

    Diel (24 h) leaf growth patterns were differently affected by temperature variations and the circadian clock in several plant species. In the monocotyledon Zea mays, leaf elongation rate closely followed changes in temperature. In the dicotyledons Nicotiana tabacum, Ricinus communis, and Flaveria bidentis, the effect of temperature regimes was less obvious and leaf growth exhibited a clear circadian oscillation. These differences were related neither to primary metabolism nor to altered carbohydrate availability for growth. The effect of endogenous rhythms on leaf growth was analysed under continuous light in Arabidopsis thaliana, Ricinus communis, Zea mays, and Oryza sativa. No rhythmic growth was observed under continuous light in the two monocotyledons, while growth rhythmicity persisted in the two dicotyledons. Based on model simulations it is concluded that diel leaf growth patterns in mono- and dicotyledons result from the additive effects of both circadian-clock-controlled processes and responses to environmental changes such as temperature and evaporative demand. Apparently very distinct diel leaf growth behaviour of monocotyledons and dicotyledons can thus be explained by the different degrees to which diel temperature variations affect leaf growth in the two groups of species which, in turn, depends on the extent of the leaf growth control by internal clocks.

  13. A Virus-Induced Assay for Functional Dissection and Analysis of Monocot and Dicot Flowering Time Genes.

    Science.gov (United States)

    Qin, Cheng; Chen, Weiwei; Shen, Jiajia; Cheng, Linming; Akande, Femi; Zhang, Ke; Yuan, Chen; Li, Chunyang; Zhang, Pengcheng; Shi, Nongnong; Cheng, Qi; Liu, Yule; Jackson, Stephen; Hong, Yiguo

    2017-06-01

    Virus-induced flowering (VIF) uses virus vectors to express Flowering Locus T ( FT ) to induce flowering in plants. This approach has recently attracted wide interest for its practical applications in accelerating breeding in crops and woody fruit trees. However, the insight into VIF and its potential as a powerful tool for dissecting florigenic proteins remained to be elucidated. Here, we describe the mechanism and further applications of Potato virus X (PVX)-based VIF in the short-day Nicotiana tabacum cultivar Maryland Mammoth. Ectopic delivery of Arabidopsis ( Arabidopsis thaliana ) AtFT by PVX/AtFT did not induce the expression of the endogenous FT ortholog NtFT4 ; however, it was sufficient to trigger flowering in Maryland Mammoth plants grown under noninductive long-day conditions. Infected tobacco plants developed no systemic symptoms, and the PVX-based VIF did not cause transgenerational flowering. We showed that the PVX-based VIF is a much more rapid method to examine the impacts of single amino acid mutations on AtFT for floral induction than making individual transgenic Arabidopsis lines for each mutation. We also used the PVX-based VIF to demonstrate that adding a His- or FLAG-tag to the N or C terminus of AtFT could affect its florigenic activity and that this system can be applied to assay the function of FT genes from heterologous species, including tomato ( Solanum lycopersicum ) SFT and rice ( Oryza sativa ) Hd3a Thus, the PVX-based VIF represents a simple and efficient system to identify individual amino acids that are essential for FT-mediated floral induction and to test the ability of mono- and dicotyledonous FT genes and FT fusion proteins to induce flowering. © 2017 American Society of Plant Biologists. All Rights Reserved.

  14. The monitoring, operation and assessment of a semi-submersible tidal stream prototype

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    It is feasible that for deep water (60-80m) sites around the British Isles, the most suitable tidal stream turbine is the free-swinging type. As a forerunner of a commercial system, a small-scale turbine (1.5m diameter) was studied firstly in a swimming pool and secondly in the River Thames. The river tests were carried out over 15 months on both flood and ebb tides. The results of the tests and conclusions drawn are reported. The tests demonstrated the promise of the system but a number of problems arose which will need to be resolved before designing a commercial-scale system. The problems mainly concerned the method of handling the large torque and thrust loads, and buoyancy in strong tides.

  15. Chemical Fouling Reduction of a Submersible Steel Spectrophotometer in Estuarine Environments Using a Sacrificial Zinc Anode.

    Science.gov (United States)

    Tait, Zachary S; Thompson, Megan; Stubbins, Aron

    2015-07-01

    The availability of in situ spectrophotometers, such as the S::CAN spectro::lyser, has expanded the possibilities for high-frequency water quality data collection. However, biological and chemical fouling can degrade the performance of in situ spectrophotometers, especially in saline environments with rapid flow rates. A complex freshwater washing system has been previously designed to reduce chemical fouling for the S::CAN spectro::lyser spectrophotometer. In the current study, we present a simpler, cheaper alternative: the attachment of a sacrificial zinc anode. Results are presented detailing the S::CAN spectro::lyser performance with and without the addition of the sacrificial anode. Attachment of the zinc anode provided efficient corrosion protection during 2-wk deployments in a highly dynamic (average tidal range, 2.5 m) saline tidal saltmarsh creek at Groves Creek, Skidaway Institute of Oceanography, Savannah, GA. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  16. Structural Dynamic Analysis of Semi-Submersible Floating Vertical Axis Wind Turbines

    Directory of Open Access Journals (Sweden)

    Jeremiah Ishie

    2016-12-01

    Full Text Available The strong and stable wind at offshore locations and the increasing demand for energy have made the application of wind turbines in deeper water surge. A novel concept of a 5 MW baseline Floating Vertical Axis Wind Turbine (FVAWT and a 5 MW optimised FVAWT with the DeepWind Darrieus rotor and the optimised DeepWind Darrieus rotor, respectively, were studied extensively. The structural responses, fatigue damages, platform global motions and mooring line dynamics of the FVAWTs were investigated comprehensively during normal operating conditions under steady wind and turbulent wind conditions, using a coupled non-linear aero-hydro-servo-elastic code (the Simo-Riflex-DMS code which was developed by Wang et al. for modeling FVAWTs. This coupled code incorporates the models for the turbulent wind field, aerodynamics, hydrodynamics, structural dynamics, and generator controller. The simulation is performed in a fully coupled manner in time domain. The comparison of responses under different wind conditions were used to demonstrate the effect of turbulence on both FVAWTs dynamic responses. The turbulent wind condition has the advantage of reducing the 2P effects. Furthermore, comparative studies of the FVAWTs responses were undertaken to explore the advantages of adopting the optimised 5 MW DeepWind Darrieus rotor over the baseline model. The results identified the 5 MW optimised FVAWT to having: lower Fore-Aft (FA but higher lower Side-Side (SS bending moments of structural components; lower motions amplitude; lower short-term fatigue equivalent loads and a further reduced 2P effects.

  17. Submersible Data (Dive Trackpoints) for Lophelia II 2008 - Office of Ocean Exploration and Research

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the Remotely Operated Vehicle SeaEye Falcon along its track during four dives of the "Lophelia II 2008" expedition sponsored by the...

  18. Submersible Data (Dive Trackpoints) for Expedition to the Deep Slope 2007 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the ROV Jason along its track during sixteen dives of the 2007 "Expedition to the Deep Slope" expedition sponsored by the National...

  19. Self-stacked submersible microbial fuel cell (SSMFC) for improved remote power generation from lake sediments

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2012-01-01

    external resistance (≤400 Ω in this study) was applied. In addition, the internal resistance and OCV were the most important parameters for predicting which cell unit had the highest probability to undergo voltage reversal. Use of a capacitor was found to be an effective way to prevent voltage reversal......Electric energy can be harvested from aquatic sediments by utilizing microbialfuelcells (MFCs). A main challenge of this application is the limited voltage output. In this study, an innovative self-stackedsubmersible MFC (SSMFC) was developed to improve the voltage generation from lakesediments....... The SSMFC successfully produced a maximum power density of 294 mW/m2 and had an open circuit voltage (OCV) of 1.12 V. However, voltage reversal was observed in one cell at high current density. Investigation on the cause for voltage reversal revealed that voltage reversal was occurring only when low...

  20. Remediation of a uranium-contaminated quarry utilizing submersible, remotely operated vehicles

    International Nuclear Information System (INIS)

    Fleming, K.N.

    1992-01-01

    The Kerr Hollow Quarry (KHQ) Disposal Site on the Oak Ridge (Tennessee) Reservation was previously used to treat and dispose of pyrophoric and water-reactive wastes contaminated with small quantities of radioactive materials (almost exclusively uranium and uranium daughters) from processes at the Department of Energy-owned, Oak Ridge Y-12 Plant and Oak Ridge National Laboratory. This paper describes remediation techniques utilizing a small, remotely operated submarine with an attached camera to visually locate waste containers, determine whether containers have been breached, transport small containers, and direct a larger remotely operated grappling machine to move larger waste for shredding operations. Most of the solid waste is reduced under water by a metal shredder. Non-shreddable items (e. g. , gas cylinders and larger structures) are mechanically breached under water to allow the contents to fully react. The waste is then removed from the water, monitored, the material is segregated, and transported to a temporary waste storage area until disposal

  1. Development of an Underwater Manipulator for Use on a Free-Swimming Unmanned Submersible.

    Science.gov (United States)

    1980-10-01

    Compatibility between the O-ring and the fluids with which it will be used is another major design problem. Nitrile or Buna N ( NBR ) is today the most widely...used elastomer in the seal industry. In fact, most military rubber specifications for oil-resistant O-rings require nitrile-base compounds. Because of...their fair chemical resistance and their poor resistance against ozone, which might be generated by brush arc-ing, O-rings made of fluorocarbon rubber

  2. Small Submersible Robust Microflow Cytometer for Quantitative Detection of Phytoplankton, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Translume will develop an extremely robust, inexpensive micro flow cytometer (mFCM) for quantitative detection of phytoplankton. This device will be designed to be...

  3. A Submersed Macrophyte Index of Condition for the Upper Mississippi River

    Science.gov (United States)

    Portions of the Upper Mississippi River are listed as impaired for aquatic life use under section 303(d) of the United States Clean Water Act by the State of Minnesota’s Pollution Control Agency and Wisconsin’s Department of Natural Resources for exceeding turbidity and eutrophic...

  4. Shear Stress and Sediment Resuspension in Canopy-and Meadow-Forming Submersed Macrophyte Communities

    National Research Council Canada - National Science Library

    James, William

    2001-01-01

    .... Studies were conducted at Lake Christina, Minnesota, in late August-early September 1998, when macrophyte biomass levels exceeded 200 g/m2 and in June 2000, when biomass was greatly reduced (<20 g/m2...

  5. Organ and effective dose rate coefficients for submersion exposure in occupational settings

    International Nuclear Information System (INIS)

    Veinot, K.G.; Dewji, S.A.; Hiller, M.M.; Eckerman, K.F.; Easterly, C.E.

    2017-01-01

    External dose coefficients for environmental exposure scenarios are often computed using assumption on infinite or semi-infinite radiation sources. For example, in the case of a person standing on contaminated ground, the source is assumed to be distributed at a given depth (or between various depths) and extending outwards to an essentially infinite distance. In the case of exposure to contaminated air, the person is modeled as standing within a cloud of infinite, or semi-infinite, source distribution. However, these scenarios do not mimic common workplace environments where scatter off walls and ceilings may significantly alter the energy spectrum and dose coefficients. In this paper, dose rate coefficients were calculated using the International Commission on Radiological Protection (ICRP) reference voxel phantoms positioned in rooms of three sizes representing an office, laboratory, and warehouse. For each room size calculations using the reference phantoms were performed for photons, electrons, and positrons as the source particles to derive mono-energetic dose rate coefficients. Since the voxel phantoms lack the resolution to perform dose calculations at the sensitive depth for the skin, a mathematical phantom was developed and calculations were performed in each room size with the three source particle types. Coefficients for the noble gas radionuclides of ICRP Publication 107 (e.g., Ne, Ar, Kr, Xe, and Rn) were generated by folding the corresponding photon, electron, and positron emissions over the mono-energetic dose rate coefficients. Results indicate that the smaller room sizes have a significant impact on the dose rate per unit air concentration compared to the semi-infinite cloud case. For example, for Kr-85 the warehouse dose rate coefficient is 7% higher than the office dose rate coefficient while it is 71% higher for Xe-133. (orig.)

  6. Experimental Applications of the Modular Acoustic System for the Submersible ALVIN

    Science.gov (United States)

    1975-08-01

    frequency and DD F ORM 1473 E DIT ION OF i NOV ISS IS OB SOL ET E 4-nlssfe SE CU FITY C L ASSI FIC AT ION O F T HI S P AG E tIIIen 01)1a3 I ~rI •i...conduc4ted on ALVIN during that period have be-n summarized in the Woods Hole Oceano -I graphic Institutic.i technical report WHOI-74-60 (1974). ONR sup...Agency of the Department of Defense by the Woods Hole Oceano - graphic Institution, Woods Hole, Mass., Sept. 30, 1972. Dr. Robert W. Morse, Principal

  7. 76 FR 80291 - Revisions to the Export Administration Regulations (EAR): Control of Submersible Vessels...

    Science.gov (United States)

    2011-12-23

    ... rule and to avoid, to the extent possible, situations where transactions would require licenses from... align the CCL with the WAML and the Missile Technology Control Regime Equipment, Software and Technology..., which currently impose a license requirement for five countries. A license also would be required, in...

  8. Transitioning Submersible Chemical Analyzer Technologies for Sustained, Autonomous Observations from Profiling Moorings, Gliders and other AUVs

    National Research Council Canada - National Science Library

    Hanson, Alfred K; Donaghay, Percy L; Moore, Casey; Arrieta, Richard

    2005-01-01

    The long term goal is to transition existing prototype autonomous profiling nutrient analyzers into commercial products that can be readily deployed on autonomous profiling moorings, coastal gliders...

  9. First-Language Skills of Bilingual Turkish Immigrant Children Growing up in a Dutch Submersion Context

    Science.gov (United States)

    Akoglu, Gözde; Yagmur, Kutlay

    2016-01-01

    The interdependence between the first and second language of bilingual immigrant children has not received sufficient attention in research. Most studies concentrate on mainstream language skills of immigrant pupils. In some studies, the gaps in the language development of immigrant children are documented by comparing mainstream pupils with…

  10. First-language skills of bilingual Turkish immigrant children growing up in a Dutch submersion context

    NARCIS (Netherlands)

    Akoglu, Gözde; Yagmur, Kutlay

    2016-01-01

    The interdependence between the first and second language of bilingual immigrant children has not received sufficient attention in research. Most studies concentrate on mainstream language skills of immigrant pupils. In some studies, the gaps in the language development of immigrant children are

  11. 77 FR 2957 - Application for Manufacturing Authority, Liberty Pumps, Inc. (Submersible and Water Pumps...

    Science.gov (United States)

    2012-01-20

    ... formally filed on January 12, 2012. The Liberty Pumps, Inc., facility (108 employees, 9.1 acres, production... from abroad (representing 30 to 40% of the value of the finished pumps) include: Plastic (polyamide) resins, plastic boxes/cases/tanks, articles of plastic, rubber gaskets/seals, labels, wood pallets...

  12. Organ and effective dose rate coefficients for submersion exposure in occupational settings

    Energy Technology Data Exchange (ETDEWEB)

    Veinot, K.G. [Easterly Scientific, Knoxville, TN (United States); Y-12 National Security Complex, Oak Ridge, TN (United States); Dewji, S.A.; Hiller, M.M. [Center for Radiation Protection Knowledge, Oak Ridge National Laboratory, Oak Ridge, TN (United States); Eckerman, K.F.; Easterly, C.E. [Easterly Scientific, Knoxville, TN (United States)

    2017-11-15

    External dose coefficients for environmental exposure scenarios are often computed using assumption on infinite or semi-infinite radiation sources. For example, in the case of a person standing on contaminated ground, the source is assumed to be distributed at a given depth (or between various depths) and extending outwards to an essentially infinite distance. In the case of exposure to contaminated air, the person is modeled as standing within a cloud of infinite, or semi-infinite, source distribution. However, these scenarios do not mimic common workplace environments where scatter off walls and ceilings may significantly alter the energy spectrum and dose coefficients. In this paper, dose rate coefficients were calculated using the International Commission on Radiological Protection (ICRP) reference voxel phantoms positioned in rooms of three sizes representing an office, laboratory, and warehouse. For each room size calculations using the reference phantoms were performed for photons, electrons, and positrons as the source particles to derive mono-energetic dose rate coefficients. Since the voxel phantoms lack the resolution to perform dose calculations at the sensitive depth for the skin, a mathematical phantom was developed and calculations were performed in each room size with the three source particle types. Coefficients for the noble gas radionuclides of ICRP Publication 107 (e.g., Ne, Ar, Kr, Xe, and Rn) were generated by folding the corresponding photon, electron, and positron emissions over the mono-energetic dose rate coefficients. Results indicate that the smaller room sizes have a significant impact on the dose rate per unit air concentration compared to the semi-infinite cloud case. For example, for Kr-85 the warehouse dose rate coefficient is 7% higher than the office dose rate coefficient while it is 71% higher for Xe-133. (orig.)

  13. Methods for Predicting Tail Control Effects on Conical Afterbodies of Submersibles

    Science.gov (United States)

    1982-08-01

    vehicles have not received the attention they warrant. It is dea3irable to develop such methods to avoid expensive and time- comsuming parametric studies of...data except for the PR = 0.5 fin very well. The M = 0.5 fin gave a very large value of kT as well as a very rearward (x c/c r)T(). This behavior ...lines could be made to fit the data within the scatter bands with good accuracy. However, it was found that the s/R family exhibited quadratic behavior

  14. Small Submersible Robust Microflow Cytometer for Quantitative Detection of Phytoplankton, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Marine phytoplankton are critical in sustaining life on Earth. They are key drivers of the global biogeochemical cycles of carbon and other nutrients, and account...

  15. Submersed sensing electrode used in fuel-cell type hydrogen detector

    Science.gov (United States)

    Niedrach, L. W.; Rudek, F. P.; Rutkoneski, M. D.

    1971-01-01

    Electrode has silicone rubber diffusion barrier with fixed permeation constant for hydrogen. Barrier controls flow of hydrogen to anode and Faraday relationship establishes upper limit for current through cell. Electrode fabrication is described.

  16. Carbon-Flow-Based Modeling of Ecophysiological Processes and Biomass Dynamics of Submersed Aquatic Plants

    Science.gov (United States)

    2007-09-01

    availability of tuber growth data was insufficient. A translocation rate of 19 percent of net photosynthesis , typical for the related seagrasses (Wetzel and...20 Figure 4. Relational diagram illustrating photosynthesis , respiration, and biomass...rate of CO2 assimilation ( photosynthesis ) of the SAV community depends on the radi- ant energy absorbed by the canopy, which is a function of

  17. Transitioning Submersible Chemical Analyzer Technologies for Sustained, Autonomous Observations From Profiling Moorings, Gliders and other AUVs

    National Research Council Canada - National Science Library

    Hanson, Alfred K; Donaghay, Percy L; Moore, Casey; Arrieta, Richard

    2006-01-01

    The long term goal is to transition existing prototype autonomous profiling nutrient analyzers into commercial products that can be readily deployed on autonomous profiling moorings, coastal gliders...

  18. Design and analysis of a semi-submersible vertical axis wind turbine

    OpenAIRE

    Siddique, Muhammad Abu Zafar

    2017-01-01

    Wind energy are deployed by two types of wind turbines. They are Horizontal Axis Wind Turbine (HAWT) and Vertical Axis Wind Turbine (VAWT), classified according to their axis of rotation. In recent years, offshore wind energy playing a vital role in the wind turbine industry due to high intensity of air, less turbulent and comparatively clean and easily employed in large area which is difficult to manage for onshore or near-shore. The advantages of HAWTs are now facing different challenge in ...

  19. Aquatic Plant Control Research Program. Growth and Rooting Depth Characteristics of Hydrilla Verticillata (L.f.) Royle and Myriophyllum Spicatum L. on Fertilized and Unfertilized Sediments

    Science.gov (United States)

    1994-05-01

    originally collected from natural populations-Myriophyllun, from Lake Wingra, Wisconsin, and Hydri ~la, from the Potomac River, Virginia. The two...species by influencing the mass of sediment nutri- ents available for growth. Notably, the high production levels in Myriophyllwn and Hydri //a on N-rich...sharing the same letter (upper case for Hydri //a and lower case for yrnophy/um) do not differ significantly. Asterisk denotes values that are

  20. Improvements in the use of aquatic herbicides and establishment of future research directions

    Science.gov (United States)

    Getsinger, K.D.; Netherland, M.D.; Grue, C.E.; Koschnick, T.J.

    2008-01-01

    Peer-reviewed literature over the past 20 years identifies significant changes and improvements in chemical control strategies used to manage nuisance submersed vegetation. The invasive exotic plants hydrilla (Hydrilla verticillata L.f. Royle) and Eurasian watermilfoil (Myriophyllum spicatum L.) continue to spread and remain the plant species of greatest concern for aquatic resource managers at the national scale. Emerging exotic weeds of regional concern such as egeria (Egeria densa Planch.), curlyleaf pondweed (Potamogeton crispus L.), and hygrophila (Hygrophila polysperma (Roxb.) T. Anders), as well as native plants such as variable watermilfoil (Myriophyllum heterophyllum Michx), and cabomba (Cabomba caroliniana Gray) are invasive outside their home ranges. In addition, there is always the threat of new plant introductions such as African elodea (Lagarosiphon major (Ridley) Moss) or narrow-leaf anacharis (Egeria najas Planchon). The registration of the bleaching herbicide fluridone in the mid 1980s for whole-lake and large-scale management stimulated numerous lines of research involving reduction of use rates, plant selectivity, residue monitoring, and impacts on fisheries. In addition to numerous advances, the specificity of fluridone for a single plant enzyme led to the first documented case of herbicide resistance in aquatic plant management. The resistance of hydrilla to fluridone has stimulated a renewed interest by industry and others in the registration of alternative modes of action for aquatic use. These newer chemistries tend to be enzyme-specific compounds with favorable non-target toxicity profiles. Registration efforts have been facilitated by increased cooperation between key federal government agencies that have aquatic weed control and research responsibilities, and regulators within the U.S. Environmental Protection Agency (USEPA). We reviewed past and current research efforts to identify areas in need of further investigation and to establish

  1. Mesohaline submerged aquatic vegetation survey along the U.S. gulf of Mexico coast, 2001 and 2002: A salinity gradient approach

    Science.gov (United States)

    Merino, J.H.; Carter, J.; Merino, S.L.

    2009-01-01

    Distribution of marine submerged aquatic vegetation (SAV; i.e., seagrass) in the northern Gulf of Mexico coast has been documented, but there are nonmarine submersed or SAV species occurring in estuarine salinities that have not been extensively reported. We sampled 276 SAV beds along the gulf coast in Florida, Alabama, Mississippi, Louisiana, and Texas in 2001 and 2002 in oligohaline to polyhaline (0 to 36 parts per thousand) waters to determine estuarine SAV species distribution and identify mesohaline SAV communities. A total of 20 SAV and algal species was identified and habitat characteristics such as salinity, water depth, pH, conductivity, turbidity, dissolved oxygen, and sediment composition were collected. Fourteen SAV species occurred two or more times in our samples. The most frequently occurring species was Ruppia maritima L. (n = 148), occurring in over half of SAV beds sampled. Eleocharis sp. (n = 47), characterized with an emergent rather than submerged growth form, was a common genus in the SAV beds sampled. A common marine species was Halodule wrightii Asch. (n = 36). Nonindigenous species Myriophyllum spicatum L. (n = 31) and Hydrilla verticillata (L. f.) Royle (n = 6) were present only in oligohaline water. Analyzing species occurrence and environmental characteristics using canonical correspondence and two-way indicator species analysis, we identify five species assemblages distinguished primarily by salinity and depth. Our survey increases awareness of nonmarine SAV as a natural resource in the gulf, and provides baseline data for future research. ?? 2009 by the Marine Environmental Sciences Consortium of Alabama.

  2. Phytotoxical effect of Lepidium draba L. extracts on the germination and growth of monocot (Zea mays L.) and dicot (Amaranthus retroflexus L.) seeds.

    Science.gov (United States)

    Kaya, Yusuf; Aksakal, Ozkan; Sunar, Serap; Erturk, Filiz Aygun; Bozari, Sedat; Agar, Guleray; Erez, Mehmet Emre; Battal, Peyami

    2015-03-01

    Laboratory experiments were performed to determine phytotoxic potentials of white top (Lepidium draba) methanol extracts (root, stem and leaf) on germination and early growth of corn (Zea mays) and redroot pigweed (Amaranthus retroflexus). Furthermore, the effects of different methanol extracts of L. draba on the phytohormone (indole-3-acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA) and zeatin) levels of corn and redroot pigweed were investigated. It was observed that all concentrations of methanol extracts of root, stem and leaf of L. draba inhibited germination, radicle and plumule elongation when compared with the respective controls. Besides this, the degree of inhibition was increased in concert with increasing concentrations of extracts used. On the other hand, phytohormone levels changed with the application of different extract concentrations. Comparing with the control, the GA levels significantly decreased while the ABA levels increased in all the application groups. Zeatin and IAA levels showed changes depending upon the applied extracts and concentrations. © The Author(s) 2012.

  3. A comparative study of ethylene growth response kinetics in eudicots and monocots reveals a role for gibberellin in growth inhibition and recovery.

    Science.gov (United States)

    Kim, Joonyup; Wilson, Rebecca L; Case, J Brett; Binder, Brad M

    2012-11-01

    Time-lapse imaging of dark-grown Arabidopsis (Arabidopsis thaliana) hypocotyls has revealed new aspects about ethylene signaling. This study expands upon these results by examining ethylene growth response kinetics of seedlings of several plant species. Although the response kinetics varied between the eudicots studied, all had prolonged growth inhibition for as long as ethylene was present. In contrast, with continued application of ethylene, white millet (Panicum miliaceum) seedlings had a rapid and transient growth inhibition response, rice (Oryza sativa 'Nipponbare') seedlings had a slow onset of growth stimulation, and barley (Hordeum vulgare) had a transient growth inhibition response followed, after a delay, by a prolonged inhibition response. Growth stimulation in rice correlated with a decrease in the levels of rice ETHYLENE INSENSTIVE3-LIKE2 (OsEIL2) and an increase in rice F-BOX DOMAIN AND LRR CONTAINING PROTEIN7 transcripts. The gibberellin (GA) biosynthesis inhibitor paclobutrazol caused millet seedlings to have a prolonged growth inhibition response when ethylene was applied. A transient ethylene growth inhibition response has previously been reported for Arabidopsis ethylene insensitive3-1 (ein3-1) eil1-1 double mutants. Paclobutrazol caused these mutants to have a prolonged response to ethylene, whereas constitutive GA signaling in this background eliminated ethylene responses. Sensitivity to paclobutrazol inversely correlated with the levels of EIN3 in Arabidopsis. Wild-type Arabidopsis seedlings treated with paclobutrazol and mutants deficient in GA levels or signaling had a delayed growth recovery after ethylene removal. It is interesting to note that ethylene caused alterations in gene expression that are predicted to increase GA levels in the ein3-1 eil1-1 seedlings. These results indicate that ethylene affects GA levels leading to modulation of ethylene growth inhibition kinetics.

  4. Global history of the ancient monocot family Araceae inferred with models accounting for past continental positions and previous ranges based on fossils.

    Science.gov (United States)

    Nauheimer, Lars; Metzler, Dirk; Renner, Susanne S

    2012-09-01

    The family Araceae (3790 species, 117 genera) has one of the oldest fossil records among angiosperms. Ecologically, members of this family range from free-floating aquatics (Pistia and Lemna) to tropical epiphytes. Here, we infer some of the macroevolutionary processes that have led to the worldwide range of this family and test how the inclusion of fossil (formerly occupied) geographical ranges affects biogeographical reconstructions. Using a complete genus-level phylogeny from plastid sequences and outgroups representing the 13 other Alismatales families, we estimate divergence times by applying different clock models and reconstruct range shifts under different models of past continental connectivity, with or without the incorporation of fossil locations. Araceae began to diversify in the Early Cretaceous (when the breakup of Pangea was in its final stages), and all eight subfamilies existed before the K/T boundary. Early lineages persist in Laurasia, with several relatively recent entries into Africa, South America, South-East Asia and Australia. Water-associated habitats appear to be ancestral in the family, and DNA substitution rates are especially high in free-floating Araceae. Past distributions inferred when fossils are included differ in nontrivial ways from those without fossils. Our complete genus-level time-scale for the Araceae may prove to be useful for ecological and physiological studies. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  5. A Comparative Study of Ethylene Growth Response Kinetics in Eudicots and Monocots Reveals a Role for Gibberellin in Growth Inhibition and Recovery1[W][OA

    Science.gov (United States)

    Kim, Joonyup; Wilson, Rebecca L.; Case, J. Brett; Binder, Brad M.

    2012-01-01

    Time-lapse imaging of dark-grown Arabidopsis (Arabidopsis thaliana) hypocotyls has revealed new aspects about ethylene signaling. This study expands upon these results by examining ethylene growth response kinetics of seedlings of several plant species. Although the response kinetics varied between the eudicots studied, all had prolonged growth inhibition for as long as ethylene was present. In contrast, with continued application of ethylene, white millet (Panicum miliaceum) seedlings had a rapid and transient growth inhibition response, rice (Oryza sativa ‘Nipponbare’) seedlings had a slow onset of growth stimulation, and barley (Hordeum vulgare) had a transient growth inhibition response followed, after a delay, by a prolonged inhibition response. Growth stimulation in rice correlated with a decrease in the levels of rice ETHYLENE INSENSTIVE3-LIKE2 (OsEIL2) and an increase in rice F-BOX DOMAIN AND LRR CONTAINING PROTEIN7 transcripts. The gibberellin (GA) biosynthesis inhibitor paclobutrazol caused millet seedlings to have a prolonged growth inhibition response when ethylene was applied. A transient ethylene growth inhibition response has previously been reported for Arabidopsis ethylene insensitive3-1 (ein3-1) eil1-1 double mutants. Paclobutrazol caused these mutants to have a prolonged response to ethylene, whereas constitutive GA signaling in this background eliminated ethylene responses. Sensitivity to paclobutrazol inversely correlated with the levels of EIN3 in Arabidopsis. Wild-type Arabidopsis seedlings treated with paclobutrazol and mutants deficient in GA levels or signaling had a delayed growth recovery after ethylene removal. It is interesting to note that ethylene caused alterations in gene expression that are predicted to increase GA levels in the ein3-1 eil1-1 seedlings. These results indicate that ethylene affects GA levels leading to modulation of ethylene growth inhibition kinetics. PMID:22977279

  6. Terrestrial 3D laser scanning to track the increase in canopy height of both monocot and dicot crop species under field conditions.

    Science.gov (United States)

    Friedli, Michael; Kirchgessner, Norbert; Grieder, Christoph; Liebisch, Frank; Mannale, Michael; Walter, Achim

    2016-01-01

    Plant growth is a good indicator of crop performance and can be measured by different methods and on different spatial and temporal scales. In this study, we measured the canopy height growth of maize (Zea mays), soybean (Glycine max) and wheat (Triticum aestivum) under field conditions by terrestrial laser scanning (TLS). We tested the hypotheses whether such measurements are capable to elucidate (1) differences in architecture that exist between genotypes; (2) genotypic differences between canopy height growth during the season and (3) short-term growth fluctuations (within 24 h), which could e.g. indicate responses to rapidly fluctuating environmental conditions. The canopies were scanned with a commercially available 3D laser scanner and canopy height growth over time was analyzed with a novel and simple approach using spherical targets with fixed positions during the whole season. This way, a high precision of the measurement was obtained allowing for comparison of canopy parameters (e.g. canopy height growth) at subsequent time points. Three filtering approaches for canopy height calculation from TLS were evaluated and the most suitable approach was used for the subsequent analyses. For wheat, high coefficients of determination (R(2)) of the linear regression between manually measured and TLS-derived canopy height were achieved. The temporal resolution that can be achieved with our approach depends on the scanned crop. For maize, a temporal resolution of several hours can be achieved, whereas soybean is ideally scanned only once per day, after leaves have reached their most horizontal orientation. Additionally, we could show for maize that plant architectural traits are potentially detectable with our method. The TLS approach presented here allows for measuring canopy height growth of different crops under field conditions with a high temporal resolution, depending on crop species. This method will enable advances in automated phenotyping for breeding and precision agriculture applications. In future studies, the TLS method can be readily applied to detect the effects of plant stresses such as drought, limited nutrient availability or compacted soil on different genotypes or on spatial variance in fields.

  7. Active Sites of Reduced Epidermal Fluorescence1 (REF1) Isoforms Contain Amino Acid Substitutions That Are Different between Monocots and Dicots.

    Science.gov (United States)

    Missihoun, Tagnon D; Kotchoni, Simeon O; Bartels, Dorothea

    2016-01-01

    Plant aldehyde dehydrogenases (ALDHs) play important roles in cell wall biosynthesis, growth, development, and tolerance to biotic and abiotic stresses. The Reduced Epidermal Fluorescence1 is encoded by the subfamily 2C of ALDHs and was shown to oxidise coniferaldehyde and sinapaldehyde to ferulic acid and sinapic acid in the phenylpropanoid pathway, respectively. This knowledge has been gained from works in the dicotyledon model species Arabidopsis thaliana then used to functionally annotate ALDH2C isoforms in other species, based on the orthology principle. However, the extent to which the ALDH isoforms differ between monocotyledons and dicotyledons has rarely been accessed side-by-side. In this study, we used a phylogenetic approach to address this question. We have analysed the ALDH genes in Brachypodium distachyon, alongside those of other sequenced monocotyledon and dicotyledon species to examine traits supporting either a convergent or divergent evolution of the ALDH2C/REF1-type proteins. We found that B. distachyon, like other grasses, contains more ALDH2C/REF1 isoforms than A. thaliana and other dicotyledon species. Some amino acid residues in ALDH2C/REF1 isoforms were found as being conserved in dicotyledons but substituted by non-equivalent residues in monocotyledons. One example of those substitutions concerns a conserved phenylalanine and a conserved tyrosine in monocotyledons and dicotyledons, respectively. Protein structure modelling suggests that the presence of tyrosine would widen the substrate-binding pocket in the dicotyledons, and thereby influence substrate specificity. We discussed the importance of these findings as new hints to investigate why ferulic acid contents and cell wall digestibility differ between the dicotyledon and monocotyledon species.

  8. Active Sites of Reduced Epidermal Fluorescence1 (REF1 Isoforms Contain Amino Acid Substitutions That Are Different between Monocots and Dicots.

    Directory of Open Access Journals (Sweden)

    Tagnon D Missihoun

    Full Text Available Plant aldehyde dehydrogenases (ALDHs play important roles in cell wall biosynthesis, growth, development, and tolerance to biotic and abiotic stresses. The Reduced Epidermal Fluorescence1 is encoded by the subfamily 2C of ALDHs and was shown to oxidise coniferaldehyde and sinapaldehyde to ferulic acid and sinapic acid in the phenylpropanoid pathway, respectively. This knowledge has been gained from works in the dicotyledon model species Arabidopsis thaliana then used to functionally annotate ALDH2C isoforms in other species, based on the orthology principle. However, the extent to which the ALDH isoforms differ between monocotyledons and dicotyledons has rarely been accessed side-by-side. In this study, we used a phylogenetic approach to address this question. We have analysed the ALDH genes in Brachypodium distachyon, alongside those of other sequenced monocotyledon and dicotyledon species to examine traits supporting either a convergent or divergent evolution of the ALDH2C/REF1-type proteins. We found that B. distachyon, like other grasses, contains more ALDH2C/REF1 isoforms than A. thaliana and other dicotyledon species. Some amino acid residues in ALDH2C/REF1 isoforms were found as being conserved in dicotyledons but substituted by non-equivalent residues in monocotyledons. One example of those substitutions concerns a conserved phenylalanine and a conserved tyrosine in monocotyledons and dicotyledons, respectively. Protein structure modelling suggests that the presence of tyrosine would widen the substrate-binding pocket in the dicotyledons, and thereby influence substrate specificity. We discussed the importance of these findings as new hints to investigate why ferulic acid contents and cell wall digestibility differ between the dicotyledon and monocotyledon species.

  9. Plant growth-promoting bacterium Acinetobacter calcoaceticus P23 increases the chlorophyll content of the monocot Lemna minor (duckweed) and the dicot Lactuca sativa (lettuce).

    Science.gov (United States)

    Suzuki, Wakako; Sugawara, Masayuki; Miwa, Kyoko; Morikawa, Masaaki

    2014-07-01

    Acinetobacter calcoaceticus P23 is a plant growth-promoting bacterium that was isolated from the surface of duckweed (Lemna aoukikusa). The bacterium was observed to colonize on the plant surfaces and increase the chlorophyll content of not only the monocotyledon Lemna minor but also the dicotyledon Lactuca sativa in a hydroponic culture. This effect on the Lactuca sativa was significant in nutrient-poor (×1/100 dilution of H2 medium) and not nutrient-rich (×1 or ×1/10 dilutions of H2 medium) conditions. Strain P23 has the potential to play a part in the future development of fertilizers and energy-saving hydroponic agricultural technologies. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  10. A Phylogeny of the Monocots, as Inferred from rbcL and atpA Sequence Variation, and a Comparison of Methods for Calculating Jackknife and Bootstrap Values

    DEFF Research Database (Denmark)

    Davis, Jerrold I.; Stevenson, Dennis W.; Petersen, Gitte

    2004-01-01

    elements of Xyridaceae. A comparison was conducted of jackknife and bootstrap values, as computed using strict-consensus (SC) and frequency-within-replicates (FWR) approaches. Jackknife values tend to be higher than bootstrap values, and for each of these methods support values obtained with the FWR...

  11. State of South Carolina Cooperative Aquatic Plant Control Program.

    Science.gov (United States)

    1980-11-01

    of a diquat and copper sulfate pentahydrate herbicide combination for hydrilla control was carried out by Yeo et. al. (1974). The copper was applied at...effective combination to control egeria and hydrilla (Gangstad, 1976). A diquat- copper sulfate combination is more effective in controlling hydrilla than the... copper resulting from the use of algacides or herbicides basic copper carbonate (malachite), copper sulfate , and copper tri- ethanolamine to control

  12. A Survey of the Invasive Aquatic and Riparian Plants of the Lower Rio Grande

    National Research Council Canada - National Science Library

    Owens, Chetta S; Grodowitz, Michael J; Nibling, Fred

    2005-01-01

    .... In 2001 and 2003, surveys were conducted starting below Amistad Reservoir to immediately below Falcon Reservoir to assess the distribution and expansion of the hydrilla infestations and document...

  13. A Survey of the Invasive Aquatic and Riparian Plants of the Lower Rio Grande, 2004

    National Research Council Canada - National Science Library

    Owens, Chetta S; Grodowitz, Michael J; Nibling, Fred

    2005-01-01

    .... In 2004, surveys were conducted starting below Amistad Reservoir to immediately below Falcon Reservoir to assess the distribution and expansion of hydrilla infestations and document the presence...

  14. A Survey of the Invasive Aquatic and Riparian Plants of the Low Rio Grande

    National Research Council Canada - National Science Library

    Owens, Chetta S; Grodowitz, Michael J; Nibling, Fred

    2005-01-01

    .... In 2001 and 2003, surveys were conducted starting below Amistad Reservoir to immediately below Falcon Reservoir to assess the distribution and expansion of the hydrilla infestations and document...

  15. Design, Numerical Modelling and Analysis of a Semi-submersible Floater Supporting the DTU 10MW Wind Turbine.

    OpenAIRE

    Islam, Md Touhidul

    2016-01-01

    In recent years, the demand for renewable energy has increased significantly because of its lower environmental impact than conventional energy technologies. Wind power is one of the most important sources of renewable energy produced nowadays. As land based turbines have reached their maximum potential, recent market trends are moving into deeper waters with higher capacity turbines. The design of a floating offshore wind turbine (FOWT) foundation poses few technical challenges....

  16. A Comprehensive Inventory of Alabama Coastal Zone Wetland Habitats (Swamps, Marshes, Submersed Grassbeds) from 1980 to 1982 (NCEI Accession 0161311)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitized maps of Mobile Bay and other coastal areas of Alabama, showing habitat types and species compositions of the vegetation in three broad categories of...

  17. Beyond harm's reach? Submersion of river turtle nesting areas and implications for restoration actions after Amazon hydropower development.

    Science.gov (United States)

    Norris, Darren; Michalski, Fernanda; Gibbs, James P

    2018-01-01

    The global expansion of energy demands combined with abundant rainfall, large water volumes and high flow in tropical rivers have led to an unprecedented expansion of dam constructions in the Amazon. This expansion generates an urgent need for refined approaches to river management; specifically a move away from decision-making governed by overly generalized guidelines. For the first time we quantify direct impacts of hydropower reservoir establishment on an Amazon fresh water turtle. We conducted surveys along 150 km of rivers upstream of a new dam construction during the low water months that correspond to the nesting season of Podocnemis unifilis in the study area. Comparison of nest-areas before (2011, 2015) and after (2016) reservoir filling show that reservoir impacts extend 13% beyond legally defined limits. The submerged nesting areas accounted for a total of 3.8 ha of nesting habitat that was inundated as a direct result of the reservoir filling in 2016. Our findings highlight limitations in the development and implementation of existing Brazilian environmental impact assessment process. We also propose potential ways to mitigate the negative impacts of dams on freshwater turtles and the Amazonian freshwater ecosystems they inhabit.

  18. Beyond harm’s reach? Submersion of river turtle nesting areas and implications for restoration actions after Amazon hydropower development

    Science.gov (United States)

    Michalski, Fernanda; Gibbs, James P.

    2018-01-01

    The global expansion of energy demands combined with abundant rainfall, large water volumes and high flow in tropical rivers have led to an unprecedented expansion of dam constructions in the Amazon. This expansion generates an urgent need for refined approaches to river management; specifically a move away from decision-making governed by overly generalized guidelines. For the first time we quantify direct impacts of hydropower reservoir establishment on an Amazon fresh water turtle. We conducted surveys along 150 km of rivers upstream of a new dam construction during the low water months that correspond to the nesting season of Podocnemis unifilis in the study area. Comparison of nest-areas before (2011, 2015) and after (2016) reservoir filling show that reservoir impacts extend 13% beyond legally defined limits. The submerged nesting areas accounted for a total of 3.8 ha of nesting habitat that was inundated as a direct result of the reservoir filling in 2016. Our findings highlight limitations in the development and implementation of existing Brazilian environmental impact assessment process. We also propose potential ways to mitigate the negative impacts of dams on freshwater turtles and the Amazonian freshwater ecosystems they inhabit. PMID:29333347

  19. A simple and rapid method for monitoring dissolved oxygen in water with a submersible microbial fuel cell (SBMFC)

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2012-01-01

    Asubmersiblemicrobial fuel cell (SBMFC) was developed as a biosensor forin situand real time monitoring of dissolvedoxygen (DO) in environmental waters. Domestic wastewater was utilized as sole fuel for powering the sensor. The sensor performance was firstly examined with tap water at varying DO...... the sensing activities. The sensor ability was further explored under different environmental conditions (e.g., pH, temperature, conductivity, alternative electron acceptor), and the results indicated that a calibration would be required before field application. Lastly, the sensor was tested with different...

  20. 78 FR 40891 - Revisions to the Export Administration Regulations: Military Vehicles; Vessels of War...

    Science.gov (United States)

    2013-07-08

    ... Vehicles; Vessels of War; Submersible Vessels, Oceanographic Equipment; Related Items; and Auxiliary and... Regulations: Military Vehicles; Vessels of War; Submersible Vessels, Oceanographic Equipment; Related Items... military vehicles and related items; vessels of war and related items; submersible vessels, oceanographic...

  1. Overexpression of the Synthetic Chimeric Native-T-phylloplanin-GFP Genes Optimized for Monocot and Dicot Plants Renders Enhanced Resistance to Blue Mold Disease in Tobacco (N. tabacum L.

    Directory of Open Access Journals (Sweden)

    Dipak K. Sahoo

    2014-01-01

    Full Text Available To enhance the natural plant resistance and to evaluate the antimicrobial properties of phylloplanin against blue mold, we have expressed a synthetic chimeric native-phylloplanin-GFP protein fusion in transgenic Nicotiana tabacum cv. KY14, a cultivar that is highly susceptible to infection by Peronospora tabacina. The coding sequence of the tobacco phylloplanin gene along with its native signal peptide was fused with GFP at the carboxy terminus. The synthetic chimeric gene (native-phylloplanin-GFP was placed between the modified Mirabilis mosaic virus full-length transcript promoter with duplicated enhancer domains and the terminator sequence from the rbcSE9 gene. The chimeric gene, expressed in transgenic tobacco, was stably inherited in successive plant generations as shown by molecular characterization, GFP quantification, and confocal fluorescent microscopy. Transgenic plants were morphologically similar to wild-type plants and showed no deleterious effects due to transgene expression. Blue mold-sensitivity assays of tobacco lines were performed by applying P. tabacina sporangia to the upper leaf surface. Transgenic lines expressing the fused synthetic native-phyllopanin-GFP gene in the leaf apoplast showed resistance to infection. Our results demonstrate that in vivo expression of a synthetic fused native-phylloplanin-GFP gene in plants can potentially achieve natural protection against microbial plant pathogens, including P. tabacina in tobacco.

  2. ZmPUMP encodes a fully functional monocot plant uncoupling mitochondrial protein whose affinity to fatty acid is increased with the introduction of a His pair at the second matrix loop

    International Nuclear Information System (INIS)

    Favaro, Regiane Degan; Borecky, Jiri; Colombi, Debora; Maia, Ivan G.

    2006-01-01

    Uncoupling proteins (UCPs) are specialized mitochondrial transporter proteins that uncouple respiration from ATP synthesis. In this study, cDNA encoding maize uncoupling protein (ZmPUMP) was expressed in Escherichia coli and recombinant ZmPUMP reconstituted in liposomes. ZmPUMP activity was associated with a linoleic acid (LA)-mediated H + efflux with K m of 56.36 ± 0.27 μM and V max of 66.9 μmol H + min -1 (mg prot) -1 . LA-mediated H + fluxes were sensitive to ATP inhibition with K i of 2.61 ± 0.36 mM (at pH 7.2), a value similar to those for dicot UCPs. ZmPUMP was also used to investigate the importance of a histidine pair present in the second matrix loop of mammalian UCP1 and absent in plant UCPs. ZmPUMP with introduced His pair (Lys155His and Ala157His) displayed a 1.55-fold increase in LA-affinity while its activity remained unchanged. Our data indicate conserved properties of plant UCPs and suggest an enhancing but not essential role of the histidine pair in proton transport mechanism

  3. Chapman's Reef Oculina Banks Clelia Dive 621 2001 Digital Imagery - Captured from Videotapes taken during Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitial imagery, mpegs and jpegs, captured from mini-DV magnetic videotapes collected with an underwater 3-chip CCD color video camera, deployed from the research...

  4. Sebastian Pinnacles, Oculina Banks Clelia Dive 615 2001 Digital Imagery - Captured from Videotapes taken during Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitial imagery, mpegs and jpegs, captured from mini-DV magnetic videotapes collected with an underwater 3-chip CCD color video camera, deployed from the research...

  5. Sebastian Pinnacles Oculina Banks Clelia Dive 619 2001 Digital Imagery - Captured from Videotapes taken during Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitial imagery, mpegs and jpegs, captured from mini-DV magnetic videotapes collected with an underwater 3-chip CCD color video camera, deployed from the research...

  6. Sebastian Pinnacles Oculina Banks Clelia Dive 618 2001 Digital Imagery - Captured from Videotapes taken during Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitial imagery, mpegs and jpegs, captured from mini-DV magnetic videotapes collected with an underwater 3-chip CCD color video camera, deployed from the research...

  7. Sebastian Pinnacles, Oculina Banks Clelia Dive 614 2001 Digital Imagery - Captured from Videotapes taken during Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitial imagery, mpegs and jpegs, captured from mini-DV magnetic videotapes collected with an underwater 3-chip CCD color video camera, deployed from the research...

  8. Development and field tests of GEM, the Ocean's Kite: A submersible floating device to tap tidal current energy

    International Nuclear Information System (INIS)

    Coiro, Domenico P.; Bizzarrini, Nadia; Calise Giuseppe; Troise, Giancarlo; Scherillo, Ferdinando

    2015-01-01

    This paper presents the results of a series of test campaigns performed on an innovative system to harness clean energy from marine and river currents, developed in cooperation with the University of Naples “Federico II”. It consists of an underwater vehicle linked to the seabed by means of a tether and supporting two hydro-turbines. Preliminary studies and experimental results of wind tunnel and towing tank tests on both single turbine and a complete scaled model will be illustrated. The behavior and performances of different configurations in both nominal and off-design conditions will be highlighted. Finally experimental results on a full-scale prototype installed in the Venetian lagoon will be presented [it

  9. A comparison of extreme structural responses and fatigue damage of semi-submersible type floating horizontal and vertical axis wind turbines

    DEFF Research Database (Denmark)

    Cheng, Zhengshun; Aagaard Madsen, Helge; Chai, Wei

    2017-01-01

    •A comprehensive comparison of floating HAWTs and VAWTs with different blade number.•Extreme structural responses and fatigue damage are studied.•Both operational and parked conditions are considered.•The merits and disadvantages of floating HAWTs and VAWTs are revealed and highlighted.......•A comprehensive comparison of floating HAWTs and VAWTs with different blade number.•Extreme structural responses and fatigue damage are studied.•Both operational and parked conditions are considered.•The merits and disadvantages of floating HAWTs and VAWTs are revealed and highlighted....

  10. Jeff's Reef Oculina Banks Clelia Dive 606 2001 Digital Imagery - Captured from Videotapes taken during Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitial imagery, mpegs and jpegs, captured from mini-DV magnetic videotapes collected with an underwater 3-chip CCD color video camera, deployed from the research...

  11. Eau Galllie Oculina Banks Clelia Dive 609 2001 Digital Imagery - Captured from Videotapes tken during Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitial imagery, mpegs and jpegs, captured from mini-DV magnetic videotapes collected with an underwater 3-chip CCD color video camera, deployed from the research...

  12. Fish but Not Macroinvertebrates Promote Trophic Cascading Effects in High Density Submersed Plant Experimental Lake Food Webs in Two Contrasting Climate Regions

    Directory of Open Access Journals (Sweden)

    Carlos Iglesias

    2017-07-01

    Full Text Available Predators play a key role in the functioning of shallow lakes. Differences between the response of temperate and subtropical systems to fish predation have been proposed, but experimental evidence is scarce. To elucidate cascading effects produced by predators in contrasting climatic zones, we conducted a mesocosm experiment in three pairs of lakes in Uruguay and Denmark. We used two typical planktivorous-omnivorous fish species (Jenynsia multidentata + Cnesterodon decemmaculatus and Gasterosteus aculeatus + Perca fluviatilis and one littoral omnivorous-predatory macroinvertebrate (Palaemonetes argentinus and Gammarus lacustris, alone and combined, in numbers resembling natural densities. Fish predation on zooplankton increased phytoplankton biomass in both climate zones, whereas the effects of predatory macroinvertebrates on zooplankton and phytoplankton were not significant in either climate zone. Macroinvertebrates (that freely colonized the sampling devices were diminished by fish in both climate areas; however, periphyton biomass did not vary among treatments. Our experiments demonstrated that fish affected the structure of both planktonic and littoral herbivorous communities in both climate regions, with a visible positive cascading effect on phytoplankton biomass, but no effects on periphyton. Altogether, fish impacts appeared to be a strong driver of turbid water conditions in shallow lakes regardless of climatic zone by indirectly contributing to increasing phytoplankton biomass.

  13. External dose-rate conversion factors of radionuclides for air submersion, ground surface contamination and water immersion based on the new ICRP dosimetric setting.

    Science.gov (United States)

    Yoo, Song Jae; Jang, Han-Ki; Lee, Jai-Ki; Noh, Siwan; Cho, Gyuseong

    2013-01-01

    For the assessment of external doses due to contaminated environment, the dose-rate conversion factors (DCFs) prescribed in Federal Guidance Report 12 (FGR 12) and FGR 13 have been widely used. Recently, there were significant changes in dosimetric models and parameters, which include the use of the Reference Male and Female Phantoms and the revised tissue weighting factors, as well as the updated decay data of radionuclides. In this study, the DCFs for effective and equivalent doses were calculated for three exposure settings: skyshine, groundshine and water immersion. Doses to the Reference Phantoms were calculated by Monte Carlo simulations with the MCNPX 2.7.0 radiation transport code for 26 mono-energy photons between 0.01 and 10 MeV. The transport calculations were performed for the source volume within the cut-off distances practically contributing to the dose rates, which were determined by a simplified calculation model. For small tissues for which the reduction of variances are difficult, the equivalent dose ratios to a larger tissue (with lower statistical errors) nearby were employed to make the calculation efficient. Empirical response functions relating photon energies, and the organ equivalent doses or the effective doses were then derived by the use of cubic-spline fitting of the resulting doses for 26 energy points. The DCFs for all radionuclides considered important were evaluated by combining the photon emission data of the radionuclide and the empirical response functions. Finally, contributions of accompanied beta particles to the skin equivalent doses and the effective doses were calculated separately and added to the DCFs. For radionuclides considered in this study, the new DCFs for the three exposure settings were within ±10 % when compared with DCFs in FGR 13.

  14. Effects of water turbulence on variations in cell ultrastructure and metabolism of amino acids in the submersed macrophyte, Elodea nuttallii (Planch.) H. St. John.

    Science.gov (United States)

    Atapaththu, K S S; Miyagi, A; Atsuzawa, K; Kaneko, Y; Kawai-Yamada, M; Asaeda, T

    2015-09-01

    The interactions between macrophytes and water movement are not yet fully understood, and the causes responsible for the metabolic and ultrastructural variations in plant cells as a consequence of turbulence are largely unknown. In the present study, growth, metabolism and ultrastructural changes were evaluated in the aquatic macrophyte Elodea nuttallii, after exposure to turbulence for 30 days. The turbulence was generated with a vertically oscillating horizontal grid. The turbulence reduced plant growth, plasmolysed leaf cells and strengthened cell walls, and plants exposed to turbulence accumulated starch granules in stem chloroplasts. The size of the starch granules increased with the magnitude of the turbulence. Using capillary electrophoresis-mass spectrometry (CE-MS), analysis of the metabolome found metabolite accumulation in response to the turbulence. Asparagine was the dominant amino acid that was concentrated in stressed plants, and organic acids such as citrate, ascorbate, oxalate and γ-amino butyric acid (GABA) also accumulated in response to turbulence. These results indicate that turbulence caused severe stress that affected plant growth, cell ultrastructure and some metabolic functions of E. nuttallii. Our findings offer insights to explain the effects of water movement on the functions of aquatic plants. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  15. Cocoa Beach Oculina Banks Clelia Dive 617 2001 Digital Imagery - Captured from Videotapes taken during Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitial imagery, mpegs and jpegs, captured from mini-DV magnetic videotapes collected with an underwater 3-chip CCD color video camera, deployed from the research...

  16. Cape Canaveral Oculina Banks Clelia Dive 616 2001 Digital Imagery - Captured from Videotapes taken during Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitial imagery, mpegs and jpegs, captured from mini-DV magnetic videotapes collected with an underwater 3-chip CCD color video camera, deployed from the research...

  17. 1998 Annual Status Report: Submersed and Floating-Leaf Vegetation in Pools 4, 8, 13, and 26 and La Grange Pool of the Upper Mississippi River System

    National Research Council Canada - National Science Library

    Yin, Yao

    2001-01-01

    Aquatic vegetation was investigated in five navigation pools in the Upper Mississippi River System using a new protocol named 'stratified random sampling' or SRS protocol for the first time in 1998...

  18. Computer simulating for oil fields with artificial elevation method by electrical submersible pump; Simulacao computacional para pocos de petroleo com metodo de elevacao artificial por bombeio centrifugo submerso

    Energy Technology Data Exchange (ETDEWEB)

    Batista, Evellyne da Silva; Maitelli, Andre Laurindo [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Costa, Rutacio de Oliveira [PETROBRAS S.A., Natal, RN (Brazil). Unidade de Negocio RN/CE; Barbosa, Tiago de Souza [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Engenharia de Computacao

    2008-07-01

    The architecture heterogeneities and petrophysical properties of carbonate reservoirs result from a combination of platform morphology, related depositional environments, relative sea level changes and diagenetic events. The reservoir layering built for static and dynamic modelling purposes should reflect the key heterogeneities (depositional or diagenetic) which govern the fluid flow patterns. The layering needs to be adapted to the goal of the modelling, ranging from full field computations of hydrocarbon volumes, to sector-based fine-scale simulations to test the recovery improvement. This paper illustrates various reservoir layering types, including schemes dominated by depositional architecture, and those more driven by the diagenetic overprint. The examples include carbonate platform reservoirs from different stratigraphic settings (Tertiary, Cretaceous, Jurassic and Permian) and different regions (Europe, Africa and Middle East areas). This review shows how significant stratigraphic surfaces (such as sequence boundaries or maximum flooding) with their associated facies shifts, can be often considered as key markers to constrain the reservoir layering. Conversely, how diagenesis (dolomitization and karst development), resulting in units with particular poroperm characteristics, may significantly overprint the primary reservoir architecture by generating flow units which cross-cut depositional sequences. To demonstrate how diagenetic processes can create reservoir bodies with geometries that cross-cut the depositional fabric, different types of dolomitization and karst development are illustrated. (author)

  19. Shivering heat production and body fat protect the core from cooling during body immersion, but not during head submersion: a structural equation model.

    Science.gov (United States)

    Pretorius, Thea; Lix, Lisa; Giesbrecht, Gordon

    2011-03-01

    Previous studies showed that core cooling rates are similar when only the head or only the body is cooled. Structural equation modeling was used on data from two cold water studies involving body-only, or whole body (including head) cooling. Exposure of both the body and head increased core cooling, while only body cooling elicited shivering. Body fat attenuates shivering and core cooling. It is postulated that this protection occurs mainly during body cooling where fat acts as insulation against cold. This explains why head cooling increases surface heat loss with only 11% while increasing core cooling by 39%. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Jeff's Reef Oculina Banks Clelia Dive 607 2001 Digital Imagery - Captured from Videotapes taken during Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitial imagery, mpegs and jpegs, captured from mini-DV magnetic videotapes collected with an underwater 3-chip CCD color video camera, deployed from the research...

  1. Submersible Aircraft Concept Design Study - Amendment 1. Additional Assessment of Design Risks & Sensitivities within the Original Study, and an Initial Assessment of Key Control Aspects

    Science.gov (United States)

    2011-02-01

    http://www.redhammer.se/tornado/index.html (3) Aircraft Design: A Conceptual Approach, Daniel P. Raymer , AIAA, 1992 (4) (5) Moran, J., Computational...Fluid Dynamics, Wiley & Sons, 1984. Notes on the Stability and Control of Tailless Airplanes, Robert T. Jones, NACA Technical Note No.837, December

  2. histone H3 predominantly mark the pericentromeric chromatin

    Indian Academy of Sciences (India)

    SANTOSH KUMAR SHARMA

    pericentromeric chromatin during mitosis in monokinetic plants. J. Genet. .... bigger), cytological preparations (easy to difficult) as well as their habitat ... Poaceae. Monocot. Land. 14. Triticum aestivum. Common wheat. Poaceae. Monocot. Land.

  3. Sinopsis sobre las Hydrocharitaceae de Colombia

    Directory of Open Access Journals (Sweden)

    Schmidt Mumm Udo

    1996-06-01

    Full Text Available The aquatic family Hydrocharitaceae is actually represented in Colombia by seven genera and seven species (Egeria densa, Apalanthe granatensis, Halophila decipiens, Hydrilla verticillata, Limnobium laevigatum, Thalassia testudinum, Vallisneria americana. A first record of Hydrilla verticillata growing spontaneously in outside conditions is made for this geographical area. A key to genera is presented, with each species briefly commented and illustrated.En Colombia la familia de plantas acuáticas Hydrocharitaceae se encuentra representada por siete géneros y siete especies (Egeria densa, Apalanthe granatensis, Halophila decipiens, Hydrilla verticillata, Limnabium laevigatum, Thalassia testudinum, Vallisneria americana. Para el país se registra por primera vez a Hydrilla verticillata. Adicionalmente se presenta una clave para los géneros, con las especies brevemente comentadas e ilustradas.

  4. Use of Strategic Placement of Dredged Sediments to Support Horseshoe Island in the Atchafalaya River, Louisiana: A Preliminary Ecological Survey

    Science.gov (United States)

    2014-08-01

    cowpea (Vigna luteola), broadleaf cattail (Typha latifolia), invasive Chinese tallowtree (Triadica sebifera), rosemallow (Hibiscus lasiocarpos), and...Benth. hairypod cowpea Fabaceae N Vigna unguiculata (L.) Walp. cowpea Fabaceae - Hydrilla verticillata (L. f.) Royle waterthyme Hydrocharitaceae I

  5. Aquatic Plant Control Research Program

    National Research Council Canada - National Science Library

    Cofrancesco, Alfred

    1998-01-01

    ... (Mydophyllum spice turn) and hydrilla (Hyddlla verticfflata). These species, which account for more that two thirds of all noxious aquatic weed acreage in the United States, have similar characteristics...

  6. Proceedings, Annual Meeting, Aquatic Plant Control Research Program (17th) Held at Sacramento, California on 16-18 November 1982.

    Science.gov (United States)

    1983-06-01

    inhibit the germination of lettuce seeds (Baltrop and Martin 1983). Several observations are pertinent: (1) the effect is concentration dependent; (2) the...formulations of dichlobenil and fluridone were evaluated for control of hydrilla regrowth from rootstocks and from germinating tubers. Hydrilla tubers were...Carriers for Controlled Release of Fluridone -R. L. Dunn, Southern Research Institute Birmingham, Alabama 10:55 a.m. Herbicide Evaluation Program -T. K. Van

  7. A Survey of the Invasive Aquatic and Riparian Plants of the Lower Rio Grande

    Science.gov (United States)

    2005-04-01

    monocultures in many areas. In 2001 and 2003, surveys were conducted starting below Amistad Reservoir to immediately below Falcon Reservoir to assess...management programs to inhibit further new infestations locally and downstream. In 2001, 20 sites on the Rio Grande River were surveyed from Amistad Reservoir...the 2001 survey, hydrilla was found in Amistad Reservoir and below Falcon Reservoir. In August 2002, hydrilla fragments were observed in plant

  8. A Survey of the Invasive Aquatic and Riparian Plants of the Low Rio Grande

    Science.gov (United States)

    2005-04-01

    many areas. In 2001 and 2003, surveys were conducted starting below Amistad Reservoir to immediately below Falcon Reservoir to assess the...River were surveyed from Amistad Reservoir to Anzulduas Dam for the presence of hydrilla and other invasive aquatic weed species (Grodowitz et al...to difficulties in accessing the river. During the 2001 survey, hydrilla was found in Amistad Reservoir and below Falcon Reservoir. In August 2002

  9. Application of Elovich equation on uptake kinetics of 137Cs by living freshwater macrophytes - a short duration laboratory study

    International Nuclear Information System (INIS)

    Jaison, T.J.; Patra, A.K.; Ravi, P.M.; Tripathi, R.M.

    2014-01-01

    Application of Elovich equation on uptake kinetics of 137 Cs by two living macrophytes during controlled experiments on short duration exposure is studied. Compliance to 2 nd order kinetics indicates the mechanism could be chemi-sorption, involving polar functional groups present on the extracelluar surface of the macrophytes. Data analysis suggests that Myriophyllum s. exhibits faster adsorption rate than Hydrilla v. As Myriophyllum s. exhibits better kinetics than Hydrilla v., former could be a better natural adsorbing media for 137 Cs. (author)

  10. Okeanos Explorer (EX1404L2): Our Deepwater Backyard: Exploring the Atlantic Canyons and Seamounts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — High resolution mapping data from vessel multibeam and submersible sonar systems; singlebeam and sub-bottom profile data; periodic CTD casts; submersible CTD data;...

  11. Okeanos Explorer (EX1404L3): Northeast Seamounts and Canyons

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — High resolution mapping data from vessel multibeam and submersible sonar systems; singlebeam and sub-botoom profile data; periodic CTD casts; submersible CTD data;...

  12. Evaluation of butachlor for control of some submerged macrophytes along with its impact on biotic components of freshwater system

    Directory of Open Access Journals (Sweden)

    A. Chattopadhyay, S. Adhikari, S. P. Adhikary, S. Ayyappan

    2006-04-01

    Full Text Available In this investigation, the efficacy of the herbicide butachlor, (N-butoxymethyl-2 chloro-21, 61 diethyl acetanilide was tested against few common submerged macrophytes namely Hydrilla (Hydrilla verticillata (L. Royale, Najas (Najas minor All., Nechamandra (Nechamandra alternifolia (Roxb. Thwaites and Ottelia (Ottelia alismoides (L. Pers. of freshwater fish ponds. Almost complete decay of Hydrilla, Nechamandra and Ottelia was achieved at 7.5 L of active ingredient/ha/m butachlor within 15 days while the herbicide showed no negative effect on Najas. However at the same concentration of butachlor, total mortality of zooplankton and water fern Azolla (Azolla caroliniana Lamarck occurred within seven days. In case of few freshwater fish species like Rohu (Labeo rohita, Channa (Channa punctatus, Anabas (Anabas testitudineus and Heteropneustes (Heteropneustes fossilis, total mortality occurred upto 90 days after application of the same dose of butachlor but fish survived beyond 120 days of herbicide application indicating degradation of the herbicides.

  13. MEMPELAJARI FISIOLOGI PENCEMARAN LINGKUNGAN DENGAN TEHNIK RADIOISOTOP (Study in the Physiology of Environment Pollution Using Radiotracer Method

    Directory of Open Access Journals (Sweden)

    Razak Achmad Hamzah

    2011-11-01

    Full Text Available ABSTRAK Penelitian ini bertujuan untuk mengetahui: 1. Perbedaan kemampuan daya serap tumbuhan air Hydrilla verticillata, Enceng gondok (Eichhomia crassipes dan Kangkung terhadap residu Malathion, menggunakan akuarium (diisi dengan air + Hydrilla Verticillata + Enceng Gondok + Kangkung + Malathion radioisotope 14C. 2. Perbandingan kadar malathion dalam jaringan ikan yang mendapat makanan Hydrilla verticilata dengan yang mendapat makanan kangkung, menggunakan: (akuarium pertama diisi air + Hydrilla Vericillata + ikan mas + Malathion radioisotope 14C; akuarium ke dua diisi air + kangkung + ikan mas + malathion radiisotop 14C. 3. Perbandingan ukuran penyerapan pada jaringan mammalia (tikus yang diberi makan jaringan ikan mas dengan yang diberi makan tumbuhan air (kangkung yang terkontaminasi. Jaringan ikan mas dan kangkung dilakukan pengabuan basah, lalu diberikan masing-masing kepada 30 ekor tikus. Kadar Malathion dari semua percobaan satu, dua dan tiga, diketahui dengan menggunakan alat pencacah Sintilator cair (Liquid Scintillation Spectrometer, LSC- 753 (ALOKA”. Hasil yang didapat dibandingkan dengan menggunakan uji-t Student. Hasil penelitian memperlihatkan bahwa: 1. Hydrilla Verticillata lebih efisien dari pada Enceng Gondok dan Kangkung dalam menyerap residu insektisida malathion dalam air. 2. Ikan yang diberi makan Hydrilla verticillata mengkonsentrasikan malathion lebih tinggi dari pada ikan yang diberi makan kangkung. 3. Mammalia (tikus yang mengkonsumsi daging ikan yang terkontaminasi akan mengkonsentrasikan malathion dalam tubuhnya lebih banyak dari pada tikus yang memakan sayuran (kangkung yang terkontaminasi. ABSTRACT The aim of this study is to determine: 1.The comparison of absorption by aquatic plants Hydrilla verticillata, water hyacinth and water spinach of Malathion insecticide residues in water, (aquarium filled with water + Hydrilla verticillata + water hyacinth + water spinach + 20 mci 14C malathion radioisotope; 2

  14. Digital Video taken during Johnson-Sea-Link submersible dive 4922 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 18, 2005 (NCEI Accession 0036658)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These video data were recorded during the Florida Coast Deep Corals mission of 2005. Data gathered during this expedition provide a strong foundation of information...

  15. Digital Video taken during Johnson-Sea-Link submersible dive 4916 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 11, 2005 (NCEI Accession 0036986)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These video data were recorded during the Florida Coast Deep Corals mission of 2005. Data gathered during this expedition provide a strong foundation of information...

  16. Digital Video taken during the 3-person submersible Clelia dive 613 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, September 01, 2001 (NCEI Accession 0037126)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The video data in this accession was captured during the Islands in the Stream mission of 2001. Islands in the Stream was a three-month scientific expedition to...

  17. SEACAT CTD data of the Hawaii Undersea Research Program from 593 dives of the remotely operated vehicle and the submersibles Pisces IV and V during 1995-2012 in the North and South Pacific (NODC Accession 0116373)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Hawaii Undersea Research Laboratory (HURL) was established by the National Oceanic and Atmospheric Administration (NOAA) and the University of Hawaii. Its...

  18. South Experimental Oculina Research Reserve, Clelia Dive 610 2001 Digital Imagery - Captured from Videotapes taken during Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitial imagery, mpegs and jpegs, captured from mini-DV magnetic videotapes collected with an underwater 3-chip CCD color video camera, deployed from the research...

  19. Digital Video taken during the 3-person submersible Clelia dive 608 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, August 30, 2001 (NCEI Accession 0039353)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  20. Central Experimental Oculina Research Reserve, Clelia Dive 612 2001 Digital Imagery - Captured from Videotapes taken during Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digitial imagery, mpegs and jpegs, captured from mini-DV magnetic videotapes collected with an underwater 3-chip CCD color video camera, deployed from the research...

  1. Digital Video taken during the 3-person submersible Clelia dive 607 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, August 29, 2001 (NCEI Accession 0039467)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  2. Digital Video taken during the 3-person submersible Clelia dive 612 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, September 01, 2001 (NCEI Accession 0037156)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  3. Digital Video taken during the 3-person submersible Clelia dive 610 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, August 31, 2001 (NCEI Accession 0037158)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The video data in this accession was captured during the Islands in the Stream mission of 2001. Islands in the Stream was a three-month scientific expedition to...

  4. Digital Video taken during the 3-person submersible Clelia dive 611 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, August 31, 2001 (NCEI Accession 0037157)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  5. Digital Video taken during the 3-person submersible Clelia dive 618 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, September 04, 2001 (NCEI Accession 0041700)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  6. Digital Video taken during the 3-person submersible Clelia dive 620 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, September 05, 2001 (NCEI Accession 0041969)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  7. Digital Video taken during the 3-person submersible Clelia dive 616 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, September 03, 2001 (NCEI Accession 0041480)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  8. Digital Video taken during the 3-person submersible Clelia dive 615 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, September 02, 2001 (NCEI Accession 0041370)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  9. Digital Video taken during the 3-person submersible Clelia dive 622 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, September 07, 2001 (NCEI Accession 0039430)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  10. Digital Video taken during the 3-person submersible Clelia dive 609 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, August 30, 2001 (NCEI Accession 0037122)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The video data in this accession was captured during the Islands in the Stream mission of 2001. Islands in the Stream was a three-month scientific expedition to...

  11. Digital Video taken during the 3-person submersible Clelia dive 621 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, September 05, 2001 (NCEI Accession 0039428)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  12. Digital Video taken during the 3-person submersible Clelia dive 614 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, September 02, 2001 (NCEI Accession 0039974)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  13. Digital Video taken during the 3-person submersible Clelia dive 617 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, September 03, 2001 (NCEI Accession 0041593)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  14. Digital video taken during the 3-person submersible Clelia dive 606 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, August 29, 2001 (NCEI Accession 0039739)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The video data in this accession was captured during the Islands in the Stream mission of 2001. Islands in the Stream was a three-month scientific expedition to...

  15. Toxicological Risk Assessment of a Nickel Compound Found on the Surfaces of Replacement Hyperstretch Neoprene (CWU-83P) Neck and Wrist Seals for a Cold water Submersion Survival Suit

    National Research Council Canada - National Science Library

    Arfsten, Darryl

    2001-01-01

    .... The conservative approach for estimating the toxicological risk of nickeldialkyldithiocarbamate exposure to humans is to assume that these compounds have the same toxic properties as soluble nickel compounds. Lifetime average daily dose (LADD) estimates for persons wearing cold water survival suits were calculated using conservative exposure assumptions.

  16. 1998 Annual Status Report: Status and Trend of Submersed and Floating-leaved Aquatic Vegetation in Thirty-two Backwaters in Pools 4, 8, 13, and 26 and La Grange Pool of the Upper Mississippi River System

    National Research Council Canada - National Science Library

    Yin, Yao

    2000-01-01

    .... The status and trend of aquatic vegetation in 1998 varied among the thirty-two backwaters. In upper Pool 4 (above Lake Pepin), where aquatic vegetation has declined since 1991, the trend continued in 1998...

  17. Digital Video taken during Johnson-Sea-Link submersible dive 4918 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 16, 2005 (NCEI Accession 0036895)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This video data was recorded during the Florida Coast Deep Corals mission of 2005. The data gathered during this expedition provided a strong foundation of...

  18. Digital Video taken during Johnson-Sea-Link submersible dive 4919 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 17, 2005 (NCEI Accession 0036826)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This video data was recorded during the Florida Coast Deep Corals mission of 2005. The data gathered during this expedition provided a strong foundation of...

  19. Digital Video taken during Johnson-Sea-Link submersible dive 4920 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 17, 2005 (NCEI Accession 0036825)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This video data was recorded during the Florida Coast Deep Corals mission of 2005. The data gathered during this expedition provided a strong foundation of...

  20. Digital Video taken during Johnson-Sea-Link submersible dive 4914 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 10, 2005 (NCEI Accession 0037043)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This video data was recorded during the Florida Coast Deep Corals mission of 2005. The data gathered during this expedition provided a strong foundation of...

  1. Digital Video taken during Johnson-Sea-Link submersible dive 4921 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 18, 2005 (NCEI Accession 0036824)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This video data was recorded during the Florida Coast Deep Corals mission of 2005. The data gathered during this expedition provided a strong foundation of...

  2. Digital Video taken during Johnson-Sea-Link submersible dive 4911 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 09, 2005 (NCEI Accession 0036985)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This video data was recorded during the Florida Coast Deep Corals mission of 2005. The data gathered during this expedition provided a strong foundation of...

  3. Digital Video taken during Johnson-Sea-Link submersible dive 4909 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 08, 2005 (NCEI Accession 0036667)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This video data was recorded during the Florida Coast Deep Corals mission of 2005. The data gathered during this expedition provided a strong foundation of...

  4. Digital Video taken during Johnson-Sea-Link submersible dive 4913 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 10, 2005 (NCEI Accession 0037065)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This video data was recorded during the Florida Coast Deep Corals mission of 2005. The data gathered during this expedition provided a strong foundation of...

  5. Digital Video taken during Johnson-Sea-Link submersible dive 4917 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 16, 2005 (NCEI Accession 0036972)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This video data was recorded during the Florida Coast Deep Corals mission of 2005. The data gathered during this expedition provided a strong foundation of...

  6. Digital Video taken during Johnson-Sea-Link submersible dive 4912 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 09, 2005 (NCEI Accession 0037102)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This video data was recorded during the Florida Coast Deep Corals mission of 2005. The data gathered during this expedition provided a strong foundation of...

  7. Digital Video taken during Johnson-Sea-Link submersible dive 4910 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 08, 2005 (NCEI Accession 0036668)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This video data was recorded during the Florida Coast Deep Corals mission of 2005. The data gathered during this expedition provided a strong foundation of...

  8. Digital Video taken during Johnson-Sea-Link submersible dive 4915 of the NOAA Office of Ocean Exploration's Florida Coast Deep Corals 2005 cruise, November 11, 2005 (NCEI Accession 0037022)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This video data was recorded during the Florida Coast Deep Corals mission of 2005. The data gathered during this expedition provided a strong foundation of...

  9. Digital video collected during Pisces II submersible dive 880018 by Bureau of Ocean Energy Management (BOEM) in the Gulf of Mexico on 1988-07-28 (NCEI Accession 0164789)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This Archival Information Package (AIP) contains videographic data of ocean floor biology and geology at a suspected hydrocarbon seep site in the Gulf of Mexico,...

  10. Proceedings of the Undersea Medical Society Workshop (7th) on Medical Aspects of Small Submersible Operations Held at Submarine Development Group 1, San Diego, California on 19-20 November 1974

    Science.gov (United States)

    1975-01-01

    with approximately 3000 lb pull. Menzie, and Meek were assisted from the forward compartment and given pre- 11-21 cautionary recompression therapy . The...UG-36 floatation foam inside a polyethelene tube. This helps avoid entanglement of the FISH and aids maneuverability. Although the multiplex cable

  11. Digital Video taken during the 3-person submersible Clelia dive 619 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, September 04, 2001 (NCEI Accession 0041848)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  12. Resonance – Journal of Science Education | Indian Academy of ...

    Indian Academy of Sciences (India)

    https://www.ias.ac.in/article/fulltext/reso/018/02/0156-0162. Keywords. Hydrilla verticillata; keystone species; invasive weeds; carbon sequestration; bioremediation; AVM disease. Author Affiliations. Stephen Sumithran1 P J Sanjeeva Raj. Department of Biological Sciences, Eastern Kentucky University Richmond, KY. 40475 ...

  13. P J Sanjeeva Raj

    Indian Academy of Sciences (India)

    Volume 13 Issue 7 July 2008 pp 648-654 General Article. Oysters in a New Classification of Keystone Species · P J Sanjeeva Raj · More Details Fulltext PDF. Volume 18 Issue 2 February 2013 pp 156-162 General Article. Keystone Functions of Hydrilla verticilata · Stephen Sumithran P J Sanjeeva Raj · More Details Fulltext ...

  14. Decomposition characteristics of three different kinds of aquatic macrophytes and their potential application as carbon resource in constructed wetland.

    Science.gov (United States)

    Wu, Suqing; He, Shengbing; Zhou, Weili; Gu, Jianya; Huang, Jungchen; Gao, Lei; Zhang, Xu

    2017-12-01

    Decomposition of aquatic macrophytes usually generates significant influence on aquatic environment. Study on the aquatic macrophytes decomposition may help reusing the aquatic macrophytes litters, as well as controlling the water pollution caused by the decomposition process. This study verified that the decomposition processes of three different kinds of aquatic macrophytes (water hyacinth, hydrilla and cattail) could exert significant influences on water quality of the receiving water, including the change extent of pH, dissolved oxygen (DO), the contents of carbon, nitrogen and phosphorus, etc. The influence of decomposition on water quality and the concentrations of the released chemical materials both followed the order of water hyacinth > hydrilla > cattail. Greater influence was obtained with higher dosage of plant litter addition. The influence also varied with sediment addition. Moreover, nitrogen released from the decomposition of water hyacinth and hydrilla were mainly NH 3 -N and organic nitrogen while those from cattail litter included organic nitrogen and NO 3 - -N. After the decomposition, the average carbon to nitrogen ratio (C/N) in the receiving water was about 2.6 (water hyacinth), 5.3 (hydrilla) and 20.3 (cattail). Therefore, cattail litter might be a potential plant carbon source for denitrification in ecological system of a constructed wetland. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Use of phosphorus to alleviate stress induced by cadmium and zinc ...

    African Journals Online (AJOL)

    The potential mechanism by which P antagonizes the toxicity of Zn and Cd was investigated in Elodea nuttallii and Hydrilla verticillata to understand the interactions between P, Cd and Zn pollutants. The two submerged macrophytes were treated with a combination of Cd (0.25 mg L-1) and Zn (1.0 mg L-1) and various ...

  16. Final Environmental Assessment Implementation of the Integrated Natural Resources Management Plan for Avon Park Air Force Range Florida

    Science.gov (United States)

    2004-01-01

    divine nightshade (Solanum nigrescens) Coast sandspur (Cenchrus incertus) Three plants — tropical soda apple (Solanum viarum), cogon grass ( Imperata ...consequence on the APAFR ecosystem. However in the last 5 years, there has been an increase in the number of sites where cogon grass ( Imperata ...verticillata Hydrilla Hymenachne amplexicaulis West In mdian arsh grass Imperata cylindrica Cogon grass Lantana camara Lantana Ligustrum sinense Chinese

  17. The Geology of Burma (Myanmar): An Annotated Bibliography of Burma’s Geology, Geography and Earth Science

    Science.gov (United States)

    2008-09-01

    Eichornia-Crassipes; Ephydatia-Fluviatilis; Hydrilla; Imperata ; Inle; Intha; Shan; Utricularia. Abstract: cultural data on the people and a bibliography...characterized by dipterocarpus Bibliography of Burman Earth Science September 2008 71 tuberculatus and associated plants; the other by imperata . The

  18. Hydrothermal processing of biomass from invasive aquatic plants

    Science.gov (United States)

    W. James Catallo; Todd F. Shupe; Thomas L. Eberhardt

    2008-01-01

    The purpose of this study was to examine the hydrothermal (HT) treatment of three invasive aquatic plants (i.e., Lemna sp., Hydrilla sp., and Eichhornia sp.) with respect to the generation of semi-volatile hydrocarbon product mixtures and biomass volume reduction. Identical HT treatments yielded similar semi-...

  19. Investigation of Processes and Factors Regulating the Generation, Maintenance and Breakdown of Bioluminescent Thin Layers

    National Research Council Canada - National Science Library

    Widder, Edith

    2001-01-01

    .... Katz's submersible holographic camera mounted on the upper work platform. Thin layers were located using real-time sensor feedback from intensified video recordings of stimulated bioluminescence...

  20. Assessing Hydraulic Modifications on Vallisneria americana in Peoria Lake, Illinois. A Pilot Study Using Data Sharing Protocols to Integrate Legacy Models

    National Research Council Canada - National Science Library

    Black, Patrick

    2003-01-01

    .... The modeling was directed toward an investigation of potential population increase of the submersed macrophyte Vallisneila americana as a consequence of the construction of a hypothetical levee...

  1. Wheat streak mosaic virus coat protein is a host-specific long-distance transport determinant in oat

    Science.gov (United States)

    Viral determinants involved in systemic infection of hosts by monocot-infecting plant viruses are poorly understood. Wheat streak mosaic virus (WSMV, genus Tritimovirus, family Potyviridae) exclusively infects monocotyledonous crops such as wheat, oat, barley, maize, triticale, and rye. Previously, ...

  2. Is there evidence of optimisation for carbon efficiency in plant proteomes?

    KAUST Repository

    Jankovic, Boris R.; Seoighe, Cathal; Alquraishi, May Majed; Gehring, Christoph A

    2011-01-01

    Flowering plants, angiosperms, can be divided into two major clades, monocots and dicots, and while differences in amino acid composition in different species from the two clades have been reported, a systematic analysis of amino acid content

  3. Transfer of the Ecuadorian species Oncidium hernandezii to the genus Caucaea (Orchidaceae)

    Czech Academy of Sciences Publication Activity Database

    Kolanowska, Marta; Hirtz, A.; Tobar Suarez, D. F.

    2017-01-01

    Roč. 309, č. 3 (2017), s. 299-299 ISSN 1179-3155 Institutional support: RVO:86652079 Keywords : Caucaea * new combination * Monocots Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 1.240, year: 2016

  4. Effect of various amino acids on shoot regeneration of sugarcane ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-04-06

    Apr 6, 2009 ... Full Length Research Paper. Effect of various amino acids .... maize, sorghum, pineapple, rice and other monocots to enhance somatic ... without additional amino acids, making a total of 26 treatments. All culture media were ...

  5. Identification and validation of a virus-inducible ta-siRNA-generating ...

    Indian Academy of Sciences (India)

    2016-02-01

    Feb 1, 2016 ... and bacterial spot disease resistance protein Bs4 gene. ... whitefly (Bemisia tabaci) and infect a variety of crops, both monocot and dicot, causing ..... virus variant associated with newly emerging yellow mosaic disease of ...

  6. Paper on Arsenic

    African Journals Online (AJOL)

    Hiren

    The current study was undertaken to determine the effects of arsenic on ... concentration caused reduction in plant growth along with induction of few antioxidants. ... esculentum, a herbaceous monocot plant, towards reactive oxygen species.

  7. Hostplant change and paleoclimatic events explain diversification shifts in skipper butterflies (Family: Hesperiidae).

    Science.gov (United States)

    Sahoo, Ranjit Kumar; Warren, Andrew D; Collins, Steve C; Kodandaramaiah, Ullasa

    2017-08-02

    Skippers (Family: Hesperiidae) are a large group of butterflies with ca. 4000 species under 567 genera. The lack of a time-calibrated higher-level phylogeny of the group has precluded understanding of its evolutionary past. We here use a 10-gene dataset to reconstruct the most comprehensive time-calibrated phylogeny of the group, and explore factors that affected the diversification of these butterflies. Ancestral state reconstructions show that the early hesperiid lineages utilized dicots as larval hostplants. The ability to feed on monocots evolved once at the K-Pg boundary (ca. 65 million years ago (Mya)), and allowed monocot-feeders to diversify much faster on average than dicot-feeders. The increased diversification rate of the monocot-feeding clade is specifically attributed to rate shifts in two of its descendant lineages. The first rate shift, a four-fold increase compared to background rates, happened ca. 50 Mya, soon after the Paleocene-Eocene thermal maximum, in a lineage of the subfamily Hesperiinae that mostly fed on forest monocots. The second rate shift happened ca. 40 Mya in a grass-feeding lineage of Hesperiinae when open-habitat grasslands appeared in the Neotropics owing to gradual cooling of the atmospheric temperature. The evolution of monocot feeding strongly influenced diversification of skippers. We hypothesize that although monocot feeding was an intrinsic trait that allowed exploration of novel niches, the lack of extensive availability of monocots comprised an extrinsic limitation for niche exploration. The shifts in diversification rate coincided with paleoclimatic events during which grasses and forest monocots were diversified.

  8. The Phytotoxicity of Designated Pollutants

    Science.gov (United States)

    1981-12-01

    for specific reasons including horticultural type, ease of growth, and physical characteristics such as size, shape, and number of leaves. Both monocots... horticultural types from monocots to dicots and from field crops and ornamentals to garden varieties. The seeds, either soaked for two hours in DDW or wetted...than older plants. REFERENCES Albert, A., 1979, Selective toxicity, the physico-chemical basis of therapy , John Wiley & Sons, New York, 6th ed., 662

  9. Monitoring Invasive Aquatic Vegetation in Lake Okeechobee, Florida, Using NDVI Derived from Modis Data

    Science.gov (United States)

    Woods, Kate; Brozen, Madeline; Malik, Sadaf; Maki, Angela

    2009-01-01

    Lake Okeechobee, located in southern Florida, encompasses approximately 1,700 sq km and is a vital part of the Lake Okeechobee and Everglades ecosystem. Major cyanobacterial blooms have been documented in Lake Okeechobee since the 1970s and have continued to plague the ecosystem. Similarly, hydrilla, water hyacinth, and water lettuce have been documented in the lake and continue to threaten the ecosystem by their rapid growth. This study examines invasive aquatic vegetation occurrence through the use of the Normalized Difference Vegetation Index (NDVI) calculated on MOD09 surface reflectance imagery. Occurrence during 2008 was analyzed using the Time Series Product Tool (TSPT), a MATLAB-based program developed at John C. Stennis Space Center. This project tracked spatial and temporal variability of cyanobacterial blooms, and overgrowth of water lettuce, water hyacinth, and hydrilla. In addition, this study presents an application of Moderate Resolution Imaging Spectroradiometer (MODIS) data to assist in water quality management.

  10. Is there evidence of optimisation for carbon efficiency in plant proteomes?

    KAUST Repository

    Jankovic, Boris R.

    2011-07-25

    Flowering plants, angiosperms, can be divided into two major clades, monocots and dicots, and while differences in amino acid composition in different species from the two clades have been reported, a systematic analysis of amino acid content and distribution remains outstanding. Here, we show that monocot and dicot proteins have developed distinct amino acid content. In Arabidopsis thaliana and poplar, as in the ancestral moss Physcomitrella patens, the average mass per amino acid appears to be independent of protein length, while in the monocots rice, maize and sorghum, shorter proteins tend to be made of lighter amino acids. An examination of the elemental content of these proteomes reveals that the difference between monocot and dicot proteins can be largely attributed to their different carbon signatures. In monocots, the shorter proteins, which comprise the majority of all proteins, are made of amino acids with less carbon, while the nitrogen content is unchanged in both monocots and dicots. We hypothesise that this signature could be the result of carbon use and energy optimisation in fast-growing annual Poaceae (grasses). © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

  11. The Pattern and Frequency of Drowning Autopsies in Benin City ...

    African Journals Online (AJOL)

    Introduction: Drowning is a form of violent asphyxia death, where in the entry of air into the lungs, is prevented by water or other fluids due to the submersion of mouth and nostril (complex submersion of whole body is not necessary). Aim and objective: To determine profile/patterns of all drowning autopsies in our ...

  12. Utility of Army Design Methodology in U.S. Coast Guard Counter Narcotic Interdiction Strategy

    Science.gov (United States)

    2017-06-09

    including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations...or functionality of the strategy itself. It is important to note, the interrogative process of FAS generally takes place after risk has been evaluated...confiscated 52 these fully submersible vessels in mid construction, however credible data suggests fully submersible vessels are in operation and

  13. 78 FR 36598 - Petitions for Modification of Application of Existing Mandatory Safety Standards

    Science.gov (United States)

    2013-06-18

    ... and grout seal isolate the completed blind drilled shaft from any coal seams mitigating any..., three-phase, alternating current submersible pump, to dewater completed ventilation shafts prior to... prior to construction via the required shaft plan for any blind drilled shaft when any submersible pump...

  14. 75 FR 9207 - Notice of a Project Waiver of Section 1605 (Buy American Requirement) of the American Recovery...

    Science.gov (United States)

    2010-03-01

    ... the purchase of a GrundFos SQ Flex 6 SQF- 2 solar powered submersible pump system with control and solar panels (pump system) manufactured in Denmark by GrundFos. This is a project specific waiver and... powered submersible pump system with control and solar panels (pump system) manufactured in Denmark by...

  15. Applying the 'general principles of dose calculation' (ABG) in practice. Pt. 1

    International Nuclear Information System (INIS)

    Haubelt, R.

    1985-01-01

    Radiation doses are to be calculated for the main exposure pathways such as gamma submersion, beta submersion, gamma radiation at ground level, inhalation and ingestion of radionuclides. After the amendment of the German Radiation Protection Ordinance to include the latest ICRP Recommendations, the dose to be determined now is the effective dose equivalent, replacing the former whole-body dose equivalent. (DG) [de

  16. Environmental Factors Influencing Blooms of a Neurotoxic Stigonematalan Cyanobacterium Responsible for Avian Vacuolar Myelinopathy

    Science.gov (United States)

    2013-01-01

    models provide insights into predicting the seasonal prevalence of Stigonematales in reservoirs. The findings in this technical note suggest that...cultures contained elevated levels of BMAA (Bidigare et al. 2009). There is still no evidence that mammals can contract AVM. Beavers (Castor...discovered in JSTL in 1994, is the most prevalent SAV species. Prior to the introduction of hydrilla, the lake did not support a substantial community

  17. Akkumulation von L-Malat und D-Lactat in Arabidopsis thaliana und Laccase/HBT-vermittelte Delignifizierung von Spartina alterniflora und Phragmites australis

    OpenAIRE

    Heil, Alexander

    2016-01-01

    The current work contains two projects "Accumulation of L-malate and D-lactate in Arabidopsis thaliana" (A) "Laccase/HBT mediated delignification of Spartina alterniflora and Phragmites australis" (B). In project A, L-malate and D-lactate accumulated in A. thaliana plants. The accumulation of L-malate is carried out by modification of the plant metabolism with the enzymes PEPC, MDH and the tonoplast dicarboxylate transporter (TDT). Gene pepci2 (Hydrilla verticillata), mdh5 (Zea mays) and tdt ...

  18. ALTERNATE FOOD-CHAIN TRANSFER OF THE TOXIN LINKED TO AVIAN VACUOLAR MYELINOPATHY AND IMPLICATIONS FOR THE ENDANGERED FLORIDA SNAIL KITE (ROSTRHAMUS SOCIABILIS).

    Science.gov (United States)

    Dodd, Shelley R; Haynie, Rebecca S; Williams, Susan M; Wilde, Susan B

    2016-04-28

    Avian vacuolar myelinopathy (AVM) is a neurologic disease causing recurrent mortality of Bald Eagles ( Haliaeetus leucocephalus ) and American Coots ( Fulica americana ) at reservoirs and small impoundments in the southern US. Since 1994, AVM is considered the cause of death for over 170 Bald Eagles and thousands of American Coots and other species of wild birds. Previous studies link the disease to an uncharacterized toxin produced by a recently described cyanobacterium, Aetokthonos hydrillicola gen. et sp. nov. that grows epiphytically on submerged aquatic vegetation (SAV). The toxin accumulates, likely in the gastrointestinal tract of waterbirds that consume SAV, and birds of prey are exposed when feeding on the moribund waterbirds. Aetokthonos hydrillicola has been identified in all reservoirs where AVM deaths have occurred and was identified growing abundantly on an exotic SAV hydrilla ( Hydrilla verticillata ) in Lake Tohopekaliga (Toho) in central Florida. Toho supports a breeding population of a federally endangered raptor, the Florida Snail Kite ( Rostrhamus sociabilis ) and a dense infestation of an exotic herbivorous aquatic snail, the island applesnail ( Pomacea maculata ), a primary source of food for resident Snail Kites. We investigated the potential for transmission in a new food chain and, in laboratory feeding trials, confirmed that the AVM toxin was present in the hydrilla/A. hydrillicola matrix collected from Toho. Additionally, laboratory birds that were fed apple snails feeding on hydrilla/A. hydrillicola material from a confirmed AVM site displayed clinical signs (3/5), and all five developed brain lesions unique to AVM. This documentation of AVM toxin in central Florida and the demonstration of AVM toxin transfer through invertebrates indicate a significant risk to the already diminished population of endangered Snail Kites.

  19. Species and biogeochemical cycles of organic phosphorus in sediments from a river with different aquatic plants located in Huaihe River Watershed, China.

    Science.gov (United States)

    Yuan, He Zhong; Pan, Wei; Ren, Li Jun; Liu, Eeng Feng; Shen, Ji; Geng, Qi Fang; An, Shu Qing

    2015-01-01

    The results of phosphorus fractionation in the sediments from a contaminated river containing different aquatic plants, analyzed by solution 31P-NMR for Organic Phosphorus, showed that the concentration of Inorganic Phosphorus dominated in all species and Organic Phosphorus accounted for over 20% of Total Phosphorus. In general, orthophosphate was dominant in all the sampling sites. The proportion of Organic Phosphorus accounting for the Total Phosphorus in the sediments with different plant decreased in the following order: Paspalum distichum>Typha orientalis>Hydrilla verticillata. Phosphorus-accumulation ability of Paspalum distichum was obviously stronger than Typha orientalis and Hydrilla verticillata. The Organic Phosphorus was in aquatic plants dominated by humic-associated P (Hu-P), which converted to Inorganic Ohosphorus more significantly in submerged plants than in emerged plants. The sediment dominated by Paspalum distichum abundantly accumulated Organic Phosphorus in the orthophosphate monoester fraction. The degradation and mineralization of orthophosphate monoester was the important source of high Inorganic Phosphorus concentration and net primary productivity in Suoxu River. The Organic Phosphorus derived from Typha orientalis and Hydrilla verticillata was dramatically converted to Inorganic Phosphorus when the environmental factors varied.

  20. Ash characteristics and plant nutrients in some aquatic biomasses

    Science.gov (United States)

    Masto, Reginald; Pandit, Ankita; George, Joshy; Mukhopadhyay, Sangeeta; Selvi, Vetrivel; Ram, Lal

    2016-04-01

    Aquatic biomasses are explored as potential fuel source for direct combustion because of their faster growth and no land requirement. The energy density and the ash characteristics of the aquatic biomasses are to be evaluated for their suitability for energy extraction. In the study, four aquatic plant samples namely Eichornia crassipes, Hydrilla verticilleta, Lemna minor, Spirogyra spp were collected from a pond in Digwadih Campus of Central Institute of Mining and Fuel Research, Dhanbad. The biomasses were air dried, powdered and ashed at different temperatures. Volatile C was relatively lower in Spirogyra and Hydrilla (53 %) than Eichornia (62.6 %) or Lemna (59.7 %), whereas fixed C was higher for Eichornia and Lemna (about 10 %) and lower for Hydrilla (1 %). Ultimate analysis showed that the carbon content was in the order Eichornia > Lemna > Spirogyra > Hydrilla. The IR spectra of each raw biomass is compared to their respective ashes obtained at different temperatures (500-900°C). With increase in ashing temperature from 500-900°C there is gradual breakdown of the cellulosic structure hence, peaks around 2900-2800cm-1 caused by aliphatic C-H vibration tends to disappear slowly in ash. More number of peaks appears at lower wavenumbers in ashes of all the biomass samples indicating towards increased percentage of inorganic ion species. Considerable enrichment of SiO2 is validated with prominent peaks at 1100-900 cm-1 in all the ashes. Lemna and Spirogyra has a similar ash composition (Si > Al > Ca > K), whereas, Ca was higher in Hydrilla (Si > Ca > K > Al). Eichornia (Si > K > Ca > Al) has higher K and Ca than Al. SiO2 and Al2O3 were higher in Spirogyra, while SiO2 and CaO in Eichornia and Hydrilla. K first increased from 500-700/800⁰C, and then decreased from 800-900⁰C. Cl is lost slowly in ash from 500-700/800⁰C and then by a drastic reduction from 800-900⁰C. S is enhanced in ash at all temperatures although the change is quite small. Most of the Cl

  1. Early remote laser detection of vegetation damage caused by certain environmental stress factors

    Science.gov (United States)

    Chappelle, Emmett W.; Mcmurtrey, James E., III

    1989-01-01

    The fluorescence spectra of plants excited with a pulsed nitrogen laser beam emitting at 337 nm were found to be related to plant type, as well as with changes in the physiology of the plant as the result of various kinds of environmental stress. The plant types which were studied included herbaceous dicots, monocots, hardwoods, and conifers. These plant types could be identified on the basis of differences in either the number of fluorescent bands, or the relative intensity of the bands. The dicots and monocots had fluorescent maxima at 440, 685, and 740 nm. The monocots could be distinguished from the dicots by virtue of having a much higher 440 nm/685 nm ratio. Hardwoods and conifers had an additional fluorescence band at 525 nm, but healthy conifers did not have a band at 685 nm.

  2. EOP Gold Coral (Gerardia sp.) Growth Measurements

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gold coral (Gerardia sp.) trees that were inspected years earlier on Pisces submersible dives were revisited and their change in size measured. The fishery for...

  3. Exploring Alaska's Seamounts on RV Atlantis in North Pacific Ocean and Gulf of Alaska between 20040730 and 20040823

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Five seamounts (Denson, Dickins, Pratt, Welker and Giacomini) in the Gulf of Alaska that had not previously been observed by manned submersible or ROV were...

  4. Oceanographic data collected during the Expedition to the Deep Slope 2007 aboard NOAA Ship Ronald H. Brown in Northern Gulf of Mexico Continental Slope from 2007-06-03 to 2007-07-06 (NCEI Accession 0053265)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Expedition produced 600 DVDs of video recorded from a Science Camera, a Brow Camera and a Pilot's Camera from the JASON submersible; a video annotations log...

  5. 78 FR 61873 - Revisions to the Export Administration Regulations (EAR) To Make the Commerce Control List (CCL...

    Science.gov (United States)

    2013-10-04

    ... entitled Revisions to the Export Administration Regulations: Military Vehicles; Vessels of War; Submersible...'' references by this rule will require exporters to spend substantially more time to determine the scope of the...

  6. REMOTE BIOSENSOR FOR IN SITU MONITORING OF ORGANOPHOSPHATE NERVE AGENTS. (R823663)

    Science.gov (United States)

    A remote electrochemical biosensor for field monitoring of organophosphate nerve agents is described. The new sensor relies on the coupling of the effective biocatalytic action of organophosphorus hydrolase (OPH) with a submersible amperometric probe design. This combination resu...

  7. 75 FR 143 - Lockhart Power Company; Notice of Application Accepted for Filing, Soliciting Motions To...

    Science.gov (United States)

    2010-01-04

    ... submersible turbine/generator unit in the hydro canal bank and provide for seasonal fluctuations of head pond... generating unit would have an installed capacity of 534 kW and an estimated hydraulic capacity of 280 cfs...

  8. Accident Tolerant Reactor Shutdown for NTP Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In brief, USNC's accident submersion safe drums are control drums where a small amount of fuel is added opposite to the neutron absorber and the drums impinge on the...

  9. Biodiversity, zoogeography and affinity of Orissa sponges

    Digital Repository Service at National Institute of Oceanography (India)

    Thomas, P.A.; Sree, A.; Bapuji, M.; Rao, K.M.; Murthy, K.S.R.

    . Along with coral reefs, the ridge reefs gained importance for the study of different coral populations. With the advent of SCUBA and submersibles scientists have been able to initiate careful studies of subtidal / benthic faunal communities. With the use...

  10. Proceedings of oceans '91

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    This volume contains the proceedings of the Oceans '91 Conference. Topics addressed include: ocean energy conversion, marine communications and navigation, ocean wave energy conversion, environmental modeling, global climate change, ocean minerals technology, oil spill technology, and submersible vehicles

  11. On the operational aspects of subsea systems

    Digital Repository Service at National Institute of Oceanography (India)

    Nayak, M.R.

    The scientific and commercial underwater activities in the next decades primarily in 'undersea vehicles' and 'manned submersibles' will be taking place in the oceans and ocean related technology. The paper underlines some of the operational aspects...

  12. incidence of heavy metals in kano metropolis drinking water sources

    African Journals Online (AJOL)

    userpc

    corrosion of brass fittings of certain submersible pumps and pipes used in borehole and taps specifically. The contamination of well with heavy metals might be due to seepage of sewage ... Chloride determination (Agumetric method):.

  13. SUBMERGED MACROPHYTE EFFECTS ON NUTRIENT EXCHANGES IN RIVERINE SEDIMENTS

    Science.gov (United States)

    Submersed macrophytes are important in nutrient cycling in marine and lacustrine systems, although their role in nutrient exchange in tidally-influenced riverine systems is not well studied. In the laboratory, plants significantly lowered porewater nutrient pools of riverine sedi...

  14. A Simulation Model on the Competition for Light of Meadow-forming and Canopy-forming Aquatic Macrophytes at High and Low Nutrient Availability

    National Research Council Canada - National Science Library

    Best, Elly

    2004-01-01

    A simulation model has been developed that focuses on the ability of two competing submersed macrophytes, meadow-forming and canopy-forming, to maintain their biomass under different environmental conditions...

  15. Impact of invasive aquatic macrophytes on the population and behavioral ecology of mosquitoes (Diptera: Culicidae)

    Science.gov (United States)

    A field survey, three outdoor cage enclosure experiments, and laboratory studies were conducted to elucidate the impact of the invasive aquatic weeds Eichhornia crassipes (floating water hyacinth), Ludwigia hexapetala (emergent water yellow-primrose), and Egeria densa (submersed Brazilian waterweed)...

  16. Catamaran type semisubmersible platform for offshore drilling

    Energy Technology Data Exchange (ETDEWEB)

    Pouget, G; Chevallier, J; Hampton, G

    1988-06-10

    A semi-submersible oil rig which allows the vertical storage of drilling tubes and drill pipes is presented. The structure which links the floaters to the bridge consists of hollow columns forming caissons and containing means for storing tubes.

  17. Impact of offshore placer mining experiments (PLAMEX) on the sediment size and heavy minerals

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.; Fernandes, D.

    Two offshore placer mining experiments (PLAMEX) were conducted using submersible pumps specially designed by Central Mechanical Engineering Research Institute (CMERI), Durgapur (India) at 8 m water depth in Kalbadevi Bay (PLAMEX-I), Ratnagiri...

  18. Explosives Removal from Groundwater of the Iowa Army Ammunition Plant in Continuous-Flow Laboratory Systems Planted with Aquatic and Wetland Plants

    National Research Council Canada - National Science Library

    Best, Elly

    1998-01-01

    A 49-day, continuous-flow, laboratory study was performed to evaluate the ability of two submersed and one emergent plant species to phytoremediate explosives-contaminated groundwater from the Iowa...

  19. Superconducting Electric Boost Pump for Nuclear Thermal Propulsion, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A submersible, superconducting electric boost pump sized to meet the needs of future Nuclear Thermal Propulsion systems in the 25,000 lbf thrust range is proposed....

  20. Unintentional Drowning

    Science.gov (United States)

    ... 13:178-182. U. S. Consumer Product Safety Commission. Safety barrier guidelines for home pools [online]. [cited 2012 May 3]. Available from URL: ... S. Consumer Product Safety Commission. Submersions related to non-pool and non- ...

  1. Northern Mariana Islands Marine Monitoring Team Sea Temperature Measurements

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Site specific monitoring of sea temperature is conducted using submersible temperature dataloggers at selected sites and depths around the islands of Saipan and Rota.

  2. Oceanographic data collected during the Mountains in the Sea: Exploring the New England Seamount Chain 2003 on RV Atlantis in North Atlantic Ocean from July 11, 2003 - July 19, 2003 (NODC Accession 0072308)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This summer, with the help of the Alvin submersible, a multidisciplinary team of scientists and educators visited several little known seamounts in the North...

  3. Genome-wide distribution and organization of microsatellites in plants: an insight into marker development in Brachypodium.

    Directory of Open Access Journals (Sweden)

    Humira Sonah

    Full Text Available Plant genomes are complex and contain large amounts of repetitive DNA including microsatellites that are distributed across entire genomes. Whole genome sequences of several monocot and dicot plants that are available in the public domain provide an opportunity to study the origin, distribution and evolution of microsatellites, and also facilitate the development of new molecular markers. In the present investigation, a genome-wide analysis of microsatellite distribution in monocots (Brachypodium, sorghum and rice and dicots (Arabidopsis, Medicago and Populus was performed. A total of 797,863 simple sequence repeats (SSRs were identified in the whole genome sequences of six plant species. Characterization of these SSRs revealed that mono-nucleotide repeats were the most abundant repeats, and that the frequency of repeats decreased with increase in motif length both in monocots and dicots. However, the frequency of SSRs was higher in dicots than in monocots both for nuclear and chloroplast genomes. Interestingly, GC-rich repeats were the dominant repeats only in monocots, with the majority of them being present in the coding region. These coding GC-rich repeats were found to be involved in different biological processes, predominantly binding activities. In addition, a set of 22,879 SSR markers that were validated by e-PCR were developed and mapped on different chromosomes in Brachypodium for the first time, with a frequency of 101 SSR markers per Mb. Experimental validation of 55 markers showed successful amplification of 80% SSR markers in 16 Brachypodium accessions. An online database 'BraMi' (Brachypodium microsatellite markers of these genome-wide SSR markers was developed and made available in the public domain. The observed differential patterns of SSR marker distribution would be useful for studying microsatellite evolution in a monocot-dicot system. SSR markers developed in this study would be helpful for genomic studies in Brachypodium

  4. Photosynthetic characteristics of an amphibious plant, Eleocharis vivipara: Expression of C4 and C3 modes in contrasting environments

    International Nuclear Information System (INIS)

    Ueno, Osamu; Samejima, Muneaki; Muto, Shoshi; Miyachi, Shigetoh

    1988-01-01

    Eleocharis vivipara Link, a freshwater amphibious leafless plant belonging to the Cyperaceae can grow in both terrestrial and submersed aquatic conditions. Two forms of E. vivipara obtained from these contrasting environments were examined for the characteristics associated with C 4 and C 3 photosynthesis. In the terrestrial form, the culms, which are photosynthetic organs, possess a Kranz-type anatomy typical of C 4 plants, and well-developed bundle-sheath cells contain numerous large chloroplasts. In the submersed form, the culms possess anatomical features characteristic of submersed aquatic plants, and the reduced bundle-sheath cells contain only a few small chloroplasts. 14 C pulse- 12 C chase experiments showed that the terrestrial form and the submersed form fix carbon by way of the C 4 pathway, with aspartate (40%) and malate (35%) as the main primary products, and by way of the C 3 pathway, with 3-phosphoglyceric acid (53%) and sugar phosphates (14%) as the main primary products, respectively. The terrestrial form showed photosynthetic enzyme activities typical of the NAD-malic enzyme-C 4 subtype, whereas the submersed form showed decreased activities of key C 4 enzymes and an increased ribulose 1,5-bisphosphate carboxylase activity. These data suggest that this species can differentiate into the C 4 mode under terrestrial conditions and into the C 3 mode under submersed conditions

  5. Storage Stability of Dried Microsclerotia of the Biological Control Pathogen Mycoleptodiscus Terrestris

    Science.gov (United States)

    2009-09-01

    packed in polyethylene bags, and stored at 4 ºC on 3/6/07, 5/15/07, 6/13/07, and 7/11/07. Dry material was shipped overnight in refrigerated...into plastic weigh boats for aquarium efficacy testing on hydrilla (see below) and for spore production bioassays. After use, the polyethylene bags were...Introduction to Fungi . 3rd ed. Cambridge, UK: Cambridge University Press. NOTE: The contents of this technical note are not to be used for advertising

  6. US Department of Agriculture/Corps of Engineers Cooperative Aquatic Plant Control Research. Annual Report for FY 1982. Biological and Chemical Control Technologies.

    Science.gov (United States)

    1984-08-01

    pollen. Fruits and seeds have not yet been observed in the United States. Pollination . Although the female hydrilla flower has been abundant at many U.S...The flowers can only be pollinated in the air. The female flower reaches the water surface by elongation of the hypanthium (flower "stalk"). The petals...Both the experimental herbicides N-252 and S-734 were effective against waterhyacinth at the treatment rate of 5.6 kg/ha (Table 30). Water lettuce was

  7. Drowning and near-drowning: experience of a university hospital in the Black Sea region.

    Science.gov (United States)

    Güzel, Ahmet; Duran, Latif; Paksu, Sule; Akdemir, Hızır Ufuk; Paksu, Muhammet Şükrü; Katı, Celal; Başol, Nurşah; Yılman, Metehan; Özsevik, Sevinç Nursev; Murat, Naci

    2013-01-01

    The aim of the study was to describe the characteristics of patients who applied to the Emergency Department (ED) due to submersion injury; to recognize the risk factors, complications, causes of death, and the educational needs of families and caregivers about unsafe environments for submersion; and to develop preventive strategies. All patients were analyzed retrospectively according to demographic features, clinical and laboratory findings, association between clinical variables and submersion injuries, and patient outcomes. Fifty-five patients with submersion injury were analyzed. The mean age of patients was 10.9 ± 4.7 years. The most common Szpilman clinical scores were Grade 1 (24 patients, 43.8%), Grade 2 (15 patients, 27.3%), and Grade 5 (10 patients, 18.2%). The common location of the submersion injuries included the sea (74.5%), pool (18.4%), bathtub (7.3%), river (3.6%), and lake (3.6%). A limited swimming ability or exhaustion and suffocation (49.1%) due to unknown reasons were the most common causes of submersion injury among all patients. Most complications were due to aspiration pneumonia and hypoxic ischemic encephalopathy (HIE). Thirty-nine patients (70.9%) were followed in the ED, while 16 patients (29.1%) were admitted to the pediatric intensive care unit (PICU); 11 patients (20.0%) died. All of the risk factors of drowning should be taken into account when designing preventive measures and family education. In addition, all pediatricians should be trained periodically about the complications of submersion and the treatment strategies, particularly in coastal cities and areas where drownings occur frequently.

  8. Use of Agrobacterium rhizogenes strain 18r12v and paromomycin selection for transformation of Brachypodium distachyon and Brachypodium sylvaticum

    Science.gov (United States)

    The genetic transformation of monocot grasses is a resource intensive process, the quality and efficiency of which is dependent in part upon the method of DNA introduction, as well as the ability to effectively separate transformed from wildtype tissue. Agrobacterium-mediated transformation of Brac...

  9. Conservation, Divergence, and Genome-Wide Distribution of PAL and POX A Gene Families in Plants.

    Science.gov (United States)

    Rawal, H C; Singh, N K; Sharma, T R

    2013-01-01

    Genome-wide identification and phylogenetic and syntenic comparison were performed for the genes responsible for phenylalanine ammonia lyase (PAL) and peroxidase A (POX A) enzymes in nine plant species representing very diverse groups like legumes (Glycine max and Medicago truncatula), fruits (Vitis vinifera), cereals (Sorghum bicolor, Zea mays, and Oryza sativa), trees (Populus trichocarpa), and model dicot (Arabidopsis thaliana) and monocot (Brachypodium distachyon) species. A total of 87 and 1045 genes in PAL and POX A gene families, respectively, have been identified in these species. The phylogenetic and syntenic comparison along with motif distributions shows a high degree of conservation of PAL genes, suggesting that these genes may predate monocot/eudicot divergence. The POX A family genes, present in clusters at the subtelomeric regions of chromosomes, might be evolving and expanding with higher rate than the PAL gene family. Our analysis showed that during the expansion of POX A gene family, many groups and subgroups have evolved, resulting in a high level of functional divergence among monocots and dicots. These results will act as a first step toward the understanding of monocot/eudicot evolution and functional characterization of these gene families in the future.

  10. Spray boom for selectively spraying a herbicidal composition onto dicots

    DEFF Research Database (Denmark)

    2012-01-01

    There is provided a method and spray boom for discriminating cereal crop (monocot) and weeds (dicots). The spray boom includes means for digitally recording an image of a selected area to be treated by a nozzle on the spray boom, whereby a plant material is identified based on a segmentation proc...

  11. The Ethiopian Flora Project

    DEFF Research Database (Denmark)

    Demissew, Sebsebe; Brochmann, Christian; Kelbessa, Ensermu

    2011-01-01

    The account reviews and analyses the scietific projects derived from activities in connection with the Ethiopian Flora Project, including the [Ethiopian] Monocot Project, the Afro-alpine "Sky-island" project, the Vegetation and Ecological Conditions of Plantations Project, the Fire Ecology Projec...

  12. Cross activity of orthologous WRKY transcription factors in wheat and Arabidopsis

    NARCIS (Netherlands)

    Poietti, S.; Bertini, L.; Ent, S. van der; Leon Reyes, H.A.; Pieterse, C.M.J.; Tucci, M.; Caporale, C.; Caruso, C.

    2011-01-01

    WRKY proteins are transcription factors involved in many plant processes including plant responses to pathogens. Here, the cross activity of TaWRKY78 from the monocot wheat and AtWRKY20 from the dicot Arabidopsis on the cognate promoters of the orthologous PR4-type genes wPR4e and AtHEL of wheat and

  13. Virus-induced gene silencing in diverse maize lines using the Brome Mosaic virus-based silencing vector

    Science.gov (United States)

    Virus-induced gene silencing (VIGS) is a widely used tool for gene function studies in many plant species, though its use in monocots has been limited. Using a Brome mosaic virus (BMV) vector designed to silence the maize phytoene desaturase gene, a genetically diverse set of maize inbred lines was ...

  14. Novel gene expression tools for rice biotechnology

    Science.gov (United States)

    Biotechnology is an effective and important method of improving both quality and agronomic traits in rice. We are developing novel molecular tools for genetic engineering, with a focus on developing novel transgene expression control elements (i.e. promoters) for rice. A suite of monocot grass promo...

  15. Functional leaf attributes predict litter decomposition rate in herbaceous plants

    NARCIS (Netherlands)

    Cornelissen, J. H C; Thompson, K.

    1997-01-01

    We tested the hypothesis that functional attributes of living leaves provide a basis for predicting the decomposition rate of leaf litter. The data were obtained from standardized screening tests on 38 British herbaceous species. Graminoid monocots had physically tougher leaves with higher silicon

  16. Identification and characterization of putative conserved IAM ...

    African Journals Online (AJOL)

    Available putative AMI sequences from a wide array of monocot and dicot plants were identified and the phylogenetic tree was constructed and analyzed. We identified in this tree, a clade that contained sequences from species across the plant kingdom suggesting that AMI is conserved and may have a primary role in plant ...

  17. Miscellaneous information

    NARCIS (Netherlands)

    NN,

    1965-01-01

    C. A. Backer & R. C. Bakhuizen van den Brink, Flora of Java, volume 2, will be published about New year 1966. This volume will deal with the second half of the dicots; the third and last volume will give the monocots. The 641 pages of text of this volume will be preceded by a 72-page essay by Dr. C.

  18. Durable broad-spectrum powdery mildew resistance in pea er1 plants is conferred by natural loss-of-function mutations in PsMLO1

    NARCIS (Netherlands)

    Humphry, M.; Reinstädler, A.; Ivanov, S.; Bisseling, T.; Panstruga, R.

    2011-01-01

    Loss-of-function alleles of plant-specific MLO (Mildew Resistance Locus O) genes confer broad-spectrum powdery mildew resistance in monocot (barley) and dicot (Arabidopsis thaliana, tomato) plants. Recessively inherited powdery mildew resistance in pea (Pisum sativum) er1 plants is, in many aspects,

  19. Mating-type locus characterization and variation in Pyrenophora semeniperda

    Science.gov (United States)

    Julie Leanna Henry

    2015-01-01

    Pyrenophora semeniperda is a generalist fungal pathogen that occurs primarily on monocot seed hosts. It is in the phylum Ascomycota, which includes both self-compatible (homothallic) and self-incompatible (heterothallic) species. Homothallic fungal species contain complementary mating-type (MAT) idiomorphs in a single unikaryotic strain, while heterothallic strains...

  20. Compositional gradients in Gramineae genes

    DEFF Research Database (Denmark)

    Wong, Gane Ka-Shu; Wang, Jun; Tao, Lin

    2002-01-01

    In this study, we describe a property of Gramineae genes, and perhaps all monocot genes, that is not observed in eudicot genes. Along the direction of transcription, beginning at the junction of the 5'-UTR and the coding region, there are gradients in GC content, codon usage, and amino-acid usage...

  1. Effective Agrobacterium–mediated transformation of pineapple with ...

    African Journals Online (AJOL)

    user7

    Agrobacterium tumefaciens strain LBA4404 harboring a plant expression vector pUHA1 containing a ... hybridization of this self-incompatible monocot species, only a few new hybrids ... CYP1A1 is a member of the P450 gene family isolated.

  2. A survey of root pressure in 53 Asian species of bamboo

    Science.gov (United States)

    Fusheng Wang; Xinli Tian; Yulong Ding; Xianchong Wan; M. T. Tyree

    2011-01-01

    Introduction. Root pressure is a potentially important mechanism for dissolving embolisms in previously cavitated vessels, but the occurrence of root pressure is not a universal property in plants. Material and methods. We suggest that root pressure might be more common in monocots than dicots because in dicots, cambial growth...

  3. Conservation, Divergence, and Genome-Wide Distribution of PAL and POX A Gene Families in Plants

    Directory of Open Access Journals (Sweden)

    H. C. Rawal

    2013-01-01

    Full Text Available Genome-wide identification and phylogenetic and syntenic comparison were performed for the genes responsible for phenylalanine ammonia lyase (PAL and peroxidase A (POX A enzymes in nine plant species representing very diverse groups like legumes (Glycine max and Medicago truncatula, fruits (Vitis vinifera, cereals (Sorghum bicolor, Zea mays, and Oryza sativa, trees (Populus trichocarpa, and model dicot (Arabidopsis thaliana and monocot (Brachypodium distachyon species. A total of 87 and 1045 genes in PAL and POX A gene families, respectively, have been identified in these species. The phylogenetic and syntenic comparison along with motif distributions shows a high degree of conservation of PAL genes, suggesting that these genes may predate monocot/eudicot divergence. The POX A family genes, present in clusters at the subtelomeric regions of chromosomes, might be evolving and expanding with higher rate than the PAL gene family. Our analysis showed that during the expansion of POX A gene family, many groups and subgroups have evolved, resulting in a high level of functional divergence among monocots and dicots. These results will act as a first step toward the understanding of monocot/eudicot evolution and functional characterization of these gene families in the future.

  4. Journal of Biosciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Using RNA extracted from Zingiber officinale rhizomes and primers designed according to the conservative regions of monocot mannose-binding lectins, the full-length cDNA of Z. officinale agglutinin (ZOA) was cloned by rapid amplification of cDNA ends (RACE). The full-length cDNA of zoa was 746 bp and contained a ...

  5. Expeditions and other exploration

    NARCIS (Netherlands)

    NN,

    1969-01-01

    The Flora of Ceylon Project (continued from p. 1684). This project of the Smithsonian Institution stands in Ceylon under the responsibility of Dr. R. Read, who himself is working on Monocots. Otherwise it is performed by visiting botanists who get transport, drying facilities, and can amply do field

  6. Complex Self-Incompatibility Systems in Ranunculus acris L. and Beta vulgaris L

    DEFF Research Database (Denmark)

    Lundqvist, A.; Østerbye, U.; Larsen, K.

    1973-01-01

    The families Ranunculaceae and Chenopodiaceae, presumably belonging to a dicot evolutionary branch with ancestral basis shared with the monocots, both show a mechanism of self- and cross-incompatibility involving more than one incompatibility locus (S-locus) and requiring that all of the S...

  7. Failure to transmit avian vacuolar myelinopathy to mallard ducks

    Science.gov (United States)

    Larsen, R.S.; Nutter, F.B.; Augspurger, T.; Rocke, T.E.; Thomas, N.J.; Stoskopf, M.K.

    2003-01-01

    Avian vacuolar myelinopathy (AVM) is a neurologic disease that has been diagnosed in free-ranging birds in the southeastern United States. Bald eagles (Haliaeetus leuocephalus), American coots (Fulica americana), and mallards (Anas platyrhynchos) have been affected. Previous investigations have not determined the etiology of this disease. In November and December 2002, we attempted to induce AVM in game-farmed mallards through four, 7-day exposure trials. Mallards were housed in six groups of eight, with two of these groups serving as controls. One group was housed with AVM-affected coots; one group was tube fed daily with water from the lake where affected coots were captured; one group was tube fed daily with aquatic vegetation (Hydrilla verticillata) from the same lake; and another group was tube fed daily with sediment from the lake. No ducks exhibited clinical neurologic abnormalities consistent with AVM and no evidence of AVM was present at histopathologic examination of brain tissue. Although limitations in sample size, quantity of individual doses, frequency of dose administration, duration of exposure, and timing of these trials restrict the interpretation of the findings, AVM was not readily transmitted by direct contact, water, hydrilla, or sediment in this investigation.

  8. Aquatic arsenic: phytoremediation using floating macrophytes.

    Science.gov (United States)

    Rahman, M Azizur; Hasegawa, H

    2011-04-01

    Phytoremediation, a plant based green technology, has received increasing attention after the discovery of hyperaccumulating plants which are able to accumulate, translocate, and concentrate high amount of certain toxic elements in their above-ground/harvestable parts. Phytoremediation includes several processes namely, phytoextraction, phytodegradation, rhizofiltration, phytostabilization and phytovolatilization. Both terrestrial and aquatic plants have been tested to remediate contaminated soils and waters, respectively. A number of aquatic plant species have been investigated for the remediation of toxic contaminants such as As, Zn, Cd, Cu, Pb, Cr, Hg, etc. Arsenic, one of the deadly toxic elements, is widely distributed in the aquatic systems as a result of mineral dissolution from volcanic or sedimentary rocks as well as from the dilution of geothermal waters. In addition, the agricultural and industrial effluent discharges are also considered for arsenic contamination in natural waters. Some aquatic plants have been reported to accumulate high level of arsenic from contaminated water. Water hyacinth (Eichhornia crassipes), duckweeds (Lemna gibba, Lemna minor, Spirodela polyrhiza), water spinach (Ipomoea aquatica), water ferns (Azolla caroliniana, Azolla filiculoides, and Azolla pinnata), water cabbage (Pistia stratiotes), hydrilla (Hydrilla verticillata) and watercress (Lepidium sativum) have been studied to investigate their arsenic uptake ability and mechanisms, and to evaluate their potential in phytoremediation technology. It has been suggested that the aquatic macrophytes would be potential for arsenic phytoremediation, and this paper reviews up to date knowledge on arsenic phytoremediation by common aquatic macrophytes. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Biochar amendment for batch composting of nitrogen rich organic waste: Effect on degradation kinetics, composting physics and nutritional properties.

    Science.gov (United States)

    Jain, Mayur Shirish; Jambhulkar, Rohit; Kalamdhad, Ajay S

    2018-04-01

    Composting is an efficient technology to reduce pathogenic bodies and stabilize the organic matter in organic wastes. This research work investigates an effect of biochar as amendment to improve the composting efficiency and its effect on degradation kinetics, physical and nutritional properties. Biochar (2.5, 5 and 10% (w/w)) were added into a mixture of Hydrilla verticillata, cow dung and sawdust having ratio of 8:1:1 (control), respectively. Biochar addition resulted in advanced thermophilic temperatures (59 °C) and could improve the physical properties of composting process. Owing to addition of 5% biochar as a bulking agent in composting mixture, the final product from composting, total nitrogen increased by 45% compared to the other trials, and air-filled porosity decreased by 39% and was found to be within recommended range from literature studies. Considering temperature, degradation rate and nitrogen transformation the amendment of 5% biochar is recommended for Hydrilla verticillata composting. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. The mitochondrial genome of an aquatic plant, Spirodela polyrhiza.

    Directory of Open Access Journals (Sweden)

    Wenqin Wang

    Full Text Available BACKGROUND: Spirodela polyrhiza is a species of the order Alismatales, which represent the basal lineage of monocots with more ancestral features than the Poales. Its complete sequence of the mitochondrial (mt genome could provide clues for the understanding of the evolution of mt genomes in plant. METHODS: Spirodela polyrhiza mt genome was sequenced from total genomic DNA without physical separation of chloroplast and nuclear DNA using the SOLiD platform. Using a genome copy number sensitive assembly algorithm, the mt genome was successfully assembled. Gap closure and accuracy was determined with PCR products sequenced with the dideoxy method. CONCLUSIONS: This is the most compact monocot mitochondrial genome with 228,493 bp. A total of 57 genes encode 35 known proteins, 3 ribosomal RNAs, and 19 tRNAs that recognize 15 amino acids. There are about 600 RNA editing sites predicted and three lineage specific protein-coding-gene losses. The mitochondrial genes, pseudogenes, and other hypothetical genes (ORFs cover 71,783 bp (31.0% of the genome. Imported plastid DNA accounts for an additional 9,295 bp (4.1% of the mitochondrial DNA. Absence of transposable element sequences suggests that very few nuclear sequences have migrated into Spirodela mtDNA. Phylogenetic analysis of conserved protein-coding genes suggests that Spirodela shares the common ancestor with other monocots, but there is no obvious synteny between Spirodela and rice mtDNAs. After eliminating genes, introns, ORFs, and plastid-derived DNA, nearly four-fifths of the Spirodela mitochondrial genome is of unknown origin and function. Although it contains a similar chloroplast DNA content and range of RNA editing as other monocots, it is void of nuclear insertions, active gene loss, and comprises large regions of sequences of unknown origin in non-coding regions. Moreover, the lack of synteny with known mitochondrial genomic sequences shed new light on the early evolution of monocot

  11. Design and analysis of a single stage to orbit nuclear thermal rocket reactor engine

    International Nuclear Information System (INIS)

    Labib, Satira; King, Jeffrey

    2015-01-01

    Graphical abstract: - Highlights: • Three NTR reactors are optimized for the single stage launch of 1–15 MT payloads. • The proposed rocket engines have specific impulses in excess of 700 s. • Reactivity and submersion criticality requirements are satisfied for each reactor. - Abstract: Recent advances in the development of high power density fuel materials have renewed interest in nuclear thermal rockets (NTRs) as a viable propulsion technology for future space exploration. This paper describes the design of three NTR reactor engines designed for the single stage to orbit launch of payloads from 1 to 15 metric tons. Thermal hydraulic and rocket engine analyses indicate that the proposed rocket engines are able to reach specific impulses in excess of 800 s. Neutronics analyses performed using MCNP5 demonstrate that the hot excess reactivity, shutdown margin, and submersion criticality requirements are satisfied for each NTR reactor. The reactors each consist of a 40 cm diameter core packed with hexagonal tungsten cermet fuel elements. The core is surrounded by radial and axial beryllium reflectors and eight boron carbide control drums. The 40 cm long reactor meets the submersion criticality requirements (a shutdown margin of at least $1 subcritical in all submersion scenarios) with no further modifications. The 80 and 120 cm long reactors include small amounts of gadolinium nitride as a spectral shift absorber to keep them subcritical upon submersion in seawater or wet sand following a launch abort

  12. Design and analysis of a single stage to orbit nuclear thermal rocket reactor engine

    Energy Technology Data Exchange (ETDEWEB)

    Labib, Satira, E-mail: Satira.Labib@duke-energy.com; King, Jeffrey, E-mail: kingjc@mines.edu

    2015-06-15

    Graphical abstract: - Highlights: • Three NTR reactors are optimized for the single stage launch of 1–15 MT payloads. • The proposed rocket engines have specific impulses in excess of 700 s. • Reactivity and submersion criticality requirements are satisfied for each reactor. - Abstract: Recent advances in the development of high power density fuel materials have renewed interest in nuclear thermal rockets (NTRs) as a viable propulsion technology for future space exploration. This paper describes the design of three NTR reactor engines designed for the single stage to orbit launch of payloads from 1 to 15 metric tons. Thermal hydraulic and rocket engine analyses indicate that the proposed rocket engines are able to reach specific impulses in excess of 800 s. Neutronics analyses performed using MCNP5 demonstrate that the hot excess reactivity, shutdown margin, and submersion criticality requirements are satisfied for each NTR reactor. The reactors each consist of a 40 cm diameter core packed with hexagonal tungsten cermet fuel elements. The core is surrounded by radial and axial beryllium reflectors and eight boron carbide control drums. The 40 cm long reactor meets the submersion criticality requirements (a shutdown margin of at least $1 subcritical in all submersion scenarios) with no further modifications. The 80 and 120 cm long reactors include small amounts of gadolinium nitride as a spectral shift absorber to keep them subcritical upon submersion in seawater or wet sand following a launch abort.

  13. SUPERAÇÃO DE DORMÊNCIA EM SEMENTES DE JITIRANA ( Merremia aegyptia L.

    Directory of Open Access Journals (Sweden)

    Elaíne Welk Lopes Pereira

    2007-01-01

    Full Text Available The objective of work was evaluated four methods of superation of dormancy in Jitirana (Merremia aegyptia. The treatments used were: 1- Checking, 2 - Submersion in the hot water at 80ºC by one minute, 3 - Mechanic escarification by five minutes; 4 - Submersion in the sulfuric acid by six minutes, 5 - Submersion in the sulfuric acid by ten minutes. The experimental design was completely randomized with four replications. The plot was formed by sample with 50 seeds. The traits evaluated were: fresh weight, dry weight, height of seedling, length of root, percentage of germination and index of velocity of germination. The seeds treated with sulfuric acid showed bigger percentage of germination. The treatments with mechanic escarification and sulfuric acid (10 minutes showed bigger index of velocity of germination.

  14. Development and setting of a time-lapse video camera system for the Antarctic lake observation

    Directory of Open Access Journals (Sweden)

    Sakae Kudoh

    2010-11-01

    Full Text Available A submersible video camera system, which aimed to record the growth image of aquatic vegetation in Antarctic lakes for one year, was manufactured. The system consisted of a video camera, a programmable controller unit, a lens-cleaning wiper with a submersible motor, LED lights, and a lithium ion battery unit. Changes of video camera (High Vision System and modification of the lens-cleaning wiper allowed higher sensitivity and clearer recording images compared to the previous submersible video without increasing the power consumption. This system was set on the lake floor in Lake Naga Ike (a tentative name in Skarvsnes in Soya Coast, during the summer activity of the 51th Japanese Antarctic Research Expedition. Interval record of underwater visual image for one year have been started by our diving operation.

  15. Photosynthetic characteristics of an amphibious plant, Eleocharis vivipara: Expression of C4 and C3 modes in contrasting environments

    Science.gov (United States)

    Ueno, Osamu; Samejima, Muneaki; Muto, Shoshi; Miyachi, Shigetoh

    1988-01-01

    Eleocharis vivipara Link, a freshwater amphibious leafless plant belonging to the Cyperaceae can grow in both terrestrial and submersed aquatic conditions. Two forms of E. vivipara obtained from these contrasting environments were examined for the characteristics associated with C4 and C3 photosynthesis. In the terrestrial form (δ 13C values = -13.5 to -15.4‰, where ‰ is parts per thousand), the culms, which are photosynthetic organs, possess a Kranz-type anatomy typical of C4 plants, and well-developed bundle-sheath cells contain numerous large chloroplasts. In the submersed form (δ 13C value = -25.9‰), the culms possess anatomical features characteristic of submersed aquatic plants, and the reduced bundle-sheath cells contain only a few small chloroplasts. 14C pulse-12C chase experiments showed that the terrestrial form and the submersed form fix carbon by way of the C4 pathway, with aspartate (40%) and malate (35%) as the main primary products, and by way of the C3 pathway, with 3-phosphoglyceric acid (53%) and sugar phosphates (14%) as the main primary products, respectively. The terrestrial form showed photosynthetic enzyme activities typical of the NAD-malic enzyme-C4 subtype, whereas the submersed form showed decreased activities of key C4 enzymes and an increased ribulose 1,5-bisphosphate carboxylase (EC 4.1.1.39) activity. These data suggest that this species can differentiate into the C4 mode under terrestrial conditions and into the C3 mode under submersed conditions. Images PMID:16593980

  16. Shivering heat production and core cooling during head-in and head-out immersion in 17 degrees C water.

    Science.gov (United States)

    Pretorius, Thea; Cahill, Farrell; Kocay, Sheila; Giesbrecht, Gordon G

    2008-05-01

    Many cold-water scenarios cause the head to be partially or fully immersed (e.g., ship wreck survival, scuba diving, cold-water adventure swim racing, cold-water drowning, etc.). However, the specific effects of head cold exposure are minimally understood. This study isolated the effect of whole-head submersion in cold water on surface heat loss and body core cooling when the protective shivering mechanism was intact. Eight healthy men were studied in 17 degrees C water under four conditions: the body was either insulated or exposed, with the head either out of the water or completely submersed under the water within each insulated/exposed subcondition. Submersion of the head (7% of the body surface area) in the body-exposed condition increased total heat loss by 11% (P < 0.05). After 45 min, head-submersion increased core cooling by 343% in the body-insulated subcondition (head-out: 0.13 +/- 0.2 degree C, head-in: 0.47 +/- 0.3 degree C; P < 0.05) and by 56% in the body-exposed subcondition (head-out: 0.40 +/- 0.3 degree C and head-in: 0.73 +/- 0.6 degree C; P < 0.05). In both body-exposed and body-insulated subconditions, head submersion increased the rate of core cooling disproportionally more than the relative increase in total heat loss. This exaggerated core-cooling effect is consistent with a head cooling induced reduction of the thermal core, which could be stimulated by cooling of thermosensitive and/or trigeminal receptors in the scalp, neck, and face. These cooling effects of head submersion are not prevented by shivering heat production.

  17. The effects of plant traits and phylogeny on soil-to-plant transfer of 99Tc

    International Nuclear Information System (INIS)

    Willey, N.J.; Tang, S.; McEwen, A.; Hicks, S.

    2010-01-01

    Assessments of the behaviour of 99 Tc in terrestrial environments necessitate predicting soil-to-plant transfer. An experiment with 116 plant taxa showed that 99 Tc transfer to plants was positively related to plant dry weight but negatively related to % dry matter and age at exposure. Activities of 99 Tc analysed by hierarchical ANOVA coded with an angiosperm phylogeny revealed significant effects, with 55% of the variance between species explained at the Ordinal level and above. Monocots had significantly lower transfer of 99 Tc than Eudicots, within which Caryophyllales > Solanales > Malvales > Brassicales > Asterales > Fabales. There was a significant phylogenetic signal in soil-to-plant transfer of 99 Tc. This phylogenetic signal is used to suggest that, for example, a nominal Tc Transfer Factor of 5 could be adjusted to 2.3 for Monocots and 5.3 for Eudicots.

  18. Molecular systematics and historical biogeography of Araceae at a worldwide scale and in Southeast Asia

    OpenAIRE

    Nauheimer, Lars

    2012-01-01

    This dissertation addresses the biogeographic history of the Araceae family and of one of its largest genera, Alocasia. With >3300 species, Araceae are among the largest families of flowering plants. It is the monocot lineage with the deepest fossil record, reaching back to the Early Cretaceous. Araceae are distributed worldwide, but >3100 species occur in the tropical regions of the Americas, Asia, Africa, and Australia; most fossils from the Late Cretaceous and many younger ones come from th...

  19. Microarray and Proteomic Analysis of Brassinosteroid- and Gibberellin-Regulated Gene and Protein Expression in Rice

    OpenAIRE

    Yang, Guangxiao; Komatsu, Setsuko

    2016-01-01

    Brassinosteroid (BR) and gibberellin (GA) are two groups of plant growth regulators essential for normal plant growth and development. To gain insight into the molecular mechanism by which BR and GA regulate the growth and development of plants, especially the monocot plant rice, it is necessary to identify and analyze more genes and proteins that are regulated by them. With the availability of draft sequences of two major types, japonica and indica rice, it has become possible to analyze exp...

  20. Identification of an attenuated barley stripe mosaic virus for the virus-induced gene silencing of pathogenesis-related wheat genes

    OpenAIRE

    Buhrow, Leann M.; Clark, Shawn M.; Loewen, Michele C.

    2016-01-01

    Background Virus-induced gene silencing (VIGS) has become an emerging technology for the rapid, efficient functional genomic screening of monocot and dicot species. The barley stripe mosaic virus (BSMV) has been described as an effective VIGS vehicle for the evaluation of genes involved in wheat and barley phytopathogenesis; however, these studies have been obscured by BSMV-induced phenotypes and defense responses. The utility of BSMV VIGS may be improved using a BSMV genetic background which...

  1. Uso de Glifosato en Plantaciones Forestales

    OpenAIRE

    Kogan, Marcelo; Alister, Claudio

    2010-01-01

    Under Chilean conditions the lack of weed control at forest tree establishment results in an average of at least 60% less biomass accumulation during the first year of growth of radiate pine or eucaliptus, and glyphosate offers a series of advantages in forestry weed management because its activity in both herbaceous weed groups, monocots and dicots, as well as annuals, biennials and perennials. Also, its efficacy in woody undesirable vegetation makes glyphosate a very important herbicide tha...

  2. Interkingdom signaling: The role of homoserine lactones in early responses and resistance in barley (Hordeum vulgare L.)

    OpenAIRE

    Rankl, Simone

    2017-01-01

    N-Acyl-D/L-homoserine lactones (AHLs) are produced as microbial signaling compounds during bacterial intra- and inter-specific communication in the rhizosphere. Thus, plants are naturally exposed to these compounds and respond with tissue-specific reactions. In the present study the impact of AHLs on the monocot barley (Hordeum vulgare L.) was investigated. The treatment with C8- and C12- homoserine lactones (HSL) resulted in root and shoot biomass gain as well as in the formation of lat...

  3. Structure of Hordeum vulgare NADPH-dependent thioredoxin reductase 2. Unwinding the reaction mechanism

    DEFF Research Database (Denmark)

    Kirkensgaard, Kristine Groth; Hägglund, Per; Finnie, Christine

    2009-01-01

    to the active form. Here, the first crystal structure of a cereal NTR, HvNTR2 from Hordeum vulgare (barley), is presented, which is also the first structure of a monocot plant NTR. The structure was determined at 2.6 A resolution and refined to an R (cryst) of 19.0% and an R (free) of 23.8%. The dimeric protein...

  4. Phylogenetic analysis, subcellular localization, and expression patterns of RPD3/HDA1 family histone deacetylases in plants

    OpenAIRE

    Alinsug, Malona V; Yu, Chun-Wei; Wu, Keqiang

    2009-01-01

    Abstract Background Although histone deacetylases from model organisms have been previously identified, there is no clear basis for the classification of histone deacetylases under the RPD3/HDA1 superfamily, particularly on plants. Thus, this study aims to reconstruct a phylogenetic tree to determine evolutionary relationships between RPD3/HDA1 histone deacetylases from six different plants representing dicots with Arabidopsis thaliana, Populus trichocarpa, and Pinus taeda, monocots with Oryz...

  5. Loss and recovery of Arabidopsis-type telomere repeat sequences 5'-(TTTAGGG)(n)-3' in the evolution of a major radiation of flowering plants.

    OpenAIRE

    Adams, S. P.; Hartman, T. P.; Lim, K. Y.; Chase, M. W.; Bennett, M. D.; Leitch, I. J.; Leitch, A. R.

    2001-01-01

    Fluorescent in situ hybridization and Southern blotting were used for showing the predominant absence of the Arabidopsis-type telomere repeat sequence (TRS) 5'-(TTTAGGG)(n)-3' (the 'typical' telomere) in a monocot clade which comprises up to 6300 species within Asparagales. Initially, two apparently disparate genera that lacked the typical telomere were identified. Here, we used the new angiosperm phylogenetic classification for predicting in which other related families such telomeres might ...

  6. Phylogenetic footprint of the plant clock system in angiosperms: evolutionary processes of Pseudo-Response Regulators

    Directory of Open Access Journals (Sweden)

    Saito Shigeru

    2010-05-01

    Full Text Available Abstract Background Plant circadian clocks regulate many photoperiodic and diurnal responses that are conserved among plant species. The plant circadian clock system has been uncovered in the model plant, Arabidopsis thaliana, using genetics and systems biology approaches. However, it is still not clear how the clock system had been organized in the evolutionary history of plants. We recently revealed the molecular phylogeny of LHY/CCA1 genes, one of the essential components of the clock system. The aims of this study are to reconstruct the phylogenetic relationships of angiosperm clock-associated PRR genes, the partner of the LHY/CCA1 genes, and to clarify the evolutionary history of the plant clock system in angiosperm lineages. Results In the present study, to investigate the molecular phylogeny of PRR genes, we performed two approaches: reconstruction of phylogenetic trees and examination of syntenic relationships. Phylogenetic analyses revealed that PRR genes had diverged into three clades prior to the speciation of monocots and eudicots. Furthermore, copy numbers of PRR genes have been independently increased in monocots and eudicots as a result of ancient chromosomal duplication events. Conclusions Based on the molecular phylogenies of both PRR genes and LHY/CCA1 genes, we inferred the evolutionary process of the plant clock system in angiosperms. This scenario provides evolutionary information that a common ancestor of monocots and eudicots had retained the basic components required for reconstructing a clock system and that the plant circadian clock may have become a more elaborate mechanism after the speciation of monocots and eudicots because of the gene expansion that resulted from polyploidy events.

  7. Bioenergy potential of eight common aquatic weeds

    Energy Technology Data Exchange (ETDEWEB)

    Abbasi, S.A.; Nipaney, P.C.; Schaumberg, G.D. (Pondicherry (Central) Univ. (IN). Salim Ali School of Ecology)

    1990-01-01

    Eight common aquatic weeds Salvinia molesta, Hydrilla verticillata, Nymphaea stellata, Azolla pinnata, Ceratopteris sp. Scirpus sp. Cyperus sp, and Utricularia reticulata were digested anaerobically to produce methane. The carbon to nitrogen (C/N) ratio, carbon to phosphorus (C/P) ratio, and the volatile solids (VS) content of the weeds varied widely. No trend between these factors and the methane yield was discernable; the possible reasons are discussed. The energy potential of the weeds per unit area of the weed crop was worked out. Natural stands of salvinia, such as the one employed in the present investigation, would yield energy (methane) of the order of 10{sup 8} Kcal/ha/yr. (author).

  8. Aquatic weeds: their implications in Indian nuclear industry

    International Nuclear Information System (INIS)

    Rao, T.S.; Anup Kumar, B.; Aruna Jyothi, K.; Satpathy, K.K.

    2000-01-01

    The aquatic weed infestation of KAPS cooling water system, MAPS open reservoir, and the growth of filamentous algae and bacteria in the feed water unit of HWP (Kota), was investigated. The aquatic weeds identified were: Ceratophyllum, Elodea, Hydrilla verticillata, Najas and Vallisneria species. However, at HWP (Kota) filamentous alga (Nostoc punchiformis) and bacteria (Sphaerotilus natans) were found in plenty. The metabolic products when assayed in the form of total carbohydrate content released by weeds was 3.7 mg gm -1 biomass. The metabolic products adsorb on to the resin matrix and impaired its performance at HWP (K), enhanced bacterial growth on the resin beads and furthered resin deterioration. Besides, the growth of aquatic weeds also influenced the pH of the cooling water, thereby vitiating the water treatment programme. (author)

  9. Does mechanical disturbance affect the performance and species composition of submerged macrophyte communities?

    Science.gov (United States)

    Zhang, Qian; Xu, Ying-Shou; Huang, Lin; Xue, Wei; Sun, Gong-Qi; Zhang, Ming-Xiang; Yu, Fei-Hai

    2014-05-01

    Submerged macrophyte communities are frequently subjected to disturbance of various frequency and strength. However, there is still little experimental evidence on how mechanical disturbance affects the performance and species composition of such plant communities. In a greenhouse experiment, we constructed wetland communities consisting of five co-occurring clonal submerged macrophyte species (Hydrilla verticillata, Elodea canadensis, Ceratophyllum demersum, Chara fragilis, and Myriophyllum spicatum) and subjected these communities to three mechanical disturbance regimes (no, moderate and strong disturbance). Strong mechanical disturbance greatly decreased overall biomass, number of shoot nodes and total shoot length, and increased species diversity (evenness) of the total community. It also substantially decreased the growth of the most abundant species (H. verticillata), but did not affect growth of the other four species. Our data reveal that strong disturbance can have different effects on different submerged macrophyte species and thus alters the performance and species composition of submerged macrophyte communities.

  10. Gα and regulator of G-protein signaling (RGS) protein pairs maintain functional compatibility and conserved interaction interfaces throughout evolution despite frequent loss of RGS proteins in plants.

    Science.gov (United States)

    Hackenberg, Dieter; McKain, Michael R; Lee, Soon Goo; Roy Choudhury, Swarup; McCann, Tyler; Schreier, Spencer; Harkess, Alex; Pires, J Chris; Wong, Gane Ka-Shu; Jez, Joseph M; Kellogg, Elizabeth A; Pandey, Sona

    2017-10-01

    Signaling pathways regulated by heterotrimeric G-proteins exist in all eukaryotes. The regulator of G-protein signaling (RGS) proteins are key interactors and critical modulators of the Gα protein of the heterotrimer. However, while G-proteins are widespread in plants, RGS proteins have been reported to be missing from the entire monocot lineage, with two exceptions. A single amino acid substitution-based adaptive coevolution of the Gα:RGS proteins was proposed to enable the loss of RGS in monocots. We used a combination of evolutionary and biochemical analyses and homology modeling of the Gα and RGS proteins to address their expansion and its potential effects on the G-protein cycle in plants. Our results show that RGS proteins are widely distributed in the monocot lineage, despite their frequent loss. There is no support for the adaptive coevolution of the Gα:RGS protein pair based on single amino acid substitutions. RGS proteins interact with, and affect the activity of, Gα proteins from species with or without endogenous RGS. This cross-functional compatibility expands between the metazoan and plant kingdoms, illustrating striking conservation of their interaction interface. We propose that additional proteins or alternative mechanisms may exist which compensate for the loss of RGS in certain plant species. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  11. Morphological responses of crop and weed species of different growth forms to ultraviolet-B radiation

    International Nuclear Information System (INIS)

    Barnes, P.W.; Flint, S.D.; Caldwell, M.M.

    1990-01-01

    The influence of ultraviolet-B (UV-B) radiation (280-320 nanometers) on the morphology of 12 common dicot and monocot crop or weed species was examined to determine whether any common responses could be found that might, in turn, be useful in predicting possible changes in competitive balance under solar UV-B enhancement. Under glasshouse conditions, UV-B exposure (simulating a 20% reduction in stratospheric ozone at Logan, Utah) was found to reduce leaf blade and internode lengths and increase leaf and axillary shoot production in several species. Overall, the directions of these trends were similar in the majority of species that exhibited a significant response. These morphological changes occurred without any significant reduction in total shoot dry matter production. There was no clear distinction in the response of crops and weeds, though monocots were found to be generally more responsive than dicots. Previous work in dense canopies has shown that the photomorphogenetic effects of UV-B alter leaf placement and thereby influence competition for light. Our results suggest that, under these conditions, changes in competitive balance resulting from increased UV-B might be expected more frequently when monocots are involved in mixtures, rather than mixtures of only dicots

  12. Cold seep communities in the deep eastern Mediterranean Sea: composition, symbiosis and spatial distribution on mud volcanoes

    NARCIS (Netherlands)

    Olu-Le Roy, K; Sibuet, M.; Fiala-Medioni, A.; Gofas, S; Salas, C.; Mariotti, A.; Foucher, J.-P.; Woodside, J.M.

    2004-01-01

    Two mud volcano fields were explored during the French-Dutch MEDINAUT cruise (1998) with the submersible NAUTILE, one south of Crete along the Mediteranean Ridge at about 2000 m depth (Olimpi mud field) and the other south of Turkey between 1700 and 2000 m depth (Anaximander mud field) where high

  13. Noble gas systematics of submarine alkalic lavas near the Hawaiian hotspot

    NARCIS (Netherlands)

    Hanyu, T.; Clague, D.A.; Kaneoka, I.; Dunai, T.J.; Davies, G.R.

    2005-01-01

    Noble gas isotopic ratios were determined for submarine alkalic volcanic rocks distributed around the Hawaiian islands to constrain the origin of such alkalic volcanism and hence understand the details of mantle upwelling beneath Hawaii. Samples were collected by dredging or using submersibles from

  14. A mapping from the unitary to doubly stochastic matrices and symbols on a finite set

    Science.gov (United States)

    Karabegov, Alexander V.

    2008-11-01

    We prove that the mapping from the unitary to doubly stochastic matrices that maps a unitary matrix (ukl) to the doubly stochastic matrix (|ukl|2) is a submersion at a generic unitary matrix. The proof uses the framework of operator symbols on a finite set.

  15. [Near-Drowning with Good Outcome after ECMO-Therapy and Therapeutic Hypothermia Despite 20 Minutes of Anoxia and 16 Hours of Hypoxia].

    Science.gov (United States)

    Stachon, Peter; Kalbhenn, Johannes; Walterspacher, Stephan; Bode, Christoph; Staudacher, Dawid

    2017-04-01

    Introduction  Drowning with submersion over 10 minutes is associated with a high mortality. Here, we present a case, in which a good neurological outcome was achieved after interdisciplinary, intensive care therapy despite submersion of 20 minutes followed by 16 hours of hypoxia. History  A 19 year old man drowned in fresh-water. After 20 minutes submersion he was localized and salvaged from 8 meters depth and primarily resuscitated successfully after 10 minutes. Within the next hour, there condition worsened by respiratory deterioration due to a massive capillary leak syndrome in addition to a disseminated intravascular coagulation. Treatment  This made implantation of a veno-venous ECMO (extracorporeal membrane oxygenation) therapy necessary. Despite intensive care medicine including extracorporeal therapy a sufficient oxygenation (arterial pO 2 > 60 mmHg) was reached only 16 hours after the drowning. Clinical Course  During this time the patient was treated with a mild therapeutic hypothermia for cerebral protection. Despite the prolonged hypoxia, ECMO could be removed five days after the drowning and the patient was extubated after another five days without significant neurological deficits. Conclusion  Despite submersion of 20 minutes followed by prolonged hypoxia, a good neurological outcome could be achieved in our patient. This case suggests, that tolerance of hypoxia is possibly underestimated after drowning. © Georg Thieme Verlag KG Stuttgart · New York.

  16. ECOLOGICAL CONTROL EQUIPMENT AND TECHNOLOGY OF UNDERWATER VEGETATION DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    V. TITINSCHNEIDER

    2008-10-01

    Full Text Available The excess of aquatic submerse vegetation development carries to the reduction of the real rearing area for the piscicultural material from the production farms and allow nestling of the ichthyophages bird species that decrease the fish production. Aquatic submerse vegetation stumble the utilization of aquatic zones for recreation and also wright function of basins utilized for the electric energy production, of micro electricity works through obstruction of the dams grid. The control of the aquatic submerse vegetation development, for Myriophyllum verticillatum, Ceratophyllum submersum, Urticularia vulgaris, Potamogeton natans, Nimphoides peltata species it is accomplish through the removing of some parts of these, preferably with all the stump system. Usually, these its accomplish with the floating equipments fit up with the thermic engines and the propulsion and governating elements who have harm over the fish and some others aquatic organisms through the noise, the displacing a large quality of water caused of propulsion systems and through the noxes elimination (flue, carburant trails, etc.. These technologies reside from the evacuation of the aquatic submerse vegetation and the stump systems of these with the help of an adjustable rake, hang up from the coast by a rope, wrapped to a drummer, who is trained by a motto-propeller group with a small installed power.

  17. Ocean Thermal Energy Conversion (OTEC) platform configuration and integration. Volume II. Conceptual design. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-06-01

    The purpose of this project is to evaluate six candidate hullforms as candidates for the OTEC commercial plant. This volume is a summary of the conceptual design including facility requirements, cost, schedule, and site sensitivity. Two OTEC commercial plant configurations are considered in this study: the ship and the semi-submersible. Engineering drawings are presented. (WHR)

  18. 75 FR 53301 - Notice of a Regional Project Waiver of Section 1605 (Buy American) of the American Recovery and...

    Science.gov (United States)

    2010-08-31

    ... purchase of a foreign manufactured submersible mixer to be installed in a new septage storage tank as part... proposed technical project specifications. The Regional Administrator is making this determination based on... Office of Administration and Resources Management has concurred on this decision to make an exception to...

  19. 75 FR 79374 - Notice of a Regional Project Waiver of Section 1605 (Buy American) of the American Recovery and...

    Science.gov (United States)

    2010-12-20

    ..., Connecticut for the purchase of a submersible well pump as part of the construction of a new bedrock well... specifications. The Regional Administrator is making this determination based on the review and recommendations... Resources Management has concurred on this decision to make an exception to Section 1605 of ARRA. This...

  20. 76 FR 17857 - Notice of a Project Waiver of Section 1605 (Buy American Requirement) of the American Recovery...

    Science.gov (United States)

    2011-03-31

    ... Amarillo, Texas (``City'') for the purchase of a 5 horsepower (HP) non-clog submersible pump, with NSF... circumstances. The Regional Administrator is making this determination based on the review and recommendations... Resources Management has concurred on this decision to make an exception to Section 1605 of ARRA. This...